WorldWideScience

Sample records for cancer molecular mechanisms

  1. Molecular Mechanisms Underlying Psychological Stress and Cancer.

    Science.gov (United States)

    Shin, Kyeong Jin; Lee, Yu Jin; Yang, Yong Ryoul; Park, Seorim; Suh, Pann-Ghill; Follo, Matilde Yung; Cocco, Lucio; Ryu, Sung Ho

    2016-01-01

    Psychological stress is an emotion experienced when people are under mental pressure or encounter unexpected problems. Extreme or repetitive stress increases the risk of developing human disease, including cardiovascular disease (CVD), immune diseases, mental disorders, and cancer. Several studies have shown an association between psychological stress and cancer growth and metastasis in animal models and case studies of cancer patients. Stress induces the secretion of stress-related mediators, such as catecholamine, cortisol, and oxytocin, via the activation of the hypothalamic-pituitary-adrenocortical (HPA) axis or the sympathetic nervous system (SNS). These stress-related hormones and neurotransmitters adversely affect stress-induced tumor progression and cancer therapy. Catecholamine is the primary factor that influences tumor progression. It can regulate diverse cellular signaling pathways through adrenergic receptors (ADRs), which are expressed by several types of cancer cells. Activated ADRs enhance the proliferation and invasion abilities of cancer cells, alter cell activity in the tumor microenvironment, and regulate the interaction between cancer and its microenvironment to promote tumor progression. Additionally, other stress mediators, such as glucocorticoids and oxytocin, and their cognate receptors are involved in stress-induced cancer growth and metastasis. Here, we will review how each receptor-mediated signal cascade contributes to tumor initiation and progression and discuss how we can use these molecular mechanisms for cancer therapy.

  2. Molecular mechanisms of metastasis in prostate cancer

    Institute of Scientific and Technical Information of China (English)

    Noel W.Clarke; Claire A.Hart; Mick D.Brown

    2009-01-01

    Prostate cancer (PCa) preferentially metastasizes to the bone marrow stroma of the axial skeleton.This activity is the principal cause of PCa morbidity and mortality.The exact mechanism of PCa metastasis is currently unknown,although considerable progress has been made in determining the key players in this process.In this review,we present the current understanding of the molecular processes driving PCa metastasis to the bone.

  3. Molecular mechanisms of tamoxifen-associated endometrial cancer (Review)

    OpenAIRE

    Hu, Rong; Hilakivi-Clarke, Leena; Clarke, Robert

    2015-01-01

    Tamoxifen has been prescribed to millions of females for breast cancer prevention or treatment. However, tamoxifen is known to significantly enhance the risk of developing endometrial lesions, including hyperplasia, polyps, carcinomas, and sarcoma. Notably, tamoxifen-associated endometrial cancer often has a poor clinical outcome. Understanding the molecular mechanism of tamoxifen-induced endometrial cancer is essential for developing strategies that minimize tamoxifen’s effects on the endome...

  4. Targeted therapies in epithelial ovarian cancer: Molecular mechanisms of action

    Institute of Scientific and Technical Information of China (English)

    Hiroaki; Itamochi

    2010-01-01

    Ovarian cancer is the leading cause of death in women with gynecological cancer. Most patients are diagnosed at an advanced stage and have a poor prognosis.Currently, surgical tumor debulking, followed by platinum- and taxane-based chemotherapy is the standard treatment for advanced ovarian cancer. However, these patients are at great risk of recurrence and emerging drug resistance. Therefore, novel treatment strategies are required to improve outcomes for women with advanced ovarian cancer. A variety of molecular targeted agents, the majority of which are monoclonal antibodies and small-molecule protein-kinase inhibitors, have been explored in the management of ovarian cancer. The targets of these agents include angiogenesis, the human epidermal growth factor receptor family, ubiquitinproteasome pathway, epigenetic modulators, poly(ADPribose) polymerase (PARP), and mammalian target of rapamycin (mTOR) signaling pathway, which are aberrant in tumor tissue. The antiangiogenic agent, bevacizumab, has been reported as the most effective targeted agent and should be included in the standard chemotherapeutic regimen for advanced ovarian cancer. PARP inhibitors, which are mainly used in breast and ovarian cancer susceptibility gene-mutated patients, and mTOR inhibitors are also attractive treatment strategies, either alone or combination with chemotherapy, for ovarian cancer. Understanding the tumor molecular biology and identification of predictive biomarkers are essential steps for selection of the best treatment strategies. This article reviews the molecular mechanisms of the most promising targeted agents that are under early phase clinical evaluation for ovarian cancer.

  5. Molecular mechanisms of TRAIL-induced apoptosis of cancer cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Tumor Necrosis Factor-related Apoptosis-inducing Ligand (TRAIL) is a recently identified member of the tumor necrosis factor (TNF) family[1]. Numerous studies indicate that TRAIL can induce apoptosis of cancer cells but not of normal cells, pointing to the possibility of de-veloping TRAIL into a cancer drug[2-4]. This review will summary the molecular mechanisms of TRAIL-induced apoptosis and discuss the questions to be resolved in this field.

  6. Molecular Mechanism Underlying Lymphatic Metastasis in Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Zhiwen Xiao

    2014-01-01

    Full Text Available As the most challenging human malignancies, pancreatic cancer is characterized by its insidious symptoms, low rate of surgical resection, high risk of local invasion, metastasis and recurrence, and overall dismal prognosis. Lymphatic metastasis, above all, is recognized as an early adverse event in progression of pancreatic cancer and has been described to be an independent poor prognostic factor. It should be noted that the occurrence of lymphatic metastasis is not a casual or stochastic but an ineluctable and designed event. Increasing evidences suggest that metastasis-initiating cells (MICs and the microenvironments may act as a double-reed style in this crime. However, the exact mechanisms on how they function synergistically for this dismal clinical course remain largely elusive. Therefore, a better understanding of its molecular and cellular mechanisms involved in pancreatic lymphatic metastasis is urgently required. In this review, we will summarize the latest advances on lymphatic metastasis in pancreatic cancer.

  7. Retinoic acid receptors: from molecular mechanisms to cancer therapy.

    Science.gov (United States)

    di Masi, Alessandra; Leboffe, Loris; De Marinis, Elisabetta; Pagano, Francesca; Cicconi, Laura; Rochette-Egly, Cécile; Lo-Coco, Francesco; Ascenzi, Paolo; Nervi, Clara

    2015-02-01

    Retinoic acid (RA), the major bioactive metabolite of retinol or vitamin A, induces a spectrum of pleiotropic effects in cell growth and differentiation that are relevant for embryonic development and adult physiology. The RA activity is mediated primarily by members of the retinoic acid receptor (RAR) subfamily, namely RARα, RARβ and RARγ, which belong to the nuclear receptor (NR) superfamily of transcription factors. RARs form heterodimers with members of the retinoid X receptor (RXR) subfamily and act as ligand-regulated transcription factors through binding specific RA response elements (RAREs) located in target genes promoters. RARs also have non-genomic effects and activate kinase signaling pathways, which fine-tune the transcription of the RA target genes. The disruption of RA signaling pathways is thought to underlie the etiology of a number of hematological and non-hematological malignancies, including leukemias, skin cancer, head/neck cancer, lung cancer, breast cancer, ovarian cancer, prostate cancer, renal cell carcinoma, pancreatic cancer, liver cancer, glioblastoma and neuroblastoma. Of note, RA and its derivatives (retinoids) are employed as potential chemotherapeutic or chemopreventive agents because of their differentiation, anti-proliferative, pro-apoptotic, and anti-oxidant effects. In humans, retinoids reverse premalignant epithelial lesions, induce the differentiation of myeloid normal and leukemic cells, and prevent lung, liver, and breast cancer. Here, we provide an overview of the biochemical and molecular mechanisms that regulate the RA and retinoid signaling pathways. Moreover, mechanisms through which deregulation of RA signaling pathways ultimately impact on cancer are examined. Finally, the therapeutic effects of retinoids are reported. PMID:25543955

  8. Molecular mechanisms underlying progesterone-enhanced breast cancer cell migration.

    Science.gov (United States)

    Wang, Hui-Chen; Lee, Wen-Sen

    2016-01-01

    Progesterone (P4) was demonstrated to inhibit migration in vascular smooth muscle cells (VSMCs), but to enhance migration in T47D breast cancer cells. To investigate the mechanism responsible for this switch in P4 action, we examined the signaling pathway responsible for the P4-induced migration enhancement in breast cancer cell lines, T47D and MCF-7. Here, we demonstrated that P4 activated the cSrc/AKT signaling pathway, subsequently inducing RSK1 activation, which in turn increased phosphorylation of p27 at T198 and formation of the p27pT198-RhoA complex in the cytosol, thereby preventing RhoA degradation, and eventually enhanced migration in T47D cells. These findings were confirmed in the P4-treated MCF-7. Comparing the P4-induced molecular events in between breast cancer cells and VSMCs, we found that P4 increased p27 phosphorylation at T198 in breast cancer cells through RSK1 activation, while P4 increased p27 phosphorlation at Ser10 in VSMCs through KIS activation. P27pT198 formed the complex with RhoA and prevented RhoA degradation in T47D cells, whereas p-p27Ser10 formed the complex with RhoA and caused RhoA degradation in VSMCs. The results of this study highlight the molecular mechanism underlying P4-enhanced breast cancer cell migration, and suggest that RSK1 activation is responsible for the P4-induced migration enhancement in breast cancer cells. PMID:27510838

  9. Molecular mechanisms of pharmacological doses of ascorbate on cancer cells.

    Science.gov (United States)

    Venturelli, Sascha; Sinnberg, Tobias W; Niessner, Heike; Busch, Christian

    2015-06-01

    Intravenous application of high-dose ascorbate (vitamin C) has been used in complementary medicine since the 1970s to treat cancer patients. In recent years it became evident that high-dose ascorbate in the millimolar range bears selective cytotoxic effects on cancer cells in vitro and in vivo. This anticancer effect is dose dependent, catalyzed by serum components and mediated by reactive oxygen species and ascorbyl radicals, making ascorbate a pro-oxidative pro-drug that catalyzes hydrogen peroxide production in tissues instead of acting as a radical scavenger. It further depends on HIF-1 signaling and oxygen pressure, and shows a strong epigenetic signature (alteration of DNA-methylation and induction of tumor-suppressing microRNAs in cancer cells). The detailed understanding of ascorbate-induced antiproliferative molecular mechanisms warrants in-depth preclinical evaluation in cancer-bearing animal models for the optimization of an efficacious therapy regimen (e.g., combination with hyperbaric oxygen or O2-sensitizers) that subsequently need to be evaluated in clinical trials. PMID:26065536

  10. The epidemiology and molecular mechanisms linking obesity, diabetes, and cancer.

    Science.gov (United States)

    Ferguson, Rosalyn D; Gallagher, Emily J; Scheinman, Eyal J; Damouni, Rawan; LeRoith, Derek

    2013-01-01

    The worldwide epidemic of obesity is associated with increasing rates of the metabolic syndrome and type 2 diabetes. Epidemiological studies have reported that these conditions are linked to increased rates of cancer incidence and mortality. Obesity, particularly abdominal obesity, is associated with insulin resistance and the development of dyslipidemia, hyperglycemia, and ultimately type 2 diabetes. Although many metabolic abnormalities occur with obesity and type 2 diabetes, insulin resistance and hyperinsulinemia appear to be central to these conditions and may contribute to dyslipidemia and altered levels of circulating estrogens and androgens. In this review, we will discuss the epidemiological and molecular links between obesity, type 2 diabetes, and cancer, and how hyperinsulinemia and dyslipidemia may contribute to cancer development. We will discuss how these metabolic abnormalities may interact with estrogen signaling in breast cancer growth. Finally, we will discuss the effects of type 2 diabetes medications on cancer risk. PMID:23810003

  11. Quantum Interactomics and Cancer Molecular Mechanisms: I. Report Outline

    CERN Document Server

    Baianu, I C

    2004-01-01

    Single cell interactomics in simpler organisms, as well as somatic cell interactomics in multicellular organisms, involve biomolecular interactions in complex signalling pathways that were recently represented in modular terms by quantum automata with ‘reversible behavior’ representing normal cell cycling and division. Other implications of such quantum automata, modular modeling of signaling pathways and cell differentiation during development are in the fields of neural plasticity and brain development leading to quantum-weave dynamic patterns and specific molecular processes underlying extensive memory, learning, anticipation mechanisms and the emergence of human consciousness during the early brain development in children. Cell interactomics is here represented for the first time as a mixture of ‘classical’ states that determine molecular dynamics subject to Boltzmann statistics and ‘steady-state’, metabolic (multi-stable) manifolds, together with ‘configuration’ spaces of metastable quant...

  12. Molecular mechanisms of long noncoding RNAs on gastric cancer.

    Science.gov (United States)

    Li, Tianwen; Mo, Xiaoyan; Fu, Liyun; Xiao, Bingxiu; Guo, Junming

    2016-02-23

    Long noncoding RNAs (lncRNAs) are non-protein coding transcripts longer than 200 nucleotides. Aberrant expression of lncRNAs has been found associated with gastric cancer, one of the most malignant tumors. By complementary base pairing with mRNAs or forming complexes with RNA binding proteins (RBPs), some lncRNAs including GHET1, MALAT1, and TINCR may mediate mRNA stability and splicing. Other lncRNAs, such as BC032469, GAPLINC, and HOTAIR, participate in the competing endogenous RNA (ceRNA) network. Under certain circumstances, ANRIL, GACAT3, H19, MEG3, and TUSC7 exhibit their biological roles by associating with microRNAs (miRNAs). By recruiting histone-modifying complexes, ANRIL, FENDRR, H19, HOTAIR, MALAT1, and PVT1 may inhibit the transcription of target genes in cis or trans. Through these mechanisms, lncRNAs form RNA-dsDNA triplex. CCAT1, GAPLINC, GAS5, H19, MEG3, and TUSC7 play oncogenic or tumor suppressor roles by correlated with tumor suppressor P53 or onco-protein c-Myc, respectively. In conclusion, interaction with DNA, RNA and proteins is involved in lncRNAs' participation in gastric tumorigenesis and development. PMID:26788991

  13. Molecular mechanisms of cisplatin resistance in cervical cancer

    OpenAIRE

    Zhu, Xueqiong

    2016-01-01

    Haiyan Zhu, Hui Luo, Wenwen Zhang, Zhaojun Shen, Xiaoli Hu, Xueqiong Zhu Department of Obstetrics and Gynecology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, People’s Republic of China Abstract: Patients with advanced or recurrent cervical cancer have poor prognosis, and their 1-year survival is only 10%–20%. Chemotherapy is considered as the standard treatment for patients with advanced or recurrent cervical cancer, and cisplatin appears to tr...

  14. Molecular mechanisms of cisplatin resistance in cervical cancer

    OpenAIRE

    Zhu H; Luo H; Zhang W; Shen Z; Hu X; Zhu X

    2016-01-01

    Haiyan Zhu, Hui Luo, Wenwen Zhang, Zhaojun Shen, Xiaoli Hu, Xueqiong Zhu Department of Obstetrics and Gynecology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, People’s Republic of China Abstract: Patients with advanced or recurrent cervical cancer have poor prognosis, and their 1-year survival is only 10%–20%. Chemotherapy is considered as the standard treatment for patients with advanced or recurrent cervical cancer, and cisplatin appears to treat the ...

  15. Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines: less involvement of metallothionein

    Directory of Open Access Journals (Sweden)

    Moon Sung-Pyo

    2004-10-01

    Full Text Available Abstract Background Heptaplatin is a new platinum derivative with anticancer activity against various cancer cell lines, including cisplatin-resistant cancer cell lines (Cancer Chemother Pharmacol 1995; 35: 441. Methods Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines has been investigated in connection with metallothionein (MT. Cytotoxicity was determined by an MTT assay. MT mRNA, was determined by RT-PCR assay. Transfection study was carried out to examine the function of MT. Results Of various gastric cancer cell lines, SNU-638 and SNU-601 showed the highest and lowest levels of MT mRNA, respectively, showing 80-fold difference. The IC50 values of SNU-638 to cisplatin, carboplatin and heptaplatin were 11.2-fold, 5.1-fold and 2.0-fold greater than those of SNU-601, respectively. Heptaplatin was more effective against cisplatin-resistant and MT-transfected gastric cancer sublines than cisplatin or carboplatin was. In addition, heptaplatin attenuated cadmium, but not zinc, induction of MT. Conclusion These results indicate that molecular mechanisms of heptaplatin effective against cisplatin-resistant gastric cancer sublines is at least in part due to the less involvement of MT in heptaplatin resistance as well as its attenuation of MT induction.

  16. Molecular mechanisms linking adipokines to obesity-related colon cancer: focus on leptin.

    Science.gov (United States)

    Drew, Janice E

    2012-02-01

    Obesity is linked to increased risk of colon cancer, currently the third most common cancer. Consequently rising levels of obesity worldwide are likely to significantly impact on obesity-related colon cancers in the decades to come. Understanding the molecular mechanisms whereby obesity increases colon cancer risk is thus a focus for research to inform strategies to prevent the increasing trend in obesity-related cancers. This review will consider research on deregulation of adipokine signalling, a consequence of altered adipokine hormone secretion from excess adipose tissue, with a focus on leptin, which has been studied extensively as a potential mediator of obesity-related colon cancer. Numerous investigations using colon cell lines in vitro, in vivo studies in rodents and investigations of colon cancer patients illuminate the complexity of the interactions of leptin with colon tissues via leptin receptors expressed by the colon epithelium. Although evidence indicates a role for leptin in proliferation of colon epithelial cells in vitro, this has been contradicted by studies in rodent models. However, recent studies have indicated that leptin may influence inflammatory mediators linked with colon cancer and also promote cell growth dependent on genotype and is implicated in growth promotion of colon cancer cells. Studies in human cancer patients indicate that there may be different tumour sub-types with varying levels of leptin receptor expression, indicating the potential for leptin to induce variable responses in the different tumour types. These studies have provided insights into the complex interplay of adipokines with responsive tissues prone to obesity-related colon cancer. Deregulation of adipokine signalling via adipokine receptors located in the colon appears to be a significant factor in obesity-related colon cancer. Molecular profiling of colon tumours will be a useful tool in future strategies to characterise the influence that adipokines may have

  17. Multiple Molecular and Cellular Mechanisms of Action of Lycopene in Cancer Inhibition

    Directory of Open Access Journals (Sweden)

    Cristina Trejo-Solís

    2013-01-01

    Full Text Available Epidemiological studies suggest that including fruits, vegetables, and whole grains in regular dietary intake might prevent and reverse cellular carcinogenesis, reducing the incidence of primary tumours. Bioactive components present in food can simultaneously modulate more than one carcinogenic process, including cancer metabolism, hormonal balance, transcriptional activity, cell-cycle control, apoptosis, inflammation, angiogenesis and metastasis. Some studies have shown an inverse correlation between a diet rich in fruits, vegetables, and carotenoids and a low incidence of different types of cancer. Lycopene, the predominant carotenoid found in tomatoes, exhibits a high antioxidant capacity and has been shown to prevent cancer, as evidenced by clinical trials and studies in cell culture and animal models. In vitro studies have shown that lycopene treatment can selectively arrest cell growth and induce apoptosis in cancer cells without affecting normal cells. In vivo studies have revealed that lycopene treatment inhibits tumour growth in the liver, lung, prostate, breast, and colon. Clinical studies have shown that lycopene protects against prostate cancer. One of the main challenges in cancer prevention is the integration of new molecular findings into clinical practice. Thus, the identification of molecular biomarkers associated with lycopene levels is essential for improving our understanding of the mechanisms underlying its antineoplastic activity.

  18. Natural Products as Promising Antitumoral Agents in Breast Cancer: Mechanisms of Action and Molecular Targets.

    Science.gov (United States)

    Bonofiglio, Daniela; Giordano, Cinzia; De Amicis, Francesca; Lanzino, Marilena; Andò, Sebastiano

    2016-01-01

    Extensive research over the past several decades has identified numerous dietary and phytochemical compounds that have chemopreventive potential and could represent an important source of anti-cancer lead molecules. In this scenario several nutritional factors have attracted considerable attention as modifiable risk factor in the prevention of breast cancer, the most frequently diagnosed cancer and a major cause of death among women worldwide. There is an immediate need for more effective and less toxic therapeutic and preventive strategies for breast cancers able also to counteract the recurrent phenomenon of resistance to hormonal and targeted therapy that represent the first-line treatment in the management of breast cancer patients. The present review focuses on chemopreventive and anti-cancer activities of different bioactive compounds obtained from dietary sources such as Omega-3 fatty acids, naturally present in fish, Resveratrol (3,5,40-trihydroxy-transstilbene), a phytoalexin found in grapes and Epigallocatechin Gallate, a polyphenolic compound found in green tea, or purified from medicinal plant (Oldenlandia Diffusa) and fruits (Ziziphus Jujube) highlighting their potential use in breast cancer treatment. Herein, we discuss the molecular mechanisms by which the bioactive compounds can inhibit carcinogenesis by regulating antioxidant enzyme activities, and inducing antiproliferative and apoptotic effects in different breast cancer cell lines. Understanding the mechanism of action of dietary compounds or traditionally used herbs having potential preventive and therapeutic effects on cancer may provide a rationale for further translational studies. This review emphasizes the importance, in the next future, of a proper scientific validation of these natural bioactive compounds for clinical use in the therapeutic portfolio for breast cancer. PMID:26156544

  19. Molecular Mechanics

    OpenAIRE

    Vanommeslaeghe, Kenno; Guvench, Olgun; Alexander D MacKerell

    2014-01-01

    Molecular Mechanics (MM) force fields are the methods of choice for protein simulations, which are essential in the study of conformational flexibility. Given the importance of protein flexibility in drug binding, MM is involved in most if not all Computational Structure-Based Drug Discovery (CSBDD) projects. This section introduces the reader to the fundamentals of MM, with a special emphasis on how the target data used in the parametrization of force fields determine their strengths and wea...

  20. Antiproliferative and Molecular Mechanism of Eugenol-Induced Apoptosis in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Eko Supriyanto

    2012-05-01

    Full Text Available Phenolic phytochemicals are a broad class of nutraceuticals found in plants which have been extensively researched by scientists for their health-promoting potential. One such a compound which has been comprehensively used is eugenol (4-allyl-2-methoxyphenol, which is the active component of Syzigium aromaticum (cloves. Aromatic plants like nutmeg, basil, cinnamon and bay leaves also contain eugenol. Eugenol has a wide range of applications like perfumeries, flavorings, essential oils and in medicine as a local antiseptic and anesthetic. Increasing volumes of literature showed eugenol possesses antioxidant, antimutagenic, antigenotoxic, anti-inflammatory and anticancer properties. Molecular mechanism of eugenol-induced apoptosis in melanoma, skin tumors, osteosarcoma, leukemia, gastric and mast cells has been well documented. This review article will highlight the antiproliferative activity and molecular mechanism of the eugenol induced apoptosis against the cancer cells and animal models.

  1. Antiproliferative and molecular mechanism of eugenol-induced apoptosis in cancer cells.

    Science.gov (United States)

    Jaganathan, Saravana Kumar; Supriyanto, Eko

    2012-01-01

    Phenolic phytochemicals are a broad class of nutraceuticals found in plants which have been extensively researched by scientists for their health-promoting potential. One such a compound which has been comprehensively used is eugenol (4-allyl-2-methoxyphenol), which is the active component of Syzigium aromaticum (cloves). Aromatic plants like nutmeg, basil, cinnamon and bay leaves also contain eugenol. Eugenol has a wide range of applications like perfumeries, flavorings, essential oils and in medicine as a local antiseptic and anesthetic. Increasing volumes of literature showed eugenol possesses antioxidant, antimutagenic, antigenotoxic, anti-inflammatory and anticancer properties. Molecular mechanism of eugenol-induced apoptosis in melanoma, skin tumors, osteosarcoma, leukemia, gastric and mast cells has been well documented. This review article will highlight the antiproliferative activity and molecular mechanism of the eugenol induced apoptosis against the cancer cells and animal models. PMID:22634840

  2. Antitumor effects and molecular mechanisms of ponatinib on endometrial cancer cells harboring activating FGFR2 mutations.

    Science.gov (United States)

    Kim, Do-Hee; Kwak, Yeonui; Kim, Nam Doo; Sim, Taebo

    2016-01-01

    Aberrant mutational activation of FGFR2 is associated with endometrial cancers (ECs). AP24534 (ponatinib) currently undergoing clinical trials has been known to be an orally available multi-targeted tyrosine kinase inhibitor. Our biochemical kinase assay showed that AP24534 is potent against wild-type FGFR1-4 and 5 mutant FGFRs (V561M-FGFR1, N549H-FGFR2, K650E-FGFR3, G697C-FGFR3, N535K-FGFR4) and possesses the strongest kinase-inhibitory activity on N549H-FGFR2 (IC50 of 0.5 nM) among all FGFRs tested. We therefore investigated the effects of AP24534 on endometrial cancer cells harboring activating FGFR2 mutations and explored the underlying molecular mechanisms. AP24534 significantly inhibited the proliferation of endometrial cancer cells bearing activating FGFR2 mutations (N549K, K310R/N549K, S252W) and mainly induced G1/S cell cycle arrest leading to apoptosis. AP24534 also diminished the kinase activity of immunoprecipitated FGFR2 derived from MFE-296 and MFE-280 cells and reduced the phosphorylation of FGFR2 and FRS2 on MFE-296 and AN3CA cells. AP24534 caused substantial reductions in ERK phosphorylation, PLCγ signaling and STAT5 signal transduction on ECs bearing FGFR2 activating mutations. Akt signaling pathway was also deactivated by AP24534. AP24534 causes the chemotherapeutic effect through mainly the blockade of ERK, PLCγ and STAT5 signal transduction on ECs. Moreover, AP24534 inhibited migration and invasion of endometrial cancer cells with FGFR2 mutations. In addition, AP24534 significantly blocked anchorage-independent growth of endometrial cancer cells. We, for the first time, report the molecular mechanisms by which AP24534 exerts antitumor effects on ECs with FGFR2 activating mutations, which would provide mechanistic insight into ongoing clinical investigations of AP24534 for ECs.

  3. The molecular mechanism of different sensitivity of breast cancer cell lines to TRAIL

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jindan; LIU Yanxin; LIU Shilian; ZHENG Dexian

    2004-01-01

    Although Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis of various cancer cells, some caner cell lines are resistant to TRAIL-induced cell death. To investigate the molecular mechanisms underlying TRAIL-resistance, two human breast cancer cell lines, MCF-7 (resistant to TRAIL) and MDA-MB-231 (sensitive to TRAIL), were used as a model system to analyze the different sensitivities to TRAIL cytotoxicity. PKCδ inhibitor rottlerin, but not MEK and ERK1/2 inhibitor U0126 nor PI3K inhibitor LY294002, was shown to enhance TRAIL-induced apoptosis in MCF-7 cells significantly, suggesting that PKCδ might play an important role in the resistance of MCF-7 cells to TRAIL. In contrast, rottlerin, U0126, and Ly294002 had no effect on MDA-MB-231 apoptosis induced by TRAIL under the same conditions. Further experiment showed that the combination of rottlerin and TRAIL cleaved PARP in the MCF-7 cells synergistically, but not in the MDA-MB-231 cells. The role of PKCδ in TRAIL-resistant MCF-7 cells was confirmed by knocking down the endogenous PKCδ expression using RNAi technology. Furthermore, caspase-3 reconstitution in MCF-7 cells was unable to alter PKCδ expression, suggesting that innate caspase-3 deficient in the cells does not cause PKCδ high expression. These data provide evidence for the first time that PKCδ plays a critical role in breast cancer cell lines to TRAIL cytotoxicity.

  4. Is diabetes a causal agent for colorectal cancer? Pathophysiological and molecular mechanisms

    Institute of Scientific and Technical Information of China (English)

    Olga Giouleme; Michael D Diamantidis; Marios G Katsaros

    2011-01-01

    The possible relationship between diabetes mellitus (DM) and colorectal cancer (CRC), concerning pathophysiological and molecular mechanisms is highlighted in this review. The most recent and complete articles and developments in this particular field were thoroughly reviewed. Common risk factors, such as obesity, sedentary lifestyle, and Western diet between DM and CRC, led to the theory that DM might be a causal agent for CRC development. Various studies have connected type 2 DM and CRC, either proximal or distal, in both sexes. Additionally, chronic insulin treatment has been linked with increased colorectal tumor risk among type 2 diabetic patients. Interestingly, elevated hemoglobin A1c has been proven to be an independent predictor of aggressive clinical behavior in CRC patients. These mechanisms include the insulin-like growth factor-hyperinsulinemia theory and the participation of oncogenic intracellular signaling pathways. Furthermore, it has been proposed that Cox-2 inhibitors might have a role in decreasing the incidence of CRC. Finally, the use of statins to reduce the risk for colon cancer in patients with diabetes has remained controversial. Diabetic patients over 50 should receive counseling regarding their elevated risk for CRC, and screening colonoscopy should be recommended before initiating insulin therapy. However, there are no current guidelines, and this strategy is not yet applicable to some countries, as the corresponding risk would not allow screening colonoscopy to be adopted. There is strong evidence to indicate that DM is a causal agent for CRC development. This conclusion provides new impetus for re-evaluating CRC screening worldwide.

  5. Bitter melon juice targets molecular mechanisms underlying gemcitabine resistance in pancreatic cancer cells.

    Science.gov (United States)

    Somasagara, Ranganatha R; Deep, Gagan; Shrotriya, Sangeeta; Patel, Manisha; Agarwal, Chapla; Agarwal, Rajesh

    2015-04-01

    Pancreatic cancer (PanC) is one of the most lethal malignancies, and resistance towards gemcitabine, the front-line chemotherapy, is the main cause for dismal rate of survival in PanC patients; overcoming this resistance remains a major challenge to treat this deadly malignancy. Whereas several molecular mechanisms are known for gemcitabine resistance in PanC cells, altered metabolism and bioenergetics are not yet studied. Here, we compared metabolic and bioenergetic functions between gemcitabine-resistant (GR) and gemcitabine-sensitive (GS) PanC cells and underlying molecular mechanisms, together with efficacy of a natural agent bitter melon juice (BMJ). GR PanC cells showed distinct morphological features including spindle-shaped morphology and a decrease in E-cadherin expression. GR cells also showed higher ATP production with an increase in oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). Molecular studies showed higher expression of glucose transporters (GLUT1 and 4) suggesting an increase in glucose uptake by GR cells. Importantly, GR cells showed a significant increase in Akt and ERK1/2 phosphorylation and their inhibition decreased cell viability, suggesting their role in survival and drug resistance of these cells. Recently, we reported strong efficacy of BMJ against a panel of GS cells in culture and nude mice, which we expanded here and found that BMJ was also effective in decreasing both Akt and ERK1/2 phosphorylation and viability of GR PanC cells. Overall, we have identified novel mechanisms of gemcitabine resistance in PanC cells which are targeted by BMJ. Considering the short survival in PanC patients, our findings could have high translational potential in controlling this deadly malignancy. PMID:25672620

  6. Molecular mechanism of bitter melon juice efficacy against pancreatic cancer. | Division of Cancer Prevention

    Science.gov (United States)

    DESCRIPTION (provided by applicant): Pancreatic cancer (PanC) is an aggressive disease;median life of PanC patients post-diagnosis is been tested in several clinical trials for its anti-diabetic effects and has plenty of human safety data. We, therefore, anticipate that the positive outcomes from the proposed studies will provide compelling rationale for initiating clinical trials to establish BMJ activity against human pancreatic cancer. |

  7. Hedgehog signaling antagonist GDC-0449 (Vismodegib inhibits pancreatic cancer stem cell characteristics: molecular mechanisms.

    Directory of Open Access Journals (Sweden)

    Brahma N Singh

    Full Text Available BACKGROUND: Recent evidence from in vitro and in vivo studies has demonstrated that aberrant reactivation of the Sonic Hedgehog (SHH signaling pathway regulates genes that promote cellular proliferation in various human cancer stem cells (CSCs. Therefore, the chemotherapeutic agents that inhibit activation of Gli transcription factors have emerged as promising novel therapeutic drugs for pancreatic cancer. GDC-0449 (Vismodegib, orally administrable molecule belonging to the 2-arylpyridine class, inhibits SHH signaling pathway by blocking the activities of Smoothened. The objectives of this study were to examine the molecular mechanisms by which GDC-0449 regulates human pancreatic CSC characteristics in vitro. METHODOLOGY/PRINCIPAL FINDINGS: GDC-0499 inhibited cell viability and induced apoptosis in three pancreatic cancer cell lines and pancreatic CSCs. This inhibitor also suppressed cell viability, Gli-DNA binding and transcriptional activities, and induced apoptosis through caspase-3 activation and PARP cleavage in pancreatic CSCs. GDC-0449-induced apoptosis in CSCs showed increased Fas expression and decreased expression of PDGFRα. Furthermore, Bcl-2 was down-regulated whereas TRAIL-R1/DR4 and TRAIL-R2/DR5 expression was increased following the treatment of CSCs with GDC-0449. Suppression of both Gli1 plus Gli2 by shRNA mimicked the changes in cell viability, spheroid formation, apoptosis and gene expression observed in GDC-0449-treated pancreatic CSCs. Thus, activated Gli genes repress DRs and Fas expressions, up-regulate the expressions of Bcl-2 and PDGFRα and facilitate cell survival. CONCLUSIONS/SIGNIFICANCE: These data suggest that GDC-0499 can be used for the management of pancreatic cancer by targeting pancreatic CSCs.

  8. Molecular mechanism and clinical impact of APOBEC3B-catalyzed mutagenesis in breast cancer.

    Science.gov (United States)

    Harris, Reuben S

    2015-01-01

    Cancer genomic DNA sequences enable identification of all mutations and suggest targets for precision medicine. The identities and patterns of the mutations themselves also provide critical information for deducing the originating DNA damaging agents, causal molecular mechanisms, and thus additional therapeutic targets. A classic example is ultraviolet light, which crosslinks adjacent pyrimidines and leads to C-to-T transitions. A new example is the DNA cytosine deaminase APOBEC3B, which was identified recently as a source of DNA damage and mutagenesis in breast, head/neck, cervix, bladder, lung, ovary, and to lesser extents additional cancer types. This enzyme is normally an effector protein in the innate immune response to virus infection but upregulation in these cancer types causes elevated levels of genomic C-to-U deamination events, which manifest as C-to-T transitions and C-to-G transversions within distinct DNA trinucleotide contexts (preferentially 5'-TCA and 5'-TCG). Genomic C-to-U deamination events within the same trinucleotide contexts also lead to cytosine mutation clusters (kataegis), and may precipitate visible chromosomal aberrations such as translocations. Clinical studies indicate that APOBEC3B upregulation correlates with poorer outcomes for estrogen receptor-positive breast cancer patients, including shorter durations of disease-free survival and overall survival after surgery. APOBEC3B may therefore have both diagnostic and prognostic potential. APOBEC3B may also be a candidate for therapeutic targeting because inhibition of this non-essential enzyme is predicted to decrease tumor mutation rates and diminish the likelihood of undesirable mutation-dependent outcomes such as recurrence, metastasis, and the development of therapy resistant tumors. PMID:25848704

  9. Chinese Medicines Induce Cell Death: The Molecular and Cellular Mechanisms for Cancer Therapy

    OpenAIRE

    Xuanbin Wang; Yibin Feng; Ning Wang; Fan Cheung; Hor Yue Tan; Sen Zhong; Charlie Li; Seiichi Kobayashi

    2014-01-01

    Chinese medicines have long history in treating cancer. With the growing scientific evidence of biomedical researches and clinical trials in cancer therapy, they are increasingly accepted as a complementary and alternative treatment. One of the mechanisms is to induce cancer cell death. Aim. To comprehensively review the publications concerning cancer cell death induced by Chinese medicines in recent years and provide insights on anticancer drug discovery from Chinese medicines. Materials and...

  10. Cellular and Molecular Mechanisms of 3,3′-Diindolylmethane in Gastrointestinal Cancer

    Directory of Open Access Journals (Sweden)

    Soo Mi Kim

    2016-07-01

    Full Text Available Studies in humans have shown that 3,3′-diindolylmethane (DIM, which is found in cruciferous vegetables, such as cabbage and broccoli, is effective in the attenuation of gastrointestinal cancers. This review presents the latest findings on the use, targets, and modes of action of DIM for the treatment of human gastrointestinal cancers. DIM acts upon several cellular and molecular processes in gastrointestinal cancer cells, including apoptosis, autophagy, invasion, cell cycle regulation, metastasis, angiogenesis, and endoplasmic reticulum (ER stress. In addition, DIM increases the efficacy of other drugs or therapeutic chemicals when used in combinatorial treatment for gastrointestinal cancer. The studies to date offer strong evidence to support the use of DIM as an anticancer and therapeutic agent for gastrointestinal cancer. Therefore, this review provides a comprehensive understanding of the preventive and therapeutic properties of DIM in addition to its different perspective on the safety of DIM in clinical applications for the treatment of gastrointestinal cancers.

  11. Cellular and Molecular Mechanisms of 3,3'-Diindolylmethane in Gastrointestinal Cancer.

    Science.gov (United States)

    Kim, Soo Mi

    2016-01-01

    Studies in humans have shown that 3,3'-diindolylmethane (DIM), which is found in cruciferous vegetables, such as cabbage and broccoli, is effective in the attenuation of gastrointestinal cancers. This review presents the latest findings on the use, targets, and modes of action of DIM for the treatment of human gastrointestinal cancers. DIM acts upon several cellular and molecular processes in gastrointestinal cancer cells, including apoptosis, autophagy, invasion, cell cycle regulation, metastasis, angiogenesis, and endoplasmic reticulum (ER) stress. In addition, DIM increases the efficacy of other drugs or therapeutic chemicals when used in combinatorial treatment for gastrointestinal cancer. The studies to date offer strong evidence to support the use of DIM as an anticancer and therapeutic agent for gastrointestinal cancer. Therefore, this review provides a comprehensive understanding of the preventive and therapeutic properties of DIM in addition to its different perspective on the safety of DIM in clinical applications for the treatment of gastrointestinal cancers. PMID:27447608

  12. Synergistic Effect and Molecular Mechanisms of Traditional Chinese Medicine on Regulating Tumor Microenvironment and Cancer Cells

    OpenAIRE

    Jingnan Xu; Zhuo Song; Qiujun Guo; Jie Li

    2016-01-01

    The interaction of tumor cells with the microenvironment is like a relationship between the “seeds” and “soil,” which is a hotspot in recent cancer research. Targeting at tumor microenvironment as well as tumor cells has become a new strategy for cancer treatment. Conventional cancer treatments mostly focused on single targets or single mechanism (the seeds or part of the soil); few researches intervened in the whole tumor microenvironment and achieved ideal therapeutic effect as expected. Tr...

  13. Curcumin: Updated Molecular Mechanisms and Intervention Targets in Human Lung Cancer

    Directory of Open Access Journals (Sweden)

    Hong Yin

    2012-03-01

    Full Text Available Curcumin, a yellow pigment derived from Curcuma longa Linn, has attracted great interest in the research of cancer during the past decades. Extensive studies documented that curcumin attenuates cancer cell proliferation and promotes apoptosis in vivo and in vitro. Curcumin has been demonstrated to interact with multiple molecules and signal pathways, which makes it a potential adjuvant anti-cancer agent to chemotherapy. Previous investigations focus on the mechanisms of action for curcumin, which is shown to manipulate transcription factors and induce apoptosis in various kinds of human cancer. Apart from transcription factors and apoptosis, emerging studies shed light on latent targets of curcumin against epidermal growth factor receptor (EGFR, microRNAs (miRNA, autophagy and cancer stem cell. The present review predominantly discusses significance of EGFR, miRNA, autophagy and cancer stem cell in lung cancer therapy. Curcumin as a natural phytochemicals could communicate with these novel targets and show synergism to chemotherapy. Additionally, curcumin is well tolerated in humans. Therefore, EGFR-, miRNA-, autophagy- and cancer stem cell-based therapy in the presence of curcumin might be promising mechanisms and targets in the therapeutic strategy of lung cancer.

  14. Using large-scale genome variation cohorts to decipher the molecular mechanism of cancer.

    Science.gov (United States)

    Habermann, Nina; Mardin, Balca R; Yakneen, Sergei; Korbel, Jan O

    2016-01-01

    Characterizing genomic structural variations (SVs) in the human genome remains challenging, and there is a growing interest to understand somatic SVs occurring in cancer, a disease of the genome. A havoc-causing SV process known as chromothripsis scars the genome when localized chromosome shattering and repair occur in a one-off catastrophe. Recent efforts led to the development of a set of conceptual criteria for the inference of chromothripsis events in cancer genomes and to the development of experimental model systems for studying this striking DNA alteration process in vitro. We discuss these approaches, and additionally touch upon current "Big Data" efforts that employ hybrid cloud computing to enable studies of numerous cancer genomes in an effort to search for commonalities and differences in molecular DNA alteration processes in cancer. PMID:27342254

  15. Using large-scale genome variation cohorts to decipher the molecular mechanism of cancer.

    Science.gov (United States)

    Habermann, Nina; Mardin, Balca R; Yakneen, Sergei; Korbel, Jan O

    2016-01-01

    Characterizing genomic structural variations (SVs) in the human genome remains challenging, and there is a growing interest to understand somatic SVs occurring in cancer, a disease of the genome. A havoc-causing SV process known as chromothripsis scars the genome when localized chromosome shattering and repair occur in a one-off catastrophe. Recent efforts led to the development of a set of conceptual criteria for the inference of chromothripsis events in cancer genomes and to the development of experimental model systems for studying this striking DNA alteration process in vitro. We discuss these approaches, and additionally touch upon current "Big Data" efforts that employ hybrid cloud computing to enable studies of numerous cancer genomes in an effort to search for commonalities and differences in molecular DNA alteration processes in cancer.

  16. Molecular mechanisms of curcumin and its semisynthetic analogues in prostate cancer prevention and treatment.

    Science.gov (United States)

    Jordan, Brian C; Mock, Charlotta D; Thilagavathi, Ramasamy; Selvam, Chelliah

    2016-05-01

    Primary prostate cancer, also known as prostate adenocarcinoma (PCa), is a devastating cancer in men worldwide. Europe and developing countries of Asia have fewer reported cases of prostate cancer compared to increasing cases in the United States with higher incidence in Black men. Risk factors associated with prostate cancer are aging, genetics, lifestyle, high body mass index as well as carcinogenic exposure to carbon-containing fuels, tobacco, and charbroiled meats. Hormone therapy and radical prostatectomy are commonly implemented treatments. The >20.000 prostate cancer deaths of 2013 suggest that there exists a need for enhanced chemopreventive and therapeutic agents for prostate cancer treatment. Fruits, vegetables, and red wines contain high levels of polyphenolic levels. Consumption of these products may provide chemoprevetion of PCa. Curcumin, the major compound from the turmeric rhizome Curcuma longa has long been used for medicinal purposes as an antiseptic and wound healing. This review focuses on curcumin's therapeutic effectiveness in vitro and in vivo in prostate cancer models. The review will highlight the mechanisms of actions of curcumin in the signaling pathways of prostate cancer. PMID:27018446

  17. In Vivo Anti-Cancer Mechanism of Low-Molecular-Weight Fucosylated Chondroitin Sulfate (LFCS) from Sea Cucumber Cucumaria frondosa

    OpenAIRE

    Xiaoxiao Liu; Yong Liu; Jiejie Hao; Xiaoliang Zhao; Yinzhi Lang; Fei Fan; Chao Cai; Guoyun Li; Lijuan Zhang; Guangli Yu

    2016-01-01

    The low-molecular-weight fucosylated chondroitin sulfate (LFCS) was prepared from native fucosylated chondroitin sulfate (FCS), which was extracted and isolated from sea cucumber Cucumaria frondosa, and the anti-cancer mechanism of LFCS on mouse Lewis lung carcinoma (LLC) was investigated. The results showed that LFCS remarkably inhibited LLC growth and metastasis in a dose-dependent manner. LFCS induced cell cycle arrest by increasing p53/p21 expression and apoptosis through activation of ca...

  18. Chinese Medicines Induce Cell Death: The Molecular and Cellular Mechanisms for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Xuanbin Wang

    2014-01-01

    Full Text Available Chinese medicines have long history in treating cancer. With the growing scientific evidence of biomedical researches and clinical trials in cancer therapy, they are increasingly accepted as a complementary and alternative treatment. One of the mechanisms is to induce cancer cell death. Aim. To comprehensively review the publications concerning cancer cell death induced by Chinese medicines in recent years and provide insights on anticancer drug discovery from Chinese medicines. Materials and Methods. Chinese medicines (including Chinese medicinal herbs, animal parts, and minerals were used in the study. The key words including “cancer”, “cell death”, “apoptosis”, “autophagy,” “necrosis,” and “Chinese medicine” were used in retrieval of related information from PubMed and other databases. Results. The cell death induced by Chinese medicines is described as apoptotic, autophagic, or necrotic cell death and other types with an emphasis on their mechanisms of anticancer action. The relationship among different types of cell death induced by Chinese medicines is critically reviewed and discussed. Conclusions. This review summarizes that CMs treatment could induce multiple pathways leading to cancer cell death, in which apoptosis is the dominant type. To apply these preclinical researches to clinic application will be a key issue in the future.

  19. Helicobacter pylori eradication to prevent gastric cancer:underlying molecular and cellular mechanisms

    Institute of Scientific and Technical Information of China (English)

    Shingo Tsuji; Norio Hayashi; Masahiko Tsujii; Hiroaki Murata; Tsutomu Nishida; Masato Komori; Masakazu Yasumaru; Shuji Ishii; Yoshiaki Sasayama; Sunao Kawano

    2006-01-01

    Numerous cellular and molecular events have been described in development of gastric cancer. In this article,we overviewed roles of Helicobacter pylori(H pylori) infection on some of the important events in gastric carcinogenesis and discussed whether these cellular and molecular events are reversible after cure of the infection. There are several bacterial components affecting gastric epithelial kinetics and promotion of gastric carcinogenesis. The bacterium also increases risks of genetic instability and mutations due to NO and other reactive oxygen species. Epigenetic silencing of tumor suppressor genes such as RUNX3 may alter the frequency of phenotype change of gastric glands to those with intestinal metaplasia. Host factors such as increased expression of growth factors, cytokines and COX-2 have been also reported in non-cancerous tissue in H pylori-positive subjects. It is noteworthy that most of the above phenomena are reversed after the cure of the infection. However,some of them including overexpression of COX-2 continue to exist and may increase risks for carcinogenesis in metaplastic or dysplastic mucosa even after successful H pylori eradication. Thus, H pylori eradication may not completely abolish the risk for gastric carcinogenesis. Efficiency of the cure of the infection in suppressing gastric cancer depends on the timing and the target population,and warrant further investigation.

  20. [Correlation between histological and molecular mechanisms of carcinogenesis in stomach cancer].

    Science.gov (United States)

    Rüschoff, J; Mehringer, S; Beyser, K; Dietmaier, W; Langner, C; Bocker, T; Kullmann, F

    1999-01-01

    Since gastric cancer is an exceptional heterogeneous tumor conflicting results have been obtained about the relationship between genotype and phenotype. From the molecular point of view gastric carcinoma diffuse type forms a distinct entity which is microsatellite stable, has almost no p53 mutations and exhibits in at least half of the cases mutations in the E-cadherin gene. In contrast, all other gastric carcinomas comprise a heterogeneous group of which about one third exhibits microsatellite instability (MSI) but no p53 protein stabilization or gene mutations. These tumors are either of pure intestinal (glandular) type or show large solid (medullary) tumor cell clusters. Thereby, in sporadic gastric cancer MSI is caused by loss of hMLH1 expression due to hypermethylation of the promotor region rather than by mutation of the gene itself. Tumors that are microsatellite stable (MSS) and show p53 alterations are either intestinal (about 70%) or a mixed-type encompassing at least 5% glandular and poorly differentiated diffuse components (about 30%). Whereas pure diffuse type gastric cancer is unlikely to develop from intestinal type carcinoma, this may, however, be the case in some advanced mixed-type gastric cancers.

  1. Exploring mechanisms of diet-colon cancer associations through candidate molecular interaction networks

    DEFF Research Database (Denmark)

    Westergaard, David; Li, Jun; Jensen, Kasper;

    2014-01-01

    Background: Epidemiological studies in the recent years have investigated the relationship between dietary habits and disease risk demonstrating that diet has a direct effect on public health. Especially plant-based diets-fruits, vegetables and herbs-are known as a source of molecules with pharma......Background: Epidemiological studies in the recent years have investigated the relationship between dietary habits and disease risk demonstrating that diet has a direct effect on public health. Especially plant-based diets-fruits, vegetables and herbs-are known as a source of molecules......-nutrient interactions. Here, we used colon cancer as a proof-of-concept for understanding key regulatory sites of diet on the disease pathway. Results: We started from a unique vantage point by having a database of 158 plants positively associated to colon cancer reduction and their molecular composition (similar to 3......,500 unique compounds). We generated a comprehensive picture of the interaction profile of these edible and non-edible plants with a predefined candidate colon cancer target space consisting of similar to 1,900 proteins. This knowledge allowed us to study systematically the key components in colon cancer...

  2. Report of National Cancer Institute symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. I. Common molecular mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Borg, D.C.

    1984-01-01

    Some aspects of molecular mechanisms common to radiation and chemical carcinogenesis are discussed, particularly the DNA damage done by these agents. Emphasis is placed on epidemiological considerations and on dose-response models used in risk assessment to extrapolate from experimental data obtained at high doses to the effects from long-term, low-level exposures. 3 references, 6 figures. (ACR)

  3. Inhibitory effects and molecular mechanisms of tetrahydrocurcumin against human breast cancer MCF-7 cells

    Directory of Open Access Journals (Sweden)

    Xiao Han

    2016-02-01

    Full Text Available Background: Tetrahydrocurcumin (THC, an active metabolite of curcumin, has been reported to have similar biological effects to curcumin, but the mechanism of the antitumor activity of THC is still unclear. Methods: The present study was to investigate the antitumor effects and mechanism of THC in human breast cancer MCF-7 cells using the methods of MTT assay, LDH assay, flow cytometry analysis, and western blot assay. Results: THC was found to have markedly cytotoxic effect and antiproliferative activity against MCF-7 cells in a dose-dependent manner with the IC50 for 24 h of 107.8 μM. Flow cytometry analysis revealed that THC mediated the cell-cycle arrest at G0/G1 phase, and 32.8% of MCF-7 cells entered the early phase of apoptosis at 100 μM for 24 h. THC also dose-dependently led to apoptosis in MCF-7 cells via the mitochondrial pathway, as evidenced by the activation of caspase-3 and caspase-9, the elevation of intracellular ROS, a decrease in Bcl-2 and PARP expression, and an increase in Bax expression. Meanwhile, cytochrome C was released to cytosol and the loss of mitochondria membrane potential (Δψm was observed after THC treatment. Conclusion: THC is an excellent source of chemopreventive agents in the treatment of breast cancer and has excellent potential to be explored as antitumor precursor compound.

  4. In Vivo Anti-Cancer Mechanism of Low-Molecular-Weight Fucosylated Chondroitin Sulfate (LFCS) from Sea Cucumber Cucumaria frondosa.

    Science.gov (United States)

    Liu, Xiaoxiao; Liu, Yong; Hao, Jiejie; Zhao, Xiaoliang; Lang, Yinzhi; Fan, Fei; Cai, Chao; Li, Guoyun; Zhang, Lijuan; Yu, Guangli

    2016-01-01

    The low-molecular-weight fucosylated chondroitin sulfate (LFCS) was prepared from native fucosylated chondroitin sulfate (FCS), which was extracted and isolated from sea cucumber Cucumaria frondosa, and the anti-cancer mechanism of LFCS on mouse Lewis lung carcinoma (LLC) was investigated. The results showed that LFCS remarkably inhibited LLC growth and metastasis in a dose-dependent manner. LFCS induced cell cycle arrest by increasing p53/p21 expression and apoptosis through activation of caspase-3 activity in LLC cells. Meanwhile, LFCS suppressed the expression of vascular endothelial growth factor (VEGF), increased the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) and downregulated the matrix metalloproteinases (MMPs) level. Furthermore, LFCS significantly suppressed the activation of ERK1/2/p38 MAPK/NF-κB pathway, which played a prime role in expression of MMPs. All of these data indicate LFCS may be used as anti-cancer drug candidates and deserve further study. PMID:27187337

  5. In Vivo Anti-Cancer Mechanism of Low-Molecular-Weight Fucosylated Chondroitin Sulfate (LFCS from Sea Cucumber Cucumaria frondosa

    Directory of Open Access Journals (Sweden)

    Xiaoxiao Liu

    2016-05-01

    Full Text Available The low-molecular-weight fucosylated chondroitin sulfate (LFCS was prepared from native fucosylated chondroitin sulfate (FCS, which was extracted and isolated from sea cucumber Cucumaria frondosa, and the anti-cancer mechanism of LFCS on mouse Lewis lung carcinoma (LLC was investigated. The results showed that LFCS remarkably inhibited LLC growth and metastasis in a dose-dependent manner. LFCS induced cell cycle arrest by increasing p53/p21 expression and apoptosis through activation of caspase-3 activity in LLC cells. Meanwhile, LFCS suppressed the expression of vascular endothelial growth factor (VEGF, increased the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1 and downregulated the matrix metalloproteinases (MMPs level. Furthermore, LFCS significantly suppressed the activation of ERK1/2/p38 MAPK/NF-κB pathway, which played a prime role in expression of MMPs. All of these data indicate LFCS may be used as anti-cancer drug candidates and deserve further study.

  6. Distinct molecular mechanisms underlying clinically relevant subtypes of breast cancer: gene expression analyses across three different platforms

    Directory of Open Access Journals (Sweden)

    Naume Bjørn

    2006-05-01

    Full Text Available Abstract Background Gene expression profiling has been used to define molecular phenotypes of complex diseases such as breast cancer. The luminal A and basal-like subtypes have been repeatedly identified and validated as the two main subtypes out of a total of five molecular subtypes of breast cancer. These two are associated with distinctly different gene expression patterns and more importantly, a significant difference in clinical outcome. To further validate and more thoroughly characterize these two subtypes at the molecular level in tumors at an early stage, we report a gene expression profiling study using three different DNA microarray platforms. Results Expression data from 20 tumor biopsies of early stage breast carcinomas were generated on three different DNA microarray platforms; Applied Biosystems Human Genome Survey Microarrays, Stanford cDNA Microarrays and Agilent's Whole Human Genome Oligo Microarrays, and the resulting gene expression patterns were analyzed. Both unsupervised and supervised analyses identified the different clinically relevant subtypes of breast tumours, and the results were consistent across all three platforms. Gene classification and biological pathway analyses of the genes differentially expressed between the two main subtypes revealed different molecular mechanisms descriptive of the two expression-based subtypes: Signature genes of the luminal A subtype were over-represented by genes involved in fatty acid metabolism and steroid hormone-mediated signaling pathways, in particular estrogen receptor signaling, while signature genes of the basal-like subtype were over-represented by genes involved in cell proliferation and differentiation, p21-mediated pathway, and G1-S checkpoint of cell cycle-signaling pathways. A minimal set of 54 genes that best discriminated the two subtypes was identified using the combined data sets generated from the three different array platforms. These predictor genes were further

  7. The Role of Ovarian Sex Steroids in Metabolic Homeostasis, Obesity, and Postmenopausal Breast Cancer: Molecular Mechanisms and Therapeutic Implications

    Directory of Open Access Journals (Sweden)

    Viroj Boonyaratanakornkit

    2015-01-01

    Full Text Available Obese postmenopausal women have an increased risk of breast cancer and are likely to have a worse prognosis than nonobese postmenopausal women. The cessation of ovarian function after menopause results in withdrawal of ovarian sex steroid hormones, estrogen, and progesterone. Accumulating evidence suggests that the withdrawal of estrogen and progesterone causes homeostasis imbalances, including decreases in insulin sensitivity and leptin secretion and changes in glucose and lipid metabolism, resulting in a total reduction in energy expenditure. Together with a decrease in physical activity and consumption of a high fat diet, these factors significantly contribute to obesity in postmenopausal women. Obesity may contribute to breast cancer development through several mechanisms. Obesity causes localized inflammation, an increase in local estrogen production, and changes in cellular metabolism. In addition, obese women have a higher risk of insulin insensitivity, and an increase in insulin and other growth factor secretion. In this review, we describe our current understanding of the molecular actions of estrogen and progesterone and their contributions to cellular metabolism, obesity, inflammation, and postmenopausal breast cancer. We also discuss how modifications of estrogen and progesterone actions might be used as a therapeutic approach for obesity and postmenopausal breast cancer.

  8. Understanding the molecular mechanisms of cancer prevention by dietary phytochemicals: From experimental models to clinical trials.

    Science.gov (United States)

    Maru, Girish B; Hudlikar, Rasika R; Kumar, Gaurav; Gandhi, Khushboo; Mahimkar, Manoj B

    2016-02-26

    Chemoprevention is one of the cancer prevention approaches wherein natural/synthetic agent(s) are prescribed with the aim to delay or disrupt multiple pathways and processes involved at multiple steps, i.e., initiation, promotion, and progression of cancer. Amongst environmental chemopreventive compounds, diet/beverage-derived components are under evaluation, because of their long history of exposure to humans, high tolerability, low toxicity, and reported biological activities. This compilation briefly covers and compares the available evidence on chemopreventive efficacy and probable mechanism of chemoprevention by selected dietary phytochemicals (capsaicin, curcumin, diallyl sulphide, genistein, green/black tea polyphenols, indoles, lycopene, phenethyl isocyanate, resveratrol, retinoids and tocopherols) in experimental systems and clinical trials. All the dietary phytochemicals covered in this review have demonstrated chemopreventive efficacy against spontaneous or carcinogen-induced experimental tumors and/or associated biomarkers and processes in rodents at several organ sites. The observed anti-initiating, anti-promoting and anti-progression activity of dietary phytochemicals in carcinogen-induced experimental models involve phytochemical-mediated redox changes, modulation of enzymes and signaling kinases resulting to effects on multiple genes and cell signaling pathways. Results from clinical trials using these compounds have not shown them to be chemopreventive. This may be due to our: (1) inability to reproduce the exposure conditions, i.e., levels, complexity, other host and lifestyle factors; and (2) lack of understanding about the mechanisms of action and agent-mediated toxicity in several organs and physiological processes in the host. Current research efforts in addressing the issues of exposure conditions, bioavailability, toxicity and the mode of action of dietary phytochemicals may help address the reason for observed mismatch that may ultimately

  9. Molecular mechanism of chemoresistance by miR-215 in osteosarcoma and colon cancer cells

    Directory of Open Access Journals (Sweden)

    Formentini Andrea

    2010-04-01

    Full Text Available Abstract Background Translational control mediated by non-coding microRNAs (miRNAs plays a key role in the mechanism of cellular resistance to anti-cancer drug treatment. Dihydrofolate reductase (DHFR and thymidylate synthase (TYMS, TS are two of the most important targets for antifolate- and fluoropyrimidine-based chemotherapies in the past 50 years. In this study, we investigated the roles of miR-215 in the chemoresistance to DHFR inhibitor methotrexate (MTX and TS inhibitor Tomudex (TDX. Results The protein levels of both DHFR and TS were suppressed by miR-215 without the alteration of the target mRNA transcript levels. Interestingly, despite the down-regulation of DHFR and TS proteins, ectopic expression of miR-215 resulted in a decreased sensitivity to MTX and TDX. Paradoxically, gene-specific small-interfering RNAs (siRNAs against DHFR or TS had the opposite effect, increasing sensitivity to MTX and TDX. Further studies revealed that over-expression of miR-215 inhibited cell proliferation and triggered cell cycle arrest at G2 phase, and that this effect was accompanied by a p53-dependent up-regulation of p21. The inhibitory effect on cell proliferation was more pronounced in cell lines containing wild-type p53, but was not seen in cells transfected with siRNAs against DHFR or TS. Moreover, denticleless protein homolog (DTL, a cell cycle-regulated nuclear and centrosome protein, was confirmed to be one of the critical targets of miR-215, and knock-down of DTL by siRNA resulted in enhanced G2-arrest, p53 and p21 induction, and reduced cell proliferation. Additionally, cells subjected to siRNA against DTL exhibited increased chemoresistance to MTX and TDX. Endogenous miR-215 was elevated about 3-fold in CD133+HI/CD44+HI colon cancer stem cells that exhibit slow proliferating rate and chemoresistance compared to control bulk CD133+/CD44+ colon cancer cells. Conclusions Taken together, our results indicate that miR-215, through the suppression

  10. [RNA interference: biogenesis molecular mechanisms and its applications in cervical cancer].

    Science.gov (United States)

    Peralta-Zaragoza, Oscar; Bermúdez-Morales, Víctor Hugo; Madrid-Marina, Vicente

    2010-01-01

    RNAi (RNA interference) is a natural process by which eukaryotic cells silence gene expression through small interference RNAs (siRNA) which are complementary to messenger RNA (mRNA). In this process, the siRNA that are 21-25 nucleotides long and are known as microRNA (miRNA), either associate with the RNA-induced silencing complex (RISC), which targets and cleaves the complementary mRNAs by the endonucleolytic pathway, or repress the translation. It is also possible to silence exogenous gene expression during viral infections by using DNA templates to transcribe siRNA with properties that are identical to those of bioactive microRNA. Persistent human papillomavirus (HPV) infection is the main etiological agent during cervical cancer development and the HPV E6 and E7 oncogenes, which induce cellular transformation and immortalization, represent strategic targets to be silenced with siRNA. In several in vitro and in vivo studies, it has been demonstrated that the introduction of siRNA directed against the E6 and E7 oncogenes in human tumoral cervical cells transformed by HPV, leads to the efficient silencing of HPV E6 and E7 oncogene expression, which induces the accumulation of the products of the p53 and pRb tumor suppressor genes and activates the mechanism of programmed cell death by apoptosis; thus, the progression of the tumoral growth process may be prevented. The goal of this review is to analyze the microRNA biogenesis process in the silencing of gene expression and to discuss the different protocols for the use of siRNA as a potential gene therapy strategy for the treatment of cervical cancer. PMID:20415061

  11. The role of leptin in gastric cancer: Clinicopathologic features and molecular mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Nyeong [Department of Internal Medicine, Hanyang University College of Medicine, Seoul (Korea, Republic of); Choi, Ho Soon, E-mail: hschoi96@hanyang.ac.kr [Department of Internal Medicine, Hanyang University College of Medicine, Seoul (Korea, Republic of); Yang, Sun Young [Department of Internal Medicine, Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, Seoul (Korea, Republic of); Park, Hyun Ki; Lee, Young Yiul; Lee, Oh Young; Yoon, Byung Chul; Hahm, Joon Soo [Department of Internal Medicine, Hanyang University College of Medicine, Seoul (Korea, Republic of); Paik, Seung Sam [Pathology, Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2014-04-18

    Highlights: • Leptin and Ob-R are expressed in gastric adenoma and early and advanced cancer. • Leptin is more likely associated with differentiated gastric cancer or cardia cancer. • Leptin proliferates gastric cancer cells via activating the STAT3 and ERK1/2 pathways. - Abstract: Obesity is associated with certain types of cancer, including gastric cancer. However, it is still unclear whether obesity-related cytokine, leptin, is implicated in gastric cancer. Therefore, we aimed to investigate the role of leptin in gastric cancer. The expression of leptin and its receptor, Ob-R, was assessed by immunohistochemical staining and was compared in patients with gastric adenoma (n = 38), early gastric cancer (EGC) (n = 38), and advanced gastric cancer (AGC) (n = 38), as a function of their clinicopathological characteristics. Gastric cancer cell lines were studied to investigate the effects of leptin on the signal transducer and activator of transcription-3 (STAT3) and extracellular receptor kinase 1/2 (ERK1/2) signaling pathways using MTT assays, immunoblotting, and inhibition studies. Leptin was expressed in gastric adenomas (42.1%), EGCs (47.4%), and AGCs (43.4%). Ob-R expression tended to increase from gastric adenoma (2%), through EGC (8%), to AGC (18%). Leptin induced the proliferation of gastric cancer cells by activating STAT3 and ERK1/2 and up-regulating the expression of vascular endothelial growth factor (VEGF). Blocking Ob-R with pharmacological inhibitors and by RNAi decreased both the leptin-induced activation of STAT3 and ERK1/2 and the leptin-induced expression of VEGF. Leptin plays a role in gastric cancer by stimulating the proliferation of gastric cancer cells via activating the STAT3 and ERK1/2 pathways.

  12. Microcalcifications in breast cancer: novel insights into the molecular mechanism and functional consequence of mammary mineralisation

    Science.gov (United States)

    Cox, R F; Hernandez-Santana, A; Ramdass, S; McMahon, G; Harmey, J H; Morgan, M P

    2012-01-01

    Background: Mammographic microcalcifications represent one of the most reliable features of nonpalpable breast cancer yet remain largely unexplored and poorly understood. Methods: We report a novel model to investigate the in vitro mineralisation potential of a panel of mammary cell lines. Primary mammary tumours were produced by implanting tumourigenic cells into the mammary fat pads of female BALB/c mice. Results: Hydroxyapatite (HA) was deposited only by the tumourigenic cell lines, indicating mineralisation potential may be associated with cell phenotype in this in vitro model. We propose a mechanism for mammary mineralisation, which suggests that the balance between enhancers and inhibitors of physiological mineralisation are disrupted. Inhibition of alkaline phosphatase and phosphate transport prevented mineralisation, demonstrating that mineralisation is an active cell-mediated process. Hydroxyapatite was found to enhance in vitro tumour cell migration, while calcium oxalate had no effect, highlighting potential consequences of calcium deposition. In addition, HA was also deposited in primary mammary tumours produced by implanting the tumourigenic cells into the mammary fat pads of female BALB/c mice. Conclusion: This work indicates that formation of mammary HA is a cell-specific regulated process, which creates an osteomimetic niche potentially enhancing breast tumour progression. Our findings point to the cells mineralisation potential and the microenvironment regulating it, as a significant feature of breast tumour development. PMID:22233923

  13. Molecular Mechanisms by Which a Fucus vesiculosus Extract Mediates Cell Cycle Inhibition and Cell Death in Pancreatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ulf Geisen

    2015-07-01

    Full Text Available Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1. Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application.

  14. Molecular Mechanisms of Preeclampsia

    OpenAIRE

    Vitoratos, N.; Hassiakos, D.; C. Iavazzo

    2012-01-01

    Preeclampsia is one of the leading causes of maternal morbidity/mortality. The pathogenesis of preeclampsia is still under investigation. The aim of this paper is to present the molecular mechanisms implicating in the pathway leading to preeclampsia.

  15. Molecular mechanisms in gliomagenesis

    DEFF Research Database (Denmark)

    Hulleman, Esther; Helin, Kristian

    2005-01-01

    , in order to design novel therapies and treatments for GBM, research has recently intensified to identify the cellular and molecular mechanisms leading to GBM formation. Modeling of astrocytomas by genetic manipulation of mice suggests that deregulation of the pathways that control gliogenesis during normal......-scale genomics and proteomics in combination with relevant mouse models will most likely provide novel insights into the molecular mechanisms underlying glioma formation and will hopefully lead to development of treatment modalities for GBM....

  16. Molecular Mechanisms Contributing to Resistance to Tyrosine Kinase-Targeted Therapy for Non-Small Cell Lung Cancer

    International Nuclear Information System (INIS)

    One of the most important pathways in non-small cell lung cancer (NSCLC) is the epidermal growth factor receptor (EGFR) pathway. This pathway affects several crucial processes in tumor development and progression, including tumor cell proliferation, apoptosis regulation, angiogenesis, and metastatic invasion. Targeting EGFR is currently being intensely explored. We are witnessing the development of a number of potential molecular-inhibiting treatments for application in clinical oncology. In the last decade, the tyrosine kinase (TK) domain of the EGFR was identified in NSCLC patients, and it has responded very well with a dramatic clinical improvement to TK inhibitors such are gefitinib and erlotinib. Unfortunately, there were primary and/or secondary resistance to these treatments, as shown by clinical trials. Subsequent molecular biology studies provided some explanations for the drug resistance phenomenon. The molecular mechanisms of resistance need to be clarified. An in-depth understanding of these targeted-therapy resistance may help us explore new strategies for overcoming or reversing the resistance to these inhibitors for the future of NSCLC treatment

  17. Molecular phenotyping of human ovarian cancer stem cells unravels the mechanisms for repair and chemoresistance

    DEFF Research Database (Denmark)

    Alvero, Ayesha B; Chen, Rui; Fu, Han-Hsuan;

    2009-01-01

    A major burden in the treatment of ovarian cancer is the high percentage of recurrence and chemoresistance. Cancer stem cells (CSCs) provide a reservoir of cells that can self-renew, can maintain the tumor by generating differentiated cells [non-stem cells (non-CSCs)] which make up the bulk of th...

  18. Transcriptional networks controlling breast cancer metastasis : molecular mechanisms shaping the SOX4 response

    NARCIS (Netherlands)

    Vervoort, S.J.

    2015-01-01

    Breast cancer is the most commonly diagnosed cancer in women. Despite great improvements in diagnosis and treatment of this disease, mortality remains high due to the development of metastatic disease resulting in clinical relapse. The majority of current treatment options primarily target the prima

  19. Molecular mechanisms for inhibition of colon cancer cells by combined epigenetic-modulating epigallocatechin gallate and sodium butyrate

    Energy Technology Data Exchange (ETDEWEB)

    Saldanha, Sabita N., E-mail: sabivan@uab.edu [Department of Biology, University of Alabama at Birmingham, 175 Campbell Hall, 1300 University Boulevard, Birmingham, AL 35294 (United States); Department of Biological Sciences, Alabama State University, Montgomery, AL 36104 (United States); Kala, Rishabh [Department of Biology, University of Alabama at Birmingham, 175 Campbell Hall, 1300 University Boulevard, Birmingham, AL 35294 (United States); Tollefsbol, Trygve O., E-mail: trygve@uab.edu [Department of Biology, University of Alabama at Birmingham, 175 Campbell Hall, 1300 University Boulevard, Birmingham, AL 35294 (United States); Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Comprehensive Center for Healthy Aging, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Comprehensive Diabetes Research Center, University of Alabama at Birmingham, Birmingham, AL 35294 (United States)

    2014-05-15

    Bioactive compounds are considered safe and have been shown to alter genetic and epigenetic profiles of tumor cells. However, many of these changes have been reported at molecular concentrations higher than physiologically achievable levels. We investigated the role of the combinatorial effects of epigallocatechin gallate (EGCG), a predominant polyphenol in green tea, and sodium butyrate (NaB), a dietary microbial fermentation product of fiber, in the regulation of survivin, which is an overexpressed anti-apoptotic protein in colon cancer cells. For the first time, our study showed that the combination treatment induced apoptosis and cell cycle arrest in RKO, HCT-116 and HT-29 colorectal cancer cells. This was found to be regulated by the decrease in HDAC1, DNMT1, survivin and HDAC activity in all three cell lines. A G2/M arrest was observed for RKO and HCT-116 cells, and G1 arrest for HT-29 colorectal cancer cells for combinatorial treatment. Further experimentation of the molecular mechanisms in RKO colorectal cancer (CRC) cells revealed a p53-dependent induction of p21 and an increase in nuclear factor kappa B (NF-κB)-p65. An increase in double strand breaks as determined by gamma-H2A histone family member X (γ-H2AX) protein levels and induction of histone H3 hyperacetylation was also observed with the combination treatment. Further, we observed a decrease in global CpG methylation. Taken together, these findings suggest that at low and physiologically achievable concentrations, combinatorial EGCG and NaB are effective in promoting apoptosis, inducing cell cycle arrest and DNA-damage in CRC cells. - Highlights: • EGCG and NaB as a combination inhibits colorectal cancer cell proliferation. • The combination treatment induces DNA damage, G2/M and G1 arrest and apoptosis. • Survivin is effectively down-regulated by the combination treatment. • p21 and p53 expressions are induced by the combination treatment. • Epigenetic proteins DNMT1 and HDAC1 are

  20. Molecular mechanisms for inhibition of colon cancer cells by combined epigenetic-modulating epigallocatechin gallate and sodium butyrate

    International Nuclear Information System (INIS)

    Bioactive compounds are considered safe and have been shown to alter genetic and epigenetic profiles of tumor cells. However, many of these changes have been reported at molecular concentrations higher than physiologically achievable levels. We investigated the role of the combinatorial effects of epigallocatechin gallate (EGCG), a predominant polyphenol in green tea, and sodium butyrate (NaB), a dietary microbial fermentation product of fiber, in the regulation of survivin, which is an overexpressed anti-apoptotic protein in colon cancer cells. For the first time, our study showed that the combination treatment induced apoptosis and cell cycle arrest in RKO, HCT-116 and HT-29 colorectal cancer cells. This was found to be regulated by the decrease in HDAC1, DNMT1, survivin and HDAC activity in all three cell lines. A G2/M arrest was observed for RKO and HCT-116 cells, and G1 arrest for HT-29 colorectal cancer cells for combinatorial treatment. Further experimentation of the molecular mechanisms in RKO colorectal cancer (CRC) cells revealed a p53-dependent induction of p21 and an increase in nuclear factor kappa B (NF-κB)-p65. An increase in double strand breaks as determined by gamma-H2A histone family member X (γ-H2AX) protein levels and induction of histone H3 hyperacetylation was also observed with the combination treatment. Further, we observed a decrease in global CpG methylation. Taken together, these findings suggest that at low and physiologically achievable concentrations, combinatorial EGCG and NaB are effective in promoting apoptosis, inducing cell cycle arrest and DNA-damage in CRC cells. - Highlights: • EGCG and NaB as a combination inhibits colorectal cancer cell proliferation. • The combination treatment induces DNA damage, G2/M and G1 arrest and apoptosis. • Survivin is effectively down-regulated by the combination treatment. • p21 and p53 expressions are induced by the combination treatment. • Epigenetic proteins DNMT1 and HDAC1 are

  1. Current Molecular Targeted Therapy in Advanced Gastric Cancer: A Comprehensive Review of Therapeutic Mechanism, Clinical Trials, and Practical Application

    Directory of Open Access Journals (Sweden)

    Kaichun Li

    2016-01-01

    Full Text Available Despite the great progress in the treatment of gastric cancer, it is still the third leading cause of cancer death worldwide. Patients often miss the opportunity for a surgical cure, because the cancer has already developed into advanced cancer when identified. Compared to best supportive care, chemotherapy can improve quality of life and prolong survival time, but the overall survival is often short. Due to the molecular study of gastric cancer, new molecular targeted drugs have entered the clinical use. Trastuzumab, an antibody targeting human epidermal growth factor receptor 2 (HER2, can significantly improve survival in advanced gastric cancer patients with HER2 overexpression. Second-line treatment of advanced gastric cancer with ramucirumab, an antibody targeting VEGFR-2, alone or in combination with paclitaxel, has been proved to provide a beneficial effect. The VEGFR-2 tyrosine kinase inhibitor, apatinib, can improve the survival of advanced gastric cancer patients after second-line chemotherapy failure. Unfortunately, none of the EGFR targeting antibodies (cetuximab or panitumumab, VEGF targeting monoclonal antibodies (bevacizumab, mTOR inhibitor (everolimus, or HGF/MET pathway targeting drugs has a significant survival benefit. Many other clinical trials based on molecular markers are underway. This review will summarize targeted therapies for advanced gastric cancer.

  2. Analysis of Somatic Mutations in Cancer: Molecular Mechanisms of Activation in the ErbB Family of Receptor Tyrosine Kinases

    International Nuclear Information System (INIS)

    The ErbB/EGFR/HER family of kinases consists of four homologous receptor tyrosine kinases which are important regulatory elements in many cellular processes, including cell proliferation, differentiation, and migration. Somatic mutations in, or over-expression of, the ErbB family is found in many cancers and is correlated with a poor prognosis; particularly, clinically identified mutations found in non-small-cell lung cancer (NSCLC) of ErbB1 have been shown to increase its basal kinase activity and patients carrying these mutations respond remarkably to the small tyrosine kinase inhibitor gefitinib. Here, we analyze the potential effects of the currently catalogued clinically identified mutations in the ErbB family kinase domains on the molecular mechanisms of kinase activation. Recently, we identified conserved networks of hydrophilic and hydrophobic interactions characteristic to the active and inactive conformation, respectively. Here, we show that the clinically identified mutants influence the kinase activity in distinctive fashion by affecting the characteristic interaction networks

  3. Combined therapeutic effect and molecular mechanisms of metformin and cisplatin in human lung cancer xenografts in nude mice

    Directory of Open Access Journals (Sweden)

    Yu-Qin Chen

    2015-01-01

    Full Text Available Objective: This work was aimed at studying the inhibitory activity of metformin combined with the commonly used chemotherapy drug cisplatin in human lung cancer xenografts in nude mice. We also examined the combined effects of these drugs on the molecular expression of survivin, matrix metalloproteinase-2 (MMP-2, vascular endothelial growth factor-C (VEGF-C, and vascular endothelial growth factorreceptor-3 (VEGFR-3 to determine the mechanism of action and to explore the potential applications of the new effective drug therapy in lung cancer. Materials and Methods: The nude mice model of lung cancer xenografts was established, and mice were randomly divided into the metformin group, the cisplatin group, the metformin + cisplatin group, and the control group. The animals were killed 42 days after drug administration, and the tumor tissues were then sampled to detect the messenger ribonucleic acid (mRNA and protein expression levels of survivin, MMP-2, VEGF-C, and VEGFR-3 by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR. Results: The protein and mRNA expression levels of survivin, MMP-2, VEGF-C, and VEGFR-3 in the cisplatin group and the combined treatment group were lower than that in the control group (P < 0.05. In the metformin group, the expression of MMP-2 protein and mRNA was lower than that in the control group (P < 0.05. The protein and mRNA expression levels of survivin, MMP-2, VEGF-C, and VEGFR-3 in the combined treatment group were lower than that in the cisplatin group and the metformin group (P < 0.05. Conclusions: Metformin inhibited the expression of MMP-2, cisplatin and the combined treatment inhibited the expression of survivin, MMP-2, VEGF-C, and VEGFR-3, and the combined treatment of metformin with cisplatin resulted in enhanced anti-tumor efficacy.

  4. Change of the cell cycle after flutamide treatment in prostate cancer cells and its molecular mechanism

    Institute of Scientific and Technical Information of China (English)

    Yong Wang; Wei-Jun Qin; He Wang; Guo-Xing Shao; Chen Shao; Chang-Hong Shi; Lei Zhang; Hong-Hong Yue; Peng-Fei Wang; Bo Yang; Yun-Tao Zhang; Fan Liu

    2005-01-01

    Aim: To explore the effect of androgen receptor (AR) on the expression of the cell cycle-related genes, such as CDKN1A and BTG1, in prostate cancer cell line LNCaP. Methods: After AR antagonist flutamide treatment and confirmation of its effect by phase contrast microscope and flow cytometry, the differential expression of the cell cycle-related genes was analyzed by a cDNA microarray. The flutamide treated cells were set as the experimental group and the LNCaP cells as the control. We labeled cDNA probes of the experimental group and control group with Cy5 and Cy3 dyes, respectively, through reverse transcription. Then we hybridized the cDNA probes with cDNA microarrays, which contained 8 126 unique human cDNA sequences and the chip was scanned to get the fluorescent values of Cy5 and Cy3 on each spot. After primary analysis, reverse transcription polymerase chain reaction (RTPCR) tests were carried out to confirm the results of the chips. Results:After AR antagonist flutamide treatment,three hundred and twenty-six genes (3.93 %) expressed differentially, 97 down-regulated and 219 up-regulated.Among them, eight up-regulated genes might be cell cycle-related, namely CDC10, NRAS, BTG1, Weel, CLK3,DKFZP564A122, CDKN1A and BTG2. The CDKN1A and BTG1 gene mRNA expression was confirmed to be higher in the experimental group by RT-PCR, whilep53 mRNA expression had no significant changes. Conclusion: Flutamide treatment might up-regulate CDKN1A and BTG1 expression in prostate cancer cells. The protein expressions of CDKN1A and BTG1 play an important role in inhibiting the proliferation of cancer cells. CDKN1A has a great impact on the cell cycle of prostate cancer cells and may play a role in the cancer cells in a p53-independent pathway. The prostate cancer cells might affect the cell cycle-related genes by activating AR and thus break the cell cycle control.

  5. Molecular mechanisms controlling asymmetric and symmetric self-renewal of cancer stem cells

    OpenAIRE

    Yoo, Young Dong; Kwon, Yong Tae

    2015-01-01

    Cancer stem cells (CSCs), or alternatively called tumor initiating cells (TICs), are a subpopulation of tumor cells, which possesses the ability to self-renew and differentiate into bulk tumor mass. An accumulating body of evidence suggests that CSCs contribute to the growth and recurrence of tumors and the resistance to chemo- and radiotherapy. CSCs achieve self-renewal through asymmetric division, in which one daughter cell retains the self-renewal ability, and the other is destined to diff...

  6. Non-small-cell lung cancer: molecular targeted therapy and personalized medicine – drug resistance, mechanisms, and strategies

    Directory of Open Access Journals (Sweden)

    Sechler M

    2013-04-01

    Full Text Available Marybeth Sechler,1,2 Amber D Cizmic,3 Sreedevi Avasarala,1 Michelle Van Scoyk,1 Christine Brzezinski,1 Nicole Kelley,1 Rama Kamesh Bikkavilli,1 Robert A Winn1–3 1Division of Pulmonary Sciences and Critical Care, 2Program in Cancer Biology, University of Colorado, Aurora, CO, USA; 3Veterans Affairs Medical Center, Denver, CO, USA Abstract: Targeted therapies for cancer bring the hope of specific treatment, providing high efficacy and in some cases lower toxicity than conventional treatment. Although targeted therapeutics have helped immensely in the treatment of several cancers, like chronic myelogenous leukemia, colon cancer, and breast cancer, the benefit of these agents in the treatment of lung cancer remains limited, in part due to the development of drug resistance. In this review, we discuss the mechanisms of drug resistance and the current strategies used to treat lung cancer. A better understanding of these drug-resistance mechanisms could potentially benefit from the development of a more robust personalized medicine approach for the treatment of lung cancer. Keywords: lung cancer, drug targets, personalized medicine, NSCLC

  7. Glycoprotein mucin molecular brush on cancer cell surface acting as mechanical barrier against drug delivery

    Science.gov (United States)

    Wang, Xin; Shah, Aalok A.; Campbell, Robert B.; Wan, Kai-tak

    2010-12-01

    Uptake of cytotoxic drugs by typical tumor cells is limited by the dense dendritic network of oligosaccharide mucin chains that forms a mechanical barrier. Atomic force microscopy is used to directly measure the force needed to pierce the mucin layer to reach the cell surface. Measurements are analyzed by de Gennes' steric reptation theory. Multidrug resistant ovarian tumor cells shows significantly larger penetration load compared to the wide type. A pool of pancreatic, lung, colorectal, and breast cells are also characterized. The chemotherapeutic agent, benzyl-α-GalNac, for inhibiting glycosylation is shown to be effective in reducing the mechanical barrier.

  8. Molecular biology of pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Miroslav Zavoral; Petra Minarikova; Filip Zavada; Cyril Salek; Marek Minarik

    2011-01-01

    In spite of continuous research efforts directed at early detection and treatment of pancreatic cancer, the outlook for patients affected by the disease remains dismal. With most cases still being diagnosed at advanced stages, no improvement in survival prognosis is achieved with current diagnostic imaging approaches. In the absence of a dominant precancerous condition, several risk factors have been identified including family history, chronic pancreatitis, smoking, diabetes mellitus, as well as certain genetic disorders such as hereditary pancreatitis, cystic fibrosis, familial atypical multiple Most pancreatic carcinomas, however, remain sporadic. Current progress in experimental molecular techniques has enabled detailed understanding of the molecular processes of pancreatic cancer development. According to the latest information, malignant pancreatic transformation involves multiple oncogenes and tumor-suppressor genes that are involved in a variety of signaling pathways. The most characteristic aberrations (somatic point mutations and allelic losses) affect oncogenes and tumor-suppressor genes within RAS, AKT and Wnt signaling, and have a key role in transcription and proliferation, as well as systems that regulate the cell cycle (SMAD/DPC, CDKN2A/p16) and apoptosis (TP53). Understanding of the underlying molecular mechanisms should promote development of new methodology for early diagnosis and facilitate improvement in current approaches for pancreatic cancer treatment.

  9. Advances in the Molecular Mechanisms and Prognostic Significance of EMT 
in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Qinchen CAO

    2014-07-01

    Full Text Available Epithelial to mesenchymal transition (EMT has an important role in the development of embryo, as well as that in the metastasis of non-small cell lung cancer (NSCLC. Recent researches have demonstrated that both morphological and phenotypic conversions emerge in cells undergoing EMT. As most of relevant studies were on other cancers, it is essential to uncover whether it is the similar mechanisms accounting for EMT in NSCLC. With the progress of the studies, EMT-related basic researches are gradually applied to predicting the prognosis of NSCLC. The aim of this article was to discuss the mechanisms related to EMT emerging in NSCLC.

  10. The molecular biology of cancer.

    Science.gov (United States)

    Bertram, J S

    2000-12-01

    The process by which normal cells become progressively transformed to malignancy is now known to require the sequential acquisition of mutations which arise as a consequence of damage to the genome. This damage can be the result of endogenous processes such as errors in replication of DNA, the intrinsic chemical instability of certain DNA bases or from attack by free radicals generated during metabolism. DNA damage can also result from interactions with exogenous agents such as ionizing radiation, UV radiation and chemical carcinogens. Cells have evolved means to repair such damage, but for various reasons errors occur and permanent changes in the genome, mutations, are introduced. Some inactivating mutations occur in genes responsible for maintaining genomic integrity facilitating the acquisition of additional mutations. This review seeks first to identify sources of mutational damage so as to identify the basic causes of human cancer. Through an understanding of cause, prevention may be possible. The evolution of the normal cell to a malignant one involves processes by which genes involved in normal homeostatic mechanisms that control proliferation and cell death suffer mutational damage which results in the activation of genes stimulating proliferation or protection against cell death, the oncogenes, and the inactivation of genes which would normally inhibit proliferation, the tumor suppressor genes. Finally, having overcome normal controls on cell birth and cell death, an aspiring cancer cell faces two new challenges: it must overcome replicative senescence and become immortal and it must obtain adequate supplies of nutrients and oxygen to maintain this high rate of proliferation. This review examines the process of the sequential acquisition of mutations from the prospective of Darwinian evolution. Here, the fittest cell is one that survives to form a new population of genetically distinct cells, the tumor. This review does not attempt to be comprehensive but

  11. Mechanisms of cancer metastasis to the bone

    Institute of Scientific and Technical Information of China (English)

    Juan Juan YIN; Claire B. POLLOCK; Kathleen KELLY

    2005-01-01

    Some of the most common human cancers, including breast cancer, prostate cancer, and lung cancer, metastasize with avidity to bone. What is the basis for their preferential growth within the bone microenvironment? Bidirectional interactions between tumor cells and cells that make up bone result in a selective advantage for tumor growth and can lead to bone destruction or new bone matrix deposition. This review discusses our current understanding of the molecular components and mechanisms that are responsible for those interactions.

  12. Breast cancer heterogeneity: mechanisms, proofs, and implications

    OpenAIRE

    Yi-Hsuan Hsiao, Ming-Chih Chou, Carol Fowler, Jeffrey T. Mason, Yan-gao Man

    2010-01-01

    Human breast cancer represents a group of highly heterogeneous lesions consisting of about 20 morphologically distinct subtypes with substantially different molecular and/or biochemical signatures, clinical courses, and prognoses. This study analyzed the possible correlation between the morphological presentations of breast cancer and two hypothesized models of carcinogenesis, in order to identify the intrinsic mechanism(s) and clinical implications of breast cancer heterogeneity.

  13. Breast cancer heterogeneity: mechanisms, proofs, and implications

    Directory of Open Access Journals (Sweden)

    Yi-Hsuan Hsiao, Ming-Chih Chou, Carol Fowler, Jeffrey T. Mason, Yan-gao Man

    2010-01-01

    Full Text Available Human breast cancer represents a group of highly heterogeneous lesions consisting of about 20 morphologically distinct subtypes with substantially different molecular and/or biochemical signatures, clinical courses, and prognoses. This study analyzed the possible correlation between the morphological presentations of breast cancer and two hypothesized models of carcinogenesis, in order to identify the intrinsic mechanism(s and clinical implications of breast cancer heterogeneity.

  14. 乳腺癌骨转移分子机制研究进展%Research progress on the molecular mechanism of breast cancer bone metastasis

    Institute of Scientific and Technical Information of China (English)

    曾慧娟(综述); 王少华(审校)

    2015-01-01

    Breast cancer is one of the most common malignant tumors in women. Bone is commonly affected in the context of metastatic breast cancer.Once bone metastasis happens, patient would experience poor prognosis and impaired quality of life.However, there is a lack of approaches for more sensitive and specific diagnosis and treatments for breast cancer bone metastasis.Thus, it is im-perative to find new treatment target from molecular mechanism.In this paper, we review the current research progress on the molecular mechanism from several levels including gene profile, proteins and microRNAs.We also review the establishment of animal models of breast cancer bone metastasis.With the achievements acquired in the completed or undergoing researches on breast cancer bone metasta-sis, we hope the finding of the optimal diagnostic and therapeutic targets could lead the breast cancer research into a new era.%乳腺癌是女性最常见的恶性肿瘤之一,骨为其最易发生转移的部位。一旦发生骨转移,患者预后及生活质量明显下降,然而目前仍缺乏有力证据证实的、能够应用于临床的特异性诊疗手段。因此,迫切需要从其分子机制入手,寻找新的分子靶点。文中就乳腺癌骨转移在基因、蛋白及miRNA3个层面机制的研究进展作一综述,并阐述了乳腺癌骨转移动物模型的建立方法。

  15. Biological Significance and the Related Molecular Mechanism of Ets1 mRNA Expression in Lung Cancer by Tissue Microarray (TMA)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To investigate the expressions and molecular mechanism of Ets-1 mRNA, and TGFβ1 and c-Met proteins in the pathogenesis, progression of lung cancer by tissue microarray (TMA) method. Methods: The expressions of Ets-1 mRNA, and TGFβ1 and c-Met proteins were detected in 89 primary lung cancers, 12 lung cancer with lymph-node metastasis and 12 precancerous lesions by FISH(fluorescence in situ hybridization) and immunohistochemical method, and 10 normal lung tissues were used as controls. Results: The expressions of Ets-1 mRNA, and TGFβ1 and c-Met proteins were significantly higher in 89 primary lung cancer than in the control group (P<0.05). The expressions of Ets-1 mRNA, and TGFβ1 and c-Met proteins were related to lymph node metastasis and clinical stages. There was a positive correlation between the Ets-1 mRNA expression and TGFβ1 and c-Met proteins (P<0.05). Conclusion: Ets-1 mRNA, TGFβ1 and c-Met proteins may be related to the pathogenesis, progression and malignant behavior of lung cancer. They may play an important role in prognosis assessment of lung cancer.

  16. In silico analysis of molecular mechanisms of Galanthus nivalis agglutinin-related lectin-induced cancer cell death from carbohydrate-binding motif evolution hypothesis.

    Science.gov (United States)

    Yu, Qi-Jia; Li, Zi-Yue; Yao, Shun; Ming, Miao; Wang, Shu-Ya; Liu, Bo; Bao, Jin-Ku

    2011-10-01

    Galanthus nivalis agglutinin-related lectins, a superfamily of strictly mannose-binding-specific lectins widespread amongst monotyledonous plants, have drawn a rising attention for their remarkable anti-proliferative and apoptosis-inducing activities toward various types of cancer cells; however, the precise molecular mechanisms by which they induce tumor cell apoptosis are still only rudimentarily understood. Herein, we found that the three conserved motifs "QXDXNXVXY," the mannose-specific binding sites, could mutate at one or more amino acid sites, which might be a driving force for the sequential evolution and thus ultimately leading to the complete disappearance of the three conserved motifs. In addition, we found that the motif evolution could result in the diversification of sugar-binding types that G. nivalis agglutinin-related lectins could bind from specific mannose receptors to more types of sugar-containing receptors in cancer cells. Subsequently, we indicated that some sugar-containing receptors such as TNFR1, EGFR, Hsp90, and Hsp70 could block downstream anti-apoptotic or survival signaling pathways, which, in turn, resulted in tumor cell apoptosis. Taken together, our hypothesis that carbohydrate-binding motif evolution may impact the G. nivalis agglutinin-related lectin-induced survival or anti-apoptotic pathways would provide a new perspective for further elucidating the intricate relationships between the carbohydrate-binding specificities and complex molecular mechanisms by which G. nivalis agglutinin-related lectins induce cancer cell death.

  17. Molecular and genetic bases of pancreatic cancer.

    Science.gov (United States)

    Vaccaro, Vanja; Gelibter, Alain; Bria, Emilio; Iapicca, Pierluigi; Cappello, Paola; Di Modugno, Francesca; Pino, Maria Simona; Nuzzo, Carmen; Cognetti, Francesco; Novelli, Francesco; Nistico, Paola; Milella, Michele

    2012-06-01

    Pancreatic cancer remains a formidable challenge for oncologists and patients alike. Despite intensive efforts, attempts at improving survival in the past 15 years, particularly in advanced disease, have failed. This is true even with the introduction of molecularly targeted agents, chosen on the basis of their action on pathways that were supposedly important in pancreatic cancer development and progression: indeed, with the notable exception of the epidermal growth factor receptor (EGFR) inhibitor erlotinib, that has provided a minimal survival improvement when added to gemcitabine, other agents targeting EGFR, matrix metallo-proteases, farnesyl transferase, or vascular endothelial growth factor have not succeeded in improving outcomes over standard gemcitabine monotherapy for a variety of different reasons. However, recent developments in the molecular epidemiology of pancreatic cancer and an ever evolving understanding of the molecular mechanisms underlying pancreatic cancer initiation and progression raise renewed hope to find novel, relevant therapeutic targets that could be pursued in the clinical setting. In this review we focus on molecular epidemiology of pancreatic cancer, epithelial-to-mesenchymal transition and its influence on sensitivity to EGFR-targeted approaches, apoptotic pathways, hypoxia-related pathways, developmental pathways (such as the hedgehog and Notch pathways), and proteomic analysis as keys to a better understanding of pancreatic cancer biology and, most importantly, as a source of novel molecular targets to be exploited therapeutically.

  18. [Colorectal cancer (CCR): genetic and molecular alterations].

    Science.gov (United States)

    Juárez-Vázquez, Clara Ibet; Rosales-Reynoso, Mónica Alejandra

    2014-01-01

    The aim of this review is to present a genetic and molecular overview of colorectal carcinogenesis (sporadic and hereditary origin) as a multistage process, where there are a number of molecular mechanisms associated with the development of colorectal cancer and genomic instability that allows the accumulation of mutations in proto-oncogenes and tumor suppressor genes, chromosomal instability, and methylation and microsatellite instability, and the involvement of altered expression of microRNAs' prognosis factors.

  19. Molecular therapeutics in pancreas cancer.

    Science.gov (United States)

    Narayanan, Vignesh; Weekes, Colin D

    2016-04-15

    The emergence of the "precision-medicine" paradigm in oncology has ushered in tremendous improvements in patient outcomes in a wide variety of malignancies. However, pancreas ductal adenocarcinoma (PDAC) has remained an obstinate challenge to the oncology community and continues to be associated with a dismal prognosis with 5-year survival rates consistently less than 5%. Cytotoxic chemotherapy with gemcitabine-based regimens has been the cornerstone of treatment in PDAC especially because most patients present with inoperable disease. But in recent years remarkable basic science research has improved our understanding of the molecular and genetic basis of PDAC. Whole genomic analysis has exemplified the genetic heterogeneity of pancreas cancer and has led to ingenious efforts to target oncogenes and their downstream signaling cascades. Novel stromal depletion strategies have been devised based on our enhanced recognition of the complex architecture of the tumor stroma and the various mechanisms in the tumor microenvironment that sustain tumorigenesis. Immunotherapy using vaccines and immune checkpoint inhibitors has also risen to the forefront of therapeutic strategies against PDAC. Furthermore, adoptive T cell transfer and strategies to target epigenetic regulators are being explored with enthusiasm. This review will focus on the recent advances in molecularly targeted therapies in PDAC and offer future perspectives to tackle this lethal disease. PMID:27096032

  20. Molecular imaging in ovarian cancer.

    Science.gov (United States)

    Reyners, A K L; Broekman, K E; Glaudemans, A W J M; Brouwers, A H; Arts, H J G; van der Zee, A G J; de Vries, E G E; Jalving, M

    2016-04-01

    Ovarian cancer has a high mortality and novel-targeted treatment strategies have not resulted in breakthroughs for this disease. Insight into the molecular characteristics of ovarian tumors may improve diagnosis and selection of patients for treatment with targeted therapies. A potential way to achieve this is by means of molecular imaging. Generic tumor processes, such as glucose metabolism ((18)F-fluorodeoxyglucose) and DNA synthesis ((18)F-fluorodeoxythymidine), can be visualized non-invasively. More specific targets, such as hormone receptors, growth factor receptors, growth factors and targets of immunotherapy, can also be visualized. Molecular imaging can capture data on intra-patient tumor heterogeneity and is of potential value for individualized, target-guided treatment selection. Early changes in molecular characteristics during therapy may serve as early predictors of response. In this review, we describe the current knowledge on molecular imaging in the diagnosis and as an upfront or early predictive biomarker in patients with ovarian cancer. PMID:27141066

  1. Molecular mechanisms of paclitaxel and NM-3 on human gastric cancer in a severe combined immune deficiency mice orthotopic implantation model

    Institute of Scientific and Technical Information of China (English)

    Jin-Shui Zhu; Ming-Quan Song; Guo-Qiang Chen; Qin Li; Qun Sun; Qiang Zhang

    2007-01-01

    AIM: To explore the molecular mechanisms of action of paclitaxel and NM-3 on human gastric cancer in severe combined immune deficiency (SCID) mice.METHODS: Human gastric cancer cells SGC-7901 were implanted into SCID mice and mice were treated with paclitaxel and NM-3. The effects of paclitaxel and NM-3 on apoptosis of human gastric cancer cells were analyzed using flow cytometry, TUNEL assays, and DNA fragment analyses.RESULTS: Apoptosis of SGC-7901 cells was successfully induced by paclitaxel, NM-3, and the combination of paclitaxel and NM-3 24 h after injection as shown by the presence of apoptotic hypodiploid peaks on the flow cytometer before G1-S and a characteristic apoptotic band pattern in the DNA electrophoresis. The apoptotic rate detected by TUNEL assay was found to be significantly higher in the paclitaxel/NM-3 compared to the control group (38.5% ± 5.14% vs 13.2% ± 1.75%,P < 0.01).CONCLUSION: Paclitaxel in combination with NM-3 is able to induce apoptosis of the human gastric cancer cells in SCID mice effectively and synergistically.

  2. Molecular imaging in cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, Mark H. [Stanford University School of Medicine, Stanford, CA (United States); Chen, Xiaoyuan [National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), Bethesda, MD (United States)

    2011-02-15

    The success of cancer therapy can be difficult to predict, as its efficacy is often predicated upon characteristics of the cancer, treatment, and individual that are not fully understood or are difficult to ascertain. Monitoring the response of disease to treatment is therefore essential and has traditionally been characterized by changes in tumor volume. However, in many instances, this singular measure is insufficient for predicting treatment effects on patient survival. Molecular imaging allows repeated in vivo measurement of many critical molecular features of neoplasm, such as metabolism, proliferation, angiogenesis, hypoxia, and apoptosis, which can be employed for monitoring therapeutic response. In this review, we examine the current methods for evaluating response to treatment and provide an overview of emerging PET molecular imaging methods that will help guide future cancer therapies. (orig.)

  3. Cancer Cell Fusion: Mechanisms Slowly Unravel

    Science.gov (United States)

    Noubissi, Felicite K.; Ogle, Brenda M.

    2016-01-01

    Although molecular mechanisms and signaling pathways driving invasion and metastasis have been studied for many years, the origin of the population of metastatic cells within the primary tumor is still not well understood. About a century ago, Aichel proposed that cancer cell fusion was a mechanism of cancer metastasis. This hypothesis gained some support over the years, and recently became the focus of many studies that revealed increasing evidence pointing to the possibility that cancer cell fusion probably gives rise to the metastatic phenotype by generating widespread genetic and epigenetic diversity, leading to the emergence of critical populations needed to evolve resistance to the treatment and development of metastasis. In this review, we will discuss the clinical relevance of cancer cell fusion, describe emerging mechanisms of cancer cell fusion, address why inhibiting cancer cell fusion could represent a critical line of attack to limit drug resistance and to prevent metastasis, and suggest one new modality for doing so. PMID:27657058

  4. Molecular genetics of colorectal cancer.

    Science.gov (United States)

    Bogaert, Julie; Prenen, Hans

    2014-01-01

    Approximately 90% of colorectal cancer cases are sporadic without family history or genetic predisposition, while in less than 10% a causative genetic event has been identified. Historically, colorectal cancer classification was only based on clinical and pathological features. Many efforts have been made to discover the genetic and molecular features of colorectal cancer, and there is more and more evidence that these features determine the prognosis and response to (targeted) treatment. Colorectal cancer is a heterogeneous disease, with three known major molecular groups. The most common is the chromosomal instable group, characterized by an accumulation of mutations in specific oncogenes and tumor suppressor genes. The second is the microsatellite instable group, caused by dysfunction of DNA mismatch repair genes leading to genetic hypermutability. The CpG Island Methylation phenotype is the third group, distinguished by hypermethylation. Colorectal cancer subtyping has also been addressed using genome-wide gene expression profiling in large patient cohorts and recently several molecular classification systems have been proposed. In this review we would like to provide an up-to-date overview of the genetic aspects of colorectal cancer. PMID:24714764

  5. Molecular mechanisms of meditation.

    Science.gov (United States)

    Jindal, Vishal; Gupta, Sorab; Das, Ritwik

    2013-12-01

    Meditation is a complex process involving change in cognition, memory, and social and emotional control, and causes improvement in various cardiovascular, neurological, autoimmune, and renal pathologies. Meditation also become widely used in medical and psychological treatment therapies for stress-related physical and mental disorders. But still, biological mechanisms in terms of effect on brain and body are poorly understood. This paper explains the basic changes due to meditation in cerebral cortex, prefrontal area, cingulate gyrus, neurotransmitters, white matter, autonomic nervous system, limbic system, cytokines, endorphins, hormones, etc. The following is a review of the current literature regarding the various neurophysiological mechanisms, neuro-endocrine mechanisms, neurochemical substrates, etc. that underlies the complex processes of meditation. PMID:23737355

  6. Molecular mechanisms of meditation.

    Science.gov (United States)

    Jindal, Vishal; Gupta, Sorab; Das, Ritwik

    2013-12-01

    Meditation is a complex process involving change in cognition, memory, and social and emotional control, and causes improvement in various cardiovascular, neurological, autoimmune, and renal pathologies. Meditation also become widely used in medical and psychological treatment therapies for stress-related physical and mental disorders. But still, biological mechanisms in terms of effect on brain and body are poorly understood. This paper explains the basic changes due to meditation in cerebral cortex, prefrontal area, cingulate gyrus, neurotransmitters, white matter, autonomic nervous system, limbic system, cytokines, endorphins, hormones, etc. The following is a review of the current literature regarding the various neurophysiological mechanisms, neuro-endocrine mechanisms, neurochemical substrates, etc. that underlies the complex processes of meditation.

  7. Molecular oncology of lung cancer.

    Science.gov (United States)

    Toyooka, Shinichi; Mitsudomi, Tetsuya; Soh, Junichi; Aokage, Keiju; Yamane, Masaomi; Oto, Takahiro; Kiura, Katsuyuki; Miyoshi, Shinichiro

    2011-08-01

    Progress in genetic engineering has made it possible to elucidate the molecular biological abnormalities in lung cancer. Mutations in KRAS and P53 genes, loss of specific alleles, and DNA methylation of the tumor suppressor genes were the major abnormalities investigated between 1980 and the 2000s. In 2004, mutations in the epidermal growth factor receptor (EGFR) gene that cause oncogene addiction were discovered in non-small-cell lung cancers (NSCLCs), especially in adenocarcinomas. Because they are strongly associated with sensitivity to EGFR-tyrosine kinase inhibitors (EGFR-TKIs), a great deal of knowledge has been acquired in regard to both EGFR and other genes in the EGFR family and their downstream genes. Moreover, in 2007 the existence of the echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) fusion gene was discovered in NSCLC; and the same as EGFR-TKIs, ALK inhibitors are being found to be highly effective in lung cancers that have this translocation. These discoveries graphically illustrate that molecular biological findings are directly linked to the development of clinical oncology and to improving the survival rates of lung cancer patients. Here, we review the remarkable progress in molecular biological knowledge acquired thus far in regard to lung cancer, especially NSCLC, and the future possibilities. PMID:21850578

  8. Molecular classification of gastric cancer.

    Science.gov (United States)

    Chia, N-Y; Tan, P

    2016-05-01

    Gastric cancer (GC), a heterogeneous disease characterized by epidemiologic and histopathologic differences across countries, is a leading cause of cancer-related death. Treatment of GC patients is currently suboptimal due to patients being commonly treated in a uniform fashion irrespective of disease subtype. With the advent of next-generation sequencing and other genomic technologies, GCs are now being investigated in great detail at the molecular level. High-throughput technologies now allow a comprehensive study of genomic and epigenomic alterations associated with GC. Gene mutations, chromosomal aberrations, differential gene expression and epigenetic alterations are some of the genetic/epigenetic influences on GC pathogenesis. In addition, integrative analyses of molecular profiling data have led to the identification of key dysregulated pathways and importantly, the establishment of GC molecular classifiers. Recently, The Cancer Genome Atlas (TCGA) network proposed a four subtype classification scheme for GC based on the underlying tumor molecular biology of each subtype. This landmark study, together with other studies, has expanded our understanding on the characteristics of GC at the molecular level. Such knowledge may improve the medical management of GC in the future. PMID:26861606

  9. Histone deacetylase inhibitors in castration-resistant prostate cancer: molecular mechanism of action and recent clinical trials

    OpenAIRE

    Kaushik, Dharam; Vashistha, Vishal; Isharwal, Sudhir; Sediqe, Soud A.; Lin, Ming-Fong

    2015-01-01

    Historically, androgen-deprivation therapy has been the cornerstone for treatment of metastatic prostate cancer. Unfortunately, nearly majority patients with prostate cancer transition to the refractory state of castration-resistant prostate cancer (CRPC). Newer therapeutic agents are needed for treating these CRPC patients that are unresponsive to androgen deprivation and/or chemotherapy. The histone deacetylase (HDAC) family of enzymes limits the expression of genomic regions by improving b...

  10. Molecular mechanisms of rosacea pathogenesis

    Directory of Open Access Journals (Sweden)

    Davydova A.M.

    2013-09-01

    Full Text Available The article presents possible molecular mechanisms for rosacea pathogenesis from current domestic and foreign clinical observations and laboratory research: regulation and expression defects of antimicrobial peptides, vascular endothelial growth factor, the effect of serine proteases, oxidative stress, reactive oxygen species and ferritin on the occurrence and course of rosacea. New developments in molecular biology and genetics are advanced for researching the interaction of multiple factors involved in rosacea pathogenesis, as well as providing the bases for potentially new therapies.

  11. [Molecular diagnostics of lung cancer].

    Science.gov (United States)

    Ryska, A; Dziadziuszko, R; Olszewski, W; Berzinec, P; Öz, B; Gottfried, M; Cufer, T; Samarzija, M; Plank, L; Ostoros, Gy; Tímár, J

    2015-09-01

    Development of the target therapies of lung cancer was a rapid process which fundamentally changed the pathological diagnosis as well. Furthermore, molecular pathology became essential part of the routine diagnostics of lung cancer. These changes generated several practical problems and in underdeveloped countries or in those with reimbursement problems have been combined with further challenges. The central and eastern region of Europe are characterized by similar problems in this respect which promoted the foundation of NSCLC Working Group to provide up to date protocols or guidelines. This present paper is a summary of the molecular pathology and target therapy guidelines written with the notion that it has to be upgraded continuously according to the development of the field.

  12. STATINS AND MYOPATHY: MOLECULAR MECHANISMS

    Directory of Open Access Journals (Sweden)

    O. M. Drapkina

    2012-01-01

    Full Text Available The safety of statin therapy is considered. In particular the reasons of a complication such as myopathy are discussed in detail. The molecular mechanisms of statin myopathy , as well as its risk factors are presented. The role of coenzyme Q10 in the myopathy development and coenzyme Q10 application for the prevention of this complication are considered. 

  13. Molecular mechanism of cholangiocarcinoma carcinogenesis.

    Science.gov (United States)

    Maemura, Kosei; Natsugoe, Shoji; Takao, Sonshin

    2014-10-01

    Cholangiocarcinoma (CCA) is a highly malignant cancer of the biliary tract with a poor prognosis, which often arises from conditions causing long-term inflammation, injury, and reparative biliary epithelial cell proliferation. Several conditions are known to be major risk factors for cancer in the biliary tract or gallbladder, including primary sclerosing cholangitis, liver fluke infection, pancreaticobiliary maljunction, and chemical exposure in proof-printing workers. Abnormalities in various signaling cascades, molecules, and genetic mutations are involved in the pathogenesis of CCA. CCA is characterized by a series of highly recurrent mutations in genes, including KRAS, BRF, TP53, Smad, and p16(INK4a) . Cytokines that are affected by inflammatory environmental conditions, such as interleukin-6 (IL-6), transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α), and platelet-derived growth factor (PDGF), play an important role in cancer pathogenesis. Prominent signaling pathways important in carcinogenesis include TGF-β/Smad, IL-6/STAT-3, PI3K/AKT, Wnt, RAF/MEK/MAPK, and Notch. Additionally, some microRNAs regulate targets in critical pathways of CCA development and progression. This review article provides the understanding of the genetic and epigenetic mechanism(s) of carcinogenesis in CCA, which leads to the development of new therapeutic targets for the prevention and treatment of this devastating cancer. PMID:24895231

  14. Molecular Targets and Mechanisms of Cancer Prevention and Treatment by Withaferin A, A Naturally Occurring Steroidal Lactone

    OpenAIRE

    Vyas, Avani R.; Singh, Shivendra V

    2013-01-01

    The plants used in Ayurvedic medicine, which has been practiced in India for thousands of years for the treatment of a variety of disorders, are rich in chemicals potentially useful for prevention and treatment of cancer. Withania somnifera (commonly known as Ashwagandha in Ayurvedic medicine) is one such medicinal plant whose anticancer value was realized over four decades ago after isolation of a crystalline steroidal compound (withaferin A) from the leaves of this shrub. The root and leaf ...

  15. Study of molecular mechanisms of pro-apoptotic activity of NCX 4040, a novel nitric oxide-releasing aspirin, in colon cancer cell lines

    Directory of Open Access Journals (Sweden)

    Vannini Ivan

    2007-10-01

    Full Text Available Abstract Background Despite numerous studies aimed at verifying the antitumor activity of nitric oxide-releasing nonsteroidal antiflammatory drugs (NO-NSAIDs, little is known about the molecular targets responsible for their antineoplastic properties. In the present study, we investigated the mechanisms underlying the cytotoxicity of NCX 4040, a novel NO-aspirin with promising antineoplastic action, in in vitro human colon cancer models. Methods The effect on tumor growth was evaluated in four human colon cancer cell lines (LoVo, LRWZ, WiDr and LoVo Dx by sulforhodamine B assay, oxidative stress by immunohistochemistry, apoptosis by laddering assay, mitochondrial membrane potential (ΔΨm by flow cytometry, and apoptosis- and chemoresistance-related markers by western-blot and real-time method, respectively. Prostaglandin E2 levels were determined by ELISA. Results NCX 4040 produced a higher cytotoxic effect in all the cell lines than that produced by other NO donors tested. In particular, in LoVo and LRWZ cells, NCX 4040 induced a cytocidal effect and apoptosis through p53 and NAG-1 expression, an early ΔΨm collapse, and a sequential release of cytoplasmatic cytochrome c and caspase -9 and -3 active forms. 8-hydroxyguanine lesions, indicative of oxidative stress, were also observed. Conversely, in WiDr line, the drug caused a cytocidal effect, albeit not through apoptosis, and a concomitant increase in COX-2 activity. In LoVo Dx line, characterized by high levels drug resistance and DNA repair-related markers, only a cytostatic effect was observed, again in concomitance with the increase in COX-2 enzyme activity. Conclusion This study highlights the multiplicity of mechanisms involved in sensitivity or resistance to NCX 4040 and could provide useful indications for tailored therapy by identifying potentially drug-responsive tumors.

  16. Molecular Epidemiology of Female Lung Cancer

    OpenAIRE

    Seon-Hee Yim; Yeun-Jun Chung

    2011-01-01

    Lung cancer is still a leading cause of cancer mortality in the world. The incidence of lung cancer in developed countries started to decrease mainly due to global anti-smoking campaigns. However, the incidence of lung cancer in women has been increasing in recent decades for various reasons. Furthermore, since the screening of lung cancer is not as yet very effective, clinically applicable molecular markers for early diagnosis are much required. Lung cancer in women appears to have differenc...

  17. Genetics and molecular biology of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    King, M.C. [California Univ., Berkeley, CA (United States); Lippman, M. [Georgetown Univ. Medical Center, Washington, DC (United States)] [comps.

    1992-12-31

    This volume contains the abstracts of oral presentations and poster sessions presented at the Cold Springs Harbor Meeting on Cancer Cells, this meeting entitled Genetics and Molecular Biology of Breast Cancer.

  18. Effects of miR-424 on Proliferation and Migration Abilities in Non-small Cell Lung Cancer A549 Cells and Its Molecular Mechanism

    Directory of Open Access Journals (Sweden)

    Hongmin LI

    2016-09-01

    Full Text Available Background and objective The inhibitory ability of miR-424 on the proliferation of renal carcinoma cell and the migration and invasion of cancer cells has been widely explored and demonstrated. However, the effects of miR-424 on non-small cell lung cancer (NSCLC have not been systematically examined. In this study, detected the growth and invasion effect of miR-424 in NSCLC A549 cell. The migration and molecular mechanism of this cell are also detected. Methods NSCLC A549 cell was transfected with miR-424 and its inhibitor. After transfection, the proliferation ability of A549 cell was detectedby CCK8 assay. Then, the migration ability in A549 cell was detected by migration assays. Furthermore, the expression level of MMP2 and MMP9 in A549 was detected by Western blot and immune fluorescence. The 3'UTR of E2F6 was cloned into luciferase reporter vector and its enzymatic activitywas detected to verify whether miR-424 can target E2F6. The expression level of E2F6 in a549 cell after transfecing with miR-424 was detected by Western blot. Results After transfection of miR-424, the proliferation and migration abilities were remarkably decreased and the expression level of MMP-2 and MMP-9 were down-regulated in A549. Moreover, MiR-424 inhibited the enzymatic activity of luviferase reporter vector of E2F6. Specifically, the expression level of E2F6 was down-regulated in A549. Conclusion miR-424 can inhibit the proliferation and migration abilities of A549 by negatively regulating the expression of E2F6.

  19. Cellular and Molecular Mechanisms of AKI.

    Science.gov (United States)

    Agarwal, Anupam; Dong, Zheng; Harris, Raymond; Murray, Patrick; Parikh, Samir M; Rosner, Mitchell H; Kellum, John A; Ronco, Claudio

    2016-05-01

    In this article, we review the current evidence for the cellular and molecular mechanisms of AKI, focusing on epithelial cell pathobiology and related cell-cell interactions, using ischemic AKI as a model. Highlighted are the clinical relevance of cellular and molecular targets that have been investigated in experimental models of ischemic AKI and how such models might be improved to optimize translation into successful clinical trials. In particular, development of more context-specific animal models with greater relevance to human AKI is urgently needed. Comorbidities that could alter patient susceptibility to AKI, such as underlying diabetes, aging, obesity, cancer, and CKD, should also be considered in developing these models. Finally, harmonization between academia and industry for more clinically relevant preclinical testing of potential therapeutic targets and better translational clinical trial design is also needed to achieve the goal of developing effective interventions for AKI. PMID:26860342

  20. Fernblock (Polypodium leucotomos Extract: Molecular Mechanisms and Pleiotropic Effects in Light-Related Skin Conditions, Photoaging and Skin Cancers, a Review

    Directory of Open Access Journals (Sweden)

    Concepcion Parrado

    2016-06-01

    Full Text Available Healthier life styles include increased outdoors time practicing sports and walking. This means increased exposure to the sun, leading to higher risk of sunburn, photoaging and skin cancer. In addition to topical barrier products, oral supplementations of various botanicals endowed with antioxidant activity are emerging as novel method of photoprotection. Polypodium leucotomos extract (PL, commercial name Fernblock®, IFC Group, Spain is a powerful antioxidant due to its high content of phenolic compounds. PL is administered orally, with proven safety, and it can also be used topically. Its mechanisms include inhibition of the generation and release of reactive oxygen species (ROS by ultraviolet (UV light. It also prevents UV- and ROS-induced DNA damage with inhibition of AP1 and NF-κB and protection of natural antioxidant enzyme systems. At the cellular level, PL decreases cellular apoptosis and necrosis mediated UV and inhibits abnormal extracellular matrix remodeling. PL reduces inflammation, prevents immunosuppression, activates tumor suppressor p53 and inhibits UV-induced cyclooxygenase-2 (COX-2 enzyme expression. In agreement with increased p53 activity, PL decreased UV radiation-induced cell proliferation. PL also prevents common deletions mitochondrial DNA damage induced by UVA, and MMP-1 expression induced Visible Light and Infrared Radiation. These cellular and molecular effects are reflected in inhibitions of carcinogenesis and photoaging.

  1. Fernblock (Polypodium leucotomos Extract): Molecular Mechanisms and Pleiotropic Effects in Light-Related Skin Conditions, Photoaging and Skin Cancers, a Review

    Science.gov (United States)

    Parrado, Concepcion; Mascaraque, Marta; Gilaberte, Yolanda; Juarranz, Angeles; Gonzalez, Salvador

    2016-01-01

    Healthier life styles include increased outdoors time practicing sports and walking. This means increased exposure to the sun, leading to higher risk of sunburn, photoaging and skin cancer. In addition to topical barrier products, oral supplementations of various botanicals endowed with antioxidant activity are emerging as novel method of photoprotection. Polypodium leucotomos extract (PL, commercial name Fernblock®, IFC Group, Spain) is a powerful antioxidant due to its high content of phenolic compounds. PL is administered orally, with proven safety, and it can also be used topically. Its mechanisms include inhibition of the generation and release of reactive oxygen species (ROS) by ultraviolet (UV) light. It also prevents UV- and ROS-induced DNA damage with inhibition of AP1 and NF-κB and protection of natural antioxidant enzyme systems. At the cellular level, PL decreases cellular apoptosis and necrosis mediated UV and inhibits abnormal extracellular matrix remodeling. PL reduces inflammation, prevents immunosuppression, activates tumor suppressor p53 and inhibits UV-induced cyclooxygenase-2 (COX-2) enzyme expression. In agreement with increased p53 activity, PL decreased UV radiation-induced cell proliferation. PL also prevents common deletions mitochondrial DNA damage induced by UVA, and MMP-1 expression induced Visible Light and Infrared Radiation. These cellular and molecular effects are reflected in inhibitions of carcinogenesis and photoaging. PMID:27367679

  2. Circadian molecular clocks and cancer.

    Science.gov (United States)

    Kelleher, Fergal C; Rao, Aparna; Maguire, Anne

    2014-01-01

    Physiological processes such as the sleep-wake cycle, metabolism and hormone secretion are controlled by a circadian rhythm adapted to 24h day-night periodicity. This circadian synchronisation is in part controlled by ambient light decreasing melatonin secretion by the pineal gland and co-ordinated by the suprachiasmatic nucleus of the hypothalamus. Peripheral cell autonomous circadian clocks controlled by the suprachiasmatic nucleus, the master regulator, exist within every cell of the body and are comprised of at least twelve genes. These include the basic helix-loop-helix/PAS domain containing transcription factors; Clock, BMal1 and Npas2 which activate transcription of the periodic genes (Per1 and Per2) and cryptochrome genes (Cry1 and Cry2). Points of coupling exist between the cellular clock and the cell cycle. Cell cycle genes which are affected by the molecular circadian clock include c-Myc, Wee1, cyclin D and p21. Therefore the rhythm of the circadian clock and cancer are interlinked. Molecular examples exist including activation of Per2 leads to c-myc overexpression and an increased tumor incidence. Mice with mutations in Cryptochrome 1 and 2 are arrhythmic (lack a circadian rhythm) and arrhythmic mice have a faster rate of growth of implanted tumors. Epidemiological finding of relevance include 'The Nurses' Health Study' where it was established that women working rotational night shifts have an increased incidence of breast cancer. Compounds that affect circadian rhythm exist with attendant future therapeutic possibilities. These include casein kinase I inhibitors and a candidate small molecule KL001 that affects the degradation of cryptochrome. Theoretically the cell cycle and malignant disease may be targeted vicariously by selective alteration of the cellular molecular clock. PMID:24099911

  3. Development of New Molecular EZH2 on Lung Cancer Invasion and Metastasis

    Directory of Open Access Journals (Sweden)

    Hui XIA

    2016-02-01

    Full Text Available Lung cancer is a serious threat to human health malignancies upward trend in morbidity and mortality. It is hot topic to investigate the molecular mechanisms of lung cancer development and explore the new therapeutic targets. The underlying mechanism of EZH2 on lung cancer development will demonstrate the new pathway of lung cancer development, invasion and metastasis. The exploration and application of new targeted molecular will improve the survival rate and living quality of lung cancer patients in future.

  4. [Molecular bases of cancer immunology].

    Science.gov (United States)

    Barrera-Rodríguez, R; Peralta-Zaragoza, O; Madrid-Marina, V

    1995-01-01

    The immune system is a tight network of different types of cells and molecules. The coordinated action of these elements mounts a precise immune response against tumor cells. However, these cells present several escape mechanisms, leading to tumor progression. This paper shows several cellular and molecular events involved in the regulation of the immune response against tumor cells. The interaction of several molecules such as MHC, TcR, adhesins, tumor antigens and cytokines are discussed, as well as the most recent knowledge about escape mechanisms and immunotherapy. PMID:7502157

  5. Molecular imaging of apoptosis in cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hakumaeki, Juhana M. [Cellular and Molecular Imaging Group, Department of Biomedical NMR, A.I. Virtanen Institute for Molecular Sciences, University of Kuopio, P.O. Box 1627, FI-70211 Kuopio (Finland) and Department of Clinical Radiology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland)]. E-mail: juhana.hakumaki@uku.fi; Liimatainen, Timo [Cellular and Molecular Imaging Group, Department of Biomedical NMR, A.I. Virtanen Institute for Molecular Sciences, University of Kuopio, P.O. Box 1627, FI-70211 Kuopio (Finland)

    2005-11-01

    Apoptosis plays an important role in cancer. Mechanisms hindering its action are implicated in a number of malignancies. Also, the induction of apoptosis plays a pivotal role in non-surgical cancer treatment regimes such as irradiation, chemotherapy, or hormones. Recent advanced in imaging science have made it now possible for us to detect and visualize previously inaccessible and even unrecognized biological phenomena in cells and tissue undergoing apoptosis in vivo. Not only are these imaging techniques painting an intriguing picture of the spatiotemporal characteristics and metabolic and biophysical of apoptosis in situ, but they are expected to have an ever increasing impact in preclinical testing and design of new anticancer agents as well. Rapid and accurate visualization of apoptotic response in the clinical settings can also be of significant diagnostic and prognostic worth. With the advent of molecular medicine and patient-tailored treatment options and therapeutic agents, such monitoring techniques are becoming paramount.

  6. Epigenetic mechanisms in gastric cancer.

    Science.gov (United States)

    Gigek, Carolina Oliveira; Chen, Elizabeth Suchi; Calcagno, Danielle Queiroz; Wisnieski, Fernanda; Burbano, Rommel Rodriguez; Smith, Marilia Arruda Cardoso

    2012-06-01

    Cancer is considered one of the major health issues worldwide, and gastric cancer accounted for 8% of total cases and 10% of total deaths in 2008. Gastric cancer is considered an age-related disease, and the total number of newly diagnosed cases has been increasing as a result of the higher life expectancy. Therefore, the basic mechanisms underlying gastric tumorigenesis is worth investigation. This review provides an overview of the epigenetic mechanisms, such as DNA methylation, histone modifications, chromatin remodeling complex and miRNA, involved in gastric cancer. As the studies in gastric cancer continue, the mapping of an epigenome code is not far for this disease. In conclusion, an epigenetic therapy might appear in the not too distant future.

  7. Molecular Diagnostic Applications in Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Laura Huth

    2014-06-01

    Full Text Available Colorectal cancer, a clinically diverse disease, is a leading cause of cancer-related death worldwide. Application of novel molecular diagnostic tests, which are summarized in this article, may lead to an improved survival of colorectal cancer patients.  Distinction of these applications is based on the different molecular principles found in colorectal cancer (CRC. Strategies for molecular analysis of single genes (as KRAS or TP53 as well as microarray based techniques are discussed. Moreover, in addition to the fecal occult blood testing (FOBT and colonoscopy some novel assays offer approaches for early detection of colorectal cancer like the multitarget stool DNA test or the blood-based Septin 9 DNA methylation test. Liquid biopsy analysis may also exhibit great diagnostic potential in CRC for monitoring developing resistance to treatment. These new diagnostic tools and the definition of molecular biomarkers in CRC will improve early detection and targeted therapy of colorectal cancer.

  8. Hyperinsulinaemic Hypoglycaemia - The Molecular Mechanisms

    Directory of Open Access Journals (Sweden)

    Azizun eNessa

    2016-03-01

    Full Text Available Under normal physiological conditions pancreatic β-cells secrete insulin to maintain fasting blood glucose levels in the range 3.5-5.5mmol/L. In hyperinsulinaemic hypoglycaemia (HH this precise regulation of insulin secretion is perturbed so that insulin continues to be secreted in the presence of hypoglycaemia. HH may be due to genetic causes (congenital or secondary to certain risk factors. The molecular mechanisms leading to HH involve defects in the key genes regulating insulin secretion from the β-cells. At this moment in time genetic abnormalities in 9 genes (ABCC8, KCNJ11, GCK, SCHAD, GLUD1, SLC16A1, HNF1A, HNF4A and UCP2 have been described that lead to the congenital forms of HH. Perinatal stress, intrauterine growth retardation, maternal diabetes mellitus and a large number of developmental syndromes are also associated with HH in the neonatal period. In older children and adult’s insulinoma, Noninsulinoma pancreatogenous hypoglycaemia syndrome and post bariatric surgery are recognised causes of HH. This review article will focus mainly on describing the molecular mechanisms that lead to unregulated insulin secretion.

  9. Molecular biological mechanism II. Molecular mechanisms of cell cycle regulation

    International Nuclear Information System (INIS)

    The cell cycle in eukaryotes is regulated by central cell cycle controlling protein kinase complexes. These protein kinase complexes consist of a catalytic subunit from the cyclin-dependent protein kinase family (CDK), and a regulatory subunit from the cyclin family. Cyclins are characterised by their periodic cell cycle related synthesis and destruction. Each cell cycle phase is characterised by a specific set of CDKs and cyclins. The activity of CDK/cyclin complexes is mainly regulated on four levels. It is controlled by specific phosphorylation steps, the synthesis and destruction of cyclins, the binding of specific inhibitor proteins, and by active control of their intracellular localisation. At several critical points within the cell cycle, named checkpoints, the integrity of the cellular genome is monitored. If damage to the genome or an unfinished prior cell cycle phase is detected, the cell cycle progression is stopped. These cell cycle blocks are of great importance to secure survival of cells. Their primary importance is to prevent the manifestation and heritable passage of a mutated genome to daughter cells. Damage sensing, DNA repair, cell cycle control and apoptosis are closely linked cellular defence mechanisms to secure genome integrity. Disregulation in one of these defence mechanisms are potentially correlated with an increased cancer risk and therefore in at least some cases with an increased radiation sensitivity. (orig.)

  10. Molecular Mechanism of Somite Development

    Directory of Open Access Journals (Sweden)

    Gulfidan Coskun

    2013-06-01

    Full Text Available From third week of gestation, notochord and the neural folds begin to gather at the center of the embryo to form the paraxial mesoderm. Paraxial mesoderm separates into blocks of cells called somitomers at the lateral sides of the neural tube of the head region. At the beginning of the third week somitomeres take ring shapes and form blocks of somites from occipital region to caudal region. Although somites are transient structures, they are extremely important in organizing the segmental pattern of vertebrate embryos. Somites give rise to the cells that form the vertebrae and ribs, the dermis of the dorsal skin, the skeletal muscles of the back, and the skeletal muscles of the body wall and limbs. Somitogenesis are formed by a genetic mechanism that is regulated by cyclical expression of genes in the Notch, Wnt and fibroblast growth factor signaling pathways. The prevailing model of the mechanism governing somitogenesis is the “clock and wave front”. Somitogenesis has components of periodicity, separation, epithelialization and axial specification. According to this model, the clock causes cells to undergo repeated oscillations, with a particular phase of each oscillation defining the competency of cells in the presomitic mesoderm to form a somite. Any disruption in this mechanism can be cause of severe segmentation defects of the vertebrae and congenital anomalies. In this review, we discuss the molecular mechanisms underlying the somitogenesis which is an important part of morphogenesis. [Archives Medical Review Journal 2013; 22(3.000: 362-376

  11. Molecular Mechanisms Underlying Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Christian Trepo

    2009-11-01

    Full Text Available Hepatocarcinogenesis is a complex process that remains still partly understood. That might be explained by the multiplicity of etiologic factors, the genetic/epigenetic heterogeneity of tumors bulks and the ignorance of the liver cell types that give rise to tumorigenic cells that have stem cell-like properties. The DNA stress induced by hepatocyte turnover, inflammation and maybe early oncogenic pathway activation and sometimes viral factors, leads to DNA damage response which activates the key tumor suppressive checkpoints p53/p21Cip1 and p16INK4a/pRb responsible of cell cycle arrest and cellular senescence as reflected by the cirrhosis stage. Still obscure mechanisms, but maybe involving the Wnt signaling and Twist proteins, would allow pre-senescent hepatocytes to bypass senescence, acquire immortality by telomerase reactivation and get the last genetic/epigenetic hits necessary for cancerous transformation. Among some of the oncogenic pathways that might play key driving roles in hepatocarcinogenesis, c-myc and the Wnt/β-catenin signaling seem of particular interest. Finally, antiproliferative and apoptosis deficiencies involving TGF-β, Akt/PTEN, IGF2 pathways for instance are prerequisite for cancerous transformation. Of evidence, not only the transformed liver cell per se but the facilitating microenvironment is of fundamental importance for tumor bulk growth and metastasis.

  12. Molecular Mechanisms of Cardiovascular Aging

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2013-12-01

    Full Text Available BACKGROUND: The average lifespan of humans is increasing, and with it the percentage of people entering the 65 and older age group is growing rapidly and will continue to do so in the next 20 years. Within this age group, cardiovascular disease will remain the leading cause of death, and the cost associated with treatment will continue to increase. Aging is an inevitable part of life and unfortunately poses the largest risk factor for cardiovascular disease. CONTENT: We provide an overview of some of the molecular mechanisms involved in regulating lifespan and health, including mitochondria, telomeres, stem cells, sirtuins, Adenosine Monophosphate-activated Protein Kinase, Mammalian Target of Rapamycin and Insulin-like Growth Factor 1. We also provide future perspectives of lifespan and health, which are intimately linked fields. SUMMARY: Aging remains the biggest non-modifiable risk factor for cardiovascular disease. The biological, structural and mechanical changes in senescent cardiovascular system are thought to contribute in increasing incidence of cardiovascular disease in aging. Understanding the mechanisms contributing to such changes is therefore crucial for both prevention and development of treatment for cardiovascular diseases. KEYWORDS: cardiovascular aging, mitochondria, telomeres, sirtuin, stem cells.

  13. Molecular Mechanisms Behind the Chemopreventive Effects of Anthocyanidins

    Directory of Open Access Journals (Sweden)

    De-Xing Hou

    2004-01-01

    Full Text Available Anthocyanins are polyphenolic ring-based flavonoids, and are widespread in fruits and vegetables of red-blue color. Epidemiological investigations and animal experiments have indicated that anthocyanins may contribute to cancer chemoprevention. The studies on the mechanism have been done recently at molecular level. This review summarizes current molecular bases for anthocyanidins on several key steps involved in cancer chemoprevention: (i inhibition of anthocyanidins in cell transformation through targeting mitogen-activated protein kinase (MAPK pathway and activator protein 1 (AP-1 factor; (ii suppression of anthocyanidins in inflammation and carcinogenesis through targeting nuclear factor kappa B (NF-κB pathway and cyclooxygenase 2 (COX-2 gene; (iii apoptotic induction of cancer cells by anthocyanidins through reactive oxygen species (ROS / c-Jun NH2-terminal kinase (JNK-mediated caspase activation. These data provide a first molecular view of anthocyanidins contributing to cancer chemoprevention.

  14. Molecular Mechanisms of Bacterial Pathogenicity

    Science.gov (United States)

    Fuchs, Thilo Martin

    Cautious optimism has arisen over recent decades with respect to the long struggle against bacteria, viruses, and parasites. This has been offset, however, by a fatal complacency stemming from previous successes such as the development of antimicrobial drugs, the eradication of smallpox, and global immunization programs. Infectious diseases nevertheless remain the world's leading cause of death, killing at least 17 million persons annually [61]. Diarrheal diseases caused by Vibrio cholerae or Shigella dysenteriae kill about 3 million persons every year, most of them young children: Another 4 million die of tuberculosis or tetanus. Outbreaks of diphtheria in Eastern Europe threatens the population with a disease that had previously seemed to be overcome. Efforts to control infectious diseases more comprehensively are undermined not only by socioeconomic conditions but also by the nature of the pathogenic organisms itself; some isolates of Staphylococcus aureus and Enterobacter have become so resistant to drugs by horizontal gene transfer that they are almost untreatable. In addition, the mechanism of genetic variability helps pathogens to evade the human immune system, thus compromising the development of powerful vaccines. Therefore detailed knowledge of the molecular mechanisms of microbial pathogenicity is absolutely necessary to develop new strategies against infectious diseases and thus to lower their impact on human health and social development.

  15. Molecular Biology of Esophageal Cancer

    Institute of Scientific and Technical Information of China (English)

    HuanXi; JanBrabender; RalfMetzger; PaulM.Schneider

    2004-01-01

    There have been many new developments in our understanding of esophageal carcinoma biology over the past several years. Information regarding both of the major forms of this disease, adenocarcinoma and squamous cell carcinoma, has accumulated in conjunction with data on precursor conditions such as Barrett's esophagus. Interesting and promising findings have included overexpression of proto-oncogenes,loss of heterozygosity at multiple chromosomal loci, tumor suppressor gene inactivation, epigenetic silencing by DNA methylation, and mutations and deletions involving the tumor suppressor gene p53. Important cancer pathways, the cyclin kinase inhibitor cascade and the DNA mismatch repair process, implicated in the genesis of multiple tumor types have also been inculpated in esophageal carcinogenesis. Alterations in the p16 and p15 cyclin kinase inhibitors including point mutations and homozygous deletions have been reported in primary esophageal tumors. Further developments in the field of molecular carcinogenesis of esophageal malignancies promise to yield improvements in prevention, early detection, prognostic categorization, and perhaps gene-based therapy of this deadly disease.

  16. Integrated Molecular Profiling in Advanced Cancers Trial

    Science.gov (United States)

    2016-06-21

    Breast Cancer; Non-small Cell Lung Cancer; Colorectal Cancer; Genitourinary Cancer; Pancreatobiliary Gastrointestinal Cancer; Upper Aerodigestive Tract Cancer; Gynecological Cancers; Melanoma Cancers; Rare Cancers; Unknown Primary Cancers

  17. Molecular mechanisms in radiation carcinogenesis: introduction

    International Nuclear Information System (INIS)

    Molecular studies of radiation carcinogenesis are discussed in relation to theories for extrapolating from cellular and animal models to man. Skin cancer is emphasized because of sunlight-induced photochemical damage to DNA. It is emphasized that cellular and animal models are needed as well as molecular theories for quantitative evaluation of hazardous environmental agents. (U.S.)

  18. Molecular imaging of prostate cancer with PET.

    Science.gov (United States)

    Jadvar, Hossein

    2013-10-01

    Molecular imaging is paving the way for precision and personalized medicine. In view of the significant biologic and clinical heterogeneity of prostate cancer, molecular imaging is expected to play an important role in the evaluation of this prevalent disease. The natural history of prostate cancer spans from an indolent localized process to biochemical relapse after radical treatment with curative intent to a lethal castrate-resistant metastatic disease. The ongoing unraveling of the complex tumor biology of prostate cancer uniquely positions molecular imaging with PET to contribute significantly to every clinical phase of prostate cancer evaluation. The purpose of this article was to provide a concise review of the current state of affairs and potential future developments in the diagnostic utility of PET in prostate cancer.

  19. Genetic and molecular changes in ovarian cancer

    Science.gov (United States)

    Hollis, Robert L; Gourley, Charlie

    2016-01-01

    Epithelial ovarian cancer represents the most lethal gynecological malignancy in the developed world, and can be divided into five main histological subtypes: high grade serous, endometrioid, clear cell, mucinous and low grade serous. These subtypes represent distinct disease entities, both clinically and at the molecular level. Molecular analysis has revealed significant genetic heterogeneity in ovarian cancer, particularly within the high grade serous subtype. As such, this subtype has been the focus of much research effort to date, revealing molecular subgroups at both the genomic and transcriptomic level that have clinical implications. However, stratification of ovarian cancer patients based on the underlying biology of their disease remains in its infancy. Here, we summarize the molecular changes that characterize the five main ovarian cancer subtypes, highlight potential opportunities for targeted therapeutic intervention and outline priorities for future research.

  20. Molecular Profiling of Prostate Cancer Patients

    OpenAIRE

    Nna, Emmanuel Okechukwu

    2009-01-01

    In the UK, more than 30 000 men are diagnosed annually with prostate cancer (PCa) and about 10 000 men die from it each year. Although several molecular markers have been associated with prostate cancer development and/ or progression, only few of them are used in diagnostic pathology. The current standard tests include serum PSA test, digital rectal examination and histology of prostate biopsy. Recently the PCA-3 molecular test was approved in the European Union, and it is now...

  1. Molecular imaging of breast cancer

    NARCIS (Netherlands)

    Adams, A.L.L.

    2014-01-01

    Breast cancer is the most common type of cancer in women. Imaging techniques play a pivotal role in breast cancer management, especially in lesion detection, treatment planning and evaluation, and prognostication. These imaging techniques have however limitations such as the use of ionizing radiatio

  2. Pomegranate Extracts and Cancer Prevention: Molecular and Cellular Activities

    OpenAIRE

    Syed, Deeba N.; Chamcheu, Jean-Christopher; Adhami, Vaqar M.; Mukhtar, Hasan

    2013-01-01

    There is increased appreciation by the scientific community that dietary phytochemicals can be potential weapons in the fight against cancer. Emerging data has provided new insights into the molecular and cellular framework needed to establish novel mechanism-based strategies for cancer prevention by selective bioactive food components. The unique chemical composition of the pomegranate fruit, rich in antioxidant tannins and flavonoids has drawn the attention of many investigators. Polyphenol...

  3. Experimental therapy of ovarian cancer with synthetic makaluvamine analog: in vitro and in vivo anticancer activity and molecular mechanisms of action.

    Directory of Open Access Journals (Sweden)

    Tao Chen

    Full Text Available The present study was designed to determine the biological effects of novel marine alkaloid analog 7-(4-fluorobenzylamino-1,3,4,8-tetrahydropyrrolo[4,3,2-de]quinolin-8(1H-one (FBA-TPQ on human ovarian cancer cells for its anti-tumor potential and the underlying mechanisms as a novel chemotherapeutic agent. Human ovarian cancer cells (A2780 and OVCAR-3, and Immortalized non-tumorigenic human Ovarian Surface Epithelial cells (IOSE-144, were exposed to FBA-TPQ for initial cytotoxicity evaluation (via MTS assay kit, Promega. The detailed in-vitro (cell level and in-vivo (animal model studies on the antitumor effects and possible underlying mechanisms of action of the compounds were then performed. FBA-TPQ exerted potent cytotoxicity against human ovarian cancer A2780 and OVCAR-3 cells as an effective inhibitor of cell growth and proliferation, while exerting lesser effects on non-tumorigenic IOSE-144 cells. Further study in the more sensitive OVCAR-3 cell line showed that it could potently induce cell apoptosis (Annexin V-FITC assay, G2/M cell cycle arrest (PI staining analysis and also dose-dependently inhibit OVCAR-3 xenograft tumors' growth on female athymic nude mice (BALB/c, nu/nu. Mechanistic studies (both in vitro and in vivo revealed that FBA-TPQ might exert its activity through Reactive Oxygen Species (ROS-associated activation of the death receptor, p53-MDM2, and PI3K-Akt pathways in OVCAR-3 cells, which is in accordance with in vitro microarray (Human genome microarrays, Agilent data analysis (GEO accession number: GSE25317. In conclusion, FBA-TPQ exhibits significant anticancer activity against ovarian cancer cells, with minimal toxicity to non-tumorigenic human IOSE-144 cells, indicating that it may be a potential therapeutic agent for ovarian cancer.

  4. Molecular biology of the lung cancer

    International Nuclear Information System (INIS)

    Background. Lung cancer is one of the most common malignant diseases and leading cause of cancer death worldwide. The advances in molecular biology and genetics, including the modern microarray technology and rapid sequencing techniques, have enabled a remarkable progress into elucidating the lung cancer ethiopathogenesis. Numerous studies suggest that more than 20 different genetic and epigenetic alterations are accumulating during the pathogenesis of clinically evident pulmonary cancers as a clonal, multistep process. Thus far, the most investigated alterations are the inactivational mutations and losses of tumour suppressor genes and the overexpression of growth-promoting oncogenes. More recently, the acquired epigenetic inactivation of tumour suppressor genes by promoter hypermethylation has been recognized. The early clonal genetic abnormalities that occur in preneoplastic bronchial epithelium damaged by smoking or other carcinogenes are being identified. The molecular distinctions between small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), as well as between tumors with different clinical outcomes have been described. These investigations lead to the hallmarks of lung cancer. Conclusions. It is realistic to expect that the molecular and cell culture-based investigations will lead to discoveries of new clinical applications with the potential to provide new avenues for early diagnosis, risk assessment, prevention, and most important, new more effective treatment approaches for the lung cancer patients. (author)

  5. Radionuclide molecular target therapy for lung cancer

    International Nuclear Information System (INIS)

    Lung cancer harms people's health or even lives severely. Currently, the morbidity and mortality of lung cancer are ascending all over the world. Accounting for 38.08% of malignant tumor caused death in male and 16% in female in cities,ranking top in both sex. Especially, the therapy of non-small cell lung cancer has not been obviously improved for many years. Recently, sodium/iodide transporter gene transfection and the therapy of molecular target drugs mediated radionuclide are being taken into account and become the new research directions in treatment of advanced lung cancer patients with the development of technology and theory for medical molecular biology and the new knowledge of lung cancer's pathogenesis. (authors)

  6. Exploiting novel molecular targets in gastrointestinal cancers

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Novel molecular targets are being discovered as we learn more about the aberrant processes underlying various cancers. Efforts to translate this knowledge are starting to impact on the care of patients with gastrointestinal cancers. The epidermal growth factor receptor (EGFR) pathway and angiogenesis have been targeted successfully in colorectal cancer with cetuximab, panitunumab and bevacizumab. Similarly, EGFR-targeting with erlotinib yielded significant survival benefit in pancreatic cancer when combined with gemcitabine. The multi-targeting approach with sorafenib has made it the first agent to achieve significant survival benefit in hepatocellular carcinoma. Efforts to exploit the dysregulated Akt/mTOR pathway in GI cancer therapy are ongoing. These molecular targets can be disrupted by various approaches, including the use of monoclonal antibody to intercept extracellular ligands and disrupt receptor-ligand binding, and small molecule inhibitors that interrupt the activation of intracellular kinases.

  7. DNA aptamers as molecular probes for colorectal cancer study.

    Directory of Open Access Journals (Sweden)

    Kwame Sefah

    Full Text Available BACKGROUND: Understanding the molecular features of specific tumors can increase our knowledge about the mechanism(s underlying disease development and progression. This is particularly significant for colorectal cancer, which is a heterogeneous complex of diseases developed in a sequential manner through a multistep carcinogenic process. As such, it is likely that tumors with similar characteristics might originate in the same manner and have a similar molecular behavior. Therefore, specific mapping of the molecular features can be potentially useful for both tumor classification and the development of appropriate therapeutic regimens. However, this can only be accomplished by developing high-affinity molecular probes with the ability to recognize specific markers associated with different tumors. Aptamers can most easily meet this challenge based on their target diversity, flexible manipulation and ease of development. METHODOLOGY AND RESULTS: Using a method known as cell-based Systematic Evolution of Ligands by Exponential enrichment (cell-SELEX and colorectal cancer cultured cell lines DLD-1 and HCT 116, we selected a panel of target-specific aptamers. Binding studies by flow cytometry and confocal microscopy showed that these aptamers have high affinity and selectivity. Our data further show that these aptamers neither recognize normal colon cells (cultured and fresh, nor do they recognize most other cancer cell lines tested. CONCLUSION/SIGNIFICANCE: The selected aptamers can identify specific biomarkers associated with colorectal cancers. We believe that these probes could be further developed for early disease detection, as well as prognostic markers, of colorectal cancers.

  8. Molecular mechanism of cisplatin resistance

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Cisplatin is widely used in the treatment of many tumors,particularly in ovarian cancer.GST-π,metallothionein(MT), multidrug resistance associated proteins(MRPs), nucleotide excision repair(NER), mismatch repair(MMR) and oncogenes contribute to drug resistance of cisplatin.

  9. Insights into cancer severity from biomolecular interaction mechanisms

    Science.gov (United States)

    Raimondi, Francesco; Singh, Gurdeep; Betts, Matthew J.; Apic, Gordana; Vukotic, Ranka; Andreone, Pietro; Stein, Lincoln; Russell, Robert B.

    2016-01-01

    To attain a deeper understanding of diseases like cancer, it is critical to couple genetics with biomolecular mechanisms. High-throughput sequencing has identified thousands of somatic mutations across dozens of cancers, and there is a pressing need to identify the few that are pathologically relevant. Here we use protein structure and interaction data to interrogate nonsynonymous somatic cancer mutations, identifying a set of 213 molecular interfaces (protein-protein, -small molecule or –nucleic acid) most often perturbed in cancer, highlighting several potentially novel cancer genes. Over half of these interfaces involve protein-small-molecule interactions highlighting their overall importance in cancer. We found distinct differences in the predominance of perturbed interfaces between cancers and histological subtypes and presence or absence of certain interfaces appears to correlate with cancer severity. PMID:27698488

  10. Cancer Hallmarks, Biomarkers and Breast Cancer Molecular Subtypes.

    Science.gov (United States)

    Dai, Xiaofeng; Xiang, Liangjian; Li, Ting; Bai, Zhonghu

    2016-01-01

    Breast cancer is a complex disease encompassing multiple tumor entities, each characterized by distinct morphology, behavior and clinical implications. Besides estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2, novel biomarkers have shown their prognostic and predictive values, complicating our understanding towards to the heterogeneity of such cancers. Ten cancer hallmarks have been proposed by Weinberg to characterize cancer and its carcinogenesis. By reviewing biomarkers and breast cancer molecular subtypes, we propose that the divergent outcome observed from patients stratified by hormone status are driven by different cancer hallmarks. 'Sustaining proliferative signaling' further differentiates cancers with positive hormone receptors. 'Activating invasion and metastasis' and 'evading immune destruction' drive the differentiation of triple negative breast cancers. 'Resisting cell death', 'genome instability and mutation' and 'deregulating cellular energetics' refine breast cancer classification with their predictive values. 'Evading growth suppressors', 'enabling replicative immortality', 'inducing angiogenesis' and 'tumor-promoting inflammation' have not been involved in breast cancer classification which need more focus in the future biomarker-related research. This review novels in its global view on breast cancer heterogeneity, which clarifies many confusions in this field and contributes to precision medicine. PMID:27390604

  11. Molecular deformation mechanisms in polyethylene

    CERN Document Server

    Coutry, S

    2001-01-01

    adjacent labelled stems is significantly larger when the DPE guest is a copolymer molecule. Our comparative studies on various types of polyethylene lead to the conclusion that their deformation behaviour under drawing has the same basis, with additional effects imputed to the presence of tie-molecules and branches. Three major points were identified in this thesis. The changes produced by drawing imply (1) the crystallisation of some of the amorphous polymer and the subsequent orientation of the newly formed crystals, (2) the re-orientation of the crystalline ribbons and (3) the beginning of crystallite break-up. However, additional effects were observed for the high molecular weight linear sample and the copolymer sample and were attributed, respectively, to the presence of tie-molecules and of branches. It was concluded that both the tie-molecules and the branches are restricting the molecular movement during deformation, and that the branches may be acting as 'anchors'. This work is concerned with details...

  12. Harmful molecular mechanisms in sepsis

    OpenAIRE

    Rittirsch, Daniel; Flierl, Michael A; Ward, Peter A.

    2008-01-01

    Sepsis and sepsis-associated multi-organ failure are major challenges for scientists and clinicians and are a tremendous burden for health-care systems. Despite extensive basic research and clinical studies, the pathophysiology of sepsis is still poorly understood. We are now beginning to understand that sepsis is a heterogeneous, dynamic syndrome caused by imbalances in the ‘inflammatory network’. In this Review, we highlight recent insights into the molecular interactions that occur during ...

  13. Bladder cancer: molecular determinants of personalized therapy.

    Science.gov (United States)

    Lopez-Beltran, Antonio; Santoni, Matteo; Massari, Francesco; Ciccarese, Chiara; Tortora, Giampaolo; Cheng, Liang; Moch, Holger; Scarpelli, Marina; Reymundo, Carlos; Montironi, Rodolfo

    2015-01-01

    Several molecular and genetic studies have provided new perspectives on the histologic classification of bladder tumors. Recent developments in the field of molecular mutational pathway analyses based on next generation sequencing technology together with classic data derived from the description of mutations in the FGFR3 (fibroblast growth factor receptor 3) gene, mutations on TP53 gene, and cDNA technology profiling data gives support to a differentiated taxonomy of bladder cancer. All these changes are behind the use of non-traditional approach to therapy of bladder cancer patients and are ready to change our daily practice of uro-oncology. The observed correlation of some molecular alterations with tumor behavior and the identification of their targets at cellular level might support the use of molecular changes together with morphological data to develop new clinical and biological strategies to manage patients with urothelial cancer. The current review provides comprehensive data to support personalized therapy for bladder cancer based on an integrated approach including pathologic and clinical features and molecular biology.

  14. Molecular markers for prostate cancer.

    NARCIS (Netherlands)

    Reynolds, M.A.; Kastury, K.; Groskopf, J.; Schalken, J.A.; Rittenhouse, H.G.

    2007-01-01

    Serum PSA testing has been used for over 20 years as an aid in the diagnosis and management of prostate cancer. Although highly sensitive, it suffers from a lack of specificity, showing elevated serum levels in a variety of other conditions including prostatitis, benign prostate hyperplasia, and non

  15. Resveratrol and calcium signaling: molecular mechanisms and clinical relevance.

    Science.gov (United States)

    McCalley, Audrey E; Kaja, Simon; Payne, Andrew J; Koulen, Peter

    2014-06-05

    Resveratrol is a naturally occurring compound contributing to cellular defense mechanisms in plants. Its use as a nutritional component and/or supplement in a number of diseases, disorders, and syndromes such as chronic diseases of the central nervous system, cancer, inflammatory diseases, diabetes, and cardiovascular diseases has prompted great interest in the underlying molecular mechanisms of action. The present review focuses on resveratrol, specifically its isomer trans-resveratrol, and its effects on intracellular calcium signaling mechanisms. As resveratrol's mechanisms of action are likely pleiotropic, its effects and interactions with key signaling proteins controlling cellular calcium homeostasis are reviewed and discussed. The clinical relevance of resveratrol's actions on excitable cells, transformed or cancer cells, immune cells and retinal pigment epithelial cells are contrasted with a review of the molecular mechanisms affecting calcium signaling proteins on the plasma membrane, cytoplasm, endoplasmic reticulum, and mitochondria. The present review emphasizes the correlation between molecular mechanisms of action that have recently been identified for resveratrol and their clinical implications.

  16. Resveratrol and Calcium Signaling: Molecular Mechanisms and Clinical Relevance

    Directory of Open Access Journals (Sweden)

    Audrey E. McCalley

    2014-06-01

    Full Text Available Resveratrol is a naturally occurring compound contributing to cellular defense mechanisms in plants. Its use as a nutritional component and/or supplement in a number of diseases, disorders, and syndromes such as chronic diseases of the central nervous system, cancer, inflammatory diseases, diabetes, and cardiovascular diseases has prompted great interest in the underlying molecular mechanisms of action. The present review focuses on resveratrol, specifically its isomer trans-resveratrol, and its effects on intracellular calcium signaling mechanisms. As resveratrol’s mechanisms of action are likely pleiotropic, its effects and interactions with key signaling proteins controlling cellular calcium homeostasis are reviewed and discussed. The clinical relevance of resveratrol’s actions on excitable cells, transformed or cancer cells, immune cells and retinal pigment epithelial cells are contrasted with a review of the molecular mechanisms affecting calcium signaling proteins on the plasma membrane, cytoplasm, endoplasmic reticulum, and mitochondria. The present review emphasizes the correlation between molecular mechanisms of action that have recently been identified for resveratrol and their clinical implications.

  17. Molecular mechanism of insulin resistance

    Indian Academy of Sciences (India)

    Samir Bhattacharya; Debleena Dey; Sib Sankar Roy

    2007-03-01

    Free fatty acids are known to play a key role in promoting loss of insulin sensitivity, thereby causing insulin resistance and type 2 diabetes. However, the underlying mechanism involved is still unclear. In searching for the cause of the mechanism, it has been found that palmitate inhibits insulin receptor (IR) gene expression, leading to a reduced amount of IR protein in insulin target cells. PDK1-independent phosphorylation of PKCε causes this reduction in insulin receptor gene expression. One of the pathways through which fatty acid can induce insulin resistance in insulin target cells is suggested by these studies. We provide an overview of this important area, emphasizing the current status.

  18. Cancer cachexia, mechanism and treatment

    Institute of Scientific and Technical Information of China (English)

    Tomoyoshi Aoyagi; Krista P Terracina; Ali Raza; Hisahiro Matsubara; Kazuaki Takabe

    2015-01-01

    It is estimated that half of all patients with cancereventually develop a syndrome of cachexia, with anorexiaand a progressive loss of adipose tissue and skeletalmuscle mass. Cancer cachexia is characterized by systemicinflammation, negative protein and energy balance, andan involuntary loss of lean body mass. It is an insidioussyndrome that not only has a dramatic impact on patientquality of life, but also is associated with poor responsesto chemotherapy and decreased survival. Cachexia isstill largely an underestimated and untreated condition,despite the fact that multiple mechanisms are reported tobe involved in its development, with a number of cytokinespostulated to play a role in the etiology of the persistentcatabolic state. Existing therapies for cachexia, includingorexigenic appetite stimulants, focus on palliation ofsymptoms and reduction of the distress of patients andfamilies rather than prolongation of life. Recent therapiesfor the cachectic syndrome involve a multidisciplinaryapproach. Combination therapy with diet modificationand/or exercise has been added to novel pharmaceuticalagents, such as Megestrol acetate, medroxyprogesterone,ghrelin, omega-3-fatty acid among others. These agentsare reported to have improved survival rates as well asquality of life. In this review, we will discuss the emergingunderstanding of the mechanisms of cancer cachexia,the current treatment options including multidisciplinarycombination therapies, as well an update on new andongoing clinical trials.

  19. Molecular Mechanisms Underlying Pituitary Pathogenesis.

    Science.gov (United States)

    Sapochnik, Melanie; Nieto, Leandro Eduardo; Fuertes, Mariana; Arzt, Eduardo

    2016-04-01

    During the last years, progress has been made on the identification of mechanisms involved in anterior pituitary cell transformation and tumorigenesis. Oncogene activation, tumor suppressor gene inactivation, epigenetic changes, and microRNAs deregulation contribute to the initiation of pituitary tumors. Despite the high prevalence of pituitary adenomas, they are mostly benign, indicating that intrinsic mechanisms may regulate pituitary cell expansion. Senescence is characterized by an irreversible cell cycle arrest and represents an important protective mechanism against malignancy. Pituitary tumor transforming gene (PTTG) is an oncogene involved in early stages of pituitary tumor development, and also triggers a senescence response by activating DNA-damage signaling pathway. Cytokines, as well as many other factors, play an important role in pituitary physiology, affecting not only cell proliferation but also hormone secretion. Special interest is focused on interleukin-6 (IL-6) because its dual function of stimulating pituitary tumor cell growth but inhibiting normal pituitary cells proliferation. It has been demonstrated that IL-6 has a key role in promoting and maintenance of the senescence program in tumors. Senescence, triggered by PTTG activation and mediated by IL-6, may be a mechanism for explaining the benign nature of pituitary tumors. PMID:26718581

  20. Molecular mechanisms and treatment options for muscle wasting eiseases

    OpenAIRE

    Rüegg, Markus A.; Glass, David J.

    2010-01-01

    Loss of muscle mass can be the consequence of pathological changes, as observed in muscular dystrophies; or it can be secondary to cachexia-inducing diseases that cause muscle atrophy, such as cancer, heart disease, or chronic obstructive pulmonary disease; or it can be a consequence of aging or simple disuse. Although muscular dystrophies are rare, muscle loss affects millions of people worldwide.Wediscuss the molecular mechanisms involved in muscular dystrophy and in muscle atrophy and pres...

  1. Cellular and molecular mechanisms in kidney fibrosis

    Science.gov (United States)

    Duffield, Jeremy S.

    2014-01-01

    Fibrosis is a characteristic feature of all forms of chronic kidney disease. Deposition of pathological matrix in the interstitial space and within the walls of glomerular capillaries as well as the cellular processes resulting in this deposition are increasingly recognized as important factors amplifying kidney injury and accelerating nephron demise. Recent insights into the cellular and molecular mechanisms of fibrogenesis herald the promise of new therapies to slow kidney disease progression. This review focuses on new findings that enhance understanding of cellular and molecular mechanisms of fibrosis, the characteristics of myofibroblasts, their progenitors, and molecular pathways regulating both fibrogenesis and its resolution. PMID:24892703

  2. Molecular Mechanisms of Green Tea Polyphenols

    OpenAIRE

    Dou, Q. Ping

    2009-01-01

    Tea, next to water, is the most popular beverage in the world. It has been suggested that tea consumption has the cancer-preventive effects. Epidemiological studies have indicated decreased cancer occurrence in people who regularly drink green tea. Research has also discovered numerous mechanisms of action to explain the biological effects of tea. The most abundant and popular compound studied in tea research is (−)-epigallocatechin-3-gallate or (−)-EGCG, which is a powerful antioxidant and c...

  3. New molecular targets against cervical cancer

    Directory of Open Access Journals (Sweden)

    Duenas-Gonzalez A

    2014-12-01

    Full Text Available Alfonso Duenas-Gonzalez,1,2 Alberto Serrano-Olvera,3 Lucely Cetina,4 Jaime Coronel4 1Unit of Biomedical Research in Cancer, Instituto de Investigaciones Biomedicas UNAM/Instituto Nacional de Cancerologia, Mexico City, 2ISSEMyM Cancer Center, Toluca, 3Medical Oncology Service, ABC Medical Center, Mexico City, 4Division of Clinical Research, Instituto Nacional de Cancerologia, Mexico City, Mexico On behalf of the Tumor Study Group Abstract: Cervical cancer is the third most commonly diagnosed cancer worldwide and the fourth leading cause of cancer death in women. Major advances but still insufficient achievements in the treatment of locally advanced and high-risk early stage patients have occurred in the last decade with the incorporation of concurrent cisplatin with radiation and, lately, gemcitabine added to cisplatin chemoradiation. Despite a number of clinical studies incorporating molecular-targeted therapy as radiosensitizers being in progress, so far, only antiangiogenic therapy with bevacizumab added to cisplatin chemoradiation has demonstrated safety and shown encouraging results in a Phase II study. In advanced disease, cisplatin doublets do not have a great impact on the natural history of the disease with median survival rates not exceeding 13 months. The first Phase III study of bevacizumab, added to cisplatin or a non-cisplatin-containing doublet, showed significant increase in both overall survival and progression-free survival. Further studies are needed before bevacizumab plus chemotherapy can be considered the standard of care for advanced disease. Characterization of the mutational landscape of cervical cancer has already been initiated, indicating that, for now, few of these targetable alterations match with available agents. Progress in both the mutational landscape knowledge and developments of novel targeted therapies may result in more effective and individualized treatments for cervical cancer. The potential efficacy of

  4. Molecular mechanisms of cryptococcal meningitis

    OpenAIRE

    Liu, Tong-Bao; Perlin, David; Xue, Chaoyang

    2012-01-01

    Fungal meningitis is a serious disease caused by a fungal infection of the central nervous system (CNS) mostly in individuals with immune system deficiencies. Fungal meningitis is often fatal without proper treatment, and the mortality rate remains unacceptably high even with antifungal drug interventions. Currently, cryptococcal meningitis is the most common fungal meningitis in HIV-1/AIDS, and its disease mechanism has been extensively studied. The key steps for fungi to infect brain and ca...

  5. Molecular markers for thyroid cancer

    International Nuclear Information System (INIS)

    The importance of the study of the thyroid nodule lies in excluding the possibility of a malignant lesion because the majority of lesions are benign but there is a malignancy risk of 5 to 10%. Most of them are well differentiated carcinomas originating in the follicular epithelium. In spite of the fact that the majority are benign lesions, distinguishing them from carcinomas is crucial to treatment and adequate follow-up. Fine-needle biopsy allows making the diagnosis in most of cases. However, this method is restricted, particularly when diagnosing follicular lesions. In an effort to improve the diagnostic accuracy of biopsy and to provide new diagnosing criteria, a number of molecular markers have been put forward, some of which has wide range of approval whereas others still awaits to be validated for further implementation. This article presented an updated review of molecular markers with higher number of evidence, more accessible and potentially usable from a methodological viewpoint for diagnosis of the thyroid nodule before surgery. The importance of the study of the thyroid nodule lies in excluding the possibility of a malignant lesion because the majority of lesions are benign but there is a malignancy risk of 5 to 10%. Most of them are well differentiated carcinomas originating in the follicular epithelium. In spite of the fact that the majority are benign lesions, distinguishing them from carcinomas is crucial to treatment and adequate follow-up. Fine-needle biopsy allows making the diagnosis in most of cases. However, this method is restricted, particularly when diagnosing follicular lesions. In an effort to improve the diagnostic accuracy of biopsy and to provide new diagnosing criteria, a number of molecular markers have been put forward, some of which has wide range of approval whereas others still awaits to be validated for further implementation. This article presented an updated review of molecular markers with higher number of evidence, more

  6. ENDOCRINE TUMOURS: Advances in the molecular pathogenesis of thyroid cancer: lessons from the cancer genome.

    Science.gov (United States)

    Riesco-Eizaguirre, Garcilaso; Santisteban, Pilar

    2016-11-01

    Thyroid cancer is the most common endocrine malignancy giving rise to one of the most indolent solid cancers, but also one of the most lethal. In recent years, systematic studies of the cancer genome, most importantly those derived from The Cancer Genome Altas (TCGA), have catalogued aberrations in the DNA, chromatin, and RNA of the genomes of thousands of tumors relative to matched normal cellular genomes and have analyzed their epigenetic and protein consequences. Cancer genomics is therefore providing new information on cancer development and behavior, as well as new insights into genetic alterations and molecular pathways. From this genomic perspective, we will review the main advances concerning some essential aspects of the molecular pathogenesis of thyroid cancer such as mutational mechanisms, new cancer genes implicated in tumor initiation and progression, the role of non-coding RNA, and the advent of new susceptibility genes in thyroid cancer predisposition. This look across these genomic and cellular alterations results in the reshaping of the multistep development of thyroid tumors and offers new tools and opportunities for further research and clinical development of novel treatment strategies. PMID:27666535

  7. Molecular mechanism of sweetness sensation.

    Science.gov (United States)

    DuBois, Grant E

    2016-10-01

    The current understanding of peripheral molecular events involved in sweet taste sensation in humans is reviewed. Included are discussions of the sweetener receptor T1R2/T1R3, its agonists, antagonists, positive allosteric modulators, the transduction of its activation in taste bud cells and the coding of its signaling to the CNS. Areas of incomplete understanding include 1) signal communication with afferent nerve fibers, 2) contrasting concentration/response (C/R) functions for high-potency (HP) sweeteners (hyperbolic) and carbohydrate (CHO) sweeteners (linear), 3) contrasting temporal profiles for HP sweeteners (delayed onset and extinction) and CHO sweeteners (rapid onset and extinction) and 4) contrasting adaptation behaviors for HP sweeteners (moderate to strong adaptation) and CHO sweeteners (low adaptation). Evidence based on the sweet water aftertastes of several novel sweetness inhibitors is presented providing new support for constitutive activity in T1R2/T1R3. And a model is developed to rationalize the linear C/R functions of CHO sweeteners and hyperbolic C/R functions of HP sweeteners, where the former may activate T1R2/T1R3 by both binding and constitutive activity modulation (i.e., without binding) and the latter activate T1R2/T1R3 only by binding. PMID:26992959

  8. Molecular pathogenesis ofsporadic colorectal cancers

    Institute of Scientific and Technical Information of China (English)

    HidetsuguYamagishi; HajimeKuroda; YasuoImai; HideyukiHiraishi

    2016-01-01

    Colorectal cancer (CRC) results from the progressive accumulation of genetic and epigenetic alterations that lead to the transformation of normal colonic mucosa to adenocarcinoma. Approximately 75% of CRCs are sporadic and occur in people without genetic predisposition or family history of CRC. During the past two decades, sporadic CRCs were classiifed into three major groups according to frequently altered/mutated genes. These genes have been identiifed by linkage analyses of cancer-prone families and by individual mutation analyses of candidate genes selected on the basis of functional data. In the ifrst half of this review, we describe the genetic pathways of sporadic CRCs and their clinicopathologic features. Recently, large-scale genome analyses have detected many infrequently mutated genes as well as a small number of frequently mutated genes. These infrequently mutated genes are likely described in a lim-ited number of pathways. Gene-oriented models of CRC progression are being replaced by pathway-oriented models. In the second half of this review, we summarize the present knowledge of this research ifeld and discuss its prospects.

  9. A refined molecular taxonomy of breast cancer. : molecular classification of breast cancer

    OpenAIRE

    Guedj, Michael; Marisa, Laëtitia; De Reynies, Aurélien; Orsetti, Béatrice; Schiappa, Renaud; Bibeau, Frédéric; MacGrogan, Gaëtan; Lerebours, Florence; Finetti, Pascal; Longy, Michel; Bertheau, Philippe; Bertrand, Françoise; Bonnet, Françoise; Martin, Anne-Laure; Feugeas, Jean-Paul

    2012-01-01

    International audience; The current histoclinical breast cancer classification is simple but imprecise. Several molecular classifications of breast cancers based on expression profiling have been proposed as alternatives. However, their reliability and clinical utility have been repeatedly questioned, notably because most of them were derived from relatively small initial patient populations. We analyzed the transcriptomes of 537 breast tumors using three unsupervised classification methods. ...

  10. Molecular Signaling Pathways Mediating Osteoclastogenesis Induced by Prostate Cancer Cells

    International Nuclear Information System (INIS)

    Advanced prostate cancer commonly metastasizes to bone leading to osteoblastic and osteolytic lesions. Although an osteolytic component governed by activation of bone resorbing osteoclasts is prominent in prostate cancer metastasis, the molecular mechanisms of prostate cancer-induced osteoclastogenesis are not well-understood. We studied the effect of soluble mediators released from human prostate carcinoma cells on osteoclast formation from mouse bone marrow and RAW 264.7 monocytes. Soluble factors released from human prostate carcinoma cells significantly increased viability of naïve bone marrow monocytes, as well as osteoclastogenesis from precursors primed with receptor activator of nuclear factor κ-B ligand (RANKL). The prostate cancer-induced osteoclastogenesis was not mediated by RANKL as it was not inhibited by osteoprotegerin (OPG). However inhibition of TGFβ receptor I (TβRI), or macrophage-colony stimulating factor (MCSF) resulted in attenuation of prostate cancer-induced osteoclastogenesis. We characterized the signaling pathways induced in osteoclast precursors by soluble mediators released from human prostate carcinoma cells. Prostate cancer factors increased basal calcium levels and calcium fluctuations, induced nuclear localization of nuclear factor of activated t-cells (NFAT)c1, and activated prolonged phosphorylation of ERK1/2 in RANKL-primed osteoclast precursors. Inhibition of calcium signaling, NFATc1 activation, and ERK1/2 phosphorylation significantly reduced the ability of prostate cancer mediators to stimulate osteoclastogenesis. This study reveals the molecular mechanisms underlying the direct osteoclastogenic effect of prostate cancer derived factors, which may be beneficial in developing novel osteoclast-targeting therapeutic approaches

  11. Molecular mechanisms of induced mutagenesis

    International Nuclear Information System (INIS)

    Genetic analysis has revealed that radiation and many chemical mutagens induce in bacteria an error-prone DNA repair process which is responsible for their mutagenic effect. The biochemical mechanism of this inducible error-prone repair has been studied by analysis of the first round of DNA synthesis on ultraviolet light-irradiated phiX174 DNA in both intact and ultraviolet light-irradiated host cells. Intracellular phiX174 DNA was extracted, subjected to isopycnic CsCl density-gradient analysis, hydroxylapatite chromatography and digestion by single-strand-specific endonuclease S1. Ultraviolet light-induced photolesions in viral DNA cause a permanent blockage of DNA synthesis in intact Escherichia coli cells. However, when host cells were irradiated and incubated to induce fully the error-prone repair system, a significant fraction of irradiated phiX174 DNA molecules can be fully replicated. Thus, inducible error-prone repair in E.coli is manifested by an increased capacity for DNA synthesis on damaged phiX174 DNA. Chloramphenicol (100 μ g/ml), which is an inhibitor of the inducible error-prone DNA repair, is also an inhibitor of this particular inducible DNA synthesis. (author)

  12. Gastric cancer-molecular and clinical dimensions.

    Science.gov (United States)

    Wadhwa, Roopma; Song, Shumei; Lee, Ju-Seog; Yao, Yixin; Wei, Qingyi; Ajani, Jaffer A

    2013-11-01

    Gastric cancer imposes a considerable health burden around the globe despite its declining incidence. The disease is often diagnosed in advanced stages and is associated with a poor prognosis for patients. An in-depth understanding of the molecular underpinnings of gastric cancer has lagged behind many other cancers of similar incidence and morbidity, owing to our limited knowledge of germline susceptibility traits for risk and somatic drivers of progression (to identify novel therapeutic targets). A few germline (PLCE1) and somatic (ERBB2, ERBB3, PTEN, PI3K/AKT/mTOR, FGF, TP53, CDH1 and MET) alterations are emerging and some are being pursued clinically. Novel somatic gene targets (ARID1A, FAT4, MLL and KMT2C) have also been identified and are of interest. Variations in the therapeutic approaches dependent on geographical region are evident for localized gastric cancer-differences that are driven by preferences for the adjuvant strategies and the extent of surgery coupled with philosophical divides. However, greater uniformity in approach has been noted in the metastatic cancer setting, an incurable condition. Having realized only modest successes, momentum is building for carrying out more phase III comparative trials, with some using biomarker-based patient selection strategies. Overall, rapid progress in biotechnology is improving our molecular understanding and can help with new drug discovery. The future prospects are excellent for defining biomarker-based subsets of patients and application of specific therapeutics. However, many challenges remain to be tackled. Here, we review representative molecular and clinical dimensions of gastric cancer.

  13. Molecular mechanisms of DNA photodamage

    Energy Technology Data Exchange (ETDEWEB)

    Starrs, S.M

    2000-05-01

    Photodamage in DNA, caused by ultraviolet (UV) light, can occur by direct excitation of the nucleobases or indirectly via the action of photosensitisers. Such, DNA photodamage can be potentially mutagenic or lethal. Among the methods available for detecting UV-induced DNA damage, gel sequencing protocols, utilising synthetic oligodeoxyribonucleotides as targets for UV radiation, allow photolesions to be mapped at nucleotide resolution. This approach has been applied to investigate both DNA damage mechanisms. Following a general overview of DNA photoreactivity, and a description of the main experimental procedures, Chapter 3 identifies the origin of an anomalous mobility shift observed in purine chemical sequence ladders that can confuse the interpretation of DNA cleavage results; measures to abolish this shift are also described. Chapters 4 and 5 examine the alkali-labile DNA damage photosensitised by representative nonsteroidal antiinflammatory drugs (NSAIDs) and the fluoroquinolone antibiotics. Suprofen was the most photoactive NSAID studied, producing different patterns of guanine-specific damage in single-stranded and duplex DNA. Uniform modification of guanine bases, typifying attack by singlet oxygen, was observed in single-stranded oligodeoxyribonucleotides. In duplex molecules, modification was limited to the 5'-G of GG doublets, which is indicative of an electron transfer. The effect of quenchers and photoproduct analysis substantiated these findings. The quinolone, nalidixic acid, behaves similarly. The random base cleavage photosensitised by the fluoroquinolones, has been attributed to free radicals produced during their photodecomposition. Chapter 6 addresses the photoreactivity of purines within unusual DNA structures formed by the repeat sequences (GGA){sub n} and (GA){sub n}, and a minihairpin. There was no definitive evidence for enhanced purine reactivity caused by direct excitation. Finally, Chapter 7 investigates the mutagenic potential of a

  14. Molecular diagnosis of prostate cancer: Topical issues

    Directory of Open Access Journals (Sweden)

    E. N. Knyazev

    2014-01-01

    Full Text Available Prostate cancer (PC is the second most common cancer and the fifth highest malignancy mortality rate in men worldwide. Although PC is detectable in 15-20% of men during life, its death risk is only about 3%. This means that not all PC cases require the same management tactics. The given review analyzes the current investigations searching for molecular biological markers to predict the course of PC and to choose its treatment policy, including that in the development of resistance to androgen-deprivation therapy.

  15. Molecular diagnosis of prostate cancer: Topical issues

    OpenAIRE

    E. N. Knyazev; K. A. Fomicheva; K. M. Nyushko; Kaprin, A. D.; B. Ya. Alekseev; M. Yu. Shkurnikov

    2014-01-01

    Prostate cancer (PC) is the second most common cancer and the fifth highest malignancy mortality rate in men worldwide. Although PC is detectable in 15-20% of men during life, its death risk is only about 3%. This means that not all PC cases require the same management tactics. The given review analyzes the current investigations searching for molecular biological markers to predict the course of PC and to choose its treatment policy, including that in the development of resistance to androge...

  16. Molecular diagnosis of prostate cancer: Topical issues

    Directory of Open Access Journals (Sweden)

    E. N. Knyazev

    2014-12-01

    Full Text Available Prostate cancer (PC is the second most common cancer and the fifth highest malignancy mortality rate in men worldwide. Although PC is detectable in 15-20% of men during life, its death risk is only about 3%. This means that not all PC cases require the same management tactics. The given review analyzes the current investigations searching for molecular biological markers to predict the course of PC and to choose its treatment policy, including that in the development of resistance to androgen-deprivation therapy.

  17. Molecular mechanism of the sweet taste enhancers

    OpenAIRE

    Feng ZHANG; Klebansky, Boris; Fine, Richard M.; Liu, Haitian; Xu, Hong; Servant, Guy; Zoller, Mark; Tachdjian, Catherine; Li, Xiaodong

    2010-01-01

    Positive allosteric modulators of the human sweet taste receptor have been developed as a new way of reducing dietary sugar intake. Besides their potential health benefit, the sweet taste enhancers are also valuable tool molecules to study the general mechanism of positive allosteric modulations of T1R taste receptors. Using chimeric receptors, mutagenesis, and molecular modeling, we reveal how these sweet enhancers work at the molecular level. Our data argue that the sweet enhancers follow a...

  18. Cellular and molecular aspects of gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Malcolm G Smith; Georgina L Hold; Eiichi Tahara; Emad M El-Omar

    2006-01-01

    Gastric cancer remains a global killer with a shifting burden from the developed to the developing world.The cancer develops along a multistage process that is defined by distinct histological and pathophysiological phases. Several genetic and epigenetic alterations mediate the transition from one stage to another and these include mutations in oncogenes, tumour suppressor genes and cell cycle and mismatch repair genes. The most significant advance in the fight against gastric caner came with the recognition of the role of Helicobacter pylori (H pylori) as the most important acquired aetiological agent for this cancer. Recent work has focussed on elucidating the complex host/microbial interactions that underlie the neoplastic process. There is now considerable insight into the pathogenesis of this cancer and the prospect of preventing and eradicating the disease has become a reality. Perhaps more importantly, the study of H pylori-induced gastric carcinogenesis offers a paradigm for understanding more complex human cancers. In this review, we examine the molecular and cellular events that underlie H pyloriinduced gastric cancer.

  19. Molecular Imaging of Pulmonary Cancer and Inflammation

    OpenAIRE

    Divgi, Chaitanya R.

    2009-01-01

    Molecular imaging (MI) may be defined as imaging in vivo using molecules that report on biologic function. This review will focus on the clinical use of radioactive tracers (nonpharmacologic amounts of compounds labeled with a radioactive substance) that permit external imaging using single photon emission computed tomography (planar, SPECT) or positron emission tomography (PET) imaging. Imaging of lung cancer has been revolutionized with the use of fluorine-18–labeled fluorodeoxyglucose (18F...

  20. CPFP Summer Curriculum: Molecular Prevention Course | Division of Cancer Prevention

    Science.gov (United States)

    This Cancer Prevention Fellowship Program (CPFP) one-week course on molecular aspects of cancer prevention follows the Principles and Practice of Cancer Prevention and Control course. It provides a strong background about molecular biology and genetics of cancer, and an overview of cutting-edge research and techniques in the fields of molecular epidemiology, biomarkers, multi-omic, and translational research. The following topics will be typically presented: |

  1. Molecular basis of the triple negative breast cancer

    OpenAIRE

    Ayse Feyda Nursal

    2015-01-01

    Breast cancer is the most common type of cancer in women and more than 1 million breast cancer cases are diagnosed each year all over the world. Breast cancer is a complex and heterogeneous disease in terms of its molecular structure, mutation type, metastase properties, clinical course and therapeutic response. Breast cancer is divided into subtypes based on expression properties of molecular markers as estrogen receptor, progestron receptor, human epidermal growth factor receptor 2. Triple-...

  2. Molecular aspects of prostate cancer: implications for future directions

    Directory of Open Access Journals (Sweden)

    Etel R. P. Gimba

    2003-10-01

    Full Text Available Many studies have been developed trying to understand the complex molecular mechanisms involved in oncogenesis and progression of prostate cancer (PCa. Current biotechnological methodologies, especially genomic studies, are adding important aspects to this area. The construction of extensive DNA sequence data and gene expression profiles have been intensively explored to search for candidate biomarkers to evaluate PCa. The use of DNA micro-array robotic systems constitutes a powerful approach to simultaneously monitor the expression of a great number of genes. The resulting gene expressing profiles can be used to specifically describe tumor staging and response to cancer therapies. Also, it is possible to follow PCa pathological properties and to identify genes that anticipate the behavior of clinical disease. The molecular pathogenesis of PCa involves many contributing factors, such as alterations in signal transduction pathways, angiogenesis, adhesion molecules expression and cell cycle control. Also, molecular studies are making clear that many genes, scattered through several different chromosomal regions probably cause predisposition to PCa. The discovery of new molecular markers for PCa is another relevant advance resulting from molecular biology studies of prostate tumors. Interesting tissue and serum markers have been reported, resulting in many cases in useful novelties to diagnostic and prognostic approaches to follow-up PCa. Finally, gene therapy comes as an important approach for therapeutic intervention in PCa. Clinical trials for PCa have been demonstrating that gene therapy is relatively safe and well tolerated, although some improvements are yet to be developed.

  3. Cellular and molecular mechanisms underlie the anti-tumor activities exerted by Walterinnesia aegyptia venom combined with silica nanoparticles against multiple myeloma cancer cell types.

    Directory of Open Access Journals (Sweden)

    Gamal Badr

    +NP and the underlying mechanisms against myeloma cancer cells.

  4. Molecular mechanisms for tumour resistance to chemotherapy.

    Science.gov (United States)

    Pan, Shu-Ting; Li, Zhi-Ling; He, Zhi-Xu; Qiu, Jia-Xuan; Zhou, Shu-Feng

    2016-08-01

    Chemotherapy is one of the prevailing methods used to treat malignant tumours, but the outcome and prognosis of tumour patients are not optimistic. Cancer cells gradually generate resistance to almost all chemotherapeutic drugs via a variety of distinct mechanisms and pathways. Chemotherapeutic resistance, either intrinsic or acquired, is caused and sustained by reduced drug accumulation and increased drug export, alterations in drug targets and signalling transduction molecules, increased repair of drug-induced DNA damage, and evasion of apoptosis. In order to better understand the mechanisms of chemoresistance, this review highlights our current knowledge of the role of altered drug metabolism and transport and deregulation of apoptosis and autophagy in the development of tumour chemoresistance. Reduced intracellular activation of prodrugs (e.g. thiotepa and tegafur) or enhanced drug inactivation by Phase I and II enzymes contributes to the development of chemoresistance. Both primary and acquired resistance can be caused by alterations in the transport of anticancer drugs which is mediated by a variety of drug transporters such as P-glycoprotein (P-gp), multidrug resistance associated proteins, and breast cancer resistance protein. Presently there is a line of evidence indicating that deregulation of programmed cell death including apoptosis and autophagy is also an important mechanism for tumour resistance to anticancer drugs. Reversal of chemoresistance is likely via pharmacological and biological approaches. Further studies are warranted to grasp the full picture of how each type of cancer cells develop resistance to anticancer drugs and to identify novel strategies to overcome it.

  5. Molecular mechanisms for tumour resistance to chemotherapy.

    Science.gov (United States)

    Pan, Shu-Ting; Li, Zhi-Ling; He, Zhi-Xu; Qiu, Jia-Xuan; Zhou, Shu-Feng

    2016-08-01

    Chemotherapy is one of the prevailing methods used to treat malignant tumours, but the outcome and prognosis of tumour patients are not optimistic. Cancer cells gradually generate resistance to almost all chemotherapeutic drugs via a variety of distinct mechanisms and pathways. Chemotherapeutic resistance, either intrinsic or acquired, is caused and sustained by reduced drug accumulation and increased drug export, alterations in drug targets and signalling transduction molecules, increased repair of drug-induced DNA damage, and evasion of apoptosis. In order to better understand the mechanisms of chemoresistance, this review highlights our current knowledge of the role of altered drug metabolism and transport and deregulation of apoptosis and autophagy in the development of tumour chemoresistance. Reduced intracellular activation of prodrugs (e.g. thiotepa and tegafur) or enhanced drug inactivation by Phase I and II enzymes contributes to the development of chemoresistance. Both primary and acquired resistance can be caused by alterations in the transport of anticancer drugs which is mediated by a variety of drug transporters such as P-glycoprotein (P-gp), multidrug resistance associated proteins, and breast cancer resistance protein. Presently there is a line of evidence indicating that deregulation of programmed cell death including apoptosis and autophagy is also an important mechanism for tumour resistance to anticancer drugs. Reversal of chemoresistance is likely via pharmacological and biological approaches. Further studies are warranted to grasp the full picture of how each type of cancer cells develop resistance to anticancer drugs and to identify novel strategies to overcome it. PMID:27097837

  6. Molecular mechanism for the umami taste synergism

    OpenAIRE

    Feng ZHANG; Klebansky, Boris; Fine, Richard M.; Xu, Hong; Pronin, Alexey; Liu, Haitian; Tachdjian, Catherine; Li, Xiaodong

    2008-01-01

    Umami is one of the 5 basic taste qualities. The umami taste of L-glutamate can be drastically enhanced by 5′ ribonucleotides and the synergy is a hallmark of this taste quality. The umami taste receptor is a heteromeric complex of 2 class C G-protein-coupled receptors, T1R1 and T1R3. Here we elucidate the molecular mechanism of the synergy using chimeric T1R receptors, site-directed mutagenesis, and molecular modeling. We propose a cooperative ligand-binding model involving the Venus flytrap...

  7. SU-E-I-39: Molecular Image Guided Cancer Stem Cells Therapy

    International Nuclear Information System (INIS)

    Purpose: Cancer stem cells resistance to radiation is a problematic issue that has caused a big fail in cancer treatment. Methods: As a primary work, molecular imaging can indicate the main mechanisms of radiation resistance of cancer stem cells. By developing and commissioning new probes and nanomolecules and biomarkers, radiation scientist will able to identify the essential pathways of radiation resistance of cancer stem cells. As the second solution, molecular imaging is a best way to find biological target volume and delineate cancer stem cell tissues. In the other hand, by molecular imaging techniques one can image the treatment response in tumor and also in normal tissue. In this issue, the response of cancer stem cells to radiation during therapy course can be imaged, also the main mechanisms of radiation resistance and finding the best radiation modifiers (sensitizers) can be achieved by molecular imaging modalities. In adaptive radiotherapy the molecular imaging plays a vital role to have higher tumor control probability by delivering high radiation doses to cancer stem cells in any time of treatment. The outcome of a feasible treatment is dependent to high cancer stem cells response to radiation and removing all of which, so a good imaging modality can show this issue and preventing of tumor recurrence and metastasis. Results: Our results are dependent to use of molecular imaging as a new modality in the clinic. We propose molecular imaging as a new radiobiological technique to solve radiation therapy problems due to cancer stem cells. Conclusion: Molecular imaging guided cancer stem cell diagnosis and therapy is a new approach in the field of cancer treatment. This new radiobiological imaging technique should be developed in all clinics as a feasible tool that is more biological than physical imaging

  8. SU-E-I-39: Molecular Image Guided Cancer Stem Cells Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Abdollahi, H

    2014-06-01

    Purpose: Cancer stem cells resistance to radiation is a problematic issue that has caused a big fail in cancer treatment. Methods: As a primary work, molecular imaging can indicate the main mechanisms of radiation resistance of cancer stem cells. By developing and commissioning new probes and nanomolecules and biomarkers, radiation scientist will able to identify the essential pathways of radiation resistance of cancer stem cells. As the second solution, molecular imaging is a best way to find biological target volume and delineate cancer stem cell tissues. In the other hand, by molecular imaging techniques one can image the treatment response in tumor and also in normal tissue. In this issue, the response of cancer stem cells to radiation during therapy course can be imaged, also the main mechanisms of radiation resistance and finding the best radiation modifiers (sensitizers) can be achieved by molecular imaging modalities. In adaptive radiotherapy the molecular imaging plays a vital role to have higher tumor control probability by delivering high radiation doses to cancer stem cells in any time of treatment. The outcome of a feasible treatment is dependent to high cancer stem cells response to radiation and removing all of which, so a good imaging modality can show this issue and preventing of tumor recurrence and metastasis. Results: Our results are dependent to use of molecular imaging as a new modality in the clinic. We propose molecular imaging as a new radiobiological technique to solve radiation therapy problems due to cancer stem cells. Conclusion: Molecular imaging guided cancer stem cell diagnosis and therapy is a new approach in the field of cancer treatment. This new radiobiological imaging technique should be developed in all clinics as a feasible tool that is more biological than physical imaging.

  9. Emerging Anticancer Potentials of Goniothalamin and Its Molecular Mechanisms

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Seyed

    2014-01-01

    Full Text Available The treatment of most cancers is still inadequate, despite tremendous steady progress in drug discovery and effective prevention. Nature is an attractive source of new therapeutics. Several medicinal plants and their biomarkers have been widely used for the treatment of cancer with less known scientific basis of their functioning. Although a wide array of plant derived active metabolites play a role in the prevention and treatment of cancer, more extensive scientific evaluation of their mechanisms is still required. Styryl-lactones are a group of secondary metabolites ubiquitous in the genus Goniothalamus that have demonstrated to possess antiproliferative activity against cancer cells. A large body of evidence suggests that this activity is associated with the induction of apoptosis in target cells. In an effort to promote further research on the genus Goniothalamus, this review offers a broad analysis of the current knowledge on Goniothalamin (GTN or 5, 6, dihydro-6-styryl-2-pyronone (C13H12O2, a natural occurring styryl-lactone. Therefore, it includes (i the source of GTN and other metabolites; (ii isolation, purification, and (iii the molecular mechanisms of actions of GTN, especially the anticancer properties, and summarizes the role of GTN which is crucial for drug design, development, and application in future for well-being of humans.

  10. Mechanisms of inherited cancer susceptibility

    Institute of Scientific and Technical Information of China (English)

    Shirley HODGSON

    2008-01-01

    A small proportion of many cancers are due to inherited mutations in genes, which result in a high risk to the individual of developing specific cancers. There are several classes of genes that may be involved: tumour suppressor genes, oncogenes, genes encoding proteins involved in DNA repair and cell cycle control, and genes involved in stimulating the angiogenic pathway. Alterations in susceptibility to cancer may also be due to variations in genes involved in carcinogen metabolism. This review discusses examples of some of these genes and the associated clinical conditions caused by the inheritance of mutations in such genes.

  11. Molecular Taxonomy and Tumourigenesis of Colorectal Cancer.

    Science.gov (United States)

    Biswas, S; Holyoake, D; Maughan, T S

    2016-02-01

    Over the last 5 years there has been a surge in interest in the molecular classification of colorectal cancer. The effect of molecular subtyping on current treatment decisions is limited to avoidance of adjuvant 5-fluorouracil chemotherapy in stage II microsatellite unstable-high disease and avoidance of epidermal growth factor receptor-targeted antibodies in extended RAS mutant tumours. The emergence of specific novel combination therapy for the BRAF-mutant cohort and of the microsatellite unstable-high cohort as a responsive group to immune checkpoint inhibition shows the growing importance of a clinically relevant molecular taxonomy. Clinical trials such as the Medical Research Council FOCUS4 trial using biomarkers to select patients for specific therapies are currently open and testing such approaches. The integration of mutation, gene expression and pathological analyses is refining our understanding of the biological subtypes within colorectal cancer. Sharing of data sets of parallel sequencing and gene expression of thousands of cancers among independent groups has allowed the description of disease subsets and the need for a validated consensus classification has become apparent. This biological understanding of the disease is a key step forward in developing a stratified approach to patient management. The discovery of stratifiers that predict a response to existing and emerging therapies will enable better use of these treatments. Improved scientific understanding of the biological characteristics of poorly responsive subgroups will facilitate the design of novel biologically rational combinations. Novel treatment regimens, including the combination of new drugs with radiation, and the discovery and validation of their associated predictive biomarkers will gradually lead to improved outcomes from therapy.

  12. Oral cancer: molecular technologies for risk assessment and diagnosis

    Institute of Scientific and Technical Information of China (English)

    Wan Tao Chen

    2008-01-01

    @@ Purpose: The effective biomarkers related to diagnosis, metastasis, drug resistance and irradiation sensitivity of oral cancers will help the pathologist and oncologist to determine the molecular taxonomy diagnosis and design the individualization treatment for the patients with oral cancers.

  13. Molecular Imaging of Biomarkers in Breast Cancer

    Science.gov (United States)

    Ulaner, Gary A.; Riedl, Chris C.; Dickler, Maura N.; Jhaveri, Komal; Pandit-Taskar, Neeta; Weber, Wolfgang

    2016-01-01

    The success of breast cancer therapy is ultimately defined by clinical endpoints such as survival. It is valuable to have biomarkers that can predict the most efficacious therapies or measure response to therapy early in the course of treatment. Molecular imaging has a promising role in complementing and overcoming some of the limitations of traditional biomarkers by providing the ability to perform noninvasive, repeatable whole-body assessments. The potential advantages of imaging biomarkers are obvious and initial clinical studies have been promising, but proof of clinical utility still requires prospective multicenter clinical trials. PMID:26834103

  14. Molecular mechanism for the umami taste synergism.

    Science.gov (United States)

    Zhang, Feng; Klebansky, Boris; Fine, Richard M; Xu, Hong; Pronin, Alexey; Liu, Haitian; Tachdjian, Catherine; Li, Xiaodong

    2008-12-30

    Umami is one of the 5 basic taste qualities. The umami taste of L-glutamate can be drastically enhanced by 5' ribonucleotides and the synergy is a hallmark of this taste quality. The umami taste receptor is a heteromeric complex of 2 class C G-protein-coupled receptors, T1R1 and T1R3. Here we elucidate the molecular mechanism of the synergy using chimeric T1R receptors, site-directed mutagenesis, and molecular modeling. We propose a cooperative ligand-binding model involving the Venus flytrap domain of T1R1, where L-glutamate binds close to the hinge region, and 5' ribonucleotides bind to an adjacent site close to the opening of the flytrap to further stabilize the closed conformation. This unique mechanism may apply to other class C G-protein-coupled receptors.

  15. Molecular mechanism of the sweet taste enhancers.

    Science.gov (United States)

    Zhang, Feng; Klebansky, Boris; Fine, Richard M; Liu, Haitian; Xu, Hong; Servant, Guy; Zoller, Mark; Tachdjian, Catherine; Li, Xiaodong

    2010-03-01

    Positive allosteric modulators of the human sweet taste receptor have been developed as a new way of reducing dietary sugar intake. Besides their potential health benefit, the sweet taste enhancers are also valuable tool molecules to study the general mechanism of positive allosteric modulations of T1R taste receptors. Using chimeric receptors, mutagenesis, and molecular modeling, we reveal how these sweet enhancers work at the molecular level. Our data argue that the sweet enhancers follow a similar mechanism as the natural umami taste enhancer molecules. Whereas the sweeteners bind to the hinge region and induce the closure of the Venus flytrap domain of T1R2, the enhancers bind close to the opening and further stabilize the closed and active conformation of the receptor.

  16. Molecular mechanism and regulation of autophagy

    Institute of Scientific and Technical Information of China (English)

    Ya-ping YANG; Zhong-qin LIANG; Zhen-lun GU; Zheng-hong QIN

    2005-01-01

    Autophagy is a major cellular pathway for the degradation of long-lived proteins and cytoplasmic organelles in eukaryotic cells. A large number of intracellular/extracellular stimuli, including amino acid starvation and invasion of microorganisms, are able to induce the autophagic response in cells. The discovery of the ATG genes in yeast has greatly advanced our understanding of the molecular mechanisms participating in autophagy and the genes involved in regulating the autophagic pathway. Many yeast genes have mammalian homologs,suggesting that the basic machinery for autophagy has been evolutionarily conserved along the eukaryotic phylum. The regulation of autophagy is a very complex process. Many signaling pathways, including target of rapamycin (TOR) or mammalian target of rapamycin (mTOR), phosphatidylinositol 3-kinase-I (PI3K-I)/PKB, GTPases, calcium and protein synthesis all play important roles in regulating autophagy. The molecular mechanisms and regulation of autophagy are discussed in this review.

  17. Molecular mechanisms of amyloid self-regulation

    OpenAIRE

    Landreh, Michael

    2012-01-01

    Amyloid is associated with both pathological protein deposits and the formation of functional protein structures. Therefore, several strategies have evolved to control the formation or inhibition of amyloid in vivo. In this thesis, three separate systems were investigated in which amyloidogenic protein segments are coupled to regulatory elements that prevent or promote fibrillation. We describe the molecular mechanism for how (a) a propeptide segment prevents the uncontrolled a...

  18. Cellular and molecular mechanisms in kidney fibrosis

    OpenAIRE

    Duffield, Jeremy S.

    2014-01-01

    Fibrosis is a characteristic feature of all forms of chronic kidney disease. Deposition of pathological matrix in the interstitial space and within the walls of glomerular capillaries as well as the cellular processes resulting in this deposition are increasingly recognized as important factors amplifying kidney injury and accelerating nephron demise. Recent insights into the cellular and molecular mechanisms of fibrogenesis herald the promise of new therapies to slow kidney disease progressi...

  19. Molecular Mechanism of Biological Proton Transport

    Energy Technology Data Exchange (ETDEWEB)

    Pomes, R.

    1998-09-01

    Proton transport across lipid membranes is a fundamental aspect of biological energy transduction (metabolism). This function is mediated by a Grotthuss mechanism involving proton hopping along hydrogen-bonded networks embedded in membrane-spanning proteins. Using molecular simulations, the authors have explored the structural, dynamic, and thermodynamic properties giving rise to long-range proton translocation in hydrogen-bonded networks involving water molecules, or water wires, which are emerging as ubiquitous H{sup +}-transport devices in biological systems.

  20. Molecular markers′ progress of breast cancer treatment efficacy

    OpenAIRE

    Dan Wang; Jingwei Xu; Guang Shi; Guanghao Yin

    2015-01-01

    Breast cancer is a famous malignant tumor which is caused by varieties of mutation in multiple genes. In order to detect breast cancer in an earlier time and take appropriate treatment which includes  predicting treatment efficacy, we need a more accurate method of discovering the occurrence of breast cancer. With the development of molecular biology and biological detection technologies continue to emerge, molecular markers of breast cancer have gaining more and more widespread attention, an...

  1. Molecular mechanism of magnet formation in bacteria.

    Science.gov (United States)

    Matsunaga, T; Sakaguchi, T

    2000-01-01

    Magnetic bacteria have an ability to synthesize intracellular ferromagnetic crystalline particles consisting of magnetite (Fe3O4) or greigite (Fe3S4) which occur within a specific size range (50-100 nm). Bacterial magnetic particles (BMPs) can be distinguished by the regular morphology and the presence of an thin organic membrane enveloping crystals from abiologically formed magnetite. The particle is the smallest magnetic crystal that has a regular morphology within the single domain size. Therefore, BMPs have an unfathomable amount of potential value for various technological applications not only scientific interests. However, the molecular and genetic mechanism of magnetite biomineralization is hardly understood although iron oxide formation occurs widely in many higher animals as well as microorganisms. In order to elucidate the molecular and genetic mechanisms of magnetite biomineralization, a magnetic bacterium Magnetospirillum sp. AMB-1, for which gene transfer and transposon mutagenesis techniques had been recently developed, has been used as a model organism. Several findings and information on the BMPs formation process have been obtained within this decade by means of studies with this model organism and its related one. Biomineralization mechanism and potential availability in biotechnology of bacterial magnets have been elucidated through molecular and genetic approach. PMID:16232810

  2. The mTOR Pathway and the Role of Energy Balance Throughout Life in Colorectal Cancer Etiology and Prognosis: Unravelling Mechanisms Through a Multidimensional Molecular Epidemiologic Approach

    OpenAIRE

    Weijenberg, Matty P.; Hughes, Laura A. E.; Bours, Martijn J. L.; Simons, Colinda C. J. M.; van Engeland, Manon; van den Brandt, Piet A.

    2013-01-01

    Timing of exposure to lifestyle factors that influence energy balance may differentially affect colorectal cancer (CRC) risk and prognosis. Caloric restriction in youth and short stature, as markers of early-life exposures, have shown to decrease CRC risk, whereas large body size and low physical activity levels in adulthood are established risk factors for CRC. Regarding prognosis, overweight, sarcopenia, and their co-occurrence (sarcopenic obesity) may negatively influence the health and qu...

  3. Molecular profiling of childhood cancer: Biomarkers and novel therapies

    Directory of Open Access Journals (Sweden)

    Federica Saletta

    2014-06-01

    General significance: The increasing recognition of the heterogeneity of molecular causes of cancer favors the continued development of molecularly targeted agents, and their transfer to pediatric and adolescent populations.

  4. Fecal Molecular Markers for Colorectal Cancer Screening

    Directory of Open Access Journals (Sweden)

    Rani Kanthan

    2012-01-01

    Full Text Available Despite multiple screening techniques, including colonoscopy, flexible sigmoidoscopy, radiological imaging, and fecal occult blood testing, colorectal cancer remains a leading cause of death. As these techniques improve, their sensitivity to detect malignant lesions is increasing; however, detection of precursor lesions remains problematic and has generated a lack of general acceptance for their widespread usage. Early detection by an accurate, noninvasive, cost-effective, simple-to-use screening technique is central to decreasing the incidence and mortality of this disease. Recent advances in the development of molecular markers in faecal specimens are encouraging for its use as a screening tool. Genetic mutations and epigenetic alterations that result from the carcinogenetic process can be detected by coprocytobiology in the colonocytes exfoliated from the lesion into the fecal matter. These markers have shown promising sensitivity and specificity in the detection of both malignant and premalignant lesions and are gaining popularity as a noninvasive technique that is representative of the entire colon. In this paper, we summarize the genetic and epigenetic fecal molecular markers that have been identified as potential targets in the screening of colorectal cancer.

  5. Molecular mechanics of mussel adhesion proteins

    Science.gov (United States)

    Qin, Zhao; Buehler, Markus J.

    2014-01-01

    Mussel foot protein (mfp), a natural glue produced by marine mussel, is an intriguing material because of its superior ability for adhesion in various environments. For example, a very small amount of this material is sufficient to affix a mussel to a substrate in water, providing structural support under extreme forces caused by the dynamic effects of waves. Towards a more complete understanding of its strength and underwater workability, it is necessary to understand the microscropic mechanisms by which the protein structure interacts with various substrates. However, none of the mussel proteins' structure is known, preventing us from directly using atomistic modeling to probe their structural and mechanical properties. Here we use an advanced molecular sampling technique to identify the molecular structures of two mussel foot proteins (mfp-3 and mfp-5) and use those structures to study their mechanics of adhesion, which is then incorporated into a continuum model. We calculate the adhesion energy of the mussel foot protein on a silica substrate, compute the adhesion strength based on results obtained from molecular modeling, and compare with experimental data. Our results show good agreement with experimental measurements, which validates the multiscale model. We find that the molecular structure of the folded mussel foot protein (ultimately defined by its genetic sequence) favors strong adhesion to substrates, where L-3,4-dihydroxyphenylalanine (or DOPA) protein subunits work in a cooperative manner to enhance adhesion. Our experimental data suggests a peak attachment force of 0.4±0.1 N, which compares favorably with the prediction from the multiscale model of Fc=0.21-0.33 N. The principles learnt from those results could guide the fabrication of new interfacial materials (e.g. composites) to integrate organic with inorganic surfaces in an effective manner.

  6. Antineoplastic mechanisms of Iodine in cancers that take up Iodine

    Directory of Open Access Journals (Sweden)

    Carmen Aceves

    2015-12-01

    Full Text Available Purpose: In addition to being a component of thyroid hormone (TH, iodine can be an antioxidant as well as an antiproliferative and differentiation agent that helps to maintain the integrity of several organs with the ability to take up iodine.Methods and Results: Studies from our laboratory shown that in preclinical (cell culture, induced animal cancer and xenographs and clinical studies (mammary cancer protocol, molecular iodine (I2 supplementation exerts suppressive effects on implantation, development, and progression of cancer neoplasias. These effects can be mediated by a variety of mechanisms and pathways, including direct actions, in which the oxidized iodine modulates the immune/tumor response and through iodolipid formation and the activation of peroxisome proliferator-activated receptors type gamma (PPARγ triggering apoptotic and/or differentiation pathways.Conclusion: The absence of side effects and the easy availability and handling of I2 have allowed the establishment of clinical protocols to utilize I2 supplementation as an adjuvant in therapies against cancers that take up iodine.-----------------------------------------Cite this article as:  Aceves C, Anguiano B. Antineoplastic mechanisms of Iodine in cancers that take up Iodine. Int J Cancer Ther Oncol 2015; 3(4:3401.[This abstract was presented at the BIT’s 8th Annual World Cancer Congress, which was held from May 15-17, 2015 in Beijing, China.

  7. Epigenetic: a molecular link between testicular cancer and environmental exposures?

    Directory of Open Access Journals (Sweden)

    Aurelie eVega

    2012-11-01

    Full Text Available In the last decades, studies in rodents have highlighted links between in utero and/or neonatal exposures to molecules that alter endocrine functions and the development of genital tract abnormalities, such as cryptorchidism, hypospadias, and impaired spermatogenesis. Most of these molecules, called endocrine disrupters (EDs exert estrogenic and/or antiandrogenic activities. These data led to the hypothesis of the Testicular Dysgenesis Syndrome which postulates that these disorders are one clinical entity and are linked by epidemiological and pathophysiological relations. Futhermore, infertility has been stated as a risk factor for testicular cancer. The incidence of testicular cancer has been increasing over the past decades. Most of testicular germ cell cancers develop through a pre-invasive carcinoma in situ (CIS from fetal germ cells (primordial germ cell or gonocyte. During their development, fetal germ cells undergo epigenetic modifications. Interestingly, several lines of evidence have shown that gene regulation through epigenetic mechanisms (DNA and histone modifications plays an important role in normal development as well as in various diseases, including testicular cancer.Here we will review chromatin modifications which can affect testicular physiology leading to the development of testicular cancer; and highlight potential molecular pathways involved in these alterations in the context of environmental exposures.

  8. Understanding the molecular pathogenesis and prognostics of bladder cancer: an overview.

    Science.gov (United States)

    Zhao, Ming; He, Xiang-Lei; Teng, Xiao-Dong

    2016-02-01

    The knowledge of cellular mechanisms in malignances of the bladder has grown exponentially. Molecular technologies have led to the discovery of the molecular pathways distinguishing low-and high-grade urothelial neoplasms. This trend portends the future in which the classification and diagnosis of the bladder tumors through morphologic analysis will be supported by molecular information correlating with prognosis and targeted therapy. This article outlines tumor molecular pathology of bladder cancer with an emphasis on several promising candidate biomarkers that may soon make their transition to the realm of clinical management of bladder cancer.

  9. Molecular Mechanisms in Exercise-Induced Cardioprotection

    Directory of Open Access Journals (Sweden)

    Saeid Golbidi

    2011-01-01

    Full Text Available Physical inactivity is increasingly recognized as modifiable behavioral risk factor for cardiovascular diseases. A partial list of proposed mechanisms for exercise-induced cardioprotection include induction of heat shock proteins, increase in cardiac antioxidant capacity, expression of endoplasmic reticulum stress proteins, anatomical and physiological changes in the coronary arteries, changes in nitric oxide production, adaptational changes in cardiac mitochondria, increased autophagy, and improved function of sarcolemmal and/or mitochondrial ATP-sensitive potassium channels. It is currently unclear which of these protective mechanisms are essential for exercise-induced cardioprotection. However, most investigations focus on sarcolemmal KATP channels, NO production, and mitochondrial changes although it is very likely that other mechanisms may also exist. This paper discusses current information about these aforementioned topics and does not consider potentially important adaptations within blood or the autonomic nervous system. A better understanding of the molecular basis of exercise-induced cardioprotection will help to develop better therapeutic strategies.

  10. Molecular mechanisms for protein-encoded inheritance

    Energy Technology Data Exchange (ETDEWEB)

    Wiltzius, Jed J.W.; Landau, Meytal; Nelson, Rebecca; Sawaya, Michael R.; Apostol, Marcin I.; Goldschmidt, Lukasz; Soriaga, Angela B.; Cascio, Duilio; Rajashankar, Kanagalaghatta; Eisenberg, David; (Cornell); (HHMI)

    2009-12-01

    In prion inheritance and transmission, strains are phenotypic variants encoded by protein 'conformations'. However, it is unclear how a protein conformation can be stable enough to endure transmission between cells or organisms. Here we describe new polymorphic crystal structures of segments of prion and other amyloid proteins, which offer two structural mechanisms for the encoding of prion strains. In packing polymorphism, prion strains are encoded by alternative packing arrangements (polymorphs) of {beta}-sheets formed by the same segment of a protein; in segmental polymorphism, prion strains are encoded by distinct {beta}-sheets built from different segments of a protein. Both forms of polymorphism can produce enduring conformations capable of encoding strains. These molecular mechanisms for transfer of protein-encoded information into prion strains share features with the familiar mechanism for transfer of nucleic acid-encoded information into microbial strains, including sequence specificity and recognition by noncovalent bonds.

  11. Molecular Mechanisms of Renal Ischemic Conditioning Strategies.

    Science.gov (United States)

    Kierulf-Lassen, Casper; Nieuwenhuijs-Moeke, Gertrude J; Krogstrup, Nicoline V; Oltean, Mihai; Jespersen, Bente; Dor, Frank J M F

    2015-01-01

    Ischemia-reperfusion injury is the leading cause of acute kidney injury in a variety of clinical settings such as renal transplantation and hypovolemic and/or septic shock. Strategies to reduce ischemia-reperfusion injury are obviously clinically relevant. Ischemic conditioning is an inherent part of the renal defense mechanism against ischemia and can be triggered by short periods of intermittent ischemia and reperfusion. Understanding the signaling transduction pathways of renal ischemic conditioning can promote further clinical translation and pharmacological advancements in this era. This review summarizes research on the molecular mechanisms underlying both local and remote ischemic pre-, per- and postconditioning of the kidney. The different types of conditioning strategies in the kidney recruit similar powerful pro-survival mechanisms. Likewise, renal ischemic conditioning mobilizes many of the same protective signaling pathways as in other organs, but differences are recognized. PMID:26330099

  12. Inhibitory effects of polyphenol-enriched extract from Ziyang tea against human breast cancer MCF-7 cells through reactive oxygen species-dependent mitochondria molecular mechanism

    Directory of Open Access Journals (Sweden)

    Wenfeng Li

    2016-07-01

    Full Text Available A polyphenol-enriched extract from selenium-enriched Ziyang green tea (ZTP was selected to evaluate its antitumor effects against human breast cancer MCF-7 cells. In ZTP, (−-epigallocatechin gallate (28.2% was identified as the major catechin, followed by (−-epigallocatechin (5.7% and (−-epicatechin gallate (12.6%. ZTP was shown to inhibit MCF-7 cell proliferation (half maximal inhibitory concentration, IC50 = 172.2 μg/mL by blocking cell-cycle progression at the G0/G1 phase and inducing apoptotic death. Western blotting assay indicated that ZTP induced cell-cycle arrest by upregulation of p53 and reduced the expression of CDK2 in MCF-7 cells. ZTP-caused cell apoptosis was associated with an increase in Bax/Bcl-2 ratio, and activation of caspase-3 and -9. MCF-7 cells treated with ZTP also showed an overproduction of reactive oxygen species, suggesting that reactive oxygen species played an important role in the induction of apoptosis in MCF-7 cells. This is the first report showing that ZTP is a potential novel dietary agent for cancer chemoprevention or chemotherapy.

  13. Biological Applications of Hybrid Quantum Mechanics/Molecular Mechanics Calculation

    Directory of Open Access Journals (Sweden)

    Jiyoung Kang

    2012-01-01

    Full Text Available Since in most cases biological macromolecular systems including solvent water molecules are remarkably large, the computational costs of performing ab initio calculations for the entire structures are prohibitive. Accordingly, QM calculations that are jointed with MM calculations are crucial to evaluate the long-range electrostatic interactions, which significantly affect the electronic structures of biological macromolecules. A UNIX-shell-based interface program connecting the quantum mechanics (QMs and molecular mechanics (MMs calculation engines, GAMESS and AMBER, was developed in our lab. The system was applied to a metalloenzyme, azurin, and PU.1-DNA complex; thereby, the significance of the environmental effects on the electronic structures of the site of interest was elucidated. Subsequently, hybrid QM/MM molecular dynamics (MD simulation using the calculation system was employed for investigation of mechanisms of hydrolysis (editing reaction in leucyl-tRNA synthetase complexed with the misaminoacylated tRNALeu, and a novel mechanism of the enzymatic reaction was revealed. Thus, our interface program can play a critical role as a powerful tool for state-of-the-art sophisticated hybrid ab initio QM/MM MD simulations of large systems, such as biological macromolecules.

  14. Molecular diagnosis for personalized target therapy in gastric cancer.

    Science.gov (United States)

    Cho, Jae Yong

    2013-09-01

    Gastric cancer is the second leading cause of cancer-related deaths worldwide. In advanced and metastatic gastric cancer, the conventional chemotherapy with limited efficacy shows an overall survival period of about 10 months. Patient specific and effective treatments known as personalized cancer therapy is of significant importance. Advances in high-throughput technologies such as microarray and next generation sequencing for genes, protein expression profiles and oncogenic signaling pathways have reinforced the discovery of treatment targets and personalized treatments. However, there are numerous challenges from cancer target discoveries to practical clinical benefits. Although there is a flood of biomarkers and target agents, only a minority of patients are tested and treated accordingly. Numerous molecular target agents have been under investigation for gastric cancer. Currently, targets for gastric cancer include the epidermal growth factor receptor family, mesenchymal-epithelial transition factor axis, and the phosphatidylinositol 3-kinase-AKT-mammalian target of rapamycin pathways. Deeper insights of molecular characteristics for gastric cancer has enabled the molecular classification of gastric cancer, the diagnosis of gastric cancer, the prediction of prognosis, the recognition of gastric cancer driver genes, and the discovery of potential therapeutic targets. Not only have we deeper insights for the molecular diversity of gastric cancer, but we have also prospected both affirmative potentials and hurdles to molecular diagnostics. New paradigm of transdisciplinary team science, which is composed of innovative explorations and clinical investigations of oncologists, geneticists, pathologists, biologists, and bio-informaticians, is mandatory to recognize personalized target therapy. PMID:24156032

  15. Molecular Mechanisms Underlying the Antitumor Activity of 3-Aminopropanamide Irreversible Inhibitors of the Epidermal Growth Factor Receptor in Non–Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Elena Galvani

    2013-01-01

    Full Text Available Overcoming the emergence of acquired resistance to clinically approved epidermal growth factor receptor (EGFR inhibitors is a major challenge in the treatment of advanced non–small cell lung cancer (NSCLC. The aim of this study was to investigate the effects of a series of novel compounds affecting viability of NSCLC NCI-H1975 cells (carrying the EGFR T790M mutation. The inhibition of the autophosphorylation of EGFR occurred at nanomolar concentrations and both UPR1282 and UPR1268 caused a significant induction of apoptosis. Targeting of EGFR and downstream pathways was confirmed by a peptide substrate array, which highlighted the inhibition of other kinases involved in NSCLC cell aggressive behavior. Accordingly, the drugs inhibited migration (about 30% vs. control, which could be, in part, explained also by the increase of E-cadherin expression. Additionally, we observed a contraction of the volume of H1975 spheroids, associated with the reduction of the cancer stem–like cell hallmark CD133. The activity of UPR1282 was retained in H1975 xenograft models where it determined tumor shrinkage (P < .05 and resulted well tolerated compared to canertinib. Of note, the kinase activity profile of UPR1282 on xenograft tumor tissues showed overlapping results with respect to the activity in H1975 cells, unraveling the inhibition of kinases involved in pivotal proliferation and invasive signaling pathways. In conclusion, UPR1282 and UPR1268 are effective against various processes involved in malignancy transformation and progression and may be promising compounds for the future treatment of gefitinib-resistant NSCLCs.

  16. Thymic Output: Influence Factors and Molecular Mechanism

    Institute of Scientific and Technical Information of China (English)

    Rong Jin; Jun Zhang; Weifeng Chen

    2006-01-01

    Thymus is a primary lymphoid organ, able to generate mature T cells that eventually colonize secondary lymphoid organs, and is therefore essential for peripheral T cell renewal. Recent data showed that normal thymocyte export can be altered by several influence factors including several chemokines,sphingosinel-phosphate (S1P),transcription factors such as Foxjl, Kruppel-like transcription factor 2 (KLF2) and antigen stimulation, etc. In this review, we summarized the recent reports about study strategies, influence factors and possible molecular mechanisms in thymic output.

  17. Mechanisms Linking Obesity and Cancer

    OpenAIRE

    Louie, Sharon M.; Roberts, Lindsay S.; Daniel K Nomura

    2013-01-01

    The incidence of obesity in US adults has been steadily increasing over the past few decades. Many comorbidities associated with obesity have been well-established such as type 2 diabetes and cardiovascular diseases. However, more recently an epidemiological relationship between obesity and the prevalence of a variety of cancers has also been uncovered. The shift of the paradigm surrounding white adipose tissue function from purely an energy storage tissue, to one that has both endocrine and ...

  18. Breast cancer. From molecular biology to personified therapy

    Directory of Open Access Journals (Sweden)

    Bondarenko I.N.

    2016-03-01

    Full Text Available Advances in molecular biology had changed approaches to systemic treatment of breast cancer. Clinical decisions on the choice of optimal treatment regimens are performing on the basis of immunohistochemical and molecular genetic classifications. Their increasing uses have contributed changes of paradigm for cancer treatment - from the empirical to the individualized and personalized. The basis for such approaches is knowledge of molecular epidemiology, heterogeneity of expression of molecular subtypes, prognostic and predictive biomarkers of breast cancer. Breast cancer is a widely heterogeneous disease with 20 histological types, 8, molecular-genetic, 6 genomic subtypes, which are characterized by specific molecular and biochemical properties, different clinical course and different outcomes. Molecular genetic classification, created not on the basis of clinical, anatomical and morphological heterogeneity of tumor cells, and on the basis of their molecular-genetic heterogeneity is widely used in clinical practice. This allowed to separate the patients with breast cancer to molecular 4 subtypes - luminal A, luminal B, HER / 2 positive and triple-negative. The significant role of immunohistochemical tissue tumor markers, estrogen and progesterone receptors, HER / 2-neu, Ki-67, p53 for selection the optimal treatment strategy is analyzing in this review. To increase the effectiveness of breast cancer treatment is possible, using a differentiated and personalized approach based on new molecular genetic classification of breast cancer (gene profiling or to its analogue - expression classification of breast cancer, based on the principle of diversity of immunohistochemical tumor tissue. Personification of cancer treatment involves a therapy based on the study of individual characteristics of tissue is not only the primary tumor but also its metastases. Citation: Bondarenko IN, Elhajj Mohammad H, Prokhach AV, Zavizion VF, Chebanov KO. [Breast cancer

  19. Molecular mechanisms of glucocorticoid receptor signaling

    Directory of Open Access Journals (Sweden)

    Marta Labeur

    2010-10-01

    Full Text Available This review highlights the most recent findings on the molecular mechanisms of the glucocorticoid receptor (GR. Most effects of glucocorticoids are mediated by the intracellular GR which is present in almost every tissue and controls transcriptional activation via direct and indirect mechanisms. Nevertheless the glucocorticoid responses are tissue -and gene- specific. GR associates selectively with corticosteroid ligands produced in the adrenal gland in response to changes of humoral homeostasis. Ligand interaction with GR promotes either GR binding to genomic glucocorticoid response elements, in turn modulating gene transcription, or interaction of GR monomers with other transcription factors activated by other signalling pathways leading to transrepression. The GR regulates a broad spectrum of physiological functions, including cell differentiation, metabolism and inflammatory responses. Thus, disruption or dysregulation of GR function will result in severe impairments in the maintenance of homeostasis and the control of adaptation to stress.

  20. Statistical mechanics and dynamics of molecular fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Quack, M. (Goettingen Univ. (Germany, F.R.). Inst. fuer Physikalische Chemie)

    1981-05-11

    The foundations of the use of statistical-mechanical equations of motion, in particular the Pauli equation, for the description of intramolecular processes and molecular fragmentation are discussed briefly. Quantum-mechanical trajectories for model systems illustrate how the statistical behaviour may emerge from the dynamical equations of motion. Product state distributions resulting from the fragmentation of strongly coupled, metastable intermediates in chemical-activation experiments can be calculated by using restricted equipartition, which applies as the long-time limit of the Pauli equation. A simple Pauli-equation model is proposed to calculate lifetimes of metastable intermediates. The consequences of the finite rate of intramolecular relaxation processes for the specific rate constants for fragmentation and possible deviations from microcanonical equilibrium are explored.

  1. Statistical mechanics and dynamics of molecular fragmentation

    International Nuclear Information System (INIS)

    The foundations of the use of statistical-mechanical equations of motion, in particular the Pauli equation, for the description of intramolecular processes and molecular fragmentation are discussed briefly. Quantum-mechanical trajectories for model systems illustrate how the statistical behaviour may emerge from the dynamical equations of motion. Product state distributions resulting from the fragmentation of strongly coupled, metastable intermediates in chemical-activation experiments can be calculated by using restricted equipartition, which applies as the long-time limit of the Pauli equation. A simple Pauli-equation model is proposed to calculate lifetimes of metastable intermediates. The consequences of the finite rate of intramolecular relaxation processes for the specific rate constants for fragmentation and possible deviations from microcanonical equilibrium are explored. (author)

  2. [Molecular mechanisms regulating the activity of macrophages].

    Science.gov (United States)

    Onoprienko, L V

    2011-01-01

    This article reviews modern concepts of the most common types of macrophage activation: classical, alternative, and type II. Molecular mechanisms of induction and regulation of these three types of activation are discussed. Any population of macrophages was shown to change its properties depending on its microenvironment and concrete biological situation (the "functional plasticity of macrophages"). Many intermediate states of macrophages were described along with the most pronounced and well-known activation types (classical activation, alternative activation, and type II activation). These intermediate states are characterized by a variety of combinations of their biological properties, including elements of the three afore mentioned types of activation. Macrophage activity is regulated by a complex network of interrelated cascade mechanisms.

  3. Early-onset gastric cancers have a different molecular expression profile than conventional gastric cancers

    NARCIS (Netherlands)

    A.N.A. Milne; R. Carvalho; F.M. Morsink; A.R. Musler; W.W.J. de Leng; A. Ristimaki; G.J.A. Offerhaus

    2006-01-01

    Many studies examine the molecular genetics of gastric cancer, but few look at young patients in particular and there is no comparison of molecular expression between early-onset gastric cancer (<= 45 years old) and conventional gastric cancers. Expression of cycloxygenase-2 (COX-2) is elevated in g

  4. Molecular mechanism of size control in development and human diseases

    Institute of Scientific and Technical Information of China (English)

    Xiaolong Yang; Tian Xu

    2011-01-01

    How multicellular organisms control their size is a fundamental question that fascinated generations of biologists.In the past 10 years, tremendous progress has been made toward our understanding of the molecular mechanism underlying size control. Original studies from Drosophila showed that in addition to extrinsic nutritional and hormonal cues, intrinsic mechanisms also play important roles in the control of organ size during development. Several novel signaling pathways such as insulin and Hippo-LATS signaling pathways have been identified that control organ size by regulating cell size and/or cell number through modulation of cell growth, cell division, and cell death. Later studies using mammalian cell and mouse models also demonstrated that the signaling pathways identified in flies are also conserved in mammals. Significantly, recent studies showed that dysregulation of size control plays important roles in the development of many human diseases sucha as cancer,diabetes,and hypertrophy.

  5. The consensus molecular subtypes of colorectal cancer.

    Science.gov (United States)

    Guinney, Justin; Dienstmann, Rodrigo; Wang, Xin; de Reyniès, Aurélien; Schlicker, Andreas; Soneson, Charlotte; Marisa, Laetitia; Roepman, Paul; Nyamundanda, Gift; Angelino, Paolo; Bot, Brian M; Morris, Jeffrey S; Simon, Iris M; Gerster, Sarah; Fessler, Evelyn; De Sousa E Melo, Felipe; Missiaglia, Edoardo; Ramay, Hena; Barras, David; Homicsko, Krisztian; Maru, Dipen; Manyam, Ganiraju C; Broom, Bradley; Boige, Valerie; Perez-Villamil, Beatriz; Laderas, Ted; Salazar, Ramon; Gray, Joe W; Hanahan, Douglas; Tabernero, Josep; Bernards, Rene; Friend, Stephen H; Laurent-Puig, Pierre; Medema, Jan Paul; Sadanandam, Anguraj; Wessels, Lodewyk; Delorenzi, Mauro; Kopetz, Scott; Vermeulen, Louis; Tejpar, Sabine

    2015-11-01

    Colorectal cancer (CRC) is a frequently lethal disease with heterogeneous outcomes and drug responses. To resolve inconsistencies among the reported gene expression-based CRC classifications and facilitate clinical translation, we formed an international consortium dedicated to large-scale data sharing and analytics across expert groups. We show marked interconnectivity between six independent classification systems coalescing into four consensus molecular subtypes (CMSs) with distinguishing features: CMS1 (microsatellite instability immune, 14%), hypermutated, microsatellite unstable and strong immune activation; CMS2 (canonical, 37%), epithelial, marked WNT and MYC signaling activation; CMS3 (metabolic, 13%), epithelial and evident metabolic dysregulation; and CMS4 (mesenchymal, 23%), prominent transforming growth factor-β activation, stromal invasion and angiogenesis. Samples with mixed features (13%) possibly represent a transition phenotype or intratumoral heterogeneity. We consider the CMS groups the most robust classification system currently available for CRC-with clear biological interpretability-and the basis for future clinical stratification and subtype-based targeted interventions.

  6. Multifunctional nanomaterials for advanced molecular imaging and cancer therapy

    Science.gov (United States)

    Subramaniam, Prasad

    Nanotechnology offers tremendous potential for use in biomedical applications, including cancer and stem cell imaging, disease diagnosis and drug delivery. The development of nanosystems has aided in understanding the molecular mechanisms of many diseases and permitted the controlled nanoscale manipulation of biological phenomena. In recent years, many studies have focused on the use of several kinds of nanomaterials for cancer and stem cell imaging and also for the delivery of anticancer therapeutics to tumor cells. However, the proper diagnosis and treatment of aggressive tumors such as brain and breast cancer requires highly sensitive diagnostic agents, in addition to the ability to deliver multiple therapeutics using a single platform to the target cells. Addressing these challenges, novel multifunctional nanomaterial-based platforms that incorporate multiple therapeutic and diagnostic agents, with superior molecular imaging and targeting capabilities, has been presented in this work. The initial part of this work presents the development of novel nanomaterials with superior optical properties for efficiently delivering soluble cues such as small interfering RNA (siRNA) into brain cancer cells with minimal toxicity. Specifically, this section details the development of non-toxic quantums dots for the imaging and delivery of siRNA into brain cancer and mesenchymal stem cells, with the hope of using these quantum dots as multiplexed imaging and delivery vehicles. The use of these quantum dots could overcome the toxicity issues associated with the use of conventional quantum dots, enabled the imaging of brain cancer and stem cells with high efficiency and allowed for the delivery of siRNA to knockdown the target oncogene in brain cancer cells. The latter part of this thesis details the development of nanomaterial-based drug delivery platforms for the co-delivery of multiple anticancer drugs to brain tumor cells. In particular, this part of the thesis focuses on

  7. Hormonal and molecular aspects of endometrioid endometrial cancer

    NARCIS (Netherlands)

    Jongen, Vincentius Hubertus Willibrordus Maria

    2008-01-01

    This thesis concerns the expression and prognostic value of various hormones and molecular markers playing a role n endometrioid endometrial cancer. Especially we were interested in the enzyme aromatase, its expression and (prognostic) role in endometrioid endometrial cancer. Endometrial cancer is t

  8. Molecular Markers with Predictive and Prognostic Relevance in Lung Cancer

    Directory of Open Access Journals (Sweden)

    Alphy Rose-James

    2012-01-01

    Full Text Available Lung cancer accounts for the majority of cancer-related deaths worldwide of which non-small-cell lung carcinoma alone takes a toll of around 85%. Platinum-based therapy is the stronghold for lung cancer at present. The discovery of various molecular alterations that underlie lung cancer has contributed to the development of specifically targeted therapies employing specific mutation inhibitors. Targeted chemotherapy based on molecular profiling has shown great promise in lung cancer treatment. Various molecular markers with predictive and prognostic significance in lung cancer have evolved as a result of advanced research. Testing of EGFR and Kras mutations is now a common practice among community oncologists, and more recently, ALK rearrangements have been added to this group. This paper discusses various predictive and prognostic markers that are being investigated and have shown significant relevance which can be exploited for targeted treatment in lung cancer.

  9. Molecular inhibitory mechanism of tricin on tyrosinase

    Science.gov (United States)

    Mu, Yan; Li, Lin; Hu, Song-Qing

    2013-04-01

    Tricin was evaluated as a type of tyrosinase inhibitor with good efficacy compared to arbutin. Tricin functioned as a non-competitive inhibitor of tyrosinase, with an equilibrium constant of 2.30 mmol/L. The molecular mechanisms underlying the inhibition of tyrosinase by tricin were investigated by means of circular dichroism spectra, fluorescence quenching and molecular docking. These assays demonstrated that the interactions between tricin and tyrosinase did not change the secondary structure. The interaction of tricin with residues in the hydrophobic pocket of tyrosinase was revealed by fluorescence quenching; the complex was stabilized by hydrophobic associations and hydrogen bonding (with residues Asn80 and Arg267). Docking results implied that the possible inhibitory mechanisms may be attributed to the stereospecific blockade effects of tricin on substrates or products and flexible conformation alterations in the tyrosinase active center caused by weak interactions between tyrosinase and tricin. The application of this type of flavonoid as a tyrosinase inhibitor will lead to significant advances in the field of depigmentation.

  10. Mechanisms of Base Substitution Mutagenesis in Cancer Genomes

    Directory of Open Access Journals (Sweden)

    Albino Bacolla

    2014-03-01

    Full Text Available Cancer genome sequence data provide an invaluable resource for inferring the key mechanisms by which mutations arise in cancer cells, favoring their survival, proliferation and invasiveness. Here we examine recent advances in understanding the molecular mechanisms responsible for the predominant type of genetic alteration found in cancer cells, somatic single base substitutions (SBSs. Cytosine methylation, demethylation and deamination, charge transfer reactions in DNA, DNA replication timing, chromatin status and altered DNA proofreading activities are all now known to contribute to the mechanisms leading to base substitution mutagenesis. We review current hypotheses as to the major processes that give rise to SBSs and evaluate their relative relevance in the light of knowledge acquired from cancer genome sequencing projects and the study of base modifications, DNA repair and lesion bypass. Although gene expression data on APOBEC3B enzymes provide support for a role in cancer mutagenesis through U:G mismatch intermediates, the enzyme preference for single-stranded DNA may limit its activity genome-wide. For SBSs at both CG:CG and YC:GR sites, we outline evidence for a prominent role of damage by charge transfer reactions that follow interactions of the DNA with reactive oxygen species (ROS and other endogenous or exogenous electron-abstracting molecules.

  11. Molecular Pathways: Estrogen Pathway in Colorectal Cancer

    Science.gov (United States)

    Barzi, Afsaneh; Lenz, Annika Medea; Labonte, Melissa J.; Lenz, Heinz-Josef

    2013-01-01

    Worldwide colorectal cancer (CRC) has a higher incidence rate in men than in women, suggesting a protective role for sex hormones in the development of the disease. Preclinical data supports a role for estrogen and its receptors in the initiation and progression of CRC and establishes that protective effects of estrogen are exerted through ERβ. Hormone replacement therapy (HRT) in postmenopausal women as well as consumption of soy reduces the incidence of CRC. In the Women’s Health Initiative (WHI) trial use of HRT in postmenopausal women reduced the risk of colon cancer by 56% (95% CI, 0.38 to 0.81; P=0.003). A recent meta-analysis showed that in females, consumption of soy reduced the risk of colon cancer by 21% (95% CI, 0.03 to 0.35; P=0.026). In this review, utilizing the preclinical data, we translate the findings in the clinical trials and observational studies to define the role of estrogen in the prevention of CRC. We hypothesize that sometime during the tumorigenesis process ERβ expression in colonocytes is lost and the estrogen ligand, HRT or soy products, exerts its effects through preventing this loss. Thus in the adenoma to carcinoma continuum, timing of HRT is a significant determinant of the observed benefit from this intervention. We further argue that the protective effects of estrogen are limited to certain molecular subtypes. Successful development of estrogen modulators for prevention of CRC depends on identification of susceptible CRC population(s). Thus research to better understand the estrogen pathway is fundamental for clinical delivery of these agents. PMID:23965904

  12. Molecular Mechanisms Regulating Macrophage Response to Hypoxia

    Directory of Open Access Journals (Sweden)

    Michal Amit Rahat

    2011-09-01

    Full Text Available Monocytes and Macrophages (Mo/Mϕ exhibit great plasticity, as they can shift between different modes of activation and, driven by their immediate microenvironment, perform divergent functions. These include, among others, patrolling their surroundings and maintaining homeostasis (resident Mo/Mϕ, combating invading pathogens and tumor cells (classically activated or M1 Mo/Mϕ, orchestrating wound healing (alternatively activated or M2 Mo/Mϕ, and restoring homeostasis after an inflammatory response (resolution Mϕ. Hypoxia is an important factor in the Mϕ microenvironment, is prevalent in many physiological and pathological conditions, and is interdependent with the inflammatory response. Although Mo/Mϕ have been studied in hypoxia, the mechanisms by which hypoxia influences the different modes of their activation, and how it regulates the shift between them, remain unclear. Here we review the current knowledge about the molecular mechanisms that mediate this hypoxic regulation of Mϕ activation. Much is known about the hypoxic transcriptional regulatory network, which includes the master regulators HIF-1 and NF-κB, as well as other transcription factors (e.g. AP-1, Erg-1, but we also highlight the role of post-transcriptional and post-translational mechanisms. These mechanisms mediate hypoxic induction of Mϕ pro-angiogenic mediators, suppress M1 Mϕ by post-transcriptionally inhibiting pro-inflammatory mediators, and help shift the classically activated Mϕ into an activation state which approximate the alternatively activated or resolution Mϕ.

  13. Cellular and molecular mechanisms of muscle atrophy

    Directory of Open Access Journals (Sweden)

    Paolo Bonaldo

    2013-01-01

    Full Text Available Skeletal muscle is a plastic organ that is maintained by multiple pathways regulating cell and protein turnover. During muscle atrophy, proteolytic systems are activated, and contractile proteins and organelles are removed, resulting in the shrinkage of muscle fibers. Excessive loss of muscle mass is associated with poor prognosis in several diseases, including myopathies and muscular dystrophies, as well as in systemic disorders such as cancer, diabetes, sepsis and heart failure. Muscle loss also occurs during aging. In this paper, we review the key mechanisms that regulate the turnover of contractile proteins and organelles in muscle tissue, and discuss how impairments in these mechanisms can contribute to muscle atrophy. We also discuss how protein synthesis and degradation are coordinately regulated by signaling pathways that are influenced by mechanical stress, physical activity, and the availability of nutrients and growth factors. Understanding how these pathways regulate muscle mass will provide new therapeutic targets for the prevention and treatment of muscle atrophy in metabolic and neuromuscular diseases.

  14. Animal models and therapeutic molecular targets of cancer: utility and limitations

    Directory of Open Access Journals (Sweden)

    Cekanova M

    2014-10-01

    Full Text Available Maria Cekanova, Kusum Rathore Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN, USA Abstract: Cancer is the term used to describe over 100 diseases that share several common hallmarks. Despite prevention, early detection, and novel therapies, cancer is still the second leading cause of death in the USA. Successful bench-to-bedside translation of basic scientific findings about cancer into therapeutic interventions for patients depends on the selection of appropriate animal experimental models. Cancer research uses animal and human cancer cell lines in vitro to study biochemical pathways in these cancer cells. In this review, we summarize the important animal models of cancer with focus on their advantages and limitations. Mouse cancer models are well known, and are frequently used for cancer research. Rodent models have revolutionized our ability to study gene and protein functions in vivo and to better understand their molecular pathways and mechanisms. Xenograft and chemically or genetically induced mouse cancers are the most commonly used rodent cancer models. Companion animals with spontaneous neoplasms are still an underexploited tool for making rapid advances in human and veterinary cancer therapies by testing new drugs and delivery systems that have shown promise in vitro and in vivo in mouse models. Companion animals have a relatively high incidence of cancers, with biological behavior, response to therapy, and response to cytotoxic agents similar to those in humans. Shorter overall lifespan and more rapid disease progression are factors contributing to the advantages of a companion animal model. In addition, the current focus is on discovering molecular targets for new therapeutic drugs to improve survival and quality of life in cancer patients. Keywords: mouse cancer model, companion animal cancer model, dogs, cats, molecular targets

  15. Molecular aspects of carcinogenesis in pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Alexandros Koliopanos; Constantinos Avgerinos; Constantina Paraskeva; Zisis Touloumis; Dionisisa Kelgiorgi; Christos Dervenis

    2008-01-01

    BACKGROUND: Pancreatic cancer (PCa) is one of the most aggressive human solid tumors, with rapid growth and metastatic spread as well as resistance to chemotherapeutic drugs, leading rapidly to virtually incurable disease. Over the last 20 years, however, signiifcant advances have been made in our understanding of the molecular biology of PCa, with a focus on the cytogenetic abnormalities in PCa cell growth and differentiation. DATA SOURCES: A MEDLINE search and manual cross-referencing were utilized to identify published data for PCa molecular biology studies between 1986 and 2008, with emphasis on genetic alterations and developmental oncology. RESULTS: Activation of oncogenes, deregulation of tumor suppressor and genome maintenance genes, upregulation of growth factors/growth factor receptor signaling cascade systems, and alterations in cytokine expression, have been reported to play important roles in the process of pancreatic carcinogenesis. Alterations in the K-ras proto-oncogene and the p16INK4a, p53, FHIT, and DPC4 tumor suppressor genes occur in a high percentage of tumors. Furthermore, a variety of growth factors are expressed at increased levels. In addition, PCa often exhibits alterations in growth inhibitory pathways and evades apoptosis through p53 mutations and aberrant expression of apoptosis-regulating genes, such as members of the Bcl family. Additional pathways in the development of an aggressive phenotype, local inifltration and metastasis are still under ongoing genetic research. The present paper reviews recent studies on the pathogenesis of PCa, and includes a brief reference to alterations reported for other types of pancreatic tumor. CONCLUSIONS: Advances in molecular genetics and biology have improved our perception of the pathogenesis of PCa. However, further studies are needed to better understand the fundamental changes that occur in PCa, thus leading to better diagnostic and therapeutic management.

  16. Screened Electrostatic Interactions in Molecular Mechanics.

    Science.gov (United States)

    Wang, Bo; Truhlar, Donald G

    2014-10-14

    In a typical application of molecular mechanics (MM), the electrostatic interactions are calculated from parametrized partial atomic charges treated as point charges interacting by radial Coulomb potentials. This does not usually yield accurate electrostatic interactions at van der Waals distances, but this is compensated by additional parametrized terms, for example Lennard-Jones potentials. In the present work, we present a scheme involving radial screened Coulomb potentials that reproduces the accurate electrostatics much more accurately. The screening accounts for charge penetration of one subsystem's charge cloud into that of another subsystem, and it is incorporated into the interaction potential in a way similar to what we proposed in a previous article (J. Chem. Theory Comput. 2010, 6, 3330) for combined quantum mechanical and molecular mechanical (QM/MM) simulations, but the screening parameters are reoptimized for MM. The optimization is carried out with electrostatic-potential-fitted partial atomic charges, but the optimized parameters should be useful with any realistic charge model. In the model we employ, the charge density of an atom is approximated as the sum of a point charge representing the nucleus and inner electrons and a smeared charge representing the outermost electrons; in particular, for all atoms except hydrogens, the smeared charge represents the two outermost electrons in the present model. We find that the charge penetration effect can cause very significant deviations from the popular point-charge model, and by comparison to electrostatic interactions calculated by symmetry-adapted perturbation theory, we find that the present results are considerably more accurate than point-charge electrostatic interactions. The mean unsigned error in electrostatics for a large and diverse data set (192 interaction energies) decreases from 9.2 to 3.3 kcal/mol, and the error in the electrostatics for 10 water dimers decreases from 1.7 to 0.5 kcal

  17. Molecular mechanisms of HIV-1 associated neurodegeneration

    Indian Academy of Sciences (India)

    Hakan Ozdener

    2005-06-01

    Since identification of the human immunodeficiency virus-1 (HIV-1), numerous studies suggest a link between neurological impairments, in particular dementia, with acquired immunodeficiency syndrome (AIDS) with alarming occurrence worldwide. Approximately, 60% of HIV-infected people show some form of neurological impairment, and neuropathological changes are found in 90% of autopsied cases. Approximately 30% of untreated HIV-infected persons may develop dementia. The mechanisms behind these pathological changes are still not understood. Mounting data obtained by in vivo and in vitro experiments suggest that neuronal apoptosis is a major feature of HIV associated dementia (HAD), which can occur in the absence of direct infection of neurons. The major pathway of neuronal apoptosis occurs indirectly through release of neurotoxins by activated cells in the central nervous system (CNS) involving the induction of excitotoxicity and oxidative stress. In addition a direct mechanism induced by viral proteins in the pathogenesis of HAD may also play a role. This review focuses on the molecular mechanisms of HIV-associated dementia and possible therapeutic strategies.

  18. Expression, clinical significance and mechanism of Slit2 in papillary thyroid cancer.

    Science.gov (United States)

    Shi, Rong-Liang; Qu, Ning; Liao, Tian; Wang, Yu-Long; Wang, Yu; Sun, Guo-Hua; Ji, Qing-Hai

    2016-05-01

    Thyroid cancer is a common endocrine malignancy. The last decade has seen exciting progress in understanding thyroid cancer molecular pathogenesis. Several major signaling pathways and related molecular derangements have been elucidated, which represent novel diagnostic and prognostic molecular markers for thyroid cancer. Based on the molecular biology of thyroid cancer, a series of therapeutic targets have been developed, which provide unprecedented opportunities. Thus, histological characterization of subgroups of patients and the correct molecular characterization of patients are thought to be key aspects for future clinical management of these patients. In the present study, we identified Slit2 as a prognostic marker for thyroid cancer oncogenesis and recurrence. Mechanistically, Slit2 regulated Warburg effect in thyroid cancer cells through regulation of HIF1α and HIF1α transcriptional activity. Taken together, our present data uncovered Slit2 as a novel predictive marker for thyroid cancer. The mechanism study indicated that Slit2 regulated the Warburg effect. Additional study on the function of Slit2 in thyroid cancer is required to provide new insights into the potential mechanisms of oncogenesis and recurrence potential of thyroid cancer.

  19. Molecular Dimensions of Gastric Cancer: Translational and Clinical Perspectives.

    Science.gov (United States)

    Choi, Yoon Young; Noh, Sung Hoon; Cheong, Jae-Ho

    2016-01-01

    Gastric cancer is a global health burden and has the highest incidence in East Asia. This disease is complex in nature because it arises from multiple interactions of genetic, local environmental, and host factors, resulting in biological heterogeneity. This genetic intricacy converges on molecular characteristics reflecting the pathophysiology, tumor biology, and clinical outcome. Therefore, understanding the molecular characteristics at a genomic level is pivotal to improving the clinical care of patients with gastric cancer. A recent landmark study, The Cancer Genome Atlas (TCGA) project, showed the molecular landscape of gastric cancer through a comprehensive molecular evaluation of 295 primary gastric cancers. The proposed molecular classification divided gastric cancer into four subtypes: Epstein-Barr virus-positive, microsatellite unstable, genomic stable, and chromosomal instability. This information will be taken into account in future clinical trials and will be translated into clinical therapeutic decisions. To fully realize the clinical benefit, many challenges must be overcome. Rapid growth of high-throughput biology and functional validation of molecular targets will further deepen our knowledge of molecular dimensions of this cancer, allowing for personalized precision medicine. PMID:26498010

  20. Molecular Mechanisms of DNA Replication Checkpoint Activation

    Directory of Open Access Journals (Sweden)

    Bénédicte Recolin

    2014-03-01

    Full Text Available The major challenge of the cell cycle is to deliver an intact, and fully duplicated, genetic material to the daughter cells. To this end, progression of DNA synthesis is monitored by a feedback mechanism known as replication checkpoint that is untimely linked to DNA replication. This signaling pathway ensures coordination of DNA synthesis with cell cycle progression. Failure to activate this checkpoint in response to perturbation of DNA synthesis (replication stress results in forced cell division leading to chromosome fragmentation, aneuploidy, and genomic instability. In this review, we will describe current knowledge of the molecular determinants of the DNA replication checkpoint in eukaryotic cells and discuss a model of activation of this signaling pathway crucial for maintenance of genomic stability.

  1. Molecular mechanism of TNF signaling and beyond

    Institute of Scientific and Technical Information of China (English)

    Zheng-gang LIU

    2005-01-01

    Tumor necrosis factor (TNF) is a proinflammatory cytokine that plays a critical role in diverse cellular events,including cell proliferation, differentiation and apoptosis. TNF is also involved in many types of diseases. In recent years, the molecular mechanisms of TNF functions have been intensively investigated. Studies from many laboratories have demonstrated that the TNF-mediated diverse biological responses are achieved through activating multiple signaling pathways. Especially the activation of transcription factors NF-κB and AP-1 plays a critical role in mediating these cellular responses. Several proteins, including FADD, the death domain kinase RIP and the TNF receptor associated factor TRAF2 have been identified as the key effectors of TNF signaling. Recently, we found that the effector molecules of TNF signaling, such as RIP and TRAF2, are also involved in other cellular responses. These finding suggests that RIP and TRAF2 serve a broader role than as just an effector of TNF signaling.

  2. Molecular mechanisms involved in intestinal iron absorption

    Institute of Scientific and Technical Information of China (English)

    Paul Sharp; Surjit Kaila Srai

    2007-01-01

    Iron is an essential trace metal in the human diet due to its obligate role in a number of metabolic processes.In the diet, iron is present in a number of different forms, generally described as haem (from haemoglobin and myoglobin in animal tissue) and non-haem iron (including ferric oxides and salts, ferritin and lactoferrin).This review describes the molecular mechanisms that co-ordinate the absorption of iron from the diet and its release into the circulation. While many components of the iron transport pathway have been elucidated, a number of key issues still remain to be resolved. Future work in this area will provide a clearer picture regarding the transcellular flux of iron and its regulation by dietary and humoral factors.

  3. Drug-DNA intercalation: from discovery to the molecular mechanism.

    Science.gov (United States)

    Mukherjee, Arnab; Sasikala, Wilbee D

    2013-01-01

    The ability of small molecules to perturb the natural structure and dynamics of nucleic acids is intriguing and has potential applications in cancer therapeutics. Intercalation is a special binding mode where the planar aromatic moiety of a small molecule is inserted between a pair of base pairs, causing structural changes in the DNA and leading to its functional arrest. Enormous progress has been made to understand the nature of the intercalation process since its idealistic conception five decades ago. However, the biological functions were detected even earlier. In this review, we focus mainly on the acridine and anthracycline types of drugs and provide a brief overview of the development in the field through various experimental methods that led to our present understanding of the subject. Subsequently, we discuss the molecular mechanism of the intercalation process, free-energy landscapes, and kinetics that was revealed recently through detailed and rigorous computational studies.

  4. Molecular Mechanisms of Insulin Resistance Development

    Directory of Open Access Journals (Sweden)

    Vsevolod Arsen'evich Tkachuk

    2014-05-01

    Full Text Available Insulin resistance (IR is a phenomenon associated with an impaired ability of insulin to stimulate glucose uptake by target cells and to reduce the blood glucose level. A response increase in insulin secretion by the pancreas and hyperinsulinemia are compensatory reactions of the body. The development of IR leads to the inability of target cells to respond to insulin that results in developing type 2 diabetes mellitus (T2DM and metabolic syndrome. For this reason, the metabolic syndrome is defined in practice as a combination of IR with one or more pathologies such as T2DM, arterial hypertension, dyslipidemia, abdominal obesity, non-alcoholic fatty liver disease, and some others. However, a combination of high blood glucose and insulin levels always serves as its physiological criterion.IR should be considered as a systemic failure of the endocrine regulation in the body. Physiological causes of IR are diverse. The main ones are nutritional overload and accumulation of certain lipids and their metabolites in cells, low physical activity, chronic inflammation and stress of various nature, including oxidative and endoplasmic reticulum stress (impairment of damaged protein degradation in the cell. Recent studies have demonstrated that these physiological mechanisms likely act through a single intracellular scenario. This is the impairment of signal transduction from the insulin receptor to its targets via the negative feedback mechanism in intracellular insulin-dependent signaling cascades.This review describes the physiological and intracellular mechanisms of insulin action and focuses on their abnormalities upon IR development. Finally, feasible trends in early molecular diagnosis and therapy of IR are discussed.

  5. Molecular Mechanisms of Pulmonary Vascular Remodeling in Pulmonary Arterial Hypertension

    Directory of Open Access Journals (Sweden)

    Jane A. Leopold

    2016-05-01

    Full Text Available Pulmonary arterial hypertension (PAH is a devastating disease that is precipitated by hypertrophic pulmonary vascular remodeling of distal arterioles to increase pulmonary artery pressure and pulmonary vascular resistance in the absence of left heart, lung parenchymal, or thromboembolic disease. Despite available medical therapy, pulmonary artery remodeling and its attendant hemodynamic consequences result in right ventricular dysfunction, failure, and early death. To limit morbidity and mortality, attention has focused on identifying the cellular and molecular mechanisms underlying aberrant pulmonary artery remodeling to identify pathways for intervention. While there is a well-recognized heritable genetic component to PAH, there is also evidence of other genetic perturbations, including pulmonary vascular cell DNA damage, activation of the DNA damage response, and variations in microRNA expression. These findings likely contribute, in part, to dysregulation of proliferation and apoptosis signaling pathways akin to what is observed in cancer; changes in cellular metabolism, metabolic flux, and mitochondrial function; and endothelial-to-mesenchymal transition as key signaling pathways that promote pulmonary vascular remodeling. This review will highlight recent advances in the field with an emphasis on the aforementioned molecular mechanisms as contributors to the pulmonary vascular disease pathophenotype.

  6. 益生菌抗结肠癌作用及分子机制研究进展%Research Progress of Probiotics in Colon Cancer Prevention and Its Molecular Mechanism

    Institute of Scientific and Technical Information of China (English)

    李冰; 单毓娟; 张兰威; 张英春; 陈镜羽

    2013-01-01

    Probiotics are usually live microorganisms which confer health benefits on host like improving intestinal flora balance. It can improve a number of physiological functions such as enhancing immunity, relieving hypersensitivity and inflammatory bowel disease, defencing infection, as well as anticancer, etc. This review summary the research progress of anti-colon-cancer effectiveness of probiotics, its fermentation broth, its bacteria composition and metabolic compositions firstly. Then the molecular mechanisms of its anti-colon carcinoma properties are introduced. Its molecular mechanisms mainly includes: immune-modulatory properties and anti-inflammatory, inhibiting proliferation and promoting apoptosis, producing beneficial metabolites, inhibiting carcinogens-activated enzyme and an-ti-genotoxic activity. Finally, the applications of probiotics in clinic are presented. The results show that probiotics not only play a protective role in the development of colon cancer, but also greatly improve the gut symptoms of patients with carcinoma after colostomy. At present, separation of active probiotic bacteria ingredients and its function research has become a research focus. These will provide the novel strategies and idea for exploring , exploiting and applying the products of probiotics in future.%益生菌是指一类通过改善肠内菌群平衡,对宿主起到有益作用的活性微生物,具有提高免疫力、抗过敏、缓解炎性肠道疾病、抗感染、抗癌等生物学功能.本文首先阐述益生菌、益生菌发酵液、其菌体成分、代谢成分抗结肠癌作用的研究进展;随后阐述其抗结肠癌的分子机制,主要包括;免疫调节和抗炎症作用,抑制细胞增殖和促进细胞凋亡,产生有益的代谢物和抑制致癌物活化酶与遗传解毒;最后介绍益生菌在临床医学研究中的应用情况,益生菌不仅可以在结肠癌发生过程中起到一定的保护作用,且能够很好的改善结肠

  7. [Molecular biological predictors for kidney cancer].

    Science.gov (United States)

    Vtorushin, S V; Tarakanova, V O; Zavyalova, M V

    2016-01-01

    The paper considers the data available in the modern literature on studies of potential molecular predictors for renal cell carcinoma (RCC). Investigations of cell death markers, namely; Bcl-2 as an inhibitor of apoptosis, are of interest. Its high expression correlates with a more favorable prognosis. Inactivation of Berclin 1 that is an authophagy indicator in intact tissues gives rise to t high risk for tumorigenesis. At the same time, high Beclin 1 expression in the tissue of the tumor itself results in the lower efficiency of performed chemotherapy. Excess annexin A2 in the tumor promotes the growth and invasion of cancer cells. Patients with tumor over-expression of SAM68 protein involved in cell proliferation have a lower overall survival rate. The lifespan of patients without distinct metastases survive significantly longer in the overexpression of epithelial cell adhesion molecule (EpCAM). High PD-L1 protein expression on the cell membrane is considered to be a potential marker of effective immunotherapy for RCC. PMID:27077146

  8. Molecular biology of breast cancer metastasis Molecular expression of vascular markers by aggressive breast cancer cells

    International Nuclear Information System (INIS)

    During embryogenesis, the formation of primary vascular networks occurs via the processes of vasculogenesis and angiogenesis. In uveal melanoma, vasculogenic mimicry describes the 'embryonic-like' ability of aggressive, but not nonaggressive, tumor cells to form networks surrounding spheroids of tumor cells in three-dimensional culture; these recapitulate the patterned networks seen in patients' aggressive tumors and correlates with poor prognosis. The molecular profile of these aggressive tumor cells suggests that they have a deregulated genotype, capable of expressing vascular phenotypes. Similarly, the embryonic-like phenotype expressed by the aggressive human breast cancer cells is associated with their ability to express a variety of vascular markers. These studies may offer new insights for consideration in breast cancer diagnosis and therapeutic intervention strategies

  9. The molecular mechanisms of hazardous metals for carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    ChenJK; LeiYX

    2002-01-01

    The available experimental and epidemiological data have shown that nickel (Ni) and cadmium (Dd) and their compounds are carcinogenic to experimental animals and human.These two metals have been classified as human carcinogens bythe International Agency for Research on Cancer (IARC).However,Their underlying molecular mechanisms remain unknown.The objective of this research was to investigate the molecular mechanisms responsible for Ni and Cd carcinogenesis through epidemiological study in human exposure,transformation expreiments in human epithelial cells (16HBE) and BALB/c-3T3 cell lines in vitro,DNA damage detections (comet,DNA-protein crosslinks) as well as telomerase activity and apoptosis assay,and analysis of oncogens,tumor suppressor genes and their mutation (including genomic instability,k-ras,p15,p16,p53,FHIT) in transformed cell lines or tumor cells/tissue.Furthermore,we also detected and analyses the methylation,related novel genes and encoded protein in Cd transformed cells.The results and conclusion are as follows:(1)There is significant relationship between some hazardous metals and lung cancer (OR=8.76),especially for nickel(OR=11.25).(2)Ni and Cd and their compounds could induce malignant transformation in mammalian cell lines and human epithelial cells,and induce tumorigenesis in nude mice.(3)There is obvious DNA damage during cell transformation and tumorigenesis induced by Ni.(4) Significant genomic instability has been shown during cell transformation and tumorigenesis induced by Ni.(5)Detection of k-ras,p15,p16 genes in point mutation have demonstrated no changes during cell transformation and tumorigenesis induced by hazardous medals,suggesting that gene mutation is not the main way to metal carcinogenesis.(6)There are some aberrant DNA methylation in Cdtransformed cell lines.(7)We found two novel Cd-responsive proto-oncogenes and their encoded proteins in Cd-transformed cell lines.

  10. Quantum Interactomics and Cancer Molecular Mechanisms

    OpenAIRE

    Baianu, Dr. I.C.

    1987-01-01

    Single cell interactomics in simpler organisms, as well as somatic cell interactomics in multicellular organisms, involve biomolecular interactions in complex signalling pathways that were recently represented in modular terms by quantum automata with ‘reversible behavior’ representing normal cell cycling and division. Other implications of such quantum automata, modular modeling of signaling pathways and cell differentiation during development are in the fields of neural plasticity and brain...

  11. Molecular mechanisms in cancer induction and prevention.

    OpenAIRE

    Borek, C

    1993-01-01

    Chemical and physical carcinogens, present in our environment and encountered in a variety of occupations, produce damage to DNA. X-rays produced direct ionizations and indirect hydroxyl radical attack. UV light in the short wavelength is specifically absorbed by unsaturated bonds in DNA, RNA, and proteins. There are a number of genetic sites that are specifically affected by environmental agents, and an increased sensitivity is found in certain genetic diseases. The development of a fully ma...

  12. Applications of molecular MRI and optical imaging in cancer

    OpenAIRE

    Penet, Marie-France; Mikhaylova, Maria; Li, Cong; Krishnamachary, Balaji; Glunde, Kristine; Pathak, Arvind P.; Bhujwalla, Zaver M.

    2010-01-01

    Some of the most exciting advances in molecular-functional imaging of cancer are occurring at the interface between chemistry and imaging. Several of these advances have occurred through the development of novel imaging probes that report on molecular pathways, the tumor micro-environment and the response of tumors to treatment; as well as through novel image-guided platforms such as nanoparticles and nanovesicles that deliver therapeutic agents against specific targets and pathways. Cancer c...

  13. The Utility of Molecular Imaging in Prostate Cancer.

    Science.gov (United States)

    Leiblich, Aaron; Stevens, Daniel; Sooriakumaran, Prasanna

    2016-03-01

    Prostate cancer is the commonest solid-organ cancer diagnosed in males and represents an important source of morbidity and mortality worldwide. Imaging plays a crucial role in diagnosing prostate cancer and informs the ongoing management of the disease at all stages. Several novel molecular imaging technologies have been developed recently that have the potential to revolutionise disease diagnosis and the surveillance of patients living with prostate cancer. These innovations include hyperpolarised MRI, choline PET/CT and PSMA PET/CT. The major utility of choline and PSMA PET/CT currently lies in their sensitivity for detecting early recurrence after radical treatment for prostate cancer and identifying discrete lesions that may be amenable to salvage therapy. Molecular imaging is likely to play a future role in characterising genetic and biochemical signatures in individual tumours, which may be of particular significance as cancer therapies move into an era of precision medicine. PMID:26894753

  14. Molecular and cellular mechanisms of adipogenesis

    Directory of Open Access Journals (Sweden)

    Aleksander Dmitrievich Egorov

    2015-03-01

    Full Text Available The main components of metabolic syndrome include insulin resistance, hypertriglyceridemia and arterial hypertension. Obesity is the cause of metabolic syndrome, mainly as a consequence of the endocrine function of adipose tissue. The volume of adipose tissue depends on the size of individual adipocytes and on their number. The number of adipocytes increases as a result of enhanced adipocyte differentiation. The transcriptional cascade that regulates this differentiation has been well studied. The major adipogenic transcription factor peroxisome proliferator-activated receptor gamma is a ligand-activated nuclear receptor with essential roles in adipogenesis. Its ligands are used to treat metabolic syndrome and type 2 diabetes mellitus. The present article describes the basic molecular and cellular mechanisms of adipogenesis and discusses the impact of insulin, glucocorticoids, cyclic adenosine monophosphate-activating agents, nuclear receptors and transcription factors on the process of adipogenesis. New regulatory regions of the genome that are capable of binding multiple transcription factors are described, and the most promising drug targets for the treatment of metabolic syndrome and obesity, including the homeodomain proteins Pbx1 and Prep1, are discussed.

  15. Molecular and genetic mechanisms of environmental mutagens

    International Nuclear Information System (INIS)

    This program is primarily concerned with elucidation of the nature of DNA lesions produced by environmental and energy related mutagens, their mechanisms of action, and their repair. The main focus is on actions of chemical mutagens and electromagnetic radiations. Synergistic interactions between mutagens and the mutational processes that lead to synergism are being investigated. Mutagens are chosen for study on the basis of their potential for analysis of mutation (as genetic probes), for development of procedures for reducing mutational damage, for their potential importance to risk assessment, and for development of improved mutagen testing systems. Bacterial cells are used because of the rapidity and clarity of scientific results that can be obtained, the detailed genetic maps, and the many well-defined mutand strains available. The conventional tools of microbial and molecular genetics are used, along with intercomparison of genetically related strains. Advantage is taken of tcollective dose commitment will result in more attention being paid to potential releases of radionuclides at relatively short times after disposal

  16. Molecular Mechanism and Potential Targets for Blocking HPV-Induced Lesion Development

    Directory of Open Access Journals (Sweden)

    E. Guzmán-Olea

    2012-01-01

    Full Text Available Persistent infection with high-risk HPV is the etiologic agent associated with the development of cervical cancer (CC development. However, environmental, social, epidemiological, genetic, and host factors may have a joint influence on the risk of disease progression. Cervical lesions caused by HPV infection can be removed naturally by the host immune response and only a small percentage may progress to cancer; thus, the immune response is essential for the control of precursor lesions and CC. We present a review of recent research on the molecular mechanisms that allow HPV-infected cells to evade immune surveillance and potential targets of molecular therapy to inhibit tumor immune escape.

  17. Molecular Mechanism and Potential Targets for Blocking HPV-Induced Lesion Development.

    Science.gov (United States)

    Guzmán-Olea, E; Bermúdez-Morales, V H; Peralta-Zaragoza, O; Torres-Poveda, K; Madrid-Marina, V

    2012-01-01

    Persistent infection with high-risk HPV is the etiologic agent associated with the development of cervical cancer (CC) development. However, environmental, social, epidemiological, genetic, and host factors may have a joint influence on the risk of disease progression. Cervical lesions caused by HPV infection can be removed naturally by the host immune response and only a small percentage may progress to cancer; thus, the immune response is essential for the control of precursor lesions and CC. We present a review of recent research on the molecular mechanisms that allow HPV-infected cells to evade immune surveillance and potential targets of molecular therapy to inhibit tumor immune escape. PMID:22220169

  18. Mechanics at the molecular scale: Insight into the physical mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Neucheva, Olga A.; Temirov, Ruslan; Tautz, Stefan [Institut fuer Bio- und Nanosysteme (IBN-3) and JARA - Fundamental of Future Information Technology, Forschungszentrum Juelich, 52425 Juelich (Germany)

    2010-07-01

    The manipulation of atoms and molecules is one of the problems under investigation in a surface science. The first successful attempt to transfer an atom from a surface with use of a scanning tunneling microscope has been realized by Eigler et al. An interest to understand the underlying physical mechanism from both experimental and theoretical points of view has led to investigations of many systems which can be used as atomic and molecular switches. In our work the behaviour of a single PTCDA molecule on Ag(111) has been investigated with a LT-STM. Two level fluctuations of the conductance of the junction have been observed within a narrow range of the tip heights and bias voltages. The bistability is related to reversible switching of one of the carboxylic oxygen atoms between the surface and the STM-tip. The current passing through the junction induces vibrations of the molecule leading to weakening and breaking of a chemical bond with the surface and establishing a new one with the tip and vice versa. The switching frequency strongly depends on the bias voltages and tip heights, following a non-linear dependence on the current.

  19. New generation of breast cancer clinical trials implementing molecular profiling

    Institute of Scientific and Technical Information of China (English)

    Dimitrios Zardavas; Martine Piccart-Gebhart

    2016-01-01

    The implementation of molecular profiling technologies in oncology deepens our knowledge for the molecular landscapes of cancer diagnoses, identifying aberrations that could be linked with specific therapeutic vulnerabilities. In particular, there is an increasing list of molecularly targeted anticancer agents undergoing clinical development that aim to block specific molecular aberrations. This leads to a paradigm shift, with an increasing list of specific aberrations dictating the treatment of patients with cancer. This paradigm shift impacts the field of clinical trials, since the classical approach of having clinico-pathological disease characteristics dictating the patients' enrolment in oncology trials shifts towards the implementation of molecular profiling as pre-screening step. In order to facilitate the successful clinical development of these new anticancer drugs within specific molecular niches of cancer diagnoses, there have been developed new, innovative trial designs that could be classified as follows: i) longitudinal cohort studies that implement (or not) "nested" downstream trials, 2) studies that assess the clinical utility of molecular profiling, 3) "master" protocol trials, iv) "basket" trials, v) trials following an adaptive design. In the present article, we review these innovative study designs, providing representative examples from each category and we discuss the challenges that still need to be addressed in this era of new generation oncology trials implementing molecular profiling. Emphasis is put on the field of breast cancer clinical trials.

  20. Molecular markers for detection, surveillance and prognostication of bladder cancer.

    NARCIS (Netherlands)

    Vrooman, O.P.; Witjes, J.A.

    2009-01-01

    Many markers for the detection of bladder cancers have been tested and almost all urinary markers reported are better than cytology with regard to sensitivity, but they score lower in specificity. Currently molecular and genetic changes play an important role in the discovery of new molecular marker

  1. Molecular imaging of HER2-positive breast cancer

    DEFF Research Database (Denmark)

    Capala, Jacek; Bouchelouche, Kirsten

    2010-01-01

    HER2 overexpression is correlated with aggressive tumor behavior and poor clinical outcome. Therefore, HER2 has become an important prognostic and predictive factor, as well as a target for molecular therapies. The article reviews recent advances in molecular imaging of HER2 that could facilitate...... individual approaches to targeted therapy of HER2-positive breast cancers....

  2. Survivin-T34A: molecular mechanism and therapeutic potential

    Directory of Open Access Journals (Sweden)

    Jonathan R Aspe

    2010-12-01

    Full Text Available Jonathan R Aspe, Nathan R WallCenter for Health Disparities Research and Molecular Medicine, Division of Biochemistry and Microbiology, Department of Basic Sciences, Loma Linda University, Loma Linda, CA, USAAbstract: The inhibitor of apoptosis protein survivin's threonine 34 to alanine (T34A mutation abolishes a phosphorylation site for p34(cdc2–cyclin B1, resulting in initiation of the mitochondrial apoptotic pathway in cancer cells; however, it has little known direct effects on normal cells. The possibility that targeting survivin in this way may provide a novel approach for selective cancer gene therapy has yet to be fully evaluated. Although a flurry of work was undertaken in the late 1990s and early 2000s, only minor advances on this mutant have recently taken place. We recently described that cells generated to express a stable form of the mutant protein released this survivin-T34A to the conditioned medium. When this conditioned medium was collected and deposited on naive tumor cells, conditioned medium T34A was as effective as some chemotherapeutics in the induction of tumor cell apoptosis, and when combined with other forms of genotoxic stressors potentiated their killing effects. We hope with this review to revitalize the T34A field, as there is still much that needs to be investigated. In addition to determining the therapeutic dose and the duration of drug therapy required at the disease site, a better understanding of other key factors is also important. These include knowledge of target cell populations, cell-surface receptors, changes that occur in the target tissue at the molecular and cellular level with progression of the disease, and the mechanism and site of therapeutic action.Keywords: survivin, T34A, apoptosis, proliferation, therapy

  3. Physiology and molecular mechanism of glucocorticoid action

    Directory of Open Access Journals (Sweden)

    Andrzej Nagalski

    2010-03-01

    Full Text Available Endogenous glucocorticoids (GCs are secreted into the systemic circulation from the adrenal cortex. This release is under the control of the circadian clock and can be enhanced at any time in response to a stressor. The levels of circulating GC are regulated systemically by the hypothalamo-pituitary-adrenal axis and locally by access to target cells and pre-receptor metabolism by 11β-hydroxysteroids dehydrogenase enzymes. GCs mediate their genomic action by binding to two different ligand-inducible transcription factors: high-affinity mineralocorticoid receptor (MR and 10-fold lower affinity glucocorticoid receptors (GRs. Responses to GCs vary among individuals, cells, and tissues. The diversity and specificity in the steroid hormone’s response in the cell is controlled at different levels, including receptor translocation, interaction with specific transcription factors and coregulators, and the regulation of receptor protein levels by microRNA. Moreover, multiple GR isoforms are generated from one single GR gene by alternative splicing and alternative translation initiation. These isoforms all have unique tissue distribution patterns and transcriptional regulatory profiles. Furthermore, each is subjected to various post-translational modifications that affect receptor function. Deciphering the molecular mechanisms of GC action is further complicated by the realization that GCs can induce rapid, non-genomic effects within the cytoplasm. A tight regulation of GC secretion and their cell-specific activity is essential for proper organism function. This is particularly seen under conditions of GC deficiency or excess, as in Addison’s disease and Cushing’s syndrome, respectively.

  4. Novel approaches for the molecular classification of prostate cancer

    Institute of Scientific and Technical Information of China (English)

    Robert H. Getzenberg

    2010-01-01

    @@ Among the urologic cancers, prostate cancer is by far the most common, and it appears to have the potential to affect almost all men throughout the world as they age. A number of studies have shown that many men with prostate cancer will not die from their disease, but rather with the disease but from other causes. These men have a form of prostate cancer that is de-scribed as "very low risk" and has often been called indolent. There are however a group of men that have a form of prostate cancer that is much more aggressive and life threatening. Unlike other cancer types, we have few tools to provide for the molecular classification of prostate cancer.

  5. 从肝郁角度探讨乳腺癌发病机理及中医药干预的分子机制%Investigation on Pathogenesis of Breast Cancer and TCM Drug Intervention Molecular Mechanism from View of Liver Depression

    Institute of Scientific and Technical Information of China (English)

    吕雨桐; 李杰

    2013-01-01

    情志不畅与乳腺癌的发生、发展、预后密切相关.文章对古代医家及现代学者就肝郁与乳腺癌的发生、发展及辨病施治等方面进行了系统梳理,对情志因素与乳腺癌的关系进行分析,并从调控免疫抑制细胞的角度探讨了中医药干预的分子机制.作者认为,在乳腺癌的发生发展及治疗中,肝郁是基本病机,疏肝健脾是基本法则,调控免疫抑制是中药分子机制.%Depressive disorder is associated with the incidence of breast cancer development and prognosis.This paper summarizes the view of the ancient physicians and modern scholars on the occurrence of liver depression and breast cancer development and disease differentiation therapy to analyze the relationship between emotional factors and breast cancer and explore the molecular mechanisms of TCM intervention from the immunosuppressive cells point of view.Liver depression is the basic pathogenesis and the regulation of immune suppression is the molecular mechanism of Chinese medicine in the incidence of breast cancer development with method of soothing liver and strengthening spleen.

  6. Molecular Concordance Between Primary Breast Cancer and Matched Metastases

    DEFF Research Database (Denmark)

    Krøigård, Anne Bruun; Larsen, Martin Jakob; Thomassen, Mads;

    2016-01-01

    . The purpose of this review is to illuminate the extent of cancer genome evolution through disease progression and the degree of molecular concordance between primary breast cancers and matched metastases. We present an overview of the most prominent studies investigating the expression of endocrine receptors......Clinical management of breast cancer is increasingly personalized and based on molecular profiling. Often, primary tumors are used as proxies for systemic disease at the time of recurrence. However, recent studies have revealed substantial discordances between primary tumors and metastases, both......, transcriptomics, and genome aberrations in primary tumors and metastases. In conclusion, biopsy of metastatic lesions at recurrence of breast cancer is encouraged to provide optimal treatment of the disease. Furthermore, molecular profiling of metastatic tissue provides invaluable mechanistic insight...

  7. Role of Hedgehog signaling pathway in invasion and metastasis of gastric cancer and relevant molecular mechanism%Hedgehog信号通路在胃癌侵袭转移中的作用及分子机制

    Institute of Scientific and Technical Information of China (English)

    郝亚琴; 欧阳小波; 代剑波; 王立

    2012-01-01

    Objective To investigate the roles of Hedgehog (Hh) signaling pathway and epithelial-mesenchymal transition (EMT) in invasion and metastasis of gastric cancer as well as the relevant molecular mechanism. Methods Human gastric carcinoma SGC-7901 cells were treated with cyclopamine, Snail siRNA, empty plasmid and cyclopamine + Snail siRNA for 48 h respectively, using those in routine culture as control. The cells in various groups were determined for transcription levels of Glil, Snail and E-cadherin mRNAs by RT-PCR, for invasion ability by Transwell test, and for effect on adhesion ability to foreign matter by adhesion test on Marigel glue. Results Compared with those in control group, the transcription level of Glil mRNA in cyclopamine and cyclopamine + Snail siRNA groups decreased significantly (P < 0. 05); however, the transcription levels of Snail mRNA in cyclopamine, Snail siRNA and cyclopamine + Snail siRNA groups decreased significantly, while that of E-cadherin mRNA increased significantly (P < 0. 05). Both the invasion abilities and adhesion abilities to foreign matters of cells in cyclopamine, Snail siRNA and cyclopamine + Snail siRNA groups decreased significantly as compared with those in control group (P < 0. 05). Conclusion Hh signaling pathway may be involved in regulation of Snail by Glil to low the expression of E-cadherin, which results in EMT, thus plays an important role in the invasion and metastasis of gastric cancer.%目的 探讨Hedgehog(Hh)信号通路与上皮间质转换(Epithelial-mesenchymal transitions,EMT)在胃癌侵袭转移中的作用及分子机制.方法 分别用环靶明、Snail siRNA、空质粒及环靶明+Snail siRNA的混合物处理人胃癌SGC-7901细胞,并设常规培养对照组,48h后,采用RT-PCR法检测各组细胞中Gli1、Snail及E-cadherin基因mRNA的转录水平;Transwell小室试验检测细胞侵袭能力的变化;异质黏附试验检测各处理因素对细胞异质黏附能力的影响.结果 与对

  8. [Matrix metalloproteases as molecular markers in gastric cancer].

    Science.gov (United States)

    de la Peña, Sol; Sampieri, Clara L; León-Córdoba, Kenneth

    2010-02-01

    Gastric cancer is the second leading cause of cancer-associated mortality in the world. Prognosis in patients with gastric cancer is difficult to establish because it is commonly diagnosed when gastric wall invasion and metastasis have occurred. Currently, some members of the extracellular matrix metalloproteinases have been identified, whose expression in gastric tumor tissue is significantly elevated compared to healthy gastric tissue. Matrix metalloproteinases are 24 zinc-dependent endopeptidases that catalyze the proteolysis of the extracellular matrix. This degradation allows the cancer cells invade the surrounding stroma and trigger metastasis. Upregulation of certain matrix metalloproteinases in gastric cancer has been associated with a poor prognosis and elevated invasive capacity. This review compiles evidence about the genetic expression of matrix metalloproteinases in gastric cancer and their role in tumour invasion and metastasis, emphasizing their potential as molecular markers of prognosis.

  9. 2. Molecular Biology as a Tool in Cancer Epidemiology

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@There can be little doubt that we are entering a new era in our understanding of the origins of human cancer. Unfortunately from the point of view of the cancer epidemiology community, some of the more recent advances in the molecular biology of cancer (once fully assimilated) will tend to make the talk of the up-to-date cancer epidemiologist a great deal less straightforward than many of us had previously envisaged it to be, There may still be a few cancers that will prove to result from only a few distinctive types of mutation in a relatively small number of genes, but I strongly suspect that the great majority of human cancers that we wish to study will prove to have their origins in a complex set of DNA changes whose precise

  10. Molecular genetics of breast cancer progression

    OpenAIRE

    Sigurður Ingvarsson 1956

    1999-01-01

    Somatic changes in the genome of breast cancer cells include amplifications, deletions and gene mutations. Several chromosome regions harboring known oncogenes are found amplified in breast tumors. Despite the high number of chromosome regions deleted in breast tumors the functional relationship to known genes at these locations and cancer growth is mainly undiscovered. Mutations in two tumor suppressor genes (TSG) have been described in a subset of breast carcinomas. These TSG are the TP53, ...

  11. The cognitive life of mechanical molecular models.

    Science.gov (United States)

    Charbonneau, Mathieu

    2013-12-01

    The use of physical models of molecular structures as research tools has been central to the development of biochemistry and molecular biology. Intriguingly, it has received little attention from scholars of science. In this paper, I argue that these physical models are not mere three-dimensional representations but that they are in fact very special research tools: they are cognitive augmentations. Despite the fact that they are external props, these models serve as cognitive tools that augment and extend the modeler's cognitive capacities and performance in molecular modeling tasks. This cognitive enhancement is obtained because of the way the modeler interacts with these models, the models' materiality contributing to the solving of the molecule's structure. Furthermore, I argue that these material models and their component parts were designed, built and used specifically to serve as cognitive facilitators and cognitive augmentations.

  12. Molecular targeted agents for gastric and gastroesophageal junction cancer.

    Science.gov (United States)

    Oshima, Takashi; Masuda, Munetaka

    2012-04-01

    Despite recent improvements in surgical techniques and chemotherapy, advanced cancers of the stomach and gastroesophageal junction (GEJ) continue to have poor clinical outcomes. However, molecules intimately related to cancer cell proliferation, invasion, and metastasis have been studied as candidates for molecular targeted agents. Target molecules, such as the epidermal growth factor receptor, vascular endothelial growth factor receptor, and P13k/Akt/mTor pathway, as well as the insulin-like growth factor receptor, c-Met pathways, fibroblast growth factor receptor, and other pathways are considered to be promising candidates for molecular targeted therapy for gastric and GEJ cancer. In this review we focus on the recent developments in targeting relevant pathways in these types of cancer.

  13. Fasting: Molecular Mechanisms and Clinical Applications

    OpenAIRE

    Longo, Valter D.; Mattson, Mark P.

    2014-01-01

    Fasting has been practiced for millennia, but only recently studies have shed light on its role in adaptive cellular responses that reduce oxidative damage and inflammation, optimize energy metabolism and bolster cellular protection. In lower eukaryotes, chronic fasting extends longevity in part by reprogramming metabolic and stress resistance pathways. In rodents intermittent or periodic fasting protects against diabetes, cancers, heart disease and neurodegeneration, while in humans it helps...

  14. Quantum mechanics of molecular rate processes

    CERN Document Server

    Levine, Raphael D

    1999-01-01

    This survey of applications of the theory of collisions and rate processes to molecular problems explores collisions of molecules with internal structure, generalized Ehrenfest theorem, theory of reactive collisions, and role of symmetry. It also reviews partitioning technique, equivalent potentials and quasibound states, theory of direct reactions, more. 1969 edition.

  15. CD24 as a Molecular Marker in Ovarian Cancer: A Literature Review

    Directory of Open Access Journals (Sweden)

    Lu Huang

    2016-01-01

    Full Text Available Ovarian cancer is the most lethal gynecologic cancer, with a mortality rate of > 60%. Cancer stem cell (CSC hypothesis offers an attractive explanation of chemoresistance, metastasis, etc., associated with the disease. However, there are still controversy and limitation in defining the CSC markers. CD24 is a mucin-type glycosyl-phosphatidylinositol-linked glycoprotein, expressed on the surface of cells, which serves as a normal receptor for P-selectin and is found involved in molecular adhesion and metastatic tumor spread. Expression rate of CD24 has been associated with progression of various cancers and poor survival rates. In this review, the function of CD24 in ovarian cancer, especially in ovarian CSC system, was discussed in an effort to broaden the interpretation of potential mechanism.

  16. Epidemiological-molecular evidence of metabolic reprogramming on proliferation, autophagy and cell signaling in pancreas cancer.

    Science.gov (United States)

    Søreide, Kjetil; Sund, Malin

    2015-01-28

    Pancreatic cancer remains one of the deadliest human cancers with little progress made in survival over the past decades, and 5-year survival usually below 5%. Despite this dismal scenario, progresses have been made in understanding of the underlying tumor biology through among other definition of precursor lesions, delineation of molecular pathways, and advances in genome-wide technology. Further, exploring the relationship between epidemiological risk factors involving metabolic features to that of an altered cancer metabolism may provide the foundation for new therapies. Here we explore how nutrients and caloric intake may influence the KRAS-driven ductal carcinogenesis through mediators of metabolic stress, including autophagy in presence of TP53, advanced glycation end products (AGE) and the receptors (RAGE) and ligands (HMGB1), as well as glutamine pathways, among others. Effective understanding the cancer metabolism mechanisms in pancreatic cancer may propose new ways of prevention and treatment. PMID:24704294

  17. Effects and potential mechanisms of exercise training on cancer progression: a translational perspective.

    Science.gov (United States)

    Betof, Allison S; Dewhirst, Mark W; Jones, Lee W

    2013-03-01

    Over the past decade there has been increasing research and clinical interest in the role of exercise therapy/rehabilitation as an adjunct therapy to improve symptom control and management following a cancer diagnosis. More recently, the field of 'exercise - oncology' has broadened in scope to investigate whether the benefits extend beyond symptom control to modulate cancer-specific outcomes (i.e., cancer progression and metastasis). Here we review the extant epidemiological evidence examining the association between exercise behavior, functional capacity/exercise capacity, and cancer-specific recurrence and mortality as well as all-cause mortality individuals following a cancer diagnosis. We also evaluate evidence from clinical studies investigating the effects of structured exercise on blood-based biomarkers associated with cancer progression/metastasis as well findings from preclinical investigations examining the effects and molecular mechanisms of exercise in mouse models of cancer. Current gaps in knowledge are also discussed. PMID:22610066

  18. Choline metabolism-based molecular diagnosis of cancer: an update

    OpenAIRE

    Glunde, Kristine; Penet, Marie-France; Jiang, Lu; Jacobs, Michael A.; Zaver M Bhujwalla

    2015-01-01

    Abnormal choline metabolism continues to be identified in multiple cancers. Molecular causes of abnormal choline metabolism are changes in choline kinase-α, ethanolamine kinase-α, phosphatidylcholine-specific phospholipase C and -D and glycerophosphocholine phosphodiesterases, as well as several choline transporters. The net outcome of these enzymatic changes is an increase in phosphocholine and total choline (tCho) and, in some cancers, a relative decrease of glycerophosphocholine. The incre...

  19. Integrated molecular portrait of non-small cell lung cancers

    OpenAIRE

    Lazar, Vladimir; Suo, Chen; Orear, Cedric; van den Oord, Joost; Balogh, Zsofia; Guegan, Justine; Job, Bastien; Meurice, Guillaume; Ripoche, Hugues; Calza, Stefano; Hasmats, Johanna; Lundeberg, Joakim; Lacroix, Ludovic; Vielh, Philippe; Dufour, Fabienne

    2013-01-01

    Background Non-small cell lung cancer (NSCLC), a leading cause of cancer deaths, represents a heterogeneous group of neoplasms, mostly comprising squamous cell carcinoma (SCC), adenocarcinoma (AC) and large-cell carcinoma (LCC). The objectives of this study were to utilize integrated genomic data including copy-number alteration, mRNA, microRNA expression and candidate-gene full sequencing data to characterize the molecular distinctions between AC and SCC. Methods Comparative genomic hybridiz...

  20. [Molecular classification of bladder cancer. Possible similarities to breast cancer].

    Science.gov (United States)

    Wirtz, R M; Fritz, V; Stöhr, R; Hartmann, A

    2016-02-01

    Therapeutic decisions for breast cancer are increasingly becoming based on subtype-specific gene expression tests. For bladder cancer very similar subtypes have been identified by genome-wide mRNA analysis, which as for breast cancer differ with respect to the prognosis and response to therapy on the basis of their hormone dependency. At the DNA level, however, the type of mutations and their frequencies within the subtypes are strikingly different between bladder and breast cancers. It will be interesting to see whether possible driver mutations can serve as therapeutic targets in both indications. In contrast, the apparent hormone dependency of a substantial number of bladder carcinomas suggests that hormonal and anti-hormonal treatment can be valid therapy options similar to breast cancer. Moreover, gender-specific differences with respect to the incidence and aggressiveness of male compared to female bladder cancers can be explained by hormonal effects. Together with forthcoming immunomodulatory therapies these multiple therapy options raise and give new hope to efficiently combat this aggressive disease. PMID:26780243

  1. Colorectal Cancer & Molecular Mutations and Polymorphism

    Directory of Open Access Journals (Sweden)

    Aga Syed Sameer

    2013-05-01

    Full Text Available Colorectal cancer (CRC is one of the major causes of mortality and morbidity, and is the third most common cancer in men and the second most common cancer in women worldwide. The incidence of CRC shows considerable variation among racially or ethnically defined populations in multiracial/ethnic countries. The tumorigenesis of CRC is either because of the chromosomal instability (CIN or microsatellite instability (MIN or involving various proto-oncogenes, tumor suppressor genes and also epigenetic changes in the DNA. In this review I have focused on the mutations and polymorphisms of various important genes of the CIN and MIN pathways which have been implicated in the development of CRC.

  2. The Landscape of Pancreatic Cancer Therapeutic Resistance Mechanisms.

    Science.gov (United States)

    Chand, Saswati; O'Hayer, Kevin; Blanco, Fernando F; Winter, Jordan M; Brody, Jonathan R

    2016-01-01

    Pancreatic cancer (pancreatic ductal adenocarcinoma, PDA) is infamously moving to the top of the list as one of the most lethal cancers with an overall 5 year survival rate of 7%. Multiple genomic-based and molecular characterization studies of PDA specimens and established animal models have provided the field with multiple targets and a progression model of this disease. Still, to date, the best therapeutic options are surgery and combination cytotoxic therapies. In general, even in the best case scenario (i.e., an early stage diagnosis and a response to a specific therapy), most of these fortunate patients' PDA cells acquire or exert resistance mechanisms and eventually kill the patient. Herein, we touch on a growing field of investigation that focuses on PDA cell therapeutic resistance mechanisms. We examine extrinsic elements (i.e., the tumor microenvironment, hypoxia) to the intrinsic processes within the cell (i.e., post-transcriptional gene regulation and somatic mutations) that are important for therapeutic efficacy and resistance. Even as better targeted and personalized approaches move through the clinical trial pipeline the discussed resistance mechanisms will most likely play a role in the management of this deadly disease.

  3. Molecular Concordance Between Primary Breast Cancer and Matched Metastases.

    Science.gov (United States)

    Krøigård, Anne Bruun; Larsen, Martin Jakob; Thomassen, Mads; Kruse, Torben A

    2016-07-01

    Clinical management of breast cancer is increasingly personalized and based on molecular profiling. Often, primary tumors are used as proxies for systemic disease at the time of recurrence. However, recent studies have revealed substantial discordances between primary tumors and metastases, both with respect to traditional clinical treatment targets and on the genomic and transcriptomic level. With the increasing use of molecularly targeted therapy, discordance of actionable molecular targets between primary tumors and recurrences can result in nonoptimal treatment or unnecessary side effects. The purpose of this review is to illuminate the extent of cancer genome evolution through disease progression and the degree of molecular concordance between primary breast cancers and matched metastases. We present an overview of the most prominent studies investigating the expression of endocrine receptors, transcriptomics, and genome aberrations in primary tumors and metastases. In conclusion, biopsy of metastatic lesions at recurrence of breast cancer is encouraged to provide optimal treatment of the disease. Furthermore, molecular profiling of metastatic tissue provides invaluable mechanistic insight into the biology underlying metastatic progression and has the potential to identify novel, potentially druggable, drivers of progression. PMID:27089067

  4. Correlation of morphological and molecular parameters for colon cancer

    Science.gov (United States)

    Yuan, Shuai; Roney, Celeste A.; Li, Qian; Jiang, James; Cable, Alex; Summers, Ronald M.; Chen, Yu

    2010-02-01

    Colorectal cancer (CRC) is the second leading cause of cancer death in the United States. There is great interest in studying the relationship among microstructures and molecular processes of colorectal cancer during its progression at early stages. In this study, we use our multi-modality optical system that could obtain co-registered optical coherence tomography (OCT) and fluorescence molecular imaging (FMI) images simultaneously to study CRC. The overexpressed carbohydrate α-L-fucose on the surfaces of polyps facilitates the bond of adenomatous polyps with UEA-1 and is used as biomarker. Tissue scattering coefficient derived from OCT axial scan is used as quantitative value of structural information. Both structural images from OCT and molecular images show spatial heterogeneity of tumors. Correlations between those values are analyzed and demonstrate that scattering coefficients are positively correlated with FMI signals in conjugated. In UEA-1 conjugated samples (8 polyps and 8 control regions), the correlation coefficient is ranged from 0.45 to 0.99. These findings indicate that the microstructure of polyps is changed gradually during cancer progression and the change is well correlated with certain molecular process. Our study demonstrated that multi-parametric imaging is able to simultaneously detect morphology and molecular information and it can enable spatially and temporally correlated studies of structure-function relationships during tumor progression.

  5. Molecular mechanisms involved in convergent crop domestication.

    Science.gov (United States)

    Lenser, Teresa; Theißen, Günter

    2013-12-01

    Domestication has helped to understand evolution. We argue that, vice versa, novel insights into evolutionary principles could provide deeper insights into domestication. Molecular analyses have demonstrated that convergent phenotypic evolution is often based on molecular changes in orthologous genes or pathways. Recent studies have revealed that during plant domestication the causal mutations for convergent changes in key traits are likely to be located in particular genes. These insights may contribute to defining candidate genes for genetic improvement during the domestication of new plant species. Such efforts may help to increase the range of arable crops available, thus increasing crop biodiversity and food security to help meet the predicted demands of the continually growing global population under rapidly changing environmental conditions.

  6. Cellular and molecular mechanisms underlying muscular dystrophy

    OpenAIRE

    Rahimov, Fedik; Kunkel, Louis M

    2013-01-01

    The muscular dystrophies are a group of heterogeneous genetic diseases characterized by progressive degeneration and weakness of skeletal muscle. Since the discovery of the first muscular dystrophy gene encoding dystrophin, a large number of genes have been identified that are involved in various muscle-wasting and neuromuscular disorders. Human genetic studies complemented by animal model systems have substantially contributed to our understanding of the molecular pathomechanisms underlying ...

  7. Comparative Proteomic Analysis of Anti-Cancer Mechanism by Periplocin Treatment in Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Zejun Lu

    2014-03-01

    Full Text Available Background: Periplocin is used for treatment of rheumatoid arthritis, reinforcement of bones and tendons, palpitations or shortness of breath and lower extremity edema in traditional medicine. Our previous findings suggested that periplocin could inhibit the growth of lung cancer both in vitro and in vivo. But the biological processes and molecular pathways by which periplocin induces these beneficial effects remain largely undefined. Methods: To explore the molecular mechanisms of periplocin involved in anti-cancer activity, in the present study the protein profile changes of human lung cancer cell lines A549 in response to periplocin treatment were investigated using the proteomics approaches (2-DE combined with MS/MS. Western blot was employed to verify the changed proteins. Interactions between changed proteins were analyzed by STRING. Results: 29 down-regulated protein species named GTP-binding nuclear protein Ran (RAN, Rho GDP-dissociation inhibitor 1 (ARHGDIA, eukaryotic translation initiation factor 5A-1 (EIF5A and Profilin-1(PFN1, and 10 up-regulated protein species named Heat shock cognate 71 kDa protein (HSPA8,10 kDa heat shock protein (HSPE1, and Cofilin-1(CFL-1 were identified. Among them, GTP-binding nuclear protein Ran (RAN and Rho GDP-dissociation inhibitor 1 (ARHGDIA were the most significantly changed (over tenfold. The proteasome subunit beta type-6 (PSMB6, ATP synthase ecto-α-subunit (ATP5A1, Aldehyde dehydrogenase 1 (ALDH1 and EIF5A were verified by immunoblot assays to be dramatically down-regulated. By STRING bioinformatics analysis revealing interactions and signaling networks it became apparent that the proteins changed they are primarily involved in transcription and proteolysis. Conclusion: Periplocin inhibited growth of lung cancer by down-regulating proteins, such as ATP5A1, EIF5A, ALDH1 and PSMB6. These findings may improve our understanding of the molecular mechanisms underlying the anti-cancer effects of

  8. Endometrial cancer : from a molecular genetic perspective

    NARCIS (Netherlands)

    E. Smid-Koopman (Ellen)

    2002-01-01

    textabstractThe first observations indicative of a role of genetic factors in carcinogenesis were made as early as 1912, when Rous demonstrated that a filterable agent (i.e. virus) could induce cancer in chicken (Rous 1965). In 1914, Boveri postulated a "genetic" theory on carcinogenesis by hypothes

  9. Molecular pathology of colorectal cancer predisposing syndromes

    NARCIS (Netherlands)

    Puijenbroek, Marjo van

    2008-01-01

    Each year, approximately eleven thousand new colorectal cancer (CRC) patients are registered in the Netherlands. Half of these patients will eventually die of this disease. Consequently, it is of great importance to identify individuals with an increased risk for CRC. In this thesis, we evaluate the

  10. The consensus molecular subtypes of colorectal cancer

    NARCIS (Netherlands)

    Guinney, Justin; Dienstmann, Rodrigo; Wang, Xin; de Reyniès, Aurélien; Schlicker, Andreas; Soneson, Charlotte; Marisa, Laetitia; Roepman, Paul; Nyamundanda, Gift; Angelino, Paolo; Bot, Brian M; Morris, Jeffrey S; Simon, Iris M; Gerster, Sarah; Fessler, Evelyn; De Sousa E Melo, Felipe; Missiaglia, Edoardo; Ramay, Hena; Barras, David; Homicsko, Krisztian; Maru, Dipen; Manyam, Ganiraju C; Broom, Bradley; Boige, Valerie; Perez-Villamil, Beatriz; Laderas, Ted; Salazar, Ramon; Gray, Joe W; Hanahan, Douglas; Tabernero, Josep; Bernards, Rene; Friend, Stephen H; Laurent-Puig, Pierre; Medema, Jan Paul; Sadanandam, Anguraj; Wessels, Lodewyk; Delorenzi, Mauro; Kopetz, Scott; Vermeulen, Louis; Tejpar, Sabine

    2015-01-01

    Colorectal cancer (CRC) is a frequently lethal disease with heterogeneous outcomes and drug responses. To resolve inconsistencies among the reported gene expression-based CRC classifications and facilitate clinical translation, we formed an international consortium dedicated to large-scale data shar

  11. Molecular-Genetic Aspects of Breast Cancer

    Directory of Open Access Journals (Sweden)

    Krasteva M.

    2014-12-01

    Full Text Available Breast cancer is the most frequent malignancy among women. Advances in breast cancer knowledge have deciphered the involvement of a number of tumor suppressor genes and proto-oncogenes in disease pathogenesis. These genes are part of the complex biochemical pathways, which enable cell cycle control and maintenance of genome integrity. Their function may be disrupted as a result of alterations in gene sequence or misregulation of gene expression including alterations in DNA methylation pattern. The present review summarizes the main findings on major breast cancer related genes BRCA1/2, p53, ATM, CHEK2, HER2, PIK3CA and their tumorigenic inactivation/activation. The potential clinical importance of these genes with respect to patients’ prognosis and therapy are also discussed. The possible implication of other putative breast cancer related genes is also outlined. The first elaborate data on the genetic and epigenetic status of the above mentioned genes concerning Bulgarian patients with the sporadic form of the disease are presented. The studies indicate for a characteristic mutational spectrum in some of the genes for the Bulgarian patients and specific correlation between the status of different genes and clinicopathological characteristics.

  12. Molecular markers as therapeutic targets in lung cancer

    Institute of Scientific and Technical Information of China (English)

    Hsin-Hui Tseng; Biao He

    2013-01-01

    Lung cancer is responsible for 29% of cancer deaths in the United States and has very low 5-year survival rates of approximately 11% in men and 15% in women.Although the early diagnosis of lung cancer may increase the survival rate with adequate treatment,advanced lung cancers are often metastasized and receive limited benefit from therapeutic regimens.As conventional treatments for lung cancer reach their limitations,researchers have attempted to discover novel drug therapies aimed at specific targets contributing to the progression of tumorigenesis.Recent advances in systems biology have enabled the molecular biology of lung carcinogenesis to be elucidated.Our understanding of the physiologic processes of tumor development provide a means to design more effective and specific drugs with less toxicity,thereby accelerating the delivery of new drug therapies to the patient's bedside.

  13. Molecular and trophic mechanisms of tumorigenesis.

    Science.gov (United States)

    Levy, Andy

    2008-03-01

    A significant proportion of pituitary macroadenomas, and by definition all microadenomas, regain trophic stability after an initial period of deregulated growth. Classical proto-oncogene activation and tumor suppressor mutation are rarely responsible, and no histologic or molecular markers reliably predict behavior. GNAS1 activation and the mutations associated with multiple endocrine neoplasia type 1 and Carney complex, aryl hydrocarbon receptor interacting protein gene mutations, and a narrowing region of chromosome 11q13 in familial isolated acromegaly together account for such a small proportion of pituitary adenomas that the pituitary adenoma pathogenic epiphany is surely yet to come. PMID:18226729

  14. Oncogenic miR-544 is an important molecular target in gastric cancer.

    Science.gov (United States)

    Zhi, Qiaoming; Guo, Xiaobo; Guo, Lei; Zhang, Rongjuan; Jiang, Jinling; Ji, Jun; Zhang, Jianian; Zhang, Jun; Chen, Xuehua; Cai, Qu; Li, Jianfang; Liu, Bingya; Zhu, Zhenggang; Yu, Yingyan

    2013-02-01

    MicroRNAs (miRNAs) and promoter hypermethylation are vital epigenetic mechanisms for transcriptional inactivation of tumor suppressor. IRX1 is a newly identified tumor suppressor gene and hypermethylation involves the decreased expression in gastric cancer. However, the microRNA regulatory mechanism on IRX1 expression is still unclear. In this study, we report an IRX1-targeting miRNA-544, which directly targets 3'-UTR of IRX1 gene by luciferase reporter assay. miR-544 suppresses the protein expression of IRX1 gene by Western blot and immunocytochemistry. Ectopic expression of miR-544 promotes cell proliferation and cell cycle progression significantly in vitro on gastric cancer cells. The study suggests that miR-544 is an oncogenic microRNA in gastric cancer. Over expression of miR-544 contributes to the inactivation and low-expression of IRX1 in gastric cancer. These findings are helpful for clarifying the molecular mechanisms involved in gastric carcinogenesis and indicate that miR-544 is a key regulator in switching cell cycle on or off. miR-544 may be a potential molecular target in miRNA-based strategy on gastric cancer.

  15. Molecular and cellular mechanisms of pulmonary fibrosis

    Directory of Open Access Journals (Sweden)

    Todd Nevins W

    2012-07-01

    Full Text Available Abstract Pulmonary fibrosis is a chronic lung disease characterized by excessive accumulation of extracellular matrix (ECM and remodeling of the lung architecture. Idiopathic pulmonary fibrosis is considered the most common and severe form of the disease, with a median survival of approximately three years and no proven effective therapy. Despite the fact that effective treatments are absent and the precise mechanisms that drive fibrosis in most patients remain incompletely understood, an extensive body of scientific literature regarding pulmonary fibrosis has accumulated over the past 35 years. In this review, we discuss three broad areas which have been explored that may be responsible for the combination of altered lung fibroblasts, loss of alveolar epithelial cells, and excessive accumulation of ECM: inflammation and immune mechanisms, oxidative stress and oxidative signaling, and procoagulant mechanisms. We discuss each of these processes separately to facilitate clarity, but certainly significant interplay will occur amongst these pathways in patients with this disease.

  16. Integrating tumor microenvironment with cancer molecular classifications

    OpenAIRE

    Becht, Etienne; De Reyniès, Aurélien; Fridman, Wolf H.

    2015-01-01

    Editorial summary The composition of the tumor microenvironment is associated with a patient's prognosis and can be therapeutically targeted. A link between the cellular composition and genomic features of the tumor and its response to immunotherapy is beginning to emerge. Analyzing the microenvironment of tumor molecular subgroups can be a useful approach to tailor immunotherapies.

  17. TCGA divides gastric cancer into four molecular subtypes:implications for individualized therapeutics

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang

    2014-01-01

    Gastric cancer is a leading cause of cancer deaths in the world. The treatment of gastric cancer is chalenging because of its highly heterogeneous etiology and clinical characteristics. Recent genomic and molecular characterization of gastric cancer, especialy the findings reported by the Cancer Genome Atlas (TCGA), have shed light on the heterogeneity and potential targeted therapeutics for four different subtypes of gastric cancer.

  18. Molecular Imaging of Breast Cancer: Present and future directions

    Directory of Open Access Journals (Sweden)

    David eAlcantara

    2014-12-01

    Full Text Available Medical imaging technologies have undergone explosive growth over the past few decades and now play a central role in clinical oncology. But the truly transformative power of imaging in the clinical management of cancer patients lies ahead. Today, imaging is at a crossroads, with molecularly targeted imaging agents expected to broadly expand the capabilities of conventional anatomical imaging methods. Molecular imaging will allow clinicians to not only see where a tumour is located in the body, but also to visualize the expression and activity of specific molecules (e.g. proteases and protein kinases and biological processes (e.g. apoptosis, angiogenesis, and metastasis that influence tumour behavior and/or response to therapy. Breast cancer, the most common cancer among women and a research area where our group is actively involved, is a very heterogeneous disease with diverse patterns of development and response to treatment. Hence, molecular imaging is expected to have a major impact on this type of cancer, leading to important improvements in diagnosis, individualized treatment, and drug development, as well as our understanding of how breast cancer arises.

  19. Molecular Imaging of Breast Cancer: Present and future directions

    Science.gov (United States)

    Alcantara, David; Pernia Leal, Manuel; Garcia, Irene; Garcia-Martin, Maria Luisa

    2014-12-01

    Medical imaging technologies have undergone explosive growth over the past few decades and now play a central role in clinical oncology. But the truly transformative power of imaging in the clinical management of cancer patients lies ahead. Today, imaging is at a crossroads, with molecularly targeted imaging agents expected to broadly expand the capabilities of conventional anatomical imaging methods. Molecular imaging will allow clinicians to not only see where a tumour is located in the body, but also to visualize the expression and activity of specific molecules (e.g. proteases and protein kinases) and biological processes (e.g. apoptosis, angiogenesis, and metastasis) that influence tumour behavior and/or response to therapy. Breast cancer, the most common cancer among women and a research area where our group is actively involved, is a very heterogeneous disease with diverse patterns of development and response to treatment. Hence, molecular imaging is expected to have a major impact on this type of cancer, leading to important improvements in diagnosis, individualized treatment, and drug development, as well as our understanding of how breast cancer arises.

  20. Immunophenotyping invasive breast cancer: paving the road for molecular imaging.

    NARCIS (Netherlands)

    Vermeulen, J.F.; Brussel, A.S. van; Groep, P. van der; Morsink, F.H.; Bult, P.; Wall, E. van der; Diest, P.J. van

    2012-01-01

    ABSTRACT: BACKGROUND: Mammographic population screening in The Netherlands has increased the number of breast cancer patients with small and non-palpable breast tumors. Nevertheless, mammography is not ultimately sensitive and specific for distinct subtypes. Molecular imaging with targeted tracers m

  1. Review on the Applications and Molecular Mechanisms of Xihuang Pill in Tumor Treatment

    Directory of Open Access Journals (Sweden)

    Qiujun Guo

    2015-01-01

    Full Text Available Xihuang pill (XH is a complementary and alternative medicine that has been used in traditional Chinese medicine (TCM for the treatment of tumors since the 18th century. XH has clinical effects on non-Hodgkin lymphoma, breast cancer, gastric cancer, liver cancer, and bone metastasis. XH can also inhibit the growth of tumor cells and cancer stem cells, prevent tumor invasion and angiogenesis, and regulate the tumor microenvironment. XH is composed of Ru Xiang (olibanum, Mo Yao (Commiphora myrrha, She Xiang (Moschus, and Niu Huang (Calculus bovis. Some of the compounds found in these ingredients exert multiple antitumor effects and may synergize with the other ingredients. We aimed to summarize the clinical applications and molecular mechanisms of XH and its chemical composition. This review will provide potential new strategies and alternative perspectives for tumor treatments and basic research into complementary and alternative medicine.

  2. An Overview of Carcinogenic Heavy Metal: Molecular Toxicity Mechanism and Prevention

    Science.gov (United States)

    Kim, Hyun Soo; Kim, Yeo Jin; Seo, Young Rok

    2015-01-01

    Almost all heavy metals are serious toxicants as carcinogens. However, due to their chemical and physiological properties, heavy metals are useful in industrial areas including alloy, smelting and production of commercial products. Such applications increase the opportunity for heavy metal exposure. Waste from industrial processes is also a major source of environmental contamination and accumulation in the human body. Arsenic, cadmium, chromium, and nickel are classified as group 1 carcinogens by the International Agency for Research on Cancer, and are utilized commercially. In this review, we used molecular pathway analysis to understand the toxicity and carcinogenic mechanisms of these metals. Our analyzed data showed that above-mentioned metallic substances induce oxidative stress, DNA damage, and cell death processes, resulting in increase the risk of cancer and cancer-related diseases. Thus, we might think phytochelatin molecules and antioxidative phytochemical substances are helpful for prevention of heavy metal-induced cancer. PMID:26734585

  3. Review on the Applications and Molecular Mechanisms of Xihuang Pill in Tumor Treatment.

    Science.gov (United States)

    Guo, Qiujun; Lin, Jinyin; Liu, Rui; Gao, Yebo; He, Shulin; Xu, Xinyao; Hua, Baojin; Li, Conghuang; Hou, Wei; Zheng, Honggang; Bao, Yanju

    2015-01-01

    Xihuang pill (XH) is a complementary and alternative medicine that has been used in traditional Chinese medicine (TCM) for the treatment of tumors since the 18th century. XH has clinical effects on non-Hodgkin lymphoma, breast cancer, gastric cancer, liver cancer, and bone metastasis. XH can also inhibit the growth of tumor cells and cancer stem cells, prevent tumor invasion and angiogenesis, and regulate the tumor microenvironment. XH is composed of Ru Xiang (olibanum), Mo Yao (Commiphora myrrha), She Xiang (Moschus), and Niu Huang (Calculus bovis). Some of the compounds found in these ingredients exert multiple antitumor effects and may synergize with the other ingredients. We aimed to summarize the clinical applications and molecular mechanisms of XH and its chemical composition. This review will provide potential new strategies and alternative perspectives for tumor treatments and basic research into complementary and alternative medicine.

  4. Review on the Applications and Molecular Mechanisms of Xihuang Pill in Tumor Treatment.

    Science.gov (United States)

    Guo, Qiujun; Lin, Jinyin; Liu, Rui; Gao, Yebo; He, Shulin; Xu, Xinyao; Hua, Baojin; Li, Conghuang; Hou, Wei; Zheng, Honggang; Bao, Yanju

    2015-01-01

    Xihuang pill (XH) is a complementary and alternative medicine that has been used in traditional Chinese medicine (TCM) for the treatment of tumors since the 18th century. XH has clinical effects on non-Hodgkin lymphoma, breast cancer, gastric cancer, liver cancer, and bone metastasis. XH can also inhibit the growth of tumor cells and cancer stem cells, prevent tumor invasion and angiogenesis, and regulate the tumor microenvironment. XH is composed of Ru Xiang (olibanum), Mo Yao (Commiphora myrrha), She Xiang (Moschus), and Niu Huang (Calculus bovis). Some of the compounds found in these ingredients exert multiple antitumor effects and may synergize with the other ingredients. We aimed to summarize the clinical applications and molecular mechanisms of XH and its chemical composition. This review will provide potential new strategies and alternative perspectives for tumor treatments and basic research into complementary and alternative medicine. PMID:26170886

  5. Molecular Mechanisms of Action of BPA.

    Science.gov (United States)

    Acconcia, Filippo; Pallottini, Valentina; Marino, Maria

    2015-01-01

    Bisphenol A (BPA) exposure has been associated with serious endocrine-disrupting effects in humans and wildlife. Toxicological and epidemiological studies evidenced that BPA increases body mass index and disrupts normal cardiovascular physiology by interfering with endogenous hormones in rodents, nonhuman primates, and cell culture test systems. The BPA concentration derived from these experiments were used by government regulatory agencies to determine the safe exposure levels of BPA in humans. However, accumulating literature in vivo and in vitro indicate that at concentrations lower than that reported in toxicological studies, BPA could elicit a different endocrine-disrupting capacity. To further complicate this picture, BPA effects rely on several and diverse mechanisms that converge upon endocrine and reproductive systems. If all or just few of these mechanisms concur to the endocrine-disrupting potential of low doses of BPA is at present still unclear. Thus, taking into account that the incidence and/or prevalence of health problems associated with endocrine disruption have increased worldwide, the goal of the present review is to give an overview of the many mechanisms of BPA action in order to decipher whether different mechanisms are at the root of the effect of low dose of BPA on endocrine system. PMID:26740804

  6. Molecular Mechanisms of Action of BPA

    Directory of Open Access Journals (Sweden)

    Filippo Acconcia

    2015-10-01

    Full Text Available Bisphenol A (BPA exposure has been associated with serious endocrine-disrupting effects in humans and wildlife. Toxicological and epidemiological studies evidenced that BPA increases body mass index and disrupts normal cardiovascular physiology by interfering with endogenous hormones in rodents, nonhuman primates, and cell culture test systems. The BPA concentration derived from these experiments were used by government regulatory agencies to determine the safe exposure levels of BPA in humans. However, accumulating literature in vivo and in vitro indicate that at concentrations lower than that reported in toxicological studies, BPA could elicit a different endocrine-disrupting capacity. To further complicate this picture, BPA effects rely on several and diverse mechanisms that converge upon endocrine and reproductive systems. If all or just few of these mechanisms concur to the endocrine-disrupting potential of low doses of BPA is at present still unclear. Thus, taking into account that the incidence and/or prevalence of health problems associated with endocrine disruption have increased worldwide, the goal of the present review is to give an overview of the many mechanisms of BPA action in order to decipher whether different mechanisms are at the root of the effect of low dose of BPA on endocrine system.

  7. Mechanism of Molecular Exchange in Copolymer Micelles

    Science.gov (United States)

    Choi, Soo-Hyung; Lodge, Timothy; Bates, Frank

    2010-03-01

    Compared to thermodynamic structure, much less has been known about the kinetics of block copolymer micelles which should underlay the attainment of thermodynamic equilibrium. In this presentation, molecular exchange between spherical micelles formed by isotopically labeled diblock copolymers was investigated using time-resolved small-angle neutron scattering. Two pairs of structurally matched poly(styrene-b-ethylene-alt-propylene) (PS-PEP) were synthesized and dispersed in isotopic mixture of squalane, highly selective to PEP block. Each pair includes polymers with fully deuterated (dPS-PEP) and a normal (hPS-PEP) PS blocks. Temperature dependence of the micelle exchange rate R(t) is consistent with melt dynamics for the core polymer. Furthermore, R(t) is significantly sensitive to the core block length N due to the thermodynamic penalty associated with ejecting a core block into the solvent. This hypersensitivity, combined with modest polydispersity in N, leads to an approximately logarithmic decay in R(t).

  8. Male sex determination: insights into molecular mechanisms

    Institute of Scientific and Technical Information of China (English)

    Kathryn McClelland; Josephine Bowles; Peter Koopman

    2012-01-01

    Disorders of sex development often arise from anomalies in the molecular or cellular networks that guide the differentiation of the embryonic gonad into either a testis or an ovary,two functionally distinct organs.The activation of the Y-linked gene Sry(sexdetermining region Y) and its downstream target Sox9 (Sry box-containinggene 9) triggers testis differentiation by stimulating the differentiation of Sertoli cells,which then direct testis morphogenesis.Once engaged,a genetic pathway promotes the testis development while actively suppressing genes involved in ovarian development.This review focuses on the events of testis determination and the struggle to maintain male fate in the face of antagonistic pressure from the underlying female programme.

  9. Evolving molecularly targeted therapies for advanced-stage thyroid cancers.

    Science.gov (United States)

    Bible, Keith C; Ryder, Mabel

    2016-07-01

    Increased understanding of disease-specific molecular targets of therapy has led to the regulatory approval of two drugs (vandetanib and cabozantinib) for the treatment of medullary thyroid cancer (MTC), and two agents (sorafenib and lenvatinib) for the treatment of radioactive- iodine refractory differentiated thyroid cancer (DTC) in both the USA and in the EU. The effects of these and other therapies on overall survival and quality of life among patients with thyroid cancer, however, remain to be more-clearly defined. When applied early in the disease course, intensive multimodality therapy seems to improve the survival outcomes of patients with anaplastic thyroid cancer (ATC), but salvage therapies for ATC are of uncertain benefit. Additional innovative, rationally designed therapeutic strategies are under active development both for patients with DTC and for patients with ATC, with multiple phase II and phase III randomized clinical trials currently ongoing. Continued effort is being made to identify further signalling pathways with potential therapeutic relevance in thyroid cancers, as well as to elaborate on the complex interactions between signalling pathways, with the intention of translating these discoveries into effective and personalized therapies. Herein, we summarize the progress made in molecular medicine for advanced-stage thyroid cancers of different histotypes, analyse how these developments have altered - and might further refine - patient care, and identify open questions for future research. PMID:26925962

  10. Identification of a novel luminal molecular subtype of breast cancer.

    Directory of Open Access Journals (Sweden)

    Anna Dvorkin-Gheva

    Full Text Available The molecular classification of human breast tumors has afforded insights into subtype specific biological processes, patient prognosis and response to therapies. However, using current methods roughly one quarter of breast tumors cannot be classified into one or another molecular subtype. To explore the possibility that the unclassifiable samples might comprise one or more novel subtypes we employed a collection of publically available breast tumor datasets with accompanying clinical information to assemble 1,593 transcript profiles: 25% of these samples could not be assigned to one of the current molecular subtypes of breast cancer. All of the unclassifiable samples could be grouped into a new molecular subtype, which we termed "luminal-like". We also identified the luminal-like subtype in an independent collection of tumor samples (NKI295. We found that patients harboring tumors of the luminal-like subtype have a better prognosis than those with basal-like breast cancer, a similar prognosis to those with ERBB2+, luminal B or claudin-low tumors, but a worse prognosis than patients with luminal A or normal-like breast tumors. Our findings suggest the occurrence of another molecular subtype of breast cancer that accounts for the vast majority of previously unclassifiable breast tumors.

  11. Normal and disease-related biological functions of Twist1 and underlying molecular mechanisms

    Institute of Scientific and Technical Information of China (English)

    Qian Qin; Young Xu; Tao He; Chunlin Qin; Jianming Xu

    2012-01-01

    This article reviews the molecular structure,expression pattern,physiological function,pathological roles and molecular mechanisms of Twist1 in development,genetic disease and cancer.Twist1 is a basic helix-loop-helix domaincontaining transcription factor.It forms homo- or hetero-dimers in order to bind the Nde1 E-box element and activate or repress its target genes.During development,Twistl is essential for mesoderm specification and differentiation.Heterozygous loss-of-function mutations of the human Twist1 gene cause several diseases including the SaethreChotzen syndrome.The Twist1-null mouse embryos die with unclosed cranial neural tubes and defective head mesenchyme,somites and limb buds.Twist1 is expressed in breast,liver,prostate,gastric and other types of cancers,and its expression is usually associated with invasive and metastatic cancer phenotypes.In cancer cells,Twistl is upregulated by multiple factors including SRC-1,STAT3,MSX2,HIF-1α,integrin-linked kinase and NF-κB.Twist1 significantly enhances epithelial-mesenchymal transition (EMT) and cancer cell migration and invasion,hence promoting cancer metastasis.Twistl promotes EMT in part by directly repressing E-cadherin expression by recruiting the nucleosome remodeling and deacetylase complex for gene repression and by upregulating Bmil,AKT2,YB-1,etc.Emerging evidence also suggests that Twist1 plays a role in expansion and chemotherapeutic resistance of cancer stem cells.Further understanding of the mechanisms by which Twist1 promotes metastasis and identification of Twist1 functional modulators may hold promise for developing new strategies to inhibit EMT and cancer metastasis.

  12. Pathological Bases for a Robust Application of Cancer Molecular Classification

    Directory of Open Access Journals (Sweden)

    Salvador J. Diaz-Cano

    2015-04-01

    Full Text Available Any robust classification system depends on its purpose and must refer to accepted standards, its strength relying on predictive values and a careful consideration of known factors that can affect its reliability. In this context, a molecular classification of human cancer must refer to the current gold standard (histological classification and try to improve it with key prognosticators for metastatic potential, staging and grading. Although organ-specific examples have been published based on proteomics, transcriptomics and genomics evaluations, the most popular approach uses gene expression analysis as a direct correlate of cellular differentiation, which represents the key feature of the histological classification. RNA is a labile molecule that varies significantly according with the preservation protocol, its transcription reflect the adaptation of the tumor cells to the microenvironment, it can be passed through mechanisms of intercellular transference of genetic information (exosomes, and it is exposed to epigenetic modifications. More robust classifications should be based on stable molecules, at the genetic level represented by DNA to improve reliability, and its analysis must deal with the concept of intratumoral heterogeneity, which is at the origin of tumor progression and is the byproduct of the selection process during the clonal expansion and progression of neoplasms. The simultaneous analysis of multiple DNA targets and next generation sequencing offer the best practical approach for an analytical genomic classification of tumors.

  13. Application of Proteomics to Cancer Molecular Diagnostics

    Institute of Scientific and Technical Information of China (English)

    Sam HANASH

    2009-01-01

    @@ Strategies to achieve personalized medicine and improve public health encompass assessment of an individual's risk for disease, early detection and molecular classification of disease resulting in an informed choice of the most appropriate treatment instituted at an early stage of disease develop- ment. A major contribution of proteomics in this field is the development of blood based tests to achieve the goals of personalized medicine.

  14. Molecular Mechanisms of Lymphocyte-Mediated Cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    Zusen Fan; Qixiang Zhang

    2005-01-01

    Granule-mediated cytotoxicity is the major mechanism for lymphocytes to kill viruses, intracellular bacteria and tumors. The cytotoxic granules move to the immunological synapse by exocytosis after recognition of a killer cell.The contents of the granules are delivered into target cells with the help of perforin by endocytosis. A group of serine protease granzymes cleave their critical substrates to initiate DNA damage and cell death. The most abundant granzymes are granzyme A and B. They induce cell death through alternate and nonoverlapping pathways. The substrates and functions of the majority of the orphan granzymes have not yet been identified. It is possible that the diversity of granzymes provides fail-safe mechanisms for killing viruses and tumor cells.

  15. Xenon preconditioning: molecular mechanisms and biological effects

    Directory of Open Access Journals (Sweden)

    Liu Wenwu

    2013-01-01

    Full Text Available Abstract Xenon is one of noble gases and has been recognized as an anesthetic for more than 50 years. Xenon possesses many of the characteristics of an ideal anesthetic, but it is not widely applied in clinical practice mainly because of its high cost. In recent years, numerous studies have demonstrated that xenon as an anesthetic can exert neuroprotective and cardioprotective effects in different models. Moreover, xenon has been applied in the preconditioning, and the neuroprotective and cardioprotective effects of xenon preconditioning have been investigated in a lot of studies in which some mechanisms related to these protections are proposed. In this review, we summarized these mechanisms and the biological effects of xenon preconditioning.

  16. Vancomycin Molecular Interactions: Antibiotic and Enantioselective Mechanisms

    Science.gov (United States)

    Ward, Timothy J.; Gilmore, Aprile; Ward, Karen; Vowell, Courtney

    Medical studies established that vancomycin and other related macrocyclic antibiotics have an enhanced antimicrobial activity when they are associated as dimers. The carbohydrate units attached to the vancomycin basket have an essential role in the dimerization reaction. Covalently synthesized dimers were found active against vancomycin-resistant bacterial strains. A great similarity between antibiotic potential and enantioselectivity was established. A covalent vancomycin dimer was studied in capillary electrophoresis producing excellent chiral separation of dansyl amino acids. Balhimycin is a macrocyclic glycopeptide structurally similar to vancomycin. The small differences are, however, responsible for drastic differences in enantioselectivity in the same experimental conditions. Contributions from studies examining vancomycin's mechanism for antimicrobial activity have substantially aided our understanding of its mechanism in chiral recognition.

  17. Molecular Mechanisms of Sleep and Mood

    OpenAIRE

    Lagus, Markus

    2013-01-01

    BACKGROUND Sleep disturbances and mood alterations are highly interrelated. The majority of patients suffering from depression report a reduced sleep quality. Inversely, people with sleep complaints are at elevated risk to develop depression. The complex regulation of these phenomena involves several brain areas and mechanisms. The susceptibility to change in this system is influenced by several factors, such as age and stressful lifestyle that are considered in this study. HYPOTHESIS The hyp...

  18. Molecular mechanisms of bone formation in spondyloarthritis.

    Science.gov (United States)

    González-Chávez, Susana Aideé; Quiñonez-Flores, Celia María; Pacheco-Tena, César

    2016-07-01

    Spondyloarthritis comprise a group of inflammatory rheumatic diseases characterized by its association to HLA-B27 and the presence of arthritis and enthesitis. The pathogenesis involves both an inflammatory process and new bone formation, which eventually lead to ankylosis of the spine. To date, the intrinsic mechanisms of the pathogenic process have not been fully elucidated, and our progress is remarkable in the identification of therapeutic targets to achieve the control of the inflammatory process, yet our ability to inhibit the excessive bone formation is still insufficient. The study of new bone formation in spondyloarthritis has been mostly conducted in animal models of the disease and only few experiments have been done using human biopsies. The deregulation and overexpression of molecules involved in the osteogenesis process have been observed in bone cells, mesenchymal cells, and fibroblasts. The signaling associated to the excessive bone formation is congruent with those involved in the physiological processes of bone remodeling. Bone morphogenetic proteins and Wnt pathways have been found deregulated in this disease; however, the cause for uncontrolled stimulation remains unknown. Mechanical stress appears to play an important role in the pathological osteogenesis process; nevertheless, the association of other important factors, such as the presence of HLA-B27 and environmental factors, remains uncertain. The present review summarizes the experimental findings that describe the signaling pathways involved in the new bone formation process in spondyloarthritis in animal models and in human biopsies. The role of mechanical stress as the trigger of these pathways is also reviewed. PMID:26838262

  19. Molecular Pathways: Cachexia Signaling-A Targeted Approach to Cancer Treatment.

    Science.gov (United States)

    Miyamoto, Yuji; Hanna, Diana L; Zhang, Wu; Baba, Hideo; Lenz, Heinz-Josef

    2016-08-15

    Cancer cachexia is a multifactorial syndrome characterized by an ongoing loss of skeletal muscle mass, which negatively affects quality of life and portends a poor prognosis. Numerous molecular substrates and mechanisms underlie the dysregulation of skeletal muscle synthesis and degradation observed in cancer cachexia, including proinflammatory cytokines (TNFα, IL1, and IL6), and the NF-κB, IGF1/AKT/mTOR, and myostatin/activin-SMAD pathways. Recent preclinical and clinical studies have demonstrated that anti-cachexia drugs (such as MABp1 and soluble receptor antagonist of myostatin/activin) not only prevent muscle wasting but also may prolong overall survival. In this review, we focus on the significance of cachexia signaling in patients with cancer and highlight promising drugs targeting tumor cachexia in clinical development. Clin Cancer Res; 22(16); 3999-4004. ©2016 AACR.

  20. Membrane curvature in cell biology: An integration of molecular mechanisms.

    Science.gov (United States)

    Jarsch, Iris K; Daste, Frederic; Gallop, Jennifer L

    2016-08-15

    Curving biological membranes establishes the complex architecture of the cell and mediates membrane traffic to control flux through subcellular compartments. Common molecular mechanisms for bending membranes are evident in different cell biological contexts across eukaryotic phyla. These mechanisms can be intrinsic to the membrane bilayer (either the lipid or protein components) or can be brought about by extrinsic factors, including the cytoskeleton. Here, we review examples of membrane curvature generation in animals, fungi, and plants. We showcase the molecular mechanisms involved and how they collaborate and go on to highlight contexts of curvature that are exciting areas of future research. Lessons from how membranes are bent in yeast and mammals give hints as to the molecular mechanisms we expect to see used by plants and protists.

  1. Molecular Mechanisms of Circadian Regulation During Spaceflight

    Science.gov (United States)

    Zanello, S. B.; Boyle, R.

    2012-01-01

    The physiology of both vertebrates and invertebrates follows internal rhythms coordinated in phase with the 24-hour daily light cycle. This circadian clock is governed by a central pacemaker, the suprachiasmatic nucleus (SCN) in the brain. However, peripheral circadian clocks or oscillators have been identified in most tissues. How the central and peripheral oscillators are synchronized is still being elucidated. Light is the main environmental cue that entrains the circadian clock. Under the absence of a light stimulus, the clock continues its oscillation in a free-running condition. In general, three functional compartments of the circadian clock are defined. The vertebrate retina contains endogenous clocks that control many aspects of retinal physiology, including retinal sensitivity to light, neurohormone synthesis (melatonin and dopamine), rod disk shedding, signalling pathways and gene expression. Neurons with putative local circadian rhythm generation are found among all the major neuron populations in the mammalian retina. In the mouse, clock genes and function are more localized to the inner retinal and ganglion cell layers. The photoreceptor, however, secrete melatonin which may still serve a an important circadian signal. The reception and transmission of the non-visual photic stimulus resides in a small subpopulation (1-3%) or retinal ganglion cells (RGC) that express the pigment melanopsin (Opn4) and are called intrisically photoreceptive RGC (ipRGC). Melanopsin peak absorption is at 420 nm and all the axons of the ipRGC reach the SCN. A common countermeasure for circadian re-entrainment utilizes blue-green light to entrain the circadian clock and mitigate the risk of fatigue and health and performance decrement due to circadian rhythm disruption. However, an effective countermeasure targeting the photoreceptor system requires that the basic circadian molecular machinery remains intact during spaceflight. We hypothesize that spaceflight may affect ip

  2. Photodynamic therapy: Biophysical mechanisms and molecular responses

    Science.gov (United States)

    Mitra, Soumya

    In photodynamic therapy (PDT), photochemical reactions induced by optical activation of sensitizer molecules cause destruction of the target tissue. In this thesis we present results of several related studies, which investigated the influence of photophysical properties and photobleaching mechanisms of sensitizers and oxygen-dependent tissue optical properties on PDT treatment efficacy. The bleaching mechanism of the sensitizer meso-tetra hydroxyphenyl chlorin (mTHPC) is examined indirectly using measurements of photochemical oxygen consumption during PDT irradiation of multicell tumor spheroids. Analysis of the results with a theoretical model of oxygen diffusion that incorporates the effects of sensitizer photobleaching shows that mTHPC is degraded via a singlet-oxygen (1O2)-mediated bleaching process. The analysis allows us to extract photophysical parameters of mTHPC which are used to account for its enhanced clinical photodynamic potency in comparison to that of Photofrin. Evaluation of the spatially-resolved fluorescence in confocal optical sections of intact spheroids during PDT irradiation allows for the direct experimental verification of mTHPC's 1O2-mediated bleaching mechanism. The technique is also used to investigate the complex bleaching kinetics of Photofrin. The results allow us to successfully reconcile apparently contradictory experimental observations and to confirm the predictions of a new theoretical model in which both 1O2 and excited triplet sensitizer molecules are allowed to contribute to photobleaching. Based on studies performed in tissue-simulating erythrocyte phantoms and in a murine tumor model in vivo, we present clinically relevant results which indicate that a shift toward increased hemoglobin-oxygen saturation due to improved tissue oxygenation reduces PDT treatment beam attenuation and may allow for more effective treatment of deeper lesions. Finally, we investigate the induction of the stress protein, heat shock protein 70 (HSP

  3. Splicing Regulation: A Molecular Device to Enhance Cancer Cell Adaptation

    Directory of Open Access Journals (Sweden)

    Vittoria Pagliarini

    2015-01-01

    Full Text Available Alternative splicing (AS represents a major resource for eukaryotic cells to expand the coding potential of their genomes and to finely regulate gene expression in response to both intra- and extracellular cues. Cancer cells exploit the flexible nature of the mechanisms controlling AS in order to increase the functional diversity of their proteome. By altering the balance of splice isoforms encoded by human genes or by promoting the expression of aberrant oncogenic splice variants, cancer cells enhance their ability to adapt to the adverse growth conditions of the tumoral microenvironment. Herein, we will review the most relevant cancer-related splicing events and the underlying regulatory mechanisms allowing tumour cells to rapidly adapt to the harsh conditions they may face during the occurrence and development of cancer.

  4. [Development of molecular targeted therapies in lung cancers].

    Science.gov (United States)

    Suda, Kenichi; Mitsudomi, Tetsuya

    2014-05-01

    Human cancers usually possess cumulative genetic aberrations. However, recent studies have revealed that the proliferation and survival of specific subsets of lung cancer depend on a few somatic mutation(s), so-called driver mutations. Representative driver mutations include the EGFR mutation and ALK translocation identified in about 40% and 3% of lung adenocarcinomas in Japan, respectively. These tumors are extremely sensitive to the respective tyrosine kinase inhibitors. This sensitivity has encouraged researchers and clinicians to explore novel driver mutations in lung cancers as future molecular targets. Driver mutations reported so far include the HER2 mutation, BRAF mutation, ROS1 translocation, RET translocation, and NTRK translocation in lung adenocarcinomas, and FGFR1 amplification, DDR2 mutation, and FGFR3 translocation in lung squamous cell carcinomas. However, despite initial dramatic responses, the acquisition of resistance to molecular targeted drugs is almost inevitable. Overcoming resistance to molecular targeted drugs, the key drugs at this time, is an urgent issue to improve the outcomes of lung cancer patients. PMID:24946519

  5. Non-invasive Optical Molecular Imaging for Cancer Detection

    Science.gov (United States)

    Luo, Zhen

    Cancer is a leading cause of death worldwide. It remains the second most common cause of death in the US, accounting for nearly 1 out of every 4 deaths. Improved fundamental understanding of molecular processes and pathways resulting in cancer development has catalyzed a shift towards molecular analysis of cancer using imaging technologies. It is expected that the non-invasive or minimally invasive molecular imaging analysis of cancer can significantly aid in improving the early detection of cancer and will result in reduced mortality and morbidity associated with the disease. The central hypothesis of the proposed research is that non-invasive imaging of changes in metabolic activity of individual cells, and extracellular pH within a tissue will improve early stage detection of cancer. The specific goals of this research project were to: (a) develop novel optical imaging probes to image changes in choline metabolism and tissue pH as a function of progression of cancer using clinically isolated tissue biopsies; (b) correlate changes in tissue extracellular pH and metabolic activity of tissues as a function of disease state using clinically isolated tissue biopsies; (c) provide fundamental understanding of relationship between tumor hypoxia, acidification of the extracellular space and altered cellular metabolism with progression of cancer. Three novel molecular imaging probes were developed to detect changes in choline and glucose metabolism and extracellular pH in model systems and clinically isolated cells and biopsies. Glucose uptake and metabolism was measured using a fluorescence analog of glucose, 2-NBDG (2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose), while choline metabolism was measured using a click chemistry analog of choline, propargyl choline, which can be in-situ labeled with a fluorophore Alexa-488 azide via a click chemistry reaction. Extracellular pH in tissue were measured by Alexa-647 labeled pHLIP (pH low insertion peptide

  6. Plasticity of Cancer Cell Invasion-Mechanisms and Implications for Therapy.

    Science.gov (United States)

    Te Boekhorst, V; Friedl, P

    2016-01-01

    Cancer cell migration is a plastic and adaptive process integrating cytoskeletal dynamics, cell-extracellular matrix and cell-cell adhesion, as well as tissue remodeling. In response to molecular and physical microenvironmental cues during metastatic dissemination, cancer cells exploit a versatile repertoire of invasion and dissemination strategies, including collective and single-cell migration programs. This diversity generates molecular and physical heterogeneity of migration mechanisms and metastatic routes, and provides a basis for adaptation in response to microenvironmental and therapeutic challenge. We here summarize how cytoskeletal dynamics, protease systems, cell-matrix and cell-cell adhesion pathways control cancer cell invasion programs, and how reciprocal interaction of tumor cells with the microenvironment contributes to plasticity of invasion and dissemination strategies. We discuss the potential and future implications of predicted "antimigration" therapies that target cytoskeletal dynamics, adhesion, and protease systems to interfere with metastatic dissemination, and the options for integrating antimigration therapy into the spectrum of targeted molecular therapies. PMID:27613134

  7. Research on the molecular scale material removal mechanism in chemical mechanical polishing

    Institute of Scientific and Technical Information of China (English)

    WANG YongGuang; ZHAO YongWu

    2008-01-01

    This paper investigates a novel molecular scale material removal mechanism in chemical mechanical polishing (CMP) by incorporating the order-of-magnitude calculations,particle adhesion force,defect of wafer,thickness of newly formed oxidizedlayer,and large deformation of pad/particle not discussed by previous analysis.The theoretical analysis and experimental data show that the indentation depth,scratching depth and polishing surface roughness are on the order of molecular scale or less.There.fore,this novel mechanism has gained the support from wide order-of- magnitude calculations and experimental data.In addition,with the decrease in the particle size,the molecular scale removal mechanism is plausibly one of the most promising removal mechanisms to clarify the CMP polishing process.The results are useful to substantiating the molecular-scale mechanism of the CMP material removal in addition to its underlying theoretical foundation.

  8. Molecular imaging in neuroendocrine tumors : Molecular uptake mechanisms and clinical results

    NARCIS (Netherlands)

    Koopmans, Klaas P.; Neels, Oliver N.; Kema, Ido P.; Elsinga, Philip H.; Links, Thera P.; de Vries, Elisabeth G. E.; Jager, Pieter L.

    2009-01-01

    Neuroendocrine tumors can originate almost everywhere in the body and consist of a great variety of subtypes. This paper focuses on molecular imaging methods using nuclear medicine techniques in neuroendocrine tumors, coupling molecular uptake mechanisms of radiotracers with clinical results. A non-

  9. Procathepsin D and cancer: From molecular biology to clinical applications

    OpenAIRE

    Vetvicka, Vaclav; Vashishta, Aruna; Saraswat-Ohri, Sujata; Vetvickova, Jana

    2010-01-01

    Procathepsin D (pCD) is overexpressed and secreted by cells of various tumor types including breast and lung carcinomas. pCD affects multiple features of tumor cells including proliferation, invasion, metastases and apoptosis. Several laboratories have previously shown that the mitogenic effect of pCD on cancer cells is mediated via its propeptide part (APpCD). However, the exact mechanism of how pCD affects cancer cells has not been identified. Recent observations have also revealed the poss...

  10. Molecular subtyping of breast cancer: opportunities for new therapeutic approaches.

    Science.gov (United States)

    Mullan, P B; Millikan, R C

    2007-12-01

    Evidence is accumulating that breast cancer is not one disease but many separate diseases. DNA microarray-based gene expression profiling has demonstrated subtypes with distinct phenotypic features and clinical responses. Prominent among the new subtypes is 'basal-like' breast cancer, one of the 'intrinsic' subtypes defined by negativity for the estrogen, progesterone, and HER2/neu receptors and positivity for cytokeratins-5/6. Focusing on basal-like breast cancer, we discuss how molecular technologies provide new chemotherapy targets, optimising treatment whilst sparing patients from unnecessary toxicity. Clinical trials are needed that incorporate long-term follow-up of patients with well-characterised tumour markers. Whilst the absence of an obvious dominant oncogene driving basal-like breast cancer and the lack of specific therapeutic agents are serious stumbling blocks, this review will highlight several promising therapeutic candidates currently under evaluation. Thus, new molecular technologies should provide a fundamental foundation for better understanding breast and other cancers which may be exploited to save lives. (Part of a Multi-author Review). PMID:17957336

  11. Molecular markers and targets for colorectal cancer prevention

    Institute of Scientific and Technical Information of China (English)

    Naveena B JANAKIRAM; Chinthalapally V RAO

    2008-01-01

    Colorectal cancer is the third most prevalent cancer in the world. If detected at an early stage, treatment often might lead to cure. As prevention is better than cure, epidemiological studies reveal that having a healthy diet often protects from pro-moting/developing cancer. An important consideration in evaluating new drugs and devices is determining whether a product can effectively treat a targeted disease. There are quite a number of biomarkers making their way into clinical trials and few are awaiting the preclinical efficacy and safety results to enter into clinical trials. Researchers are facing challenges in modifying trial design and defining the right control population, validating biomarker assays from the bio-logical and analytical perspective and using biomarker data as a guideline for decision making. In spite of following all guidelines, the results are disappointing from many of the large clinical trials. To avoid these disappointments, selection of biomarkers and its target drug needs to be evaluated in appropriate animal models for its toxicities and efficacies. The focus of this review is on the few of the potential molecular targets and their biomarkers in colorectal cancers. Strengths and limitations of biomarkers/surrogate endpoints are also discussed. Various pathways involved in tumor cells and the specific agents to target the altered molecular biomarkerin biomolecular pathwayare elucidated. Importance of emerging new platforms siRNAs and miRNAs technology for colorectal cancer therapeutics is reviewed.

  12. Telomerase promoter mutations in cancer: an emerging molecular biomarker?

    Science.gov (United States)

    Vinagre, João; Pinto, Vasco; Celestino, Ricardo; Reis, Marta; Pópulo, Helena; Boaventura, Paula; Melo, Miguel; Catarino, Telmo; Lima, Jorge; Lopes, José Manuel; Máximo, Valdemar; Sobrinho-Simões, Manuel; Soares, Paula

    2014-08-01

    Cell immortalization has been considered for a long time as a classic hallmark of cancer cells. Besides telomerase reactivation, such immortalization could be due to telomere maintenance through the "alternative mechanism of telomere lengthening" (ALT) but the mechanisms underlying both forms of reactivation remained elusive. Mutations in the coding region of telomerase gene are very rare in the cancer setting, despite being associated with some degenerative diseases. Recently, mutations in telomerase (TERT) gene promoter were found in sporadic and familial melanoma and subsequently in several cancer models, notably in gliomas, thyroid cancer and bladder cancer. The importance of these findings has been reinforced by the association of TERT mutations in some cancer types with tumour aggressiveness and patient survival. In the first part of this review, we summarize the data on the biology of telomeres and telomerase, available methodological approaches and non-neoplastic diseases associated with telomere dysfunction. In the second part, we review the information on telomerase expression and genetic alterations in the most relevant types of cancer (skin, thyroid, bladder and central nervous system) on record, and discuss the value of telomerase as a new biomarker with impact on the prognosis and survival of the patients and as a putative therapeutic target. PMID:25048572

  13. Molecular mechanisms of LRRK2 regulation

    Science.gov (United States)

    Webber, Philip Jeffrey

    Non-synonymous mutations in LRRK2 are the most common known cause of familial and sporadic Parkinson's disease (PD). The dominant inheritance of these mutations in familial PD suggests a gain-of-function mechanism. Increased kinase activity observed in the most common PD associated LRRK2 mutation G2019S suggests that kinase activity is central to disease. However, not all mutations associated with disease are reported to alter kinase activity and controversy exists in the literature about the effects of mutations appearing in the GTPase domain on kinase activity. The studies conducted as a part of this work aim to characterize the mechanisms that regulate LRRK2 kinase activity and the effects of mutations on enzymatic activity of LRRK2 protein. LRRK2 is a large protein with multiple predicted functional domains including two enzymatic domains in the same protein, the small ras-like GTPase domain and a serine-threonine protein kinase domain. Previous studies indicate that LRRK2 kinase is dependent on a functional GTPase domain and binding to GTP is required for kinase activity. Recent work detailed in this dissertation indicates a complex and reciprocal relationship between kinase and GTPase domains. LRRK2 kinase activity is dependent on adapting a homo-dimer that is augmented by PD mutations that increase LRRK2 kinase activity. Activated LRRK2 autophosphorylates the GTPase and c-terminus of Ras (COR) domains robustly. Phosphorylation of these domains is required for normal activity, as preventing autophosphorylation of these sites drastically lowers kinase activity and GTP binding while phosphorylation maintains baseline activity while still reducing GTP binding. Furthermore, we have developed antibodies specific to autophosphorylation residues that track with LRRK2 kinase activity in vitro. While no measurable activity was detected from treated LRRK2 in vivo, LRRK2 protein purified from brain tissue treated with inflammatory stimuli such as LPS, which increases

  14. Molecular mechanisms of alcohol associated pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Dahn; L; Clemens; Mark; A; Wells; Katrina; J; Schneider; Shailender; Singh

    2014-01-01

    Alcohol abuse is commonly associated with the development of both acute and chronic pancreatitis. Despite this close association, the fact that only a small percentage of human beings who abuse alcohol develop pancreatitis indicates that alcohol abuse alone is not sufficient to initiate clinical pancreatitis. This contention is further supported by the fact that administration of ethanol to experimental animals does not cause pancreatitis. Because of these findings, it is widely believed that ethanol sensitizes the pancreas to injury and additional factors trigger the development of overt pancreatitis. How ethanol sensitizes the pancreas to pancreatitis is not entirely known. Numerous studies have demonstrated that ethanol and its metabolites have a number of deleterious effects on acinar cells. Important acinar cells properties that are affected by ethanol include: calcium signaling, secretion of zymogens, autophagy, cellular regeneration, the unfolded protein response, and mitochondrial membrane integrity. In addition to the actions of ethanol on acinar cells, it is apparent that ethanol also affects pancreatic stellatecells. Pancreatic stellate cells have a critical role in normal tissue repair and the pathologic fibrotic response. Given that ethanol and its metabolites affect so many pancreatic functions, and that all of these effects occur simultaneously, it is likely that none of these effects is "THE" effect. Instead, it is most likely that the cumulative effect of ethanol on the pancreas predisposes the organ to pancreatitis. The focus of this article is to highlight some of the important mechanisms by which ethanol alters pancreatic functions and may predispose the pancreas to disease.

  15. Substrate binding and catalytic mechanism in phospholipase C from Bacillus cereus. a molecular mechanics and molecular dynamics study

    DEFF Research Database (Denmark)

    da Graça Thrige, D; Buur, J R; Jørgensen, Flemming Steen

    1997-01-01

    For the first time a consistent catalytic mechanism of phospholipase C from Bacillus cereus is reported based on molecular mechanics calculations. We have identified the position of the nucleophilic water molecule, which is directly involved in the hydrolysis of the natural substrate phosphatidyl...

  16. MicroRNAs as molecular markers in lung cancer

    Directory of Open Access Journals (Sweden)

    Javier Silva

    2013-10-01

    Full Text Available Lung cancer is the most common cause of cancer death in the western world for both men and women. Lung cancer appears to be a perfect candidate for a screening program, since it is the number one cancer killer, it has a long preclinical phase, curative treatment for the minority of patients who are diagnosed early and a target population at risk (smokers and it is also a major economic burden. The earliest approaches to identifying cancer markers were based on preliminary clinical or pathological observations, although molecular biology is a strong candidate for occupying a place among the set of methods. In search of markers, several alterations, such as mutations, loss of heterozygosity, microsatellite instability, DNA methylation, mitochondrial DNA mutations, viral DNA, modified expression of mRNA, miRNA and proteins, and structurally altered proteins have all been analysed. MicroRNAs (miRNA are small RNA molecules, about 19-25 nucleotides long and encoded in genomes of plants, animals, fungi and viruses. It has been reported that miRNAs may have multiple functions in lung development and that aberrant expression of miRNAs could induce lung tumorigenesis. We review here the role of miRNAs in lung tumorigenesis and also as a novel type of biomarker.-----------------------------------Cite this article as:Silva J, Garcia V, Lopez-Gonzalez A, Provencio M. MicroRNAs as molecular markers in lung cancer. Int J Cancer Ther Oncol 2013;1(1:010111. DOI: http://dx.doi.org/10.14319/ijcto.0101.11

  17. Immunophenotyping invasive breast cancer: paving the road for molecular imaging

    Directory of Open Access Journals (Sweden)

    Vermeulen Jeroen F

    2012-06-01

    Full Text Available Abstract Background Mammographic population screening in The Netherlands has increased the number of breast cancer patients with small and non-palpable breast tumors. Nevertheless, mammography is not ultimately sensitive and specific for distinct subtypes. Molecular imaging with targeted tracers might increase specificity and sensitivity of detection. Because development of new tracers is labor-intensive and costly, we searched for the smallest panel of tumor membrane markers that would allow detection of the wide spectrum of invasive breast cancers. Methods Tissue microarrays containing 483 invasive breast cancers were stained by immunohistochemistry for a selected set of membrane proteins known to be expressed in breast cancer. Results The combination of highly tumor-specific markers glucose transporter 1 (GLUT1, epidermal growth factor receptor (EGFR, insulin-like growth factor-1 receptor (IGF1-R, human epidermal growth factor receptor 2 (HER2, hepatocyte growth factor receptor (MET, and carbonic anhydrase 9 (CAIX 'detected' 45.5% of tumors, especially basal/triple negative and HER2-driven ductal cancers. Addition of markers with a 2-fold tumor-to-normal ratio increased the detection rate to 98%. Including only markers with >3 fold tumor-to-normal ratio (CD44v6 resulted in an 80% detection rate. The detection rate of the panel containing both tumor-specific and less tumor-specific markers was not dependent on age, tumor grade, tumor size, or lymph node status. Conclusions In search of the minimal panel of targeted probes needed for the highest possible detection rate, we showed that 80% of all breast cancers express at least one of a panel of membrane markers (CD44v6, GLUT1, EGFR, HER2, and IGF1-R that may therefore be suitable for molecular imaging strategies. This study thereby serves as a starting point for further development of a set of antibody-based optical tracers with a high breast cancer detection rate.

  18. Immunophenotyping invasive breast cancer: paving the road for molecular imaging

    International Nuclear Information System (INIS)

    Mammographic population screening in The Netherlands has increased the number of breast cancer patients with small and non-palpable breast tumors. Nevertheless, mammography is not ultimately sensitive and specific for distinct subtypes. Molecular imaging with targeted tracers might increase specificity and sensitivity of detection. Because development of new tracers is labor-intensive and costly, we searched for the smallest panel of tumor membrane markers that would allow detection of the wide spectrum of invasive breast cancers. Tissue microarrays containing 483 invasive breast cancers were stained by immunohistochemistry for a selected set of membrane proteins known to be expressed in breast cancer. The combination of highly tumor-specific markers glucose transporter 1 (GLUT1), epidermal growth factor receptor (EGFR), insulin-like growth factor-1 receptor (IGF1-R), human epidermal growth factor receptor 2 (HER2), hepatocyte growth factor receptor (MET), and carbonic anhydrase 9 (CAIX) 'detected' 45.5% of tumors, especially basal/triple negative and HER2-driven ductal cancers. Addition of markers with a 2-fold tumor-to-normal ratio increased the detection rate to 98%. Including only markers with >3 fold tumor-to-normal ratio (CD44v6) resulted in an 80% detection rate. The detection rate of the panel containing both tumor-specific and less tumor-specific markers was not dependent on age, tumor grade, tumor size, or lymph node status. In search of the minimal panel of targeted probes needed for the highest possible detection rate, we showed that 80% of all breast cancers express at least one of a panel of membrane markers (CD44v6, GLUT1, EGFR, HER2, and IGF1-R) that may therefore be suitable for molecular imaging strategies. This study thereby serves as a starting point for further development of a set of antibody-based optical tracers with a high breast cancer detection rate

  19. Molecular targets of aspirin and cancer prevention.

    Science.gov (United States)

    Alfonso, L; Ai, G; Spitale, R C; Bhat, G J

    2014-07-01

    Salicylates from plant sources have been used for centuries by different cultures to treat a variety of ailments such as inflammation, fever and pain. A chemical derivative of salicylic acid, aspirin, was synthesised and mass produced by the end of the 19th century and is one of the most widely used drugs in the world. Its cardioprotective properties are well established; however, recent evidence shows that it can also act as a chemopreventive agent. Its antithrombotic and anti-inflammatory actions occur through the inhibition of cyclooxygenases. The precise mechanisms leading to its anticancer effects are not clearly established, although multiple mechanisms affecting enzyme activity, transcription factors, cellular signalling and mitochondrial functions have been proposed. This review presents a brief account of the major COX-dependent and independent pathways described in connection with aspirin's anticancer effects. Aspirin's unique ability to acetylate biomolecules besides COX has not been thoroughly investigated nor have all the targets of its primary metabolite, salicylic acid been identified. Recent reports on the ability of aspirin to acetylate multiple cellular proteins warrant a comprehensive study to investigate the role of this posttranslational modification in its anticancer effects. In this review, we also raise the intriguing possibility that aspirin may interact and acetylate cellular molecules such as RNA, and metabolites such as CoA, leading to a change in their function. Research in this area will provide a greater understanding of the mechanisms of action of this drug. PMID:24874482

  20. Lactobacilli as multifaceted probiotics with poorly disclosed molecular mechanisms

    OpenAIRE

    Turpin, Williams; Humblot, Christèle; M. Thomas; Guyot, Jean-Pierre

    2010-01-01

    Lactic acid bacteria and more particularly lactobacilli have been used for the production of fermented foods for centuries. Several lactobacilli have been recognized as probiotics due to their wide range of health-promoting effects in humans. However, little is known about the molecular mechanisms underpinning their probiotic functions. Here we reviewed the main beneficial effects of lactobacilli and discussed, when the information is available, the molecular machinery involved in their probi...

  1. Growth-inhibitory Effects of Curcumin on Ovary Cancer Cells and Its Mechanisms

    Institute of Scientific and Technical Information of China (English)

    郑丽端; 童强松; 吴翠环

    2004-01-01

    Summary: To study the growth-inhibitory ettects ot curcumin on human ovary cancer A2780 cells in vitro and its molecular mechanisms, the growth inhibition rates of A2780 cancer cells, after being treated with 10 μmol/L-50 μmol/L curcumin for 6-24 h, were examined by MTT method. The morphological changes of cancer cells were observed under inversion microscopy. Cellular apoptotic rates were determined by using TUNEL. The protein expression levels of bcl-2, p53 and MDM2 in cancer cells were examined by SP immunohistochemistry. After being treated by various concentrations of curcumin, the growth of cancer cells was inhibited significantly. Some cancer cells presented characteristic morphological changes of apoptosis. The rates of apoptosis were 6.41% -28.48% (P<0.01). The expression of bcl-2 and p53 was decreased, which depended on the action time (P<0.01). There were no obvious changes in MDM2 expression. It was concluded that curcumin could significantly inhibit the growth of ovary cancer cells. The induction of apoptosis by down-regulating the expression of bcl-2 and p53 was probably one of its molecular mechanisms.

  2. Molecular Theory of the Living Cell Concepts, Molecular Mechanisms, and Biomedical Applications

    CERN Document Server

    Ji, Sungchul

    2012-01-01

    This book presents a comprehensive molecular theory of the living cell based on over thirty concepts, principles and laws imported from thermodynamics, statistical mechanics, quantum mechanics, chemical kinetics, informatics, computer science, linguistics, semiotics, and philosophy. The author formulates physically, chemically and enzymologically realistic molecular mechanisms to account for the basic living processes such as ligand-receptor interactions, protein folding, single-molecule enzymic catalysis, force-generating mechanisms in molecular motors, signal transduction, regulation of the genome-wide RNA metabolism, morphogenesis, the micro-macro coupling in coordination dynamics, the origin of life, and the mechanisms of biological evolution itself. Possible solutions to basic and practical problems facing contemporary biology and biomedical sciences have been suggested, including pharmacotheragnostics and personalized medicine.

  3. Mini-review: Molecular mechanisms of antifouling compounds

    KAUST Repository

    Qian, Pei-Yuan

    2013-04-01

    Various antifouling (AF) coatings have been developed to protect submerged surfaces by deterring the settlement of the colonizing stages of fouling organisms. A review of the literature shows that effective AF compounds with specific targets are ones often considered non-toxic. Such compounds act variously on ion channels, quorum sensing systems, neurotransmitters, production/release of adhesive, and specific enzymes that regulate energy production or primary metabolism. In contrast, AF compounds with general targets may or may not act through toxic mechanisms. These compounds affect a variety of biological activities including algal photosynthesis, energy production, stress responses, genotoxic damage, immunosuppressed protein expression, oxidation, neurotransmission, surface chemistry, the formation of biofilms, and adhesive production/release. Among all the targets, adhesive production/release is the most common, possibly due to a more extensive research effort in this area. Overall, the specific molecular targets and the molecular mechanisms of most AF compounds have not been identified. Thus, the information available is insufficient to draw firm conclusions about the types of molecular targets to be used as sensitive biomarkers for future design and screening of compounds with AF potential. In this review, the relevant advantages and disadvantages of the molecular tools available for studying the molecular targets of AF compounds are highlighted briefly and the molecular mechanisms of the AF compounds, which are largely a source of speculation in the literature, are discussed. © 2013 Copyright Taylor and Francis Group, LLC.

  4. AN EPIDEMIOLOGY AND MOLECULAR GENETIC STUDY ON BREAST CANCER SUSCEPTIBILITY

    Institute of Scientific and Technical Information of China (English)

    贾卫华; 王继先; 李本孝; 李征

    2000-01-01

    Objectives. To investigate the genetic susceptibility for breast cancer of Chinese, a hospital-based case-control study, pedigree survey and molecular genetic study were conducted. Methods. Logistic regression model and stratification methods were used in the risk factors analysis. Li-Mantel art and Falconer methods were used to analyze the segregation ratio and heritability. Polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis were used to detect AI, G-banding technique was used to detect the chromosome aberration of peripheral blood lymphocyte. Results. Family history of breast cancer is related to enhanced breast cancer risk significartly, OR is 3.905 ( 95 % CI = 1.079 ~ 14.13), and it widely interacts with other risk factors. Accumulative incidence of breast cancer in first degree relatives is 9.99%, which is larger than that in second, third degree and non-blood relatives. Segregation ratio is 0.021, heritability among first degree relatives is 35.6 ± 5.8%. Frequencies of LOH at BRCA1 and BRCA2 loci in sporadic breast cancer are 6.12% and 5.77% respectively. In the sibs, both of them show LOH at D13S173 locus, and high frequencies of chromosome aberrations were observed. Conclusions. Genetic susceptibility contributes to breast cancer occurrence of Chinese, and its racial variation may be one of the important reasons for the large difference of incidence between western and eastern countries.

  5. AN EPIDEMIOLOGY AND MOLECULAR GENETIC STUDY ON BREAST CANCER SUSCEPTIBILITY

    Institute of Scientific and Technical Information of China (English)

    贾卫华; 王继先; 李本孝; 李征

    2000-01-01

    Obieaites. To investigate the genetic susceptibility for breast cancer of Chinese, a hospital-besed case-control study, pedigree survey and molecular genetic study were conducted. Methods. Logistic regression model and stratification methods were used in the risk factors analysis. Li-Mantel-Gart and Falconer methods were used to analyze the segregation ratio and heritability. Polymemse chain reaction (PCR) and polyacrylamide gel electrophoresis were used to detect AI, G-banding technique was used to detect the chromosome aberration of peripheral blood lymphocyte. Results. Family history of breast cancer is related to enhanced breast cancer risk significantly, OR is 3.905(95% CI = 1.079—14.13), and it widely interacts with other risk factors. Accumulative incidence of breast cancer in first degree relatives is 9.99%, which is larger than that in second, third degree and non-blnod relatives. Segregation ratio is 0.021, heritability among first degree relatives is 35.6 ± 5.8%. Frequencies of LDH at BRCA1 and BRCA2 loci in sporadic breast cancer are 6.12% and 5.77% respectively. In the sibs, both of them show LOH at D13S173 locus, and high frequencies of chromosome abermtions were observed.Condusions. Genetic susceptibility contributes to breast cancer occurrence of Chinese, and its racial variation may be one of the important reasons for the large difference of incidence between western and eastern countries.

  6. Reaction Mechanism of Mycobacterium Tuberculosis Glutamine Synthetase Using Quantum Mechanics/Molecular Mechanics Calculations.

    Science.gov (United States)

    Moreira, Cátia; Ramos, Maria J; Fernandes, Pedro Alexandrino

    2016-06-27

    This paper is devoted to the understanding of the reaction mechanism of mycobacterium tuberculosis glutamine synthetase (mtGS) with atomic detail, using computational quantum mechanics/molecular mechanics (QM/MM) methods at the ONIOM M06-D3/6-311++G(2d,2p):ff99SB//B3LYP/6-31G(d):ff99SB level of theory. The complete reaction undergoes a three-step mechanism: the spontaneous transfer of phosphate from ATP to glutamate upon ammonium binding (ammonium quickly loses a proton to Asp54), the attack of ammonia on phosphorylated glutamate (yielding protonated glutamine), and the deprotonation of glutamine by the leaving phosphate. This exothermic reaction has an activation free energy of 21.5 kcal mol(-1) , which is consistent with that described for Escherichia coli glutamine synthetase (15-17 kcal mol(-1) ). The participating active site residues have been identified and their role and energy contributions clarified. This study provides an insightful atomic description of the biosynthetic reaction that takes place in this enzyme, opening doors for more accurate studies for developing new anti-tuberculosis therapies.

  7. Reaction Mechanism of Mycobacterium Tuberculosis Glutamine Synthetase Using Quantum Mechanics/Molecular Mechanics Calculations.

    Science.gov (United States)

    Moreira, Cátia; Ramos, Maria J; Fernandes, Pedro Alexandrino

    2016-06-27

    This paper is devoted to the understanding of the reaction mechanism of mycobacterium tuberculosis glutamine synthetase (mtGS) with atomic detail, using computational quantum mechanics/molecular mechanics (QM/MM) methods at the ONIOM M06-D3/6-311++G(2d,2p):ff99SB//B3LYP/6-31G(d):ff99SB level of theory. The complete reaction undergoes a three-step mechanism: the spontaneous transfer of phosphate from ATP to glutamate upon ammonium binding (ammonium quickly loses a proton to Asp54), the attack of ammonia on phosphorylated glutamate (yielding protonated glutamine), and the deprotonation of glutamine by the leaving phosphate. This exothermic reaction has an activation free energy of 21.5 kcal mol(-1) , which is consistent with that described for Escherichia coli glutamine synthetase (15-17 kcal mol(-1) ). The participating active site residues have been identified and their role and energy contributions clarified. This study provides an insightful atomic description of the biosynthetic reaction that takes place in this enzyme, opening doors for more accurate studies for developing new anti-tuberculosis therapies. PMID:27225077

  8. Clinical implications of the intrinsic molecular subtypes of breast cancer.

    Science.gov (United States)

    Prat, Aleix; Pineda, Estela; Adamo, Barbara; Galván, Patricia; Fernández, Aranzazu; Gaba, Lydia; Díez, Marc; Viladot, Margarita; Arance, Ana; Muñoz, Montserrat

    2015-11-01

    Gene-expression profiling has had a considerable impact on our understanding of breast cancer biology. During the last 15 years, 5 intrinsic molecular subtypes of breast cancer (Luminal A, Luminal B, HER2-enriched, Basal-like and Claudin-low) have been identified and intensively studied. In this review, we will focus on the current and future clinical implications of the intrinsic molecular subtypes beyond the current pathological-based classification endorsed by the 2013 St. Gallen Consensus Recommendations. Within hormone receptor-positive and HER2-negative early breast cancer, the Luminal A and B subtypes predict 10-year outcome regardless of systemic treatment administered as well as residual risk of distant recurrence after 5 years of endocrine therapy. Within clinically HER2-positive disease, the 4 main intrinsic subtypes can be identified and dominate the biological and clinical phenotype. From a clinical perspective, patients with HER2+/HER2-enriched disease seem to benefit the most from neoadjuvant trastuzumab, or dual HER2 blockade with trastuzumab/lapatinib, in combination with chemotherapy, and patients with HER2+/Luminal A disease seem to have a relative better outcome compared to the other subtypes. Finally, within triple-negative breast cancer (TNBC), the Basal-like disease predominates (70-80%) and, from a biological perspective, should be considered a cancer-type by itself. Importantly, the distinction between Basal-like versus non-Basal-like within TNBC might predict survival following (neo)adjvuvant multi-agent chemotherapy, bevacizumab benefit in the neoadjuvant setting (CALGB40603), and docetaxel vs. carboplatin benefit in first-line metastatic disease (TNT study). Overall, this data suggests that intrinsic molecular profiling provides clinically relevant information beyond current pathology-based classifications.

  9. Molecular Targeted Therapies Using Botanicals for Prostate Cancer Chemoprevention

    OpenAIRE

    Kumar, Nagi; Chornokur, Ganna

    2012-01-01

    In spite of the large number of botanicals demonstrating promise as potential cancer chemopreventive agents, most have failed to prove effectiveness in clinical trials. Critical requirements for moving botanical agents to recommendation for clinical use include adopting a systematic, molecular-target based approach and utilizing the same ethical and rigorous methods that are used to evaluate other pharmacological agents. Preliminary data on a mechanistic rationale for chemoprevention activity...

  10. Status and Advances of RGD Molecular Imaging in Lung Cancer

    Directory of Open Access Journals (Sweden)

    Ning YUE

    2014-12-01

    Full Text Available Lung cancer has been one of the most common and the highest mortality rates malignant tumors at home and abroad. Sustained angiogenesis was not only the characteristic of malignant tumors, but also the foundation of tumor proliferation, invasion, recurrence and metastasis, it was also one of the hot spots of treatments in lung cancer biology currently. Integrins played an important part in tumor angiogenesis. Arg-Gly-Asp (RGD peptides could combine with integrins specifically, and the application of radionuclide-labeled RGD molecular probes enabled imaging of tumor blood vessels to reflect its changes. The lung cancer imaging of RGD peptides at home and abroad in recent years was reviewed in this article.

  11. Multifunctional Gold Nanostars for Molecular Imaging and Cancer Therapy

    Science.gov (United States)

    Liu, Yang; Yuan, Hsiangkuo; Fales, Andrew; Register, Janna; Vo-Dinh, Tuan

    2015-08-01

    Plasmonics-active gold nanoparticles offer excellent potential in molecular imaging and cancer therapy. Among them, gold nanostars (AuNS) exhibit cross-platform flexibility as multimodal contrast agents for macroscopic X-ray computer tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), as well as nanoprobes for photoacoustic tomography (PAT), two-photon photoluminescence (TPL) and surface-enhanced Raman spectroscopy (SERS). Their surfactant-free surface enables versatile functionalization to enhance cancer targeting, and allow triggered drug release. AuNS can also be used as an efficient platform for drug carrying, photothermal therapy, and photodynamic therapy. This review paper presents the latest progress regarding AuNS as a promising nanoplatform for cancer nanotheranostics. Future research directions with AuNS for biomedical applications will also be discussed.

  12. Mechanical Characterization of Breast Tissue Constituents for Cancer Assessment

    OpenAIRE

    Zaeimdar, Shima

    2014-01-01

    Breast elastography is a method of cancer detection that uses the response of soft tissue to deformations, leading to discovery of abnormalities. The methods of Clinical Breast Examination and Breast Self-Examination are based primarily on stiffness and, hence, on the mechanics of tissue constituents examined by palpation (Goodson, 1996). However, little is known about the mechanical characteristics of breast tissue under compression and the contribution of tissue mechanics to breast cancer d...

  13. Environmental effects on molecular biomarkers expression in pancreatic and brain cancer

    Science.gov (United States)

    Mensah, Lawrence; Mallidi, Srivalleesha; Massodi, Iqbal; Anbil, Sriram; Mai, Zhiming; Hasan, Tayyaba

    2013-03-01

    A complete understanding of the biological mechanisms regulating devastating disease such as cancer remains elusive. Pancreatic and brain cancers are primary among the cancer types with poor prognosis. Molecular biomarkers have emerged as group of proteins that are preferentially overexpressed in cancers and with a key role in driving disease progression and resistance to chemotherapy. The epidermal growth factor receptor (EGFR), a cell proliferative biomarker is particularly highly expressed in most cancers including brain and pancreatic cancers. The ability of EGFR to sustain prolong cell proliferation is augmented by biomarkers such as Bax, Bcl-XL and Bcl-2, proteins regulating the apoptotic process. To better understand the role and effect of the microenvironment on these biomarkers in pancreatic cancer (PaCa); we analysed two pancreatic tumor lines (AsPc-1 and MiaPaCa-2) in 2D, 3D in-vitro cultures and in orthotopic tumors at different growth stages. We also investigated in patient derived glioblastoma (GBM) tumor cultures, the ability to utilize the EGFR expression to specifically deliver photosensitizer to the cells for photodynamic therapy. Overall, our results suggest that (1) microenvironment changes affect biomarker expression; thereby it is critical to understand these effects prior to designing combination therapies and (2) EGFR expression in tumor cells indeed could serve as a reliable and a robust biomarker that could be used to design targeted and image-guided photodynamic therapy.

  14. Molecular characterization of the stomach microbiota in patients with gastric cancer and controls

    Energy Technology Data Exchange (ETDEWEB)

    Dicksved, J.; Lindberg, M.; Rosenquist, M.; Enroth, H.; Jansson, J.K.; Engstrand, L.

    2009-01-15

    Persistent infection of the gastric mucosa by Helicobacter pylori, can initiate an inflammatory cascade that progresses into atrophic gastritis, a condition associated with reduced capacity for secretion of gastric acid and an increased risk in developing gastric cancer. The role of H. pylori as an initiator of inflammation is evident but the mechanism for development into gastric cancer has not yet been proven. A reduced capacity for gastric acid secretion allows survival and proliferation of other microbes that normally are killed by the acidic environment. It has been postulated that some of these species may be involved in the development of gastric cancer, however their identities are poorly defined. In this study, the gastric microbiota from ten patients with gastric cancer was characterized and compared with five dyspeptic controls using the molecular profiling approach, terminal-restriction fragment length polymorphism (T-RFLP), in combination with 16S rRNA gene cloning and sequencing. T-RFLP analysis revealed a complex bacterial community in the cancer patients that was not significantly different from the controls. Sequencing of 140 clones revealed 102 phylotypes, with representatives from five bacterial phyla (Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria). The data revealed a relatively low abundance of H. pylori and showed that the gastric cancer microbiota was instead dominated by different species of the genera Streptococcus, Lactobacillus, Veillonella and Prevotella. The respective role of these species in development of gastric cancer remains to be determined.

  15. Molecular Classification of Gastric Cancer: A new paradigm

    Science.gov (United States)

    Shah, Manish A.; Khanin, Raya; Tang, Laura; Janjigian, Yelena Y.; Klimstra, David S.; Gerdes, Hans; Kelsen, David P.

    2011-01-01

    Purpose Gastric cancer may be subdivided into three distinct subtypes –proximal, diffuse, and distal gastric cancer– based on histopathologic and anatomic criteria. Each subtype is associated with unique epidemiology. Our aim is to test the hypothesis that these distinct gastric cancer subtypes may also be distinguished by gene expression analysis. Experimental Design Patients with localized gastric adenocarcinoma being screened for a phase II preoperative clinical trial (NCI 5917) underwent endoscopic biopsy for fresh tumor procurement. 4–6 targeted biopsies of the primary tumor were obtained. Macrodissection was performed to ensure >80% carcinoma in the sample. HG-U133A GeneChip (Affymetrix) was used for cDNA expression analysis, and all arrays were processed and analyzed using the Bioconductor R-package. Results Between November 2003 and January 2006, 57 patients were screened to identify 36 patients with localized gastric cancer who had adequate RNA for expression analysis. Using supervised analysis, we built a classifier to distinguish the three gastric cancer subtypes, successfully classifying each into tightly grouped clusters. Leave-one-out cross validation error was 0.14, suggesting that >85% of samples were classified correctly. Gene set analysis with the False Discovery Rate set at 0.25 identified several pathways that were differentially regulated when comparing each gastric cancer subtype to adjacent normal stomach. Conclusions Subtypes of gastric cancer that have epidemiologic and histologic distinction are also distinguished by gene expression data. These preliminary data suggest a new classification of gastric cancer with implications for improving our understanding of disease biology and identification of unique molecular drivers for each gastric cancer subtype. PMID:21430069

  16. Potential Anti-Cancer Activities and Mechanisms of Costunolide and Dehydrocostuslactone

    Directory of Open Access Journals (Sweden)

    Xuejing Lin

    2015-05-01

    Full Text Available Costunolide (CE and dehydrocostuslactone (DE are derived from many species of medicinal plants, such as Saussurea lappa Decne and Laurus nobilis L. They have been reported for their wide spectrum of biological effects, including anti-inflammatory, anticancer, antiviral, antimicrobial, antifungal, antioxidant, antidiabetic, antiulcer, and anthelmintic activities. In recent years, they have caused extensive interest in researchers due to their potential anti-cancer activities for various types of cancer, and their anti-cancer mechanisms, including causing cell cycle arrest, inducing apoptosis and differentiation, promoting the aggregation of microtubule protein, inhibiting the activity of telomerase, inhibiting metastasis and invasion, reversing multidrug resistance, restraining angiogenesis has been studied. This review will summarize anti-cancer activities and associated molecular mechanisms of these two compounds for the purpose of promoting their research and application.

  17. Roles of Ubiquitination and SUMOylation on Prostate Cancer: Mechanisms and Clinical Implications

    Directory of Open Access Journals (Sweden)

    Zhenbang Chen

    2015-02-01

    Full Text Available The initiation and progression of human prostate cancer are highly associated with aberrant dysregulations of tumor suppressors and proto-oncogenes. Despite that deletions and mutations of tumor suppressors and aberrant elevations of oncogenes at the genetic level are reported to cause cancers, emerging evidence has revealed that cancer progression is largely regulated by posttranslational modifications (PTMs and epigenetic alterations. PTMs play critical roles in gene regulation, cellular functions, tissue development, diseases, malignant progression and drug resistance. Recent discoveries demonstrate that ubiquitination and SUMOylation are complicated but highly-regulated PTMs, and make essential contributions to diseases and cancers by regulation of key factors and signaling pathways. Ubiquitination and SUMOylation pathways can be differentially modulated under various stimuli or stresses in order to produce the sustained oncogenic potentials. In this review, we discuss some new insights about molecular mechanisms on ubiquitination and SUMOylation, their associations with diseases, oncogenic impact on prostate cancer (PCa and clinical implications for PCa treatment.

  18. Probing molecular mechanisms of the Hsp90 chaperone: biophysical modeling identifies key regulators of functional dynamics.

    Directory of Open Access Journals (Sweden)

    Anshuman Dixit

    Full Text Available Deciphering functional mechanisms of the Hsp90 chaperone machinery is an important objective in cancer biology aiming to facilitate discovery of targeted anti-cancer therapies. Despite significant advances in understanding structure and function of molecular chaperones, organizing molecular principles that control the relationship between conformational diversity and functional mechanisms of the Hsp90 activity lack a sufficient quantitative characterization. We combined molecular dynamics simulations, principal component analysis, the energy landscape model and structure-functional analysis of Hsp90 regulatory interactions to systematically investigate functional dynamics of the molecular chaperone. This approach has identified a network of conserved regions common to the Hsp90 chaperones that could play a universal role in coordinating functional dynamics, principal collective motions and allosteric signaling of Hsp90. We have found that these functional motifs may be utilized by the molecular chaperone machinery to act collectively as central regulators of Hsp90 dynamics and activity, including the inter-domain communications, control of ATP hydrolysis, and protein client binding. These findings have provided support to a long-standing assertion that allosteric regulation and catalysis may have emerged via common evolutionary routes. The interaction networks regulating functional motions of Hsp90 may be determined by the inherent structural architecture of the molecular chaperone. At the same time, the thermodynamics-based "conformational selection" of functional states is likely to be activated based on the nature of the binding partner. This mechanistic model of Hsp90 dynamics and function is consistent with the notion that allosteric networks orchestrating cooperative protein motions can be formed by evolutionary conserved and sparsely connected residue clusters. Hence, allosteric signaling through a small network of distantly connected

  19. Topoisomerase I and II inhibitors: chemical structure, mechanisms of action and role in cancer chemotherapy

    Science.gov (United States)

    Dezhenkova, L. G.; Tsvetkov, V. B.; Shtil, A. A.

    2014-01-01

    The review summarizes and analyzes recent published data on topoisomerase I and II inhibitors as potential antitumour agents. Functions and the mechanism of action of topoisomerases are considered. The molecular mechanism of interactions between low-molecular-weight compounds and these proteins is discussed. Topoisomerase inhibitors belonging to different classes of chemical compounds are systematically covered. Assays for the inhibition of topoisomerases and the possibilities of using the computer-aided modelling for the rational design of novel drugs for cancer chemotherapy are presented. The bibliography includes 127 references.

  20. Appraisal of progenitor markers in the context of molecular classification of breast cancers

    OpenAIRE

    Haviv, Izhak

    2011-01-01

    Clinical management of breast cancer relies on case stratification, which increasingly employs molecular markers. The motivation behind delineating breast epithelial differentiation is to better target cancer cases through innate sensitivities bequeathed to the cancer from its normal progenitor state. A combination of histopathological and molecular classification of breast cancer cases suggests a role for progenitors in particular breast cancer cases. Although a remarkable fraction of the re...

  1. Molecular targets for the treatment of pancreatic cancer: Clinical and experimental studies

    OpenAIRE

    Matsuoka, Tasuku; Yashiro, Masakazu

    2016-01-01

    Pancreatic cancer is the fourth most common cause of cancer deaths worldwide. Although recent therapeutic developments for patients with pancreatic cancer have provided survival benefits, the outcomes for patients with pancreatic cancer remain unsatisfactory. Molecularly targeted cancer therapy has advanced in the past decade with the use of a number of pathways as candidates of therapeutic targets. This review summarizes the molecular features of this refractory disease while focusing on the...

  2. Molecular imaging of prostate cancer: translating molecular biology approaches into the clinical realm

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, Hebert Alberto; Sala, Evis; Hricak, Hedvig [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Grimm, Jan [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Program in Molecular Pharmacology and Chemistry, Memorial Sloan Kettering Cancer Center, New York (United States); Donati, Olivio F. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)

    2015-05-01

    The epidemiology of prostate cancer has dramatically changed since the introduction of prostate-specific antigen (PSA) screening in the 1980's. Most prostate cancers today are detected at early stages of the disease and are considered 'indolent'; however, some patients' prostate cancers demonstrate a more aggressive behaviour which leads to rapid progression and death. Increasing understanding of the biology underlying the heterogeneity that characterises this disease has led to a continuously evolving role of imaging in the management of prostate cancer. Functional and metabolic imaging techniques are gaining importance as the impact on the therapeutic paradigm has shifted from structural tumour detection alone to distinguishing patients with indolent tumours that can be managed conservatively (e.g., by active surveillance) from patients with more aggressive tumours that may require definitive treatment with surgery or radiation. In this review, we discuss advanced imaging techniques that allow direct visualisation of molecular interactions relevant to prostate cancer and their potential for translation to the clinical setting in the near future. The potential use of imaging to follow molecular events during drug therapy as well as the use of imaging agents for therapeutic purposes will also be discussed. (orig.)

  3. [Transforming growth factor beta-1: structure, function, and regulation mechanisms in cancer].

    Science.gov (United States)

    Peralta-Zaragoza, O; Lagunas-Martínez, A; Madrid-Marina, V

    2001-01-01

    Transforming growth factor beta-1 (TGF-beta 1) is produced by several cell lineages such as lymphocytes, macrophages, and dendritic cells, and its expression serves in both autocrine and paracrine modes to control the differentiation, proliferation, and state of activation of these and other cells. In general, TGF-beta 1 has pleiotropic properties on the immune response during the development of infection diseases and cancer; however, the mechanisms of action and regulation of gene expression of this cytokine are poorly understood, in this review, the biological properties and the molecular mechanisms that regulate TGF-beta 1 gene expression are described, to understand the role of this cytokine in growth and cell differentiation. The knowledge of molecular mechanisms of gene expression of TGF-beta 1 may serve to develop new cancer therapies. The English version of this paper is available at: http://www.insp.mx/salud/index.html PMID:11547595

  4. Molecular basis of the potential of mesalazine to prevent colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Carmine Stolfi; Roberto Pellegrini; Eleonora Franzè; Francesco Pallone; Giovanni Monteleone

    2008-01-01

    Patients with ulcerative colitis (UC) and Crohn's disease (CD) are at increased risk for developing colorectal cancer (CRC), and this is believed to be a result of chronic inflammation. Although conclusive evidence is still missing, both epidemiological and experimental observations suggest that certain drugs used to treat inflammation, such as mesalazine,can reduce the incidence of colitis-associated CRC.Therefore, in recent years, several studies have been conducted to dissect the mechanisms by which mesalazine interferes with CRC cell growth and survival. This review summarizes the current information on the molecular mechanisms that underlie the antineoplastic action of mesalazine.

  5. A physical mechanism of cancer heterogeneity

    Science.gov (United States)

    Chen, Cong; Wang, Jin

    2016-02-01

    We studied a core cancer gene regulatory network motif to uncover possible source of cancer heterogeneity from epigenetic sources. When the time scale of the protein regulation to the gene is faster compared to the protein synthesis and degradation (adiabatic regime), normal state, cancer state and an intermediate premalignant state emerge. Due to the epigenetics such as DNA methylation and histone remodification, the time scale of the protein regulation to the gene can be slower or comparable to the protein synthesis and degradation (non-adiabatic regime). In this case, many more states emerge as possible phenotype alternations. This gives the origin of the heterogeneity. The cancer heterogeneity is reflected from the emergence of more phenotypic states, larger protein concentration fluctuations, wider kinetic distributions and multiplicity of kinetic paths from normal to cancer state, higher energy cost per gene switching, and weaker stability.

  6. Wilson's disease: a comprehensive review of the molecular mechanisms.

    Science.gov (United States)

    Wu, Fei; Wang, Jing; Pu, Chunwen; Qiao, Liang; Jiang, Chunmeng

    2015-01-01

    Wilson's disease (WD), also known as hepatolenticular degeneration, is an autosomal recessive inherited disorder resulting from abnormal copper metabolism. Reduced copper excretion causes an excessive deposition of the copper in many organs such as the liver, central nervous system (CNS), cornea, kidney, joints, and cardiac muscle where the physiological functions of the affected organs are impaired. The underlying molecular mechanisms for WD have been extensively studied. It is now believed that a defect in P-type adenosine triphosphatase (ATP7B), the gene encoding the copper transporting P-type ATPase, is responsible for hepatic copper accumulation. Deposited copper in the liver produces toxic effects via modulating several molecular pathways. WD can be a lethal disease if left untreated. A better understanding of the molecular mechanisms causing the aberrant copper deposition and organ damage is the key to developing effective management approaches.

  7. Xenogeneic homologous genes, molecular evolution and cancer therapy

    Institute of Scientific and Technical Information of China (English)

    田聆; 魏于全

    2001-01-01

    Cancer is one of the main causes for death of human beings to date, and cancer biotherapy (mainlyimmunotherapy and gene therapy) has become the most promising approach after surgical therapy, radiotherapy andchemotherapy. However, there are still many limitations on cancer immunotherapy and gene therapy; therefore great ef-fort is being made to develop new strategies. It has been known that, in the process of evolution, a number of genes, theso-called xenogeneic homologous genes, are well-conserved and show the structural and/or functional similarity betweenvarious species to some degree. The nucleotide changes between various xenogeneic homologous genes are derived frommutation, and most of them are neutral mutations. Considering that the subtle differences in xenogeneic homologousgenes can break immune tolerance, enhance the immunogenicity and induce autologous immune response so as to elimi-nate tumor cells, we expect that a strategy of inducing autoimmune response using the property of xenogeneic homologousgenes will become a new therapy for cancer. Moreover, this therapy can also be used in the treatment of other diseases,such as autoimmune diseases and AIDS. This article will discuss the xenogeneic homologous genes, molecular evolutionand cancer therapy.

  8. Molecular targets of cancer chemoprevention by garlic-derived organosulfides

    Institute of Scientific and Technical Information of China (English)

    Anna HERMAN-ANTOSIEWICZ; Anna A POWOLNY; Shivendra V SINGH

    2007-01-01

    The medicinal benefits of Allium vegetables, especially garlic, have been noted throughout recorded history. The known health benefits of Allium vegetables and their constituents include cardiovascular protective effects, stimulation of immune function, reduction of blood glucose level, radioprotection, improvement of memory loss, protection against microbial, viral and fungal infections, as well as anticancer effects. Population-based case control studies have suggested an inverse correlation between dietary intake of Allium vegetables and the risk of different types of cancers. The anticarcinogenic effect of Allium vegetables in-eluding garlic is attributed to organosulfur compounds (OSC), which are highly effective in affording protection against cancer in animal models induced by a variety of chemical carcinogens. More recent studies have shown that certain naturally occurring OSC analogues can suppress proliferation of cancer cells in culture and in vivo. The OSC-induced changes in the proliferation of cancer Cellsare frequently associated with perturbations in cell cycle progression and induc-tion of G2/M phase arrest. The OSC have also been demonstrated to induce apoptosis via the intrinsic pathway by altering the ratio of the Bc1-2 family of proteins both in cell culture and in in vivo models. Anti-angiogenic activity for garlic-derived OSC has also been documented. This article summarizes current knowledge on molecular targets of cancer chemoprevention by OSC.

  9. The Mechanism in Gastric Cancer Chemoprevention by Allicin.

    Science.gov (United States)

    Luo, Runlan; Fang, Dengyang; Hang, Hongdong; Tang, Zeyao

    2016-01-01

    Gastric cancer remains high prevalence and fatality rates in China even though its morbidity has been decreased drastically. Allicin, which is from an assistance food-garlic (Allium Sativum L), was found to be effective in gastric cancer treatment. It is a defensive substance with a board biological properties: inhibition of bacteria, fungus, virus, controlled hypertension, diabetes, and chemoprevention of several cancers, etc. Experiments have shown that allicin can be chemopreventive to gastric cancer by inhibiting the growth of cancer cells, arresting cell cycle at G2/M phase, endoplasmic reticulum (ER) stress, and mitochondria-mediated apoptosis, which includes the caspase-dependent/-independent pathways and death receptor pathway. Those mechanisms probably involve in modulating enzymatic activity, restraining DNA formation, scavenging free radicals, and affecting cell proliferation and even tumor growth. Therefore, this review is focus on the mechanism of allicin in gastric cancer. PMID:26555611

  10. Estrogen Receptor-Targeted Contrast Agents for Molecular Magnetic Resonance Imaging of Breast Cancer Hormonal Status.

    Science.gov (United States)

    Pais, Adi; Degani, Hadassa

    2016-01-01

    The estrogen receptor (ER) α is overexpressed in most breast cancers, and its level serves as a major prognostic factor. It is important to develop quantitative molecular imaging methods that specifically detect ER in vivo and assess its function throughout the entire primary breast cancer and in metastatic breast cancer lesions. This study presents the biochemical and molecular features, as well as the magnetic resonance imaging (MRI) effects of two novel ER-targeted contrast agents (CAs), based on pyridine-tetra-acetate-Gd(III) chelate conjugated to 17β-estradiol (EPTA-Gd) or to tamoxifen (TPTA-Gd). The experiments were conducted in solution, in human breast cancer cells, and in severe combined immunodeficient mice implanted with transfected ER-positive and ER-negative MDA-MB-231 human breast cancer xenografts. Binding studies with ER in solution and in human breast cancer cells indicated affinities in the micromolar range of both CAs. Biochemical and molecular studies in breast cancer cell cultures showed that both CAs exhibit estrogen-like agonistic activity, enhancing cell proliferation, as well as upregulating cMyc oncogene and downregulating ER expression levels. The MRI longitudinal relaxivity was significantly augmented by EPTA-Gd in ER-positive cells as compared to ER-negative cells. Dynamic contrast-enhanced studies with EPTA-Gd in vivo indicated specific augmentation of the MRI water signal in the ER-positive versus ER-negative xenografts, confirming EPTA-Gd-specific interaction with ER. In contrast, TPTA-Gd did not show increased enhancement in ER-positive tumors and did not appear to interact in vivo with the tumors' ER. However, TPTA-Gd was found to interact strongly with muscle tissue, enhancing muscle signal intensity in a mechanism independent of the presence of ER. The specificity of EPTA-Gd interaction with ER in vivo was further verified by acute and chronic competition with tamoxifen. The chronic tamoxifen treatment also revealed that this

  11. Estrogen receptor targeted contrast agents for molecular magnetic resonance imaging of breast cancer hormonal status

    Directory of Open Access Journals (Sweden)

    Adi ePais

    2016-04-01

    Full Text Available The estrogen receptor α (ER is over expressed in most breast cancers and its level serves as a major prognostic factor. It is important to develop quantitative molecular imaging methods that specifically detect ER in vivo and assess its function throughout the entire primary breast cancer, as well as in metastatic breast cancer lesions. This study presents the biochemical and molecular features, as well as the magnetic resonance imaging effects of two novel ER- targeted contrast agents (CAs based on pyridine-tetra-acetate-Gd(III chelate conjugated to 17β-estradiol (EPTA-Gd or to tamoxifen (TPTA-Gd. The experiments were conducted in solution, in human breast cancer cells and in severe combined immunodeficient mice implanted with transfected ER-positive and ER-negative MDA-MB-231 human breast cancer xenografts. Binding studies with ER in solution and in human breast cancer cells indicated affinities in the micromolar range of both CAs. Biochemical and molecular studies in breast cancer cell cultures showed that both CAs exhibit estrogen like agonistic activity, enhancing cell proliferation, as well as up-regulating cMyc oncogene and down-regulating ER expression levels. The MRI longitudinal relaxivity was significantly augmented by EPTA-Gd in ER-positive cells as compared to ER-negative cells. Dynamic contrast enhanced studies with EPTA-Gd in vivo indicated specific augmentation of the MRI water signal in the ER-positive versus ER-negative xenografts, confirming EPTA-Gd specific interaction with ER. In contrast, TPTA-Gd did not show increased enhancement in ER-positive tumors and did not appear to interact in vivo with the tumors’ ER. However, TPTA-Gd was found to interact strongly with muscle tissue, enhancing muscle signal intensity in a mechanism independent of the presence of ER. The specificity of EPTA-Gd interaction with ER in vivo was further verified by acute and chronic competition with tamoxifen. The chronic tamoxifen treatment also

  12. Identifying molecular targets of lifestyle modifications in colon cancer prevention

    Directory of Open Access Journals (Sweden)

    Molly Marie Derry

    2013-05-01

    Full Text Available One in four deaths in the United States is cancer-related, and colorectal cancer (CRC is the second leading cause of cancer-associated deaths. Screening strategies are utilized but have not reduced disease incidence or mortality. In this regard, there is an interest in cancer preventive strategies focusing on lifestyle intervention, where specific etiologic factors involved in cancer initiation, promotion, and progression could be targeted. For example, exposure to dietary carcinogens, such as nitrosamines and polycyclic aromatic hydrocarbons influences colon carcinogenesis. Furthermore, dietary deficiencies could alter sensitivity to genetic damage and influence carcinogen metabolism contributing to CRC. High alcohol consumption increases the risk of mutations including the fact that acetaldehyde, an ethanol metabolite, is classified as a group 1 carcinogen. Tobacco smoke exposure is also a risk factor for cancer development; ~20% of CRCs are associated with smoking. Additionally, obese patients have a higher risk of cancer development, which is further supported by the fact that physical activity decreases CRC risk by 55%. Similarly, chronic inflammatory conditions also increase the risk of CRC development. Moreover, the circadian clock alters digestion and regulates other biochemical, physiological and behavioral processes that could positively influence CRC. Taken together, colon carcinogenesis involves a number of etiological factors, and therefore, to create effective preventive strategies, molecular targets need to be identified and beleaguered prior to disease progression. With this in mind, the following is a comprehensive review identifying downstream target proteins of the above lifestyle risk factors, which are modulated during colon carcinogenesis and could be targeted for CRC prevention by novel agents including phytochemicals.

  13. Ligand binding to anti-cancer target CD44 investigated by molecular simulations.

    Science.gov (United States)

    Nguyen, Tin Trung; Tran, Duy Phuoc; Pham Dinh Quoc Huy; Hoang, Zung; Carloni, Paolo; Van Pham, Phuc; Nguyen, Chuong; Li, Mai Suan

    2016-07-01

    CD44 is a cell-surface glycoprotein and receptor for hyaluronan, one of the major components of the tumor extracellular matrix. There is evidence that the interaction between CD44 and hyaluronan promotes breast cancer metastasis. Recently, the molecule F-19848A was shown to inhibit hyaluronan binding to receptor CD44 in a cell-based assay. In this study, we investigated the mechanism and energetics of F-19848A binding to CD44 using molecular simulation. Using the molecular mechanics/Poisson Boltzmann surface area (MM-PBSA) method, we obtained the binding free energy and inhibition constant of the complex. The van der Waals (vdW) interaction and the extended portion of F-19848A play key roles in the binding affinity. We screened natural products from a traditional Chinese medicine database to search for CD44 inhibitors. From combining pharmaceutical requirements with docking and molecular dynamics simulations, we found ten compounds that are potentially better or equal to the F-19848A ligand at binding to CD44 receptor. Therefore, we have identified new candidates of CD44 inhibitors, based on molecular simulation, which may be effective small molecules for the therapy of breast cancer. PMID:27342250

  14. A Physical Mechanism and Global Quantification of Breast Cancer

    Science.gov (United States)

    Yu, Chong; Wang, Jin

    2016-01-01

    Initiation and progression of cancer depend on many factors. Those on the genetic level are often considered crucial. To gain insight into the physical mechanisms of breast cancer, we construct a gene regulatory network (GRN) which reflects both genetic and environmental aspects of breast cancer. The construction of the GRN is based on available experimental data. Three basins of attraction, representing the normal, premalignant and cancer states respectively, were found on the phenotypic landscape. The progression of breast cancer can be seen as switching transitions between different state basins. We quantified the stabilities and kinetic paths of the three state basins to uncover the biological process of breast cancer formation. The gene expression levels at each state were obtained, which can be tested directly in experiments. Furthermore, by performing global sensitivity analysis on the landscape topography, six key genes (HER2, MDM2, TP53, BRCA1, ATM, CDK2) and four regulations (HER2⊣TP53, CDK2⊣BRCA1, ATM→MDM2, TP53→ATM) were identified as being critical for breast cancer. Interestingly, HER2 and MDM2 are the most popular targets for treating breast cancer. BRCA1 and TP53 are the most important oncogene of breast cancer and tumor suppressor gene, respectively. This further validates the feasibility of our model and the reliability of our prediction results. The regulation ATM→MDM2 has been extensive studied on DNA damage but not on breast cancer. We notice the importance of ATM→MDM2 on breast cancer. Previous studies of breast cancer have often focused on individual genes and the anti-cancer drugs are mainly used to target the individual genes. Our results show that the network-based strategy is more effective on treating breast cancer. The landscape approach serves as a new strategy for analyzing breast cancer on both the genetic and epigenetic levels and can help on designing network based medicine for breast cancer. PMID:27410227

  15. Investigation of deformation mechanisms of staggered nanocomposites using molecular dynamics

    Science.gov (United States)

    Mathiazhagan, S.; Anup, S.

    2016-08-01

    Biological materials with nanostructure of regularly or stair-wise staggered arrangements of hard platelets reinforced in a soft protein matrix have superior mechanical properties. Applications of these nanostructures to ceramic matrix composites could enhance their toughness. Using molecular dynamics simulations, mechanical behaviour of the bio-inspired nanocomposites is studied. Regularly staggered model shows better flow behaviour compared to stair-wise staggered model due to the symmetrical crack propagation along the interface. Though higher stiffness and strength are obtained for stair-wise staggered models, rapid crack propagation reduces the toughness. Arresting this crack propagation could lead to superior mechanical properties in stair-wise staggered models.

  16. A Modiifed Molecular Structure Mechanics Method for Analysis of Graphene

    Institute of Scientific and Technical Information of China (English)

    HUA Jun; LI Dongbo; ZHAO Dong; LIANG Shengwei; LIU Qinlong; JIA Ruiyan

    2015-01-01

    Based on molecular mechanics and the deformation characteristics of the atomic lattice structure of graphene, a modiifed molecular structure mechanics method was developed to improve the original one, that is, the semi-rigid connections were used to model the bond angle variations between the C-C bonds in graphene. The simulated results show that the equivalent space frame model with semi-rigid connections for graphene proposed in this article is a simple, efifcient, and accurate model to evaluate the equivalent elastic properties of graphene. Though the present computational model of the semi-rigid connected space frame is only applied to characterize the mechanical behaviors of the space lattices of graphene, it has more potential applications in the static and dynamic analyses of graphene and other nanomaterials.

  17. Normal Mode Analysis with Molecular Geometry Restraints: Bridging Molecular Mechanics and Elastic Models

    OpenAIRE

    Lu, Mingyang; Ma, Jianpeng

    2011-01-01

    A new method for normal mode analysis is reported for all-atom structures using molecular geometry restraints (MGR). Similar to common molecular mechanics force fields, the MGR potential contains short- and long-range terms. The short-range terms are defined by molecular geometry, i.e. bond lengths, angles and dihedrals; the long-range term is similar to that in elastic network models. Each interaction term uses a single force constant parameter, and is determined by fitting against a set of ...

  18. Heat shock proteins in hepatocellular carcinoma: Molecular mechanism and therapeutic potential.

    Science.gov (United States)

    Wang, Cun; Zhang, Yurong; Guo, Kun; Wang, Ning; Jin, Haojie; Liu, Yinkun; Qin, Wenxin

    2016-04-15

    Heat shock proteins (HSPs) are highly conserved proteins, which are expressed at low levels under normal conditions, but significantly induced in response to cellular stresses. As molecular chaperones, HSPs play crucial roles in protein homeostasis, apoptosis, invasion and cellular signaling transduction. The induction of HSPs is an important part of heat shock response, which could help cancer cells to adapt to stress conditions. Because of the constant stress condition in tumor microenvironment, HSPs overexpression is widely reported in many human cancers. In light of the significance of HSPs for cancer cells to survive and obtain invasive phenotype under stress condition, HSPs are often associated with poor prognosis and treatment resistance in many types of human cancers. It has been described that upregulation of HSPs may serve as diagnostic and prognostic markers in hepatocellular carcinoma (HCC). Targeting HSPs with specific inhibitor alone or in combination with chemotherapy regimens holds promise for the improvement of outcomes for HCC patients. In this review, we summarize the expression profiles, functions and molecular mechanisms of HSPs (HSP27, HSP70 and HSP90) as well as a HSP-like protein (clusterin) in HCC. In addition, we address progression and challenges in targeting these HSPs as novel therapeutic strategies in HCC. PMID:26853533

  19. Biologia molecular do câncer cervical Molecular biology of cervical cancer

    Directory of Open Access Journals (Sweden)

    Waldemar Augusto Rivoire

    2006-01-01

    Full Text Available A carcinogênese é um processo de múltiplas etapas. Alterações no equilíbrio citogenético ocorrem na transformação do epitélio normal a câncer cervical. Numerosos estudos apoiam a hipótese de que a infecção por HPV está associada com o desenvolvimento de alterações malignas e pré-malignas do trato genital inferior. Neste trabalho são apresentadas as bases para a compreensão da oncogênese cervical. O ciclo celular é controlado por proto-oncogenes e genes supressores. Quando ocorrem mutações, proto-oncogenes tornam-se oncogenes, que são carcinogênicos e causam multiplicação celular excessiva. A perda da ação de genes supressores funcionais pode levar a célula ao crescimento inadequado. O ciclo celular também pode ser alterado pela ação de vírus, entre eles o HPV (Human Papiloma Virus, de especial interesse na oncogênese cervical. Os tipos de HPV 16 e 18 são os de maior interesse, freqüentemente associados a câncer cervical e anal. O conhecimento das bases moleculares que estão envolvidas na oncogênese cervical tem sido possível devido a utilização de técnicas avançadas de biologia molecular. A associação destas técnicas aos métodos diagnósticos clássicos, poderão levar a uma melhor avaliação das neoplasias cervicais e auxiliar no desenvolvimento de novas terapias, talvez menos invasivas e mais efetivas.Carcinogenesis involves several steps. Disorders of the cytogenetic balance occur during the evolution from normal epithelium to cervical cancer. Several studies support the hypothesis that the Human Papiloma Virus (HPV infection is associated to development of premalignant and malignant lesions of cervical cancer. In this review we show the basis to understand cervical oncogenesis. The cell cycle is controlled by protooncogenes and supressive genes. This orchestrated cell cycle can be affected by virus such as HPV. Of special interest in the cervical carcinogenesis are the HPV subtypes 16 and 18

  20. Protective mechanism against cancer found in progeria patient cells

    Science.gov (United States)

    NCI scientists have studied cells of patients with an extremely rare genetic disease that is characterized by drastic premature aging and discovered a new protective cellular mechanism against cancer. They found that cells from patients with Hutchinson Gi

  1. Women at high risk of breast cancer: Molecular characteristics, clinical presentation and management.

    Science.gov (United States)

    Kleibl, Zdenek; Kristensen, Vessela N

    2016-08-01

    The presence of breast cancer in any first-degree female relative in general nearly doubles the risk for a proband and the risk gradually increases with the number of affected relatives. Current advances in molecular oncology and oncogenetics may enable the identification of high-risk individuals with breast-cancer predisposition. The best-known forms of hereditary breast cancer (HBC) are caused by mutations in the high-penetrance genes BRCA1 and BRCA2. Other genes, including PTEN, TP53, STK11/LKB1, CDH1, PALB2, CHEK2, ATM, MRE11, RAD50, NBS1, BRIP1, FANCA, FANCC, FANCM, RAD51, RAD51B, RAD51C, RAD51D, and XRCC2 have been described as high- or moderate-penetrance breast cancer-susceptibility genes. The majority of breast cancer-susceptibility genes code for tumor suppressor proteins that are involved in critical processes of DNA repair pathways. This is of particular importance for those women who, due to their increased risk of breast cancer, may be subjected to more frequent screening but due to their repair deficiency might be at the risk of developing radiation-induced malignancies. It has been proven that cancers arising from the most frequent BRCA1 gene mutation carriers differ significantly from the sporadic disease of age-matched controls in their histopathological appearances and molecular characteristics. The increased depth of mutation detection brought by next-generation sequencing and a better understanding of the mechanisms through which these mutations cause the disease will bring novel insights in terms of oncological prevention, diagnostics, and therapeutic options for HBC patients. PMID:27318168

  2. Women at high risk of breast cancer: Molecular characteristics, clinical presentation and management.

    Science.gov (United States)

    Kleibl, Zdenek; Kristensen, Vessela N

    2016-08-01

    The presence of breast cancer in any first-degree female relative in general nearly doubles the risk for a proband and the risk gradually increases with the number of affected relatives. Current advances in molecular oncology and oncogenetics may enable the identification of high-risk individuals with breast-cancer predisposition. The best-known forms of hereditary breast cancer (HBC) are caused by mutations in the high-penetrance genes BRCA1 and BRCA2. Other genes, including PTEN, TP53, STK11/LKB1, CDH1, PALB2, CHEK2, ATM, MRE11, RAD50, NBS1, BRIP1, FANCA, FANCC, FANCM, RAD51, RAD51B, RAD51C, RAD51D, and XRCC2 have been described as high- or moderate-penetrance breast cancer-susceptibility genes. The majority of breast cancer-susceptibility genes code for tumor suppressor proteins that are involved in critical processes of DNA repair pathways. This is of particular importance for those women who, due to their increased risk of breast cancer, may be subjected to more frequent screening but due to their repair deficiency might be at the risk of developing radiation-induced malignancies. It has been proven that cancers arising from the most frequent BRCA1 gene mutation carriers differ significantly from the sporadic disease of age-matched controls in their histopathological appearances and molecular characteristics. The increased depth of mutation detection brought by next-generation sequencing and a better understanding of the mechanisms through which these mutations cause the disease will bring novel insights in terms of oncological prevention, diagnostics, and therapeutic options for HBC patients.

  3. Molecular Modification of Metadherin/MTDH Impacts the Sensitivity of Breast Cancer to Doxorubicin.

    Directory of Open Access Journals (Sweden)

    Zhenchuan Song

    Full Text Available Breast cancer is a leading cause of death in women and with an increasing worldwide incidence. Doxorubicin, as a first-line anthracycline-based drug is conventional used on breast cancer clinical chemotherapy. However, the drug resistances limited the curative effect of the doxorubicin therapy in breast cancer patients, but the molecular mechanism determinants of breast cancer resistance to doxorubicin chemotherapy are not fully understood. In order to explore the association between metadherin (MTDH and doxorubicin sensitivity, the differential expressions of MTDH in breast cancer cell lines and the sensitivity to doxorubicin of breast cancer cell lines were investigated.The mRNA and protein expression of MTDH were determined by real-time PCR and Western blot in breast cancer cells such as MDA-MB-231, MCF-7, MDA-MB-435S, MCF-7/ADR cells. Once MTDH gene was knocked down by siRNA in MCF-7/ADR cells and overexpressed by MTDH plasmid transfection in MDA-MB-231 cells, the cell growth and therapeutic sensitivity of doxorubicin were evaluated using MTT and the Cell cycle assay and apoptosis rate was determined by flow cytometry.MCF-7/ADR cells revealed highly expressed MTDH and MDA-MB-231 cells had the lowest expression of MTDH. After MTDH gene was knocked down, the cell proliferation was inhibited, and the inhibitory rate of cell growth and apoptosis rate were enhanced, and the cell cycle arrest during the G0/G1 phase in the presence of doxorubicin treatment. On the other hand, the opposite results were observed in MDA-MB-231 cells with overexpressed MTDH gene.MTDH gene plays a promoting role in the proliferation of breast cancer cells and its high expression may be associated with doxorubicin sensitivity of breast cancer.

  4. Molecular mechanisms of thyroid tumorigenesis; Molekulare Mechanismen der Schilddruesentumorgenese

    Energy Technology Data Exchange (ETDEWEB)

    Krause, K.; Fuehrer, D. [Universitaetsklinikum Leipzig (Germany). Abt. fuer Endokrinolgoie, Diabetologie und Nephrologie

    2008-09-15

    Thyroid nodules are the most frequent endocrine disorder and occur in approximately 30% of the German population. Thyroid nodular disease constitutes a very heterogeneous entity. A striking diversity of possible functional and morphological features of a thyroid tumour derived from the same thyroid ancestor cell, is a hallmark of thyroid tumorigenesis and is due to specific genetic alterations. Defects in known candidate genes can be found in up to 70% of differentiated thyroid carcinomas and determine the respective cancer phenotype. Papillary thyroid cancers (PTC) harbour BRAF (or much less frequently RAS) mutations in sporadically occurring tumours, while radiation-induced PTC display chromosomal rearrangements such as RET, TRK, APR9 / BRAF. These genetic events results in constitutive MAPKinase activation. Follicular thyroid cancers (FTC) harbour RAS mutations or PAX8/ PPAR{gamma} rearrangements, both of which, however have also been identified in follicular adenoma. In addition, recent studies show, that activation of PI3K/AKT signalling occurs with high frequency in follicular thyroid tumours. Undifferentiated (anaplastic) thyroid cancers (ATC) display genetic features of FTC or PTC, in addition to aberant activation of multiple tyrosinkinase pathways (overexpression or mutations in PI3K and MAPK pathways). This underscores the concept of a sequential evolution of ATC from differentiated thyroid cancer, a process widely conceived to be triggered by p53 inactivation. In contrast, the molecular pathogenesis of benign thyroid tumours, in particular cold thyroid nodules is less known, except for toxic thyroid nodules, which arise from constitutive activation of cAMP signalling, predominantly through TSHR mutations. (orig.)

  5. Molecular dynamics simulations of diffusion mechanisms in NiAl

    Energy Technology Data Exchange (ETDEWEB)

    Soule De Bas, B.; Farkas, D

    2003-03-14

    Molecular dynamics simulations of the diffusion process in ordered B2 NiAl at high temperature were performed using an embedded atom interatomic potential. Diffusion occurs through a variety of cyclic mechanisms that accomplish the motion of the vacancy through nearest neighbor jumps restoring order to the alloy at the end of the cycle. The traditionally postulated six-jump cycle is only one of the various cycles observed and some of these are quite complex. A detailed sequential analysis of the observed six-jump cycles was performed and the results are analyzed in terms of the activation energies for individual jumps calculated using molecular statics simulations.

  6. Genetic classification and molecular mechanisms of primary dystonia

    Institute of Scientific and Technical Information of China (English)

    Xueping Chen; Huifang Shang; Zuming Luo

    2008-01-01

    BACKGROUND: Primary dystonia is a heterogeneous disease, with a complex genetic basis. In previous studies, primary dystonia was classified according to age of onset, involved regions, and other clinical characteristics. With the development of molecular genetics, new virulence genes and sites have been discovered. Therefore, there is a gradual understanding of the various forms of dystonia, based on new viewpoints. There are 15 subtypes of dystonia, based on the molecular level, i.e., DYT1 to DYT15. OBJECTIVE: To analyze the genetic development of dystonia in detail, and to further investigate molecular mechanisms of dystonia. RETRIEVAL STRATEGY: A computer-based online search was conducted in PubMed for English language publications containing the keywords "dystonia and genetic" from January 1980 to March 2007. There were 105 articles in total. Inclusion criteria: ① the contents of the articles should closely address genetic classification and molecular mechanisms of primary dystonia; ② the articles published in recent years or in high-impact journals took preference. Exclusion criteria: duplicated articles. LITERATURE EVALUATION: The selected articles were on genetic classification and molecular genetics mechanism of primary dystonia. Of those, 27 were basic or clinical studies. DATA SYNTHESIS: ① Dystonia is a heterogeneous disease, with a complex genetic basis. According to the classification of the Human Genome Organization, there are 15 dystonia subtypes, based on genetics, i.e., DYT1-DYT15,including primary dystonia, dystonia plus syndrome, degeneration plus dystonia, and paroxysmal dyskinesia plus dystonia. ② To date, the chromosomes of 13 subtypes have been localized; however, DYT2 and DYT4 remain unclear. Six subtypes have been located within virulence genes. Specifically, torsinA gene expression results in the DYT1 genotype; autosomal dominant GTP cyclohydrolase I gene expression and recessive tyrosine hydroxylase expression result in the DYT5

  7. Mechanisms of immune response regulation in lung cancer

    OpenAIRE

    Domagala-Kulawik, Joanna; Osinska, Iwona; Hoser, Grazyna

    2014-01-01

    Lung cancer is a leading cause of cancer deaths. As a solid tumor with low antigenicity and heterogenic phenotype lung cancer evades host immune defense. The cytotoxic anticancer effect is suppressed by a complex mechanism in tumor microenvironment. The population of regulatory T cells (Tregs) plays a crucial role in this inhibition of immune response. Tregs are defined by presence of forkhead box P3 (Foxp3) molecule. The high expression of Foxp3 was found in lung cancer cells and in tumor in...

  8. MicroRNAs and cancer resistance: A new molecular plot.

    Science.gov (United States)

    Fanini, F; Fabbri, M

    2016-05-01

    The most common cause of cancer relapse is drug resistance, acquired or intrinsic, which strongly limits the efficacy of both conventional and new targeted chemotherapy. MicroRNAs (miRNAs) are a growing, large family of short noncoding RNAs frequently dysregulated in malignancies. Although the mechanism of miRNA-mediated drug resistance is not fully understood, an increasing amount of evidence suggests their involvement in the acquisition of tumor cell drug resistance, pointing towards the need for novel and more innovative therapeutic approaches. Use of antagomiRs or mimics can modulate specific miRNAs in order to restore gene networks and signaling pathways, perhaps optimizing chemotherapies by increasing cancer cell sensitivity to drugs. The aim of this review is to provide a state-of-the-art scenario with regard to the most recent discoveries in the field of miRNAs involved in the process of resistance to cancer therapy.

  9. Molecular Endoscopic Ultrasound for Diagnosis of Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bournet, Barbara [Department of Gastroenterology, University Hospital Center Rangueil, 1 avenue Jean Poulhès, TSA 50032, 31059 Toulouse Cedex 9 (France); INSERM U1037, University Hospital Center Rangueil, Toulouse (France); Pointreau, Adeline; Delpu, Yannick; Selves, Janick; Torrisani, Jerome [INSERM U1037, University Hospital Center Rangueil, Toulouse (France); Buscail, Louis, E-mail: buscail.l@chu-toulouse.fr [Department of Gastroenterology, University Hospital Center Rangueil, 1 avenue Jean Poulhès, TSA 50032, 31059 Toulouse Cedex 9 (France); INSERM U1037, University Hospital Center Rangueil, Toulouse (France); Cordelier, Pierre [INSERM U1037, University Hospital Center Rangueil, Toulouse (France)

    2011-02-24

    Endoscopic ultrasound-guided fine needle aspiration-biopsy is a safe and effective technique in diagnosing and staging of pancreatic ductal adenocarcinoma. However its predictive negative value does not exceed 50% to 60%. Unfortunately, the majority of pancreatic cancer patients have a metastatic and/or a locally advanced disease (i.e., not eligible for curative resection) which explains the limited access to pancreatic tissue specimens. Endoscopic ultrasound-guided fine needle aspiration-biopsy is the most widely used approach for cytological and histological material sampling in these situations used in up to two thirds of patients with pancreatic cancer. Based on this unique material, we and others developed strategies to improve the differential diagnosis between carcinoma and inflammatory pancreatic lesions by analysis of KRAS oncogene mutation, microRNA expression and methylation, as well as mRNA expression using both qRT-PCR and Low Density Array Taqman analysis. Indeed, differentiating pancreatic cancer from pseudotumoral chronic pancreatitis remains very difficult in current clinical practice, and endoscopic ultrasound-guided fine needle aspiration-biopsy analysis proved to be very helpful. In this review, we will compile the clinical and molecular advantages of using endoscopic ultrasound-guided fine needle aspiration-biopsy in managing pancreatic cancer.

  10. Molecular Endoscopic Ultrasound for Diagnosis of Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Pierre Cordelier

    2011-02-01

    Full Text Available Endoscopic ultrasound-guided fine needle aspiration-biopsy is a safe and effective technique in diagnosing and staging of pancreatic ductal adenocarcinoma. However its predictive negative value does not exceed 50% to 60%. Unfortunately, the majority of pancreatic cancer patients have a metastatic and/or a locally advanced disease (i.e., not eligible for curative resection which explains the limited access to pancreatic tissue specimens. Endoscopic ultrasound-guided fine needle aspiration-biopsy is the most widely used approach for cytological and histological material sampling in these situations used in up to two thirds of patients with pancreatic cancer. Based on this unique material, we and others developed strategies to improve the differential diagnosis between carcinoma and inflammatory pancreatic lesions by analysis of KRAS oncogene mutation, microRNA expression and methylation, as well as mRNA expression using both qRT-PCR and Low Density Array Taqman analysis. Indeed, differentiating pancreatic cancer from pseudotumoral chronic pancreatitis remains very difficult in current clinical practice, and endoscopic ultrasound-guided fine needle aspiration-biopsy analysis proved to be very helpful. In this review, we will compile the clinical and molecular advantages of using endoscopic ultrasound-guided fine needle aspiration-biopsy in managing pancreatic cancer.

  11. Molecular Endoscopic Ultrasound for Diagnosis of Pancreatic Cancer

    International Nuclear Information System (INIS)

    Endoscopic ultrasound-guided fine needle aspiration-biopsy is a safe and effective technique in diagnosing and staging of pancreatic ductal adenocarcinoma. However its predictive negative value does not exceed 50% to 60%. Unfortunately, the majority of pancreatic cancer patients have a metastatic and/or a locally advanced disease (i.e., not eligible for curative resection) which explains the limited access to pancreatic tissue specimens. Endoscopic ultrasound-guided fine needle aspiration-biopsy is the most widely used approach for cytological and histological material sampling in these situations used in up to two thirds of patients with pancreatic cancer. Based on this unique material, we and others developed strategies to improve the differential diagnosis between carcinoma and inflammatory pancreatic lesions by analysis of KRAS oncogene mutation, microRNA expression and methylation, as well as mRNA expression using both qRT-PCR and Low Density Array Taqman analysis. Indeed, differentiating pancreatic cancer from pseudotumoral chronic pancreatitis remains very difficult in current clinical practice, and endoscopic ultrasound-guided fine needle aspiration-biopsy analysis proved to be very helpful. In this review, we will compile the clinical and molecular advantages of using endoscopic ultrasound-guided fine needle aspiration-biopsy in managing pancreatic cancer

  12. Pancreatic Cancer Gene Therapy: From Molecular Targets to Delivery Systems

    Energy Technology Data Exchange (ETDEWEB)

    Fillat, Cristina, E-mail: cristina.fillat@crg.es; Jose, Anabel; Ros, Xavier Bofill-De; Mato-Berciano, Ana; Maliandi, Maria Victoria; Sobrevals, Luciano [Programa Gens i Malaltia, Centre de Regulació Genòmica-CRG, UPF, Parc de Recerca Biomedica de Barcelona-PRBB and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona (Spain)

    2011-01-18

    The continuous identification of molecular changes deregulating critical pathways in pancreatic tumor cells provides us with a large number of novel candidates to engineer gene-targeted approaches for pancreatic cancer treatment. Targets—both protein coding and non-coding—are being exploited in gene therapy to influence the deregulated pathways to facilitate cytotoxicity, enhance the immune response or sensitize to current treatments. Delivery vehicles based on viral or non-viral systems as well as cellular vectors with tumor homing characteristics are a critical part of the design of gene therapy strategies. The different behavior of tumoral versus non-tumoral cells inspires vector engineering with the generation of tumor selective products that can prevent potential toxic-associated effects. In the current review, a detailed analysis of the different targets, the delivery vectors, the preclinical approaches and a descriptive update on the conducted clinical trials are presented. Moreover, future possibilities in pancreatic cancer treatment by gene therapy strategies are discussed.

  13. Pancreatic Cancer Gene Therapy: From Molecular Targets to Delivery Systems

    International Nuclear Information System (INIS)

    The continuous identification of molecular changes deregulating critical pathways in pancreatic tumor cells provides us with a large number of novel candidates to engineer gene-targeted approaches for pancreatic cancer treatment. Targets—both protein coding and non-coding—are being exploited in gene therapy to influence the deregulated pathways to facilitate cytotoxicity, enhance the immune response or sensitize to current treatments. Delivery vehicles based on viral or non-viral systems as well as cellular vectors with tumor homing characteristics are a critical part of the design of gene therapy strategies. The different behavior of tumoral versus non-tumoral cells inspires vector engineering with the generation of tumor selective products that can prevent potential toxic-associated effects. In the current review, a detailed analysis of the different targets, the delivery vectors, the preclinical approaches and a descriptive update on the conducted clinical trials are presented. Moreover, future possibilities in pancreatic cancer treatment by gene therapy strategies are discussed

  14. Genomics Study of Gastric Cancer and Its Molecular Subtypes.

    Science.gov (United States)

    Yuen, Siu Tsan; Leung, Suet Yi

    2016-01-01

    Gastric cancer is a heterogeneous disease encompassing diverse morphological (intestinal versus diffuse) and molecular subtypes (MSI, EBV, TP53 mutation). Recent advances in genomic technology have led to an improved understanding of the driver gene mutational profile, gene expression, and epigenetic alterations that underlie each of the subgroups, with therapeutic implications in some of these alterations. There have been attempts to classify gastric cancers based on these genomic features, with an aim to improve prognostication and predict responsiveness to specific drug therapy. The eventual aims of these genomic studies are to develop deep biological insights into the carcinogenic pathway in each of these subtypes. Future large-scale drug screening strategies may then be able to link these genomic features to drug responsiveness, eventually leading to genome-guided personalized medicine with improved cure rates. PMID:27573784

  15. Molecular Characterization of ERα-positive and Triple Negative Breast Cancer

    NARCIS (Netherlands)

    Severson, T.M.

    2016-01-01

    Breast cancer, one of the most common of all cancers, is diagnosed in over 1.5 million people world-wide each year. Overall, treatments for breast cancer are considered relatively successful, however recurrence is a clinical problem of paramount importance. Molecular subtypes of breast cancer, defin

  16. Lobular breast cancer: Clinical, molecular and morphological characteristics.

    Science.gov (United States)

    Christgen, Matthias; Steinemann, Doris; Kühnle, Elna; Länger, Florian; Gluz, Oleg; Harbeck, Nadia; Kreipe, Hans

    2016-07-01

    Infiltrating lobular breast cancer (ILBC) is the most common special breast cancer subtype. This review provides a comprehensive description of ILBC characteristics, including epidemiology, clinical features, molecular genetics and histomorphology. Twenty detailed supplemental data tables guide through primary data of more than 200 original studies. Meta-analyses indicate that ILBC is at least twice as common in the Western world as it is in other geographic regions. ILBC is over-represented in so-called interval carcinomas and in primary metastatic breast cancer. ILBC is also associated higher age, higher pT stage and hormone receptor (ER/PR) positivity. Pathological complete response rates after neoadjuvant chemotherapy are low, ranging between 0% and 11%. Positive resection margins after breast-conserving surgery are comparatively frequent and 17% to 65% of patients undergo a second surgical intervention. Depending on the morphological stringency in the diagnosis of ILBC, lack of E-cadherin expression is observed in 55% to 100% of cases. CDH1/E-cadherin mutation detection rates vary between 12% and 83%. Various additional molecular factors, including PIK3CA, TP53, FOXA1, FGFR1, ZNF703 and BCAR4, have been implicated in ILBC or progression of lobular carcinoma in situ (LCIS) to invasive cancer and are discussed in detail. Eight instructive figure plates recapitulate the histomorphology of ILBC and its variants. Furthermore, we draw attention to rarely addressed histological details, such as two-sided nuclear compression and fat-avoiding growth at the invasion front. Last but not least, we discuss future translational research directions and emphasize the concept of synthetic lethality, which promises new options for targeted ILBC therapy.

  17. Molecular Subtyping of Serous Ovarian Tumors Reveals Multiple Connections to Intrinsic Breast Cancer Subtypes

    DEFF Research Database (Denmark)

    Jönsson, Jenny-Maria; Johansson, Ida; Dominguez-Valentin, Mev;

    2014-01-01

    with the well-established intrinsic molecular subtypes of breast cancer. METHODS: Global gene expression profiling using Illumina's HT12 Bead Arrays was applied to 59 fresh-frozen serous ovarian malignant, benign and borderline tumors. Nearest centroid classification was performed applying previously published...... to the luminal A breast cancer subtype. These findings remained when analyzed in an independent dataset, supporting links between the molecular subtypes of ovarian cancer and breast cancer beyond those recently acknowledged. CONCLUSIONS: These data link the transcriptional profiles of serous ovarian cancer...... to the intrinsic molecular subtypes of breast cancer, in line with the shared clinical and molecular features between high-grade serous ovarian cancer and basal-like breast cancer, and suggest that biomarkers and targeted therapies may overlap between these tumor subsets. The link between benign and borderline...

  18. Molecular Insights into Division of Single Human Cancer Cells in On-Chip Transparent Microtubes

    Science.gov (United States)

    2016-01-01

    In vivo, mammalian cells proliferate within 3D environments consisting of numerous microcavities and channels, which contain a variety of chemical and physical cues. External environments often differ between normal and pathological states, such as the unique spatial constraints that metastasizing cancer cells experience as they circulate the vasculature through arterioles and narrow capillaries, where they can divide and acquire elongated cylindrical shapes. While metastatic tumors cause most cancer deaths, factors impacting early cancer cell proliferation inside the vasculature and those that can promote the formation of secondary tumors remain largely unknown. Prior studies investigating confined mitosis have mainly used 2D cell culture systems. Here, we mimic aspects of metastasizing tumor cells dividing inside blood capillaries by investigating single-cell divisions of living human cancer cells, trapped inside 3D rolled-up, transparent nanomembranes. We assess the molecular effects of tubular confinement on key mitotic features, using optical high- and super-resolution microscopy. Our experiments show that tubular confinement affects the morphology and dynamics of the mitotic spindle, chromosome arrangements, and the organization of the cell cortex. Moreover, we reveal that membrane blebbing and/or associated processes act as a potential genome-safety mechanism, limiting the extent of genomic instability caused by mitosis in confined circumstances, especially in tubular 3D microenvironments. Collectively, our study demonstrates the potential of rolled-up nanomembranes for gaining molecular insights into key cellular events occurring in tubular 3D microenvironments in vivo. PMID:27267364

  19. Molecular Mechanisms of Casticin in Intervention of Cancer Cell Metastasis in Esophagus Squamous Cell Carci-noma%紫花牡荆素干预食管鳞状细胞癌细胞转移的分子机制

    Institute of Scientific and Technical Information of China (English)

    冉永刚; 游颜杰; 李海军

    2015-01-01

    目的 研究紫花牡荆素对人食管鳞状细胞癌(食管鳞癌)细胞恶性转移能力的抑制效应并探讨其分子机制. 方法 人食管鳞癌细胞株EC9706与EC109细胞经紫花牡荆素处理后,以MTT比色法测定细胞增殖能力,侵袭与迁移实验检测细胞转移能力,Western blot检测转移相关蛋白表达变化. 结果 不同浓度紫花牡荆素处理可显著抑制EC9706与EC109细胞的增殖、侵袭与迁移能力,同未加药组比较差异均有统计学意义(P<0. 05);紫花牡荆素处理下调兔抗人血管内皮生长因子(vascular endothelial growth factor,VEGF)、基质金属蛋白酶2(matrix metalloprotein-ase2,MMP2)与基质金属蛋白酶9(matrix metalloproteinase9,MMP9)表达水平,上调上皮细胞钙黏蛋白(E-cadherin)、周期素依赖性激酶10(cyclin-dependent kinase 10, CDK10)与兔抗人受体O型蛋白质酪氨酸磷酸酶(protein tyrosine phos-phatase receptor type O, PTPRO)表达. 结论 紫花牡荆素对食管鳞癌细胞恶性转移能力有明显的抑制作用,下调VEGF、MMP2与MMP9表达,上调E-cadherin、CDK10与PTPRO可能是其抑制转移的分子机制.%Objective To investigate the depressive effect of Casticin on malignant metastasis of human esopha-gus squamous cell carcinoma ( ESCC ) cells and to analyze its molecular mechanisms. Methods The EC9706 and EC109 cells in ESCC cell line were treated with Casticin, and then the thiazolyl blue ( MTT) colorimetry was used to de-tect cell abilities of proliferation, invasion and migration, and related protein expressions were detected using Western blot method. Results EC9706 and EC109 cells abilities of proliferation, invasion and migration were significantly inhib-ited after different concentrations of Casticin treatment, and the differences were statistically significant compared with those without Casticin treatment (P<0. 05);after the Casticin treatment, the expressions of vascular endothelial growth factor (VEGF), matrix

  20. Delineating Molecular Mechanisms of Squamous Tissue Homeostasis and Neoplasia: Focus on p63

    Directory of Open Access Journals (Sweden)

    Kathryn E. King

    2013-01-01

    Full Text Available Mouse models have informed us that p63 is critical for normal epidermal development and homeostasis. The p53/p63/p73 family is expressed as multiple protein isoforms due to a combination of alternative promoter usage and C-terminal alternative splicing. These isoforms can mimic or interfere with one another, and their balance ultimately determines biological outcome in a context-dependent manner. While not frequently mutated, p63, and in particular the ΔNp63 subclass, is commonly overexpressed in human squamous cell cancers. In vitro keratinocytes and murine transgenic and transplantation models have been invaluable in elucidating the contribution of altered p63 levels to cancer development, and studies have identified the roles for ΔNp63 isoforms in keratinocyte survival and malignant progression, likely due in part to their transcriptional regulatory function. These findings can be extended to human cancers; for example, the novel recognition of NFκB/c-Rel as a downstream effector of p63 has identified a role for NFκB/c-Rel in human squamous cell cancers. These models will be critical in enhancing the understanding of the specific molecular mechanisms of cancer development and progression.

  1. Mechanisms of Cancer Induction by Tobacco-Specific NNK and NNN

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Jiaping [Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612 (United States); Yang, Suping; Seng, Seyha, E-mail: sseng@bidmc.harvard.edu [Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215 (United States)

    2014-05-14

    Tobacco use is a major public health problem worldwide. Tobacco-related cancers cause millions of deaths annually. Although several tobacco agents play a role in the development of tumors, the potent effects of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) are unique. Metabolically activated NNK and NNN induce deleterious mutations in oncogenes and tumor suppression genes by forming DNA adducts, which could be considered as tumor initiation. Meanwhile, the binding of NNK and NNN to the nicotinic acetylcholine receptor promotes tumor growth by enhancing and deregulating cell proliferation, survival, migration, and invasion, thereby creating a microenvironment for tumor growth. These two unique aspects of NNK and NNN synergistically induce cancers in tobacco-exposed individuals. This review will discuss various types of tobacco products and tobacco-related cancers, as well as the molecular mechanisms by which nitrosamines, such as NNK and NNN, induce cancer.

  2. Isoforms of thyroxine-binding globulin as a model for molecular epidemiology of human cancer risk

    International Nuclear Information System (INIS)

    -binding globulin (TBG) by 50-60%, but no elevation in free T4, as compared with similar control groups of from Minsk. One of the reasons for the euthyroid syndrome in teenagers from the contaminated region was shown to be the blood isoforms in TBG. These isoforms differed in the structure of the carbohydrate components and as a rule are characterized by a prolonged circulation time. Using specific affinity chromatography, with subsequent immunological assay we shown that a certain amount of serum TBG-molecules in persons from Khojniki contains a high level of TBG (about 30% higher than the control group) containing fucosyalated biantennary sugar chains with more prolonged survival time. Previous findings showed that increased levels of fucosylation are observed for some serum glycoproteins in the blood of tumour patients. We provide evidence for variations in the TBGfuc which are contained in the serum TBG pool of patients suffering from cancer with various localisation. Thus, analysis of TBGfuc may be regarded as a prognostic marker in the determination of risk groups. The molecular mechanism of increased activity of fucosyl transferases will be discussed. We propose to measure the level of TBG fucosylated to assess the human cancer risk and habitants of contaminated region of Belarus. (authors)

  3. Molecular markers in breast cancer: new tools in imaging and prognosis

    OpenAIRE

    Vermeulen, J.F.

    2012-01-01

    Breast cancer is the most frequently diagnosed cancer in women. Although breast cancer is mainly diagnosed by mammography, other imaging modalities (e.g. MRI, PET) are increasingly used. The most recent developments in the field of molecular imaging comprise the application of near-infrared fluorescent labeled (NIRF) tracers for detection of breast cancer. Thus far, only a few molecular imaging tracers have been taken to the clinic of which most are suitable for PET. My thesis describes the e...

  4. Polycystic liver diseases: advanced insights into the molecular mechanisms.

    Science.gov (United States)

    Perugorria, Maria J; Masyuk, Tatyana V; Marin, Jose J; Marzioni, Marco; Bujanda, Luis; LaRusso, Nicholas F; Banales, Jesus M

    2014-12-01

    Polycystic liver diseases are genetic disorders characterized by progressive bile duct dilatation and/or cyst development. The large volume of hepatic cysts causes different symptoms and complications such as abdominal distension, local pressure with back pain, hypertension, gastro-oesophageal reflux and dyspnea as well as bleeding, infection and rupture of the cysts. Current therapeutic strategies are based on surgical procedures and pharmacological management, which partially prevent or ameliorate the disease. However, as these treatments only show short-term and/or modest beneficial effects, liver transplantation is the only definitive therapy. Therefore, interest in understanding the molecular mechanisms involved in disease pathogenesis is increasing so that new targets for therapy can be identified. In this Review, the genetic mechanisms underlying polycystic liver diseases and the most relevant molecular pathways of hepatic cystogenesis are discussed. Moreover, the main clinical and preclinical studies are highlighted and future directions in basic as well as clinical research are indicated.

  5. [Molecular mechanisms of the plague pathogenic agent interaction with invertebrates].

    Science.gov (United States)

    Kutyrev, V V; Eroshenko, G A; Popov, N V; Vidiaeva, N A; Konnov, N P

    2009-01-01

    Microbe Russian Anti-Plague Research Institute, Saratov, Russia The literature data and experimental results of the authors on the molecular basis of plague agent interaction with invertebrates are discussed. The details of the plague agent life cycle, its genome organization, and molecular genetic mechanisms of its survival in flea vector and on the nematode cuticule are discussed. The experimental data about the ability to form biofilms at abiotic and biotic surfaces in the Yersinia pestis strains of the main and non-main subspecies are presented. Mechanisms of horizontal and vertical transmission of plague agent are considered. The suggestion about participation of the new member in the complex parasitic biocenosis (nematode, vector parasite) is put forward. PMID:20050160

  6. Molecular mechanisms of insulin resistance in chronic hepatitis C

    Institute of Scientific and Technical Information of China (English)

    Mark W Douglas; Jacob George

    2009-01-01

    It is now widely recognized that chronic hepatitis C (CHC) is associated with insulin resistance (IR) and type 2 diabetes, so can be considered a metabolic disease. IR is most strongly associated with hepatitis C virus (HCV) genotype 1, in contrast to hepatic steatosis, which is associated with genotype 3 infection. Apart from the well-described complications of diabetes, IR in CHC predicts faster progression to fibrosis and cirrhosis that may culminate in liver failure and hepatocellular carcinoma. More recently, it has been recognized that IR in CHC predicts a poor response to antiviral therapy. The molecular mechanisms for the association between IR and HCV infection are not well defined. This review will elaborate on the clinical associations between CHC and IR and summarize current knowledge regarding the molecular mechanisms that potentially mediate HCV-associated IR.

  7. Engineering molecular mechanics: an efficient static high temperature molecular simulation technique.

    Science.gov (United States)

    Subramaniyan, Arun K; Sun, C T

    2008-07-16

    Inspired by the need for an efficient molecular simulation technique, we have developed engineering molecular mechanics (EMM) as an alternative molecular simulation technique to model high temperature (T>0 K) phenomena. EMM simulations are significantly more computationally efficient than conventional techniques such as molecular dynamics simulations. The advantage of EMM is achieved by converting the dynamic atomistic system at high temperature (T>0 K) into an equivalent static system. Fundamentals of the EMM methodology are derived using thermal expansion to modify the interatomic potential. Temperature dependent interatomic potentials are developed to account for the temperature effect. The efficiency of EMM simulations is demonstrated by simulating the temperature dependence of elastic constants of copper and nickel and the thermal stress developed in a confined copper system.

  8. Multiple breast cancer cell-lines derived from a single tumor differ in their molecular characteristics and tumorigenic potential.

    Directory of Open Access Journals (Sweden)

    Goar Mosoyan

    Full Text Available BACKGROUND: Breast cancer cell lines are widely used tools to investigate breast cancer biology and to develop new therapies. Breast cancer tissue contains molecularly heterogeneous cell populations. Thus, it is important to understand which cell lines best represent the primary tumor and have similarly diverse phenotype. Here, we describe the development of five breast cancer cell lines from a single patient's breast cancer tissue. We characterize the molecular profiles, tumorigenicity and metastatic ability in vivo of all five cell lines and compare their responsiveness to 4-hydroxytamoxifen (4-OHT treatment. METHODS: Five breast cancer cell lines were derived from a single patient's primary breast cancer tissue. Expression of different antigens including HER2, estrogen receptor (ER, CK8/18, CD44 and CD24 was determined by flow cytometry, western blotting and immunohistochemistry (IHC. In addition, a Fluorescent In Situ Hybridization (FISH assay for HER2 gene amplification and p53 genotyping was performed on all cell lines. A xenograft model in nude mice was utilized to assess the tumorigenic and metastatic abilities of the breast cancer cells. RESULTS: We have isolated, cloned and established five new breast cancer cell lines with different tumorigenicity and metastatic abilities from a single primary breast cancer. Although all the cell lines expressed low levels of ER, their growth was estrogen-independent and all had high-levels of expression of mutated non-functional p53. The HER2 gene was rearranged in all cell lines. Low doses of 4-OHT induced proliferation of these breast cancer cell lines. CONCLUSIONS: All five breast cancer cell lines have different antigenic expression profiles, tumorigenicity and organ specific metastatic abilities although they derive from a single tumor. None of the studied markers correlated with tumorigenic potential. These new cell lines could serve as a model for detailed genomic and proteomic analyses to

  9. Hyperpolarized 13C MR for Molecular Imaging of Prostate Cancer

    OpenAIRE

    Wilson, David M.; Kurhanewicz, John

    2014-01-01

    Hyperpolarization using dissolution dynamic nuclear polarization has emerged as a versatile method to dramatically improve the MR signal of low-sensitivity nuclei. This technique facilitates the study of real-time metabolism in vitro and in vivo using 13C-enriched substrates and has been applied to numerous models of human disease. In particular, several mechanisms underlying prostate cancer have been interrogated using hyperpolarized 13C MR spectroscopy. This review highlights key metabolic ...

  10. Effects of Honey and Its Mechanisms of Action on the Development and Progression of Cancer

    Directory of Open Access Journals (Sweden)

    Omotayo O. Erejuwa

    2014-02-01

    Full Text Available Honey is a natural product known for its varied biological or pharmacological activities—ranging from anti-inflammatory, antioxidant, antibacterial, antihypertensive to hypoglycemic effects. This review article focuses on the role of honey in modulating the development and progression of tumors or cancers. It reviews available evidence (some of which is very recent with regards to the antimetastatic, antiproliferative and anticancer effects of honey in various forms of cancer. These effects of honey have been thoroughly investigated in certain cancers such as breast, liver and colorectal cancer cell lines. In contrast, limited but promising data are available for other forms of cancers including prostate, bladder, endometrial, kidney, skin, cervical, oral and bone cancer cells. The article also underscores the various possible mechanisms by which honey may inhibit growth and proliferation of tumors or cancers. These include regulation of cell cycle, activation of mitochondrial pathway, induction of mitochondrial outer membrane permeabilization, induction of apoptosis, modulation of oxidative stress, amelioration of inflammation, modulation of insulin signaling and inhibition of angiogenesis. Honey is highly cytotoxic against tumor or cancer cells while it is non-cytotoxic to normal cells. The data indicate that honey can inhibit carcinogenesis by modulating the molecular processes of initiation, promotion, and progression stages. Thus, it may serve as a potential and promising anticancer agent which warrants further experimental and clinical studies.

  11. Molecular dynamics simulation of nanocrystalline nickel: structure and mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Swygenhoven, H. van [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Caro, A. [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

    1997-09-01

    Molecular dynamics computer simulations of low temperature elastic and plastic deformation of Ni nanophase samples (3-7 nm) are performed. The samples are polycrystals nucleated from different seeds, with random locations and orientations. Bulk and Young`s modulus, onset of plastic deformation and mechanism responsible for the plastic behaviour are studied and compared with the behaviour of coarse grained samples. (author) 1 fig., 3 refs.

  12. Molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis clinical isolates

    OpenAIRE

    Meng Dong-Ya; Sun Chang-Jian; Yu Jing-Bo; Ma Jun; Xue Wen-Cheng

    2014-01-01

    To evaluate the molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis (MH) clinical strains isolated from urogenital specimens. 15 MH clinical isolates with different phenotypes of resistance to fluoroquinolones antibiotics were screened for mutations in the quinolone resistance-determining regions (QRDRs) of DNA gyrase (gyrA and gyrB) and topoisomerase IV (parC and parE) in comparison with the reference strain PG21, which is susceptible to fluoroquinolones antibiotics. 15 ...

  13. Molecular mechanism of signaling by tumor necrosis factor

    Institute of Scientific and Technical Information of China (English)

    ZHA; Jikun(查纪坤); SHU; Hongbing(舒红兵)

    2002-01-01

    Tumor necrosis factor (TNF) is an important cytokine with multiple biological effects,including cell growth,differentiation,apoptosis,immune regulation and induction of inflammation. The effects of TNF are mediated by two receptors,TNF-R1 and TNF-R2. The major signal transduction pathways triggered by TNF include those that lead to apoptosis,activation of transcription factor NF-??B and protein kinase JNK. This review will discuss the molecular mechanisms of these signaling pathways.

  14. Molecular mechanisms in muscular dystrophy: a gene expression profiling study.

    OpenAIRE

    Turk, Rolf

    2006-01-01

    The muscular dystrophies are a group of neuromuscular disorders characterized by progres¬sive muscle weakness and wasting. Although the underlying genetic defects of a large number of muscular dystrophies are now know, the molecular mechanisms resulting in the devastating effects of the disease are not yet clear. Furthermore, the muscular dystrophies differ in clinical presentation and severity. The processes responsible for this di¬vergence are largely unknown as well. In this thesis, gene e...

  15. Overcoming ABC transporter-mediated multidrug resistance: Molecular mechanisms and novel therapeutic drug strategies.

    Science.gov (United States)

    Li, Wen; Zhang, Han; Assaraf, Yehuda G; Zhao, Kun; Xu, Xiaojun; Xie, Jinbing; Yang, Dong-Hua; Chen, Zhe-Sheng

    2016-07-01

    Multidrug resistance is a key determinant of cancer chemotherapy failure. One of the major causes of multidrug resistance is the enhanced efflux of drugs by membrane ABC transporters. Targeting ABC transporters projects a promising approach to eliminating or suppressing drug resistance in cancer treatment. To reveal the functional mechanisms of ABC transporters in drug resistance, extensive studies have been conducted from identifying drug binding sites to elucidating structural dynamics. In this review article, we examined the recent crystal structures of ABC proteins to depict the functionally important structural elements, such as domains, conserved motifs, and critical amino acids that are involved in ATP-binding and drug efflux. We inspected the drug-binding sites on ABC proteins and the molecular mechanisms of various substrate interactions with the drug binding pocket. While our continuous battle against drug resistance is far from over, new approaches and technologies have emerged to push forward our frontier. Most recent developments in anti-MDR strategies include P-gp inhibitors, RNA-interference, nano-medicines, and delivering combination strategies. With the advent of the 'Omics' era - genomics, epigenomics, transcriptomics, proteomics, and metabolomics - these disciplines play an important role in fighting the battle against chemoresistance by further unraveling the molecular mechanisms of drug resistance and shed light on medical therapies that specifically target MDR. PMID:27449595

  16. Molecular mechanism of abnormal aggregation of α-synuclein

    Institute of Scientific and Technical Information of China (English)

    HU HongYua; LIN XiaoJing

    2007-01-01

    The abnormal aggregation of α-synuclein (α-Syn) is thought to be closely associated with Parkinson's disease, but the pathogenesis is still unclear. In this review, we survey the latest development in the molecular mechanism of abnormal α-Syn aggregation, especially in the aspects of the core sequences, aggregation inhibitors, structural transformation and filament morphologies. By exploring the mechanism of α-Syn aggregation, we will have a better understanding of the disease pathogenesis, and develop strategies for preventing and treating this severe disease.

  17. Underlying molecular and cellular mechanisms in childhood irritable bowel syndrome.

    Science.gov (United States)

    Chumpitazi, Bruno P; Shulman, Robert J

    2016-12-01

    Irritable bowel syndrome (IBS) affects a large number of children throughout the world. The symptom expression of IBS is heterogeneous, and several factors which may be interrelated within the IBS biopsychosocial model play a role. These factors include visceral hyperalgesia, intestinal permeability, gut microbiota, psychosocial distress, gut inflammation, bile acids, food intolerance, colonic bacterial fermentation, and genetics. The molecular and cellular mechanisms of these factors are being actively investigated. In this mini-review, we present updates of these mechanisms and, where possible, relate the findings to childhood IBS. Mechanistic elucidation may lead to the identification of biomarkers as well as personalized childhood IBS therapies. PMID:26883355

  18. Mechanisms of ventricular arrhythmias: from molecular fluctuations to electrical turbulence.

    Science.gov (United States)

    Qu, Zhilin; Weiss, James N

    2015-01-01

    Ventricular arrhythmias have complex causes and mechanisms. Despite extensive investigation involving many clinical, experimental, and computational studies, effective biological therapeutics are still very limited. In this article, we review our current understanding of the mechanisms of ventricular arrhythmias by summarizing the state of knowledge spanning from the molecular scale to electrical wave behavior at the tissue and organ scales and how the complex nonlinear interactions integrate into the dynamics of arrhythmias in the heart. We discuss the challenges that we face in synthesizing these dynamics to develop safe and effective novel therapeutic approaches. PMID:25340965

  19. Molecular simulation of the reversible mechanical unfolding of proteins.

    Science.gov (United States)

    Rathore, Nitin; Yan, Qiliang; de Pablo, Juan J

    2004-03-22

    In this work we have combined a Wang-Landau sampling scheme [F. Wang and D. Landau, Phys. Rev. Lett. 86, 2050 (2001)] with an expanded ensemble formalism to yield a simple and powerful method for computing potentials of mean force. The new method is implemented to investigate the mechanical deformation of proteins. Comparisons are made with analytical results for simple model systems such as harmonic springs and Rouse chains. The method is then illustrated on a model 15-residue alanine molecule in an implicit solvent. Results for mechanical unfolding of this oligopeptide are compared to those of steered molecular dynamics calculations.

  20. Simulated scaling method for localized enhanced sampling and simultaneous "alchemical" free energy simulations: a general method for molecular mechanical, quantum mechanical, and quantum mechanical/molecular mechanical simulations.

    Science.gov (United States)

    Li, Hongzhi; Fajer, Mikolai; Yang, Wei

    2007-01-14

    A potential scaling version of simulated tempering is presented to efficiently sample configuration space in a localized region. The present "simulated scaling" method is developed with a Wang-Landau type of updating scheme in order to quickly flatten the distributions in the scaling parameter lambdam space. This proposal is meaningful for a broad range of biophysical problems, in which localized sampling is required. Besides its superior capability and robustness in localized conformational sampling, this simulated scaling method can also naturally lead to efficient "alchemical" free energy predictions when dual-topology alchemical hybrid potential is applied; thereby simultaneously, both of the chemically and conformationally distinct portions of two end point chemical states can be efficiently sampled. As demonstrated in this work, the present method is also feasible for the quantum mechanical and quantum mechanical/molecular mechanical simulations.

  1. Cardiovascular effects of cocaine: cellular, ionic and molecular mechanisms.

    Science.gov (United States)

    Turillazzi, E; Bello, S; Neri, M; Pomara, C; Riezzo, I; Fineschi, V

    2012-01-01

    Cocaine is a widely abused drug responsible for the majority of deaths ascribed to drug overdose. Many mechanisms have been proposed in order to explain the various cocaine associated cardiovascular complications. Conventionally, cocaine cardiotoxicity has been thought to be mediated indirectly through its sympathomimetic effect, i.e., by inhibiting the reuptake and thus increasing the levels of neuronal catecholamines at work on adrenoceptors. Increased oxidative stress, reactive oxygen species, and cocaine-induced apoptosis in the heart muscle have suggested a new way to understand the cardiotoxic effects of cocaine. More recent studies have led the attention to the interaction of cocaine and some metabolites with cardiac sodium, calcium and potassium channels. The current paper is aimed to investigate the molecular mechanisms of cocaine cardiotoxicity which have a specific clinical and forensic interest. From a clinical point of view the full knowledge of the exact mechanisms by which cocaine exerts cardio - vascular damage is essential to identify potential therapeutic targets and improve novel strategies for cocaine related cardiovascular diseases. From a forensic point of view, it is to be underlined that cocaine use is often associated to sudden death in young, otherwise healthy individuals. While such events are widely reported, the relationship between cardiac morphological alterations and molecular/cellular mechanisms is still controversial. In conclusion, the study of cocaine cardiovascular toxicity needs a strict collaboration between clinicians and pathologists which may be very effective in further dissecting the mechanisms underlying cocaine cardiotoxicity and understanding the cardiac cocaine connection. PMID:22856657

  2. Breast cancer molecular subtypes: from TNBC to QNBC

    Science.gov (United States)

    Hon, Jane Date C; Singh, Baljit; Sahin, Aysegul; Du, Gang; Wang, Jinhua; Wang, Vincent Y; Deng, Fang-Ming; Zhang, David Y; Monaco, Marie E; Lee, Peng

    2016-01-01

    Treatment protocols for breast cancer depend predominantly on receptor status with respect to estrogen (estrogen receptor alpha), progesterone (progesterone receptor) and human epidermal growth factor [human epidermal growth factor receptor 2 (HER2)]. The presence of one or more of these receptors suggests that a treatment targeting these pathways might be effective, while the absence of, or in the case of HER2, lack of overexpression of, all of these receptors, termed triple negative breast cancer (TNBC), indicates a need for the more toxic chemotherapy. In an effort to develop targeted therapies for TNBC, it will be necessary to differentiate among specific TNBC subtypes. The subset of TNBC that expresses androgen receptor (AR) has been determined to express genes consistent with a luminal subtype and therefore may be amenable to therapies targeting either AR, itself, or other pathways typical of a luminal subtype. Recent investigations of the AR signal pathway within breast cancer lead to AR as a significant target for breast cancer therapy with several clinical trials currently in progress. The subclass of TNBC that lacks AR, which we have termed quadruple negative breast cancer (QNBC) currently lacks a defined targetable pathway. Unlike AR-positive TNBC, QNBC predominantly exhibits a basal-like molecular subtype. Several subtypes and related pathway proteins are preferentially expressed in QNBC that may serve as effective targets for treatment, such as ACSL4, SKP2 and EGFR. ACSL4 expression has been demonstrated to be inversely correlated with expression of hormone/growth factor receptors and may thus serve as a biomarker for QNBC as well as a target for therapy. In the following review we summarize some of the current efforts to develop alternatives to chemotherapy for TNBC and QNBC.

  3. Obesity-related colon cancer: dietary factors and their mechanisms of anticancer action.

    Science.gov (United States)

    Zeng, Huawei; Lazarova, Darina L

    2012-02-01

    Overweight/obesity is an epidemic in the US as well as in other developed countries, affecting two-thirds of Americans and an estimated 2.3 billion people worldwide. Obesity increases the risk for Type 2 diabetes, cardiovascular disease and cancer. For example, epidemiological studies have established a strong association between obesity and colon cancer. It is generally accepted that metabolic changes associated with overweight/obesity, particularly abdominal obesity and changes in adipocyte function, contribute to the increased risk of colon cancer. Understanding the mechanisms underlying this association is important for the development of preventive strategies for colon cancer. Part of these preventive strategies may be based on dietary factors, such as vitamins, minerals (e.g. selenium), fibre, phytochemicals and phenolic compounds. These anticancer nutrients may counteract the molecular changes associated with obesity. The present article reviews the evidence that inflammation and insulin resistance induced by obesity are the molecular mediators of the association between obesity and colon cancer. We also evaluate the evidence for the ability of dietary factors to target the obesity-induced changes and, thus, protect against colon cancer.

  4. Genomic and molecular mechanisms for efficient biodegradation of aromatic dye.

    Science.gov (United States)

    Sun, Su; Xie, Shangxian; Chen, Hu; Cheng, Yanbing; Shi, Yan; Qin, Xing; Dai, Susie Y; Zhang, Xiaoyu; Yuan, Joshua S

    2016-01-25

    Understanding the molecular mechanisms for aromatic compound degradation is crucial for the development of effective bioremediation strategies. We report the discovery of a novel phenomenon for improved degradation of Direct Red 5B azo dye by Irpex lacteus CD2 with lignin as a co-substrate. Transcriptomics analysis was performed to elucidate the molecular mechanisms of aromatic degradation in white rot fungus by comparing dye, lignin, and dye/lignin combined treatments. A full spectrum of lignin degradation peroxidases, oxidases, radical producing enzymes, and other relevant components were up-regulated under DR5B and lignin treatments. Lignin induced genes complemented the DR5B induced genes to provide essential enzymes and redox conditions for aromatic compound degradation. The transcriptomics analysis was further verified by manganese peroxidase (MnP) protein over-expression, as revealed by proteomics, dye decolorization assay by purified MnP and increased hydroxyl radical levels, as indicated by an iron reducing activity assay. Overall, the molecular and genomic mechanisms indicated that effective aromatic polymer degradation requires synergistic enzymes and radical-mediated oxidative reactions to form an effective network of chemical processes. This study will help to guide the development of effective bioremediation and biomass degradation strategies. PMID:26476316

  5. Genomic and molecular mechanisms for efficient biodegradation of aromatic dye.

    Science.gov (United States)

    Sun, Su; Xie, Shangxian; Chen, Hu; Cheng, Yanbing; Shi, Yan; Qin, Xing; Dai, Susie Y; Zhang, Xiaoyu; Yuan, Joshua S

    2016-01-25

    Understanding the molecular mechanisms for aromatic compound degradation is crucial for the development of effective bioremediation strategies. We report the discovery of a novel phenomenon for improved degradation of Direct Red 5B azo dye by Irpex lacteus CD2 with lignin as a co-substrate. Transcriptomics analysis was performed to elucidate the molecular mechanisms of aromatic degradation in white rot fungus by comparing dye, lignin, and dye/lignin combined treatments. A full spectrum of lignin degradation peroxidases, oxidases, radical producing enzymes, and other relevant components were up-regulated under DR5B and lignin treatments. Lignin induced genes complemented the DR5B induced genes to provide essential enzymes and redox conditions for aromatic compound degradation. The transcriptomics analysis was further verified by manganese peroxidase (MnP) protein over-expression, as revealed by proteomics, dye decolorization assay by purified MnP and increased hydroxyl radical levels, as indicated by an iron reducing activity assay. Overall, the molecular and genomic mechanisms indicated that effective aromatic polymer degradation requires synergistic enzymes and radical-mediated oxidative reactions to form an effective network of chemical processes. This study will help to guide the development of effective bioremediation and biomass degradation strategies.

  6. Targeted Cancer Therapy: Vital Oncogenes and a New Molecular Genetic Paradigm for Cancer Initiation Progression and Treatment

    Science.gov (United States)

    Willis, Rudolph E.

    2016-01-01

    It has been declared repeatedly that cancer is a result of molecular genetic abnormalities. However, there has been no working model describing the specific functional consequences of the deranged genomic processes that result in the initiation and propagation of the cancer process during carcinogenesis. We no longer need to question whether or not cancer arises as a result of a molecular genetic defect within the cancer cell. The legitimate questions are: how and why? This article reviews the preeminent data on cancer molecular genetics and subsequently proposes that the sentinel event in cancer initiation is the aberrant production of fused transcription activators with new molecular properties within normal tissue stem cells. This results in the production of vital oncogenes with dysfunctional gene activation transcription properties, which leads to dysfunctional gene regulation, the aberrant activation of transduction pathways, chromosomal breakage, activation of driver oncogenes, reactivation of stem cell transduction pathways and the activation of genes that result in the hallmarks of cancer. Furthermore, a novel holistic molecular genetic model of cancer initiation and progression is presented along with a new paradigm for the approach to personalized targeted cancer therapy, clinical monitoring and cancer diagnosis. PMID:27649156

  7. Molecular structure and elastic properties of thermotropic liquid crystals: Integrated molecular dynamics—Statistical mechanical theory vs molecular field approach

    Science.gov (United States)

    Capar, M. Ilk; Nar, A.; Ferrarini, A.; Frezza, E.; Greco, C.; Zakharov, A. V.; Vakulenko, A. A.

    2013-03-01

    The connection between the molecular structure of liquid crystals and their elastic properties, which control the director deformations relevant for electro-optic applications, remains a challenging objective for theories and computations. Here, we compare two methods that have been proposed to this purpose, both characterized by a detailed molecular level description. One is an integrated molecular dynamics-statistical mechanical approach, where the bulk elastic constants of nematics are calculated from the direct correlation function (DCFs) and the single molecule orientational distribution function [D. A. McQuarrie, Statistical Mechanics (Harper & Row, New York, 1973)]. The latter is obtained from atomistic molecular dynamics trajectories, together with the radial distribution function, from which the DCF is then determined by solving the Ornstein-Zernike equation. The other approach is based on a molecular field theory, where the potential of mean torque experienced by a mesogen in the liquid crystal phase is parameterized according to its molecular surface. In this case, the calculation of elastic constants is combined with the Monte Carlo sampling of single molecule conformations. Using these different approaches, but the same description, at the level of molecular geometry and torsional potentials, we have investigated the elastic properties of the nematic phase of two typical mesogens, 4'-n-pentyloxy-4-cyanobiphenyl and 4'-n-heptyloxy-4-cyanobiphenyl. Both methods yield K3(bend) >K1 (splay) >K2 (twist), although there are some discrepancies in the average elastic constants and in their anisotropy. These are interpreted in terms of the different approximations and the different ways of accounting for the structural properties of molecules in the two approaches. In general, the results point to the role of the molecular shape, which is modulated by the conformational freedom and cannot be fully accounted for by a single descriptor such as the aspect ratio.

  8. Molecular structure and elastic properties of thermotropic liquid crystals: integrated molecular dynamics--statistical mechanical theory vs molecular field approach.

    Science.gov (United States)

    Ilk Capar, M; Nar, A; Ferrarini, A; Frezza, E; Greco, C; Zakharov, A V; Vakulenko, A A

    2013-03-21

    The connection between the molecular structure of liquid crystals and their elastic properties, which control the director deformations relevant for electro-optic applications, remains a challenging objective for theories and computations. Here, we compare two methods that have been proposed to this purpose, both characterized by a detailed molecular level description. One is an integrated molecular dynamics-statistical mechanical approach, where the bulk elastic constants of nematics are calculated from the direct correlation function (DCFs) and the single molecule orientational distribution function [D. A. McQuarrie, Statistical Mechanics (Harper & Row, New York, 1973)]. The latter is obtained from atomistic molecular dynamics trajectories, together with the radial distribution function, from which the DCF is then determined by solving the Ornstein-Zernike equation. The other approach is based on a molecular field theory, where the potential of mean torque experienced by a mesogen in the liquid crystal phase is parameterized according to its molecular surface. In this case, the calculation of elastic constants is combined with the Monte Carlo sampling of single molecule conformations. Using these different approaches, but the same description, at the level of molecular geometry and torsional potentials, we have investigated the elastic properties of the nematic phase of two typical mesogens, 4'-n-pentyloxy-4-cyanobiphenyl and 4'-n-heptyloxy-4-cyanobiphenyl. Both methods yield K3(bend) >K1 (splay) >K2 (twist), although there are some discrepancies in the average elastic constants and in their anisotropy. These are interpreted in terms of the different approximations and the different ways of accounting for the structural properties of molecules in the two approaches. In general, the results point to the role of the molecular shape, which is modulated by the conformational freedom and cannot be fully accounted for by a single descriptor such as the aspect ratio

  9. Molecular profiling of multiple human cancers defines an inflammatory cancer-associated molecular pattern and uncovers KPNA2 as a uniform poor prognostic cancer marker.

    Directory of Open Access Journals (Sweden)

    Saleh M Rachidi

    Full Text Available BACKGROUND: Immune evasion is one of the recognized hallmarks of cancer. Inflammatory responses to cancer can also contribute directly to oncogenesis. Since the immune system is hardwired to protect the host, there is a possibility that cancers, regardless of their histological origins, endow themselves with a common and shared inflammatory cancer-associated molecular pattern (iCAMP to promote oncoinflammation. However, the definition of iCAMP has not been conceptually and experimentally investigated. METHODS AND FINDINGS: Genome-wide cDNA expression data was analyzed for 221 normal and 324 cancer specimens from 7 cancer types: breast, prostate, lung, colon, gastric, oral and pancreatic. A total of 96 inflammatory genes with consistent dysregulation were identified, including 44 up-regulated and 52 down-regulated genes. Protein expression was confirmed by immunohistochemistry for some of these genes. The iCAMP contains proteins whose roles in cancer have been implicated and others which are yet to be appreciated. The clinical significance of many iCAMP genes was confirmed in multiple independent cohorts of colon and ovarian cancer patients. In both cases, better prognosis correlated strongly with high CXCL13 and low level of GREM1, LOX, TNFAIP6, CD36, and EDNRA. An "Inflammatory Gene Integrated Score" was further developed from the combination of 18 iCAMP genes in ovarian cancer, which predicted overall survival. Noticeably, as a selective nuclear import protein whose immuno-regulatory function just begins to emerge, karyopherin alpha 2 (KPNA2 is uniformly up-regulated across cancer types. For the first time, the cancer-specific up-regulation of KPNA2 and its clinical significance were verified by tissue microarray analysis in colon and head-neck cancers. CONCLUSION: This work defines an inflammatory signature shared by seven epithelial cancer types and KPNA2 as a consistently up-regulated protein in cancer. Identification of iCAMP may not only

  10. Breast Cancer Genetic and Molecular Subtype Impacts Response to Omega-3 Fatty Acid Ethyl Esters.

    Science.gov (United States)

    Chen, Ching Hui; Fabian, Carol; Hursting, Stephen; deGraffenried, Linda A

    2016-01-01

    Epidemiological studies have correlated frequent omega-3 (n-3) fatty acid consumption with a lower risk for breast cancer; however, recent prospective studies have been less conclusive. Efforts in the preventive setting have focused on the use of n-3 fatty acids, and the pharmaceutical ethyl esters (EE) of these natural compounds, for high-risk patient populations. Limited understanding of specific mechanisms by which these agents function has hampered identification of the cancer subtype(s) that would gain the greatest therapeutic benefit. In this study, we investigated the in vitro effects of n-3 EEs in four distinct breast cancer subtypes and explored how they affect not only breast cancer cell survival but also modulate the nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB) and peroxisome proliferator-activated receptor gamma signaling pathways. Similar to the high variance in response observed in human studies, we found that the effectiveness of n-3 EEs depends on the molecular characteristics of the MCF-7, CAMA-1, MDA-MB-231, and SKBR3 breast cancer cell lines and is closely associated with the suppression of NF-κB. These data strongly suggest that the use of n-3 fatty acids and their pharmaceutical ether esters in the prevention and therapeutic setting should be guided by specific tumor characteristics. PMID:27367296

  11. Molecular mechanisms of breast cancer metastasis mediated by chemokine CXCL12 and it's receptor CXCR4%趋化因子CXCL12及其受体CXCR4介导乳腺癌转移分子机制

    Institute of Scientific and Technical Information of China (English)

    李瑞杰; 樊青霞

    2009-01-01

    The interaction of CXCL12 and CXCR4 has a pivotal role in breast cancer metastasis. Re- cent studies have identified that the metastasis of breast cancer mediated by CXCL-12-CXCR4 is associated with HIF-1、Her-2、NF-κB、and uPAR. We should determine the molecular mechanisms as soon as possible,and then block the function of up- stream molecules, exploit new anti- metastatic drugs. These developments will be translated into significant survival benefits for patients.%趋化因子CXCL12及其受体CXCR4之间的相互作用在乳腺癌转移中起着枢轴作用.新近研究发现,CXCR4-CXCL12介导的乳腺癌转移与缺氧诱导因子-1(HIF-1)、Her-2、核因子-κB(NFκB)、尿激酶型纤维蛋白酶原激活剂受体(uPAR)等分子密切相关,明确CXCL12-CXCR4介导的乳腺癌转移分子机制,进而逐个阻断上游分子对二者的调控作用,开发出靶点明确、作用特异的抗转移药物将使乳腺癌患者获益.

  12. Cancer Cachexia:Mechanisms and Clinical Implications

    OpenAIRE

    Donohoe, Claire L.; Ryan, Aoife M.; John V. Reynolds

    2011-01-01

    PUBLISHED Cachexia is amultifactorial process of skeletal muscle and adipose tissue atrophy resulting in progressive weight loss. It is associated with poor quality of life, poor physical function, and poor prognosis in cancer patients. It involves multiple pathways: procachectic and proinflammatory signals from tumour cells, systemic inflammation in the host, and widespread metabolic changes (increased resting energy expenditure and alterations in metabolism of protein, fat, and ...

  13. Molecular targeted treatment and radiation therapy for rectal cancer

    International Nuclear Information System (INIS)

    Background: EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols. Material and methods: cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings. Results: the combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low rates of pathologic complete remission have been noted in several phase II studies. The K-ras mutation status and the gene copy number of EGFR may predict tumor response. The toxicity pattern (radiation-induced enteritis, perforations) and surgical complications (wound healing, fistula, bleeding) observed in at least some of the clinical studies with bevacizumab and CRT warrant further investigations. Conclusion: longer follow-up (and, finally, randomized trials) is needed to draw any firm conclusions with respect to local and distant failure rates, and toxicity associated with these novel treatment approaches. (orig.)

  14. Molecular targeted treatment and radiation therapy for rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Marquardt, Friederike; Roedel, Franz; Capalbo, Gianni; Weiss, Christian; Roedel, Claus [Dept. of Radiation Therapy, Univ. of Frankfurt/Main (Germany)

    2009-06-15

    Background: EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols. Material and methods: cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings. Results: the combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low rates of pathologic complete remission have been noted in several phase II studies. The K-ras mutation status and the gene copy number of EGFR may predict tumor response. The toxicity pattern (radiation-induced enteritis, perforations) and surgical complications (wound healing, fistula, bleeding) observed in at least some of the clinical studies with bevacizumab and CRT warrant further investigations. Conclusion: longer follow-up (and, finally, randomized trials) is needed to draw any firm conclusions with respect to local and distant failure rates, and toxicity associated with these novel treatment approaches. (orig.)

  15. A mechanically-induced colon cancer cell population shows increased metastatic potential

    KAUST Repository

    Tang, Xin

    2014-05-29

    Background: Metastasis accounts for the majority of deaths from cancer. Although tumor microenvironment has been shown to have a significant impact on the initiation and/or promotion of metastasis, the mechanism remains elusive. We previously reported that HCT-8 colon cancer cells underwent a phenotypic transition from an adhesive epithelial type (E-cell) to a rounded dissociated type (R-cell) via soft substrate culture, which resembled the initiation of metastasis. The objective of current study was to investigate the molecular and metabolic mechanisms of the E-R transition.Methods: Global gene expressions of HCT-8 E and R cells were measured by RNA Sequencing (RNA-seq); and the results were further confirmed by real-time PCR. Reactive oxygen species (ROS), anoikis resistance, enzyme activity of aldehyde dehydrogenase 3 family, member A1 (ALDH3A1), and in vitro invasion assay were tested on both E and R cells. The deformability of HCT-8 E and R cells was measured by atomic force microscopy (AFM). To study the in vivo invasiveness of two cell types, athymic nude mice were intra-splenically injected with HCT-8 E or R cells and sacrificed after 9 weeks. Incidences of tumor development and metastasis were histologically evaluated and analyzed with Fisher\\'s exact test.Results: Besides HCT-8, E-R transition on soft substrates was also seen in three other cancer cell lines (HCT116, SW480 colon and DU145 prostate cancer). The expression of some genes, such as ALDH3A1, TNS4, CLDN2, and AKR1B10, which are known to play important roles in cancer cell migration, invasion, proliferation and apoptosis, were increased in HCT-8 R cells. R cells also showed higher ALDH3A1 enzyme activity, higher ROS, higher anoikis resistance, and higher softness than E cells. More importantly, in vitro assay and in vivo animal models revealed that HCT-8 R cells were more invasive than E cells.Conclusions: Our comprehensive comparison of HCT-8 E and R cells revealed differences of molecular

  16. Nuclear EGFR as a molecular target in cancer

    International Nuclear Information System (INIS)

    The epidermal growth factor receptor (EGFR) has been one of the most targeted receptors in the field of oncology. While anti-EGFR inhibitors have demonstrated clinical success in specific cancers, most patients demonstrate either intrinsic or acquired resistance within one year of treatment. Many mechanisms of resistance to EGFR inhibitors have been identified, one of these being attributed to alternatively localized EGFR from the cell membrane into the cell’s nucleus. Inside the nucleus, EGFR functions as a co-transcription factor for several genes involved in cell proliferation and angiogenesis, and as a tyrosine kinase to activate and stabilize proliferating cell nuclear antigen and DNA dependent protein kinase. Nuclear localized EGFR is highly associated with disease progression, worse overall survival in numerous cancers, and enhanced resistance to radiation, chemotherapy, and the anti-EGFR therapies gefitinib and cetuximab. In this review the current knowledge of how nuclear EGFR enhances resistance to cancer therapeutics is discussed, in addition to highlighting ways to target nuclear EGFR as an anti-cancer strategy in the future

  17. RNA profiling reveals familial aggregation of molecular subtypes in non-BRCA1/2 breast cancer families

    DEFF Research Database (Denmark)

    Larsen, Martin J; Thomassen, Mads; Tan, Qihua;

    2014-01-01

    BACKGROUND: In more than 70% of families with a strong history of breast and ovarian cancers, pathogenic mutation in BRCA1 or BRCA2 cannot be identified, even though hereditary factors are expected to be involved. It has been proposed that tumors with similar molecular phenotypes also share similar...... underlying pathophysiological mechanisms. In the current study, the aim was to investigate if global RNA profiling can be used to identify functional subgroups within breast tumors from families tested negative for BRCA1/2 germline mutations and how these subgroupings relate to different breast cancer...... cancer subtypes, exist among non-BRCA1/2 breast cancers. The distribution of subtypes was markedly different from the distribution found among BRCA1/2 mutation carriers. From 11 breast cancer families, breast tumor biopsies from more than one affected family member were included in the study. Notably...

  18. Functions and mechanisms of long noncoding RNAs in lung cancer

    Directory of Open Access Journals (Sweden)

    Peng ZZ

    2016-07-01

    Full Text Available Zhenzi Peng, Chunfang Zhang, Chaojun Duan Institute of Medical Sciences, Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, People’s Republic of China Abstract: Lung cancer is a heterogeneous disease, and there is a lack of adequate biomarkers for diagnosis. Long noncoding RNAs (lncRNAs are emerging as an important set of molecules because of their roles in various key pathophysiological pathways, including cell growth, apoptosis, and metastasis. We review the current knowledge of the lncRNAs in lung cancer. In-depth analyses of lncRNAs in lung cancer have increased the number of potential effective biomarkers, thus providing options to increase the therapeutic benefit. In this review, we summarize the functions, mechanisms, and regulatory networks of lncRNAs in lung cancer, providing a basis for further research in this field. Keywords: ncRNA, tumorigenesis, biomarker, network, proliferation, apoptosis 

  19. Physiological, Molecular and Genetic Mechanisms of Long-Term Habituation

    Energy Technology Data Exchange (ETDEWEB)

    Calin-Jageman, Robert J

    2009-09-12

    Work funded on this grant has explored the mechanisms of long-term habituation, a ubiquitous form of learning that plays a key role in basic cognitive functioning. Specifically, behavioral, physiological, and molecular mechanisms of habituation have been explored using a simple model system, the tail-elicited siphon-withdrawal reflex (T-SWR) in the marine mollusk Aplysia californica. Substantial progress has been made on the first and third aims, providing some fundamental insights into the mechanisms by which memories are stored. We have characterized the physiological correlates of short- and long-term habituation. We found that short-term habituation is accompanied by a robust sensory adaptation, whereas long-term habituation is accompanied by alterations in sensory and interneuron synaptic efficacy. Thus, our data indicates memories can be shifted between different sites in a neural network as they are consolidated from short to long term. At the molecular level, we have accomplished microarray analysis comparing gene expression in both habituated and control ganglia. We have identified a network of putatively regulated transcripts that seems particularly targeted towards synaptic changes (e.g. SNAP25, calmodulin) . We are now beginning additional work to confirm regulation of these transcripts and build a more detailed understanding of the cascade of molecular events leading to the permanent storage of long-term memories. On the third aim, we have fostered a nascent neuroscience program via a variety of successful initiatives. We have funded over 11 undergraduate neuroscience scholars, several of whom have been recognized at national and regional levels for their research. We have also conducted a pioneering summer research program for community college students which is helping enhance access of underrepresented groups to life science careers. Despite minimal progress on the second aim, this project has provided a) novel insight into the network mechanisms by

  20. Molecular mechanisms of foliar water uptake in a desert tree.

    Science.gov (United States)

    Yan, Xia; Zhou, Maoxian; Dong, Xicun; Zou, Songbing; Xiao, Honglang; Ma, Xiao-Fei

    2015-01-01

    Water deficits severely affect growth, particularly for the plants in arid and semiarid regions of the world. In addition to precipitation, other subsidiary water, such as dew, fog, clouds and small rain showers, may also be absorbed by leaves in a process known as foliar water uptake. With the severe scarcity of water in desert regions, this process is increasingly becoming a necessity. Studies have reported on physical and physiological processes of foliar water uptake. However, the molecular mechanisms remain less understood. As major channels for water regulation and transport, aquaporins (AQPs) are involved in this process. However, due to the regulatory complexity and functional diversity of AQPs, their molecular mechanism for foliar water uptake remains unclear. In this study, Tamarix ramosissima, a tree species widely distributed in desert regions, was investigated for gene expression patterns of AQPs and for sap flow velocity. Our results suggest that the foliar water uptake of T. ramosissima occurs in natural fields at night when the humidity is over a threshold of 85 %. The diurnal gene expression pattern of AQPs suggests that most AQP gene expressions display a circadian rhythm, and this could affect both photosynthesis and transpiration. At night, the PIP2-1 gene is also upregulated with increased relative air humidity. This gene expression pattern may allow desert plants to regulate foliar water uptake to adapt to extreme drought. This study suggests a molecular basis of foliar water uptake in desert plants. PMID:26567212

  1. Molecular mechanisms of IgE mediated food allergy.

    Science.gov (United States)

    Kumar, Sandeep; Verma, Alok Kumar; Das, Mukul; Dwivedi, Premendra D

    2012-08-01

    The purpose of this review is to collate current knowledge and recent advances in molecular mechanism behind the immediate type hypersensitivity of foods. Food allergy is a growing concern of human health in developed as well as developing countries now days. Food allergic reactions are mostly IgE mediated and also known as immediate type hypersensitivity or type I reaction. This review encompasses a wide range of molecular events during IgE mediated reactions like primary exposure of allergens, processing of allergens by antigen presenting cells, role of transcription factors like GATA-3, STAT-6, NF-AT, c-maf, c-kit and NF-κB, Treg cells, toll like receptors, cytokines and chemokines, class switch to IgE, FcεR1 receptor, priming of IgE on mast cells or basophils, signaling events followed by secondary exposure of allergens, degranulation and release of mediators like leukotrienes, histamines, prostaglandins, β-hexosaminidase and ultimately anaphylaxis. This review may be helpful to beginners as well as experts working in the field of allergy and immunology because of the stepwise explanations of molecular mechanisms involved in IgE mediated reactions. PMID:22668720

  2. Studies on the molecular mechanisms of seed germination.

    Science.gov (United States)

    Han, Chao; Yang, Pingfang

    2015-05-01

    Seed germination that begins with imbibition and ends with radicle emergence is the first step for plant growth. Successful germination is not only crucial for seedling establishment but also important for crop yield. After being dispersed from mother plant, seed undergoes continuous desiccation in ecosystem and selects proper environment to trigger germination. Owing to the contribution of transcriptomic, proteomic, and molecular biological studies, molecular aspect of seed germination is elucidated well in Arabidopsis. Recently, more and more proteomic and genetic studies concerning cereal seed germination were performed on rice (Oryza sativa) and barley (Hordeum vulgare), which possess completely different seed structure and domestication background with Arabidopsis. In this review, both the common features and the distinct mechanisms of seed germination are compared among different plant species including Arabidopsis, rice, and maize. These features include morphological changes, cell and its related structure recovery, metabolic activation, hormone behavior, and transcription and translation activation. This review will provide more comprehensive insights into the molecular mechanisms of seed germination. PMID:25597791

  3. Studies on the molecular mechanisms of seed germination.

    Science.gov (United States)

    Han, Chao; Yang, Pingfang

    2015-05-01

    Seed germination that begins with imbibition and ends with radicle emergence is the first step for plant growth. Successful germination is not only crucial for seedling establishment but also important for crop yield. After being dispersed from mother plant, seed undergoes continuous desiccation in ecosystem and selects proper environment to trigger germination. Owing to the contribution of transcriptomic, proteomic, and molecular biological studies, molecular aspect of seed germination is elucidated well in Arabidopsis. Recently, more and more proteomic and genetic studies concerning cereal seed germination were performed on rice (Oryza sativa) and barley (Hordeum vulgare), which possess completely different seed structure and domestication background with Arabidopsis. In this review, both the common features and the distinct mechanisms of seed germination are compared among different plant species including Arabidopsis, rice, and maize. These features include morphological changes, cell and its related structure recovery, metabolic activation, hormone behavior, and transcription and translation activation. This review will provide more comprehensive insights into the molecular mechanisms of seed germination.

  4. Molecular cytotoxicity mechanisms of allyl alcohol (acrolein) in budding yeast.

    Science.gov (United States)

    Golla, Upendarrao; Bandi, Goutham; Tomar, Raghuvir S

    2015-06-15

    Allyl alcohol (AA) is one of the environmental pollutants used as a herbicide and industrial chemical. AA undergoes enzymatic oxidation in vivo to form Acrolein (Acr), a highly reactive and ubiquitous environmental toxicant. The exposure to AA/Acr has detrimental effects on cells and is highly fatal. In corroboration to the current literature describing AA/Acr toxicity, this study aimed to investigate the molecular cytotoxicity mechanisms of AA/Acr using budding yeast as a eukaryotic model organism. Genome-wide transcriptome analysis of cells treated with a sublethal dose of AA (0.4 mM) showed differential regulation of approximately 30% of the yeast genome. Functional enrichment analysis of the AA transcriptome revealed that genes belong to diverse cellular processes including the cell cycle, DNA damage repair, metal homeostasis, stress response genes, ribosomal biogenesis, metabolism, meiosis, ubiquitination, cell morphogenesis, and transport. Moreover, we have identified novel molecular targets of AA/Acr through genetic screening, which belongs to oxidative stress, DNA damage repair, iron homeostasis, and cell wall integrity. This study also demonstrated the epigenetic basis of AA/Acr toxicity mediated through histone tails and chromatin modifiers. Interestingly, our study disclosed the use of pyrazole and ethanol as probable antidotes for AA intoxication. For the first time, this study also demonstrated the reproductive toxicity of AA/Acr using the yeast gametogenesis (spermatogenesis) model. Altogether, this study unravels the molecular mechanisms of AA/Acr cytotoxicity and facilitates the prediction of biomarkers for toxicity assessment and therapeutic approaches. PMID:25919230

  5. Growth Inhibition and Apoptosis Inducing Mechanisms of Curcumin on Human Ovarian Cancer Cell Line A2780

    Institute of Scientific and Technical Information of China (English)

    ZHENG Li-duan; TONG Qiang-song; WU Cui-huan

    2006-01-01

    Objective: To explore the growth inhibition effects and apoptosis inducing mechanisms of curcumin on human ovarian cancer cell line A2780. Methods: After treatment with 10-50 μmol/L curcumin for 6-24 h, the growth activity of A2780 cancer cells were studied by [ 4, 5-dimethylthiazol-2-yl]-2, 5-diphenyItetrazolium bromide (MTT) colorimetry. Cellular apoptosis was inspected by flow cytometery and acridine orange-ethidium bromide fluorescent staining methods. The fragmentation of cellular chromosome DNA was detected by DNA ladder, the ultrastructural change was observed under a transmission electron microscope,and the protein levels of nuclear factor-kappa B (NF-κB, P65) and cysteinyl aspartate specific protease-3 (Caspase-3) in ovarian cancer cells were measured by immunohistochemistry. Results: After treatment with various concentrations of curcumin, the growth inhibition rates of cancer cells reached 62.05%- 89.24%,with sub-G1 peaks appearing on histogram. Part of the cancer cells showed characteristic morphological changes of apoptosis under fluorescence and electron microscopes, and the rate of apoptosis was 21.5 % -33.5%. The protein expression of NF-κB was decreased, while that of Caspase-3 was increased in a timedependent manner. Conclusion: Curcumin could significantly inhibit the growth of human ovarian cancer cells;inducing apoptosis through up-regulating Caspase-3 and down-regulating gene expression of NF-κB is probably one of its molecular mechanisms.

  6. Deciphering molecular mechanism underlying hypolipidemic activity of echinocystic Acid.

    Science.gov (United States)

    Han, Li; Lai, Peng; Du, Jun-Rong

    2014-01-01

    Our previous study showed that a triterpene mixture, consisting of echinocystic acid (EA) and oleanolic acid (OA) at a ratio of 4 : 1, dose-dependently ameliorated the hyperlipidemia and atherosclerosis in rabbits fed with high fat/high cholesterol diets. This study was aimed at exploring the mechanisms underlying antihyperlipidemic effect of EA. Molecular docking simulation of EA was performed using Molegro Virtual Docker (version: 4.3.0) to investigate the potential targets related to lipid metabolism. Based on the molecular docking information, isotope labeling method or spectrophotometry was applied to examine the effect of EA on the activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, acyl-CoA:cholesterol acyltransferase (ACAT), and diacylglycerol acyltransferase (DGAT) in rat liver microsomes. Our results revealed a strong affinity of EA towards ACAT and DGAT in molecular docking analysis, while low binding affinity existed between EA and HMG-CoA reductase as well as between EA and cholesteryl ester transfer protein. Consistent with the results of molecular docking, in vitro enzyme activity assays showed that EA inhibited ACAT and DGAT, with IC50 values of 103 and 139  μ M, respectively, and exhibited no significant effect on HMG-CoA reductase activity. The present findings suggest that EA may exert hypolipidemic effect by inhibiting the activity of ACAT and DGAT. PMID:24669228

  7. Deciphering Molecular Mechanism Underlying Hypolipidemic Activity of Echinocystic Acid

    Directory of Open Access Journals (Sweden)

    Li Han

    2014-01-01

    Full Text Available Our previous study showed that a triterpene mixture, consisting of echinocystic acid (EA and oleanolic acid (OA at a ratio of 4 : 1, dose-dependently ameliorated the hyperlipidemia and atherosclerosis in rabbits fed with high fat/high cholesterol diets. This study was aimed at exploring the mechanisms underlying antihyperlipidemic effect of EA. Molecular docking simulation of EA was performed using Molegro Virtual Docker (version: 4.3.0 to investigate the potential targets related to lipid metabolism. Based on the molecular docking information, isotope labeling method or spectrophotometry was applied to examine the effect of EA on the activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase, acyl-CoA:cholesterol acyltransferase (ACAT, and diacylglycerol acyltransferase (DGAT in rat liver microsomes. Our results revealed a strong affinity of EA towards ACAT and DGAT in molecular docking analysis, while low binding affinity existed between EA and HMG-CoA reductase as well as between EA and cholesteryl ester transfer protein. Consistent with the results of molecular docking, in vitro enzyme activity assays showed that EA inhibited ACAT and DGAT, with IC50 values of 103 and 139 μM, respectively, and exhibited no significant effect on HMG-CoA reductase activity. The present findings suggest that EA may exert hypolipidemic effect by inhibiting the activity of ACAT and DGAT.

  8. Molecular subtyping of serous ovarian tumors reveals multiple connections to intrinsic breast cancer subtypes.

    Directory of Open Access Journals (Sweden)

    Jenny-Maria Jönsson

    Full Text Available OBJECTIVE: Transcriptional profiling of epithelial ovarian cancer has revealed molecular subtypes correlating to biological and clinical features. We aimed to determine gene expression differences between malignant, benign and borderline serous ovarian tumors, and investigate similarities with the well-established intrinsic molecular subtypes of breast cancer. METHODS: Global gene expression profiling using Illumina's HT12 Bead Arrays was applied to 59 fresh-frozen serous ovarian malignant, benign and borderline tumors. Nearest centroid classification was performed applying previously published gene profiles for the ovarian and breast cancer subtypes. Correlations to gene expression modules representing key biological breast cancer features were also sought. Validation was performed using an independent, publicly available dataset. RESULTS: 5,944 genes were significantly differentially expressed between benign and malignant serous ovarian tumors, with cell cycle processes enriched in the malignant subgroup. Borderline tumors were split between the two clusters. Significant correlations between the malignant serous tumors and the highly aggressive ovarian cancer signatures, and the basal-like breast cancer subtype were found. The benign and borderline serous tumors together were significantly correlated to the normal-like breast cancer subtype and the ovarian cancer signature derived from borderline tumors. The borderline tumors in the study dataset, in addition, also correlated significantly to the luminal A breast cancer subtype. These findings remained when analyzed in an independent dataset, supporting links between the molecular subtypes of ovarian cancer and breast cancer beyond those recently acknowledged. CONCLUSIONS: These data link the transcriptional profiles of serous ovarian cancer to the intrinsic molecular subtypes of breast cancer, in line with the shared clinical and molecular features between high-grade serous ovarian cancer and

  9. The lipid-reactive oxygen species phenotype of breast cancer. Raman spectroscopy and mapping, PCA and PLSDA for invasive ductal carcinoma and invasive lobular carcinoma. Molecular tumorigenic mechanisms beyond Warburg effect.

    Science.gov (United States)

    Surmacki, Jakub; Brozek-Pluska, Beata; Kordek, Radzislaw; Abramczyk, Halina

    2015-04-01

    Vibrational signatures of human breast tissue (invasive ductal carcinoma and invasive lobular carcinoma) were used to identify, characterize and discriminate structures in normal (noncancerous) and cancerous tissues by confocal Raman imaging, Raman spectroscopy and IR spectroscopy. The most important differences between normal and cancerous tissues were found in regions characteristic for vibrations of carotenoids, fatty acids, proteins, and interfacial water. Particular attention was paid to the role played by unsaturated fatty acids and their derivatives. K-means clustering and basis analysis followed by PCA and PLSDA is employed to analyze Raman spectroscopic maps of human breast tissue and for a statistical analysis of the samples (82 patients, 164 samples). Raman maps successfully identify regions of carotenoids, fatty acids, and proteins. The intensities, frequencies and profiles of the average Raman spectra differentiate the biochemical composition of normal and cancerous tissues. The paper demonstrates that Raman imaging has reached a clinically relevant level in regard to breast cancer diagnosis applications. The sensitivity and specificity obtained directly from PLSLD and cross validation are equal to 90.5% and 84.8% for calibration and 84.7% and 71.9% for cross-validation respectively.

  10. Pain in Breast Cancer Treatment: Aggravating Factors and Coping Mechanisms

    OpenAIRE

    Maria de Fatima Guerreiro Godoy; Livia Maria Pereira de Godoy; Stelamarys Barufi; José Maria Pereira de Godoy

    2014-01-01

    The objective of this study was to evaluate pain in women with breast cancer-related lymphedema and the characteristics of aggravating factors and coping mechanisms. The study was conducted in the Clinica Godoy, São Jose do Rio Preto, with a group of 46 women who had undergone surgery for the treatment of breast cancer. The following variables were evaluated: type and length of surgery; number of radiotherapy and chemotherapy sessions; continued feeling of the removed breast (phantom limb), i...

  11. Effects on DNA Damage and/or Repair Processes as Biological Mechanisms Linking Psychological Stress to Cancer Risk

    OpenAIRE

    Jenkins, Frank J; Van Houten, Bennett; Bovbjerg, Dana H

    2014-01-01

    Considerable research effort in the past several decades has focused on the impact of psychological stress, and stress hormones, on cancer progression. Numerous studies have reported that stress hormone treatment or in vivo stress exposure can enhance the growth of tumor cell lines in vitro, as well as tumors in animal models, and have begun to explore molecular mechanisms. Comparatively little research has focused on the impact of psychological stress and stress hormones on cancer initiation...

  12. Alterations in cancer cell mechanical properties after fluid shear stress exposure: a micropipette aspiration study

    Directory of Open Access Journals (Sweden)

    Chivukula VK

    2015-01-01

    Full Text Available Venkat Keshav Chivukula,1 Benjamin L Krog,1,2 Jones T Nauseef,2 Michael D Henry,2 Sarah C Vigmostad1 1Department of Biomedical Engineering, 2Department of Molecular Physiology and Biophysics, Holden Comprehensive Cancer Center, University of Iowa, Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, USA Abstract: Over 90% of cancer deaths result not from primary tumor development, but from metastatic tumors that arise after cancer cells circulate to distal sites via the circulatory system. While it is known that metastasis is an inefficient process, the effect of hemodynamic parameters such as fluid shear stress (FSS on the viability and efficacy of metastasis is not well understood. Recent work has shown that select cancer cells may be able to survive and possibly even adapt to FSS in vitro. The current research seeks to characterize the effect of FSS on the mechanical properties of suspended cancer cells in vitro. Nontransformed prostate epithelial cells (PrEC LH and transformed prostate cancer cells (PC-3 were used in this study. The Young's modulus was determined using micropipette aspiration. We examined cells in suspension but not exposed to FSS (unsheared and immediately after exposure to high (6,400 dyn/cm2 and low (510 dyn/cm2 FSS. The PrEC LH cells were ~140% stiffer than the PC-3 cells not exposed to FSS. Post-FSS exposure, there was an increase of ~77% in Young's modulus after exposure to high FSS and a ~47% increase in Young's modulus after exposure to low FSS for the PC-3 cells. There was no significant change in the Young's modulus of PrEC LH cells post-FSS exposure. Our findings indicate that cancer cells adapt to FSS, with an increased Young's modulus being one of the adaptive responses, and that this adaptation is specific only to PC-3 cells and is not seen in PrEC LH cells. Moreover, this adaptation appears to be graded in response to the magnitude of FSS experienced by the cancer cells. This is the first study

  13. Molecular Mechanisms of Cognitive Dysfunction following Traumatic Brain Injury

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    Kendall Rae Walker

    2013-07-01

    Full Text Available Traumatic brain injury (TBI results in significant disability due to cognitive deficits particularly in attention, learning and memory and higher-order executive functions. The role of TBI in chronic neurodegeneration and the development of neurodegenerative diseases including Alzheimer’s disease (AD, Parkinson’s disease (PD, Amyotrophic Lateral Sclerosis (ALS and most recently chronic traumatic encephalopathy (CTE is of particular importance. However, despite significant effort very few therapeutic options exist to prevent or reverse cognitive impairment following TBI. In this review we present experimental evidence of the known secondary injury mechanisms which contribute to neuronal cell loss, axonal injury and synaptic dysfunction and hence cognitive impairment both acutely and chronically following TBI. In particular we focus on the mechanisms linking TBI to the development of two forms of dementia: AD and CTE. We provide evidence of potential molecular mechanisms involved in modulating Aβ and Tau following TBI and provide evidence of the role of these mechanisms in AD pathology. Additionally we propose a mechanism by which Aβ generated as a direct result of TBI is capable of exacerbating secondary injury mechanisms thereby establishing a neurotoxic cascade that leads to chronic neurodegeneration.

  14. ACK1/TNK2 tyrosine kinase: molecular signaling and evolving role in cancers.

    Science.gov (United States)

    Mahajan, K; Mahajan, N P

    2015-08-01

    Deregulated tyrosine kinase signaling alters cellular homeostasis to drive cancer progression. The emergence of a non-receptor tyrosine kinase (non-RTK), ACK1 (also known as activated Cdc42-associated kinase 1 or TNK2) as an oncogenic kinase, has uncovered novel mechanisms by which tyrosine kinase signaling promotes cancer progression. Although early studies focused on ACK1 as a cytosolic effector of activated transmembrane RTKs, wherein it shuttles between the cytosol and the nucleus to rapidly transduce extracellular signals from the RTKs to the intracellular effectors, recent data unfold a new aspect of its functionality as an epigenetic regulator. ACK1 interacts with the estrogen receptor (ER)/histone demethylase KDM3A (JHDM2a) complex, which modifies KDM3A by tyrosine phosphorylation to regulate the transcriptional outcome at HOXA1 locus to promote the growth of tamoxifen-resistant breast cancer. It is also well established that ACK1 regulates the activity of androgen receptor (AR) by tyrosine phosphorylation to fuel the growth of hormone-refractory prostate cancers. Further, recent explosion in genomic sequencing has revealed recurrent ACK1 gene amplification and somatic mutations in a variety of human malignancies, providing a molecular basis for its role in neoplastic transformation. In this review, we will discuss the various facets of ACK1 signaling, including its newly uncovered epigenetic regulator function, which enables cells to bypass the blockade to major survival pathways to promote resistance to standard cancer treatments. Not surprisingly, cancer cells appear to acquire an 'addiction' to ACK1-mediated survival, particularly under stress conditions, such as growth factor deprivation or genotoxic insults or hormone deprivation. With the accelerated development of potent and selective ACK1 inhibitors, targeted treatment for cancers harboring aberrant ACK1 activity may soon become a clinical reality.

  15. The molecular mechanism and physiological role of cytoplasmic streaming.

    Science.gov (United States)

    Tominaga, Motoki; Ito, Kohji

    2015-10-01

    Cytoplasmic streaming occurs widely in plants ranging from algae to angiosperms. However, the molecular mechanism and physiological role of cytoplasmic streaming have long remained unelucidated. Recent molecular genetic approaches have identified specific myosin members (XI-2 and XI-K as major and XI-1, XI-B, and XI-I as minor motive forces) for the generation of cytoplasmic streaming among 13 myosin XIs in Arabidopsis thaliana. Simultaneous knockout of these myosin XI members led to a reduced velocity of cytoplasmic streaming and marked defects of plant development. Furthermore, the artificial modifications of myosin XI-2 velocity changed plant and cell sizes along with the velocity of cytoplasmic streaming. Therefore, we assume that cytoplasmic streaming is one of the key regulators in determining plant size.

  16. Mechanisms of Helicobacter pylori antibiotic resistance and molecular testing

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    Toshihiro eNishizawa

    2014-10-01

    Full Text Available Antibiotic resistance in Helicobacter pylori (H. pylori is the main factor affecting the efficacy of current treatment methods against infection caused by this organism. The traditional culture methods for testing bacterial susceptibility to antibiotics are expensive and require 10 to 14 days. Since resistance to clarithromycin, fluoroquinolone, and tetracycline seems to be exclusively caused by specific mutations in a small region of the responsible gene, molecular methods offer an attractive alternative to the above-mentioned techniques. The technique of polymerase chain reaction (PCR is an accurate and rapid method for the detection of mutations that confer antibiotic resistance. This review highlights the mechanisms of antibiotic resistance in H. pylori and the molecular methods for antibiotic susceptibility testing.

  17. Complement system part I - molecular mechanisms of activation and regulation

    Directory of Open Access Journals (Sweden)

    Nicolas eMerle

    2015-06-01

    Full Text Available Complement is a complex innate immune surveillance system, playing a key role in defense against pathogens and in host homeostasis. The complement system is initiated by conformational changes in recognition molecular complexes upon sensing danger signals. The subsequent cascade of enzymatic reactions is tightly regulated to assure that complement is activated only at specific locations requiring defense against pathogens, thus avoiding host tissue damage. Here we discuss the recent advances describing the molecular and structural basis of activation and regulation of the complement pathways and their implication on physiology and pathology. This article will review the mechanisms of activation of alternative, classical and lectin pathways, the formation of C3 and C5 convertases, the action of anaphylatoxins and the membrane attack complex. We will also discuss the importance of structure-function relationships using the example of atypical hemolytic uremic syndrome. Lastly we will discuss the development and benefits of therapies using complement inhibitors.

  18. Molecular Principles of Gene Fusion Mediated Rewiring of Protein Interaction Networks in Cancer.

    Science.gov (United States)

    Latysheva, Natasha S; Oates, Matt E; Maddox, Louis; Flock, Tilman; Gough, Julian; Buljan, Marija; Weatheritt, Robert J; Babu, M Madan

    2016-08-18

    Gene fusions are common cancer-causing mutations, but the molecular principles by which fusion protein products affect interaction networks and cause disease are not well understood. Here, we perform an integrative analysis of the structural, interactomic, and regulatory properties of thousands of putative fusion proteins. We demonstrate that genes that form fusions (i.e., parent genes) tend to be highly connected hub genes, whose protein products are enriched in structured and disordered interaction-mediating features. Fusion often results in the loss of these parental features and the depletion of regulatory sites such as post-translational modifications. Fusion products disproportionately connect proteins that did not previously interact in the protein interaction network. In this manner, fusion products can escape cellular regulation and constitutively rewire protein interaction networks. We suggest that the deregulation of central, interaction-prone proteins may represent a widespread mechanism by which fusion proteins alter the topology of cellular signaling pathways and promote cancer. PMID:27540857

  19. Common molecular pathways involved in human CD133+/CD34+ progenitor cell expansion and cancer

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    Vêncio Ricardo Z

    2007-06-01

    Full Text Available Abstract Background Uncovering the molecular mechanism underlying expansion of hematopoietic stem and progenitor cells is critical to extend current therapeutic applications and to understand how its deregulation relates to leukemia. The characterization of genes commonly relevant to stem/progenitor cell expansion and tumor development should facilitate the identification of novel therapeutic targets in cancer. Methods CD34+/CD133+ progenitor cells were purified from human umbilical cord blood and expanded in vitro. Correlated molecular changes were analyzed by gene expression profiling using microarrays covering up to 55,000 transcripts. Genes regulated during progenitor cell expansion were identified and functionally classified. Aberrant expression of such genes in cancer was indicated by in silico SAGE. Differential expression of selected genes was assessed by real-time PCR in hematopoietic cells from chronic myeloid leukemia patients and healthy individuals. Results Several genes and signaling pathways not previously associated with ex vivo expansion of CD133+/CD34+ cells were identified, most of which associated with cancer. Regulation of MEK/ERK and Hedgehog signaling genes in addition to numerous proto-oncogenes was detected during conditions of enhanced progenitor cell expansion. Quantitative real-time PCR analysis confirmed down-regulation of several newly described cancer-associated genes in CD133+/CD34+ cells, including DOCK4 and SPARCL1 tumor suppressors, and parallel results were verified when comparing their expression in cells from chronic myeloid leukemia patients Conclusion Our findings reveal potential molecular targets for oncogenic transformation in CD133+/CD34+ cells and strengthen the link between deregulation of stem/progenitor cell expansion and the malignant process.

  20. The molecular mechanism of HOTAIR in tumorigenesis, metastasis, and drug resistance.

    Science.gov (United States)

    Zhou, Xiaolong; Chen, Jin; Tang, Wenru

    2014-12-01

    Long non-coding RNAs have been reported to play an important role in cellular metabolism and development. Homeobox transcript antisense intergenic RNA (HOTAIR), a long non-coding RNA, is pervasively over-expressed in most human cancers compared with non-cancerous adjacent tissues. Although many articles have reported that HOTAIR is closely associated with metastasis, epithelial-mesenchymal transition, advanced pathological stage, drug resistance, and poor prognosis, the role of HOTAIR in gene regulation and tumor development is largely unknown, and the potential molecular mechanisms are not completely clear yet. In this review, we summarized the recent progress in the study of the major functions of HOTAIR. miR-331-3p, miR-130a, miR-7, miR-141, HER2, c-MYC, WIF-1, RBM38, PTEN, and Col-1 are involved in the HOTAIR regulation network. We tried to elucidate the molecular mechanisms of HOTAIR in the aspects of tumorigenesis, metastasis, drug resistance, and regulation. PMID:25385164

  1. Providing a molecular mechanism for P-glycoprotein; why would I bother?

    Science.gov (United States)

    Callaghan, Richard

    2015-10-01

    It is almost 40 years since the drug efflux pump P-glycoprotein (permeability glycoprotein or P-gp) was shown to confer multi-drug resistance in cancer cells. This protein has been one of the most extensively investigated transport proteins due to its intriguing mechanism and its affect in oncology. P-gp is known to interact with over 300 compounds and the ability to achieve this has not yet been revealed. Following the binding of substrate and nucleotide, a complex series of conformational changes in the membrane and cytosolic domains translocates substrate across the membrane. Despite over 30 years of biochemical investigation, the availability of structural data and a plethora of chemical tools to modulate its function, the molecular mechanism remains a mystery. In addition, overcoming its activity in resistant cancer cells has not been achieved in the clinic, thereby garnering some degree of pessimism in the field. This review highlights the progress that has been achieved in understanding this complex protein and the value of undertaking molecular studies.

  2. Molecular Mechanisms of Bone Metastasis: Which Targets Came from the Bench to the Bedside?

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    Sandra Casimiro

    2016-08-01

    Full Text Available Bone metastases ultimately result from a complex interaction between cancer cells and bone microenvironment. However, prior to the colonization of the bone, cancer cells must succeed through a series of steps that will allow them to detach from the primary tumor, enter into circulation, recognize and adhere to specific endothelium, and overcome dormancy. We now know that as important as the metastatic cascade, tumor cells prime the secondary organ microenvironment prior to their arrival, reflecting the existence of specific metastasis-initiating cells in the primary tumor and circulating osteotropic factors. The deep comprehension of the molecular mechanisms of bone metastases may allow the future development of specific anti-tumoral therapies, but so far the approved and effective therapies for bone metastatic disease are mostly based in bone-targeted agents, like bisphosphonates, denosumab and, for prostate cancer, radium-223. Bisphosphonates and denosumab have proven to be effective in blocking bone resorption and decreasing morbidity; furthermore, in the adjuvant setting, these agents can decrease bone relapse after breast cancer surgery in postmenopausal women. In this review, we will present and discuss some examples of applied knowledge from the bench to the bed side in the field of bone metastasis.

  3. Steered Molecular Dynamics Methods Applied to Enzyme Mechanism and Energetics.

    Science.gov (United States)

    Ramírez, C L; Martí, M A; Roitberg, A E

    2016-01-01

    One of the main goals of chemistry is to understand the underlying principles of chemical reactions, in terms of both its reaction mechanism and the thermodynamics that govern it. Using hybrid quantum mechanics/molecular mechanics (QM/MM)-based methods in combination with a biased sampling scheme, it is possible to simulate chemical reactions occurring inside complex environments such as an enzyme, or aqueous solution, and determining the corresponding free energy profile, which provides direct comparison with experimental determined kinetic and equilibrium parameters. Among the most promising biasing schemes is the multiple steered molecular dynamics method, which in combination with Jarzynski's Relationship (JR) allows obtaining the equilibrium free energy profile, from a finite set of nonequilibrium reactive trajectories by exponentially averaging the individual work profiles. However, obtaining statistically converged and accurate profiles is far from easy and may result in increased computational cost if the selected steering speed and number of trajectories are inappropriately chosen. In this small review, using the extensively studied chorismate to prephenate conversion reaction, we first present a systematic study of how key parameters such as pulling speed, number of trajectories, and reaction progress are related to the resulting work distributions and in turn the accuracy of the free energy obtained with JR. Second, and in the context of QM/MM strategies, we introduce the Hybrid Differential Relaxation Algorithm, and show how it allows obtaining more accurate free energy profiles using faster pulling speeds and smaller number of trajectories and thus smaller computational cost. PMID:27497165

  4. Molecular and Mechanical Causes of Microtubule Catastrophe and Aging.

    Science.gov (United States)

    Zakharov, Pavel; Gudimchuk, Nikita; Voevodin, Vladimir; Tikhonravov, Alexander; Ataullakhanov, Fazoil I; Grishchuk, Ekaterina L

    2015-12-15

    Tubulin polymers, microtubules, can switch abruptly from the assembly to shortening. These infrequent transitions, termed "catastrophes", affect numerous cellular processes but the underlying mechanisms are elusive. We approached this complex stochastic system using advanced coarse-grained molecular dynamics modeling of tubulin-tubulin interactions. Unlike in previous simplified models of dynamic microtubules, the catastrophes in this model arise owing to fluctuations in the composition and conformation of a growing microtubule tip, most notably in the number of protofilament curls. In our model, dynamic evolution of the stochastic microtubule tip configurations over a long timescale, known as the system's "aging", gives rise to the nonexponential distribution of microtubule lifetimes, consistent with experiment. We show that aging takes place in the absence of visible changes in the microtubule wall or tip, as this complex molecular-mechanical system evolves slowly and asymptotically toward the steady-state level of the catastrophe-promoting configurations. This new, to our knowledge, theoretical basis will assist detailed mechanistic investigations of the mechanisms of action of different microtubule-binding proteins and drugs, thereby enabling accurate control over the microtubule dynamics to treat various pathologies. PMID:26682815

  5. Molecular targets of dietary agents for prevention and therapy of cancer.

    Science.gov (United States)

    Aggarwal, Bharat B; Shishodia, Shishir

    2006-05-14

    While fruits and vegetables are recommended for prevention of cancer and other diseases, their active ingredients (at the molecular level) and their mechanisms of action less well understood. Extensive research during the last half century has identified various molecular targets that can potentially be used not only for the prevention of cancer but also for treatment. However, lack of success with targeted monotherapy resulting from bypass mechanisms has forced researchers to employ either combination therapy or agents that interfere with multiple cell-signaling pathways. In this review, we present evidence that numerous agents identified from fruits and vegetables can interfere with several cell-signaling pathways. The agents include curcumin (turmeric), resveratrol (red grapes, peanuts and berries), genistein (soybean), diallyl sulfide (allium), S-allyl cysteine (allium), allicin (garlic), lycopene (tomato), capsaicin (red chilli), diosgenin (fenugreek), 6-gingerol (ginger), ellagic acid (pomegranate), ursolic acid (apple, pears, prunes), silymarin (milk thistle), anethol (anise, camphor, and fennel), catechins (green tea), eugenol (cloves), indole-3-carbinol (cruciferous vegetables), limonene (citrus fruits), beta carotene (carrots), and dietary fiber. For instance, the cell-signaling pathways inhibited by curcumin alone include NF-kappaB, AP-1, STAT3, Akt, Bcl-2, Bcl-X(L), caspases, PARP, IKK, EGFR, HER2, JNK, MAPK, COX2, and 5-LOX. The active principle identified in fruit and vegetables and the molecular targets modulated may be the basis for how these dietary agents not only prevent but also treat cancer and other diseases. This work reaffirms what Hippocrates said 25 centuries ago, let food be thy medicine and medicine be thy food. PMID:16563357

  6. Molecular Basis of the Anti-Cancer Effects of Genistein Isoflavone in LNCaP Prostate Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Hartmann J

    2011-03-01

    Full Text Available Background: Prostate cancer is the most common form of non-skin cancer within the United States and the second leading cause of cancer deaths. Survival rates for the advanced disease remain relatively low, and conventional treatments may be accompanied by significant side effects. As a result, current research is aimed at alternative or adjuvant treatments that will target components of the signal transduction, cell-cycle and apoptosis pathways, to induce cell death with little or no toxic side effects to the patient. In this study, we investigated the effect of genistein isoflavone, a soy derivative, on expression levels of genes involved in these pathways. The mechanism of genistein-induced cell death was also investigated. The chemosensitivity of the LNCaP prostate cancer cells to genistein was investigated using ATP and MTS assays, and a caspase binding assay was used to determine apoptosis induction. Several molecular targets were determined using cDNA microarray and RT-PCR analysis.Results: The overall data revealed that genistein induces cell death in a time- and dose-dependent manner, and regulates expression levels of several genes involved in carcinogenesis and immunity. Several cell-cycle genes were down-regulated, including the mitotic kinesins, cyclins and cyclin-dependent kinases. Various members of the Bcl-2 family of apoptotic proteins were also affected. The DefB1 and the HLA membrane receptor genes involved in immunogenicity were also up-regulated.Conclusion: The results indicate that genistein inhibits growth of the hormone-dependent prostate cancer cells, LNCaP, via apoptosis induction through regulation of some of the genes involved in carcinogenesis of many tumors, and immunogenicity. This study augments the potential phytotherapeutic and immunotherapeutic significance of genistein isoflavone.

  7. United polarizable multipole water model for molecular mechanics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Rui; Wang, Qiantao; Ren, Pengyu, E-mail: pren@mail.utexas.edu [Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712 (United States); Wang, Lee-Ping; Pande, Vijay S. [Department of Chemistry, Stanford University, Stanford, California 94305 (United States)

    2015-07-07

    We report the development of a united AMOEBA (uAMOEBA) polarizable water model, which is computationally 3–5 times more efficient than the three-site AMOEBA03 model in molecular dynamics simulations while providing comparable accuracy for gas-phase and liquid properties. In this coarse-grained polarizable water model, both electrostatic (permanent and induced) and van der Waals representations have been reduced to a single site located at the oxygen atom. The permanent charge distribution is described via the molecular dipole and quadrupole moments and the many-body polarization via an isotropic molecular polarizability, all located at the oxygen center. Similarly, a single van der Waals interaction site is used for each water molecule. Hydrogen atoms are retained only for the purpose of defining local frames for the molecular multipole moments and intramolecular vibrational modes. The parameters have been derived based on a combination of ab initio quantum mechanical and experimental data set containing gas-phase cluster structures and energies, and liquid thermodynamic properties. For validation, additional properties including dimer interaction energy, liquid structures, self-diffusion coefficient, and shear viscosity have been evaluated. The results demonstrate good transferability from the gas to the liquid phase over a wide range of temperatures, and from nonpolar to polar environments, due to the presence of molecular polarizability. The water coordination, hydrogen-bonding structure, and dynamic properties given by uAMOEBA are similar to those derived from the all-atom AMOEBA03 model and experiments. Thus, the current model is an accurate and efficient alternative for modeling water.

  8. Molecular mechanisms in autoimmune type 1 diabetes: a critical review.

    Science.gov (United States)

    Xie, Zhiguo; Chang, Christopher; Zhou, Zhiguang

    2014-10-01

    Autoimmune type 1 diabetes is characterized by selective destruction of insulin-secreting beta cells in the pancreas of genetically susceptible individuals. The mechanisms underlying the development of type 1 diabetes are not fully understood. However, a widely accepted point is that type 1 diabetes is caused by a combination of genetic and environmental factors. Although most type 1 diabetes patients do not have a family history, genetic susceptibility does play a vital role in beta cell autoimmunity and destruction. Human leukocyte antigen (HLA) regions are the strongest genetic determinants, which can contribute 40-50 % of the genetic risk to type 1 diabetes. Other genes, including INS also contribute to disease risk. The mechanisms of the susceptible genes in type 1 diabetes may relate to their respective roles in antigen presentation, beta cell autoimmunity, immune tolerance, and autoreactive T cell response. Environmental susceptibility factors also contribute to the risk of developing type 1 diabetes. From an epigenetic standpoint, the pathologic mechanisms involved in the development of type 1 diabetes may include DNA methylation, histone modification, microRNA, and molecular mimicry. These mechanisms may act through regulating of gene expression, thereby affecting the immune system response toward islet beta cells. One of the characteristics of type 1 diabetes is the recognition of islet autoantigens by autoreactive CD4(+) and CD8(+) T cells and autoantibodies. Autoantibodies against islet autoantigens are involved in autoantigen processing and presentation by HLA molecules. This review will mainly focus on the molecular mechanism by which genetic, epigenetic, and environmental factors contribute to the risk of type 1 diabetes. PMID:24752371

  9. Molecular mechanisms in autoimmune type 1 diabetes: a critical review.

    Science.gov (United States)

    Xie, Zhiguo; Chang, Christopher; Zhou, Zhiguang

    2014-10-01

    Autoimmune type 1 diabetes is characterized by selective destruction of insulin-secreting beta cells in the pancreas of genetically susceptible individuals. The mechanisms underlying the development of type 1 diabetes are not fully understood. However, a widely accepted point is that type 1 diabetes is caused by a combination of genetic and environmental factors. Although most type 1 diabetes patients do not have a family history, genetic susceptibility does play a vital role in beta cell autoimmunity and destruction. Human leukocyte antigen (HLA) regions are the strongest genetic determinants, which can contribute 40-50 % of the genetic risk to type 1 diabetes. Other genes, including INS also contribute to disease risk. The mechanisms of the susceptible genes in type 1 diabetes may relate to their respective roles in antigen presentation, beta cell autoimmunity, immune tolerance, and autoreactive T cell response. Environmental susceptibility factors also contribute to the risk of developing type 1 diabetes. From an epigenetic standpoint, the pathologic mechanisms involved in the development of type 1 diabetes may include DNA methylation, histone modification, microRNA, and molecular mimicry. These mechanisms may act through regulating of gene expression, thereby affecting the immune system response toward islet beta cells. One of the characteristics of type 1 diabetes is the recognition of islet autoantigens by autoreactive CD4(+) and CD8(+) T cells and autoantibodies. Autoantibodies against islet autoantigens are involved in autoantigen processing and presentation by HLA molecules. This review will mainly focus on the molecular mechanism by which genetic, epigenetic, and environmental factors contribute to the risk of type 1 diabetes.

  10. Investigation of molecular mechanisms and regulatory pathways of pro-angiogenic nanorods

    Science.gov (United States)

    Nethi, Susheel Kumar; Veeriah, Vimal; Barui, Ayan Kumar; Rajendran, Saranya; Mattapally, Saidulu; Misra, Sanjay; Chatterjee, Suvro; Patra, Chitta Ranjan

    2015-05-01

    Angiogenesis, a process involving the growth of new blood vessels from the pre-existing vasculature, plays a crucial role in various pathophysiological conditions. We have previously demonstrated that europium hydroxide [EuIII(OH)3] nanorods (EHNs) exhibit pro-angiogenic properties through the generation of reactive oxygen species (ROS) and mitogen activated protein kinase (MAPK) activation. Considering the enormous implication of angiogenesis in cardiovascular diseases (CVDs) and cancer, it is essential to understand in-depth molecular mechanisms and signaling pathways in order to develop the most efficient and effective alternative treatment strategy for CVDs. However, the exact underlying mechanism and cascade signaling pathways behind the pro-angiogenic properties exhibited by EHNs still remain unclear. Herein, we report for the first time that the hydrogen peroxide (H2O2), a redox signaling molecule, generated by these EHNs activates the endothelial nitric oxide synthase (eNOS) that promotes the nitric oxide (NO) production in a PI3K (phosphoinositide 3-kinase)/Akt dependent manner, eventually triggering angiogenesis. We intensely believe that the investigation and understanding of the in-depth molecular mechanism and signaling pathways of EHNs induced angiogenesis will help us in developing an effective alternative treatment strategy for cardiovascular related and ischemic diseases where angiogenesis plays an important role.Angiogenesis, a process involving the growth of new blood vessels from the pre-existing vasculature, plays a crucial role in various pathophysiological conditions. We have previously demonstrated that europium hydroxide [EuIII(OH)3] nanorods (EHNs) exhibit pro-angiogenic properties through the generation of reactive oxygen species (ROS) and mitogen activated protein kinase (MAPK) activation. Considering the enormous implication of angiogenesis in cardiovascular diseases (CVDs) and cancer, it is essential to understand in-depth molecular

  11. Book Review of "The Molecular Biology of Cancer" by Stella Pelengaris, Michael Khan (Editors

    Directory of Open Access Journals (Sweden)

    Schmidt Christian

    2007-11-01

    Full Text Available Abstract Here, a review of "The Molecular Biology of Cancer" (Stella Pelengaris and Michael Khan [Editors] is given. The detailed description of the book is provided here: Pelengaris S, Khan M (Eds: The Molecular Biology of Cancer; Blackwell Publishing, Oxford (U.K.; 2006. 531 pages, 214 illustrations, ISBN 9-78140-511-814-9, £31.99.

  12. Mechanical Properties of Gelatin Gels; Effect of Molecular Weight and Molecular Weight Distribution

    OpenAIRE

    Jonhard, Eysturskarð

    2010-01-01

    The goal of the gelatin manufacturer is to partial hydrolyze the covalent cross-linkages that organize the collagen molecules into a quarter staggered arrangement found in connective tissue, to minimize the hydrolysis of the peptide bonds and to obtain the appropriate molecular weigh distribution (MWD) for a specific application.The mechanical properties of the resulting gelatin are known to be influenced by the tissues and species from which it is produced as well as the pretreatment and ext...

  13. Molecular Mechanism of Allosteric Communication in Hsp70 Revealed by Molecular Dynamics Simulations

    OpenAIRE

    Chiappori, Federica; Merelli, Ivan; Colombo, Giorgio; Milanesi, Luciano; Morra, Giulia

    2012-01-01

    Author Summary Allostery, or the capability of proteins to respond to ligand binding events with a variation in structure or dynamics at a distant site, is a common feature for biomolecular function and regulation in a large number of proteins. Intra-protein connections and inter-residue coordinations underlie allosteric mechanisms and react to binding primarily through a finely tuned modulation of motions and structures at the microscopic scale. Hence, all-atom molecular dynamics simulations...

  14. Molecular and Electrophysiological Mechanisms Underlying Cardiac Arrhythmogenesis in Diabetes Mellitus.

    Science.gov (United States)

    Tse, Gary; Lai, Eric Tsz Him; Tse, Vivian; Yeo, Jie Ming

    2016-01-01

    Diabetes is a common endocrine disorder with an ever increasing prevalence globally, placing significant burdens on our healthcare systems. It is associated with significant cardiovascular morbidities. One of the mechanisms by which it causes death is increasing the risk of cardiac arrhythmias. The aim of this article is to review the cardiac (ion channel abnormalities, electrophysiological and structural remodelling) and extracardiac factors (neural pathway remodelling) responsible for cardiac arrhythmogenesis in diabetes. It is concluded by an outline of molecular targets for future antiarrhythmic therapy for the diabetic population. PMID:27642609

  15. Molecular mechanisms of methicillin resistance in Staphylococcus aureus.

    Science.gov (United States)

    Domínguez, M A; Liñares, J; Martín, R

    1997-09-01

    Methicillin-resistant Staphylococcus aureus (MRSA) strains are among the most common nosocomial pathogens. The most significant mechanism of resistance to methicillin in this-species is the acquisition of a genetic determinant (mecA gene). However, resistance seems to have a more complex molecular basis, since additional chromosomal material is involved in such resistance. Besides, overproduction of penicillinase and/or alterations in the PBPs can contribute to the formation of resistance phenotypes. Genetic and environmental factors leading to MRSA are reviewed.

  16. The mechanism of selective molecular capture in carbon nanotube networks.

    Science.gov (United States)

    Wan, Yu; Guan, Jun; Yang, Xudong; Zheng, Quanshui; Xu, Zhiping

    2014-07-28

    Recently, air pollution issues have drawn significant attention to the development of efficient air filters, and one of the most promising materials for this purpose is nanofibers. We explore here the mechanism of selective molecular capture of volatile organic compounds in carbon nanotube networks by performing atomistic simulations. The results are discussed with respect to the two key parameters that define the performance of nanofiltration, i.e. the capture efficiency and flow resistance, which demonstrate the advantages of carbon nanotube networks with high surface-to-volume ratio and atomistically smooth surfaces. We also reveal the important roles of interfacial adhesion and diffusion that govern selective gas transport through the network.

  17. Mechanisms linking dietary fiber, gut microbiota and colon cancer prevention.

    Science.gov (United States)

    Zeng, Huawei; Lazarova, Darina L; Bordonaro, Michael

    2014-02-15

    Many epidemiological and experimental studies have suggested that dietary fiber plays an important role in colon cancer prevention. These findings may relate to the ability of fiber to reduce the contact time of carcinogens within the intestinal lumen and to promote healthy gut microbiota, which modifies the host's metabolism in various ways. Elucidation of the mechanisms by which dietary fiber-dependent changes in gut microbiota enhance bile acid deconjugation, produce short chain fatty acids, and modulate inflammatory bioactive substances can lead to a better understanding of the beneficial role of dietary fiber. This article reviews the current knowledge concerning the mechanisms via which dietary fiber protects against colon cancer.

  18. Molecular and biochemical mechanisms of drug resistance in fungi.

    Science.gov (United States)

    Yamaguchi, H

    1999-01-01

    This paper reviews the current status of our understanding of resistance mechanisms of three major classes of antifungal drugs for systemic use, amphotericin B (AMPH), flucytosine (5-FC) and several azole antifungals, in particular fluconazole (FLCZ), at the molecular and cellular levels. Although the number of reports of AMPH- or 5-FC-resistant fungal species and strains is limited, several mechanisms of resistance have been described. AMPH-resistant Candida have a marked decrease in ergosterol content compared with AMPH-susceptible control isolates. A lesion in the UMP-pyrophosphorylase is the most frequent determinant of 5-FC resistance in C. albicans. Recently resistance of C. albicans to azoles has become an increasing problem. Extensive biochemical studies have highlighted a significant diversity in mechanisms conferring resistance to FLCZ and other azoles, which include alterations in sterol biosynthesis, target site, uptake and efflux. Among them, the most important mechanism clinically is reduced access of the drug to the intracellular P450 14 DM target, probably because of the action of a multidrug resistance efflux pump, and overproduction of that target. However, other possible resistance mechanisms for azoles remain to be identified.

  19. Molecular View of Protein Crystal Growth: Molecular Interactions, Surface Reconstruction and Growth Mechanism

    Science.gov (United States)

    Nadarajah, Arunan; Li, Huayu; Konnert, John H.; Pusey, Marc L.

    2000-01-01

    Studies of the growth and molecular packing of tetragonal lysozyme crystals suggest that there is an underlying molecular growth mechanism, in addition to the classical one involving screw dislocation/2D) nucleation growth. These crystals are constructed by strongly bonded molecular chains forming helices about the 43 axes. The helices are connected to each other by weaker bonds. Crystal growth proceeds by the formation of these 4(sub 3) helices, which would explain some unexpected observations by earlier investigators, such as bimolecular growth steps on the (110) face. Another consequence of these molecular considerations is that only one of two possible packing arrangements could occur on the crystal faces and that their growth unit was at least a tetramer corresponding to the 4(sub 3) helix. Two new high resolution atomic force microscopy (AFM) techniques were developed to directly confirm these predictions on tetragonal lysozyme crystals. Most earlier investigations of protein crystal growth with AFM were in the low resolution mode which is adequate to investigate the classical growth mechanisms, but cannot resolve molecular features and mechanisms. Employing the first of the newly developed techniques, high resolution AFM images of the (110) face were compared with the theoretically constructed images for the two possible packing arrangements on this face. The prediction that the molecular packing arrangement of these faces corresponded to that for complete 4(sub 3) helices was confirmed in this manner. This investigation also showed the occurrence of surface reconstruction on protein crystals. The molecules on the surface of the (110) face were found to pack closer along the 4(sub 3) axes than those in the interior. The second new AFM technique was used to follow the growth process by measuring the dimensions of individual growth units on the (110) face. Linescans across a growth step, performed near the saturation limit of the crystals, allowed the growth

  20. Clinical and Molecular Characteristics of Post-Colonoscopy Colorectal Cancer

    DEFF Research Database (Denmark)

    Stoffel, Elena M; Erichsen, Rune; Frøslev, Trine;

    2016-01-01

    BACKGROUND AND AIMS: Colonoscopy provides incomplete protection from colorectal cancer (CRC), but determinants of post-colonoscopy CRC are not well understood. We compared clinical features and molecular characteristics of CRCs diagnosed at different time intervals after a previous colonoscopy....... METHODS: We performed a population-based, cross-sectional study of incident CRC cases in Denmark (2007-2011), categorized as post-colonoscopy or detected during diagnostic colonoscopy (in patients with no prior colonoscopy). We compared prevalence of proximal location and DNA mismatch repair deficiency (d......MMR) in CRC tumors, relative to time since previous colonoscopy, using logistic regression and cubic splines to assess temporal variation. RESULTS: Of 10,365 incident CRCs, 725 occurred after colonoscopy examinations (7.0%). These were more often located in the proximal colon (odds ratio [OR], 2.34; 95% CI, 1...

  1. Molecular and Computational Studies on Apoptotic Pathway Regulator, Bcl-2 Gene from Breast Cancer Cell Line MCF-7.

    Science.gov (United States)

    Tiwari, Pragya; Khan, M J

    2016-01-01

    Cancer is a dreadful disease constituting abnormal growth and proliferation of malignant cells in the body. Next to lung cancer, breast cancer is the most common form of cancer affecting women. The apoptotic pathway regulators, B cell lymphoma family of protein, play a key role in various malignancies defining cancer and their constitutive expression plays an integral role in breast cancer chemotherapy. The research work discusses the identification and molecular cloning of a B cell lymphoma like gene from human breast cancer cell line. The open reading frame of the gene consisted of 965 nucleotides, encoding a protein of 380 amino acids with a predicted molecular weight of 42.5 kilodalton. The predicted physiochemical properties of the gene were as follows: Isoelectric point - 9.49, molecular formula - C1893H3004N534O548S16, total number of negatively charged residues, (Aspartate+Glutamate) - 26, total number of positively charged residues, (Arginine+Lysine)-39, instability index-42.08 (unstable protein) and grand average of hydropathicity is -0.202. Additionally, phobius prediction suggested non-cytoplasmic localization of the putative protein. The presence of secondary structure in the protein was determined by Memsat program. A 3 dimensional protein homology model was generated using threading based method of protein modeling for structural and functional annotation of the putative protein. Future prospects accounts for the biochemical characterization of the enzyme including in vitro assays on breast cancer cell line would establish the functional characteristics of the protein and its physiological mechanisms in breast cancer development and its therapeutic-target role in future. PMID:27168686

  2. Estimation of mechanical properties of single wall carbon nanotubes using molecular mechanics approach

    Indian Academy of Sciences (India)

    P Subba Rao; Sunil Anandatheertha; G Narayana Naik; G Gopalakrishnan

    2015-06-01

    Molecular mechanics based finite element analysis is adopted in the current work to evaluate the mechanical properties of Zigzag, Armchair and Chiral Single wall Carbon Nanotubes (SWCNT) of different diameters and chiralities. Three different types of atomic bonds, that is Carbon–Carbon covalent bond and two types of Carbon–Carbon van der Waals bonds are considered in the carbon nanotube system. The stiffness values of these bonds are calculated using the molecular potentials, namely Morse potential function and Lennard-Jones interaction potential function respectively and these stiffness’s are assigned to spring elements in the finite element model of the CNT. The geometry of CNT is built using a macro that is developed for the finite element analysis software. The finite element model of the CNT is constructed, appropriate boundary conditions are applied and the behavior of mechanical properties of CNT is studied.

  3. Molecular application of spectral photoacoustic imaging in pancreatic cancer pathology

    Science.gov (United States)

    Lakshman, Minalini; Hupple, Clinton; Lohse, Ines; Hedley, David; Needles, Andrew; Theodoropoulos, Catherine

    2012-12-01

    Spectral imaging is an advanced photo-acoustic (PA) mode that can discern optical absorption of contrast agent(s) in the tissue micro-environment. This advancement is made possible by precise control of optical wavelength using a tunable pulsed laser, ranging from 680-970 nm. Differential optical absorption of blood oxygenation states makes spectral imaging of hemoglobin ideal to investigate remodeling of the tumor microenvironment- a molecular change that renders resistance to standard cancer treatment. Approach: Photo-acoustic imaging was performed on the Vevo® LAZR system (VisualSonics) at 5-20 Hz. Deep abdominal imaging was accomplished with a LZ250D probe at a center frequency of 21MHz and an axial resolution of 75 μm. The tumor model was generated in an immune compromised mouse by surgical implantation of primary patient derived tumors, in the pancreas. Results: Spectral imaging for oxygen saturation at 750 nm and 850 nm characterized this tumor with a poorly oxygenated core surrounded by a well oxygenated periphery. Multispectral imaging identified a sub region in the core with a four-fold signal exclusively at 750 and 800 nm. A co-registered 2D image of this region was shown to be echogenic and calcification was suspected. Perfusion imaging with contrast enhanced ultrasound using microbubbles (Vevo MicroMarker® contrast agents, VisualSonics) identified functional vessels towards this sub region. Histology confirmed calcification and vascularization in the tumor core. Taken together, non-invasive characterization of the tumor microenvironment using photo-acoustics rendered spectral imaging a sensitive tool to monitor molecular changes representative of progression of pancreatic cancer that kills within 6 months of diagnosis.

  4. Molecular advances to treat cancer of the brain.

    Science.gov (United States)

    Fathallah-Shaykh, H M; Zhao, L J; Mickey, B; Kafrouni, A I

    2000-06-01

    Malignant primary and metastatic brain tumours continue to be associated with poor prognosis. Nevertheless, recent advances in molecular medicine, specifically in the strategies of gene therapy, targeting tumour cells, anti-angiogenesis and immunotherapy, have created novel tools that may be of therapeutic value. To date, gene therapy trials have not yet demonstrated clinical efficacy because of inherent defects in vector design. Despite this, advances in adenoviral technology, namely the helper-dependent adenoviral constructs (gutless) and the uncovering of brain parenchymal cells as effective and necessary targets for antitumour benefits of adenoviral-mediated gene transfer, suggest that developments in vector design may be approaching the point of clinical utility. Targeting tumour cells refers to strategies that destroy malignant but spare normal cells. A new assortment of oncolytic viruses have emerged, capable of specific lysis of cancer tissue while sparing normal cells and propagating until they reach the tumour borders. Furthermore, peptides have been transformed into bullets that specifically seek and destroy cancer cells. The concept of tumour angiogenesis has been challenged by new but still very controversial findings that tumour cells themselves may form blood channels. These results may lead to the redirecting of the molecular targets toward anti-angiogenesis in some tumours including glioblastoma multiform. Unfortunately, our knowledge regarding the immunological ignorance of the tumour is still limited. Even so, newly discovered molecules have shed light on novel pathways leading to the escape of the tumour from the immune system. Finally, significant limitations in our current experimental tumour models may soon be overcome by firstly, the development of models of reproducible organ-specific tumours in non-inbred animals and secondly applying genomics to individualize therapy for a particular tumour in a specific patient.

  5. Molecular markers in breast cancer: new tools in imaging and prognosis

    NARCIS (Netherlands)

    Vermeulen, J.F.

    2012-01-01

    Breast cancer is the most frequently diagnosed cancer in women. Although breast cancer is mainly diagnosed by mammography, other imaging modalities (e.g. MRI, PET) are increasingly used. The most recent developments in the field of molecular imaging comprise the application of near-infrared fluoresc

  6. Molecular Mechanisms of Two-Component Signal Transduction.

    Science.gov (United States)

    Zschiedrich, Christopher P; Keidel, Victoria; Szurmant, Hendrik

    2016-09-25

    Two-component systems (TCS) comprising sensor histidine kinases and response regulator proteins are among the most important players in bacterial and archaeal signal transduction and also occur in reduced numbers in some eukaryotic organisms. Given their importance to cellular survival, virulence, and cellular development, these systems are among the most scrutinized bacterial proteins. In the recent years, a flurry of bioinformatics, genetic, biochemical, and structural studies have provided detailed insights into many molecular mechanisms that underlie the detection of signals and the generation of the appropriate response by TCS. Importantly, it has become clear that there is significant diversity in the mechanisms employed by individual systems. This review discusses the current knowledge on common themes and divergences from the paradigm of TCS signaling. An emphasis is on the information gained by a flurry of recent structural and bioinformatics studies.

  7. RNA processing-associated molecular mechanisms of neurodegenerative diseases.

    Science.gov (United States)

    Tang, Anna Y

    2016-08-01

    Dysfunctions of RNA processing and mutations of RNA binding proteins (RBPs) play a fundamental role in the pathogenesis of many neurodegenerative diseases. To elucidate the function of RNA processing and RBPs mutations in neuronal cells and to increase our understanding on the pathogenic mechanisms of neurodegeneration, I have reviewed recent advances on RNA processing-associated molecular mechanisms of neurodegenerative diseases, including RBPs-mediated dysfunction of RNA processing, dysfunctional microRNA (miRNA)-based regulation of gene expression, and oxidative RNA modification. I have focused on neurodegeneration induced by RBPs mutations, by dysfunction of miRNA regulation, and by the oxidized RNAs within neurons, and discuss how these dysfunctions have pathologically contributed to neurodegenerative diseases. The advances overviewed above will be valuable to basic investigation and clinical application of target diagnostic tests and therapies.

  8. Molecular mechanisms for synchronous, asynchronous, and spontaneous neurotransmitter release.

    Science.gov (United States)

    Kaeser, Pascal S; Regehr, Wade G

    2014-01-01

    Most neuronal communication relies upon the synchronous release of neurotransmitters, which occurs through synaptic vesicle exocytosis triggered by action potential invasion of a presynaptic bouton. However, neurotransmitters are also released asynchronously with a longer, variable delay following an action potential or spontaneously in the absence of action potentials. A compelling body of research has identified roles and mechanisms for synchronous release, but asynchronous release and spontaneous release are less well understood. In this review, we analyze how the mechanisms of the three release modes overlap and what molecular pathways underlie asynchronous and spontaneous release. We conclude that the modes of release have key fusion processes in common but may differ in the source of and necessity for Ca(2+) to trigger release and in the identity of the Ca(2+) sensor for release. PMID:24274737

  9. Molecular Mechanisms of Survival Strategies in Extreme Conditions

    Directory of Open Access Journals (Sweden)

    Federica Migliardo

    2012-12-01

    Full Text Available Today, one of the major challenges in biophysics is to disclose the molecular mechanisms underlying biological processes. In such a frame, the understanding of the survival strategies in extreme conditions received a lot of attention both from the scientific and applicative points of view. Since nature provides precious suggestions to be applied for improving the quality of life, extremophiles are considered as useful model-systems. The main goal of this review is to present an overview of some systems, with a particular emphasis on trehalose playing a key role in several extremophile organisms. The attention is focused on the relation among the structural and dynamic properties of biomolecules and bioprotective mechanisms, as investigated by complementary spectroscopic techniques at low- and high-temperature values.

  10. Molecular mechanisms underlying the effects of statins in the central nervous system.

    Science.gov (United States)

    McFarland, Amelia J; Anoopkumar-Dukie, Shailendra; Arora, Devinder S; Grant, Gary D; McDermott, Catherine M; Perkins, Anthony V; Davey, Andrew K

    2014-11-10

    3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, commonly referred to as statins, are widely used in the treatment of dyslipidaemia, in addition to providing primary and secondary prevention against cardiovascular disease and stroke. Statins' effects on the central nervous system (CNS), particularly on cognition and neurological disorders such as stroke and multiple sclerosis, have received increasing attention in recent years, both within the scientific community and in the media. Current understanding of statins' effects is limited by a lack of mechanism-based studies, as well as the assumption that all statins have the same pharmacological effect in the central nervous system. This review aims to provide an updated discussion on the molecular mechanisms contributing to statins' possible effects on cognitive function, neurodegenerative disease, and various neurological disorders such as stroke, epilepsy, depression and CNS cancers. Additionally, the pharmacokinetic differences between statins and how these may result in statin-specific neurological effects are also discussed.

  11. Synthesis and evaluation of a peptide targeted small molecular Gd-DOTA monoamide conjugate for MR molecular imaging of prostate cancer

    OpenAIRE

    Wu, Xueming; Burden-Gulley, Susan M.; Yu, Guan-Ping; Tan, Mingqian; Lindner, Daniel; Brady-Kalnay, Susann M.; Lu, Zheng-Rong

    2012-01-01

    Tumor extracellular matrix has an abundance of cancer related proteins that can be used as biomarkers for cancer molecular imaging. Innovative design and development of safe and effective targeted contrast agents to these biomarkers would allow effective MR cancer molecular imaging with high spatial resolution. In this study, we synthesized a low molecular weight CLT1 peptide targeted Gd(III) chelate CLT1-dL-(Gd-DOTA)4 specific to clotted plasma proteins in tumor stroma for cancer MR molecula...

  12. A molecular understanding of the dynamic mechanism of aquaporin osmosis

    CERN Document Server

    Shua, Liangsuo; Qian, Xin; Wanga, Xiyun; Lin, Yixin; Tan, Kai; Shu, Chaohui; Jin, Shiping

    2014-01-01

    AQPs (aquaporins), the rapid water channels of cells, play a key role in maintaining osmotic equilibrium of cells. In this paper, we reported the dynamic mechanism of AQP osmosis at the molecular level. A theoretical model based on molecular dynamics was carried out and verified by the published experimental data. The reflection coefficients ({\\sigma}) of neutral molecules are mainly decided by their relative size with AQPs, and increase with a third power up to a constant value 1. This model also indicated that the reflection coefficient of a complete impermeable solute can be smaller than 1. The H+ concentration of solution can influence the driving force of the AQPs by changing the equivalent diameters of vestibules surrounded by loops with abundant polar amino acids. In this way, pH of solution can regulate water permeability of AQPs. Therefore, an AQP may not only work as a switch to open or close, but as a rapid response molecular valve to control its water flow. The vestibules can prevent the channel b...

  13. Mechanisms of autophagy and apoptosis:Recent developments in breast cancer cells

    Institute of Scientific and Technical Information of China (English)

    Juan; M; Esteve; Erwin; Knecht

    2011-01-01

    Autophagy,the pathway whereby cell components are degraded by lysosomes,is involved in the cell response to environmental stresses,such as nutrient deprivation,hypoxia or exposition to chemotherapeutic agents.Under these conditions,which are reminiscent of certain phases of tumor development,autophagy either promotes cell survival or induces cell death. This strengthens the possibility that autophagy could be an important target in cancer therapy,as has been proposed.Here,we describe the regulation of survival and death by autophagy and apoptosis,especially in cultured breast cancer cells.In particular,we discuss whether autophagy represents an apoptosis-independent process and/or if they share common pathways. We believe that understanding in detail the molecular mechanisms that underlie the relationships between autophagy and apoptosis in breast cancer cells could improve the available treatments for this disease.

  14. Pancreatic Cancer Gene Therapy: From Molecular Targets to Delivery Systems

    Directory of Open Access Journals (Sweden)

    Maria Victoria Maliandi

    2011-01-01

    Full Text Available The continuous identification of molecular changes deregulating critical pathways in pancreatic tumor cells provides us with a large number of novel candidates to engineer gene-targeted approaches for pancreatic cancer treatment. Targets—both protein coding and non-coding—are being exploited in gene therapy to influence the deregulated pathways to facilitate cytotoxicity, enhance the immune response or sensitize to current treatments. Delivery vehicles based on viral or non-viral systems as well as cellular vectors with tumor homing characteristics are a critical part of the design of gene therapy strategies. The different behavior of tumoral versus non-tumoral cells inspires vector engineering with the generation of tumor selective products that can prevent potential toxic-associated effects. In the current review, a detailed analysis of the different targets, the delivery vectors, the preclinical approaches and a descriptive update on the conducted clinical trials are presented. Moreover, future possibilities in pancreatic cancer treatment by gene therapy strategies are discussed.

  15. Cellular, Molecular Consequences of Peroxisome Proliferator- Activated Receptor-δ Activation in Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Sara Vignati

    2006-10-01

    Full Text Available Peroxisome proliferator-activated receptor-δ (PPAR-δ is a ligand-activated transcription factor. In addition to its canonical role in lipid, glucose metabolism, PPAR-δ controls cell proliferation, death, differentiation in several tissues. Here we have examined the expression of PPAR-δ in ovarian tumors, the cellular, molecular consequences of its activation in ovarian cancer cells. PPAR-δ was expressed in a large number of epithelial ovarian tumors, cell lines. The PPAR-δ lig, ciglitazone inhibited the growth, clonogenic survival of ovarian cancer cells, inducing cell cycle arrest, cell death. Growth inhibition by ciglitazone was reversed by the PPAR-δ antagonist GW9662, indicating the involvement of PPAR-δ- dependent mechanisms. Microarray-based gene profiling revealed complex changes in the transcriptional program of ovarian cancer cells on treatment with ciglitazone, identified multiple pathways that may contribute to PPAR-δ ligands' antitumor activity. Genes upregulated by ciglitazone were predominantly associated with metabolic, differentiation, tumorsuppressor pathways, whereas downregulated genes were involved in cell proliferation, cell cycle, cell organization, steroid biosynthesis. Collectively, our data indicate that PPAR-δ activation by selective agonists is a valid strategy for ovarian cancer therapy, prevention, should be tested alone, in combination with other anticancer drugs.

  16. Molecular Mechanisms of Phosphorus Metabolism and Transport during Leaf Senescence

    Directory of Open Access Journals (Sweden)

    Kyla A. Stigter

    2015-12-01

    Full Text Available Leaf senescence, being the final developmental stage of the leaf, signifies the transition from a mature, photosynthetically active organ to the attenuation of said function and eventual death of the leaf. During senescence, essential nutrients sequestered in the leaf, such as phosphorus (P, are mobilized and transported to sink tissues, particularly expanding leaves and developing seeds. Phosphorus recycling is crucial, as it helps to ensure that previously acquired P is not lost to the environment, particularly under the naturally occurring condition where most unfertilized soils contain low levels of soluble orthophosphate (Pi, the only form of P that roots can directly assimilate from the soil. Piecing together the molecular mechanisms that underpin the highly variable efficiencies of P remobilization from senescing leaves by different plant species may be critical for devising effective strategies for improving overall crop P-use efficiency. Maximizing Pi remobilization from senescing leaves using selective breeding and/or biotechnological strategies will help to generate P-efficient crops that would minimize the use of unsustainable and polluting Pi-containing fertilizers in agriculture. This review focuses on the molecular mechanisms whereby P is remobilized from senescing leaves and transported to sink tissues, which encompasses the action of hormones, transcription factors, Pi-scavenging enzymes, and Pi transporters.

  17. Molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis clinical isolates

    Directory of Open Access Journals (Sweden)

    Meng Dong-Ya

    2014-01-01

    Full Text Available To evaluate the molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis (MH clinical strains isolated from urogenital specimens. 15 MH clinical isolates with different phenotypes of resistance to fluoroquinolones antibiotics were screened for mutations in the quinolone resistance-determining regions (QRDRs of DNA gyrase (gyrA and gyrB and topoisomerase IV (parC and parE in comparison with the reference strain PG21, which is susceptible to fluoroquinolones antibiotics. 15 MH isolates with three kinds of quinolone resistance phenotypes were obtained. Thirteen out of these quinolone-resistant isolates were found to carry nucleotide substitutions in either gyrA or parC. There were no alterations in gyrB and no mutations were found in the isolates with a phenotype of resistance to Ofloxacin (OFX, intermediate resistant to Levofloxacin (LVX and Sparfloxacin (SFX, and those susceptible to all three tested antibiotics. The molecular mechanism of fluoroquinolone resistance in clinical isolates of MH was reported in this study. The single amino acid mutation in ParC of MH may relate to the resistance to OFX and LVX and the high-level resistance to fluoroquinolones for MH is likely associated with mutations in both DNA gyrase and the ParC subunit of topoisomerase IV.

  18. Obstructive renal injury: from fluid mechanics to molecular cell biology

    Directory of Open Access Journals (Sweden)

    Alvaro C Ucero

    2010-04-01

    Full Text Available Alvaro C Ucero1,*, Sara Gonçalves2,*, Alberto Benito-Martin1, Beatriz Santamaría1, Adrian M Ramos1, Sergio Berzal1, Marta Ruiz-Ortega1, Jesus Egido1, Alberto Ortiz11Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Fundación Renal Iñigo Alvarez de Toledo, Madrid, Spain; 2Nefrologia e Transplantação Renal, Hospital de Santa Maria EPE, Lisbon, Portugal *Both authors contributed equally to the manuscriptAbstract: Urinary tract obstruction is a frequent cause of renal impairment. The physiopathology of obstructive nephropathy has long been viewed as a mere mechanical problem. However, recent advances in cell and systems biology have disclosed a complex physiopathology involving a high number of molecular mediators of injury that lead to cellular processes of apoptotic cell death, cell injury leading to inflammation and resultant fibrosis. Functional studies in animal models of ureteral obstruction using a variety of techniques that include genetically modified animals have disclosed an important role for the renin-angiotensin system, transforming growth factor-β1 (TGF-β1 and other mediators of inflammation in this process. In addition, high throughput techniques such as proteomics and transcriptomics have identified potential biomarkers that may guide clinical decision-making.Keywords: urinary tract obstruction, renal injury, fluid mechanics, molecular cell biology

  19. Hemolytic mechanism of dioscin proposed by molecular dynamics simulations.

    Science.gov (United States)

    Lin, Fu; Wang, Renxiao

    2010-01-01

    Saponins are a class of compounds containing a triterpenoid or steroid core with some attached carbohydrate modules. Many saponins cause hemolysis. However, the hemolytic mechanism of saponins at the molecular level is not yet fully understood. In an attempt to explore this issue, we have studied dioscin-a saponin with high hemolytic activity-through extensive molecular dynamics (MD) simulations. Firstly, all-atom MD simulations of 8 ns duration were conducted to study the stability of the dioscin-cholesterol complex and the cholesterol-cholesterol complex in water and in decane, respectively. MM-GB/SA computations indicate that the dioscin-cholesterol complex is energetically more favorable than the cholesterol-cholesterol complex in a non-polar environment. Next, several coarse-grained MD simulations of 400 ns duration were conducted to directly observe the distribution of multiple dioscin molecules on a DPPC-POPC-PSM-CHOL lipid bilayer. Our results indicate that dioscin can penetrate into the lipid bilayer, accumulate in the lipid raft micro-domain, and then bind cholesterol. This leads to the destabilization of lipid raft and consequent membrane curvature, which may eventually result in the hemolysis of red cells. This possible mechanism of hemolysis can well explain some experimental observations on hemolysis. PMID:19513766

  20. Molecular mechanisms of the plant heat stress response

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Ai-Li; Ding, Yan-Fei; Jiang, Qiong [China Jiliang University, Xueyuan Road 258, Hangzhou 310018 (China); Zhu, Cheng, E-mail: pzhch@cjlu.edu.cn [China Jiliang University, Xueyuan Road 258, Hangzhou 310018 (China)

    2013-03-08

    Highlights: ► This review elaborates the response networks of heat stress in plants. ► It elaborates proteins responding to heat stress in special physiological period. ► The proteins and pathways have formed a basic network of the heat stress response. ► Achievements of the various technologies are also combined. -- Abstract: High temperature has become a global concern, which seriously affects the growth and production of plants, particularly crops. Thus, the molecular mechanism of the heat stress response and breeding of heat-tolerant plants is necessary to protect food production and ensure crop safety. This review elaborates on the response networks of heat stress in plants, including the Hsf and Hsp response pathways, the response of ROS and the network of the hormones. In addition, the production of heat stress response elements during particular physiological periods of the plant is described. We also discuss the existing problems and future prospects concerning the molecular mechanisms of the heat stress response in plants.

  1. Molecular Fundaments of Mechanical Properties of Spider Silk

    Institute of Scientific and Technical Information of China (English)

    潘志娟; 刘敏; 李春萍; 李栋高; 盛家镛

    2003-01-01

    Dragline,framework and cocoon silk fibers of Araneus Ventricosus were used for this study.To investigate the microstructure mechanisms of stress-strain behavior of spider silk,firstly,amino acid compositions were analyzed and molecular conformations and crystallinity were measured with Raman spectra and X-ray diffraction respectively.The results showed that there were more amino acids with large side groups and polar ones in spider silk than those of Bombyx silk,and the amino acid distribution varied with different spider silk.The molecular structures were mainly α-helix and β-sheet,and random coil and β-turn existed as well.The proportions and arrangement of these conformations of dragline silk were different from framework and cocoon silk fibers.Microstructure was one of important factors of excellent mechanical properties of spider silk.Crystallinity of spider silk was very low,which implied that the roles of crystal on spider silk were not as great as other protein fibers.

  2. B-Raf mutation: a key player in molecular biology of cancer.

    Science.gov (United States)

    Rahman, M A; Salajegheh, A; Smith, R A; Lam, A K-Y

    2013-12-01

    B-Raf is one of the more commonly mutated proto-oncogenes implicated in the development of cancers. In this review, we consider the mechanisms and clinical impacts of B-Raf mutations in cancer and discuss the implications for the patient in melanoma, thyroid cancer and colorectal cancer, where B-Raf mutations are particularly common.

  3. Tryptophan metabolism in breast cancers: molecular imaging and immunohistochemistry studies

    International Nuclear Information System (INIS)

    Introduction: Tryptophan oxidation via the kynurenine pathway is an important mechanism of tumoral immunoresistance. Increased tryptophan metabolism via the serotonin pathway has been linked to malignant progression in breast cancer. In this study, we combined quantitative positron emission tomography (PET) with tumor immunohistochemistry to analyze tryptophan transport and metabolism in breast cancer. Methods: Dynamic α-[11C]methyl-L-tryptophan (AMT) PET was performed in nine women with stage II–IV breast cancer. PET tracer kinetic modeling was performed in all tumors. Expression of L-type amino acid transporter 1 (LAT1), indoleamine 2,3-dioxygenase (IDO; the initial and rate-limiting enzyme of the kynurenine pathway) and tryptophan hydroxylase 1 (TPH1; the initial enzyme of the serotonin pathway) was assessed by immunostaining of resected tumor specimens. Results: Tumor AMT uptake peaked at 5–20 min postinjection in seven tumors; the other two cases showed protracted tracer accumulation. Tumor standardized uptake values (SUVs) varied widely (2.6–9.8) and showed a strong positive correlation with volume of distribution values derived from kinetic analysis (P < .01). Invasive ductal carcinomas (n = 6) showed particularly high AMT SUVs (range, 4.7–9.8). Moderate to strong immunostaining for LAT1, IDO and TPH1 was detected in most tumor cells. Conclusions: Breast cancers show differential tryptophan kinetics on dynamic PET. SUVs measured 5–20 min postinjection reflect reasonably the tracer's volume of distribution. Further studies are warranted to determine if in vivo AMT accumulation in these tumors is related to tryptophan metabolism via the kynurenine and serotonin pathways.

  4. Molecular Biomarkers of Colorectal Cancer: A Review of Published Articles From Iran

    Directory of Open Access Journals (Sweden)

    Geramizadeh

    2015-10-01

    Full Text Available Context Colorectal cancer is one of the most common cancers worldwide (the third most common cancer in the world and is especially more common in Western countries; however, its incidence has been increased significantly during the last few years in Eastern countries such as Iran and considered as one of the five common cancers in this country. According to molecular pathways, numerous biomarkers have been identified for colorectal cancers which help patients’ management. Evidence aquisition In this study, we tried to review published articles about the molecular biomarkers of colorectal cancer from Iran. We searched medical databases such as google scholar, Scopus, PubMed, Magiran, SID and Iran Medex for keywords of “colon cancer, KRAS, BRAF, mismatch repair gene, Microsatellite instability, molecular genetics, molecular pathogenesis, biomarker and Iran” to find studies published about colorectal cancers from Iran regarding molecular biomarkers. Conclusion This study showed that molecular biomarkers in colorectal cancer of Iranian patients are not so different from Western population.

  5. Towards identification of molecular mechanisms of short stature.

    Science.gov (United States)

    Waldman, Lindsey A; Chia, Dennis J

    2013-11-20

    Growth evaluations are among the most common referrals to pediatric endocrinologists. Although a number of pathologies, both primary endocrine and non-endocrine, can present with short stature, an estimated 80% of evaluations fail to identify a clear etiology, leaving a default designation of idiopathic short stature (ISS). As a group, several features among children with ISS are suggestive of pathophysiology of the GH-IGF-1 axis, including low serum levels of IGF-1 despite normal GH secretion. Candidate gene analysis of rare cases has demonstrated that severe mutations of genes of the GH-IGF-1 axis can present with a profound height phenotype, leading to speculation that a collection of mild mutations or polymorphisms of these genes can explain poor growth in a larger proportion of patients. Recent genome-wide association studies have identified ~180 genomic loci associated with height that together account for approximately 10% of height variation. With only modest representation of the GH-IGF-1 axis, there is little support for the long-held hypothesis that common genetic variants of the hormone pathway provide the molecular mechanism for poor growth in a substantial proportion of individuals. The height-associated common variants are not observed in the anticipated frequency in the shortest individuals, suggesting rare genetic factors with large effect are more plausible in this group. As we advance towards establishing a molecular mechanism for poor growth in a greater percentage of those currently labeled ISS, we highlight two strategies that will likely be offered with increasing frequency: (1) unbiased genetic technologies including array analysis for copy number variation and whole exome/genome sequencing and (2) epigenetic alterations of key genomic loci. Ultimately data from subsets with similar molecular etiologies may emerge that will allow tailored interventions to achieve the best clinical outcome.

  6. MOLECULAR GENETIC MARKERS AS PREDICTORS OF SUPERFICIAL BLADDER CANCER

    Directory of Open Access Journals (Sweden)

    A. Yu. Babayan

    2009-01-01

    Full Text Available A system of clinical and morphological criteria is currently used to determine the pattern of superficial bladder cancer (SBC. However, this system does not completely reflect the clinical potential of SBC and needs additional markers. The purpose of this study was to search for and evaluate molecular genetic disorders as additional markers of the course of SBC. The diagnostic panel included the deletion of the loci 3р14, 9р21, 9q34, 17р13 (ТР53, mutations of exon 7 of the FGFR3 gene, and hypermethylation of the promoter regions of the RASSF1, RARB, p16, p14, CDH1 genes. The study was made on 108 matched samples (tumor/peripheral blood obtained from patients with SBC. The deletions of the loci 3р14, 9р21 and anomalous methylation of the RARb and p16 genes are markers of the worse course of SBC while FGFR3 gene mutation is a marker of better prognosis. In the context of estimation of the relapsing potential of a primary tumor, the 9p21 locus deletion is a marker associated with recurrence within the first year after malignancy resection. The group of molecular genetic markers determined by the authors for poor prognosis in combination with classical clinical and morphological criteria will specify the pattern of the course of the disease and its prognosis.

  7. The Molecular Fingerprint of High Grade Serous Ovarian Cancer Reflects Its Fallopian Tube Origin

    Directory of Open Access Journals (Sweden)

    Thomas Meyer

    2013-03-01

    Full Text Available High grade serous ovarian cancer (HGSC, the most lethal and frequent type of epithelial ovarian cancer (EOC, has poor long term prognosis due to a combination of factors: late detection, great metastatic potential and the capacity to develop resistance to available therapeutic drugs. Furthermore, there has been considerable controversy concerning the etiology of this malignancy. New studies, both clinical and molecular, strongly suggest that HGSC originates not from the surface of the ovary, but from the epithelial layer of the neighboring fallopian tube fimbriae. In this paper we summarize data supporting the central role of fallopian tube epithelium in the development of HGSC. Specifically, we address cellular pathways and regulatory mechanisms which are modulated in the process of transformation, but also genetic changes which accumulate during disease progression. Similarities between fallopian tube mucosa and the malignant tissue of HGSC warrant a closer analysis of homeostatic mechanisms in healthy epithelium in order to elucidate key steps in disease development. Finally, we highlight the importance of the cancer stem cell (CSC identification and understanding of its niche regulation for improvement of therapeutic strategies.

  8. Characterization of molecular mechanisms of in vivo UVR induced cataract.

    Science.gov (United States)

    Galichanin, Konstantin; Talebizadeh, Nooshin; Söderberg, Per

    2012-01-01

    Cataract is the leading cause of blindness in the world (1). The World Health Organization defines cataract as a clouding of the lens of the eye which impedes the transfer of light. Cataract is a multi-factorial disease associated with diabetes, smoking, ultraviolet radiation (UVR), alcohol, ionizing radiation, steroids and hypertension. There is strong experimental (2-4) and epidemiological evidence (5,6) that UVR causes cataract. We developed an animal model for UVR B induced cataract in both anesthetized (7) and non-anesthetized animals (8). The only cure for cataract is surgery but this treatment is not accessible to all. It has been estimated that a delay of onset of cataract for 10 years could reduce the need for cataract surgery by 50% (9). To delay the incidence of cataract, it is needed to understand the mechanisms of cataract formation and find effective prevention strategies. Among the mechanisms for cataract development, apoptosis plays a crucial role in initiation of cataract in humans and animals (10). Our focus has recently been apoptosis in the lens as the mechanism for cataract development (8,11,12). It is anticipated that a better understanding of the effect of UVR on the apoptosis pathway will provide possibilities for discovery of new pharmaceuticals to prevent cataract. In this article, we describe how cataract can be experimentally induced by in vivo exposure to UVR-B. Further RT-PCR and immunohistochemistry are presented as tools to study molecular mechanisms of UVR-B induced cataract. PMID:23222480

  9. Molecular Biology of Pancreatic Cancer: How Useful Is It in Clinical Practice?

    OpenAIRE

    Sakorafas, George H; Vasileios Smyrniotis

    2012-01-01

    Context During the recent two decades dramatic advances of molecular biology allowed an in-depth understanding of pancreatic carcinogenesis. It is currently accepted that pancreatic cancer has a genetic component. The real challenge is now how these impressive advances could be used in clinical practice. Objective To critically present currently available data regarding clinical application of molecular biology in pancreatic cancer. Methods Reports about clinical implications of molecular bio...

  10. Cancer chemoprevention by phytochemicals: potential molecular targets,biomarkers and animal models

    Institute of Scientific and Technical Information of China (English)

    Ki Han KWON; Avantika BARVE; Siwang YU; Mou-Tuan HUANG; Ah-Ng Tony KONG

    2007-01-01

    Recent studies have strongly indicated that certain daily-consumed dietary phytochemicals could have cancer protective effects against transgenic mice can-cer models and cancers mediated by carcinogens, irradiations and carcinogenic metabolites derived from exogenous or endogenous sources. The cancer-protec-tive effects elicited by these dietary compounds are believed to be due at least in part to the induction of cellular defense systems including the detoxifying and antioxidant enzymes system, as well as the inhibition of anti-inflammatory and anti-cell growth signaling pathways culminating in cell cycle arrest and/or cell-death. In this review, we summarize the potential mechanisms including the modu-lation of nuclear factor kappaB (NF-κB), cyclooxygenases-2 (COX-2), activator protein-1 (AP-1), mitogen-activated protein kinases (MAPKs) and the induction of phase Ⅱ cellular detoxifying and antioxidant enzymes mediated mainly by the antioxidant response elements (ARE) within the promoter regions of these genes through nuclear factor-erythroid 2-related factor 2 (Nrf2), a member of the Cap 'n' collar (CNC) family of the basic region-leucine zipper transcription factor. In addition, we also review several animal models of carcinogenesis and cancer chemopreventive efficacy studies of these animal models using dietary chemopreventive compounds. Finally, we discuss the cellular signaling cascades mediated by Nrf2, NF-κB, AP-1, MAPKs and COX-2, which have been considered to play pivotal roles in tumor initiation, promotion and progression processes,and could be promising molecular targets for the design of drugs targeting cancer prevention and therapy.

  11. COX-independent mechanisms of cancer chemoprevention by anti-inflammatory drugs

    Directory of Open Access Journals (Sweden)

    Evrim eGurpinar

    2013-07-01

    Full Text Available Epidemiological and clinical studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs, including cyclooxygenase (COX-2 selective inhibitors, reduce the risk of developing cancer. Experimental studies in human cancer cell lines and rodent models of carcinogenesis support these observations by providing strong evidence for the antineoplastic properties of NSAIDs. The involvement of COX-2 in tumorigenesis and its overexpression in various cancer tissues suggest that inhibition of COX-2 is responsible for the chemopreventive efficacy of these agents. However, the precise mechanisms by which NSAIDs exert their antiproliferative effects are still a matter of debate. Numerous other studies have shown that NSAIDs can act through COX-independent mechanisms. This review provides a detailed description of the major COX-independent molecular targets of NSAIDs and discusses how these targets may be involved in their anticancer effects. Toxicities resulting from COX inhibition and the suppression of prostaglandin synthesis preclude the long-term use of NSAIDs for cancer chemoprevention. Furthermore, chemopreventive efficacy is incomplete and treatment often leads to the development of resistance. Identification of alternative NSAID targets and elucidation of the biochemical processes by which they inhibit tumor growth could lead to the development of safer and more efficacious drugs for cancer chemoprevention.

  12. Molecular mechanisms involved in chemoresistance in paediatric acute lymphoblastic leukaemia

    Directory of Open Access Journals (Sweden)

    Stanković Tatjana

    2008-01-01

    Full Text Available Acute lymphoblastic leukaemia (ALL is the most common paediatric cancer. Despite cure rates approaching 80%, resistance to treatment and disease relapse remain a significant clinical problem. Identification of the genes and biological pathways responsible for chemoresistance is therefore crucial for the design of novel therapeutic approaches aiming to improve patient survival. Mutations in the membrane transporter P-glycoprotein genes, genetic variations in drug-metabolising enzymes and defects in apoptotic pathways are mechanisms of chemoresistance common to a wide spectrum of cancers and also play a role in paediatric ALL. In addition, several recent microarray studies have identified transcriptional profiles specifically associated with chemoresistance and pointed to a number of potentially novel therapeutic targets. These microarray studies have shown that genes discriminating between clinically responsive and resistant leukaemias tend to be involved in cellular processes such as regulation of cell cycle, proliferation, and DNA repair. Here we review the outcomes of these microarray studies and also present our own investigations into apoptotic resistance to DNA double strand breaks (DSBs in paediatric ALL. We present stratification of paediatric ALL by the profile of DNA damage response following ionising radiation (IR in vitro. This approach allows classification of ALL tumours at presentation into IR-apoptotic sensitive and IR-apoptotic resistant. Furthermore, apoptotic resistant leukaemias exhibit abnormal response of NFkB pathway following irradiation and inhibition of this pathway can sensitise leukaemic cells to IR-induced DSBs.

  13. "BreakThrough cancer Pain" biomolecular mechanisms

    Directory of Open Access Journals (Sweden)

    Francesco Amato

    2014-11-01

    Full Text Available The BTcP is a transitory exacerbation of pain of moderate to high intensity, which occurs, either spontaneously or as a result of a trigger factor, in patients with pain basic maintained for most of the day or under control of mild . The pathophysiological mechanisms underlying the development and maintenance of this type of pain seem to depend on several factors including an increase in the activity of the receptors TRPV1, central sensitization, activation of Glia etc. To better manage the disease can interfere with rapid analgesia of short duration that best overlaps the temporal characteristics of BTcP.

  14. Molecular and Epigenetic Mechanisms of MLL in Human Leukemogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Ballabio, Erica; Milne, Thomas A., E-mail: thomas.milne@imm.ox.ac.uk [MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital Headington, Oxford OX3 9DS (United Kingdom)

    2012-09-10

    Epigenetics is often defined as the study of heritable changes in gene expression or chromosome stability that don’t alter the underlying DNA sequence. Epigenetic changes are established through multiple mechanisms that include DNA methylation, non-coding RNAs and the covalent modification of specific residues on histone proteins. It is becoming clear not only that aberrant epigenetic changes are common in many human diseases such as leukemia, but that these changes by their very nature are malleable, and thus are amenable to treatment. Epigenetic based therapies have so far focused on the use of histone deacetylase (HDAC) inhibitors and DNA methyltransferase inhibitors, which tend to have more general and widespread effects on gene regulation in the cell. However, if a unique molecular pathway can be identified, diseases caused by epigenetic mechanisms are excellent candidates for the development of more targeted therapies that focus on specific gene targets, individual binding domains, or specific enzymatic activities. Designing effective targeted therapies depends on a clear understanding of the role of epigenetic mutations during disease progression. The Mixed Lineage Leukemia (MLL) protein is an example of a developmentally important protein that controls the epigenetic activation of gene targets in part by methylating histone 3 on lysine 4. MLL is required for normal development, but is also mutated in a subset of aggressive human leukemias and thus provides a useful model for studying the link between epigenetic cell memory and human disease. The most common MLL mutations are chromosome translocations that fuse the MLL gene in frame with partner genes creating novel fusion proteins. In this review, we summarize recent work that argues MLL fusion proteins could function through a single molecular pathway, but we also highlight important data that suggests instead that multiple independent mechanisms underlie MLL mediated leukemogenesis.

  15. Molecular and Epigenetic Mechanisms of MLL in Human Leukemogenesis

    Directory of Open Access Journals (Sweden)

    Thomas A. Milne

    2012-09-01

    Full Text Available Epigenetics is often defined as the study of heritable changes in gene expression or chromosome stability that don’t alter the underlying DNA sequence. Epigenetic changes are established through multiple mechanisms that include DNA methylation, non-coding RNAs and the covalent modification of specific residues on histone proteins. It is becoming clear not only that aberrant epigenetic changes are common in many human diseases such as leukemia, but that these changes by their very nature are malleable, and thus are amenable to treatment. Epigenetic based therapies have so far focused on the use of histone deacetylase (HDAC inhibitors and DNA methyltransferase inhibitors, which tend to have more general and widespread effects on gene regulation in the cell. However, if a unique molecular pathway can be identified, diseases caused by epigenetic mechanisms are excellent candidates for the development of more targeted therapies that focus on specific gene targets, individual binding domains, or specific enzymatic activities. Designing effective targeted therapies depends on a clear understanding of the role of epigenetic mutations during disease progression. The Mixed Lineage Leukemia (MLL protein is an example of a developmentally important protein that controls the epigenetic activation of gene targets in part by methylating histone 3 on lysine 4. MLL is required for normal development, but is also mutated in a subset of aggressive human leukemias and thus provides a useful model for studying the link between epigenetic cell memory and human disease. The most common MLL mutations are chromosome translocations that fuse the MLL gene in frame with partner genes creating novel fusion proteins. In this review, we summarize recent work that argues MLL fusion proteins could function through a single molecular pathway, but we also highlight important data that suggests instead that multiple independent mechanisms underlie MLL mediated leukemogenesis.

  16. MOLECULAR MECHANISM OF MICROBIAL TECHNETIUM REDUCTION FINAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    DiChristina, Thomas J. [Georgia Tech

    2013-04-30

    Microbial Tc(VII) reduction is an attractive alternative strategy for bioremediation of technetium-contaminated subsurface environments. Traditional ex situ remediation processes (e.g., adsorption or ion exchange) are often limited by poor extraction efficiency, inhibition by competing ions and production of large volumes of produced waste. Microbial Tc(VII) reduction provides an attractive alternative in situ remediation strategy since the reduced end-product Tc(IV) precipitates as TcO2, a highly insoluble hydrous oxide. Despite its potential benefits, the molecular mechanism of microbial Tc(VII) reduction remains poorly understood. The main goal of the proposed DOENABIR research project is to determine the molecular mechanism of microbial Tc(VII) reduction. Random mutagenesis studies in our lab have resulted in generation of a set of six Tc(VII) reduction-deficient mutants of Shewanella oneidensis. The anaerobic respiratory deficiencies of each Tc(VII) reduction-deficient mutant was determined by anaerobic growth on various combinations of three electron donors and 14 terminal electron acceptors. Results indicated that the electron transport pathways to Tc(VII), NO3 -, Mn(III) and U(VI) share common structural or regulatory components. In addition, we have recently found that wild-type Shewanella are also able to reduce Tc(IV) as electron acceptor, producing Tc(III) as an end-product. The recent genome sequencing of a variety of technetium-reducing bacteria and the anticipated release of several additional genome sequences in the coming year, provides us with an unprecedented opportunity to determine the mechanism of microbial technetium reduction across species and genus lines.

  17. Molecular and Epigenetic Mechanisms of MLL in Human Leukemogenesis

    International Nuclear Information System (INIS)

    Epigenetics is often defined as the study of heritable changes in gene expression or chromosome stability that don’t alter the underlying DNA sequence. Epigenetic changes are established through multiple mechanisms that include DNA methylation, non-coding RNAs and the covalent modification of specific residues on histone proteins. It is becoming clear not only that aberrant epigenetic changes are common in many human diseases such as leukemia, but that these changes by their very nature are malleable, and thus are amenable to treatment. Epigenetic based therapies have so far focused on the use of histone deacetylase (HDAC) inhibitors and DNA methyltransferase inhibitors, which tend to have more general and widespread effects on gene regulation in the cell. However, if a unique molecular pathway can be identified, diseases caused by epigenetic mechanisms are excellent candidates for the development of more targeted therapies that focus on specific gene targets, individual binding domains, or specific enzymatic activities. Designing effective targeted therapies depends on a clear understanding of the role of epigenetic mutations during disease progression. The Mixed Lineage Leukemia (MLL) protein is an example of a developmentally important protein that controls the epigenetic activation of gene targets in part by methylating histone 3 on lysine 4. MLL is required for normal development, but is also mutated in a subset of aggressive human leukemias and thus provides a useful model for studying the link between epigenetic cell memory and human disease. The most common MLL mutations are chromosome translocations that fuse the MLL gene in frame with partner genes creating novel fusion proteins. In this review, we summarize recent work that argues MLL fusion proteins could function through a single molecular pathway, but we also highlight important data that suggests instead that multiple independent mechanisms underlie MLL mediated leukemogenesis

  18. Cancer of the Pancreas: Molecular Pathways and Current Advancement in Treatment

    Science.gov (United States)

    Polireddy, Kishore; Chen, Qi

    2016-01-01

    Pancreatic cancer is one of the most lethal cancers among all malignances, with a median overall survival of cancers harbor a variety of genetic alternations that render it difficult to treat even with targeted therapy. Recent studies revealed that pancreatic cancers are highly enriched with a cancer stem cell (CSC) population, which is resistant to chemotherapeutic drugs, and therefore escapes chemotherapy and promotes tumor recurrence. Cancer cell epithelial to mesenchymal transition (EMT) is highly associated with metastasis, generation of CSCs, and treatment resistance in pancreatic cancer. Reviewed here are the molecular biology of pancreatic cancer, the major signaling pathways regulating pancreatic cancer EMT and CSCs, and the advancement in current clinical and experimental treatments for pancreatic cancer.

  19. Molecular Biology of Pancreatic Cancer: How Useful Is It in Clinical Practice?

    Directory of Open Access Journals (Sweden)

    George H Sakorafas

    2012-07-01

    Full Text Available Context During the recent two decades dramatic advances of molecular biology allowed an in-depth understanding of pancreatic carcinogenesis. It is currently accepted that pancreatic cancer has a genetic component. The real challenge is now how these impressive advances could be used in clinical practice. Objective To critically present currently available data regarding clinical application of molecular biology in pancreatic cancer. Methods Reports about clinical implications of molecular biology in patients with pancreatic cancer were retrieved from PubMed. These reports were selected on the basis of their clinical relevance, and the data of their publication (preferentially within the last 5 years. Emphasis was placed on reports investigating diagnostic, prognostic, and therapeutic implications. Results Molecular biology can be used to identify individuals at high-risk for pancreatic cancer development. Intensive surveillance is indicated in these patients to detect pancreatic neoplasia ideally at a preinvasive stage, when curative resection is still possible. Molecular biology can also be used in the diagnosis of pancreatic cancer, with molecular analysis on samples of biologic material, such as serum or plasma, duodenal fluid or preferentially pure pancreatic juice, pancreatic cells or tissue, and stools. Molecular indices have also prognostic significance. Finally, molecular biology may have therapeutic implications by using various therapeutic approaches, such as antiangiogenic factors, purine synthesis inhibitors, matrix metalloproteinase inhibitors, factors modulating tumor-stroma interaction, inactivation of the hedgehog pathway, gene therapy, oncolytic viral therapy, immunotherapy (both passive as well as active etc. Conclusion Molecular biology may have important clinical implications in patients with pancreatic cancer and represents one of the most active areas on cancer research. Hopefully clinical applications of molecular biology

  20. Systematic Analysis of Sex-Linked Molecular Alterations and Therapies in Cancer

    OpenAIRE

    Jonathan Ma; Sadhika Malladi; Beck, Andrew H.

    2016-01-01

    Though patient sex influences response to cancer treatments, little is known of the molecular causes, and cancer therapies are generally given irrespective of patient sex. We assessed transcriptomic differences in tumors from men and women spanning 17 cancer types, and we assessed differential expression between tumor and normal samples stratified by sex across 7 cancers. We used the LincsCloud platform to perform Connectivity Map analyses to link transcriptomic signatures identified in male ...