The Methanol Extract of Angelica sinensis Induces Cell Apoptosis and Suppresses Tumor Growth in Human Malignant Brain Tumors

Directory of Open Access Journals (Sweden)

Yu-Ling Lin

2013-01-01

Full Text Available Glioblastoma multiforme (GBM is a highly vascularized and invasive neoplasm. The methanol extract of Angelica sinensis (AS-M is commonly used in traditional Chinese medicine to treat several diseases, such as gastric mucosal damage, hepatic injury, menopausal symptoms, and chronic glomerulonephritis. AS-M also displays potency in suppressing the growth of malignant brain tumor cells. The growth suppression of malignant brain tumor cells by AS-M results from cell cycle arrest and apoptosis. AS-M upregulates expression of cyclin kinase inhibitors, including p16, to decrease the phosphorylation of Rb proteins, resulting in arrest at the G0-G1 phase. The expression of the p53 protein is increased by AS-M and correlates with activation of apoptosis-associated proteins. Therefore, the apoptosis of cancer cells induced by AS-M may be triggered through the p53 pathway. In in vivo studies, AS-M not only suppresses the growth of human malignant brain tumors but also significantly prolongs patient survival. In addition, AS-M has potent anticancer effects involving cell cycle arrest, apoptosis, and antiangiogenesis. The in vitro and in vivo anticancer effects of AS-M indicate that this extract warrants further investigation and potential development as a new antibrain tumor agent, providing new hope for the chemotherapy of malignant brain cancer.

Tissue distribution of aryl hydrocarbon receptor in the intestine: Implication of putative roles in tumor suppression

International Nuclear Information System (INIS)

Ikuta, Togo; Kurosumi, Masafumi; Yatsuoka, Toshimasa; Nishimura, Yoji

2016-01-01

Intestinal homeostasis is maintained by complex interactions between intestinal microorganisms and the gut immune system. Dysregulation of gut immunity may lead to inflammatory disorders and tumorigenesis. We previously have shown the tumor suppressive effects of aryl hydrocarbon receptor (AhR) in intestinal carcinogenesis. In the present study, we investigated AhR distribution in the mouse and human intestine by histochemical analysis. In the normal intestine, AhR was mainly localized in the stroma containing immune cells in the lamina propria and lymphoid follicles. On the other hand, in the tumor tissue from human colon cancer and that developed in Apc"M"i"n"/"+mice, AhR expression was elevated. AhR immunostaining was found in both stromal and tumor cells. Although AhR was localized in the cytoplasm of tumor cells in most cases, nuclear AhR was also observed in some. AhR knockdown using siRNA resulted in significant promotion of cell growth in colon cancer cell lines. Furthermore, AhR activation by AhR ligands supplemented in culture medium suppressed cell growth. Our study results suggest that tumor suppressive roles of AhR are estimated in two distinct ways: in normal tissue, AhR is associated with tumor prevention by regulating gut immunity, whereas in tumor cells, it is involved in growth suppression. - Highlights: • In the normal intestine, AhR was mainly localized in stroma containing immune cells. • In the tumor tissue, AhR expression was found in both stromal and tumor cells. • AhR knockdown promoted cell growth in colon cancer cell lines.

Tissue distribution of aryl hydrocarbon receptor in the intestine: Implication of putative roles in tumor suppression

Energy Technology Data Exchange (ETDEWEB)

Ikuta, Togo, E-mail: togo@cancer-c.pref.saitama.jp [Department of Cancer Prevention, Research Institute for Clinical Oncology, Saitama Cancer Center, 818 Komuro, Ina-machi, Kitaadachi-gun, Saitama 362-0806 (Japan); Kurosumi, Masafumi, E-mail: mkurosumi@cancer-c.pref.saitama.jp [Division of Pathology, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama 362-0806 (Japan); Yatsuoka, Toshimasa, E-mail: yatsuoka-gi@umin.ac.jp [Division of Gastroenterological Surgery, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama 362-0806 (Japan); Nishimura, Yoji, E-mail: yojinish@cancr-c.pref.saitama.jp [Division of Gastroenterological Surgery, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama 362-0806 (Japan)

2016-05-01

Intestinal homeostasis is maintained by complex interactions between intestinal microorganisms and the gut immune system. Dysregulation of gut immunity may lead to inflammatory disorders and tumorigenesis. We previously have shown the tumor suppressive effects of aryl hydrocarbon receptor (AhR) in intestinal carcinogenesis. In the present study, we investigated AhR distribution in the mouse and human intestine by histochemical analysis. In the normal intestine, AhR was mainly localized in the stroma containing immune cells in the lamina propria and lymphoid follicles. On the other hand, in the tumor tissue from human colon cancer and that developed in Apc{sup Min/+}mice, AhR expression was elevated. AhR immunostaining was found in both stromal and tumor cells. Although AhR was localized in the cytoplasm of tumor cells in most cases, nuclear AhR was also observed in some. AhR knockdown using siRNA resulted in significant promotion of cell growth in colon cancer cell lines. Furthermore, AhR activation by AhR ligands supplemented in culture medium suppressed cell growth. Our study results suggest that tumor suppressive roles of AhR are estimated in two distinct ways: in normal tissue, AhR is associated with tumor prevention by regulating gut immunity, whereas in tumor cells, it is involved in growth suppression. - Highlights: • In the normal intestine, AhR was mainly localized in stroma containing immune cells. • In the tumor tissue, AhR expression was found in both stromal and tumor cells. • AhR knockdown promoted cell growth in colon cancer cell lines.

Suppressive versus augmenting effect of the same pretreatment regimen in two murine tumor systems with distinct effector mechanisms

International Nuclear Information System (INIS)

Fujiwara, Hiromi; Hamaoka, Toshiyuki; Kitagawa, Masayasu

1978-01-01

The effect of presensitization with x-irradiated tumor cells on the development of host's immune resistance against the tumor-associated transplantation antigens (TATA) was investigated in two syngeneic tumor systems with distinct effector mechanisms. When X5563 plasmacytoma, to which immune resistance was mediated exclusively by killer T lymphocytes, was intravenously inoculated into syngeneic C3H/He mice with lower number after 7000 R x-irradiation, the mice failed to exhibit any protective immunity against the subsequent challenge with viable tumor cells. Moreover, these mice lost their capability to develop any immune resistance even after an appropriate immunization procedure. The immunodepression induced by such a pretreatment regimen was specific for X5563 tumor. While no suppressor cell activity was detected in the above pretreated mice, serum factor(s) from these mice was virtually responsible for this suppression. When the serum factor mediating this tumor-specific suppression was fractionated on the Sephadex G-200 column, the suppressive activity was found in albumin-corresponding fraction, free of any immunoglobulin component. In contrast, in MM102 mammary tumor system, in which immune resistance is solely mediated by tumor-specific antibody, the pretreatment with x-irradiated MM102 cells augmented the induction of anti-tumor immunity. These results indicate that while tumor antigens given in the form of x-irradiated tumor cells suppress the induction of killer T cell-mediated immunity in one system, the same presensitization regimen of tumor antigens augments the antibody-mediated immunity in another system, thus giving a divergent effect on the distinct effector mechanisms of syngeneic tumor immunity. (author)

Limited role of murine ATM in oncogene-induced senescence and p53-dependent tumor suppression.

Directory of Open Access Journals (Sweden)

Alejo Efeyan

Full Text Available Recent studies in human fibroblasts have provided a new general paradigm of tumor suppression according to which oncogenic signaling produces DNA damage and this, in turn, results in ATM/p53-dependent cellular senescence. Here, we have tested this model in a variety of murine experimental systems. Overexpression of oncogenic Ras in murine fibroblasts efficiently induced senescence but this occurred in the absence of detectable DNA damage signaling, thus suggesting a fundamental difference between human and murine cells. Moreover, lung adenomas initiated by endogenous levels of oncogenic K-Ras presented abundant senescent cells, but undetectable DNA damage signaling. Accordingly, K-Ras-driven adenomas were also senescent in Atm-null mice, and the tumorigenic progression of these lesions was only modestly accelerated by Atm-deficiency. Finally, we have examined chemically-induced fibrosarcomas, which possess a persistently activated DNA damage response and are highly sensitive to the activity of p53. We found that the absence of Atm favored genomic instability in the resulting tumors, but did not affect the persistent DNA damage response and did not impair p53-dependent tumor suppression. All together, we conclude that oncogene-induced senescence in mice may occur in the absence of a detectable DNA damage response. Regarding murine Atm, our data suggest that it plays a minor role in oncogene-induced senescence or in p53-dependent tumor suppression, being its tumor suppressive activity probably limited to the maintenance of genomic stability.

The Analysis of the Adverse Reaction of Traditional Chinese Medicine Tumor Bone Marrow Suppression

Science.gov (United States)

Wei, Zhenzhen; Fang, Xiaoyan; Miao, Mingsan

2018-01-01

With the rapid increase of cancer patients, chemotherapy is the main method for the clinical treatment of cancer, but also in the treatment of the adverse reactions--bone marrow suppression is often a serious infection caused by patients after chemotherapy and the important cause of mortality. Chinese medicine has obvious advantages in the prevention and treatment of bone marrow depression after chemotherapy. According to tumor bone marrow suppression after chemotherapy of etiology and pathogenesis of traditional Chinese medicine and China national knowledge internet nearly 10 years of traditional Chinese medicine in the prevention and control of the status of clinical and laboratory research of tumor bone marrow suppression, the author analyzed and summarized its characteristics, so as to provide the basis for treating bone marrow suppression of drug research and development, and promote small adverse reactions of the development and utilization of natural medicine and its preparations.

Benzyl isothiocyanate suppresses pancreatic tumor angiogenesis and invasion by inhibiting HIF-α/VEGF/Rho-GTPases: pivotal role of STAT-3.

Directory of Open Access Journals (Sweden)

Srinivas Reddy Boreddy

Full Text Available Our previous studies have shown that benzyl isothiocyanate (BITC suppresses pancreatic tumor growth by inhibiting STAT-3; however, the exact mechanism of tumor growth suppression was not clear. Here we evaluated the effects and mechanism of BITC on pancreatic tumor angiogenesis. Our results reveal that BITC significantly inhibits neovasularization on rat aorta and Chicken-Chorioallantoic membrane. Furthermore, BITC blocks the migration and invasion of BxPC-3 and PanC-1 pancreatic cancer cells in a dose dependant manner. Moreover, secretion of VEGF and MMP-2 in normoxic and hypoxic BxPC-3 and PanC-1 cells was significantly suppressed by BITC. Both VEGF and MMP-2 play a critical role in angiogenesis and metastasis. Our results reveal that BITC significantly suppresses the phosphorylation of VEGFR-2 (Tyr-1175, and expression of HIF-α. Rho-GTPases, which are regulated by VEGF play a crucial role in pancreatic cancer progression. BITC treatment reduced the expression of RhoC whereas up-regulated the expression of tumor suppressor RhoB. STAT-3 over-expression or IL-6 treatment significantly induced HIF-1α and VEGF expression; however, BITC substantially suppressed STAT-3 as well as STAT-3-induced HIF-1α and VEGF expression. Finally, in vivo tumor growth and matrigel-plug assay show reduced tumor growth and substantial reduction of hemoglobin content in the matrigel plugs and tumors of mice treated orally with 12 µmol BITC, indicating reduced tumor angiogenesis. Immunoblotting of BITC treated tumors show reduced expression of STAT-3 phosphorylation (Tyr-705, HIF-α, VEGFR-2, VEGF, MMP-2, CD31 and RhoC. Taken together, our results suggest that BITC suppresses pancreatic tumor growth by inhibiting tumor angiogenesis through STAT-3-dependant pathway.

Tumor Suppression and Promotion by Autophagy

Directory of Open Access Journals (Sweden)

Yenniffer Ávalos

2014-01-01

Full Text Available Autophagy is a highly regulated catabolic process that involves lysosomal degradation of proteins and organelles, mostly mitochondria, for the maintenance of cellular homeostasis and reduction of metabolic stress. Problems in the execution of this process are linked to different pathological conditions, such as neurodegeneration, aging, and cancer. Many of the proteins that regulate autophagy are either oncogenes or tumor suppressor proteins. Specifically, tumor suppressor genes that negatively regulate mTOR, such as PTEN, AMPK, LKB1, and TSC1/2 stimulate autophagy while, conversely, oncogenes that activate mTOR, such as class I PI3K, Ras, Rheb, and AKT, inhibit autophagy, suggesting that autophagy is a tumor suppressor mechanism. Consistent with this hypothesis, the inhibition of autophagy promotes oxidative stress, genomic instability, and tumorigenesis. Nevertheless, autophagy also functions as a cytoprotective mechanism under stress conditions, including hypoxia and nutrient starvation, that promotes tumor growth and resistance to chemotherapy in established tumors. Here, in this brief review, we will focus the discussion on this ambiguous role of autophagy in the development and progression of cancer.

Tumor suppression and promotion by autophagy.

Science.gov (United States)

Ávalos, Yenniffer; Canales, Jimena; Bravo-Sagua, Roberto; Criollo, Alfredo; Lavandero, Sergio; Quest, Andrew F G

2014-01-01

Autophagy is a highly regulated catabolic process that involves lysosomal degradation of proteins and organelles, mostly mitochondria, for the maintenance of cellular homeostasis and reduction of metabolic stress. Problems in the execution of this process are linked to different pathological conditions, such as neurodegeneration, aging, and cancer. Many of the proteins that regulate autophagy are either oncogenes or tumor suppressor proteins. Specifically, tumor suppressor genes that negatively regulate mTOR, such as PTEN, AMPK, LKB1, and TSC1/2 stimulate autophagy while, conversely, oncogenes that activate mTOR, such as class I PI3K, Ras, Rheb, and AKT, inhibit autophagy, suggesting that autophagy is a tumor suppressor mechanism. Consistent with this hypothesis, the inhibition of autophagy promotes oxidative stress, genomic instability, and tumorigenesis. Nevertheless, autophagy also functions as a cytoprotective mechanism under stress conditions, including hypoxia and nutrient starvation, that promotes tumor growth and resistance to chemotherapy in established tumors. Here, in this brief review, we will focus the discussion on this ambiguous role of autophagy in the development and progression of cancer.

Radiation Therapy Induces Macrophages to Suppress Immune Responses Against Pancreatic Tumors in Mice

Science.gov (United States)

Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Ly, Nancy Ngoc Giao; Nguy, Susanna; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Daley, Donnele; Barilla, Rocky; Tippens, Daniel; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu R.; Hajdu, Cristina; Pellicciotta, Ilenia; Oh, Philmo; Du, Kevin; Miller, George

2016-01-01

Background & Aims The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcome, compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of pre-invasive foci. Methods We investigated the effects of radiation in p48Cre;LSL-KrasG12D (KC) and p48Cre;LSLKrasG12D;LSL-Trp53R172H (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2–12 Gy and analyzed by flow cytometry. Results Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from invasive and pre-invasive pancreatic tumors had an immune-suppressive, M2-like phenotype, compared with control mice. Pancreata from mice exposed to radiation had fewer CD8+ T cells than controls and greater numbers of CD4+ T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. An antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. Conclusions Radiation exposure causes macrophages in PDAs

Gleditsia Saponin C Induces A549 Cell Apoptosis via Caspase-Dependent Cascade and Suppresses Tumor Growth on Xenografts Tumor Animal Model

Directory of Open Access Journals (Sweden)

Ye Cheng

2018-01-01

Full Text Available Saponins are natural compounds and possess the most promising anti-cancer function. Here, a saponin gleditsia saponin C (GSC, extracted from gleditsiae fructus abnormalis, could induce apoptosis of lung tumor cell line A549 via caspase dependent cascade and this effect could be prevented by the caspase inhibitors. In addition, GSC induced cell death companied with an increase ratio of Bax:Bcl-2 and inhibition of ERK and Akt signaling pathways. Meanwhile, GSC suppressed TNFα inducing NF-κB activation and increased the susceptibility of lung cancer cell to TNFα induced apoptosis. Furthermore, on mouse xenograft model, GSC significantly suppressed tumor growth and induced cancer cell apoptosis, which validated the anti-tumor effect of GSC. Based on these results, GSC might be a promising drug candidate of anti-lung cancer for its potential clinical applications.

Inhibition of BRD4 suppresses tumor growth and enhances iodine uptake in thyroid cancer

International Nuclear Information System (INIS)

Gao, Xuemei; Wu, Xinchao; Zhang, Xiao; Hua, Wenjuan; Zhang, Yajing; Maimaiti, Yusufu; Gao, Zairong; Zhang, Yongxue

2016-01-01

Thyroid cancer is a common malignancy of the endocrine system. Although radioiodine "1"3"1I treatment on differentiated thyroid cancer is widely used, many patients still fail to benefit from "1"3"1I therapy. Therefore, exploration of novel targeted therapies to suppress tumor growth and improve radioiodine uptake remains necessary. Bromodomain-containing protein 4 (BRD4) is an important member of the bromodomain and extra terminal domain family that influences transcription of downstream genes by binding to acetylated histones. In the present study, we found that BRD4 was up-regulated in thyroid cancer tissues and cell lines. Inhibition of BRD4 in thyroid cancer cells by JQ1 resulted in cell cycle arrest at G0/G1 phase and enhanced "1"3"1I uptake in vitro and suppressed tumor growth in vivo. Moreover, JQ1 treatment suppressed C-MYC but enhanced NIS expression. We further demonstrated that BRD4 was enriched in the promoter region of C-MYC, which could be markedly blocked by JQ1 treatment. In conclusion, our findings revealed that the aberrant expression of BRD4 in thyroid cancer is possibly involved in tumor progression, and JQ1 is potentially an effective chemotherapeutic agent against human thyroid cancer. - Highlights: • BRD4 is upregulated in thyroid cancer tissues and cell lines. • Inhibition of BRD4 induced cell cycle arrest and enhanced radioiodine uptake in vitro and impaired tumor growth in vivo. • JQ1 suppressed the expression of C-MYC and promoted the expression of NIS and P21. • JQ1 attenuated the recruitment of BRD4 to MYC promoter in thyroid cancer.

Inhibition of BRD4 suppresses tumor growth and enhances iodine uptake in thyroid cancer

Energy Technology Data Exchange (ETDEWEB)

Gao, Xuemei [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province (China); Hubei Province Key Laboratory of Molecular Imaging, Wuhan 430022, Hubei Province (China); Department of Urology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province (China); Wu, Xinchao [Department of Urology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province (China); Zhang, Xiao; Hua, Wenjuan; Zhang, Yajing [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province (China); Hubei Province Key Laboratory of Molecular Imaging, Wuhan 430022, Hubei Province (China); Maimaiti, Yusufu [Department of Thyroid and Breast Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province (China); Gao, Zairong, E-mail: gaobonn@163.com [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province (China); Hubei Province Key Laboratory of Molecular Imaging, Wuhan 430022, Hubei Province (China); Zhang, Yongxue [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province (China); Hubei Province Key Laboratory of Molecular Imaging, Wuhan 430022, Hubei Province (China)

2016-01-15

Thyroid cancer is a common malignancy of the endocrine system. Although radioiodine {sup 131}I treatment on differentiated thyroid cancer is widely used, many patients still fail to benefit from {sup 131}I therapy. Therefore, exploration of novel targeted therapies to suppress tumor growth and improve radioiodine uptake remains necessary. Bromodomain-containing protein 4 (BRD4) is an important member of the bromodomain and extra terminal domain family that influences transcription of downstream genes by binding to acetylated histones. In the present study, we found that BRD4 was up-regulated in thyroid cancer tissues and cell lines. Inhibition of BRD4 in thyroid cancer cells by JQ1 resulted in cell cycle arrest at G0/G1 phase and enhanced {sup 131}I uptake in vitro and suppressed tumor growth in vivo. Moreover, JQ1 treatment suppressed C-MYC but enhanced NIS expression. We further demonstrated that BRD4 was enriched in the promoter region of C-MYC, which could be markedly blocked by JQ1 treatment. In conclusion, our findings revealed that the aberrant expression of BRD4 in thyroid cancer is possibly involved in tumor progression, and JQ1 is potentially an effective chemotherapeutic agent against human thyroid cancer. - Highlights: • BRD4 is upregulated in thyroid cancer tissues and cell lines. • Inhibition of BRD4 induced cell cycle arrest and enhanced radioiodine uptake in vitro and impaired tumor growth in vivo. • JQ1 suppressed the expression of C-MYC and promoted the expression of NIS and P21. • JQ1 attenuated the recruitment of BRD4 to MYC promoter in thyroid cancer.

USP10 Antagonizes c-Myc Transcriptional Activation through SIRT6 Stabilization to Suppress Tumor Formation

Directory of Open Access Journals (Sweden)

Zhenghong Lin

2013-12-01

Full Text Available The reduced protein expression of SIRT6 tumor suppressor is involved in tumorigenesis. The molecular mechanisms underlying SIRT6 protein downregulation in human cancers remain unknown. Using a proteomic approach, we have identified the ubiquitin-specific peptidase USP10, another tumor suppressor, as one of the SIRT6-interacting proteins. USP10 suppresses SIRT6 ubiquitination to protect SIRT6 from proteasomal degradation. USP10 antagonizes the transcriptional activity of the c-Myc oncogene through SIRT6, as well as p53, to inhibit cell-cycle progression, cancer cell growth, and tumor formation. To support this conclusion, we detected significant reductions in both USP10 and SIRT6 protein expression in human colon cancers. Our study discovered crosstalk between two tumor-suppressive genes in regulating cell-cycle progression and proliferation and showed that dysregulated USP10 function promotes tumorigenesis through SIRT6 degradation.

Complement Receptor 3 Has Negative Impact on Tumor Surveillance through Suppression of Natural Killer Cell Function

Directory of Open Access Journals (Sweden)

Cheng-Fei Liu

2017-11-01

Full Text Available Complement receptor 3 (CR3 is expressed abundantly on natural killer (NK cells; however, whether it plays roles in NK cell-dependent tumor surveillance is largely unknown. Here, we show that CR3 is an important negative regulator of NK cell function, which has negative impact on tumor surveillance. Mice deficient in CR3 (CD11b−/− mice exhibited a more activated NK phenotype and had enhanced NK-dependent tumor killing. In a B16-luc melanoma-induced lung tumor growth and metastasis model, mice deficient in CR3 had reduced tumor growth and metastases, compared with WT mice. In addition, adaptive transfer of NK cells lacking CR3 (into NK-deficient mice mediated more efficient suppression of tumor growth and metastases, compared with the transfer of CR3 sufficient NK cells, suggesting that CR3 can impair tumor surveillance through suppression of NK cell function. In vitro analyses showed that engagement of CR3 with iC3b (classical CR3 ligand on NK cells negatively regulated NK cell activity and effector functions (i.e. direct tumor cell killing, antibody-dependent NK-mediated tumor killing. Cell signaling analyses showed that iC3b stimulation caused activation of Src homology 2 domain-containing inositol-5-phosphatase-1 (SHIP-1 and JNK, and suppression of ERK in NK cells, supporting that iC3b mediates negative regulation of NK cell function through its effects on SHIP-1, JNK, and ERK signal transduction pathways. Thus, our findings demonstrate a previously unknown role for CR3 in dysregulation of NK-dependent tumor surveillance and suggest that the iC3b/CR3 signaling is a critical negative regulator of NK cell function and may represent a new target for preserving NK cell function in cancer patients and improving NK cell-based therapy.

Improved MR imaging of head and neck tumors with use of fat suppression with and without Gd-DTPA

International Nuclear Information System (INIS)

Tien, R.D.; Hesselink, J.R.; Szumowski, J.; Robbins, K.T.

1990-01-01

This paper determines the feasibility of using MR fat-suppression techniques for tumors and lymphadenopathies of the head and neck. To date, 28 patients with various tumors and lymphadenopathies have been evaluated. All patients were studied with standard spin-echo T1-weighted images (T1WI) and T2-weighted images (T2WI), with and without fat-suppression technique. T1WI with Gd-DTPA and fat suppression was performed in 17 patients. Conventional and paired fat-suppression MR images were compared by means of a grading system. The post-Gd-DTPA fat-suppression T1WI and fat-suppression T2WI were found to be most useful. Fat-suppression T2WI were generally even better than post-Gd-DTPA fat-suppression T1WI in cases of squamous cell carcinoma, due to its medium contrast enhancement. Post-Gd-DTPA fat-suppression T1WI were more useful than fat-suppression T2WI in a case of plexiform neurofibroma, due to its fibrous component and lack of protons

Cystatin E/M Suppresses Tumor Cell Growth through Cytoplasmic Retention of NF-κB

Science.gov (United States)

Soh, Hendrick; Venkatesan, Natarajan; Veena, Mysore S.; Ravichandran, Sandhiya; Zinabadi, Alborz; Basak, Saroj K.; Parvatiyar, Kislay; Srivastava, Meera; Liang, Li-Jung; Gjertson, David W.; Torres, Jorge Z.; Moatamed, Neda A.

2016-01-01

We and others have shown that the cystatin E/M gene is inactivated in primary human tumors, pointing to its role as a tumor suppressor gene. However, the molecular mechanism of tumor suppression is not yet understood. Using plasmid-directed cystatin E/M gene overexpression, a lentivirus-mediated tetracycline-inducible vector system, and human papillomavirus 16 (HPV 16) E6 and E7 gene-immortalized normal human epidermal keratinocytes, we demonstrated intracellular and non-cell-autonomous apoptotic growth inhibition of tumor cell lines and that growth inhibition is associated with cytoplasmic retention of NF-κB. We further demonstrated decreased phosphorylation of IκB kinase (IKKβ) and IκBα in the presence of tumor necrosis factor alpha (TNF-α), confirming the role of cystatin E/M in the regulation of the NF-κB signaling pathway. Growth suppression of nude mouse xenograft tumors carrying a tetracycline-inducible vector system was observed with the addition of doxycycline in drinking water, confirming that the cystatin E/M gene is a tumor suppressor gene. Finally, immunohistochemical analyses of cervical carcinoma in situ and primary tumors have shown a statistically significant inverse relationship between the expression of cystatin E/M and cathepsin L and a direct relationship between the loss of cystatin E/M expression and nuclear expression of NF-κB. We therefore propose that the cystatin E/M suppressor gene plays an important role in the regulation of NF-κB. PMID:27090639

A nonlinear competitive model of the prostate tumor growth under intermittent androgen suppression.

Science.gov (United States)

Yang, Jing; Zhao, Tong-Jun; Yuan, Chang-Qing; Xie, Jing-Hui; Hao, Fang-Fang

2016-09-07

Hormone suppression has been the primary modality of treatment for prostate cancer. However long-term androgen deprivation may induce androgen-independent (AI) recurrence. Intermittent androgen suppression (IAS) is a potential way to delay or avoid the AI relapse. Mathematical models of tumor growth and treatment are simple while they are capable of capturing the essence of complicated interactions. Game theory models have analyzed that tumor cells can enhance their fitness by adopting genetically determined survival strategies. In this paper, we consider the survival strategies as the competitive advantage of tumor cells and propose a new model to mimic the prostate tumor growth in IAS therapy. Then we investigate the competition effect in tumor development by numerical simulations. The results indicate that successfully IAS-controlled states can be achieved even though the net growth rate of AI cells is positive for any androgen level. There is crucial difference between the previous models and the new one in the phase diagram of successful and unsuccessful tumor control by IAS administration, which means that the suggestions from the models for medication can be different. Furthermore we introduce quadratic logistic terms to the competition model to simulate the tumor growth in the environment with a finite carrying capacity considering the nutrients or inhibitors. The simulations show that the tumor growth can reach an equilibrium state or an oscillatory state with the net growth rate of AI cells being androgen independent. Our results suggest that the competition and the restraint of a limited environment can enhance the possibility of relapse prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radiation Therapy Induces Macrophages to Suppress T-Cell Responses Against Pancreatic Tumors in Mice.

Science.gov (United States)

Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Nguy, Susanna; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Daley, Donnele; Barilla, Rocky; Tippens, Daniel; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu R; Hajdu, Cristina; Pellicciotta, Ilenia; Oh, Philmo; Du, Kevin; Miller, George

2016-06-01

The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcomes compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of preinvasive foci. We investigated the effects of radiation therapy in p48(Cre);LSL-Kras(G12D) (KC) and p48(Cre);LSLKras(G12D);LSL-Trp53(R172H) (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony-stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2 to 12 Gy and analyzed by flow cytometry. Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from radiation treated invasive and preinvasive pancreatic tumors had an immune-suppressive, M2-like phenotype compared with control mice. Pancreata from mice exposed to radiation had fewer CD8(+) T cells than controls, and greater numbers of CD4(+) T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. A neutralizing antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. Radiation treatment causes macrophages

NF-κB RelA renders tumor-associated macrophages resistant to and capable of directly suppressing CD8+ T cells for tumor promotion.

Science.gov (United States)

Li, Liwen; Han, Lei; Sun, Fan; Zhou, Jingjiao; Ohaegbulam, Kim C; Tang, Xudong; Zang, Xingxing; Steinbrecher, Kris A; Qu, Zhaoxia; Xiao, Gutian

2018-01-01

Activation of the inflammatory transcription factor NF-κB in tumor-associated macrophages (TAMs) is assumed to contribute to tumor promotion. However, whether and how NF-κB drives the antitumor macrophages to become pro-tumorigenic have not been determined in any cancer type yet. Similarly, how TAMs repress CD8 + cytotoxic T lymphocytes (CTLs) remains largely unknown, although their importance in regulatory T (Treg) cell regulation and tumor promotion has been well appreciated. Here, using an endogenous lung cancer model we uncover a direct crosstalk between TAMs and CTLs. TAMs suppress CTLs through the T-cell inhibitory molecule B7x (B7-H4/B7S1) in a cell-cell contact manner, whereas CTLs kill TAMs in a tumor antigen-specific manner. Remarkably, TAMs secrete the known T-cell suppressive cytokine interleukin-10 (IL-10) to activate, but not to repress, CTLs. Notably, one major role of cell-intrinsic NF-κB RelA is to drive TAMs to suppress CTLs for tumor promotion. It induces B7x expression in TAMs directly, and restricts IL-10 expression indirectly by repressing expression of the NF-κB cofactor Bcl3 and subsequent Bcl3/NF-κB1-mediated transcription of IL-10. It also renders TAMs resistant to CTLs by up-regulating anti-apoptotic genes. These studies help understand how immunity is shaped in lung tumorigenesis, and suggest a RelA-targeted immunotherapy for this deadliest cancer.

Tumor-specific RNA interference targeting Pokemon suppresses tumor growth and induces apoptosis in prostate cancer.

Science.gov (United States)

Li, Yining; Xu, Shuxiong; Wang, Xiangwei; Shi, Hua; Sun, Zhaolin; Yang, Zhao

2013-02-01

To explore the exact mechanism of Pokemon in prostate cancer. Pokemon is a member of the POK family of transcriptional repressors. Its main function is suppression of the p14ARF (alternate reading frame) tumor suppressor gene. Although Pokemon expression has been found to be increased in various types of lymphoma, the exact mechanism of the gene in prostate cancer is not clear. In the present study, prostate cancer cells were transfected with the specific short hairpin ribonucleic acid (RNA) expression vector targeting Pokemon. The expression of Pokemon messenger RNA and its protein was detected by semiquantitative reverse transcriptase-polymerase chain reaction and Western blotting, respectively. The cell growth and cell apoptosis were also examined using the methyl thiazolyl tetrazolium assay and flow cytometry. The results demonstrated that specific RNA interference (RNAi) could decrease the expression levels of Pokemon gene messenger RNA and protein in prostate cancer cells. In addition, that specific RNAi significantly inhibited the cell proliferation and increased the apoptotic rate. In vivo experiments showed that specific RNAi inhibited the tumorigenicity of prostate cancer cells and significantly suppressed tumor growth. Therefore, an RNAi-targeted Pokemon gene strategy could be a potential approach to prostate cancer therapy. Copyright © 2013 Elsevier Inc. All rights reserved.

Cooperation of Ad-hING4 and 125I seed in tumor-suppression on human pancreatic cancer xenograft in nude mice

International Nuclear Information System (INIS)

Zhai Hongyan; Fa Yihua; Su Chenghai; Yang Jicheng; Sheng Weihua; Xie Yufeng

2009-01-01

This work is to investigate the combined tumor-suppression effect of Adenovirus-mediated human ING4 (Ad-hING4) and 125 I seed on human pancreatic cancer xenograft and the possible mechanisms. Ad-hING4 recombinant adenovirus vector was transected into QBI-293A cells and high titre adenovirus was obtained. Subcutaneous tumor models were established with 25 nude mice with human pancreatic cancer cell line PANC-1. They were randomly divided into 5 groups: PBS control group, Ad carrier group, 125 I seed brachytherapy group, Ad-hING4 gene treatment group, combined 125 I seed and Ad-hING4 group. The tumor volumes were measured every 5 days after treatment, and were sacrificed on the 20th day. The tumors were measured and weighed to determine the ratio of tumor-suppression and Jin-Shi q value. Morphological changes of tumor cells,the tissue injury and apoptotic index AI were examined on pathological sections. MVD, Survivin and Caspase3 were tested in immunohistochemistry. The results show that the tumor-suppressive ratio of the 125 I seed group, Ad-hING4 group, combined treatment group were,respectively, 34.19%(P 0.05). It can be concluded that 125 I seed and Ad-hING4 inhibit the growth of PANC-1 pancreatic cancer on nude mice significantly. These indicate a synergy of the combined treatments in tumor-suppression and Ad-hING4 is a promising novel radiosensitizer. The mechanisms of tumor-suppressive may be multi-pathways such as down-regulation the expression of Survivin and up-regulation the expression of Caspase3 to induce apoptosis and inhibit angiogenesis. (authors)

Cytoplasmic transfer of heritable elements other than mtDNA from SAMP1 mice into mouse tumor cells suppresses their ability to form tumors in C57BL6 mice.

Science.gov (United States)

Shimizu, Akinori; Tani, Haruna; Takibuchi, Gaku; Ishikawa, Kaori; Sakurazawa, Ryota; Inoue, Takafumi; Hashimoto, Tetsuo; Nakada, Kazuto; Takenaga, Keizo; Hayashi, Jun-Ichi

2017-11-04

In a previous study, we generated transmitochondrial P29mtSAMP1 cybrids, which had nuclear DNA from the C57BL6 (referred to as B6) mouse strain-derived P29 tumor cells and mitochondrial DNA (mtDNA) exogenously-transferred from the allogeneic strain SAMP1. Because P29mtSAMP1 cybrids did not form tumors in syngeneic B6 mice, we proposed that allogeneic SAMP1 mtDNA suppressed tumor formation of P29mtSAMP1 cybrids. To test this hypothesis, current study generated P29mt(sp)B6 cybrids carrying all genomes (nuclear DNA and mtDNA) from syngeneic B6 mice by eliminating SAMP1 mtDNA from P29mtSAMP1 cybrids and reintroducing B6 mtDNA. However, the P29mt(sp)B6 cybrids did not form tumors in B6 mice, even though they had no SAMP1 mtDNA, suggesting that SAMP1 mtDNA is not involved in tumor suppression. Then, we examined another possibility of whether SAMP1 mtDNA fragments potentially integrated into the nuclear DNA of P29mtSAMP1 cybrids are responsible for tumor suppression. We generated P29 H (sp)B6 cybrids by eliminating nuclear DNA from P29mt(sp)B6 cybrids and reintroducing nuclear DNA with no integrated SAMP1 mtDNA fragment from mtDNA-less P29 cells resistant to hygromycin in selection medium containing hygromycin. However, the P29 H (sp)B6 cybrids did not form tumors in B6 mice, even though they carried neither SAMP1 mtDNA nor nuclear DNA with integrated SAMP1 mtDNA fragments. Moreover, overproduction of reactive oxygen species (ROS) and bacterial infection were not involved in tumor suppression. These observations suggest that tumor suppression was caused not by mtDNA with polymorphic mutations or infection of cytozoic bacteria but by hypothetical heritable cytoplasmic elements other than mtDNA from SAMP1 mice. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Sunlight suppressing rejection of 280- to 320-nm UV-radiation-induced skin tumors in mice

International Nuclear Information System (INIS)

Morison, W.L.; Kelley, S.P.

1985-01-01

Repeated exposure of female C3H/HeNCR- mice to sunlight prevented the normal immunologic rejection of a UV-induced tumor. This systemic immunologic alteration was transferred to syngeneic lethally X-irradiated animals with lymphoid cells from mice exposed to sunlight. The lymphoid cells also were able to suppress the capacity of lymphoid cells from normal animals to reject a UV-induced tumor. The 295- to 320-nm wave band appeared to be responsible for this immunosuppressive effect of sunlight because suppression was prevented by filtration of the radiation through Mylar and by application of a sunscreen containing para-aminobenzoic acid. These observations may have importance in understanding the pathogenesis of sunlight-induced skin cancer in humans

Extract of Cordyceps militaris inhibits angiogenesis and suppresses tumor growth of human malignant melanoma cells.

Science.gov (United States)

Ruma, I Made Winarsa; Putranto, Endy Widya; Kondo, Eisaku; Watanabe, Risayo; Saito, Ken; Inoue, Yusuke; Yamamoto, Ken-Ichi; Nakata, Susumu; Kaihata, Masaji; Murata, Hitoshi; Sakaguchi, Masakiyo

2014-07-01

Angiogenesis is essential for tumor development and metastasis. Among several angiogenic factors, vascular endothelial growth factor receptor (VEGF) is important for tumor-derived angiogenesis and commonly overexpressed in solid tumors. Thus, many antitumor strategies targeting VEGF have been developed to inhibit cancer angiogenesis, offering insights into the successful treatment of solid cancers. However, there are a number of issues such as harmful effects on normal vascularity in clinical trials. Taking this into consideration, we employed Cordyceps militaris as an antitumor approach due to its biological safety in vivo. The herbal medicinal mushroom Cordyceps militaris has been reported to show potential anticancer properties including anti-angiogenic capacity; however, its concrete properties have yet to be fully demonstrated. In this study, we aimed to elucidate the biological role of Cordyceps militaris extract in tumor cells, especially in regulating angiogenesis and tumor growth of a human malignant melanoma cell line. We demonstrated that Cordyceps militaris extract remarkably suppressed tumor growth via induction of apoptotic cell death in culture that links to the abrogation of VEGF production in melanoma cells. This was followed by mitigation of Akt1 and GSK-3β activation, while p38α phosphorylation levels were increased. Extract treatment in mouse model xenografted with human melanoma cells resulted in a dramatic antitumor effect with down-regulation of VEGF expression. The results suggest that suppression of tumor growth by Cordyceps militaris extract is, at least, mediated by its anti-angiogenicity and apoptosis induction capacities. Cordyceps militaris extract may be a potent antitumor herbal drug for solid tumors.

Increased suppression of oncolytic adenovirus carrying mutant k5 on colorectal tumor

International Nuclear Information System (INIS)

Fan Junkai; Xiao Tian; Gu Jinfa; Wei Na; He Lingfeng; Ding Miao; Liu Xinyuan

2008-01-01

Angiogenesis plays a key role in the development of a wide variety of malignant tumors. The approach of targeting antiangiogenesis has become an important field of cancer gene therapy. In this study, the antiangiogenesis protein K5 (the kringle 5 of human plasminogen) has been mutated by changing leucine71 to arginine to form mK5. Then the ZD55-mK5, which is an oncolytic adenovirus expressing mK5, was constructed. It showed stronger inhibition on proliferation of human umbilical vein endothelial cell. Moreover, in tube formation and embryonic chorioallantoic membrane assay, ZD55-mK5 exhibited more effective antiangiogenesis than ZD55-K5. In addition, ZD55-mK5 generated obvious suppression on the growth of colorectal tumor xenografts and prolonged the life span of nude mice. These results indicate that ZD55-mK5 is a potent agent for inhibiting the tumor angiogenesis and tumor growth

Roles for miR-375 in Neuroendocrine Differentiation and Tumor Suppression via Notch Pathway Suppression in Merkel Cell Carcinoma.

Science.gov (United States)

Abraham, Karan J; Zhang, Xiao; Vidal, Ricardo; Paré, Geneviève C; Feilotter, Harriet E; Tron, Victor A

2016-04-01

Dysfunction of key miRNA pathways regulating basic cellular processes is a common driver of many cancers. However, the biological roles and/or clinical applications of such pathways in Merkel cell carcinoma (MCC), a rare but lethal cutaneous neuroendocrine (NE) malignancy, have yet to be determined. Previous work has established that miR-375 is highly expressed in MCC tumors, but its biological role in MCC remains unknown. Herein, we show that elevated miR-375 expression is a specific feature of well-differentiated MCC cell lines that express NE markers. In contrast, miR-375 is strikingly down-regulated in highly aggressive, undifferentiated MCC cell lines. Enforced miR-375 expression in these cells induced NE differentiation, and opposed cancer cell viability, migration, invasion, and survival, pointing to tumor-suppressive roles for miR-375. Mechanistically, miR-375-driven phenotypes were caused by the direct post-transcriptional repression of multiple Notch pathway proteins (Notch2 and RBPJ) linked to cancer and regulation of cell fate. Thus, we detail a novel molecular axis linking tumor-suppressive miR-375 and Notch with NE differentiation and cancer cell behavior in MCC. Our findings identify miR-375 as a putative regulator of NE differentiation, provide insight into the cell of origin of MCC, and suggest that miR-375 silencing may promote aggressive cancer cell behavior through Notch disinhibition. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Role of Gd-DTPA enhanced fat-suppression MR imaging on ovarian tumors

International Nuclear Information System (INIS)

Kang, Heoung Keun; Moon, Woong Jae; Seo, Jeong Jin; Kim, Jae Kyu; Park, Jin Gyoon; Choi, Ho Sun

1995-01-01

To determine the value of Gd-DTPA enhanced fat-suppression (GEFS) MR imaging in the characterization and differentiation of benign from malignant ovarian tumors. MRI findings of thirty-seven patients with surgically proved 44 ovarian tumors (30 benign, 14 malignant) were studied retrospectively. MR imaging with conventional spin echo (CSE; T1-weighted image TR/TE 450/20, T2-weighted image TR/TE 3500/30, 90) and GEFS were performed with a 1.5T GE signa. MRI findings of tumors including cystic or solid, wall and septal thickness, necrosis, invasion to adjacent organ, ascites and lymphadenopathy were assessed separately by using CSE and GEFS images, and then tumors were characterized as benign or malignant. Compared with CSE image, GEFS MR image showed better visualization of solid component in 5 malignant lesions, wall thickness in 5 malignant and 1 benign lesions, septal thickness in 3 malignant and 1 benign lesions, necrosis in 1 malignant lesion, and adjacent soft tissue invasion in 5 malignant lesions. Correct characterization of malignant tumors was increased from 71% on CSE image to 93% on GEFS image. However, correct characterization of benign tumors was 93% on both images. GEFS MR imaging could be useful for characterization of ovarian tumors, especially in malignant cases, and employed for differentiation of benign from malignant tumors

Type I collagen gene suppresses tumor growth and invasion of malignant human glioma cells

Directory of Open Access Journals (Sweden)

Miyata Teruo

2007-06-01

Full Text Available Abstract Background Invasion is a hallmark of a malignant tumor, such as a glioma, and the progression is followed by the interaction of tumor cells with an extracellular matrix (ECM. This study examined the role of type I collagen in the invasion of the malignant human glioma cell line T98G by the introduction of the human collagen type I α1 (HCOL1A1 gene. Results The cells overexpressing HCOL1A1 were in a cluster, whereas the control cells were scattered. Overexpression of HCOL1A1 significantly suppressed the motility and invasion of the tumor cells. The glioma cell growth was markedly inhibited in vitro and in vivo by the overexpression of HCOL1A1; in particular, tumorigenicity completely regressed in nude mice. Furthermore, the HCOL1A1 gene induced apoptosis in glioma cells. Conclusion These results indicate that HCOL1A1 have a suppressive biological function in glioma progression and that the introduction of HCOL1A1 provides the basis of a novel therapeutic approach for the treatment of malignant human glioma.

Exosome derived from epigallocatechin gallate treated breast cancer cells suppresses tumor growth by inhibiting tumor-associated macrophage infiltration and M2 polarization

International Nuclear Information System (INIS)

Jang, Ji-Young; Lee, Jong-Kuen; Jeon, Yoon-Kyung; Kim, Chul-Woo

2013-01-01

Tumor-associated macrophages (TAM) play an important role in tumor microenvironment. Particularly, M2 macrophages contribute to tumor progression, depending on the expression of NF-κB. Tumor-derived exosomes can modulate tumor microenvironment by transferring miRNAs to immune cells. Epigallocatechin gallate (EGCG) has well known anti-tumor effects; however, no data are available on the influence of EGCG on communication with cancer cells and TAM. Murine breast cancer cell lines, 4T1, was used for in vivo and ex vivo studies. Exosome was extracted from EGCG-treated 4T1 cells, and the change of miRNAs was screened using microarray. Tumor cells or TAM isolated from murine tumor graft were incubated with exosomes derived from EGCG-treated and/or miR-16 inhibitor-transfected 4T1 cells. Chemokines for monocytes (CSF-1 and CCL-2), cytokines both with high (IL-6 and TGF-β) and low (TNF-α) expression in M2 macrophages, and molecules in NF-κB pathway (IKKα and Iκ-B) were evaluated by RT-qPCR or western blot. EGCG suppressed tumor growth in murine breast cancer model, which was associated with decreased TAM and M2 macrophage infiltration. Expression of chemokine for monocytes (CSF-1 and CCL-2) were low in tumor cells from EGCG-treated mice, and cytokines of TAM was skewed from M2- into M1-like phenotype by EGCG as evidenced by decreased IL-6 and TGF-β and increased TNF-α. Ex vivo incubation of isolated tumor cells with EGCG inhibited the CSF-1 and CCL-2 expression. Ex vivo incubation of TAM with exosomes from EGCG-treated 4T1 cells led to IKKα suppression and concomitant I-κB accumulation; increase of IL-6 and TGF-β; and, decrease of TNF-α. EGCG up-regulated miR-16 in 4T1 cells and in the exosomes. Treatment of tumor cells or TAM with exosomes derived from EGCG-treated and miR-16-knock-downed 4T1 cells restored the above effects on chemokines, cytokines, and NF-κB pathway elicited by EGCG-treated exosomes. Our data demonstrate that EGCG up-regulates miR-16 in

Suppression of tumor growth and angiogenesis by a specific antagonist of the cell-surface expressed nucleolin.

Directory of Open Access Journals (Sweden)

Damien Destouches

Full Text Available BACKGROUND: Emerging evidences suggest that nucleolin expressed on the cell surface is implicated in growth of tumor cells and angiogenesis. Nucleolin is one of the major proteins of the nucleolus, but it is also expressed on the cell surface where is serves as a binding protein for variety of ligands implicated in cell proliferation, differentiation, adhesion, mitogenesis and angiogenesis. METHODOLOGY/PRINCIPAL FINDINGS: By using a specific antagonist that binds the C-terminal tail of nucleolin, the HB-19 pseudopeptide, here we show that the growth of tumor cells and angiogenesis are suppressed in various in vitro and in vivo experimental models. HB-19 inhibited colony formation in soft agar of tumor cell lines, impaired migration of endothelial cells and formation of capillary-like structures in collagen gel, and reduced blood vessel branching in the chick embryo chorioallantoic membrane. In athymic nude mice, HB-19 treatment markedly suppressed the progression of established human breast tumor cell xenografts in nude mice, and in some cases eliminated measurable tumors while displaying no toxicity to normal tissue. This potent antitumoral effect is attributed to the direct inhibitory action of HB-19 on both tumor and endothelial cells by blocking and down regulating surface nucleolin, but without any apparent effect on nucleolar nucleolin. CONCLUSION/SIGNIFICANCE: Our results illustrate the dual inhibitory action of HB-19 on the tumor development and the neovascularization process, thus validating the cell-surface expressed nucleolin as a strategic target for an effective cancer drug. Consequently, the HB-19 pseudopeptide provides a unique candidate to consider for innovative cancer therapy.

Combining fisetin and ionizing radiation suppresses the growth of mammalian colorectal cancers in xenograft tumor models.

Science.gov (United States)

Leu, Jyh-Der; Wang, Bo-Shen; Chiu, Shu-Jun; Chang, Chun-Yuan; Chen, Chien-Chih; Chen, Fu-Du; Avirmed, Shiirevnyamba; Lee, Yi-Jang

2016-12-01

Fisetin (3,7,3',4'-tetrahydroxyflavone), which belongs to the flavonoid group of polyphenols and is found in a wide range of plants, has been reported to exhibit a number of biological activities in human cancer cells, including antioxidant, anti-inflammatory, antiangiogenic, anti-invasive and antiproliferative effects. Although previous in vitro studies have shown that fisetin treatment increases the apoptotic rate and enhances the radiosensitivity of human colorectal cancer cells, the in vivo effects of fisetin on tumor growth remain unclear. In the present study a murine xenograft tumor model was employed to investigate the therapeutic effects of fisetin in combination with radiation on CT-26 colon cancer cells and human HCT116 colorectal cancer cells. This revealed that intratumoral injection of fisetin significantly suppressed the growth of CT-26 tumors compared with the untreated control group, but had little effect on the growth of HCT116 tumors. However, fisetin in combination with 2-Gy radiation enhanced tumor suppressor activity in murine colon and human colorectal xenograft tumors, as compared with 2-Gy fractionated radiation administered alone for 5 days and fisetin alone. Interestingly, fisetin downregulated the expression of the oncoprotein securin in a p53-independent manner. However, securin-null HCT116 tumors showed only moderate sensitivity to fisetin treatment, and the combination of fisetin and radiation did not significantly suppress securin-null HCT116 tumor growth compared with normal HCT116 tumors. Therefore, the role of securin in mediating the effect of fisetin on colorectal cancer growth warrants further investigation. In conclusion, the results of the current study provide important preclinical data for evaluating the efficacy of fisetin and radiation combination treatment as an adjuvant chemoradiotherapy for human colorectal cancers.

Hyaluronan suppresses prostate tumor cell proliferation through diminished expression of N-cadherin and aberrant growth factor receptor signaling

International Nuclear Information System (INIS)

Bharadwaj, Alamelu G.; Goodrich, Nathaniel P.; McAtee, Caitlin O.; Haferbier, Katie; Oakley, Gregory G.; Wahl, James K.; Simpson, Melanie A.

2011-01-01

Hyaluronan (HA) production has been functionally implicated in prostate tumorigenesis and metastasis. We previously used prostate tumor cells overexpressing the HA synthesizing enzyme HAS3 or the clinically relevant hyaluronidase Hyal1 to show that excess HA production suppresses tumor growth, while HA turnover accelerates spontaneous metastasis from the prostate. Here, we examined pathways responsible for effects of HAS3 and Hyal1 on tumor cell phenotype. Detailed characterization of cell cycle progression revealed that expression of Hyal1 accelerated cell cycle re-entry following synchronization, whereas HAS3 alone delayed entry. Hyal1 expressing cells exhibited a significant reduction in their ability to sustain ERK phosphorylation upon stimulation by growth factors, and in their expression of the cyclin-dependent kinase inhibitor p21. In contrast, HAS3 expressing cells showed prolonged ERK phosphorylation and increased expression of both p21 and p27, in asynchronous and synchronized cultures. Changes in cell cycle regulatory proteins were accompanied by HA-induced suppression of N-cadherin, while E-cadherin expression and β-catenin expression and distribution remained unchanged. Our results are consistent with a model in which excess HA synthesis suppresses cell proliferation by promoting homotypic E-cadherin mediated cell-cell adhesion, consequently signaling to elevate cell cycle inhibitor expression and suppress G1- to S-phase transition.

Treatment Combining X-Irradiation and a Ribonucleoside Anticancer Drug, TAS106, Effectively Suppresses the Growth of Tumor Cells Transplanted in Mice

International Nuclear Information System (INIS)

Yasui, Hironobu; Inanami, Osamu; Asanuma, Taketoshi; Iizuka, Daisuke; Nakajima, Takayuki; Kon, Yasuhiro; Matsuda, Akira; Kuwabara, Mikinori

2007-01-01

Purpose: To examine the in vivo antitumor efficacy of X-irradiation combined with administration of a ribonucleoside anticancer drug, 1-(3-C-ethynyl-β-D-ribo-pentofuranosyl)cytosine (TAS106, ECyd), to tumor cell-transplanted mice. Methods and Materials: Colon26 murine rectum adenocarcinoma cells and MKN45 human gastric adenocarcinoma cells were inoculated into the footpad in BALB/c mice and severe combined immunodeficient mice, respectively. They were treated with a relatively low dose of X-irradiation (2 Gy) and low amounts of TAS106 (0.1 mg/kg and 0.5 mg/kg). The tumor growth was monitored by measuring the tumor volume from Day 5 to Day 16 for Colon26 and from Day 7 to Day 20 for MKN45. Histologic analyses for proliferative and apoptotic cells in the tumors were performed using Ki-67 immunohistochemical and terminal deoxynucleotidyl transferase-mediated nick end labeling staining. The expression of survivin, a key molecule related to tumor survival, was assessed by quantitative polymerase chain reaction and immunohistochemical analysis. Results: When X-irradiation and TAS106 treatment were combined, significant inhibition of tumor growth was observed in both types of tumors compared with mice treated with X-irradiation or TAS106 alone. Marked inhibition of tumor growth was observed in half of the mice that received the combined treatment three times at 2-day intervals. Parallel to these phenomena, the suppression of survivin expression and appearance of Ki-67-negative and apoptotic cells were observed. Conclusions: X-irradiation and TAS106 effectively suppress tumor growth in mice. The inhibition of survivin expression by TAS106 is thought to mainly contribute to the suppression of the tumor growth

Clinical study on brain tumors in the aged

International Nuclear Information System (INIS)

Teramoto, Akira; Manaka, Shinya; Takakura, Kintomo

1981-01-01

In order to investigate the clinical features and the prognosis of brain tumors in the aged, 132 cases over 60 years of age were studied from the consecutive series of 1,793 brain tumors in the University of Tokyo Hospital (1963 - 1979). The incidence of brain tumors in the aged was 7.4% on the whole, while it showed a significant increase from 4.8% (1960's) to 11.5% (the later half of 1970's). Histologically, meningiomas were the most common tumors (26%), followed by neurinomas (17%), pituitary adenomas (16%) and metastatic tumors (15%). Malignant gliomas were found more frequently than benign ones. There were more meningiomas as age advanced. The proportion and the number of meningioma cases has obviously increased in recent years when CT scanners became available. Symptoms of intracranial hypertention were found less frequently in aged patients although they were still common in cases of glioblastomas. The duration from onset to surgery was relatively long, especially in cases of neurinomas and pituitary adenomas. Two cases of astrocytomas belonged to the category of silent gliomas. Overall operative mortality rate was 10.6%, while it showed a marked decrease to 4.7% in the 1970's. Five-year survival rates were as follows: meningiomas (58%), pituitary adenomas (70%), neurinomas (80%), glioblastomas (20%) and astrocytomas (25%). As for functional prognoses, 30% of the patients showed poor states on ADL, mostly because of residual psychic disorders. (author)

Regorafenib inhibits tumor progression through suppression of ERK/NF-κB activation in hepatocellular carcinoma bearing mice.

Science.gov (United States)

Weng, Mao-Chi; Wang, Mei-Hui; Tsai, Jai-Jen; Kuo, Yu-Cheng; Liu, Yu-Chang; Hsu, Fei-Ting; Wang, Hsin-Ell

2018-03-13

Regorafenib has been demonstrated in our previous study to trigger apoptosis through suppression of extracellular signal-regulated kinase (ERK)/nuclear factor-κB (NF-κB) activation in hepatocellular carcinoma (HCC) SK-Hep1 cells in vitro However, the effect of regorafenib on NF-κB-modulated tumor progression in HCC in vivo is ambiguous. The aim of the present study is to investigate the effect of regorafenib on NF-κB-modulated tumor progression in HCC bearing mouse model. pGL4.50 luciferase reporter vector transfected SK-Hep1 (SK-Hep1/ luc2 ) and Hep3B 2.1-7 tumor bearing mice were established and used for this study. Mice were treated with vehicle or regorafenib (20 mg/kg/day by gavage) for 14 days. Effects of regorafenib on tumor growth and protein expression together with toxicity of regorafenib were evaluated with digital caliper and bioluminescence imaging (BLI), ex vivo Western blotting immunohistochemistry (IHC) staining, and measurement of body weight and pathological examination of liver tissue, respectively, in SK-Hep1/ luc2 and Hep3B 2.1-7 tumor bearing mice. The results indicated regorafenib significantly reduced tumor growth and expression of phosphorylated ERK, NF-κB p65 (Ser536), phosphorylated AKT and tumor progression-associated proteins. In addition, we found regorafenib induced both extrinsic and intrinsic apoptotic pathways. Body weight and liver morphology were not affected by regorafenib treatment. Our findings present the mechanism of tumor progression inhibition by regorafenib is linked to suppression of ERK/NF-κB signaling in SK-Hep1/ luc2 and Hep3B 2.1-7 tumor-bearing mice. ©2018 The Author(s).

Wortmannin efficiently suppresses the recovery from radiation-induced damage in pimonidazole-unlabeled quiescent tumor cell population

International Nuclear Information System (INIS)

Masunaga, Shin-ichiro; Suzuki, Minoru; Kondo, Natsuko; Narabayashi, Masaru; Ono, Koji; Sakurai, Yoshinori; Tanaka, Hiroki; Maruhashi, Akira

2013-01-01

Labeling of proliferating (P) cells in mice bearing EL4 tumors was achieved by continuous administration of 5-bromo-2'-deoxyuridine (BrdU). Tumors were irradiated with γ-rays at 1 h after pimonidazole administration followed by caffeine or wortmannin treatment. Twenty-four hours later, assessment of the responses of quiescent (Q) and total (=P+Q) cell populations were based on the frequencies of micronucleation and apoptosis using immunofluorescence staining for BrdU. The response of the pimonidazole-unlabeled tumor cell fractions was assessed by means of apoptosis frequency using immunofluorescence staining for pimonidazole. The pimonidazole-unlabeled cell fraction showed significantly enhanced radio-sensitivity compared with the whole cell fraction more remarkably in Q cells than total cells. However, a significantly greater decrease in radio-sensitivity in the pimonidazole-unlabeled than the whole cell fraction, evaluated using an assay performed 24 hours after irradiation, was more clearly observed in Q cells than total cells. In both the pimonidazole-unlabeled and the whole cell fractions, wortmannin efficiently suppressed the reduction in sensitivity due to delayed assay. Wortmannin combined with γ-ray irradiation is useful for suppressing the recovery from radiation-induced damage especially in the pimonidazole-unlabeled cell fraction within the total and Q tumor cell populations. (author)

miR-137 suppresses tumor growth of malignant melanoma by targeting aurora kinase A

Energy Technology Data Exchange (ETDEWEB)

Chang, Xiao; Zhang, Haiping [Department of Dermatology and Venereal Disease, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Lian, Shi [Department of Dermatology and Venereal Disease, Capital Medical University, Beijing 100069 (China); Zhu, Wei, E-mail: zhuwei_2020@163.com [Department of Dermatology and Venereal Disease, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China)

2016-07-01

As an oncogene, aurora kinase A (AURKA) is overexpressed in various types of human cancers. However, the expression and roles of AURKA in malignant melanoma are largely unknown. In this study, a miR-137-AURKA axis was revealed to regulate melanoma growth. We found a significant increase in levels of AURKA in melanoma. Both genetic knockdown and pharmacologic inhibition of AURKA decreased tumor cell growth in vitro and in vivo. Further found that miR-137 reduced AURKA expression through interaction with its 3′ untranslated region (3′UTR) and that miR-137 was negatively correlated with AURKA expression in melanoma specimens. Overexpression of miR-137 decreased cell proliferation and colony formation in vitro. Notably, re-expression of AURKA significantly rescued miR-137-mediated suppression of cell growth and clonality. In summary, these results reveal that miR-137 functions as a tumor suppressor by targeting AURKA, providing new insights into investigation of therapeutic strategies against malignant melanoma. -- Highlights: •First reported overexpression of AURKA in melanoma. •Targeting AURKA inhibits melanoma growth in vitro and in vivo. •Further found miR-137 suppressed cell growth by binding to AURKA 3′UTR. •Re-expression of AURKA rescued miR-137-mediated suppression. •miR-137-AURKA axis may be potential therapeutic targets of melanoma.

Fast spin-echo T2-weighted MR imaging of tongue cancer; the value of fat-suppression

International Nuclear Information System (INIS)

Kim, Zu Byoung; Na, Dong Gyu; Ryoo, Jae Wook; Kim, Kyeong Ah; Byun, Hong Sik; Baek, Chung Whan; Son, Yong Ik

2000-01-01

To compare the diagnostic efficacy of fast spin-echo (FSE) T2-weighted MR imaging with and without fat suppression. Twelve patients (7 men and 5 women; mean age, 48 years) with pathologically proven cancer of the tongue were included in this study. In all of these, FSE T2-weighted MR images with and without fat suppression were obtained in the same imaging planes before surgery or biopsy. Two radiologists visually compared the images thus obtained in terms of detection, extent, and conspicuity of the tumor, and the contrast-to-noise ratio (CNR) of each tumor was also calculated. In all patients, both imaging modalities were equal in terms of tumor detection. In 4 of 12(33%), the extent of the tumor was greater with fat suppression, while in eight (67%), it was almost the same both with and without. In ten patients (83%), the tumor was more conspicuous with fat suppression, and percentage CNRs were significantly higher with fat suppression than without (180±70% and 113±61%, respectively; p=0.02). For the evaluation of patients with tongue cancer, fat-suppressed FSE T2-weighted MR imaging is superior to its conventional equivalent

Age-related decline in global form suppression

DEFF Research Database (Denmark)

Wiegand, Iris Michaela; Finke, Kathrin; Töllner, Thomas

2015-01-01

. Selective attention, i.e., the ability to focus on relevant and ignore irrelevant information, declines with increasing age; however, how this deficit affects selection of global vs. local configurations remains unknown. On this background, the present study examined for age-related differences in a global...... differences in the subsequent (250–500 ms) posterior contralateral negativity (PCN) indicated that attentional resources were allocated faster to Kanisza, as compared to non-Kanisza, targets in both age groups, while the allocation of spatial attention seemed to be generally delayed in older relative...... to younger age. Our results suggest that the enhanced global-local asymmetry in the older age group originated from less effective suppression of global distracter forms on early processing stages – indicative of older observers having difficulties with disengaging from a global default selection mode...

Age-stratified analysis of tumor markers and tumor characteristics in adolescents and young women with mature cystic teratoma

Directory of Open Access Journals (Sweden)

Huseyin Yesilyurt

2018-06-01

Full Text Available Background: Serum tumor markers are widely used for the preoperative evaluation of an adnexal mass. Elevations of cancer antigen (CA 125 and CA 19-9 have been reported in patients with mature cystic teratoma (MCT. The aim of the study is to investigate the relation of serum tumor markers with tumor characteristics in young women with MCT. Methods: We conducted a retrospective review of 157 patients under the age of 35 who underwent laparoscopic surgery for ovarian MCT. Patients were divided into two age groups: Group I (n = 80: adolescents/young adults (aged 13–25 years and Group II (n = 77: women aged 26–35 years. Data were analyzed for serum tumor markers, tumor size, and bilaterality. Results: The rates of elevated CA 125 and CA 19-9 were 10.7% and 31.5%, respectively, for Group I, and 13.9% and 26.5%, respectively, for Group II. The bilaterality rate was higher in Group II compared to Group I (19.5% vs. 8.8%, respectively, p = 0.04. Serum CA 125 and CA 19-9 elevations were not related to tumor size in Group I. In Group II, elevated levels of CA 125 were also unrelated to tumor size. However, significant elevation in CA 19-9 levels was observed when tumor size was larger than 4 cm in this age group (p = 0.004. Elevated CA 125 and CA 19-9 levels were not significantly associated with the presence of bilateral MCT in either group. Conclusion: The results of our study indicate that elevations of CA 19-9 are associated with larger tumor size in women aged 26–35 years, but not in adolescents/young adults. However, elevated serum CA 125 levels are not related to tumor size in either age group. Keywords: Adolescents, Mature cystic teratoma, Tumor marker, Tumor size, Young women

Enhanced experimental tumor metastasis with age in senescence-accelerated mouse

International Nuclear Information System (INIS)

Shimizu, Kosuke; Kinouchi Shimizu, Naomi; Asai, Tomohiro; Oku, Naoto; Tsukada, Hideo

2008-01-01

Tumor metastasis is affected by the host immune surveillance system. Since aging may attenuate the host immune potential, the experimental tumor metastasis may be enhanced with age. In the present study, we investigated this alteration of experimental tumor metastasis with age. We used senescence-accelerated mice prone 10 (SAMP10) as a model of aged animals. Natural killer cell (NK) activity, as an indicator of immune surveillance potential, in 8-month-old (aged) SAMP10 mice was observed to be much lower than that in 2-month-old (young) mice. When we examined the in vivo trafficking of lung-metastatic K1735M2 melanoma cells in SAMP10 with positron emission tomography (PET), K1735M2 cells labeled with [2- 18 F]2-deoxy-2-fluoro-D-glucose ([ 18 F]FDG) were observed in both young and aged SAMP10 just after injection of the cells, whereas the clearance of 18 F from the lungs was retarded in aged animals. The accumulation of 5-[ 125 I]iodo-2'-deoxyuridine ([ 125 I]IUdR)-labeled K1735M2 cells in the lungs of SAMP10 at 24 h after injection was significantly higher in aged mice. Corresponding to these results, the number of metastatic colonies in the lung was larger in the aged SAMP10 of the experimental tumor metastasis model. The present study demonstrated that the aging process produced a susceptible environment allowing the tumor cells to metastasize due to decrease in the host immune surveillance potential with age. (author)

ω-3 Polyunsaturated fatty acids and their cytochrome P450-derived metabolites suppress colorectal tumor development in mice.

Science.gov (United States)

Wang, Weicang; Yang, Jun; Nimiya, Yoshiki; Lee, Kin Sing Stephen; Sanidad, Katherine; Qi, Weipeng; Sukamtoh, Elvira; Park, Yeonhwa; Liu, Zhenhua; Zhang, Guodong

2017-10-01

Many studies have shown that dietary intake of ω-3 polyunsaturated fatty acids (PUFAs) reduces the risks of colorectal cancer; however, the underlying mechanisms are not well understood. Here we used a LC-MS/MS-based lipidomics to explore the role of eicosanoid signaling in the anti-colorectal cancer effects of ω-3 PUFAs. Our results showed that dietary feeding of ω-3 PUFAs-rich diets suppressed growth of MC38 colorectal tumor, and modulated profiles of fatty acids and eicosanoid metabolites in C57BL/6 mice. Notably, we found that dietary feeding of ω-3 PUFAs significantly increased levels of epoxydocosapentaenoic acids (EDPs, metabolites of ω-3 PUFA produced by cytochrome P450 enzymes) in plasma and tumor tissue of the treated mice. We further showed that systematic treatment with EDPs (dose=0.5 mg/kg per day) suppressed MC38 tumor growth in mice, with reduced expressions of pro-oncogenic genes such as C-myc, Axin2, and C-jun in tumor tissues. Together, these results support that formation of EDPs might contribute to the anti-colorectal cancer effects of ω-3 PUFAs. Copyright © 2017 Elsevier Inc. All rights reserved.

Bone Marrow Suppression by c-Kit Blockade Enhances Tumor Growth of Colorectal Metastases through the Action of Stromal Cell-Derived Factor-1

Directory of Open Access Journals (Sweden)

Kathrin Rupertus

2012-01-01

Full Text Available Background. Mobilization of c-Kit+ hematopoietic cells (HCs contributes to tumor vascularization. Whereas survival and proliferation of HCs are regulated by binding of the stem cell factor to its receptor c-Kit, migration of HCs is directed by stromal cell-derived factor (SDF-1. Therefore, targeting migration of HCs provides a promising new strategy of anti-tumor therapy. Methods. BALB/c mice (=16 were pretreated with an anti-c-Kit antibody followed by implantation of CT26.WT-GFP colorectal cancer cells into dorsal skinfold chambers. Animals (=8 additionally received a neutralizing anti-SDF-1 antibody. Animals (=8 treated with a control antibody served as controls. Investigations were performed using intravital fluorescence microscopy, immunohistochemistry, flow cytometry and western blot analysis. Results. Blockade of c-Kit significantly enhanced tumor cell engraftment compared to controls due to stimulation of tumor cell proliferation and invasion without markedly affecting tumor vascularization. C-Kit blockade significantly increased VEGF and CXCR4 expression within the growing tumors. Neutralization of SDF-1 completely antagonized this anti-c-Kit-associated tumor growth by suppression of tumor neovascularization, inhibition of tumor cell proliferation and reduction of muscular infiltration. Conclusion. Our study indicates that bone marrow suppression via anti-c-Kit pretreatment enhances tumor cell engraftment of colorectal metastases due to interaction with the SDF-1/CXCR4 pathway which is involved in HC-mediated tumor angiogenesis.

Tetrandrine Suppresses Cancer Angiogenesis and Metastasis in 4T1 Tumor Bearing Mice

Directory of Open Access Journals (Sweden)

Jian-Li Gao

2013-01-01

Full Text Available Metastasis remains the most deadly aspect of cancer and still evades direct treatment. Thus, there is a great need to develop new treatment regimens to suppress tumor cells that have escaped surgical removal or that may have already disseminated. We have found that tetrandrine (TET exhibits anticolon cancer activity. Here, we investigate the inhibition effect of TET to breast cancer metastasis, angiogenesis and its molecular basis underlying TET’s anticancer activity. We compare TET with chemotherapy drug doxorubicin in 4T1 tumor bearing BALB/c mice model and find that TET exhibits an anticancer metastatic and antiangiogenic activities better than those of doxorubicin. The lung metastatic sites were decreased by TET, which is confirmed by bioluminescence imaging in vivo. On the other hand, laser doppler perfusion imaging (LDI was used for measuring the blood flow of tumor in 4T1-tumor bearing mice. As a result, the local blood perfusion of tumor was markedly decreased by TET after 3 weeks. Mechanistically, TET treatment leads to a decrease in p-ERK level and an increase in NF-κB levels in HUVECs. TET also regulated metastatic and angiogenic related proteins, including vascular endothelial growth factor, hypoxia-inducible factor-1α, integrin β5, endothelial cell specific molecule-1, and intercellular adhesion molecule-1 in vivo.

Receptor for activated protein kinase C 1 suppresses gastric tumor progression through nuclear factor-kB pathway.

Science.gov (United States)

Yong-Zheng, X; Wan-Li, M; Ji-Ming, M; Xue-Qun, R

2015-12-01

Nuclear factor-kB (NF-kB) activity is crucial for survival and proliferation of many kinds of malignancies, including gastric cancer (GC). The receptor for activated protein kinase C 1 (RACK1) is known to regulate tumor development, whereas the underlined mechanism has not been described clearly. We analyzed expression of RACK1 in paired human GC samples by both real-time polymerase chain reaction (PCR) and western blot. Effects of RACK inhibition with small interfering RNA or its overexpression in cultured GC cell lines were evaluated in cell viabilities. NF-kB signaling was investigated using luciferase reporter assay and real-time PCR. RACK1 was significantly decreased in GC samples. Knockdown of RACK elevated GC cell viabilities, whereas overexpression of RACK1 suppressed tumorigenesis of GC cells. Importantly, NF-kB signaling was enhanced after RACK1 expression was inhibited, suggesting the negative regulation of the pro-oncogenic NF-kB activity by RACK1 might contribute to its tumor suppressor role in GC cells. Our results support that RACK1 suppresses gastric tumor progression through the NF-kB signaling pathway.

miR-129 suppresses tumor cell growth and invasion by targeting PAK5 in hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Zhai, Jian [Department II of Interventional Radiology, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200438 (China); Qu, Shuping [Department II of Special Medical Care, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200438 (China); Li, Xiaowei; Zhong, Jiaming; Chen, Xiaoxia [Department II of Interventional Radiology, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200438 (China); Qu, Zengqiang, E-mail: drquzengqiang@163.com [Department II of Interventional Radiology, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200438 (China); Wu, Dong, E-mail: wudongstc@126.com [Department II of Special Medical Care, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200438 (China)

2015-08-14

Emerging evidence suggests that microRNAs (miRNAs) play important roles in regulating HCC development and progression; however, the mechanisms by which their specific functions and mechanisms remained to be further explored. miR-129 has been reported in gastric cancers, lung cancer and colon cancer. In this study, we disclosed a new tumor suppresser function of miR-129 in HCC. We also found the downregulation of miR-129 occurred in nearly 3/4 of the tumors examined (56/76) compared with adjacent nontumorous tissues, which was more importantly, correlated to the advanced stage and vascular invasion. We then demonstrated that miR-129 overexpression attenuated HCC cells proliferation and invasion, inducing apoptosis in vitro. Moreover, we used miR-129 antagonist and found that anti-miR-129 promoted HCC cells malignant phenotypes. Mechanistically, our further investigations revealed that miR-129 suppressed cell proliferation and invasion by targeting the 3’-untranslated region of PAK5, as well as miR-129 silencing up-regulated PAK5 expression. Moreover, miR-129 expression was inversely correlated with PAK5 expression in 76 cases of HCC samples. RNA interference of PAK5 attenuated anti-miR-129 mediated cell proliferation and invasion in HCC cells. Taken together, these results demonstrated that miR-129 suppressed tumorigenesis and progression by directly targeting PAK5, defining miR-129 as a potential treatment target for HCC. - Highlights: • Decreased of miR-129 is found in HCC and associated with advanced stage and metastasis. • miR-129 suppresses proliferation and invasion of HCC cells. • miR-129 directly targets the 3′ UTR of PAK5 and diminishes PAK5 expression. • PAK5 is involved in miR-129 mediated suppression functions.

Advanced age negatively impacts survival in an experimental brain tumor model.

Science.gov (United States)

Ladomersky, Erik; Zhai, Lijie; Gritsina, Galina; Genet, Matthew; Lauing, Kristen L; Wu, Meijing; James, C David; Wainwright, Derek A

2016-09-06

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults, with an average age of 64 years at the time of diagnosis. To study GBM, a number of mouse brain tumor models have been utilized. In these animal models, subjects tend to range from 6 to 12 weeks of age, which is analogous to that of a human teenager. Here, we examined the impact of age on host immunity and the gene expression associated with immune evasion in immunocompetent mice engrafted with syngeneic intracranial GL261. The data indicate that, in mice with brain tumors, youth conveys an advantage to survival. While age did not affect the tumor-infiltrating T cell phenotype or quantity, we discovered that old mice express higher levels of the immunoevasion enzyme, IDO1, which was decreased by the presence of brain tumor. Interestingly, other genes associated with promoting immunosuppression including CTLA-4, PD-L1 and FoxP3, were unaffected by age. These data highlight the possibility that IDO1 contributes to faster GBM outgrowth with advanced age, providing rationale for future investigation into immunotherapeutic targeting in the future. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Caffeic acid phenethyl ester suppresses melanoma tumor growth by inhibiting PI3K/AKT/XIAP pathway.

Science.gov (United States)

Pramanik, Kartick C; Kudugunti, Shashi K; Fofaria, Neel M; Moridani, Majid Y; Srivastava, Sanjay K

2013-09-01

Melanoma is highly metastatic and resistant to chemotherapeutic drugs. Our previous studies have demonstrated that caffeic acid phenethyl ester (CAPE) suppresses the growth of melanoma cells and induces reactive oxygen species generation. However, the exact mechanism of the growth suppressive effects of CAPE was not clear. Here, we determined the potential mechanism of CAPE against melanoma in vivo and in vitro. Administration of 10 mg/kg/day CAPE substantially suppressed the growth of B16F0 tumor xenografts in C57BL/6 mice. Tumors from CAPE-treated mice showed reduced phosphorylation of phosphoinositide 3-kinase, AKT, mammalian target of rapamycin and protein level of X-linked inhibitor of apoptosis protein (XIAP) and enhanced the cleavage of caspase-3 and poly (ADP ribose) polymerase. In order to confirm the in vivo observations, melanoma cells were treated with CAPE. CAPE treatment suppressed the activating phosphorylation of phosphoinositide 3-kinase at Tyr 458, phosphoinositide-dependent kinase-1 at Ser 241, mammalian target of rapamycin at Ser 2448 and AKT at Ser 473 in B16F0 and SK-MEL-28 cells in a concentration and time-dependent study. Furthermore, the expression of XIAP, survivin and BCL-2 was downregulated by CAPE treatment in both cell lines. Significant apoptosis was observed by CAPE treatment as indicated by cleavage of caspase-3 and poly (ADP ribose) polymerase. AKT kinase activity was inhibited by CAPE in a concentration-dependent manner. CAPE treatment increased the nuclear translocation of XIAP, indicating increased apoptosis in melanoma cells. To confirm the involvement of reactive oxygen species in the inhibition of AKT/XIAP pathway, cells were treated with antioxidant N-acetyl-cysteine (NAC) prior to CAPE treatment. Our results indicate that NAC blocked CAPE-mediated AKT/XIAP inhibition and protected the cells from apoptosis. Because AKT regulates XIAP, their interaction was examined by immunoprecipitation studies. Our results show that CAPE

'Obligate' anaerobic Salmonella strain YB1 suppresses liver tumor growth and metastasis in nude mice.

Science.gov (United States)

Li, Chang-Xian; Yu, Bin; Shi, Lei; Geng, Wei; Lin, Qiu-Bin; Ling, Chang-Chun; Yang, Mei; Ng, Kevin T P; Huang, Jian-Dong; Man, Kwan

2017-01-01

The antitumor properties of bacteria have been demonstrated over the past decades. However, the efficacy is limited and unclear. Furthermore, systemic infection remains a serious concern in bacteria treatment. In this study, the effect of YB1, a rationally designed 'obligate' anaerobic Salmonella typhimurium strain, on liver tumor growth and metastasis in a nude mouse orthotopic liver tumor model was investigated. The orthotopic liver tumor model was established in nude mice using the hepatocellular carcinoma cell line MHCC-97L. Two weeks after orthotopic liver tumor implantation, YB1, SL7207 and saline were respectively administered through the tail vein of the mice. Longitudinal monitoring of tumor growth and metastasis was performed using Xenogen IVIS, and direct measurements of tumor volume were taken 3 weeks after treatment. In vitro , MHCC-97L and PLC cells were incubated with YB1 or SL7207 under anaerobic conditions. YB1 was observed to invade tumor cells and induce tumor cell apoptosis and death. The results revealed that all mice in the YB1 group were alive 3 weeks after YB1 injection while all mice in the SL7207 group died within 11 days of the SL7207 injection. The body weight decreased by ~9% on day 1 after YB1 injection and but subsequently recovered. Liver tumor growth and metastases were significantly inhibited following YB1 treatment. By contrast to the control group, a large number of Gr1-positive cells were detected on days 1 to 21 following YB1 treatment. Furthermore, YB1 also effectively invaded tumor cells and induced tumor cell apoptosis and death. In conclusion, YB1 suppressed liver tumor growth and metastasis in a nude mice liver tumor model. The potential mechanism may be through enhancing innate immune response and inducing tumor cell apoptosis and cell death.

Effect of host age on the transplantation, growth, and radiation response of EMT6 tumors

International Nuclear Information System (INIS)

Rockwell, S.

1981-01-01

The characteristics of EMT6 tumors in young adult and aged BALB/c KaRw mice were compared. The number of tumor cells implanted s.c. necessary to cause tumors in 50% of the injection sites was lower in aging than in young adult mice. The latent period of intradermally implanted tumors was shorter in aging mice than in young animals; however, the growth curves of established tumors were similar. The number and appearance of lung colonies after injection of cells i.v. and the pattern of spontaneous metastases were similar in young and aged animals. Radiation dose-response curves for the cells of tumors in young and aging mice were different and suggested that the proportion of hypoxic cells was higher in tumors on aging animals. These findings suggest that both immunological and nonimmunological tumor-host interactions differ in young and aged animals and that such factors may influence the natural history of the tumor and the response of the tumor to treatment

Herbal Extract SH003 Suppresses Tumor Growth and Metastasis of MDA-MB-231 Breast Cancer Cells by Inhibiting STAT3-IL-6 Signaling

Directory of Open Access Journals (Sweden)

Youn Kyung Choi

2014-01-01

Full Text Available Cancer inflammation promotes cancer progression, resulting in a high risk of cancer. Here, we demonstrate that our new herbal extract, SH003, suppresses both tumor growth and metastasis of MDA-MB-231 breast cancer cells via inhibiting STAT3-IL-6 signaling path. Our new herbal formula, SH003, mixed extract from Astragalus membranaceus, Angelica gigas, and Trichosanthes kirilowii Maximowicz, suppressed MDA-MB-231 tumor growth and lung metastasis in vivo and reduced the viability and metastatic abilities of MDA-MB-231 cells in vitro. Furthermore, SH003 inhibited STAT3 activation, which resulted in a reduction of IL-6 production. Therefore, we conclude that SH003 suppresses highly metastatic breast cancer growth and metastasis by inhibiting STAT3-IL-6 signaling path.

Tumor immunology

International Nuclear Information System (INIS)

Otter, W. den

1987-01-01

Tumor immunology, the use of immunological techniques for tumor diagnosis and approaches to immunotherapy of cancer are topics covered in this multi-author volume. Part A, 'Tumor Immunology', deals with present views on tumor-associated antigens, the initiation of immune reactions of tumor cells, effector cell killing, tumor cells and suppression of antitumor immunity, and one chapter dealing with the application of mathematical models in tumor immunology. Part B, 'Tumor Diagnosis and Imaging', concerns the use of markers to locate the tumor in vivo, for the histological diagnosis, and for the monitoring of tumor growth. In Part C, 'Immunotherapy', various experimental approaches to immunotherapy are described, such as the use of monoclonal antibodies to target drugs, the use of interleukin-2 and the use of drugs inhibiting suppression. In the final section, the evaluation, a pathologist and a clinician evaluate the possibilities and limitations of tumor immunology and the extent to which it is useful for diagnosis and therapy. refs.; figs.; tabs

Anti-progestins suppress the growth of established tumors induced by 7,12-dimethylbenz(a)anthracene: comparison between RU486 and a new 21-substituted-19-nor-progestin.

Science.gov (United States)

Wiehle, Ronald D; Christov, Konstantin; Mehta, Rajendra

2007-07-01

In this report, we evaluate the effects of a 21-substituted-19-nor-progestin, CDB-4124, on 7,12,-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis in rats in comparison with RU486. Sprague-Dawley female rats were treated with DMBA at 50 days of age in order to induce mammary tumors. When the tumors reached the size of 10-12 mm, the animals were treated for 28 days with the vehicle, RU486, progesterone, CDB-4124 at various doses, or CDB-4124 plus progesterone. Anti-progestins resulted in the regression in the size of the existing tumors, and in the suppressed development of new tumors and tumor multiplicity. Progesterone treatment, however, increased the size and multiplicity. Progesterone rendered an increased number of growing tumors as compared to the regression in the anti-progesterone treatment groups. The combination of CDB-4124 and high doses of progesterone opposed the efficacy of CDB-4124. The growth inhibitory effects of the anti-progestins were correlated with increased apoptosis and reduced cell proliferation. These results indicate that anti-progestins should be developed for the chemoprevention and treatment of hormone-responsive breast cancer.

Claudin-1 has tumor suppressive activity and is a direct target of RUNX3 in gastric epithelial cells.

Science.gov (United States)

Chang, Ti Ling; Ito, Kosei; Ko, Tun Kiat; Liu, Qiang; Salto-Tellez, Manuel; Yeoh, Khay Guan; Fukamachi, Hiroshi; Ito, Yoshiaki

2010-01-01

The transcription factor RUNX3 is a gastric tumor suppressor. Tumorigenic Runx3(-/-) gastric epithelial cells attach weakly to each other, compared with nontumorigenic Runx3(+/+) cells. We aimed to identify RUNX3 target genes that promote cell-cell contact to improve our understanding of RUNX3's role in suppressing gastric carcinogenesis. We compared gene expression profiles of Runx3(+/+) and Runx3(-/-) cells and observed down-regulation of genes associated with cell-cell adhesion in Runx3(-/-) cells. Reporter, mobility shift, and chromatin immunoprecipitation assays were used to examine the regulation of these genes by RUNX3. Tumorigenesis assays and immunohistological analyses of human gastric tumors were performed to confirm the role of the candidate genes in gastric tumor development. Mobility shift and chromatin immunoprecipitation assays revealed that the promoter activity of the gene that encodes the tight junction protein claudin-1 was up-regulated via the binding of RUNX3 to the RUNX consensus sites. The tumorigenicity of gastric epithelial cells from Runx3(-/-) mice was significantly reduced by restoration of claudin-1 expression, whereas knockdown of claudin-1 increased the tumorigenicity of human gastric cancer cells. Concomitant expression of RUNX3 and claudin-1 was observed in human normal gastric epithelium and cancers. The tight junction protein claudin-1 has gastric tumor suppressive activity and is a direct transcriptional target of RUNX3. Claudin-1 is down-regulated during the epithelial-mesenchymal transition; RUNX3 might therefore act as a tumor suppressor to antagonize the epithelial-mesenchymal transition. Copyright 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

Curcumin inhibits urothelial tumor development by suppressing IGF2 and IGF2-mediated PI3K/AKT/mTOR signaling pathway.

Science.gov (United States)

Tian, Binqiang; Zhao, Yingmei; Liang, Tao; Ye, Xuxiao; Li, Zuowei; Yan, Dongliang; Fu, Qiang; Li, Yonghui

2017-08-01

We have previously reported that curcumin inhibits urothelial tumor development in a rat bladder carcinogenesis model. In this study, we report that curcumin inhibits urothelial tumor development by suppressing IGF2 and IGF2-mediated PI3K/AKT/mTOR signaling pathway. Curcumin inhibits IGF2 expression at the transcriptional level and decreases the phosphorylation levels of IGF1R and IRS-1 in bladder cancer cells and N-methyl-N-nitrosourea (MNU)-induced urothelial tumor tissue. Ectopic expression of IGF2 and IGF1R, but not IGF1, in bladder cancer cells restored this process, suggesting that IGF2 is a target of curcumin. Moreover, introduction of constitutively active AKT1 abolished the inhibitory effect of curcumin on cell proliferation, migration, and restored the phosphorylation levels of 4E-BP1 and S6K1, suggesting that curcumin functions via suppressing IGF2-mediated AKT/mTOR signaling pathway. In summary, our results reveal that suppressing IGF2 and IGF2-mediated PI3K/AKT/mTOR signaling pathway is one of the mechanisms of action of curcumin. Our findings suggest a new therapeutic strategy against human bladder cancer caused by aberrant activation of IGF2, which are useful for translational application of curcumin.

Styrene maleic acid-encapsulated RL71 micelles suppress tumor growth in a murine xenograft model of triple negative breast cancer.

Science.gov (United States)

Martey, Orleans; Nimick, Mhairi; Taurin, Sebastien; Sundararajan, Vignesh; Greish, Khaled; Rosengren, Rhonda J

2017-01-01

Patients with triple negative breast cancer have a poor prognosis due in part to the lack of targeted therapies. In the search for novel drugs, our laboratory has developed a second-generation curcumin derivative, 3,5-bis(3,4,5-trimethoxybenzylidene)-1-methylpiperidine-4-one (RL71), that exhibits potent in vitro cytotoxicity. To improve the clinical potential of this drug, we have encapsulated it in styrene maleic acid (SMA) micelles. SMA-RL71 showed improved biodistribution, and drug accumulation in the tumor increased 16-fold compared to control. SMA-RL71 (10 mg/kg, intravenously, two times a week for 2 weeks) also significantly suppressed tumor growth compared to control in a xenograft model of triple negative breast cancer. Free RL71 was unable to alter tumor growth. Tumors from SMA-RL71-treated mice showed a decrease in angiogenesis and an increase in apoptosis. The drug treatment also modulated various cell signaling proteins including the epidermal growth factor receptor, with the mechanisms for tumor suppression consistent with previous work with RL71 in vitro. The nanoformulation was also nontoxic as shown by normal levels of plasma markers for liver and kidney injury following weekly administration of SMA-RL71 (10 mg/kg) for 90 days. Thus, we report clinical potential following encapsulation of a novel curcumin derivative, RL71, in SMA micelles.

B16 melanoma tumor growth is delayed in mice in an age-dependent manner

Directory of Open Access Journals (Sweden)

Christina Pettan-Brewer

2012-08-01

Full Text Available A major risk factor for cancer is increasing age, which suggests that syngeneic tumor implants in old mice would grow more rapidly. However, various reports have suggested that old mice are not as permissive to implanted tumor cells as young mice. In order to determine and characterize the age-related response to B16 melanoma, we implanted 5×105 tumor cells into 8, 16, 24, and 32-month-old male C57BL/6 (B6 and C57BL/6×BALB/c F1 (CB6 F1 mice subcutaneously in the inguinal and axillary spaces, or intradermally in the lateral flank. Results showed decreased tumor volume with increasing age, which varied according to mouse genetic background and the implanted site. The B6 strain showed robust tumor growth at 8 months of age at the inguinal implantation site, with an average tumor volume of 1341.25 mm3. The 16, 24, and 32-month age groups showed a decrease in tumor growth with tumor volumes of 563.69, 481.02, and 264.55 mm3, respectively (p≤0.001. The axillary implantation site was less permissive in 8-month-old B6 mice with an average tumor volume of 761.52 mm3. The 24- and 32-month age groups showed a similar decrease in tumor growth with tumor volumes of 440 and 178.19 mm3, respectively (p≤0.01. The CB6F1 strain was not as tumor permissive at 8 months of age as B6 mice with average tumor volumes of 446.96 and 426.91 mm3 for the inguinal and axillary sites, respectively. There was a decrease in tumor growth at 24 months of age at both inguinal and axillary sites with an average tumor volume of 271.02 and 249.12 mm3, respectively (p≤0.05. The strain dependence was not apparent in 8-month-old mice injected intradermally with B16 melanoma cells, with average tumor volumes of 736.82 and 842.85 mm3 for B6 and CB6 F1, respectively. However, a strain difference was seen in 32-month-old B6 mice with an average decrease in tumor volume of 250.83 mm3 (p≤0.01. In contrast, tumor growth significantly decreased earlier in CB6 F1 mice with average

Rosmarinic acid inhibits inflammation and angiogenesis of hepatocellular carcinoma by suppression of NF-κB signaling in H22 tumor-bearing mice

Directory of Open Access Journals (Sweden)

Wen Cao

2016-10-01

Full Text Available The aim of this study was to explore the anti-tumor effect and therapeutic potential of rosmarinic acid (RA in the treatment of hepatocellular carcinoma (HCC. RA at 75, 150 and 300 mg/kg was given to H22 tumor-bearing mice by intragastric administration once daily for 10 consecutive days. Levels of inflammatory and angiogenic factors, including interleukin-1β (IL-1β, interleukin-6 (IL-6, tumor necrosis factor-α (TNF-α, vascular endothelial growth factor (VEGF, and transforming growth factor-β (TGF-β were measured by enzyme linked immunosorbent assays (ELISA. Protein levels of phosphorylated NF-κB p65 and p65 were detected by western blot. mRNA level of NF-κB p65 was analyzed by qRT-PCR. The results showed that RA could effectively suppress tumor growth with fewer toxic effects by regulating the secretion of cytokines associated with inflammation and angiogenesis, and suppressing the expression of NF-κB p65 in the xenograft microenvironment. Our findings unveil the possible anti-tumor mechanisms of RA and support RA as a potential drug for the treatment of HCC.

CD147 silencing inhibits tumor growth by suppressing glucose transport in melanoma.

Science.gov (United States)

Su, Juan; Gao, Tianyuan; Jiang, Minghao; Wu, Lisha; Zeng, Weiqi; Zhao, Shuang; Peng, Cong; Chen, Xiang

2016-10-04

Melanoma is a very malignant disease and there are still no effective treatments. CD147 participates in the carcinogenesis of multiple human cancers and GLUT-1, as a glucose transporter, is associated with tumor growth. However, the function of CD147 and GLUT-1 in melanoma have not been completely understood. Thus, in this study we investigated the expression of CD147 and GLUT-1 in melanoma tissue, which were overexpressed compared with that in nevus tissue. In addition, CD147 and GLUT-1 were co-localized in the cytoplasm of human melanoma A375 cells. Immunoprecipitation proved that CD147 interacted with GLUT-1 at D105-199. Silencing CD147 by specific siRNA could downregulate GLUT-1 level via inhibiting PI3K/Akt signaling and decrease glucose uptake in A375 cells. In vivo experiments also supported that CD147 knockdown suppressed the tumor growth in melanoma subcutaneous mice model, observed by micro PET/CT. Our results could help validate CD147 as a new therapeutic target for treating melanoma.

Implication of p53-dependent cellular senescence related gene, TARSH in tumor suppression

International Nuclear Information System (INIS)

Wakoh, Takeshi; Uekawa, Natsuko; Terauchi, Kunihiko; Sugimoto, Masataka; Ishigami, Akihito; Shimada, Jun-ichi; Maruyama, Mitsuo

2009-01-01

A novel target of NESH-SH3 (TARSH) was identified as a cellular senescence related gene in mouse embryonic fibroblasts (MEFs) replicative senescence, the expression of which has been suppressed in primary clinical lung cancer specimens. However, the molecular mechanism underlying the regulation of TARSH involved in pulmonary tumorigenesis remains unclear. Here we demonstrate that the reduction of TARSH gene expression by short hairpin RNA (shRNA) system robustly inhibited the MEFs proliferation with increase in senescence-associated β-galactosidase (SA-β-gal) activity. Using p53 -/- MEFs, we further suggest that this growth arrest by loss of TARSH is evoked by p53-dependent p21 Cip1 accumulation. Moreover, we also reveal that TARSH reduction induces multicentrosome in MEFs, which is linked in chromosome instability and tumor development. These results suggest that TARSH plays an important role in proliferation of replicative senescence and may serve as a trigger of tumor development.

The role of TGFBI in mesothelioma and breast cancer: association with tumor suppression

International Nuclear Information System (INIS)

Li, Bingyan; Wen, Gengyun; Zhao, Yongliang; Tong, Jian; Hei, Tom K

2012-01-01

Transforming growth factor β induced (TGFBI) product, an extracellular matrix (ECM) protein, has been implicated as a putative tumor suppressor in recent studies. Our previous findings revealed that expression of TGFBI gene is down-regulated in a variety of cancer cell lines and clinical tissue samples. In this study, ectopic expression of TGFBI was used to ascertain its role as a tumor suppressor and to determine the underlying mechanism of mesothelioma and breast cancer. Cells were stably transfected with pRc/CMV2-TGFBI and pRc/CMV2-empty vector with Lipofectamine Plus. Ectopic expression of TGFBI was quantified by using quantitative PCR and Western-blotting. Characterization of cell viability was assessed using growth curve, clonogenic survival and soft agar growth. The potential of tumor formation was evaluated by an in vivo mouse model. Cell cycle was analyzed via flow cytometry. Expressions of p21, p53, p16 and p14 were examined using Western-blotting. Senescent cells were sorted by using a Senescence β-Galactosidase Staining Kit. Telomerase activity was measured using quantitative telomerase detection kit. In this study, an ectopic expression of TGFBI in two types of cancer cell lines, a mesothelioma cell line NCI-H28 and a breast cancer cell line MDA-MB-231 was found to have reduced the cellular growth, plating efficiency, and anchorage-independent growth. The tumorigenicity of these cancer cell lines as determined by subcutaneous inoculation in nude mice was similarly suppressed by TGFBI expression. Likewise, TGFBI expression reduced the proportion of S-phase while increased the proportion of G1 phase in these cells. The redistribution of cell cycle phase after re-expression of TGFBI was correspondent with transiently elevated expression of p21 and p53. The activities of senescence-associated β-galactosidase and telomerase were enhanced in TGFBI-transfected cells. Collectively, these results imply that TGFBI plays a suppressive role in the development

Mangiferin, a novel nuclear factor kappa B-inducing kinase inhibitor, suppresses metastasis and tumor growth in a mouse metastatic melanoma model

Energy Technology Data Exchange (ETDEWEB)

Takeda, Tomoya; Tsubaki, Masanobu; Sakamoto, Kotaro; Ichimura, Eri; Enomoto, Aya; Suzuki, Yuri [Division of Pharmacotherapy, Kinki University School of Pharmacy, Kowakae, Higashi-, Osaka (Japan); Itoh, Tatsuki [Department of Food Science and Nutrition, Kinki University School of Agriculture, Nara, Nara (Japan); Imano, Motohiro [Department of Surgery, Kinki University School of Medicine, Osakasayama, Osaka (Japan); Tanabe, Genzoh; Muraoka, Osamu [Laboratory of Pharmaceutical Organic Chemistry, School of Pharmacy, Kinki University, Kowakae, Higashi-, Osaka (Japan); Matsuda, Hideaki [Department of Natural Drugs Resources, Kinki University School of Pharmacy, Kowakae, Higashi-, Osaka (Japan); Satou, Takao [Department of Pathology, Kinki University School of Medicine, Osakasayama, Osaka (Japan); Nishida, Shozo, E-mail: nishida@phar.kindai.ac.jp [Division of Pharmacotherapy, Kinki University School of Pharmacy, Kowakae, Higashi-, Osaka (Japan)

2016-09-01

Advanced metastatic melanoma, one of the most aggressive malignancies, is currently without reliable therapy. Therefore, new therapies are urgently needed. Mangiferin is a naturally occurring glucosylxanthone and exerts many beneficial biological activities. However, the effect of mangiferin on metastasis and tumor growth of metastatic melanoma remains unclear. In this study, we evaluated the effect of mangiferin on metastasis and tumor growth in a mouse metastatic melanoma model. We found that mangiferin inhibited spontaneous metastasis and tumor growth. Furthermore, mangiferin suppressed the nuclear translocation of nuclear factor kappa B (NF-κB) and expression of phosphorylated NF-κB-inducing kinase (NIK), inhibitor of kappa B kinase (IKK), and inhibitor of kappa B (IκB) and increases the expression of IκB protein in vivo. In addition, we found that mangiferin inhibited the expression of matrix metalloproteinases (MMPs) and very late antigens (VLAs) in vivo. Mangiferin treatment also increased the expression of cleaved caspase-3, cleaved Poly ADP ribose polymerase-1 (PARP-1), p53 upregulated modulator of apoptosis (PUMA), p53, and phosphorylated p53 proteins, and decreased the expression of Survivin and Bcl-associated X (Bcl-xL) proteins in vivo. These results indicate that mangiferin selectivity suppresses the NF-κB pathway via inhibition of NIK activation, thereby inhibiting metastasis and tumor growth. Importantly, the number of reported NIK selective inhibitors is limited. Taken together, our data suggest that mangiferin may be a potential therapeutic agent with a new mechanism of targeting NIK for the treatment of metastatic melanoma. - Highlights: • Mangiferin prolongs survival in mice by inhibiting metastasis and tumor growth • Mangiferin selectivity suppresses the NF-κB pathway via inhibition of NIK activation • Mangiferin regulates the expression of MMPs, VLAs, and apoptosis regulatory proteins.

Boswellia sacra essential oil induces tumor cell-specific apoptosis and suppresses tumor aggressiveness in cultured human breast cancer cells

Science.gov (United States)

2011-01-01

Background Gum resins obtained from trees of the Burseraceae family (Boswellia sp.) are important ingredients in incense and perfumes. Extracts prepared from Boswellia sp. gum resins have been shown to possess anti-inflammatory and anti-neoplastic effects. Essential oil prepared by distillation of the gum resin traditionally used for aromatic therapy has also been shown to have tumor cell-specific anti-proliferative and pro-apoptotic activities. The objective of this study was to optimize conditions for preparing Boswellea sacra essential oil with the highest biological activity in inducing tumor cell-specific cytotoxicity and suppressing aggressive tumor phenotypes in human breast cancer cells. Methods Boswellia sacra essential oil was prepared from Omani Hougari grade resins through hydrodistillation at 78 or 100 oC for 12 hours. Chemical compositions were identified by gas chromatography-mass spectrometry; and total boswellic acids contents were quantified by high-performance liquid chromatography. Boswellia sacra essential oil-mediated cell viability and death were studied in established human breast cancer cell lines (T47D, MCF7, MDA-MB-231) and an immortalized normal human breast cell line (MCF10-2A). Apoptosis was assayed by genomic DNA fragmentation. Anti-invasive and anti-multicellular tumor properties were evaluated by cellular network and spheroid formation models, respectively. Western blot analysis was performed to study Boswellia sacra essential oil-regulated proteins involved in apoptosis, signaling pathways, and cell cycle regulation. Results More abundant high molecular weight compounds, including boswellic acids, were present in Boswellia sacra essential oil prepared at 100 oC hydrodistillation. All three human breast cancer cell lines were sensitive to essential oil treatment with reduced cell viability and elevated cell death, whereas the immortalized normal human breast cell line was more resistant to essential oil treatment. Boswellia sacra

Inhibition of Calcium-Activated Chloride Channel ANO1/TMEM16A Suppresses Tumor Growth and Invasion in Human Lung Cancer.

Directory of Open Access Journals (Sweden)

Linghan Jia

Full Text Available Lung cancer or pulmonary carcinoma is primarily derived from epithelial cells that are thin and line on the alveolar surfaces of the lung for gas exchange. ANO1/TMEM16A, initially identified from airway epithelial cells, is a member of Ca2+-activated Cl- channels (CaCCs that function to regulate epithelial secretion and cell volume for maintenance of ion and tissue homeostasis. ANO1/TMEM16A has recently been shown to be highly expressed in several epithelium originated carcinomas. However, the role of ANO1 in lung cancer remains unknown. In this study, we show that inhibition of calcium-activated chloride channel ANO1/TMEM16A suppresses tumor growth and invasion in human lung cancer. ANO1 is upregulated in different human lung cancer cell lines. Knocking-down ANO1 by small hairpin RNAs inhibited proliferation, migration and invasion of GLC82 and NCI-H520 cancel cells evaluated by CCK-8, would-healing, transwell and 3D soft agar assays. ANO1 protein is overexpressed in 77.3% cases of human lung adenocarcinoma tissues detected by immunohistochemistry. Furthermore, the tumor growth in nude mice implanted with GLC82 cells was significantly suppressed by ANO1 silencing. Taken together, our findings provide evidence that ANO1 overexpression contributes to tumor growth and invasion of lung cancer; and suppressing ANO1 overexpression may have therapeutic potential in lung cancer therapy.

Age dependency of primary tumor sites and metastases in patients with Ewing sarcoma.

Science.gov (United States)

Worch, Jennifer; Ranft, Andreas; DuBois, Steven G; Paulussen, Michael; Juergens, Heribert; Dirksen, Uta

2018-06-01

The median age of patients with Ewing sarcoma (EwS) at diagnosis is around 14-15 years. Older age is associated with a worse outcome. The correlation of age at diagnosis on sites of disease has not been fully described. The goal of this study was to evaluate the differences in sites of primary tumor and metastatic tumor involvement according to age groups. EwS data from the Gesellschaft für Pädiatrische Onkologie und Hämatology (GPOH) database of the Cooperative Ewing Sarcoma Study (CESS) 81/86 and the European Intergroup Cooperative Ewing's Sarcoma Study EICESS 92 and the EUROpean Ewing tumor Working Initiative of National Groups-99-Protocol (EURO-E.W.I.N.G.-99) study were analyzed. Patient and tumor characteristics were evaluated statistically using chi square tests. The study population included 2,635 patients with bone EwS. Sites of primary and metastatic tumors differed according to the age groups of young children (0-9 years), early adolescence (10-14 years), late adolescence (15-19 years), young adults (20-24 years), and adults (more than 24 years). Young children demonstrated the most striking differences in site of disease with a lower proportion of pelvic primary and axial tumors. They presented less often with metastatic disease at diagnosis. Site of primary and metastatic tumor involvement in EwS differs according to patient age. The biological and developmental etiology for these differences requires further investigations. © 2018 Wiley Periodicals, Inc.

Cinnamic aldehyde suppresses hypoxia-induced angiogenesis via inhibition of hypoxia-inducible factor-1α expression during tumor progression.

Science.gov (United States)

Bae, Woom-Yee; Choi, Jae-Sun; Kim, Ja-Eun; Jeong, Joo-Won

2015-11-01

During tumor progression, hypoxia-inducible factor 1 (HIF-1) plays a critical role in tumor angiogenesis and tumor growth by regulating the transcription of several genes in response to a hypoxic environment and changes in growth factors. This study was designed to investigate the effects of cinnamic aldehyde (CA) on tumor growth and angiogenesis and the mechanisms underlying CA's anti-angiogenic activities. We found that CA administration inhibits tumor growth and blocks tumor angiogenesis in BALB/c mice. In addition, CA treatment decreased HIF-1α protein expression and vascular endothelial growth factor (VEGF) expression in mouse tumors and Renca cells exposed to hypoxia in vitro. Interestingly, CA treatment did not affect the stability of von Hippel-Lindau protein (pVHL)-associated HIF-1α and CA attenuated the activation of mammalian target of rapamycin (mTOR) pathway. Collectively, these findings strongly indicate that the anti-angiogenic activity of CA is, at least in part, regulated by the mTOR pathway-mediated suppression of HIF-1α protein expression and these findings suggest that CA may be a potential drug for human cancer therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

ARF tumor suppression in the nucleolus.

Science.gov (United States)

Maggi, Leonard B; Winkeler, Crystal L; Miceli, Alexander P; Apicelli, Anthony J; Brady, Suzanne N; Kuchenreuther, Michael J; Weber, Jason D

2014-06-01

Since its discovery close to twenty years ago, the ARF tumor suppressor has played a pivotal role in the field of cancer biology. Elucidating ARF's basal physiological function in the cell has been the focal interest of numerous laboratories throughout the world for many years. Our current understanding of ARF is constantly evolving to include novel frameworks for conceptualizing the regulation of this critical tumor suppressor. As a result of this complexity, there is great need to broaden our understanding of the intricacies governing the biology of the ARF tumor suppressor. The ARF tumor suppressor is a key sensor of signals that instruct a cell to grow and proliferate and is appropriately localized in nucleoli to limit these processes. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease. Copyright © 2014 Elsevier B.V. All rights reserved.

Melatonin exerts anti-oral cancer effect via suppressing LSD1 in patient-derived tumor xenograft models

Science.gov (United States)

Yang, Cheng-Yu; Lin, Chih-Kung; Tsao, Chang-Huei; Hsieh, Cheng-Chih; Lin, Gu-Jiun; Ma, Kuo-Hsing; Shieh, Yi-Shing; Sytwu, Huey-Kang; Chen, Yuan-Wu

2017-01-01

Aberrant activation of histone lysine-specific demethylase (LSD1) increases tumorigenicity; hence, LSD1 is considered a therapeutic target for various human cancers. Although melatonin, an endogenously produced molecule, may defend against various cancers, the precise mechanism involved in its anti-oral cancer effect remains unclear. Patient-derived tumor xenograft (PDTX) models are preclinical models that can more accurately reflect human tumor biology compared with cell line xenograft models. Here, we evaluated the anticancer activity of melatonin by using LSD1-overexpressing oral cancer PDTX models. By assessing oral squamous cell carcinoma (OSCC) tissue arrays through immunohistochemistry, we examined whether aberrant LSD1 overexpression in OSCC is associated with poor prognosis. We also evaluated the action mechanism of melatonin against OSCC with lymphatic metastases by using the PDTX models. Our results indicated that melatonin, at pharmacological concentrations, significantly suppresses cell proliferation in a dose- and time-dependent manner. The observed suppression of proliferation was accompanied by the melatonin-mediated inhibition of LSD1 in oral cancer PDTXs and oral cancer cell lines. In conclusion, we determined that the beneficial effects of melatonin in reducing oral cancer cell proliferation are associated with reduced LSD1 expression in vivo and in vitro. PMID:28422711

Pentastatin-1, a collagen IV derived 20-mer peptide, suppresses tumor growth in a small cell lung cancer xenograft model.

Science.gov (United States)

Koskimaki, Jacob E; Karagiannis, Emmanouil D; Tang, Benjamin C; Hammers, Hans; Watkins, D Neil; Pili, Roberto; Popel, Aleksander S

2010-02-01

Angiogenesis is the formation of neovasculature from a pre-existing vascular network. Progression of solid tumors including lung cancer is angiogenesis-dependent. We previously introduced a bioinformatics-based methodology to identify endogenous anti-angiogenic peptide sequences, and validated these predictions in vitro in human umbilical vein endothelial cell (HUVEC) proliferation and migration assays. One family of peptides with high activity is derived from the alpha-fibrils of type IV collagen. Based on the results from the in vitro screening, we have evaluated the ability of a 20 amino acid peptide derived from the alpha5 fibril of type IV collagen, pentastatin-1, to suppress vessel growth in an angioreactor-based directed in vivo angiogenesis assay (DIVAA). In addition, pentastatin-1 suppressed tumor growth with intraperitoneal peptide administration in a small cell lung cancer (SCLC) xenograft model in nude mice using the NCI-H82 human cancer cell line. Pentastatin-1 decreased the invasion of vessels into angioreactors in vivo in a dose dependent manner. The peptide also decreased the rate of tumor growth and microvascular density in vivo in a small cell lung cancer xenograft model. The peptide treatment significantly decreased the invasion of microvessels in angioreactors and the rate of tumor growth in the xenograft model, indicating potential treatment for angiogenesis-dependent disease, and for translational development as a therapeutic agent for lung cancer.

Pentastatin-1, a collagen IV derived 20-mer peptide, suppresses tumor growth in a small cell lung cancer xenograft model

International Nuclear Information System (INIS)

Koskimaki, Jacob E; Karagiannis, Emmanouil D; Tang, Benjamin C; Hammers, Hans; Watkins, D Neil; Pili, Roberto; Popel, Aleksander S

2010-01-01

Angiogenesis is the formation of neovasculature from a pre-existing vascular network. Progression of solid tumors including lung cancer is angiogenesis-dependent. We previously introduced a bioinformatics-based methodology to identify endogenous anti-angiogenic peptide sequences, and validated these predictions in vitro in human umbilical vein endothelial cell (HUVEC) proliferation and migration assays. One family of peptides with high activity is derived from the α-fibrils of type IV collagen. Based on the results from the in vitro screening, we have evaluated the ability of a 20 amino acid peptide derived from the α5 fibril of type IV collagen, pentastatin-1, to suppress vessel growth in an angioreactor-based directed in vivo angiogenesis assay (DIVAA). In addition, pentastatin-1 suppressed tumor growth with intraperitoneal peptide administration in a small cell lung cancer (SCLC) xenograft model in nude mice using the NCI-H82 human cancer cell line. Pentastatin-1 decreased the invasion of vessels into angioreactors in vivo in a dose dependent manner. The peptide also decreased the rate of tumor growth and microvascular density in vivo in a small cell lung cancer xenograft model. The peptide treatment significantly decreased the invasion of microvessels in angioreactors and the rate of tumor growth in the xenograft model, indicating potential treatment for angiogenesis-dependent disease, and for translational development as a therapeutic agent for lung cancer

3-bromopyruvate and sodium citrate target glycolysis, suppress survivin, and induce mitochondrial-mediated apoptosis in gastric cancer cells and inhibit gastric orthotopic transplantation tumor growth.

Science.gov (United States)

Wang, Ting-An; Zhang, Xiao-Dong; Guo, Xing-Yu; Xian, Shu-Lin; Lu, Yun-Fei

2016-03-01

Glycolysis is the primary method utilized by cancer cells to produce the energy (adenosine triphosphate, ATP) required for cell proliferation. Therefore, inhibition of glycolysis may inhibit tumor growth. We previously found that both 3-bromopyruvate (3-BrPA) and sodium citrate (SCT) can inhibit glycolysis in vitro; however, the underlying inhibitory mechanisms remain unclear. In the present study, we used a human gastric cancer cell line (SGC-7901) and an orthotopic transplantation tumor model in nude mice to explore the specific mechanisms of 3-BrPA and SCT. We found that both 3-BrPA and SCT effectively suppressed cancer cell proliferation, arrested the cell cycle, induced apoptosis, and decreased the production of lactate and ATP. 3-BrPA significantly reduced the glycolytic enzyme hexokinase activity, while SCT selectively inhibited phosphofructokinase-1 activity. Furthermore, 3-BrPA and SCT upregulated the expression of pro-apoptotic proteins (Bax, cytochrome c, and cleaved caspase-3) and downregulated the expression of anti-apoptotic proteins (Bcl-2 and survivin). Finally, our animal model of gastric cancer indicated that intraperitoneal injection of 3-BrPA and SCT suppressed orthotopic transplantation tumor growth and induced tumor apoptosis. Taken together, these results suggest that 3-BrPA and SCT selectively suppress glycolytic enzymes, decrease ATP production, induce mitochondrial-mediated apoptosis, downregulate survivin, and inhibit tumor growth. Moreover, an intraperitoneal injection is an effective form of administration of 3-BrPA and SCT.

Injury Signals Cooperate with Nf1 Loss to Relieve the Tumor-Suppressive Environment of Adult Peripheral Nerve

Directory of Open Access Journals (Sweden)

Sara Ribeiro

2013-10-01

Full Text Available Schwann cells are highly plastic cells that dedifferentiate to a progenitor-like state following injury. However, deregulation of this plasticity, may be involved in the formation of neurofibromas, mixed-cell tumors of Schwann cell (SC origin that arise upon loss of NF1. Here, we show that adult myelinating SCs (mSCs are refractory to Nf1 loss. However, in the context of injury, Nf1-deficient cells display opposing behaviors along the wounded nerve; distal to the injury, Nf1−/− mSCs redifferentiate normally, whereas at the wound site Nf1−/− mSCs give rise to neurofibromas in both Nf1+/+ and Nf1+/− backgrounds. Tracing experiments showed that distinct cell types within the tumor derive from Nf1-deficient SCs. This model of neurofibroma formation demonstrates that neurofibromas can originate from adult SCs and that the nerve environment can switch from tumor suppressive to tumor promoting at a site of injury. These findings have implications for both the characterization and treatment of neurofibromas.

Dual PI3K/mTOR inhibitors, GSK2126458 and PKI-587, suppress tumor progression and increase radiosensitivity in nasopharyngeal carcinoma.

Science.gov (United States)

Liu, Tongxin; Sun, Quanquan; Li, Qi; Yang, Hua; Zhang, Yuqin; Wang, Rong; Lin, Xiaoshan; Xiao, Dong; Yuan, Yawei; Chen, Longhua; Wang, Wei

2015-02-01

Although combined chemoradiotherapy has provided considerable improvements for nasopharyngeal carcinoma (NPC), recurrence and metastasis are still frequent. The PI3K/Akt/mTOR pathway plays a critical role in tumor formation and tumor cell survival after radiation-induced DNA damage. In the present study, we evaluated whether inhibition of PI3K/mTOR by two novel dual inhibitors, GSK2126458 and PKI-587, could suppress tumor progression and sensitize NPC cells to radiation. Four NPC cell lines (CNE-1, CNE-2, 5-8F, and 6-10B) were used to analyze the effects of GSK216458 and PKI-587 on cell proliferation, migration, invasion, clonogenic survival, amount of residual γ-H2AX foci, cell cycle, and apoptosis after radiation. A 5-8F xenograft model was used to evaluate the in vivo effects of the two compounds in combination with ionizing radiation (IR). Both GSK216458 and PKI-587 effectively inhibited cell proliferation and motility in NPC cells and suppressed phosphorylation of Akt, mTOR, S6, and 4EBP1 proteins in a concentration- and time-dependent manner. Moreover, both compounds sensitized NPC cells to IR by increasing DNA damage, enhancing G2-M cell-cycle delay, and inducing apoptosis. In vivo, the combination of IR with GSK2126458 or PKI-587 significantly inhibited tumor growth. Antitumor effect was correlated with induction of apoptosis and suppression of the phosphorylation of mTOR, Akt, and 4EBP1. These new findings suggest the usefulness of PI3K/mTOR dual inhibition for antitumor and radiosensitizing. The combination of IR with a dual PI3K/mTOR inhibitor, GSK2126458 or PKI-587, might be a promising therapeutic strategy for NPC. ©2014 American Association for Cancer Research.

Spermidine Suppresses Age-Associated Memory Impairment by Preventing Adverse Increase of Presynaptic Active Zone Size and Release.

Directory of Open Access Journals (Sweden)

Varun K Gupta

2016-09-01

Full Text Available Memories are assumed to be formed by sets of synapses changing their structural or functional performance. The efficacy of forming new memories declines with advancing age, but the synaptic changes underlying age-induced memory impairment remain poorly understood. Recently, we found spermidine feeding to specifically suppress age-dependent impairments in forming olfactory memories, providing a mean to search for synaptic changes involved in age-dependent memory impairment. Here, we show that a specific synaptic compartment, the presynaptic active zone (AZ, increases the size of its ultrastructural elaboration and releases significantly more synaptic vesicles with advancing age. These age-induced AZ changes, however, were fully suppressed by spermidine feeding. A genetically enforced enlargement of AZ scaffolds (four gene-copies of BRP impaired memory formation in young animals. Thus, in the Drosophila nervous system, aging AZs seem to steer towards the upper limit of their operational range, limiting synaptic plasticity and contributing to impairment of memory formation. Spermidine feeding suppresses age-dependent memory impairment by counteracting these age-dependent changes directly at the synapse.

3D view to tumor suppression: Lkb1, polarity and the arrest of oncogenic c-Myc.

Science.gov (United States)

Partanen, Johanna I; Nieminen, Anni I; Klefstrom, Juha

2009-03-01

Machiavelli wrote, in his famous political treatise Il Principe, about disrupting organization by planting seeds of dissension or by eliminating necessary support elements. Tumor cells do exactly that by disrupting the organized architecture of epithelial cell layers during progression from contained benign tumor to full-blown invasive cancer. However, it is still unclear whether tumor cells primarily break free by activating oncogenes powerful enough to cause chaos or by eliminating tumor suppressor genes guarding the order of the epithelial organization. Studies in Drosophila have exposed genes that encode key regulators of the epithelial apicobasal polarity and which, upon inactivation, cause disorganization of the epithelial layers and promote unscheduled cell proliferation. These polarity regulator/tumor suppressor proteins, which include products of neoplastic tumor suppressor genes (nTSGs), are carefully positioned in polarized epithelial cells to maintain the order of epithelial structures and to impose a restraint on cell proliferation. In this review, we have explored the presence and prevalence of somatic mutations in the human counterparts of Drosophila polarity regulator/tumor suppressor genes across the human cancers. The screen points out LKB1, which is a causal genetic lesion in Peutz-Jeghers cancer syndrome, a gene mutated in certain sporadic cancers and a human homologue of the fly polarity gene par-4. We review the evidence linking Lkb1 protein to polarity regulation in the scope of our recent results suggesting a coupled role for Lkb1 as an architect of organized acinar structures and a suppressor of oncogenic c-Myc. We finally present models to explain how Lkb1-dependent formation of epithelial architecture is coupled to suppression of normal and oncogene-induced proliferation.

Combination of Bifunctional Alkylating Agent and Arsenic Trioxide Synergistically Suppresses the Growth of Drug-Resistant Tumor Cells

Directory of Open Access Journals (Sweden)

Pei-Chih Lee

2010-05-01

Full Text Available Drug resistance is a crucial factor in the failure of cancer chemotherapy. In this study, we explored the effect of combining alkylating agents and arsenic trioxide (ATO on the suppression of tumor cells with inherited or acquired resistance to therapeutic agents. Our results showed that combining ATO and a synthetic derivative of 3a-aza-cyclopenta[a]indenes (BO-1012, a bifunctional alkylating agent causing DNA interstrand cross-links, was more effective in killing human cancer cell lines (H460, H1299, and PC3 than combining ATO and melphalan or thiotepa. We further demonstrated that the combination treatment of H460 cells with BO-1012 and ATO resulted in severe G2/M arrest and apoptosis. In a xenograft mouse model, the combination treatment with BO-1012 and ATO synergistically reduced tumor volumes in nude mice inoculated with H460 cells. Similarly, the combination of BO-1012 and ATO effectively reduced the growth of cisplatin-resistant NTUB1/P human bladder carcinoma cells. Furthermore, the repair of BO-1012-induced DNA interstrand cross-links was significantly inhibited by ATO, and consequently, γH2AX was remarkably increased and formed nuclear foci in H460 cells treated with this drug combination. In addition, Rad51 was activated by translocating and forming foci in nuclei on treatment with BO-1012, whereas its activation was significantly suppressed by ATO. We further revealed that ATO might mediate through the suppression of AKT activity to inactivate Rad51. Taken together, the present study reveals that a combination of bifunctional alkylating agents and ATO may be a rational strategy for treating cancers with inherited or acquired drug resistance.

CD8+ Tumor-Infiltrating T Cells Are Trapped in the Tumor-Dendritic Cell Network

Directory of Open Access Journals (Sweden)

Alexandre Boissonnas

2013-01-01

Full Text Available Chemotherapy enhances the antitumor adaptive immune T cell response, but the immunosuppressive tumor environment often dominates, resulting in cancer relapse. Antigen-presenting cells such as tumor-associated macrophages (TAMs and tumor dendritic cells (TuDCs are the main protagonists of tumor-infiltrating lymphocyte (TIL immuno-suppression. TAMs have been widely investigated and are associated with poor prognosis, but the immuno-suppressive activity of TuDCs is less well understood. We performed two-photon imaging of the tumor tissue to examine the spatiotemporal interactions between TILs and TuDCs after chemotherapy. In a strongly immuno-suppressive murine tumor model, cyclophosphamide-mediated chemotherapy transiently enhanced the antitumor activity of adoptively transferred ovalbumin-specific CD8+ T cell receptor transgenic T cells (OTI but barely affected TuDC compartment within the tumor. Time lapse imaging of living tumor tissue showed that TuDCs are organized as a mesh with dynamic interconnections. Once infiltrated into the tumor parenchyma, OTI T cells make antigen-specific and long-lasting contacts with TuDCs. Extensive analysis of TIL infiltration on histologic section revealed that after chemotherapy the majority of OTI T cells interact with TuDCs and that infiltration is restricted to TuDC-rich areas. We propose that the TuDC network exerts antigen-dependent unproductive retention that trap T cells and limit their antitumor effectiveness.

Styrene maleic acid-encapsulated RL71 micelles suppress tumor growth in a murine xenograft model of triple negative breast cancer

Directory of Open Access Journals (Sweden)

Martey O

2017-10-01

Full Text Available Orleans Martey,1 Mhairi Nimick,1 Sebastien Taurin,1 Vignesh Sundararajan,1 Khaled Greish,2 Rhonda J Rosengren1 1Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand; 2Department of Molecular Medicine, College of Medicine and Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain Abstract: Patients with triple negative breast cancer have a poor prognosis due in part to the lack of targeted therapies. In the search for novel drugs, our laboratory has developed a second-generation curcumin derivative, 3,5-bis(3,4,5-trimethoxybenzylidene-1-methylpiperidine-4-one (RL71, that exhibits potent in vitro cytotoxicity. To improve the clinical potential of this drug, we have encapsulated it in styrene maleic acid (SMA micelles. SMA-RL71 showed improved biodistribution, and drug accumulation in the tumor increased 16-fold compared to control. SMA-RL71 (10 mg/kg, intravenously, two times a week for 2 weeks also significantly suppressed tumor growth compared to control in a xenograft model of triple negative breast cancer. Free RL71 was unable to alter tumor growth. Tumors from SMA-RL71-treated mice showed a decrease in angiogenesis and an increase in apoptosis. The drug treatment also modulated various cell signaling proteins including the epidermal growth factor receptor, with the mechanisms for tumor suppression consistent with previous work with RL71 in vitro. The nanoformulation was also nontoxic as shown by normal levels of plasma markers for liver and kidney injury following weekly administration of SMA-RL71 (10 mg/kg for 90 days. Thus, we report clinical potential following encapsulation of a novel curcumin derivative, RL71, in SMA micelles. Keywords: curcumin derivatives, nanomedicine, EGFR, biodistribution

Tumor-suppressive function of miR-139-5p in esophageal squamous cell carcinoma.

Directory of Open Access Journals (Sweden)

Ran Liu

Full Text Available Recent studies have demonstrated the possible function of miR-139-5p in tumorigenesis. However, the exact mechanism of miR-139-5p in cancer remains unclear. In this study, the association of miR-139-5p expression with esophageal squamous cell carcinoma (ESCC was evaluated in 106 pairs of esophageal cancer and adjacent non-cancerous tissue from ESCC patients. The tumor suppressive features of miR-139-5p were measured by evaluating cell proliferation and cell cycle state, migratory activity and invasion capability, as well as apoptosis. Luciferase reporter assay and Western blot analysis were performed to determine the target gene regulated by miR-139-5p. The mRNA level of NR5A2, the target gene of miR-139-5p, was determined in ESCC patients. Results showed that reduced miR-139-5p level was associated with lymph node metastases of ESCC. MiR-139-5p was investigated to induce cell cycle arrest in the G0/G1 phase and to suppress the invasive capability of esophageal carcinoma cells by targeting the 3'UTR of oncogenic NR5A2. Cyclin E1 and MMP9 were confirmed to participate in cell cycle arrest and invasive suppression induced by NR5A2, respectively. Pearson correlation analysis further confirmed the significantly negative correlation between miR-139-5p and NR5A2 expression. The results suggest that miR-139-5p exerts a growth- and invasiveness-suppressing function in human ESCCs, which demonstrates that miR-139-5p is a potential biomarker for early diagnosis and prognosis and is a therapeutic target for ESCC.

Off and back-on again: a tumor suppressor's tale.

Science.gov (United States)

Acosta, Jonuelle; Wang, Walter; Feldser, David M

2018-06-01

Tumor suppressor genes play critical roles orchestrating anti-cancer programs that are both context dependent and mechanistically diverse. Beyond canonical tumor suppressive programs that control cell division, cell death, and genome stability, unexpected tumor suppressor gene activities that regulate metabolism, immune surveillance, the epigenetic landscape, and others have recently emerged. This diversity underscores the important roles these genes play in maintaining cellular homeostasis to suppress cancer initiation and progression, but also highlights a tremendous challenge in discerning precise context-specific programs of tumor suppression controlled by a given tumor suppressor. Fortunately, the rapid sophistication of genetically engineered mouse models of cancer has begun to shed light on these context-dependent tumor suppressor activities. By using techniques that not only toggle "off" tumor suppressor genes in nascent tumors, but also facilitate the timely restoration of gene function "back-on again" in disease specific contexts, precise mechanisms of tumor suppression can be revealed in an unbiased manner. This review discusses the development and implementation of genetic systems designed to toggle tumor suppressor genes off and back-on again and their potential to uncover the tumor suppressor's tale.

RNAi screening of subtracted transcriptomes reveals tumor suppression by taurine-activated GABAA receptors involved in volume regulation

Science.gov (United States)

van Nierop, Pim; Vormer, Tinke L.; Foijer, Floris; Verheij, Joanne; Lodder, Johannes C.; Andersen, Jesper B.; Mansvelder, Huibert D.; te Riele, Hein

2018-01-01

To identify coding and non-coding suppressor genes of anchorage-independent proliferation by efficient loss-of-function screening, we have developed a method for enzymatic production of low complexity shRNA libraries from subtracted transcriptomes. We produced and screened two LEGO (Low-complexity by Enrichment for Genes shut Off) shRNA libraries that were enriched for shRNA vectors targeting coding and non-coding polyadenylated transcripts that were reduced in transformed Mouse Embryonic Fibroblasts (MEFs). The LEGO shRNA libraries included ~25 shRNA vectors per transcript which limited off-target artifacts. Our method identified 79 coding and non-coding suppressor transcripts. We found that taurine-responsive GABAA receptor subunits, including GABRA5 and GABRB3, were induced during the arrest of non-transformed anchor-deprived MEFs and prevented anchorless proliferation. We show that taurine activates chloride currents through GABAA receptors on MEFs, causing seclusion of cell volume in large membrane protrusions. Volume seclusion from cells by taurine correlated with reduced proliferation and, conversely, suppression of this pathway allowed anchorage-independent proliferation. In human cholangiocarcinomas, we found that several proteins involved in taurine signaling via GABAA receptors were repressed. Low GABRA5 expression typified hyperproliferative tumors, and loss of taurine signaling correlated with reduced patient survival, suggesting this tumor suppressive mechanism operates in vivo. PMID:29787571

Enhanced inflammation and attenuated tumor suppressor pathways are associated with oncogene-induced lung tumors in aged mice

Science.gov (United States)

Aging is often accompanied by a dramatic increase in cancer susceptibility. To gain insights into how aging affects tumor susceptibility, we generated a conditional mouse model in which oncogenic KrasG12D was activated specifically in lungs of young (3-5 months) and old (19-24 months) mice. Activati...

Relaxin suppresses atrial fibrillation in aged rats by reversing fibrosis and upregulating Na+ channels.

Science.gov (United States)

Henry, Brian L; Gabris, Beth; Li, Qiao; Martin, Brian; Giannini, Marianna; Parikh, Ashish; Patel, Divyang; Haney, Jamie; Schwartzman, David S; Shroff, Sanjeev G; Salama, Guy

2016-04-01

Atrial fibrillation (AF) contributes significantly to morbidity and mortality in elderly patients and has been correlated with enhanced age-dependent atrial fibrosis. Reversal of atrial fibrosis has been proposed as therapeutic strategy to suppress AF. To test the ability of relaxin to reverse age-dependent atrial fibrosis and suppress AF. Aged F-344 rats (24 months old) were treated with subcutaneous infusion of vehicle or relaxin (0.4 mg/kg/day) for 2 weeks. Rat hearts were excised, perfused on a Langendorff apparatus, and stained with voltage and Ca(2+) indicator dyes. Optical mapping and programmed electrical stimulation was used to test arrhythmia vulnerability and changes in electrophysiological characteristics. Changes in protein expression and Na(+) current density (INa) were measured by tissue immunofluorescence and whole-cell patch clamp technique. In aged rats, sustained AF was readily induced with a premature pulse (n = 7/8) and relaxin treatment suppressed sustained AF by a premature impulse or burst pacing (n = 1/6) (P atrial action potential conduction velocity and decreased atrial fibrosis. Relaxin treatment increased Nav1.5 expression (n = 6; 36% ± 10%) and decreased total collagen and collagen I (n = 5-6; 55%-66% ± 15%) in aged atria (P atrial INa by 46% ± 4% (n = 12-13/group, P atrial conduction velocity by decreasing atrial fibrosis and increasing INa. These data provide compelling evidence that relaxin may serve as an effective therapy to manage AF in geriatric patients by reversing fibrosis and modulating cardiac ionic currents. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Deoxypodophyllotoxin suppresses tumor vasculature in HUVECs by promoting cytoskeleton remodeling through LKB1-AMPK dependent Rho A activatio.

Science.gov (United States)

Wang, Yurong; Wang, Bin; Guerram, Mounia; Sun, Li; Shi, Wei; Tian, Chongchong; Zhu, Xiong; Jiang, Zhenzhou; Zhang, Luyong

2015-10-06

Angiogenesis plays a critical role in the growth and metastasis of tumors, which makes it an attractive target for anti-tumor drug development. Deoxypodophyllotoxin (DPT), a natural product isolated from Anthriscus sylvestris, inhibits cell proliferation and migration in various cancer cell types. Our previous studies indicate that DPT possesses both anti-angiogenic and vascular-disrupting activities. Although the RhoA/ RhoA kinase (ROCK) signaling pathway is implicated in DPT-stimulated cytoskeleton remodeling and tumor vasculature suppressing, the detailed mechanisms by which DPT mediates these effects are poorly understood. In the current study, we found that DPT promotes cytoskeleton remodeling in human umbilical vein endothelial cells (HUVECs) via stimulation of AMP-activated protein kinase (AMPK) and that this effect is abolished by either treatment with a selective AMPK inhibitor or knockdown. Moreover, the cellular levels of LKB1, a kinase upstream of AMPK, were enhanced following DPT exposure. DPT-induced activation of AMPK in tumor vasculature effect was also verified by transgenic zebrafish (VEGFR2:GFP), Matrigel plug assay, and xenograft model in nude mice. The present findings may lay the groundwork for a novel therapeutic approach in treating cancer.

A stressful microenvironment: opposing effects of the endoplasmic reticulum stress response in the suppression and enhancement of adaptive tumor immunity.

Science.gov (United States)

Rausch, Matthew P; Sertil, Aparna Ranganathan

2015-03-01

The recent clinical success of immunotherapy in the treatment of certain types of cancer has demonstrated the powerful ability of the immune system to control tumor growth, leading to significantly improved patient survival. However, despite these promising results current immunotherapeutic strategies are still limited and have not yet achieved broad acceptance outside the context of metastatic melanoma. The limitations of current immunotherapeutic approaches can be attributed in part to suppressive mechanisms present in the tumor microenvironment that hamper the generation of robust antitumor immune responses thus allowing tumor cells to escape immune-mediated destruction. The endoplasmic reticulum (ER) stress response has recently emerged as a potent regulator of tumor immunity. The ER stress response is an adaptive mechanism that allows tumor cells to survive in the harsh growth conditions inherent to the tumor milieu such as low oxygen (hypoxia), low pH and low levels of glucose. Activation of ER stress can also alter the cancer cell response to therapies. In addition, the ER stress response promotes tumor immune evasion by inducing the production of protumorigenic inflammatory cytokines and impairing tumor antigen presentation. However, the ER stress response can boost antitumor immunity in some situations by enhancing the processing and presentation of tumor antigens and by inducing the release of immunogenic factors from stressed tumor cells. Here, we discuss the dualistic role of the ER stress response in the modulation of tumor immunity and highlight how strategies to either induce or block ER stress can be employed to improve the clinical efficacy of tumor immunotherapy.

Effect of aged garlic extract on immune responses to experimental fibrosarcoma tumor in BALB/c mice.

Science.gov (United States)

Tabari, M Abouhosseini; Ebrahimpour, S

2014-01-01

Aged garlic extract (AGE) has many biological activities including radical scavenging, antioxidative and immunomodulative effects. In this research work, the antitumor and immunomodulatory effects of AGE against fibrosarcoma implanted tumor were studied. WEHI-164 fibrosarcoma cells were implanted subcutaneously on day 0 into the right flank of 40 BALB/c mice at age of 8 weeks. Mice were randomly categorized in two separate groups: First received AGE (100 mg/kg, IP), second group as the control group received phosphate buffered saline. Treatments were carried out 3 times/week. Tumor growth was measured and morbidity was recorded. Subpopulations of CD4+/CD8+ T cells were determined using flow cytometry. WEHI-164 cell specific cytotoxicity of splenocytes and in vitro production of interferon gamma (IFN-γ) and interleukin-4 cytokines were measured. The mice received AGE had significantly longer survival time compared with the control mice. The inhibitory effect on tumor growth was seen in AGE treated mice. The CD4+/CD8+ ratio and in vitro IFN-γ production of splenocytes were significantly increased in AGE group. WEHI-164 specific cytotoxicity of splenocytes from AGE mice was also significantly increased at 25:1 E: T ratio. Administration of AGE resulted in improved immune responses against experimentally implanted fibrosarcoma tumors in BALB/c mice. AGE showed significant effects on inhibition of tumor growth and longevity of survival times.

Suppression of human breast tumors in NOD/SCID mice by CD44 shRNA gene therapy combined with doxorubicin treatment

Directory of Open Access Journals (Sweden)

Pham PV

2012-05-01

Full Text Available Phuc Van Pham1, Ngoc Bich Vu1, Thuy Thanh Duong1, Tam Thanh Nguyen1, Nhung Hai Truong1, Nhan Lu Chinh Phan1, Tue Gia Vuong1, Viet Quoc Pham1, Hoang Minh Nguyen1, Kha The Nguyen1, Nhung Thi Nguyen1, Khue Gia Nguyen1, Lam Tan Khat1, Dong Van Le2, Kiet Dinh Truong1, Ngoc Kim Phan11Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, HCM City, 2Military Medical University, Ha Noi, VietnamBackground: Breast cancer stem cells with a CD44+CD24- phenotype are the origin of breast tumors. Strong CD44 expression in this population indicates its important role in maintaining the stem cell phenotype. Previous studies show that CD44 down-regulation causes CD44+CD24- breast cancer stem cells to differentiate into non-stem cells that are sensitive to antitumor drugs and lose many characteristics of the original cells. In this study, we determined tumor suppression in non-obese severe combined immunodeficiency mice using CD44 shRNA therapy combined with doxorubicin treatment.Methods: Tumor-bearing non-obese severe combined immunodeficiency mice were established by injection of CD44+CD24- cells. To track CD44+CD24- cells, green fluorescence protein was stably transduced using a lentiviral vector prior to injection into mice. The amount of CD44 shRNA lentiviral vector used for transduction was based on CD44 down-regulation by in vitro CD44 shRNA transduction. Mice were treated with direct injection of CD44 shRNA lentiviral vector into tumors followed by doxorubicin administration after 48 hours. The effect was evaluated by changes in the size and weight of tumors compared with that of the control.Results: The combination of CD44 down-regulation and doxorubicin strongly suppressed tumor growth with significant differences in tumor sizes and weights compared with that of CD44 down-regulation or doxorubicin treatment alone. In the combination of CD44 down-regulation and doxorubicin group, the tumor weight was

Down-regulation of HSP40 gene family following OCT4B1 suppression in human tumor cell lines

Directory of Open Access Journals (Sweden)

Mohammad Reza Mirzaei

2016-02-01

Full Text Available Objective(s: The OCT4B1, as one of OCT4 variants, is expressed in cancer cell lines and tissues more than other variants and plays an important role in apoptosis and stress (heat shock protein pathways. The present study was designed to determine the effects of OCT4B1 silencing on expressional profile of HSP40 gene family expression in three different human tumor cell lines. Materials and Methods: The OCT4B1 expression was suppressed by specific siRNA transfection in AGS (gastric adenocarcinoma, 5637 (bladder tumor and U-87MG (brain tumor cell lines employing Lipofectamine reagent. Real-time PCR array technique was employed for RNA qualification. The fold changes were calculated using RT2 Profiler PCR array data analysis software version 3.5. Results: Our results indicated that fifteen genes (from 36 studied genes were down-regulated and two genes (DNAJC11 and DNAJC5B were up-regulated in all three studied tumor cell lines by approximately more than two folds. The result of other studied genes (19 genes showed different expressional pattern (up or down-expression based on tumor cell lines. Conclusion: According to the findings of the present study, we may suggest that there is a direct correlation between OCT4B1 expression in tumor cell lines (and tissues and HSP40 family gene expressions to escape from apoptosis and cancer expansion.

Age and the risk of anaplasia in magnetic resonance-nonenhancing supratentorial cerebral tumors.

Science.gov (United States)

Barker, F G; Chang, S M; Huhn, S L; Davis, R L; Gutin, P H; McDermott, M W; Wilson, C B; Prados, M D

1997-09-01

It is often assumed that a cerebral lesion that is nonenhancing on a magnetic resonance imaging study with gadolinium contrast is a low grade tumor. Some physicians recommend observation rather than biopsy for such lesions. The authors prospectively evaluated the incidence of anaplastic tumor histology in a consecutive series of patients who presented to a neuro-oncology service with a nonenhancing mass of the cerebral hemisphere. During a 5-month period, the authors evaluated 31 patients who had a nonenhancing lesion in the cerebral hemisphere on initial magnetic resonance images. Thirty patients underwent stereotactic biopsy (27%) or open resection (73%). The median patient age was 36 years (range, 6-63 years). There was no mortality or permanent neurologic morbidity from surgery. Twenty-eight patients had pathologic confirmation of diagnosis while their lesions were still nonenhancing. Of these patients, 9 (32%) had Grade 3 lesions (anaplastic astrocytoma or oligoastrocytoma), 13 (43%) had Grade 2 lesions (astrocytoma, oligodendroglioma, or oligoastrocytoma), and 2 (7%) had Grade 1 lesions (dysembryoplastic neuroepithelial tumors). Two additional patients (ages 33 and 59 years) who developed enhancement within their lesions during preoperative periods of observation had glioblastomas at surgery. Logistic regression was used to relate patient age to the risk of anaplasia in a nonenhancing cerebral mass lesion. Older age predicted a significantly higher risk of anaplasia (P = 0.025). The model predicted that nonenhancing cerebral masses in patients older than 44 years were more likely to be anaplastic tumors than low grade tumors. There was no "safe" age below which low grade histology could be confidently assumed. Magnetic resonance-nonenhancing cerebral lesions may be histologically anaplastic, even in young patients. The risk of anaplasia in magnetic resonance-nonenhancing lesions increases significantly with patient age.

Monoclonal antibodies reactive with common tumor antigens on UV-induced tumors also react with hyperplastic UV-irradiated skin

International Nuclear Information System (INIS)

Spellman, C.W.; Beauchamp, D.A.

1986-01-01

Most murine skin tumors induced by ultraviolet light (UVB, 280-340 nm) can be successfully transplanted only into syngeneic hosts that have received subcarcinogenic doses of UVB. The tumor susceptible state is long-lived and mediated by T suppressor cells that control effector responses against common antigens on UV-induced tumors. Because antigen specific suppression arises prior to the appearance of a tumor, questions arise about the source of the original antigen. They have previously reported transplantation studies indicating that UV-irradiated skin is antigenically cross-reactive with UV-induced tumors. They now report on flow cytometry analyses showing that a series of MoAb reactive with common antigens expressed by UV-induced tumors are also reactive on cells from UV-irradiated skin. Various antigens appear at different times in the UV irradiation scheme, and some persist while others are transient. They speculate that the common antigens detected may be the ones to which functional suppression is directed. If true, these results suggest that successful tumors need not escape host defenses to emerge. Rather, tumors may arise and grow progressively if they express antigens that cross-react with specificities to which the host has previously mounted a suppressive response

Precise let-7 expression levels balance organ regeneration against tumor suppression

Science.gov (United States)

Wu, Linwei; Nguyen, Liem H; Zhou, Kejin; de Soysa, T Yvanka; Li, Lin; Miller, Jason B; Tian, Jianmin; Locker, Joseph; Zhang, Shuyuan; Shinoda, Gen; Seligson, Marc T; Zeitels, Lauren R; Acharya, Asha; Wang, Sam C; Mendell, Joshua T; He, Xiaoshun; Nishino, Jinsuke; Morrison, Sean J; Siegwart, Daniel J; Daley, George Q; Shyh-Chang, Ng; Zhu, Hao

2015-01-01

The in vivo roles for even the most intensely studied microRNAs remain poorly defined. Here, analysis of mouse models revealed that let-7, a large and ancient microRNA family, performs tumor suppressive roles at the expense of regeneration. Too little or too much let-7 resulted in compromised protection against cancer or tissue damage, respectively. Modest let-7 overexpression abrogated MYC-driven liver cancer by antagonizing multiple let-7 sensitive oncogenes. However, the same level of overexpression blocked liver regeneration, while let-7 deletion enhanced it, demonstrating that distinct let-7 levels can mediate desirable phenotypes. let-7 dependent regeneration phenotypes resulted from influences on the insulin-PI3K-mTOR pathway. We found that chronic high-dose let-7 overexpression caused liver damage and degeneration, paradoxically leading to tumorigenesis. These dose-dependent roles for let-7 in tissue repair and tumorigenesis rationalize the tight regulation of this microRNA in development, and have important implications for let-7 based therapeutics. DOI: http://dx.doi.org/10.7554/eLife.09431.001 PMID:26445246

Randomized trial of adjuvant ovarian suppression in 926 premenopausal patients with early breast cancer treated with adjuvant chemotherapy.

Science.gov (United States)

Arriagada, R; Lê, M G; Spielmann, M; Mauriac, L; Bonneterre, J; Namer, M; Delozier, T; Hill, C; Tursz, T

2005-03-01

The aim of this multicenter trial was to evaluate the role of ovarian suppression in patients with early breast cancer previously treated with local surgery and adjuvant chemotherapy. Nine hundred and twenty-six premenopausal patients with completely resected breast cancer and either axillary node involvement or histological grade 2 or 3 tumors were randomized after surgery to adjuvant chemotherapy alone (control arm) or adjuvant chemotherapy plus ovarian suppression (ovarian suppression arm). Ovarian suppression was obtained by either radiation-induced ovarian ablation or triptorelin for 3 years. The analyses were performed with Cox models stratified by center. Median follow-up was 9.5 years. Mean age was 43 years. Ninety per cent of patients had histologically proven positive axillary nodes, 63% positive hormonal receptors and 77% had received an anthracycline-based chemotherapy regimen. Ovarian suppression was by radiation-induced ovarian ablation (45% of patients) or with triptorelin (48%). At the time of randomization, all patients had regular menses or their follicle-stimulating hormone and estradiol levels indicated a premenopausal status. The 10-year disease-free survival rates were 49% [95% confidence interval (CI) 44% to 54%] in both arms (P = 0.51). The 10-year overall survival rates were 66% (95% CI 61% to 70%) for the ovarian suppression arm and 68% (95% CI 63% to 73%) for the control arm (P = 0.19). There were no variations in the treatment effect according to age, hormonal receptor status or ovarian suppression modality. However, in patients suppression significantly decreased the risk of recurrence (P = 0.01). The results of this trial, after at least 10 years of follow-up, do not favor the use of ovarian suppression after adjuvant chemotherapy. The potential beneficial effect in younger women with hormono-dependent tumors should be further assessed.

Suppression of tumor growth by a new glycosaminoglycan isolated from the African giant snail Achatina fulica.

Science.gov (United States)

Lee, Yeon Sil; Yang, Hyun Ok; Shin, Kuk Hyun; Choi, Hyung Seok; Jung, Sang Hoon; Kim, Yong Man; Oh, Deok Kun; Linhardt, Robert J; Kim, Yeong Shik

2003-03-28

Acharan sulfate is a new type of glycosaminoglycan from the giant African snail, Achatina fulica. Acharan sulfate, which has a primary repeating disaccharide structure of alpha-D-N-acetylglucosaminyl-2-O-sulfo-alpha-L-iduronic acid, was studied as a potential antitumor agent in both in vivo and in vitro assays. The antiangiogenic activity of acharan sulfate was evaluated in the chorioallantoic membrane assay and by measuring its effect on the proliferation of calf pulmonary artery endothelial cells. In vivo, a matrigel plug assay showed that acharan sulfate suppressed basic fibroblast growth factor (bFGF)-stimulated angiogenesis and lowered the hemoglobin (Hb) content inside the plug. Acharan sulfate was administered s.c. at two doses for 15 days to C57BL/6 mice implanted with murine Lewis lung carcinoma in the back. It was also administered i.p. to ICR mice bearing sarcoma 180 at a dose of 30 mg/kg. Subcutaneous injection of acharan sulfate at doses of 10 and 30 mg/kg decreased tumor weight and tumor volume by 40% without toxicity or resistance. Intraperitoneal injection of acharan sulfate also decreased tumor weight and volume by 40% in sarcoma 180-bearing mice. These results suggest that the antitumor activity of acharan sulfate may be related to the inhibition of angiogenesis.

The PLA2R1-JAK2 pathway upregulates ERRα and its mitochondrial program to exert tumor-suppressive action.

Science.gov (United States)

Griveau, A; Devailly, G; Eberst, L; Navaratnam, N; Le Calvé, B; Ferrand, M; Faull, P; Augert, A; Dante, R; Vanacker, J M; Vindrieux, D; Bernard, D

2016-09-22

Little is known about the biological role of the phospholipase A2 receptor (PLA2R1) transmembrane protein. In recent years, PLA2R1 has been shown to have an important role in regulating tumor-suppressive responses via JAK2 activation, but the underlying mechanisms are largely undeciphered. In this study, we observed that PLA2R1 increases the mitochondrial content, judged by increased levels of numerous mitochondrial proteins, of the mitochondrial structural component cardiolipin, of the mitochondrial DNA content, and of the mitochondrial DNA replication and transcription factor TFAM. This effect of PLA2R1 relies on a transcriptional program controlled by the estrogen-related receptor alpha1 (ERRα) mitochondrial master regulator. Expression of ERRα and of its nucleus-encoded mitochondrial targets is upregulated upon PLA2R1 ectopic expression, and this effect is mediated by JAK2. Conversely, downregulation of PLA2R1 decreases the level of ERRα and of its nucleus-encoded mitochondrial targets. Finally, blocking the ERRα-controlled mitochondrial program largely inhibits the PLA2R1-induced tumor-suppressive response. Together, our data document ERRα and its mitochondrial program as downstream effectors of the PLA2R1-JAK2 pathway leading to oncosuppression.

Human Mut T Homolog 1 (MTH1): a roadblock for the tumor-suppressive effects of oncogenic RAS-induced ROS.

Science.gov (United States)

Rai, Priyamvada

2012-01-01

Oncogenic RAS-induced reactive oxygen species (ROS) trigger barriers to cell transformation and cancer progression through tumor-suppressive responses such as cellular senescence or cell death. We have recently shown that oncogenic RAS-induced DNA damage and attendant premature senescence can be prevented by overexpressing human MutT Homolog 1 (MTH1), the major mammalian detoxifier of the oxidized DNA precursor, 8-oxo-dGTP. Paradoxically, RAS-induced ROS are also able to participate in tumor progression via transformative processes such as mitogenic signaling, the epithelial-mesenchymal transition (EMT), anoikis inhibition, and PI3K/Akt-mediated survival signaling. Here we provide a preliminary insight into the influence of MTH1 levels on the EMT phenotype and Akt activation in RAS-transformed HMLE breast epithelial cells. Within this context, we will discuss the implications of MTH1 upregulation in oncogenic RAS-sustaining cells as a beneficial adaptive change that inhibits ROS-mediated cell senescence and participates in the maintenance of ROS-associated tumor-promoting mechanisms. Accordingly, targeting MTH1 in RAS-transformed tumor cells will not only induce proliferative defects but also potentially enhance therapeutic cytotoxicity by shifting cellular response away from pro-survival mechanisms.

Rodlike Supramolecular Nanoassemblies of Degradable Poly(Aspartic Acid) Derivatives and Hydroxyl-Rich Polycations for Effective Delivery of Versatile Tumor-Suppressive ncRNAs.

Science.gov (United States)

Song, Hai-Qing; Pan, Wenting; Li, Rui-Quan; Yu, Bingran; Liu, Wenjuan; Yang, Ming; Xu, Fu-Jian

2018-03-01

The delivery of tumor-suppressive noncoding RNAs (ncRNAs) including short ncRNAs (i.e., miRNAs) and long ncRNAs (lncRNAs) is put forward to treat tumors. In this work, novel rodlike supramolecular nanoassemblies (CNC @CB[8] @ PGEA) of degradable poly(aspartic acid) (PAsp) derivatives-grafted cellulose nanocrystals (CNCs) and hydroxyl-rich polycations (ethanolamine-functionalized poly(glycidyl methacrylate), PGEA) are proposed via typical cucurbit[8]uril (CB[8])-based host-guest interactions for delivery of different ncRNAs to treat hepatocellular carcinoma (HCC). Spindly CNCs, one kind of natural polysaccharide nanoparticles, possess good biocompatibility and unique physico-chemical properties. PGEA with abundant hydroxyl groups is one promising gene carrier with low cytotoxicity. PAsp can benefit the disassembly and degradability of nanoassemblies within cells. CNC @ CB[8]@PGEA combines the different unique properties of CNC, PGEA, and PAsp. CNC @ CB[8] @ PGEA effectively complexes the expression constructs of miR-101 (plasmid pc3.0-miR-101) and lncRNA MEG3 (plasmid pc3.0-MEG3). CNC @ CB[8] @ PGEA produces much better transfection performances than PGEA-containing assembly units. In addition, the codelivery system of CNC @ CB[8] @ PGEA/(pc3.0-MEG3+pc3.0-miR-101) nanocomplexes demonstrates better efficacy in suppressing HCC than CNC @ CB[8] @ PGEA/pc3.0-MEG3 or CNC @ CB[8] @ PGEA/pc3.0-miR-101 nanocomplexes alone. Such rodlike supramolecular nanoassemblies will provide a promising means to produce efficient delivery vectors of versatile tumor-suppressive nucleic acids. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Transformation Resistance in a Premature Aging Disorder Identifies a Tumor-Protective Function of BRD4

Directory of Open Access Journals (Sweden)

Patricia Fernandez

2014-10-01

Full Text Available Summary: Advanced age and DNA damage accumulation are prominent risk factors for cancer. The premature aging disorder Hutchinson-Gilford progeria syndrome (HGPS provides a unique opportunity for studying the interplay between DNA damage and aging-associated tumor mechanisms, given that HGPS patients do not develop tumors despite elevated levels of DNA damage. Here, we have used HGPS patient cells to identify a protective mechanism to oncogenesis. We find that HGPS cells are resistant to neoplastic transformation. Resistance is mediated by the bromodomain protein BRD4, which exhibits altered genome-wide binding patterns in transformation-resistant cells, leading to inhibition of oncogenic dedifferentiation. BRD4 also inhibits, albeit to a lower extent, the tumorigenic potential of transformed cells from healthy individuals. BRD4-mediated tumor protection is clinically relevant given that a BRD4 gene signature predicts positive clinical outcome in breast and lung cancer. Our results demonstrate a protective function for BRD4 and suggest tissue-specific roles for BRD4 in tumorigenesis. : The premature aging disorder Hutchinson-Gilford progeria syndrome (HGPS provides a unique tool for studying the interplay between DNA damage and aging-associated tumor mechanisms, given that HGPS patients do not develop tumors despite elevated levels of DNA damage. Using a genome-wide RNAi screen, Fernandez et al. now identify the bromodomain protein BRD4 as a mediator of the oncogenic resistance of HGPS cells. This tumor-protective function of BRD4 involves inhibition of oncogenic dedifferentiation and is also active in non-HGPS cells in a tissue-specific manner.

Disrupting Hypoxia-Induced Bicarbonate Transport Acidifies Tumor Cells and Suppresses Tumor Growth.

Science.gov (United States)

McIntyre, Alan; Hulikova, Alzbeta; Ledaki, Ioanna; Snell, Cameron; Singleton, Dean; Steers, Graham; Seden, Peter; Jones, Dylan; Bridges, Esther; Wigfield, Simon; Li, Ji-Liang; Russell, Angela; Swietach, Pawel; Harris, Adrian L

2016-07-01

Tumor hypoxia is associated clinically with therapeutic resistance and poor patient outcomes. One feature of tumor hypoxia is activated expression of carbonic anhydrase IX (CA9), a regulator of pH and tumor growth. In this study, we investigated the hypothesis that impeding the reuptake of bicarbonate produced extracellularly by CA9 could exacerbate the intracellular acidity produced by hypoxic conditions, perhaps compromising cell growth and viability as a result. In 8 of 10 cancer cell lines, we found that hypoxia induced the expression of at least one bicarbonate transporter. The most robust and frequent inductions were of the sodium-driven bicarbonate transporters SLC4A4 and SLC4A9, which rely upon both HIF1α and HIF2α activity for their expression. In cancer cell spheroids, SLC4A4 or SLC4A9 disruption by either genetic or pharmaceutical approaches acidified intracellular pH and reduced cell growth. Furthermore, treatment of spheroids with S0859, a small-molecule inhibitor of sodium-driven bicarbonate transporters, increased apoptosis in the cell lines tested. Finally, RNAi-mediated attenuation of SLC4A9 increased apoptosis in MDA-MB-231 breast cancer spheroids and dramatically reduced growth of MDA-MB-231 breast tumors or U87 gliomas in murine xenografts. Our findings suggest that disrupting pH homeostasis by blocking bicarbonate import might broadly relieve the common resistance of hypoxic tumors to anticancer therapy. Cancer Res; 76(13); 3744-55. ©2016 AACR. ©2016 American Association for Cancer Research.

Inhibition of IL-17A suppresses enhanced-tumor growth in low dose pre-irradiated tumor beds.

Directory of Open Access Journals (Sweden)

Eun-Jung Lee

Full Text Available Ionizing radiation induces modification of the tumor microenvironment such as tumor surrounding region, which is relevant to treatment outcome after radiotherapy. In this study, the effects of pre-irradiated tumor beds on the growth of subsequently implanted tumors were investigated as well as underlying mechanism. The experimental model was set up by irradiating the right thighs of C3H/HeN mice with 5 Gy, followed by the implantation of HCa-I and MIH-2. Both implanted tumors in the pre-irradiated bed showed accelerated-growth compared to the control. Tumor-infiltrated lymphocyte (TIL levels were increased, as well as pro-tumor factors such as IL-6 and transforming growth factor-beta1 (TGF-β1 in the pre-irradiated group. In particular, the role of pro-tumor cytokine interleukin-17A (IL-17A was investigated as a possible target mechanism because IL-6 and TGF-β are key factors in Th17 cells differentiation from naïve T cells. IL-17A expression was increased not only in tumors, but also in CD4+ T cells isolated from the tumor draining lymph nodes. The effect of IL-17A on tumor growth was confirmed by treating tumors with IL-17A antibody, which abolished the acceleration of tumor growth. These results indicate that the upregulation of IL-17A seems to be a key factor for enhancing tumor growth in pre-irradiated tumor beds.

Chemotherapy in conjoint aging-tumor systems: some simple models for addressing coupled aging-cancer dynamics

Directory of Open Access Journals (Sweden)

Witten Tarynn M

2010-06-01

Full Text Available Abstract Background In this paper we consider two approaches to examining the complex dynamics of conjoint aging-cancer cellular systems undergoing chemotherapeutic intervention. In particular, we focus on the effect of cells growing conjointly in a culture plate as a precursor to considering the larger multi-dimensional models of such systems. Tumor cell growth is considered from both the logistic and the Gompertzian case, while normal cell growth of fibroblasts (WI-38 human diploid fibroblasts is considered as logistic only. Results We demonstrate, in a simple approach, how the interdependency of different cell types in a tumor, together with specifications of for treatment, can lead to different evolutionary patterns for normal and tumor cells during a course of therapy. Conclusions These results have significance for understanding appropriate pharmacotherapy for elderly patients who are also undergoing chemotherapy.

Micro-environmental mechanical stress controls tumor spheroid size and morphology by suppressing proliferation and inducing apoptosis in cancer cells.

Directory of Open Access Journals (Sweden)

Gang Cheng

Full Text Available Compressive mechanical stress produced during growth in a confining matrix limits the size of tumor spheroids, but little is known about the dynamics of stress accumulation, how the stress affects cancer cell phenotype, or the molecular pathways involved.We co-embedded single cancer cells with fluorescent micro-beads in agarose gels and, using confocal microscopy, recorded the 3D distribution of micro-beads surrounding growing spheroids. The change in micro-bead density was then converted to strain in the gel, from which we estimated the spatial distribution of compressive stress around the spheroids. We found a strong correlation between the peri-spheroid solid stress distribution and spheroid shape, a result of the suppression of cell proliferation and induction of apoptotic cell death in regions of high mechanical stress. By compressing spheroids consisting of cancer cells overexpressing anti-apoptotic genes, we demonstrate that mechanical stress-induced apoptosis occurs via the mitochondrial pathway.Our results provide detailed, quantitative insight into the role of micro-environmental mechanical stress in tumor spheroid growth dynamics, and suggest how tumors grow in confined locations where the level of solid stress becomes high. An important implication is that apoptosis via the mitochondrial pathway, induced by compressive stress, may be involved in tumor dormancy, in which tumor growth is held in check by a balance of apoptosis and proliferation.

siRNA-mediated Erc gene silencing suppresses tumor growth in Tsc2 mutant renal carcinoma model.

Science.gov (United States)

Imamura, Osamu; Okada, Hiroaki; Takashima, Yuuki; Zhang, Danqing; Kobayashi, Toshiyuki; Hino, Okio

2008-09-18

Silencing of gene expression by small interfering RNAs (siRNAs) is rapidly becoming a powerful tool for genetic analysis and represents a potential strategy for therapeutic product development. However, there are no reports of systemic delivery of siRNAs for stable treatment except short hairpin RNAs (shRNAs). On the other hand, there are many reports of systemic delivery of siRNAs for transient treatment using liposome carriers and others. With regard to shRNAs, a report showed fatality in mice due to oversaturation of cellular microRNA/short hairpin RNA pathways. Therefore, we decided to use original siRNA microspheres instead of shRNA for stable treatment of disease. In this study, we designed rat-specific siRNA sequences for Erc/mesothelin, which is a tumor-specific gene expressed in the Eker (Tsc2 mutant) rat model of hereditary renal cancer and confirmed the efficacy of gene silencing in vitro. Then, by using siRNA microspheres, we found that the suppression of Erc/mesothelin caused growth inhibition of Tsc2 mutant renal carcinoma cells in tumor implantation experiments in mice.

Age and Space Irradiation Modulate Tumor Progression: Implications for Carcinogenesis Risk

Data.gov (United States)

National Aeronautics and Space Administration — Age plays a major role in tumor incidence and is an important consideration when modeling the carcinogenesis process or estimating cancer risks. Epidemiological data...

CO2 bubbling-based 'Nanobomb' System for Targetedly Suppressing Panc-1 Pancreatic Tumor via Low Intensity Ultrasound-activated Inertial Cavitation.

Science.gov (United States)

Zhang, Kun; Xu, Huixiong; Chen, Hangrong; Jia, Xiaoqing; Zheng, Shuguang; Cai, Xiaojun; Wang, Ronghui; Mou, Juan; Zheng, Yuanyi; Shi, Jianlin

2015-01-01

Noninvasive and targeted physical treatment is still desirable especially for those cancerous patients. Herein, we develop a new physical treatment protocol by employing CO2 bubbling-based 'nanobomb' system consisting of low-intensity ultrasound (1.0 W/cm(2)) and a well-constructed pH/temperature dual-responsive CO2 release system. Depending on the temperature elevation caused by exogenous low-intensity therapeutic ultrasound irradiation and the low pH caused by the endogenous acidic-environment around/within tumor, dual-responsive CO2 release system can quickly release CO2 bubbles, and afterwards, the generated CO2 bubbles waves will timely explode before dissolution due to triggering by therapeutic ultrasound waves. Related bio-effects (e.g., cavitation, mechanical, shock waves, etc) caused by CO2 bubbles' explosion effectively induce instant necrosis of panc-1 cells and blood vessel destruction within panc-1 tumor, and consequently inhibit the growth of panc-1 solid tumor, simultaneously minimizing the side effects to normal organs. This new physiotherapy employing CO2 bubbling-based 'nanobomb' system promises significant potentials in targetedly suppressing tumors, especially for those highly deadly cancers.

A low carbohydrate, high protein diet suppresses intratumoral androgen synthesis and slows castration-resistant prostate tumor growth in mice.

Science.gov (United States)

Fokidis, H Bobby; Yieng Chin, Mei; Ho, Victor W; Adomat, Hans H; Soma, Kiran K; Fazli, Ladan; Nip, Ka Mun; Cox, Michael; Krystal, Gerald; Zoubeidi, Amina; Tomlinson Guns, Emma S

2015-06-01

likely to be mechanistic drivers behind the observed tumor growth suppression. Copyright © 2015 Elsevier Ltd. All rights reserved.

EGCG Inhibits Proliferation, Invasiveness and Tumor Growth by Up-Regulation of Adhesion Molecules, Suppression of Gelatinases Activity, and Induction of Apoptosis in Nasopharyngeal Carcinoma Cells

Directory of Open Access Journals (Sweden)

Chih-Yeu Fang

2015-01-01

Full Text Available (−-Epigallocatechin-3-gallate (EGCG, a major green tea polyphenol, has been shown to inhibit the proliferation of a variety of tumor cells. Epidemiological studies have shown that drinking green tea can reduce the incidence of nasopharyngeal carcinoma (NPC, yet the underlying mechanism is not well understood. In this study, the inhibitory effect of EGCG was tested on a set of Epstein Barr virus-negative and -positive NPC cell lines. Treatment with EGCG inhibited the proliferation of NPC cells but did not affect the growth of a non-malignant nasopharyngeal cell line, NP460hTert. Moreover, EGCG treated cells had reduced migration and invasive properties. The expression of the cell adhesion molecules E-cadherin and β-catenin was found to be up-regulated by EGCG treatment, while the down-regulation of matrix metalloproteinases (MMP-2 and MMP-9 were found to be mediated by suppression of extracellular signal-regulated kinase (ERK phosphorylation and AP-1 and Sp1 transactivation. Spheroid formation by NPC cells in suspension was significantly inhibited by EGCG. Oral administration of EGCG was capable of suppressing tumor growth in xenografted mice bearing NPC tumors. Treatment with EGCG was found to elevate the expression of p53 and p21, and eventually led to apoptosis of NPC cells via caspase 3 activation. The nuclear translocation of NF-κB and β-catenin was also suppressed by EGCG treatment. These results indicate that EGCG can inhibit the proliferation and invasiveness, and induce apoptosis, of NPC cells, making it a promising agent for chemoprevention or adjuvant therapy of NPC.

Trehalose Liposomes Suppress the Growth of Tumors on Human Lung Carcinoma-bearing Mice by Induction of Apoptosis In Vivo.

Science.gov (United States)

Ichihara, Hideaki; Kuwabara, Keiji; Matsumoto, Yoko

2017-11-01

Previous evidence demonstrates that trehalose liposomes (DMTreC14) composed of L-α-dimyristoylphosphatidylcholine (DMPC) and α-D-glycopyranosyl-α-D-glucopyranoside monomyristate (TreC14) inhibit proliferation and invasion on lung carcinoma (A549 cells) in vitro. Here, we aimed to investigate suppressive effects of DMTreC14 on the growth of tumor on human lung carcinoma bearing mice. DMTreC14 composed of 30 mol% DMPC and 70 mol% TreC14 were prepared by the sonication method. Anti-tumor activities of DMTreC14 using the subcutaneous and orthotopic graft-bearing mice of A549 cells were investigated in vivo. The remarkable reduction of volume and weight in subcutaneous tumors on subcutaneous lung carcinoma-bearing mice topically administrated with DMTreC14 were obtained. Apoptotic-positive cells in the subcutaneous tumor slice of subcutaneous lung carcinoma-bearing mice topically administrated with DMTreC14 were observed using TUNEL staining. Lung weights on the orthotopic graft-bearing mice of lung carcinoma intravenously administrated with DMTreC14 were markedly decreased compared to those of the control group. Remarkable decrease in dimensions of tumor area of lung on the orthotopic graft-bearing mice of lung carcinoma intravenously administrated with DMTreC14 was obtained in histological analysis using the hematoxylin and eosin staining. Remarkably high anti-tumor activities of DMTreC14 for the subcutaneous and orthotopic graft-bearing mice of lung carcinoma accompanied with apoptosis were revealed for the first time in vivo. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Selinexor (KPT-330) Induces Tumor Suppression through Nuclear Sequestration of IκB and Downregulation of Survivin.

Science.gov (United States)

Nair, Jayasree S; Musi, Elgilda; Schwartz, Gary K

2017-08-01

Purpose: Selinexor, a small molecule that inhibits nuclear export protein XPO1, has demonstrated efficacy in solid tumors and hematologic malignancies with the evidence of clinical activity in sarcoma as a single agent. Treatment options available are very few, and hence the need to identify novel targets and strategic therapies is of utmost importance. Experimental Design: The mechanistic effects of selinexor in sarcomas as a monotherapy and in combination with proteasome inhibitor, carfilzomib, across a panel of cell lines in vitro and few in xenograft mouse models were investigated. Results: Selinexor induced IκB nuclear localization as a single agent, and the effect was enhanced by stabilization of IκB when pretreated with the proteasome inhibitor carfilzomib. This stabilization and retention of IκB in the nucleus resulted in inhibition of NFκB and transcriptional suppression of the critical antiapoptotic protein, survivin. Treatment of carfilzomib followed by selinexor caused selinexor-sensitive and selinexor-resistant cell lines to be more sensitive to selinexor as determined by an increase in apoptosis. This was successfully demonstrated in the MPNST xenograft model with enhanced tumor suppression. Conclusions: The subcellular distributions of IκB and NFκB are indicative of carcinogenesis. Inhibition of XPO1 results in intranuclear retention of IκB, which inhibits NFκB and thereby provides a novel mechanism for drug therapy in sarcoma. This effect can be further enhanced in relatively selinexor-resistant sarcoma cell lines by pretreatment with the proteasome inhibitor carfilzomib. Because of these results, a human clinical trial with selinexor in combination with a proteasome inhibitor is planned for the treatment of sarcoma. Clin Cancer Res; 23(15); 4301-11. ©2017 AACR . ©2017 American Association for Cancer Research.

Star formation suppression and bar ages in nearby barred galaxies

Science.gov (United States)

James, P. A.; Percival, S. M.

2018-03-01

We present new spectroscopic data for 21 barred spiral galaxies, which we use to explore the effect of bars on disc star formation, and to place constraints on the characteristic lifetimes of bar episodes. The analysis centres on regions of heavily suppressed star formation activity, which we term `star formation deserts'. Long-slit optical spectroscopy is used to determine H β absorption strengths in these desert regions, and comparisons with theoretical stellar population models are used to determine the time since the last significant star formation activity, and hence the ages of the bars. We find typical ages of ˜1 Gyr, but with a broad range, much larger than would be expected from measurement errors alone, extending from ˜0.25 to >4 Gyr. Low-level residual star formation, or mixing of stars from outside the `desert' regions, could result in a doubling of these age estimates. The relatively young ages of the underlying populations coupled with the strong limits on the current star formation rule out a gradual exponential decline in activity, and hence support our assumption of an abrupt truncation event.

Chrysin inhibits tumor promoter-induced MMP-9 expression by blocking AP-1 via suppression of ERK and JNK pathways in gastric cancer cells.

Directory of Open Access Journals (Sweden)

Yong Xia

Full Text Available Cell invasion is a crucial mechanism of cancer metastasis and malignancy. Matrix metalloproteinase-9 (MMP-9 is an important proteolytic enzyme involved in the cancer cell invasion process. High expression levels of MMP-9 in gastric cancer positively correlate with tumor aggressiveness and have a significant negative correlation with patients' survival times. Recently, mechanisms suppressing MMP-9 by phytochemicals have become increasingly investigated. Chrysin, a naturally occurring chemical in plants, has been reported to suppress tumor metastasis. However, the effects of chrysin on MMP-9 expression in gastric cancer have not been well studied. In the present study, we tested the effects of chrysin on MMP-9 expression in gastric cancer cells, and determined its underlying mechanism. We examined the effects of chrysin on MMP-9 expression and activity via RT-PCR, zymography, promoter study, and western blotting in human gastric cancer AGS cells. Chrysin inhibited phorbol-12-myristate 13-acetate (PMA-induced MMP-9 expression in a dose-dependent manner. Using AP-1 decoy oligodeoxynucleotides, we confirmed that AP-1 was the crucial transcriptional factor for MMP-9 expression. Chrysin blocked AP-1 via suppression of the phosphorylation of c-Jun and c-Fos through blocking the JNK1/2 and ERK1/2 pathways. Furthermore, AGS cells pretreated with PMA showed markedly enhanced invasiveness, which was partially abrogated by chrysin and MMP-9 antibody. Our results suggest that chrysin may exert at least part of its anticancer effect by controlling MMP-9 expression through suppression of AP-1 activity via a block of the JNK1/2 and ERK1/2 signaling pathways in gastric cancer AGS cells.

Cancer-Associated Fibroblasts from lung tumors maintain their immuno-suppressive abilities after high-dose irradiation

Directory of Open Access Journals (Sweden)

Laia eGorchs

2015-05-01

Full Text Available Accumulating evidence supports the notion that high-dose (>5 Gy radiotherapy (RT regimens are triggering stronger pro-immunogenic effects than standard low-dose (2 Gy regimens. However, the effects of RT on certain immunoregulatory elements in tumors remain unexplored. In this study we have investigated the effects of high-dose irradiation (HD-RT on the immunomodulating functions of cancer-associated fibroblasts (CAFs. Primary CAF cultures were established from lung cancer specimens derived from patients diagnosed for non-small cell lung cancer. Irradiated and non-irradiated CAFs were examined for immunomodulation in experiments with peripheral blood mononuclear cells from random, healthy donors. Regulation of lymphocytes behavior was checked by lymphocyte proliferation assays, lymphocyte migration assays and T-cell cytokine production. Additionally, CAF-secreted immuno-regulatory factors were studied by multiplex protein arrays, ELISAs and by LC-MS/MS proteomics. In all functional assays we observed a powerful immuno-suppressive effect exerted by CAF-conditioned medium on activated T-cells (p>0,001, and this effect was sustained after a single radiation dose of 18 Gy. Relevant immuno-suppressive molecules such as prostaglandin E2, interleukin-6 and -10, or transforming growth factor-β were found in CAF conditioned medium, but their secretion was unchanged after irradiation. Finally, immunogenic cell death responses in CAFs were studied by exploring the release of high motility group box-1 and ATP. Both alarmins remained undetectable before and after irradiation. In conclusion, CAFs play a powerful immuno-suppressive effect over activated T-cells, and this effect remains unchanged after HD-RT. Importantly, CAFs do not switch on immunogenic cell death responses after exposure to HD-RT.

MRI diagnosis of embryonal tumors in the spinal canal

International Nuclear Information System (INIS)

Sun Jilin; Zhang Xinchuan; Zhang Huaning; Liu Lianxiang; Wu Yujin

1997-01-01

To evaluate MRI diagnostic value of the embryonal tumors in the spinal canal. Materials and methods: The MRI appearances of 15 cases of histologically confirmed embryonal tumors in the spinal canal were analyzed. (1) Lipoma (3 cases) had characteristic MRI appearance, demonstrating high signal intensity on T 1 WI, and moderately high signal on T 2 WI. High signal intensity of the lipoma was turned into low signal intensity by fat suppression technique. (2) Dermoids (2 cases) and epidermoid (7 cases) exhibiting low or iso-low signal on T 1 WI and high or iso-high signal on T 2 WI. All had an iso-intense capsule on T 1 WI. However, the two tumors could not be distinguished from each other. (3) Teratoma (3 cases) appeared as a mass of inhomo-generous signals in the spinal canal including soft tissue, fatty tissue and calcification within the same tumor. The diagnosis of embryonal tumors in the spinal canal mainly depend on their MRI appearances, specific tumor location and patient's age

The “Trojan Horse” Approach to Tumor Immunotherapy: Targeting the Tumor Microenvironment

Directory of Open Access Journals (Sweden)

Delia Nelson

2014-01-01

Full Text Available Most anticancer therapies including immunotherapies are given systemically; yet therapies given directly into tumors may be more effective, particularly those that overcome natural suppressive factors in the tumor microenvironment. The “Trojan Horse” approach of intratumoural delivery aims to promote immune-mediated destruction by inducing microenvironmental changes within the tumour at the same time as avoiding the systemic toxicity that is often associated with more “full frontal” treatments such as transfer of large numbers of laboratory-expanded tumor-specific cytotoxic T lymphocytes or large intravenous doses of cytokine. Numerous studies have demonstrated that intratumoural therapy has the capacity to minimizing local suppression, inducing sufficient “dangerous” tumor cell death to cross-prime strong immune responses, and rending tumor blood vessels amenable to immune cell traffic to induce effector cell changes in secondary lymphoid organs. However, the key to its success is the design of a sound rational approach based on evidence. There is compelling preclinical data for local immunotherapy approaches in tumor immunology. This review summarises how immune events within a tumour can be modified by local approaches, how this can affect systemic antitumor immunity such that distal sites are attacked, and what approaches have been proven most successful so far in animals and patients.

Recombinant tumor necrosis factor alpha inhibits growth of methylcholanthrene-induced sarcoma and enhances natural killer activity of tumor-infiltrating lymphocytes in aging rats

International Nuclear Information System (INIS)

Ziolkowska, Maria; Nowak Joanna, J.; Janiak, Marek; Ryzewska, Alicja

1994-01-01

The effect of recombinant human tumor necrosis factors alpha (rHuTNF-α) on the growth of immunogenic, methylcholanthrene-induced sarcoma (MC-Sa) and natural killer (NK) cell activity of tumor-infiltrating lymphocytes (TIL) in adult and aging rats was investigated. In both groups of animals the growth of transplantable MC-Sa was markedly and similarly inhibited by multiple intratumoral (i.t.) injections of rHuTF-α. This effect was accompanied by stimulation of NK activity of tumor-infiltrating lymphocytes in adult as well as in aging rats. Studies ''in vitro'' demonstrated additionally that rHuTNF-α was a potent stimulator of NK but not of ADCC (antibody-dependent cellular cytotoxicity) activity of spleen lymphocytes from healthy animals. Our results indicate that the antitumor effect of TNF-α is comparable in adult and in aging rats bearing immunogenic MC-Sa. The inhibition of MC-Sa growth may be attributed not only to the TNF-α-induced necrosis of the neoplastic tissue but also to the ''in vivo'' stimulatory effect of this cytokine upon the NK-type function of lymphocytes infiltrating the tumor mass. (author). 31 refs, 5 figs, 2 tabs

Rapamycin suppresses brain aging in senescence-accelerated OXYS rats.

Science.gov (United States)

Kolosova, Nataliya G; Vitovtov, Anton O; Muraleva, Natalia A; Akulov, Andrey E; Stefanova, Natalia A; Blagosklonny, Mikhail V

2013-06-01

Cellular and organismal aging are driven in part by the MTOR (mechanistic target of rapamycin) pathway and rapamycin extends life span inC elegans, Drosophila and mice. Herein, we investigated effects of rapamycin on brain aging in OXYS rats. Previously we found, in OXYS rats, an early development of age-associated pathological phenotypes similar to several geriatric disorders in humans, including cerebral dysfunctions. Behavioral alterations as well as learning and memory deficits develop by 3 months. Here we show that rapamycin treatment (0.1 or 0.5 mg/kg as a food mixture daily from the age of 1.5 to 3.5 months) decreased anxiety and improved locomotor and exploratory behavior in OXYS rats. In untreated OXYS rats, MRI revealed an increase of the area of hippocampus, substantial hydrocephalus and 2-fold increased area of the lateral ventricles. Rapamycin treatment prevented these abnormalities, erasing the difference between OXYS and Wister rats (used as control). All untreated OXYS rats showed signs of neurodegeneration, manifested by loci of demyelination. Rapamycin decreased the percentage of animals with demyelination and the number of loci. Levels of Tau and phospho-Tau (T181) were increased in OXYS rats (compared with Wistar). Rapamycin significantly decreased Tau and inhibited its phosphorylation in the hippocampus of OXYS and Wistar rats. Importantly, rapamycin treatment caused a compensatory increase in levels of S6 and correspondingly levels of phospo-S6 in the frontal cortex, indicating that some downstream events were compensatory preserved, explaining the lack of toxicity. We conclude that rapamycin in low chronic doses can suppress brain aging.

Phosphorylation of the Mdm2 oncoprotein by the c-Abl tyrosine kinase regulates p53 tumor suppression and the radiosensitivity of mice.

Science.gov (United States)

Carr, Michael I; Roderick, Justine E; Zhang, Hong; Woda, Bruce A; Kelliher, Michelle A; Jones, Stephen N

2016-12-27

The p53 tumor suppressor acts as a guardian of the genome by preventing the propagation of DNA damage-induced breaks and mutations to subsequent generations of cells. We have previously shown that phosphorylation of the Mdm2 oncoprotein at Ser394 by the ATM kinase is required for robust p53 stabilization and activation in cells treated with ionizing radiation, and that loss of Mdm2 Ser394 phosphorylation leads to spontaneous tumorigenesis and radioresistance in Mdm2 S394A mice. Previous in vitro data indicate that the c-Abl kinase phosphorylates Mdm2 at the neighboring residue (Tyr393) in response to DNA damage to regulate p53-dependent apoptosis. In this present study, we have generated an Mdm2 mutant mouse (Mdm2 Y393F ) to determine whether c-Abl phosphorylation of Mdm2 regulates the p53-mediated DNA damage response or p53 tumor suppression in vivo. The Mdm2 Y393F mice develop accelerated spontaneous and oncogene-induced tumors, yet display no defects in p53 stabilization and activity following acute genotoxic stress. Although apoptosis is unaltered in these mice, they recover more rapidly from radiation-induced bone marrow ablation and are more resistant to whole-body radiation-induced lethality. These data reveal an in vivo role for c-Abl phosphorylation of Mdm2 in regulation of p53 tumor suppression and bone marrow failure. However, c-Abl phosphorylation of Mdm2 Tyr393 appears to play a lesser role in governing Mdm2-p53 signaling than ATM phosphorylation of Mdm2 Ser394. Furthermore, the effects of these phosphorylation events on p53 regulation are not additive, as Mdm2 Y393F/S394A mice and Mdm2 S394A mice display similar phenotypes.

Prolonged oxidative stress down-regulates Early B cell factor 1 with inhibition of its tumor suppressive function against cholangiocarcinoma genesis

Directory of Open Access Journals (Sweden)

Napat Armartmuntree

2018-04-01

Full Text Available Early B cell factor 1 (EBF1 is a transcription factor involved in the differentiation of several stem cell lineages and it is a negative regulator of estrogen receptors. EBF1 is down-regulated in many tumors, and is believed to play suppressive roles in cancer promotion and progression. However, the functional roles of EBF1 in carcinogenesis are unclear. Liver fluke-infection-associated cholangiocarcinoma (CCA is an oxidative stress-driven cancer of bile duct epithelium. In this study, we investigated EBF1 expression in tissues from CCA patients, CCA cell lines (KKU-213, KKU-214 and KKU-156, cholangiocyte (MMNK1 and its oxidative stress-resistant (ox-MMNK1-L cell lines. The formation of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG was used as an oxidative stress marker. Our results revealed that EBF1 expression was suppressed in cancer cells compared with the individual normal bile duct cells at tumor adjacent areas of CCA tissues. CCA patients with low EBF1 expression and high formation of 8-oxodG were shown to correlate with poor survival. Moreover, EBF1 was suppressed in the oxidative stress-resistant cell line and all of CCA cell lines compared to the cholangiocyte cell line. This suggests that prolonged oxidative stress suppressed EBF1 expression and the reduced EBF1 level may facilitate CCA genesis. To elucidate the significance of EBF1 suppression in CCA genesis, EBF1 expression of the MMNK1 cell line was down-regulated by siRNA technique, and its effects on stem cell properties (CD133 and Oct3/4 expressions, tumorigenic properties (cell proliferation, wound healing and cell migration, estrogen responsive gene (TFF1, estrogen-stimulated wound healing, and cell migration were examined. The results showed that CD133, Oct3/4 and TFF1 expression levels, wound healing, and cell migration of EBF1 knockdown-MMNK1 cells were significantly increased. Also, cell migration of EBF1-knockdown cells was significantly enhanced after 17�

Systemic depletion of L-cyst(e)ine with cyst(e)inase increases reactive oxygen species and suppresses tumor growth.

Science.gov (United States)

Cramer, Shira L; Saha, Achinto; Liu, Jinyun; Tadi, Surendar; Tiziani, Stefano; Yan, Wupeng; Triplett, Kendra; Lamb, Candice; Alters, Susan E; Rowlinson, Scott; Zhang, Yan Jessie; Keating, Michael J; Huang, Peng; DiGiovanni, John; Georgiou, George; Stone, Everett

2017-01-01

Cancer cells experience higher oxidative stress from reactive oxygen species (ROS) than do non-malignant cells because of genetic alterations and abnormal growth; as a result, maintenance of the antioxidant glutathione (GSH) is essential for their survival and proliferation. Under conditions of elevated ROS, endogenous L-cysteine (L-Cys) production is insufficient for GSH synthesis. This necessitates uptake of L-Cys that is predominantly in its disulfide form, L-cystine (CSSC), via the xCT(-) transporter. We show that administration of an engineered and pharmacologically optimized human cyst(e)inase enzyme mediates sustained depletion of the extracellular L-Cys and CSSC pool in mice and non-human primates. Treatment with this enzyme selectively causes cell cycle arrest and death in cancer cells due to depletion of intracellular GSH and ensuing elevated ROS; yet this treatment results in no apparent toxicities in mice even after months of continuous treatment. Cyst(e)inase suppressed the growth of prostate carcinoma allografts, reduced tumor growth in both prostate and breast cancer xenografts and doubled the median survival time of TCL1-Tg:p53 -/- mice, which develop disease resembling human chronic lymphocytic leukemia. It was observed that enzyme-mediated depletion of the serum L-Cys and CSSC pool suppresses the growth of multiple tumors, yet is very well tolerated for prolonged periods, suggesting that cyst(e)inase represents a safe and effective therapeutic modality for inactivating antioxidant cellular responses in a wide range of malignancies.

Kaempferol suppresses bladder cancer tumor growth by inhibiting cell proliferation and inducing apoptosis.

Science.gov (United States)

Dang, Qiang; Song, Wenbin; Xu, Defeng; Ma, Yanmin; Li, Feng; Zeng, Jin; Zhu, Guodong; Wang, Xinyang; Chang, Luke S; He, Dalin; Li, Lei

2015-09-01

The effects of the flavonoid compound, kaempferol, which is an inhibitor of cancer cell proliferation and an inducer of cell apoptosis have been shown in various cancers, including lung, pancreatic, and ovarian, but its effect has never been studied in bladder cancer. Here, we investigated the effects of kaempferol on bladder cancer using multiple in vitro cell lines and in vivo mice studies. The MTT assay results on various bladder cancer cell lines showed that kaempferol enhanced bladder cancer cell cytotoxicity. In contrast, when analyzed by the flow cytometric analysis, DNA ladder experiment, and TUNEL assay, kaempferol significantly was shown to induce apoptosis and cell cycle arrest. These in vitro results were confirmed in in vivo mice studies using subcutaneous xenografted mouse models. Consistent with the in vitro results, we found that treating mice with kaempferol significant suppression in tumor growth compared to the control group mice. Tumor tissue staining results showed decreased expressions of the growth related markers, yet increased expressions in apoptosis markers in the kaempferol treated group mice tissues compared to the control group mice. In addition, our in vitro and in vivo data showed kaempferol can also inhibit bladder cancer invasion and metastasis. Further mechanism dissection studies showed that significant down-regulation of the c-Met/p38 signaling pathway is responsible for the kaempferol mediated cell proliferation inhibition. All these findings suggest kaempferol might be an effective and novel chemotherapeutic drug to apply for the future therapeutic agent to combat bladder cancer. © 2014 Wiley Periodicals, Inc.

Cellular senescence and organismal aging.

Science.gov (United States)

Jeyapalan, Jessie C; Sedivy, John M

2008-01-01

Cellular senescence, first observed and defined using in vitro cell culture studies, is an irreversible cell cycle arrest which can be triggered by a variety of factors. Emerging evidence suggests that cellular senescence acts as an in vivo tumor suppression mechanism by limiting aberrant proliferation. It has also been postulated that cellular senescence can occur independently of cancer and contribute to the physiological processes of normal organismal aging. Recent data have demonstrated the in vivo accumulation of senescent cells with advancing age. Some characteristics of senescent cells, such as the ability to modify their extracellular environment, could play a role in aging and age-related pathology. In this review, we examine current evidence that links cellular senescence and organismal aging.

Aging and insulin signaling differentially control normal and tumorous germline stem cells.

Science.gov (United States)

Kao, Shih-Han; Tseng, Chen-Yuan; Wan, Chih-Ling; Su, Yu-Han; Hsieh, Chang-Che; Pi, Haiwei; Hsu, Hwei-Jan

2015-02-01

Aging influences stem cells, but the processes involved remain unclear. Insulin signaling, which controls cellular nutrient sensing and organismal aging, regulates the G2 phase of Drosophila female germ line stem cell (GSC) division cycle in response to diet; furthermore, this signaling pathway is attenuated with age. The role of insulin signaling in GSCs as organisms age, however, is also unclear. Here, we report that aging results in the accumulation of tumorous GSCs, accompanied by a decline in GSC number and proliferation rate. Intriguingly, GSC loss with age is hastened by either accelerating (through eliminating expression of Myt1, a cell cycle inhibitory regulator) or delaying (through mutation of insulin receptor (dinR) GSC division, implying that disrupted cell cycle progression and insulin signaling contribute to age-dependent GSC loss. As flies age, DNA damage accumulates in GSCs, and the S phase of the GSC cell cycle is prolonged. In addition, GSC tumors (which escape the normal stem cell regulatory microenvironment, known as the niche) still respond to aging in a similar manner to normal GSCs, suggesting that niche signals are not required for GSCs to sense or respond to aging. Finally, we show that GSCs from mated and unmated females behave similarly, indicating that female GSC-male communication does not affect GSCs with age. Our results indicate the differential effects of aging and diet mediated by insulin signaling on the stem cell division cycle, highlight the complexity of the regulation of stem cell aging, and describe a link between ovarian cancer and aging. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Immunotherapy: Shifting the Balance of Cell-Mediated Immunity and Suppression in Human Prostate Cancer

Energy Technology Data Exchange (ETDEWEB)

Tucker, Jo A.; Jochems, Caroline [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Gulley, James L. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Schlom, Jeffrey, E-mail: js141c@nih.gov; Tsang, Kwong Y. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

2012-12-11

Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies.

Immunotherapy: Shifting the Balance of Cell-Mediated Immunity and Suppression in Human Prostate Cancer

International Nuclear Information System (INIS)

Tucker, Jo A.; Jochems, Caroline; Gulley, James L.; Schlom, Jeffrey; Tsang, Kwong Y.

2012-01-01

Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies

Methanol Extract of Polyopes lancifolius Suppresses Tumor ...

African Journals Online (AJOL)

Tumor Necrosis Factor-α-Induced Matrix ... 614-054,4Department of Biomaterial Control (BK21 program) and Blue-Bio Industry Regional Innovation Center,. Dongeui ..... Molecules 2008; 13: ... pancreatic ductal carcinoma is associated with.

Withaferin A Suppresses Liver Tumor Growth in a Nude Mouse ...

African Journals Online (AJOL)

Purpose: To investigate the effect of withaferin A on tumor growth and metastasis in liver in a nude mouse model. Methods: Withaferin A was injected through a portal vein to the orthotopic liver tumor in a nude mice model. Xenogen in vivo imaging system was used to monitor tumor growth and metastasis. The effect of ...

CS2164, a novel multi-target inhibitor against tumor angiogenesis, mitosis and chronic inflammation with anti-tumor potency.

Science.gov (United States)

Zhou, You; Shan, Song; Li, Zhi-Bin; Xin, Li-Jun; Pan, De-Si; Yang, Qian-Jiao; Liu, Ying-Ping; Yue, Xu-Peng; Liu, Xiao-Rong; Gao, Ji-Zhou; Zhang, Jin-Wen; Ning, Zhi-Qiang; Lu, Xian-Ping

2017-03-01

Although inhibitors targeting tumor angiogenic pathway have provided improvement for clinical treatment in patients with various solid tumors, the still very limited anti-cancer efficacy and acquired drug resistance demand new agents that may offer better clinical benefits. In the effort to find a small molecule potentially targeting several key pathways for tumor development, we designed, discovered and evaluated a novel multi-kinase inhibitor, CS2164. CS2164 inhibited the angiogenesis-related kinases (VEGFR2, VEGFR1, VEGFR3, PDGFRα and c-Kit), mitosis-related kinase Aurora B and chronic inflammation-related kinase CSF-1R in a high potency manner with the IC 50 at a single-digit nanomolar range. Consequently, CS2164 displayed anti-angiogenic activities through suppression of VEGFR/PDGFR phosphorylation, inhibition of ligand-dependent cell proliferation and capillary tube formation, and prevention of vasculature formation in tumor tissues. CS2164 also showed induction of G2/M cell cycle arrest and suppression of cell proliferation in tumor tissues through the inhibition of Aurora B-mediated H3 phosphorylation. Furthermore, CS2164 demonstrated the inhibitory effect on CSF-1R phosphorylation that led to the suppression of ligand-stimulated monocyte-to-macrophage differentiation and reduced CSF-1R + cells in tumor tissues. The in vivo animal efficacy studies revealed that CS2164 induced remarkable regression or complete inhibition of tumor growth at well-tolerated oral doses in several human tumor xenograft models. Collectively, these results indicate that CS2164 is a highly selective multi-kinase inhibitor with potent anti-tumor activities against tumor angiogenesis, mitosis and chronic inflammation, which may provide the rationale for further clinical assessment of CS2164 as a therapeutic agent in the treatment of cancer. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Targeting of GIT1 by miR-149* in breast cancer suppresses cell proliferation and metastasis in vitro and tumor growth in vivo

Directory of Open Access Journals (Sweden)

Dong Y

2017-12-01

the tumor growth, while restored GIT1 accelerated the tumor growth in nude mice after 35 days of tumor xenograft. Collectively, these findings concluded that miR-149* might exert a tumor suppressive role in breast cancer by targeting GIT1. Keywords: microRNA 149*, miR-149*, G protein-coupled receptor kinase interacting protein 1, GIT1, tumor suppressive role, breast cancer

L-Asparaginase delivered by Salmonella typhimurium suppresses solid tumors

Directory of Open Access Journals (Sweden)

Kwangsoo Kim

Full Text Available Bacteria can be engineered to deliver anticancer proteins to tumors via a controlled expression system that maximizes the concentration of the therapeutic agent in the tumor. L-asparaginase (L-ASNase, which primarily converts asparagine to aspartate, is an anticancer protein used to treat acute lymphoblastic leukemia. In this study, Salmonellae were engineered to express L-ASNase selectively within tumor tissues using the inducible araBAD promoter system of Escherichia coli. Antitumor efficacy of the engineered bacteria was demonstrated in vivo in solid malignancies. This result demonstrates the merit of bacteria as cancer drug delivery vehicles to administer cancer-starving proteins such as L-ASNase to be effective selectively within the microenvironment of cancer tissue.

More than meets the eye:age differences in the capture and suppression of oculomotor action

Directory of Open Access Journals (Sweden)

K. Richard eRidderinkhof

2011-10-01

Full Text Available Salient visual stimuli capture attention and trigger an eye-movement towards its location reflexively, regardless of an observer’s intentions. Here we investigate the effect of aging 1 on the extent to which salient yet task-irrelevant stimuli capture saccades, and 2 on the ability to selectively suppress such oculomotor responses. Young and older adults were asked to direct their eyes to a target appearing in a stimulus array. Analysis of overall performance shows that saccades to the target object were disrupted by the appearance of a task-irrelevant abrupt-onset distractor when the location of this distractor did not coincide with that of the target object. Conditional Capture Function analyses revealed that, compared to young adults, older adults were more susceptible to oculomotor capture, and exhibited deficient selective suppression of the responses captured by task-irrelevant distractors. These effects were uncorrelated, suggesting two independent sources off age-related decline. The fact that these process-specific age effects remained concealed in overall oculomotor performance analyses emphasizes the utility of looking beyond the surface; indeed, there may be more than meets the eye.

Do tumor size or patient age influence the accuracy of sentinel lymph node (Sn) detection in breast cancer?

International Nuclear Information System (INIS)

Cortes, M.; Fernandez, A.; Benito, E.; Azpeitia, D.; Ricart, Y.; Escobedo, A.; Martin-Comin, J.

2002-01-01

Full text: The aim was to analyze the influence of the age of the patient and tumor size on the accuracy to identify SN in patients with breast cancer. The whole population are 250 patients with breast cancer. In 236 data on size and age were available. Mean age was 53.6 years, range 28-87 years. Patients were classified 1) depending an age: 40 60 years: 73 p and 2) depending on tumor size (mm): 30: 46 p. Examination protocol: All patients received a peritumoral injection of 111 MBq (3mCi) of 99mTc-HSA-nanocolloid in 1 - 3 ml. 2 h later 300 seconds anterior and lateral thoracic scans were obtained. A 57-Co flood phantom was positioned back to the patient to outline the anatomical contour and help to localize SN. SN was marked on the skin with permanent ink. Intraoperative SN localization was performed using a gamma probe. Histopathologic analysis of SN was done with haematoxylin/eosin, immunohistochemistry and PCR. Histopathology of the SN was compared to the histopathology of all the other lymph nodes drawn out by the surgeon. SN were identified by lymphoscintigraphy in 227 cases of 250 (91 %). 221 of them (97 %) were localized in axyla. In 210 of 221 SN could be localized and drawn out at surgery. The no detection and false negative rate were much higher in patients aged > 60 (29 and 33 %) and in tumors > 30 mm (32 and 19 %) than in patients 60 y and tumors > 30 mm (46 %) and the highest false negative rate appears in patients >60 and tumors > 30 mm (33 %) 1) No FN were found in patients with tumor size <10 mm. 2) No FN were found in patients aged under 40 years. 3) FN rate seems to be higher in older patients. 4) The age of patients and the size of tumor seem to influence an the SN detection rates. (author)

Systemic agonistic anti-CD40 treatment of tumor bearing mice modulates hepatic myeloid suppressive cells and causes immune-mediated liver damage

Science.gov (United States)

Medina-Echeverz, José; Ma, Chi; Duffy, Austin; Eggert, Tobias; Hawk, Nga; Kleiner, David E.; Korangy, Firouzeh; Greten, Tim F.

2015-01-01

Immune stimulatory monoclonal antibodies are currently evaluated as anti tumor agents. Although overall toxicity appears to be moderate, liver toxicities have been reported and are not completely understood. We studied the effect of systemic CD40 antibody treatment on myeloid cells in spleen and liver. Naïve and tumor-bearing mice were treated systemically with agonistic anti-CD40 antibody. Immune cell subsets in liver and spleen, serum transaminases and liver histologies were analyzed after antibody administration. Nox2−/−, Cd40−/− as well as bone marrow chimeric mice were used to study the mechanism by which agonistic anti-CD40 mediates its effects in vivo. Suppressor function of murine and human tumor-induced myeloid derived suppressive cells was studied upon CD40 ligation. Agonistic CD40 antibody caused liver damage within 24 hours after injection in two unrelated tumor models and mice strains. Using bone marrow chimeras we demonstrated that CD40 antibody-induced hepatitis in tumor-bearing mice was dependent on the presence of CD40-expressing hematopoietic cells. Agonistic CD40 ligation-dependent liver damage was induced by the generation of reactive oxygen species. Furthermore, agonistic CD40 antibody resulted in increased CD80 and CD40 positive liver CD11b+Gr-1+ immature myeloid cells. CD40 ligation on tumor-induced murine and human CD14+HLA-DRlow PBMC from cancer patients reduced their immune suppressor function. Collectively, agonistic CD40 antibody treatment activated tumor-induced, myeloid cells, caused myeloid dependent hepatotoxicity and ameliorated the suppressor function of murine and human MDSC. Collectively, our data suggests that CD40 may mature immunosuppressive myeloid cells and thereby cause liver damage in mice with an accumulation of tumor-induced hepatic MDSC. PMID:25637366

Degree of thyrotropin suppression as a prognostic determinant in differentiated thyroid cancer.

Science.gov (United States)

Pujol, P; Daures, J P; Nsakala, N; Baldet, L; Bringer, J; Jaffiol, C

1996-12-01

We investigate whether the prognosis of patients with differentiated thyroid cancer is improved by maintaining a greater level of TSH suppression. One hundred and forty-one patients who underwent hormone therapy after thyroidectomy were followed up from 1970 to 1993 (mean, 95 months). Patients received levothyroxine (L-T4; mean dose, 2.6 micrograms/kg-day). TSH suppression was evaluated by TRH stimulation test until 1986 and thereafter by a second generation immunoradiometric assay. As TSH underwent fluctuation over time in most patients, we focused on subgroups of patients with relatively constant TSH levels during the follow-up. The relapse-free survival (RFS) was longer in the group with constantly suppressed TSH (all TSH values, or = 1 mU/L; n = 15; P 90% of undetectable TSH values; n = 19) had a trend toward a longer RFS than the remaining population (n = 102; P = 0.14). The patients with a lesser degree of TSH suppression (< 10% of undetectable TSH values; n = 27) had a shorter RFS than the remaining patients (n = 94; P < 0.01). In multivariate analysis that included TSH suppression, age, sex, histology, and tumor node metastasis stage, the degree of TSH suppression predicted RFS independently of other factors (P = 0.02). This study shows that a lesser degree of TSH suppression is associated with an increased incidence of relapse, supporting the hypothesis that a high level of TSH suppression is required for the endocrine management of thyroid cancer.

Spinal Cord Glioneuronal Tumor with Rosetted Neuropil-Like Islands in Pediatric Age Group

Directory of Open Access Journals (Sweden)

Nil Comunoglu

2014-01-01

Full Text Available Glioneuronal neoplasms are rare tumors. Recently, an unusual glioneuronal tumor histologically showing neuropil-like islands has been described. Here, we present such a tumor originating from spinal cord of a 14-year-old girl, who has scoliosis and urinary incontinence. Microscopically, the glial component was chiefly fibrillary astrocytic, punctuated by neuropil-like islands. Immunohistochemically, glial tissue was GFAP positive, and neuropil-like areas and big neurons were synaptophysin reactive. For astrocytic component Ki-67 proliferation index was 1% and p53 was immunonegative. This case is unique in that in the literature it is the second reported case in pediatric age group that is located at spinal cord.

MiR-30a-5p suppresses tumor growth in colon carcinoma by targeting DTL

DEFF Research Database (Denmark)

Baraniskin, Alexander; Birkenkamp-Demtröder, Karin; Maghnouj, Abdelouahid

2012-01-01

MicroRNAs (miRNAs) are small non-coding RNAs that are involved in different biological processes by suppressing target gene expression. Altered expression of miR-30a-5p has been reported in colon carcinoma. To elucidate its potential biological role in colon cancer, miR-30a-5p was overexpressed via...... with in silico miRNA target prediction, we identified the denticleless protein homolog (DTL) as a potential miRNA-30a-5p target. Subsequent reporter gene assays confirmed the predicted miR-30a-5p binding site in the 3'untranslated region of DTL. Importantly, overexpression of DTL in HCT116 cells partially...... is frequently overexpressed in colorectal cancer. Thus, our data suggest that restoring miR-30a-5p function may prove useful as therapeutic strategy for tumors with reduced miR-30a-5p expression....

EGFR-targeted plasmonic magnetic nanoparticles suppress lung tumor growth by abrogating G2/M cell-cycle arrest and inducing DNA damage

Directory of Open Access Journals (Sweden)

Kuroda S

2014-08-01

G2/M checkpoint by inhibiting BRCA1, Chk1, and phospho-Cdc2/CDK1 protein expression. In vivo therapy studies showed 225-NP treatment reduced EGFR phosphorylation, increased γH2AX foci, and induced tumor cell apoptosis, resulting in suppression of tumor growth. Conclusion: The 225-NP treatment induces DNA damage and abrogates G2/M phase of the cell cycle, leading to cellular apoptosis and suppression of lung tumor growth both in vitro and in vivo. Our findings provide a rationale for combining 225-NP with other DNA-damaging agents for achieving enhanced anticancer activity. Keywords: lung cancer, epidermal growth factor receptor, autophagy

More than Meets the Eye: Age Differences in the Capture and Suppression of Oculomotor Action

Science.gov (United States)

Ridderinkhof, K. Richard; Wijnen, Jasper G.

2011-01-01

Salient visual stimuli capture attention and trigger an eye-movement toward its location reflexively, regardless of an observer’s intentions. Here we aim to investigate the effect of aging (1) on the extent to which salient yet task-irrelevant stimuli capture saccades, and (2) on the ability to selectively suppress such oculomotor responses. Young and older adults were asked to direct their eyes to a target appearing in a stimulus array. Analysis of overall performance shows that saccades to the target object were disrupted by the appearance of a task-irrelevant abrupt-onset distractor when the location of this distractor did not coincide with that of the target object. Conditional capture function analyses revealed that, compared to young adults, older adults were more susceptible to oculomotor capture, and exhibited deficient selective suppression of the responses captured by task-irrelevant distractors. These effects were uncorrelated, suggesting two independent sources off age-related decline. Thus, with advancing age, salient visual distractors become more distracting; in part because they trigger reflexive eye-movements more potently; in part because of failing top-down control over such reflexes. The fact that these process-specific age effects remained concealed in overall oculomotor performance analyses emphasizes the utility of looking beyond the surface; indeed, there may be more than meets the eye. PMID:22046165

Radiation effects on tumor-specific DTH response, 2

International Nuclear Information System (INIS)

Nobusawa, Hiroshi; Hachisu, Reiko.

1991-01-01

Tumor-specific immunity was induced in C3H mice by immunizing with syngeneic MH134 hepatoma cells. Radiation sensitivity of anti-tumor activity of immunized spleen cells were examined and compared with the radiation sensitivity of the delayed-type hypersensitivity (DTH)-response. The spleen cells were irradiated in vitro, then mixed with the tumor cells. DTH-response intensity was determined from the footpad increment twenty-four hours after inoculation of tumor cells with immunized spleen cells. Anti-tumor activity of the spleen cells, based on growth inhibition of tumor cells, was measured by a cytostatic test in vivo with diffusion chambers. Tumor-specific DTH response was suppressed dose-dependently in the range of 12-24 Gy irradiation. No suppression was observed below 12 Gy. Without irradiation, growth of tumor cells was inhibited by immunized spleen cells more effectively than by normal spleen cells. Anti-tumor activity of immunized and normal spleen cells was diminished by irradiation doses of 20 Gy and 10 Gy, respectively. Comparing our report with others that analyzed the type of anti-tumor effector cells induced in this experimental system, we concluded that tumor-specific anti-tumor activity (tumor growth inhibition in vivo) that was radiosensitive at 10-20 Gy depended on a DTH-response. (author)

Optimizing the dosing schedule of l-asparaginase improves its anti-tumor activity in breast tumor-bearing mice

Directory of Open Access Journals (Sweden)

Shoya Shiromizu

2018-04-01

Full Text Available Proliferation of acute lymphoblastic leukemic cells is nutritionally dependent on the external supply of asparagine. l-asparaginase, an enzyme hydrolyzing l-asparagine in blood, is used for treatment of acute lymphoblastic leukemic and other related blood cancers. Although previous studies demonstrated that l-asparaginase suppresses the proliferation of cultured solid tumor cells, it remains unclear whether this enzyme prevents the growth of solid tumors in vivo. In this study, we demonstrated the importance of optimizing dosing schedules for the anti-tumor activity of l-asparaginase in 4T1 breast tumor-bearing mice. Cultures of several types of murine solid tumor cells were dependent on the external supply of asparagine. Among them, we selected murine 4T1 breast cancer cells and implanted them into BALB/c female mice kept under standardized light/dark cycle conditions. The growth of 4T1 tumor cells implanted in mice was significantly suppressed by intravenous administration of l-asparaginase during the light phase, whereas its administration during the dark phase failed to show significant anti-tumor activity. Decreases in plasma asparagine levels due to the administration of l-asparaginase were closely related to the dosing time-dependency of its anti-tumor effects. These results suggest that the anti-tumor efficacy of l-asparaginase in breast tumor-bearing mice is improved by optimizing the dosing schedule. Keywords: l-asparaginase, Asparagine, Solid tumor, Chrono-pharmacotherapy

The efficacy of fat suppressed and gadolinium enhanced dynamic MR imaging in pancreatic adenocarcinomas

International Nuclear Information System (INIS)

Gabata, Toshifumi

1994-01-01

The efficacy of both fat suppressed T1-weighted imaging (T1WI) and dynamic gadolinium-enhanced MR imaging (dynamic MRI) was compared with conventional MR sequences and dynamic CT in 22 patients with histologically proven pancreatic adenocarcinoma (PAC). In the control group of 30 patients without pancreatic disease, the pancreas was shown as a markedly higher signal intensity on fat suppressed T1WI than on conventional MR sequences. The signal noise ratio (SNR) of the normal pancreas and the contrast noise ratio (CNR) between the normal pancreas and muscle were significantly higher on fat suppressed T1WI than the other MR sequences. In the group of PAC patients without chronic pancreatitis (n=14), CNR between the tumor and the normal pancreas significantly differed among imaging techniques, including fat suppressed T1WI, dynamic MRI, and the other conventional MR sequences. In the group of PAC with chronic pancreatitis (n=8), CNR between the tumor and the associated chronic pancreatitis was remarkably diminished on both fat suppressed T1WI and conventional T1WI; however, it was significantly higher on dynamic MRI than the other pulse sequences. The early phase of dynamic MRI clearly identified the tumors in the group of PAC. The capability of conventional T1WI and dynamic CT to demonstrate peripancreatic tumor extension was significantly higher than that of fat suppressed T1WI. In conclusion, fat suppressed T1WI and dynamic MRI were useful in detecting pancreatic carcinoma. (N.K.)

The combined status of ATM and p53 link tumor development with therapeutic response

DEFF Research Database (Denmark)

Jiang, Hai; Reinhardt, H Christian; Bartkova, Jirina

2009-01-01

commonly used by tumors to bypass early neoplastic checkpoints ultimately determine chemotherapeutic response and generate tumor-specific vulnerabilities that can be exploited with targeted therapies. Specifically, evaluation of the combined status of ATM and p53, two commonly mutated tumor suppressor...... genes, can help to predict the clinical response to genotoxic chemotherapies. We show that in p53-deficient settings, suppression of ATM dramatically sensitizes tumors to DNA-damaging chemotherapy, whereas, conversely, in the presence of functional p53, suppression of ATM or its downstream target Chk2...... actually protects tumors from being killed by genotoxic agents. Furthermore, ATM-deficient cancer cells display strong nononcogene addiction to DNA-PKcs for survival after DNA damage, such that suppression of DNA-PKcs in vivo resensitizes inherently chemoresistant ATM-deficient tumors to genotoxic...

Mdm2 Deficiency Suppresses MYCN-Driven Neuroblastoma Tumorigenesis In Vivo

Directory of Open Access Journals (Sweden)

Zaowen Chen

2009-08-01

Full Text Available Neuroblastoma is derived from neural crest precursor components of the peripheral sympathetic nervous system and accounts for more than 15% of all pediatric cancer deaths. A clearer understanding of the molecular basis of neuroblastoma is required for novel therapeutic approaches to improve morbidity and mortality. Neuroblastoma is uniformly p53 wild type at diagnosis and must overcome p53-mediated tumor suppression during pathogenesis. Amplification of the MYCN oncogene correlates with the most clinically aggressive form of the cancer, and MDM2, a primary inhibitor of the p53 tumor suppressor, is a direct transcriptional target of, and positively regulated by, both MYCN and MYCC. We hypothesize that MDM2 contributes to MYCN-driven tumorigenesis helping to ameliorate p53-dependent apoptotic oncogenic stress during tumor initiation and progression. To study the interaction of MYCN and MDM2, we generated an Mdm2 haploinsufficient transgenic animal model of neuroblastoma. In Mdm2+/-MYCN transgenics, tumor latency and animal survival are remarkably extended, whereas tumor incidence and growth are reduced. Analysis of the Mdm2/p53 pathway reveals remarkable p53 stabilization counterbalanced by epigenetic silencing of the p19Arf gene in the Mdm2 haploinsufficient tumors. In human neuroblastoma xenograft models, conditional small interfering RNA-mediated knockdown of MDM2 in cells expressing wild-type p53 dramatically suppresses tumor growth in a p53-dependent manner. In summary, we provided evidence for a crucial role for direct inhibition of p53 by MDM2 and suppression of the p19ARF/p53 axis in neuroblastoma tumorigenesis, supporting the development of therapies targeting these pathways.

PET measurements of hyperthermia-induced suppression of protein synthesis in tumors in relation to effects on tumor growth

International Nuclear Information System (INIS)

Daemen, B.J.; Elsinga, P.H.; Mooibroek, J.; Paans, A.M.; Wieringa, A.R.; Konings, A.W.; Vaalburg, W.

1991-01-01

Hyperthermia-induced metabolic changes in tumor tissue have been monitored by PET. Uptake of L-[1-11C]tyrosine in rhabdomyosarcoma tissue of Wag/Rij rats was dose-dependently reduced after local hyperthermia treatment at 42, 45, or 47 degrees C. Tumor blood flow, as measured by PET with 13NH3, appeared to be unchanged. The L-[1-11C]tyrosine uptake data were compared to uptake data of L-[1-14C]tyrosine and with data on the incorporation of L-[1-14C]tyrosine into tumor proteins. After intravenous injection, the 14C data were obtained from dissected tumor tissue. Heat-induced inhibition of the incorporation of L-[1-14C]tyrosine into tumor proteins tallied with the L-[1-11C]tyrosine uptake data. Heat-induced inhibition of amino acid uptake in the tumor correlated well with regression of tumor growth. It is concluded that PET using L-[1-11C]tyrosine is eligible for monitoring the effect of hyperthermia on tumor growth

Radiosynthesis, biodistribution and imaging of [11C]YM155, a novel survivin suppressant, in a human prostate tumor-xenograft mouse model

International Nuclear Information System (INIS)

Murakami, Yoshihiro; Matsuya, Takahiro; Kita, Aya; Yamanaka, Kentaro; Noda, Akihiro; Mitsuoka, Keisuke; Nakahara, Takahito; Miyoshi, Sosuke; Nishimura, Shintaro

2013-01-01

Introduction: Sepantronium bromide (YM155) is an antitumor drug in development and is a first-in-class chemical entity, which is a survivin suppressant. We developed a radiosynthesis of [ 11 C]YM155 to non-invasively evaluate its tissue and tumor distribution in mice bearing human prostate tumor xenografts. Methods: Methods utilizing [ 11 C]acetyl chloride and [ 11 C]methyl triflate, both accessible with automated radiosynthesis boxes, were evaluated. The O-methylation of ethanolamine-alkolate with [ 11 C]methyl triflate proved to be the key development toward a rapid and efficient process. The whole-body distribution of [ 11 C]YM155 in PC-3 xenografted mice was examined using a planar positron imaging system (PPIS). Results: Sufficient quantities of radiopharmaceutical grade [ 11 C]YM155 were produced for our PET imaging and distribution studies. The decay corrected (EOB) radiochemical yield was 16–22%, within a synthesis time of 47 min. The radiochemical purity was higher than 99%, and the specific activity was 29–60 GBq/μmol (EOS). High uptake levels of radioactivity (%ID/g, mean ± SE) were observed in tumor (0.0613 ± 0.0056), kidneys (0.0513 ± 0.0092), liver (0.0368 ± 0.0043) and cecum (0.0623 ± 0.0070). The highest tumor uptake was observed at an early time point (from 10 min after) following injection. Tumor-to-blood and tumor-to-muscle uptake ratios of [ 11 C]YM155, at 40 min after injection, were 26.5 (± 2.9) and 25.6 (± 3.6), respectively. Conclusion: A rapid method for producing a radiopharmaceutical grade [ 11 C]YM155 was developed. An in vivo distribution study using PPIS showed high uptake of [ 11 C]YM155 in tumor tissue. Our methodology may facilitate the evaluation and prediction of response to YM155, when given as an anti-cancer agent

Estradiol suppresses tissue androgens and prostate cancer growth in castration resistant prostate cancer

International Nuclear Information System (INIS)

Montgomery, Bruce; Nelson, Peter S; Vessella, Robert; Kalhorn, Tom; Hess, David; Corey, Eva

2010-01-01

Estrogens suppress tumor growth in prostate cancer which progresses despite anorchid serum androgen levels, termed castration resistant prostate cancers (CRPC), although the mechanisms are unclear. We hypothesize that estrogen inhibits CRPC in anorchid animals by suppressing tumoral androgens, an effect independent of the estrogen receptor. The human CRPC xenograft LuCaP 35V was implanted into orchiectomized male SCID mice and established tumors were treated with placebo, 17β-estradiol or 17β-estradiol and estrogen receptor antagonist ICI 182,780. Effects of 17β-estradiol on tumor growth were evaluated and tissue testosterone (T) and dihydrotestosterone (DHT) evaluated by mass spectrometry. Treatment of LuCaP 35V with 17β-estradiol slowed tumor growth compared to controls (tumor volume at day 21: 785 ± 81 mm 3 vs. 1195 ± 84 mm 3 , p = 0.002). Survival was also significantly improved in animals treated with 17β-estradiol (p = 0.03). The addition of the estrogen receptor antagonist ICI 182,780 did not significantly change survival or growth. 17β-estradiol in the presence and absence of ICI 182,780 suppressed tumor testosterone (T) and dihydrotestosterone (DHT) as assayed by mass spectrometry. Tissue androgens in placebo treated LuCaP 35V xenografts were; T = 0.71 ± 0.28 pg/mg and DHT = 1.73 ± 0.36 pg/mg. In 17β-estradiol treated LuCaP35V xenografts the tissue androgens were, T = 0.20 ± 0.10 pg/mg and DHT = 0.15 ± 0.15 pg/mg, (p < 0.001 vs. controls). Levels of T and DHT in control liver tissue were < 0.2 pg/mg. CRPC in anorchid animals maintains tumoral androgen levels despite castration. 17β-estradiol significantly suppressed tumor T and DHT and inhibits growth of CRPC in an estrogen receptor independent manner. The ability to manipulate tumoral androgens will be critical in the development and testing of agents targeting CRPC through tissue steroidogenesis

Optimizing the dosing schedule of l-asparaginase improves its anti-tumor activity in breast tumor-bearing mice.

Science.gov (United States)

Shiromizu, Shoya; Kusunose, Naoki; Matsunaga, Naoya; Koyanagi, Satoru; Ohdo, Shigehiro

2018-04-01

Proliferation of acute lymphoblastic leukemic cells is nutritionally dependent on the external supply of asparagine. l-asparaginase, an enzyme hydrolyzing l-asparagine in blood, is used for treatment of acute lymphoblastic leukemic and other related blood cancers. Although previous studies demonstrated that l-asparaginase suppresses the proliferation of cultured solid tumor cells, it remains unclear whether this enzyme prevents the growth of solid tumors in vivo. In this study, we demonstrated the importance of optimizing dosing schedules for the anti-tumor activity of l-asparaginase in 4T1 breast tumor-bearing mice. Cultures of several types of murine solid tumor cells were dependent on the external supply of asparagine. Among them, we selected murine 4T1 breast cancer cells and implanted them into BALB/c female mice kept under standardized light/dark cycle conditions. The growth of 4T1 tumor cells implanted in mice was significantly suppressed by intravenous administration of l-asparaginase during the light phase, whereas its administration during the dark phase failed to show significant anti-tumor activity. Decreases in plasma asparagine levels due to the administration of l-asparaginase were closely related to the dosing time-dependency of its anti-tumor effects. These results suggest that the anti-tumor efficacy of l-asparaginase in breast tumor-bearing mice is improved by optimizing the dosing schedule. Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Enhancement of anticancer effect of interferon-γ gene transfer against interferon-γ-resistant tumor by depletion of tumor-associated macrophages.

Science.gov (United States)

Kiyota, Tsuyoshi; Takahashi, Yuki; Watcharanurak, Kanitta; Nishikawa, Makiya; Ohara, Saori; Ando, Mitsuru; Watanabe, Yoshihiko; Takakura, Yoshinobu

2014-05-05

Tumor-associated macrophages (TAMs) negatively affect the therapeutic effects of anticancer agents. To examine the role of TAMs in interferon (IFN)-γ gene therapy, we selected two types of solid tumors, which varied in the number of TAMs, and investigated the effects of IFN-γ gene transfer on tumor growth. Many TAMs were detected in the solid tumors of murine adenocarcinoma colon-26 cells, whereas few TAMs were detected in murine melanoma B16-BL6 cells. IFN-γ gene transfer hardly suppressed the growth of colon-26 tumors, whereas it was effective in suppressing the growth of B16-BL6 tumors. The antiproliferative effects of IFN-γ on cultured colon-26 cells were similar to those on cultured B16-BL6 cells. To evaluate the role of TAMs, we injected clodronate liposomes (CLs) modified with poly(ethylene glycol) (PEG) to functionally deplete TAMs in tumor-bearing mice. Repeated injections of PEG-CLs significantly retarded the growth of colon-26 tumors and combination with IFN-γ gene transfer further inhibited the growth. In contrast, PEG-CLs hardly retarded the growth of B16-BL6 tumors. These results clearly indicate that TAM depletion is effective in enhancing the therapeutic effect of IFN-γ in TAM-repleted and IFN-γ-resistant tumors.

Dynamic Alu Methylation during Normal Development, Aging, and Tumorigenesis

Directory of Open Access Journals (Sweden)

Yanting Luo

2014-01-01

Full Text Available DNA methylation primarily occurs on CpG dinucleotides and plays an important role in transcriptional regulations during tissue development and cell differentiation. Over 25% of CpG dinucleotides in the human genome reside within Alu elements, the most abundant human repeats. The methylation of Alu elements is an important mechanism to suppress Alu transcription and subsequent retrotransposition. Decades of studies revealed that Alu methylation is highly dynamic during early development and aging. Recently, many environmental factors were shown to have a great impact on Alu methylation. In addition, aberrant Alu methylation has been documented to be an early event in many tumors and Alu methylation levels have been associated with tumor aggressiveness. The assessment of the Alu methylation has become an important approach for early diagnosis and/or prognosis of cancer. This review focuses on the dynamic Alu methylation during development, aging, and tumor genesis. The cause and consequence of Alu methylation changes will be discussed.

Differentiation-inducing factor-1 suppresses gene expression of cyclin D1 in tumor cells

International Nuclear Information System (INIS)

Yasmin, Tania; Takahashi-Yanaga, Fumi; Mori, Jun; Miwa, Yoshikazu; Hirata, Masato; Watanabe, Yutaka; Morimoto, Sachio; Sasaguri, Toshiyuki

2005-01-01

To determine the mechanism by which differentiation-inducing factor-1 (DIF-1), a morphogen of Dictyostelium discoideum, inhibits tumor cell proliferation, we examined the effect of DIF-1 on the gene expression of cyclin D1. DIF-1 strongly reduced the expression of cyclin D1 mRNA and correspondingly decreased the amount of β-catenin in HeLa cells and squamous cell carcinoma cells. DIF-1 activated glycogen synthase kinase-3β (GSK-3β) and inhibition of GSK-3β attenuated the DIF-1-induced β-catenin degradation, indicating the involvement of GSK-3β in this effect. Moreover, DIF-1 reduced the activities of T-cell factor (TCF)/lymphoid enhancer factor (LEF) reporter plasmid and a reporter gene driven by the human cyclin D1 promoter. Eliminating the TCF/LEF consensus site from the cyclin D1 promoter diminished the effect of DIF-1. These results suggest that DIF-1 inhibits Wnt/β-catenin signaling, resulting in the suppression of cyclin D1 promoter activity

New Chimeric Antigen Receptor Design for Solid Tumors

Directory of Open Access Journals (Sweden)

Yuedi Wang

2017-12-01

Full Text Available In recent years, chimeric antigen receptor (CAR T-cell therapy has become popular in immunotherapy, particularly after its tremendous success in the treatment of lineage-restricted hematologic cancers. However, the application of CAR T-cell therapy for solid tumors has not reached its full potential because of the lack of specific tumor antigens and inhibitory factors in suppressive tumor microenvironment (TME (e.g., programmed death ligand-1, myeloid-derived suppressor cells, and transforming growth factor-β. In this review, we include some limitations in CAR design, such as tumor heterogeneity, indefinite spatial distance between CAR T-cell and its target cell, and suppressive TME. We also summarize some new approaches to overcome these hurdles, including targeting neoantigens and/or multiple antigens at once and depleting some inhibitory factors.

Impact of aging on neurocognitive performance in previously antiretroviral-naive HIV-infected individuals on their first suppressive regimen.

Science.gov (United States)

Coban, Hamza; Robertson, Kevin; Smurzynski, Marlene; Krishnan, Supriya; Wu, Kunling; Bosch, Ronald J; Collier, Ann C; Ellis, Ronald J

2017-07-17

Despite treatment with virologically suppressive antiretroviral therapy (ART), neurocognitive impairment may persist or develop de novo in aging HIV-infected individuals. We evaluated advancing age as a predictor of neurocognitive impairment in a large cohort of previously ART-naive individuals on long-term ART. The AIDS Clinical Trials Group Longitudinal Linked Randomized Trials was a prospective cohort study of HIV-infected individuals originally enrolled in randomized ART trials. This analysis examined neurocognitive outcomes at least 2 years after ART initiation. All participants underwent annual neurocognitive testing consisting of Trail making A and B, the wechsler adult intelligence scale-revised Digit Symbol and Hopkins Verbal Learning Tests. Uni and multivariable repeated measures regression models evaluated factors associated with neurocognitive performance. Predictors at parent study entry (ART naive) included entry demographics, smoking, injection drug use, hepatitis B surface antigen, hepatitis C virus serostatus, history of stroke, ART regimen type, pre-ART nadir CD4 cell count, and plasma viral load and as well as time-updated plasma viral load and CD4 cell count. The cohort comprised 3313 individuals with median pre-ART age of 38 years, 20% women; 36% Black, non-Hispanic; 22% Hispanic. Virologic suppression was maintained at 91% of follow-up visits. Neurocognitive performance improved with years of ART. After adjusting for the expected effects of age using norms from HIV-negative individuals, the odds of neurocognitive impairment at follow-up visits among the HIV infected increased by nearly 20% for each decade of advancing age. Despite continued virologic suppression and neurocognitive improvement in the cohort as a whole, older individuals were more likely to have neurocognitive impairment than younger individuals.

Tumor-Protective Mechanism Identified from Premature Aging Disease | Center for Cancer Research

Science.gov (United States)

Hutchinson-Gilford Progeria Syndrome (HGPS) is an extraordinarily rare genetic disorder caused by a mutation in the LMNA gene, which encodes architectural proteins of the human cell nucleus. The mutation causes the production of a mutant protein called progerin. Patients with HGPS display signs of premature aging, such as hair loss, slowed growth, weakening of bone and joint integrity, and cardiovascular disease. Most die in their mid-teens of heart disease or stroke. Intriguingly, these patients do not develop another aging-related disease, cancer, despite having dramatically elevated levels of DNA damage. Tom Misteli, Ph.D., of CCR’s Laboratory of Receptor Biology and Gene Expression, and his colleagues hypothesized that, rather than patients not living long enough to develop cancer, a resistance mechanism was operating in HGPS cells to prevent cancer formation. To begin testing this idea, the researchers transformed fibroblasts from HGPS patients or age-matched, healthy controls with telomerase, constitutively-activated HRAS, and SV40 large and small T antigens. Transformed HGPS cells displayed morphological changes and increased proliferation similar to transformed controls but formed fewer colonies in soft agar and fewer tumors when injected into mice. When the investigators examined global gene expression in the two populations of cells, they found that transformed HGPS cells failed to activate many of the genes that are induced in response to transformation in controls, including oncogenic and proliferation pathways. In addition the transformed HGPS cells were unable to undergo oncogenic de-differentiation. Importantly, the tumor resistance in HGPS cells was due to the presence of the progerin protein, which was both necessary and sufficient to protect cells from oncogenic transformation. Together these results suggested that HGPS cells resist cancer-inducing stimuli by not undergoing the genetic reprogramming necessary for tumor initiation. The scientists

Inhibition of PI3K by ZSTK474 suppressed tumor growth not via apoptosis but G0/G1 arrest

International Nuclear Information System (INIS)

Dan, Shingo; Yoshimi, Hisashi; Okamura, Mutsumi; Mukai, Yumiko; Yamori, Takao

2009-01-01

Phosphoinositide 3-kinase (PI3K) is a potential target in cancer therapy. Inhibition of PI3K is believed to induce apoptosis. We recently developed a novel PI3K inhibitor ZSTK474 with antitumor efficacy. In this study, we have examined the underlying mode of action by which ZSTK474 exerts its antitumor efficacy. In vivo, ZSTK474 effectively inhibited the growth of human cancer xenografts. In parallel, ZSTK474 treatment suppressed the expression of phospho-Akt, suggesting effective PI3K inhibition, and also suppressed the expression of nuclear cyclin D1 and Ki67, both of which are hallmarks of proliferation. However, ZSTK474 treatment did not increase TUNEL-positive apoptotic cells. In vitro, ZSTK474 induced marked G 0 /G 1 arrest, but did not increase the subdiploid cells or activate caspase, both of which are hallmarks of apoptosis. These results clearly indicated that inhibition of PI3K by ZSTK474 did not induce apoptosis but rather induced strong G 0 /G 1 arrest, which might cause its efficacy in tumor cells.

Suppression of choriocarcinoma invasion and metastasis following blockade of BDNF/TrkB signaling

International Nuclear Information System (INIS)

Kawamura, Kazuhiro; Kawamura, Nanami; Okamoto, Naoki; Manabe, Motomu

2013-01-01

Brain-derived neurotrophic factor (BDNF) acts through its cognate receptor tyrosine kinase-B (TrkB) to regulate diverse physiological functions in reproductive and other tissues. In normal and malignant trophoblastic cells, the BDNF/TrkB signaling promotes cell growth. Due to the highly malignant nature of choriocarcinoma, we investigated possible involvement of this system in choriocarcinoma cell invasion and metastasis. We demonstrated that treatment of cultured choriocarcinoma cells, known to express both BDNF and TrkB, with a soluble TrkB ectodomain or a Trk receptor inhibitor K252a suppressed cell invasion accompanied with decreased expression of matrix metalloproteinase-2, a cell invasion marker. In vivo studies using a tumor xenograft model in athymic nude mice further showed inhibition of cell invasion from tumors to surrounding tissues following the suppression of endogenous TrkB signaling. For an in vivo model of choriocarcinoma metastasis, we performed intravenous injections of JAR cells expressing firefly luciferase into severe combined immunodeficiency (SCID) mice. Treatment with K252a inhibited metastasis of tumors to distant organs. In vivo K252a treatment also suppressed metastatic tumor growth as reflected by decreased cell proliferation and increased apoptosis and caspases-3/7 activities, together with reduced tissue levels of a tumor marker, human chorionic gonadotropin-β. In vivo suppression of TrkB signaling also led to decreased expression of angiogenic markers in metastatic tumor, including cluster of differentiation 31 and vascular endothelial growth factor A. Our findings suggested essential autocrine/paracrine roles of the BDNF/TrkB signaling system in choriocarcinoma invasion and metastasis. Inhibition of this signaling could serve as the basis to develop a novel therapy for patients with choriocarcinoma

Boswellic acid suppresses growth and metastasis of human pancreatic tumors in an orthotopic nude mouse model through modulation of multiple targets.

Directory of Open Access Journals (Sweden)

Byoungduck Park

Full Text Available Pancreatic cancer (PaCa is one of the most lethal cancers, with an estimated 5-year survival of <5% even when patients are given the best treatment available. In addition, these treatments are often toxic and expensive, thus new agents which are safe, affordable and effective are urgently needed. We describe here the results of our study with acetyl-11-keto-β-boswellic acid (AKBA, an agent obtained from an Ayurvedic medicine, gum resin of Boswellia serrata. Whether AKBA has an activity against human PaCa, was examined in in vitro models and in an orthotopic nude mouse model of PaCa. We found that AKBA inhibited the proliferation of four different PaCa cell lines (AsPC-1, PANC-28, and MIA PaCa-2 with K-Ras and p53 mutations, and BxPC-3 with wild-type K-Ras and p53 mutation. These effects correlated with an inhibition of constitutively active NF-κB and suppression of NF-κB regulating gene expression. AKBA also induced apoptosis, and sensitized the cells to apoptotic effects of gemcitabine. In the orthotopic nude mouse model of PaCa, p.o. administration of AKBA alone (100 mg/kg significantly inhibited the tumor growth; this activity was enhanced by gemcitabine. In addition, AKBA inhibited the metastasis of the PaCa to spleen, liver, and lungs. This correlated with decreases in Ki-67, a biomarker of proliferation, and CD31, a biomarker of microvessel density, in the tumor tissue. AKBA produced significant decreases in the expression of NF-κB regulating genes in the tissues. Immunohistochemical analysis also showed AKBA downregulated the expression of COX-2, MMP-9, CXCR4, and VEGF in the tissues. Overall these results demonstrate that AKBA can suppress the growth and metastasis of human pancreatic tumors in an orthotopic nude mouse model that correlates with modulation of multiple targets.

Protein kinase C (PKC) isoforms in cancer, tumor promotion and tumor suppression.

Science.gov (United States)

Isakov, Noah

2018-02-01

The AGC family of serine/threonine kinases (PKA, PKG, PKC) includes more than 60 members that are critical regulators of numerous cellular functions, including cell cycle and differentiation, morphogenesis, and cell survival and death. Mutation and/or dysregulation of AGC kinases can lead to malignant cell transformation and contribute to the pathogenesis of many human diseases. Members of one subgroup of AGC kinases, the protein kinase C (PKC), have been singled out as critical players in carcinogenesis, following their identification as the intracellular receptors of phorbol esters, which exhibit tumor-promoting activities. This observation attracted the attention of researchers worldwide and led to intense investigations on the role of PKC in cell transformation and the potential use of PKC as therapeutic drug targets in cancer diseases. Studies demonstrated that many cancers had altered expression and/or mutation of specific PKC genes. However, the causal relationships between the changes in PKC gene expression and/or mutation and the direct cause of cancer remain elusive. Independent studies in normal cells demonstrated that activation of PKC is essential for the induction of cell activation and proliferation, differentiation, motility, and survival. Based on these observations and the general assumption that PKC isoforms play a positive role in cell transformation and/or cancer progression, many PKC inhibitors have entered clinical trials but the numerous attempts to target PKC in cancer has so far yielded only very limited success. More recent studies demonstrated that PKC function as tumor suppressors, and suggested that future clinical efforts should focus on restoring, rather than inhibiting, PKC activity. The present manuscript provides some historical perspectives on the tumor promoting function of PKC, reviewing some of the observations linking PKC to cancer progression, and discusses the role of PKC in the pathogenesis of cancer diseases and its

The effect of intense intermittent training with and without taking vitamin E on mRNA expression of p53/PTEN tumor suppressing genes in prostate glands of male rats

Directory of Open Access Journals (Sweden)

Mohammad Esmaeil Afzalpour

2016-11-01

Full Text Available Physical activity and diet are the most important modifiable determinants of cancer risk. The objective of this study was to examine the effect of intense intermittent training with and without taking vitamin E on expression of p53 and PTEN tumor suppressing genes in the prostate gland of male rats. For this purpose, 50 Sprague-Dawley male rats were randomly assigned into 5 groups: [1] control (CON, n = 10, [2] sham (S, n = 10, [3] intense intermittent training (IIT, n = 10, [4] intense intermittent training + vitamin E (IIT + VE, n = 10, [5] vitamin E (VE, n = 10. Protocol of this study was implemented for 6 days per week for 6 weeks, with observing the overload principle on the motorized treadmill. After implementing training protocol, expression rate of p53 and PTEN genes reduced significantly (p<0.000, p<0.031, respectively. Taking vitamin E with intermittent training caused significant reduction in p53 expression (p<0.013, while it caused significant increase in expression of PTEN (p<0.035. These results showed that intense intermittent training reduces expression of p53 and PTEN tumor suppressing genes and taking supplementation vitamin E along with this type of training could cause different effects in expression of these tumor suppressor genes.

Epigallocatechin-3-gallate suppresses the expression of HSP70 and HSP90 and exhibits anti-tumor activity in vitro and in vivo

International Nuclear Information System (INIS)

Tran, Phan LCHB; Kim, Soo-A; Choi, Hong Seok; Yoon, Jung-Hoon; Ahn, Sang-Gun

2010-01-01

Epigallocatechin-3-gallate (EGCG), one of the major catechins in green tea, is a potential chemopreventive agent for various cancers. The aim of this study was to examine the effect of EGCG on the expression of heat shock proteins (HSPs) and tumor suppression. Cell colony formation was evaluated by a soft agar assay. Transcriptional activity of HSP70 and HSP90 was determined by luciferase reporter assay. An EGCG-HSPs complex was prepared using EGCG attached to the cyanogen bromide (CNBr)-activated Sepharose 4B. In vivo effect of EGCG on tumor growth was examined in a xenograft model. Treatment with EGCG decreased cell proliferation and colony formation of MCF-7 human breast cancer cells. EGCG specifically inhibited the expression of HSP70 and HSP90 by inhibiting the promoter activity of HSP70 and HSP90. Pretreatment with EGCG increased the stress sensitivity of MCF-7 cells upon heat shock (44°C for 1 h) or oxidative stress (H 2 O 2 , 500 μM for 24 h). Moreover, treatment with EGCG (10 mg/kg) in a xenograft model resulted in delayed tumor incidence and reduced tumor size, as well as the inhibition of HSP70 and HSP90 expression. Overall, these findings demonstrate that HSP70 and HSP90 are potent molecular targets of EGCG and suggest EGCG as a drug candidate for the treatment of human cancer

Exosomes serve as nanoparticles to suppress tumor growth and angiogenesis in gastric cancer by delivering hepatocyte growth factor siRNA.

Science.gov (United States)

Zhang, Haiyang; Wang, Yi; Bai, Ming; Wang, Junyi; Zhu, Kegan; Liu, Rui; Ge, Shaohua; Li, JiaLu; Ning, Tao; Deng, Ting; Fan, Qian; Li, Hongli; Sun, Wu; Ying, Guoguang; Ba, Yi

2018-03-01

Exosomes derived from cells have been found to mediate signal transduction between cells and to act as efficient carriers to deliver drugs and small RNA. Hepatocyte growth factor (HGF) is known to promote the growth of both cancer cells and vascular cells, and the HGF-cMET pathway is a potential clinical target. Here, we characterized the inhibitory effect of HGF siRNA on tumor growth and angiogenesis in gastric cancer. In addition, we showed that HGF siRNA packed in exosomes can be transported into cancer cells, where it dramatically downregulates HGF expression. A cell co-culture model was used to show that exosomes loaded with HGF siRNA suppress proliferation and migration of both cancer cells and vascular cells. Moreover, exosomes were able to transfer HGF siRNA in vivo, decreasing the growth rates of tumors and blood vessels. The results of our study demonstrate that exosomes have potential for use in targeted cancer therapy by delivering siRNA. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Endogenous leptin contributes to baroreflex suppression within the solitary tract nucleus of aged rats

Science.gov (United States)

Arnold, Amy C.

2014-01-01

The decline in cardiovagal baroreflex function that occurs with aging is accompanied by an increase in circulating leptin levels. Our previous studies showed that exogenous leptin impairs the baroreflex sensitivity for control of heart rate in younger rats, but the contribution of this hormone to baroreflex dysfunction during aging is unknown. Thus we assessed the effect of bilateral leptin microinjection (500 fmol/60 nl) within the solitary tract nucleus (NTS) on the baroreflex sensitivity in older (66 ± 2 wk of age) urethane/chloralose anesthetized Sprague-Dawley rats with elevated circulating leptin levels. In contrast to the 63% reduction observed in younger rats, leptin did not alter the baroreflex sensitivity for bradycardia evoked by phenylephrine in older rats (0.76 ± 0.19 baseline vs. 0.71 ± 0.15 ms/mmHg after leptin; P = 0.806). We hypothesized that this loss of sensitivity reflected endogenous suppression of the baroreflex by elevated leptin, rather than cardiovascular resistance to the peptide. Indeed, NTS administration of a leptin receptor antagonist (75 pmol/120 nl) improved the baroreflex sensitivity for bradycardia in older rats (0.73 ± 0.13 baseline vs. 1.19 ± 0.26 at 10 min vs. 1.87 ± 0.32 at 60 min vs. 1.22 ± 0.54 ms/mmHg at 120 min; P = 0.002), with no effect in younger rats. There was no effect of the leptin antagonist on the baroreflex sensitivity for tachycardia, responses to cardiac vagal chemosensitive fiber activation, or resting hemodynamics in older rats. These findings suggest that the actions of endogenous leptin within the NTS, either produced locally or derived from the circulation, contribute to baroreflex suppression during aging. PMID:25260611

Histological type and grade of breast cancer tumors by parity, age at birth, and time since birth: a register-based study in Norway

International Nuclear Information System (INIS)

Albrektsen, Grethe; Heuch, Ivar; Thoresen, Steinar Ø

2010-01-01

Some studies have indicated that reproductive factors affect the risk of histological types of breast cancer differently. The long-term protective effect of a childbirth is preceded by a short-term adverse effect. Few studies have examined whether tumors diagnosed shortly after birth have specific histological characteristics. In the present register-based study, comprising information for 22,867 Norwegian breast cancer cases (20-74 years), we examined whether histological type (9 categories) and grade of tumor (2 combined categories) differed by parity or age at first birth. Associations with time since birth were evaluated among 9709 women diagnosed before age 50 years. Chi-square tests were applied for comparing proportions, whereas odds ratios (each histological type vs. ductal, or grade 3-4 vs. grade 1-2) were estimated in polytomous and binary logistic regression analyses. Ductal tumors, the most common histological type, accounted for 81.4% of all cases, followed by lobular tumors (6.3%) and unspecified carcinomas (5.5%). Other subtypes accounted for 0.4%-1.5% of the cases each. For all histological types, the proportions differed significantly by age at diagnoses. The proportion of mucinous and tubular tumors decreased with increasing parity, whereas Paget disease and medullary tumors were most common in women of high parity. An increasing trend with increasing age at first birth was most pronounced for lobular tumors and unspecified carcinomas; an association in the opposite direction was seen in relation to medullary and tubular tumors. In age-adjusted analyses, only the proportions of unspecified carcinomas and lobular tumors decreased significantly with increasing time since first and last birth. However, ductal tumors, and malignant sarcomas, mainly phyllodes tumors, seemed to occur at higher frequency in women diagnosed <2 years after first childbirth. The proportions of medullary tumors and Paget disease were particularly high among women diagnosed 2

Bronchial carcinoid tumors: A rare malignant tumor

African Journals Online (AJOL)

2015-02-03

Feb 3, 2015 ... Nigerian Journal of Clinical Practice • Sep-Oct 2015 • Vol 18 • Issue 5. Abstract. Bronchial carcinoid tumors (BCTs) are an uncommon group of lung tumors. They commonly affect the young adults and the middle aged, the same age group affected by other more common chronic lung conditions such as ...

[Immune system and tumors].

Science.gov (United States)

Terme, Magali; Tanchot, Corinne

2017-02-01

Despite having been much debated, it is now well established that the immune system plays an essential role in the fight against cancer. In this article, we will highlight the implication of the immune system in the control of tumor growth and describe the major components of the immune system involved in the antitumoral immune response. The immune system, while exerting pressure on tumor cells, also will play a pro-tumoral role by sculpting the immunogenicity of tumors cells as they develop. Finally, we will illustrate the numerous mechanisms of immune suppression that take place within the tumoral microenvironment which allow tumor cells to escape control from the immune system. The increasingly precise knowledge of the brakes to an effective antitumor immune response allows the development of immunotherapy strategies more and more innovating and promising of hope. Copyright © 2016. Published by Elsevier Masson SAS.

Both p53-PUMA/NOXA-Bax-mitochondrion and p53-p21cip1 pathways are involved in the CDglyTK-mediated tumor cell suppression

International Nuclear Information System (INIS)

Yu, Zhendong; Wang, Hao; Zhang, Libin; Tang, Aifa; Zhai, Qinna; Wen, Jianxiang; Yao, Li; Li, Pengfei

2009-01-01

CDglyTK fusion suicide gene has been well characterized to effectively kill tumor cells. However, the exact mechanism and downstream target genes are not fully understood. In our study, we found that CDglyTK/prodrug treatment works more efficiently in p53 wild-type (HONE1) cells than in p53 mutant (CNE1) cells. We then used adenovirus-mediated gene delivery system to either knockdown or overexpress p53 and its target genes in these cells. Consistent results showed that both p53-PUMA/NOXA/Bcl2-Bax and p53-p21 pathways contribute to the CDglyTK induced tumor cell suppression. Our work for the first time addressed the role of p53 related genes in the CDglyTK/prodrug system.

Both p53-PUMA/NOXA-Bax-mitochondrion and p53-p21cip1 pathways are involved in the CDglyTK-mediated tumor cell suppression

Energy Technology Data Exchange (ETDEWEB)

Yu, Zhendong, E-mail: zdyu@hotmail.com [Department of Clinical laboratory, Peking University Shenzhen Hospital, Guangdong (China); Wang, Hao [Department of pathology, The Chinese University of Hong Kong, Hong Kong (China); Zhang, Libin; Tang, Aifa; Zhai, Qinna; Wen, Jianxiang; Yao, Li [Department of Clinical laboratory, Peking University Shenzhen Hospital, Guangdong (China); Li, Pengfei, E-mail: lipengfei@cuhk.edu.hk [Department of pathology, The Chinese University of Hong Kong, Hong Kong (China)

2009-09-04

CDglyTK fusion suicide gene has been well characterized to effectively kill tumor cells. However, the exact mechanism and downstream target genes are not fully understood. In our study, we found that CDglyTK/prodrug treatment works more efficiently in p53 wild-type (HONE1) cells than in p53 mutant (CNE1) cells. We then used adenovirus-mediated gene delivery system to either knockdown or overexpress p53 and its target genes in these cells. Consistent results showed that both p53-PUMA/NOXA/Bcl2-Bax and p53-p21 pathways contribute to the CDglyTK induced tumor cell suppression. Our work for the first time addressed the role of p53 related genes in the CDglyTK/prodrug system.

Complete suppression of in vivo growth of human leukemia cells by specific immunotoxins: nude mouse models

International Nuclear Information System (INIS)

Hara, H.; Seon, B.K.

1987-01-01

In this study, immunotoxins containing monoclonal anti-human T-cell leukemia antibodies are shown to be capable of completely suppressing the tumor growth of human T-cell leukemia cells in vivo without any overt undersirable toxicity. These immunotoxins were prepared by conjugating ricin A chain (RA) with our monoclonal antibodies, SN1 and SN2, directed specifically to the human T-cell leukemia cell surface antigens TALLA and GP37, respectively. The authors have shown that these monoclonal antibodies are highly specific for human T-cell leukemia cells and do not react with various normal cells including normal T and B cells, thymocytes, and bone marrow cells. Ascitic and solid human T-cell leukemia cell tumors were generated in nude mice. The ascitic tumor was generated by transplanting Ichikawa cells (a human T-cell leukemia cell) i.p. into nude mice, whereas the solid tumor was generated by transplanting s.c. MOLT-4 cells (a human T-cell leukemia cell line) and x-irradiated human fibrosarcoma cells into x-irradiated nude mice. To investigate the efficacy of specific immunotoxins in suppression the in vivo growth of the ascitic tumor, they divided 40 nude mice that were injected with Ichikawa cells into four groups. None of the mice in group 4 that were treated with SN1-RA and SN2-RA showed any signs of a tumor or undesirable toxic effects for the 20 weeks that they were followed after the transplantation. Treatment with SN1-RA plus SN2-RA completely suppressed solid tumor growth in 4 of 10 nude mice carrying solid tumors and partially suppressed the tumor growth in the remaining 6 nude mice. These results strongly suggest that SN1-RA and SN2-RA may be useful for clinical treatment

CT and MR imaging features in phosphaturic mesenchymal tumor-mixed connective tissue: A case report.

Science.gov (United States)

Shi, Zhenshan; Deng, Yiqiong; Li, Xiumei; Li, Yueming; Cao, Dairong; Coossa, Vikash Sahadeo

2018-04-01

Phosphaturic mesenchymal tumor-mixed connective tissue (PMT-MCT) is rare and usually benign and slow-growing. The majority of these tumors is associated with sporadic tumor-induced osteomalacia (TIO) or rickets, affect middle-aged individuals and are located in the extremities. Previous imaging studies often focused on seeking the causative tumors of TIO, not on the radiological features of these tumors, especially magnetic resonance imaging (MRI) features. PMT-MCT remains a largely misdiagnosed, ignored or unknown entity by most radiologists and clinicians. In the present case report, a review of the known literature of PMT-MCT was conducted and the CT and MRI findings from three patient cases were described for diagnosing the small subcutaneous tumor. Typical MRI appearances of PMT-MCT were isointense relative to the muscles on T1-weighted imaging, and markedly hyperintense on T2-weighted imaging containing variably flow voids, with markedly heterogeneous/homogenous enhancement on post contrast T1-weighted fat-suppression imaging. Short time inversion recovery was demonstrated to be the optimal sequence in localizing the tumor.

Turmeric (Curcuma longa) inhibits inflammatory nuclear factor (NF)-κB and NF-κB-regulated gene products and induces death receptors leading to suppressed proliferation, induced chemosensitization, and suppressed osteoclastogenesis.

Science.gov (United States)

Kim, Ji H; Gupta, Subash C; Park, Byoungduck; Yadav, Vivek R; Aggarwal, Bharat B

2012-03-01

The incidence of cancer is significantly lower in regions where turmeric is heavily consumed. Whether lower cancer incidence is due to turmeric was investigated by examining its effects on tumor cell proliferation, on pro-inflammatory transcription factors NF-κB and STAT3, and on associated gene products. Cell proliferation and cell cytotoxicity were measured by the MTT method, NF-κB activity by EMSA, protein expression by Western blot analysis, ROS generation by FACS analysis, and osteoclastogenesis by TRAP assay. Turmeric inhibited NF-κB activation and down-regulated NF-κB-regulated gene products linked to survival (Bcl-2, cFLIP, XIAP, and cIAP1), proliferation (cyclin D1 and c-Myc), and metastasis (CXCR4) of cancer cells. The spice suppressed the activation of STAT3, and induced the death receptors (DR)4 and DR5. Turmeric enhanced the production of ROS, and suppressed the growth of tumor cell lines. Furthermore, turmeric sensitized the tumor cells to chemotherapeutic agents capecitabine and taxol. Turmeric was found to be more potent than pure curcumin for cell growth inhibition. Turmeric also inhibited NF-κB activation induced by RANKL that correlated with the suppression of osteoclastogenesis. Our results indicate that turmeric can effectively block the proliferation of tumor cells through the suppression of NF-κB and STAT3 pathways. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Peptides Derived from Type IV Collagen, CXC Chemokines, and Thrombospondin-1 Domain-Containing Proteins Inhibit Neovascularization and Suppress Tumor Growth in MDA-MB-231 Breast Cancer Xenografts

Directory of Open Access Journals (Sweden)

Jacob E. Koskimaki

2009-12-01

Full Text Available Angiogenesis or neovascularization, the process of new blood vessel formation from preexisting microvasculature, involves interactions among several cell types including parenchymal, endothelial cells, and immune cells. The formation of new vessels is tightly regulated by a balance between endogenous proangiogenic and antiangiogenic factors to maintain homeostasis in tissue; tumor progression and metastasis in breast cancer have been shown to be angiogenesis-dependent. We previously introduced a systematic methodology to identify putative endogenous antiangiogenic peptides and validated these predictions in vitro in human umbilical vein endothelial cell proliferation and migration assays. These peptides are derived from several protein families including type IV collagen, CXC chemokines, and thrombospondin-1 domain-containing proteins. On the basis of the results from the in vitro screening, we have evaluated the ability of one peptide selected from each family named pentastatin-1, chemokinostatin-1, and properdistatin, respectively, to suppress angiogenesis in an MDA-MB-231 human breast cancer orthotopic xenograft model in severe combined immunodeficient mice. Peptides were administered intraperitoneally once per day. We have demonstrated significant suppression of tumor growth in vivo and subsequent reductions in microvascular density, indicating the potential of these peptides as therapeutic agents for breast cancer.

[Influence of anesthesia procedure on malignant tumor outcome].

Science.gov (United States)

Fukui, K; Werner, C; Pestel, G

2012-03-01

Malignant tumors are the second major cause of death in Germany. The essential therapy of operable cancer is surgical removal of primary tumors combined with adjuvant therapy. However, several consequences of surgery may promote metastasis, such as shedding of tumor cells into the circulation, decrease in tumor-induced antiangiogenesis factors, excessive release of growth factors for wound healing and suppression of immunity induced by surgical stress. In the last decade it has become clear that cell-mediated immunity controls the development of metastasis. Various perioperative factors, such as surgical stress, certain anesthetic and analgesic drugs and pain can suppress the patients' immune system perioperatively. On the other hand, by modifications of the anesthesia technique (e.g. regional anesthesia) and perioperative management to minimize immunosuppression, anesthesiologists can play a considerable role for a better outcome in patients having malignant tumors. Sufficient clinical evidence is not yet available to prove or disprove the hypothesis that anesthesia practice can improve cancer prognosis. Despite difficulties in study design, several prospective randomized trials are currently running and the results are awaited to elucidate this topic.

Potent inhibition of tumoral hypoxia-inducible factor 1α by albendazole

International Nuclear Information System (INIS)

Pourgholami, Mohammad H; Cai, Zhao Y; Badar, Samina; Wangoo, Kiran; Poruchynsky, Marianne S; Morris, David L

2010-01-01

Emerging reports suggest resistance, increased tumor invasiveness and metastasis arising from treatment with drugs targeting vascular endothelial growth factor (VEGF). It is believed that increased tumoral hypoxia plays a prominent role in the development of these phenomena. Inhibition of tumoral hypoxia inducible factor (HIF-1α) is thus becoming an increasingly attractive therapeutic target in the treatment of cancer. We hypothesized that the anti-VEGF effect of albendazole (ABZ) could be mediated through inhibition of tumoral HIF-1α. In vitro, the effects of ABZ on HIF-1α levels in human ovarian cancer cells (OVCAR-3) were investigated using hypoxic chamber or desferrioxamine (DFO) induced-hypoxia. In vivo, the effects of ABZ (150 mg/kg, i.p., single dose) on the tumor levels of HIF-1α and VEGF protein and mRNA were investigated by western blotting, RT-PCR and real time-PCR. In vitro, ABZ inhibited cellular HIF-1α protein accumulation resulting from placement of cells under hypoxic chamber or exposure to DFO. In vivo, tumors excised from vehicle treated mice showed high levels of both HIF-1α and VEGF. Whereas, tumoral HIF-1α and VEGF protein levels were highly suppressed in ABZ treated mice. Tumoral VEGFmRNA (but not HIF-1αmRNA) was also found to be highly suppressed by ABZ. These results demonstrate for the first time the effects of an acute dose of ABZ in profoundly suppressing both HIF-1α and VEGF within the tumor. This dual inhibition may provide additional value in inhibiting angiogenesis and be at least partially effective in inhibiting tumoral HIF-1α surge, tumor invasiveness and metastasis

Activated Natural Killer Cells Mediate the Suppressive Effect of Interleukin-4 on Tumor Development via STAT6 Activation in an Atopic Condition Melanoma Model

OpenAIRE

Dong Ju Son; Yu Yeon Jung; Mi Hee Park; Hye Lim Lee; Min Ji Song; Hwan-Soo Yoo; Dae Youn Hwang; Sang Bae Han; Jin Tae Hong

2017-01-01

A protective effect of allergy for cancer has been suggested, but the results are somewhat conflicting, and the mechanism remains elusive. Interleukin-4 (IL-4) signaling has been identified as a potentially important pathway in the development of allergies and the suppression of cancer development. To evaluate the allergy responses in IL-4?mediated tumor development, we compared the growth of B16F10 melanoma cells in 4% phthalic anhydride (PA)-treated IL-4/Luc/CNS-1 transgenic mice (IL-4 mice...

Characterization of TEM1/endosialin in human and murine brain tumors

International Nuclear Information System (INIS)

Carson-Walter, Eleanor B; Walter, Kevin A; Winans, Bethany N; Whiteman, Melissa C; Liu, Yang; Jarvela, Sally; Haapasalo, Hannu; Tyler, Betty M; Huso, David L; Johnson, Mahlon D

2009-01-01

TEM1/endosialin is an emerging microvascular marker of tumor angiogenesis. We characterized the expression pattern of TEM1/endosialin in astrocytic and metastatic brain tumors and investigated its role as a therapeutic target in human endothelial cells and mouse xenograft models. In situ hybridization (ISH), immunohistochemistry (IH) and immunofluorescence (IF) were used to localize TEM1/endosialin expression in grade II-IV astrocytomas and metastatic brain tumors on tissue microarrays. Changes in TEM1/endosialin expression in response to pro-angiogenic conditions were assessed in human endothelial cells grown in vitro. Intracranial U87MG glioblastoma (GBM) xenografts were analyzed in nude TEM1/endosialin knockout (KO) and wildtype (WT) mice. TEM1/endosialin was upregulated in primary and metastatic human brain tumors, where it localized primarily to the tumor vasculature and a subset of tumor stromal cells. Analysis of 275 arrayed grade II-IV astrocytomas demonstrated TEM1/endosialin expression in 79% of tumors. Robust TEM1/endosialin expression occurred in 31% of glioblastomas (grade IV astroctyomas). TEM1/endosialin expression was inversely correlated with patient age. TEM1/endosialin showed limited co-localization with CD31, αSMA and fibronectin in clinical specimens. In vitro, TEM1/endosialin was upregulated in human endothelial cells cultured in matrigel. Vascular Tem1/endosialin was induced in intracranial U87MG GBM xenografts grown in mice. Tem1/endosialin KO vs WT mice demonstrated equivalent survival and tumor growth when implanted with intracranial GBM xenografts, although Tem1/endosialin KO tumors were significantly more vascular than the WT counterparts. TEM1/endosialin was induced in the vasculature of high-grade brain tumors where its expression was inversely correlated with patient age. Although lack of TEM1/endosialin did not suppress growth of intracranial GBM xenografts, it did increase tumor vascularity. The cellular localization of TEM1

Tumor suppression effects of bilberry extracts and enzymatically modified isoquercitrin in early preneoplastic liver cell lesions induced by piperonyl butoxide promotion in a two-stage rat hepatocarcinogenesis model.

Science.gov (United States)

Hara, Shintaro; Morita, Reiko; Ogawa, Takashi; Segawa, Risa; Takimoto, Norifumi; Suzuki, Kazuhiko; Hamadate, Naobumi; Hayashi, Shim-Mo; Odachi, Ayano; Ogiwara, Isao; Shibusawa, Sakae; Yoshida, Toshinori; Shibutani, Makoto

2014-08-01

To investigate the protective effect of bilberry extracts (BBE) and enzymatically modified isoquercitrin (EMIQ) on the hepatocarcinogenic process involving oxidative stress responses, we used a two-stage hepatocarcinogenesis model in N-diethylnitrosamine-initiated and piperonyl butoxide (PBO)-promoted rats. We examined the modifying effect of co-administration with BBE or EMIQ on the liver tissue environment including oxidative stress responses, cell proliferation and apoptosis, and phosphatase and tensin homolog (PTEN)/Akt and transforming growth factor (TGF)-β/Smad signalings on the induction mechanism of preneoplastic lesions during early stages of hepatocellular tumor promotion. PBO increased the numbers and area of glutathione S-transferase placental form (GST-P)(+) liver cell foci and the numbers of Ki-67(+) proliferating cells within GST-P(+) foci. Co-administration of BBE or EMIQ suppressed these effects with the reductions of GST-P(+) foci (area) to 48.9-49.4% and Ki-67(+) cells to 55.5-61.4% of the PBO-promoted cases. Neither BBE nor EMIQ decreased microsomal reactive oxygen species induced by PBO. However, only EMIQ suppressed the level of thiobarbituric acid-reactive substances to 78.4% of the PBO-promoted cases. PBO increased the incidences of phospho-PTEN(-) foci, phospho-Akt substrate(+) foci, phospho-Smad3(-) foci and Smad4(-) foci in GST-P(+) foci. Both BBE and EMIQ decreased the incidences of phospho-PTEN(-) foci in GST-P(+) foci to 59.8-72.2% and Smad4(-) foci to 62.4-71.5% of the PBO-promoted cases, and BBE also suppressed the incidence of phospho-Akt substrate(+) foci in GST-P(+) foci to 75.2-75.7% of the PBO-promoted cases. These results suggest that PBO-induced tumor promotion involves facilitation of PTEN/Akt and disruptive TGF-β/Smad signalings without relation to oxidative stress responses, but this promotion was suppressed by co-treatment with BBE or EMIQ through suppression of cell proliferation activity of preneoplastic liver cells

An HRE-Binding Py-Im Polyamide Impairs Hypoxic Signaling in Tumors.

Science.gov (United States)

Szablowski, Jerzy O; Raskatov, Jevgenij A; Dervan, Peter B

2016-04-01

Hypoxic gene expression contributes to the pathogenesis of many diseases, including organ fibrosis, age-related macular degeneration, and cancer. Hypoxia-inducible factor-1 (HIF1), a transcription factor central to the hypoxic gene expression, mediates multiple processes including neovascularization, cancer metastasis, and cell survival. Pyrrole-imidazole polyamide 1: has been shown to inhibit HIF1-mediated gene expression in cell culture but its activity in vivo was unknown. This study reports activity of polyamide 1: in subcutaneous tumors capable of mounting a hypoxic response and showing neovascularization. We show that 1: distributes into subcutaneous tumor xenografts and normal tissues, reduces the expression of proangiogenic and prometastatic factors, inhibits the formation of new tumor blood vessels, and suppresses tumor growth. Tumors treated with 1: show no increase in HIF1α and have reduced ability to adapt to the hypoxic conditions, as evidenced by increased apoptosis in HIF1α-positive regions and the increased proximity of necrotic regions to vasculature. Overall, these results show that a molecule designed to block the transcriptional activity of HIF1 has potent antitumor activity in vivo, consistent with partial inhibition of the tumor hypoxic response. Mol Cancer Ther; 15(4); 608-17. ©2015 AACR. ©2015 American Association for Cancer Research.

Histological type and grade of breast cancer tumors by parity, age at birth, and time since birth: a register-based study in Norway

Directory of Open Access Journals (Sweden)

Heuch Ivar

2010-05-01

Full Text Available Abstract Background Some studies have indicated that reproductive factors affect the risk of histological types of breast cancer differently. The long-term protective effect of a childbirth is preceded by a short-term adverse effect. Few studies have examined whether tumors diagnosed shortly after birth have specific histological characteristics. Methods In the present register-based study, comprising information for 22,867 Norwegian breast cancer cases (20-74 years, we examined whether histological type (9 categories and grade of tumor (2 combined categories differed by parity or age at first birth. Associations with time since birth were evaluated among 9709 women diagnosed before age 50 years. Chi-square tests were applied for comparing proportions, whereas odds ratios (each histological type vs. ductal, or grade 3-4 vs. grade 1-2 were estimated in polytomous and binary logistic regression analyses. Results Ductal tumors, the most common histological type, accounted for 81.4% of all cases, followed by lobular tumors (6.3% and unspecified carcinomas (5.5%. Other subtypes accounted for 0.4%-1.5% of the cases each. For all histological types, the proportions differed significantly by age at diagnoses. The proportion of mucinous and tubular tumors decreased with increasing parity, whereas Paget disease and medullary tumors were most common in women of high parity. An increasing trend with increasing age at first birth was most pronounced for lobular tumors and unspecified carcinomas; an association in the opposite direction was seen in relation to medullary and tubular tumors. In age-adjusted analyses, only the proportions of unspecified carcinomas and lobular tumors decreased significantly with increasing time since first and last birth. However, ductal tumors, and malignant sarcomas, mainly phyllodes tumors, seemed to occur at higher frequency in women diagnosed Conclusion Our results support previous observations that reproductive factors

Fractional laser exposure induces neutrophil infiltration (N1 phenotype into the tumor and stimulates systemic anti-tumor immune response.

Directory of Open Access Journals (Sweden)

Masayoshi Kawakubo

Full Text Available Ablative fractional photothermolysis (aFP using a CO2 laser generates multiple small diameter tissue lesions within the irradiation field. aFP is commonly used for a wide variety of dermatological indications, including treatment of photodamaged skin and dyschromia, drug delivery and modification of scars due to acne, surgical procedures and burns. In this study we explore the utility of aFP for treating oncological indications, including induction of local tumor regression and inducing anti-tumor immunity, which is in marked contrast to current indications of aFP.We used a fractional CO2 laser to treat a tumor established by BALB/c colon carcinoma cell line (CT26.CL25, which expressed a tumor antigen, beta-galactosidase (beta-gal. aFP treated tumors grew significantly slower as compared to untreated controls. Complete remission after a single aFP treatment was observed in 47% of the mice. All survival mice from the tumor inoculation rejected re-inoculation of the CT26.CL25 colon carcinoma cells and moreover 80% of the survival mice rejected CT26 wild type colon carcinoma cells, which are parental cells of CT26.CL25 cells. Histologic section of the FP-treated tumors showed infiltrating neutrophil in the tumor early after aFP treatment. Flow cytometric analysis of tumor-infiltrating lymphocytes showed aFP treatment abrogated the increase in regulatory T lymphocyte (Treg, which suppresses anti-tumor immunity and elicited the expansion of epitope-specific CD8+ T lymphocytes, which were required to mediate the tumor-suppressing effect of aFP.We have demonstrated that aFP is able to induce a systemic anti-tumor adaptive immunity preventing tumor recurrence in a murine colon carcinoma in a mouse model. This study demonstrates a potential role of aFP treatments in oncology and further studies should be performed.

Tumor-reactive immune cells protect against metastatic tumor and induce immunoediting of indolent but not quiescent tumor cells.

Science.gov (United States)

Payne, Kyle K; Keim, Rebecca C; Graham, Laura; Idowu, Michael O; Wan, Wen; Wang, Xiang-Yang; Toor, Amir A; Bear, Harry D; Manjili, Masoud H

2016-09-01

Two major barriers to cancer immunotherapy include tumor-induced immune suppression mediated by myeloid-derived suppressor cells and poor immunogenicity of the tumor-expressing self-antigens. To overcome these barriers, we reprogrammed tumor-immune cell cross-talk by combined use of decitabine and adoptive immunotherapy, containing tumor-sensitized T cells and CD25(+) NKT cells. Decitabine functioned to induce the expression of highly immunogenic cancer testis antigens in the tumor, while also reducing the frequency of myeloid-derived suppressor cells and the presence of CD25(+) NKT cells rendered T cells, resistant to remaining myeloid-derived suppressor cells. This combinatorial therapy significantly prolonged survival of animals bearing metastatic tumor cells. Adoptive immunotherapy also induced tumor immunoediting, resulting in tumor escape and associated disease-related mortality. To identify a tumor target that is incapable of escape from the immune response, we used dormant tumor cells. We used Adriamycin chemotherapy or radiation therapy, which simultaneously induce tumor cell death and tumor dormancy. Resultant dormant cells became refractory to additional doses of Adriamycin or radiation therapy, but they remained sensitive to tumor-reactive immune cells. Importantly, we discovered that dormant tumor cells contained indolent cells that expressed low levels of Ki67 and quiescent cells that were Ki67 negative. Whereas the former were prone to tumor immunoediting and escape, the latter did not demonstrate immunoediting. Our results suggest that immunotherapy could be highly effective against quiescent dormant tumor cells. The challenge is to develop combinatorial therapies that could establish a quiescent type of tumor dormancy, which would be the best target for immunotherapy. © The Author(s).

A reason for intermittent fasting to suppress the awakening of dormant breast tumors.

Science.gov (United States)

Lankelma, Jan; Kooi, Bob; Krab, Klaas; Dorsman, Josephine C; Joenje, Hans; Westerhoff, Hans V

2015-01-01

For their growth, dormant tumors, which lack angiogenesis may critically depend on gradients of nutrients and oxygen from the nearest blood vessel. Because for oxygen depletion the distance from the nearest blood vessel to depletion will generally be shorter than for glucose depletion, such tumors will contain anoxic living tumor cells. These cells are dangerous, because they are capable of inducing angiogenesis, which will "wake up" the tumor. Anoxic cells are dependent on anaerobic glucose breakdown for ATP generation. The local extracellular glucose concentration gradient is determined by the blood glucose concentration and by consumption by cells closer to the nearest blood vessel. The blood glucose concentration can be lowered by 20-40% during fasting. We calculated that glucose supply to the potentially hazardous anoxic cells can thereby be reduced significantly, resulting in cell death specifically of the anoxic tumor cells. We hypothesize that intermittent fasting will help to reduce the incidence of tumor relapse via reducing the number of anoxic tumor cells and tumor awakening. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Tumor-altered dendritic cell function: implications for anti-tumor immunity

Directory of Open Access Journals (Sweden)

Kristian Michael Hargadon

2013-07-01

Full Text Available Dendritic cells are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programming of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti-tumor

Platelets promote tumor growth and metastasis via direct interaction between Aggrus/podoplanin and CLEC-2.

Directory of Open Access Journals (Sweden)

Satoshi Takagi

Full Text Available The platelet aggregation-inducing factor Aggrus, also known as podoplanin, is frequently upregulated in several types of tumors and enhances hematogenous metastasis by interacting with and activating the platelet receptor CLEC-2. Thus, Aggrus-CLEC-2 binding could be a therapeutic molecular mechanism for cancer therapy. We generated a new anti-human Aggrus monoclonal antibody, MS-1, that suppressed Aggrus-CLEC-2 binding, Aggrus-induced platelet aggregation, and Aggrus-mediated tumor metastasis. Interestingly, the MS-1 monoclonal antibody attenuated the growth of Aggrus-positive tumors in vivo. Moreover, the humanized chimeric MS-1 antibody, ChMS-1, also exhibited strong antitumor activity against Aggrus-positive lung squamous cell carcinoma xenografted into NOD-SCID mice compromising antibody-dependent cellular cytotoxic and complement-dependent cytotoxic activities. Because Aggrus knockdown suppressed platelet-induced proliferation in vitro and tumor growth of the lung squamous cell carcinoma in vivo, Aggrus may be involved in not only tumor metastasis but also tumor growth by promoting platelet-tumor interaction, platelet activation, and secretion of platelet-derived factors in vivo. Our results indicate that molecular target drugs inhibiting specific platelet-tumor interactions can be developed as antitumor drugs that suppress both metastasis and proliferation of tumors such as lung squamous cell carcinoma.

Activation of α7nAChR Promotes Diabetic Wound Healing by Suppressing AGE-Induced TNF-α Production.

Science.gov (United States)

Dong, Miao-Wu; Li, Ming; Chen, Jie; Fu, Tong-Tong; Lin, Ke-Zhi; Ye, Guang-Hua; Han, Jun-Ge; Feng, Xiang-Ping; Li, Xing-Biao; Yu, Lin-Sheng; Fan, Yan-Yan

2016-04-01

Diabetes frequently presents accumulation of advanced glycation end products (AGEs), which might induce excessive TNF-α production from macrophages to cause impaired wound healing. Recent studies have shown that activation of α7 nicotinic acetylcholine receptor (α7nAChR) on macrophages efficiently suppressed TNF-α synthesis. The aim of this study was to investigate the accumulation of AGEs in the wounds and determine whether PNU282987, an α7nAChR agonist, can improve wound repair by inhibiting AGE-mediated TNF-α production in a streptozotocin (STZ)-induced diabetic mouse model. Animals were assigned into four groups: wounded control group, wounded diabetic group, wounded diabetic group treated intraperitoneally with PNU282987, or wounded diabetic group treated intraperitoneally with vehicle. Compared with the non-diabetic control mice, the diabetic mice exhibited delayed wound healing that was characterized by elevated accumulation of AGEs, increased TNF-α level and macrophage infiltration, and decreased fibroblast number and collagen deposition at the late stage of repair. Besides, macrophages of diabetic wounds showed expression of α7nAChR. During late repair, PNU282987 treatment of diabetic mice significantly reduced the level of TNF-α, accelerated wound healing, and elevated fibroblast number and collagen deposition. To investigate the cellular mechanism of these observations, RAW 264.7 cells, a macrophage cell line, were incubated with AGEs in the presence or absence of PNU282987. TNF-α production from AGE-stimulated macrophages was significantly decreased by PNU282987 in a dose-dependent manner. Furthermore, PNU282987 significantly inhibited AGE-induced nuclear factor-κB (NF-κB) activation and receptor for AGE (RAGE) expression. These results strongly suggest that activating α7nAChR can promote diabetic wound healing by suppressing AGE-induced TNF-α production, which may be closely associated with the blockage of NF-κB activation in macrophages.

Cancer associated fibroblasts promote tumor growth and metastasis by modulating the tumor immune microenvironment in a 4T1 murine breast cancer model.

Directory of Open Access Journals (Sweden)

Debbie Liao

2009-11-01

Full Text Available Local inflammation associated with solid tumors commonly results from factors released by tumor cells and the tumor stroma, and promotes tumor progression. Cancer associated fibroblasts comprise a majority of the cells found in tumor stroma and are appealing targets for cancer therapy. Here, our aim was to determine the efficacy of targeting cancer associated fibroblasts for the treatment of metastatic breast cancer.We demonstrate that cancer associated fibroblasts are key modulators of immune polarization in the tumor microenvironment of a 4T1 murine model of metastatic breast cancer. Elimination of cancer associated fibroblasts in vivo by a DNA vaccine targeted to fibroblast activation protein results in a shift of the immune microenvironment from a Th2 to Th1 polarization. This shift is characterized by increased protein expression of IL-2 and IL-7, suppressed recruitment of tumor-associated macrophages, myeloid derived suppressor cells, T regulatory cells, and decreased tumor angiogenesis and lymphangiogenesis. Additionally, the vaccine improved anti-metastatic effects of doxorubicin chemotherapy and enhanced suppression of IL-6 and IL-4 protein expression while increasing recruitment of dendritic cells and CD8(+ T cells. Treatment with the combination therapy also reduced tumor-associated Vegf, Pdgfc, and GM-CSF mRNA and protein expression.Our findings demonstrate that cancer associated fibroblasts promote tumor growth and metastasis through their role as key modulators of immune polarization in the tumor microenvironment and are valid targets for therapy of metastatic breast cancer.

Cancer associated fibroblasts promote tumor growth and metastasis by modulating the tumor immune microenvironment in a 4T1 murine breast cancer model.

Science.gov (United States)

Liao, Debbie; Luo, Yunping; Markowitz, Dorothy; Xiang, Rong; Reisfeld, Ralph A

2009-11-23

Local inflammation associated with solid tumors commonly results from factors released by tumor cells and the tumor stroma, and promotes tumor progression. Cancer associated fibroblasts comprise a majority of the cells found in tumor stroma and are appealing targets for cancer therapy. Here, our aim was to determine the efficacy of targeting cancer associated fibroblasts for the treatment of metastatic breast cancer. We demonstrate that cancer associated fibroblasts are key modulators of immune polarization in the tumor microenvironment of a 4T1 murine model of metastatic breast cancer. Elimination of cancer associated fibroblasts in vivo by a DNA vaccine targeted to fibroblast activation protein results in a shift of the immune microenvironment from a Th2 to Th1 polarization. This shift is characterized by increased protein expression of IL-2 and IL-7, suppressed recruitment of tumor-associated macrophages, myeloid derived suppressor cells, T regulatory cells, and decreased tumor angiogenesis and lymphangiogenesis. Additionally, the vaccine improved anti-metastatic effects of doxorubicin chemotherapy and enhanced suppression of IL-6 and IL-4 protein expression while increasing recruitment of dendritic cells and CD8(+) T cells. Treatment with the combination therapy also reduced tumor-associated Vegf, Pdgfc, and GM-CSF mRNA and protein expression. Our findings demonstrate that cancer associated fibroblasts promote tumor growth and metastasis through their role as key modulators of immune polarization in the tumor microenvironment and are valid targets for therapy of metastatic breast cancer.

The regional extent of suppression: strabismics versus nonstrabismics.

Science.gov (United States)

Babu, Raiju Jacob; Clavagnier, Simon R; Bobier, William; Thompson, Benjamin; Hess, Robert F

2013-10-09

Evidence is accumulating that suppression may be the cause of amblyopia rather than a secondary consequence of mismatched retinal images. For example, treatment interventions that target suppression may lead to better binocular and monocular outcomes. Furthermore, it has recently been demonstrated that the measurement of suppression may have prognostic value for patching therapy. For these reasons, the measurement of suppression in the clinic needs to be improved beyond the methods that are currently available, which provide a binary outcome. We describe a novel quantitative method for measuring the regional extent of suppression that is suitable for clinical use. The method involves a dichoptic perceptual matching procedure at multiple visual field locations. We compare a group of normal controls (mean age: 28 ± 5 years); a group with strabismic amblyopia (four with microesotropia, five with esotropia, and one with exotropia; mean age: 35 ± 10 years); and a group with nonstrabismic anisometropic amblyopia (mean age: 33 ± 12 years). The extent and magnitude of suppression was similar for observers with strabismic and nonstrabismic amblyopia. Suppression was strongest within the central field and extended throughout the 20° field that we measured. Suppression extends throughout the central visual field in both strabismic and anisometropic forms of amblyopia. The strongest suppression occurs within the region of the visual field corresponding to the fovea of the fixing eye.

Use of Aromatase Inhibitors in Large Cell Calcifying Sertoli Cell Tumors: Effects on Gynecomastia, Growth Velocity, and Bone Age

Science.gov (United States)

Crocker, Melissa K.; Gourgari, Evgenia; Stratakis, Constantine A.

2014-01-01

Context: Large cell calcifying Sertoli cell tumors (LCCSCT) present in isolation or, especially in children, in association with Carney Complex (CNC) or Peutz-Jeghers Syndrome (PJS). These tumors overexpress aromatase (CYP19A1), which leads to increased conversion of delta-4-androstenedione to estrone and testosterone to estradiol. Prepubertal boys may present with growth acceleration, advanced bone age, and gynecomastia. Objective: To investigate the outcomes of aromatase inhibitor therapy (AIT) in prepubertal boys with LCCSCTs. Design: Case series of a very rare tumor and chart review of cases treated at other institutions. Setting: Tertiary care and referral center. Patients: Six boys, five with PJS and one with CNC, were referred to the National Institutes of Health for treatment of LCCSCT. All patients had gynecomastia, testicular enlargement, and advanced bone ages, and were being treated by their referring physicians with AIT. Interventions: Patients were treated for a total of 6–60 months on AIT. Main Outcome Measures: Height, breast tissue mass, and testicular size were all followed; physical examination, scrotal ultrasounds, and bone ages were obtained, and hormonal concentrations and tumor markers were measured. Results: Tumor markers were negative. All patients had decreases in breast tissue while on therapy. Height percentiles declined, and predicted adult height moved closer to midparental height as bone age advancement slowed. Testicular enlargement stabilized until entry into central puberty. Only one patient required unilateral orchiectomy. Conclusions: Patients with LCCSCT benefit from AIT with reduction and/or elimination of gynecomastia and slowing of linear growth and bone age advancement. Further study of long-term outcomes and safety monitoring are needed but these preliminary data suggest that mammoplasty and/or orchiectomy may be foregone in light of the availability of medical therapy. PMID:25226294

Age- and Tumor Subtype-Specific Breast Cancer Risk Estimates for CHEK2*1100delC Carriers

DEFF Research Database (Denmark)

Schmidt, Marjanka K; Hogervorst, Frans; van Hien, Richard R

2016-01-01

PURPOSE: CHEK2*1100delC is a well-established breast cancer risk variant that is most prevalent in European populations; however, there are limited data on risk of breast cancer by age and tumor subtype, which limits its usefulness in breast cancer risk prediction. We aimed to generate tumor...... subtype- and age-specific risk estimates by using data from the Breast Cancer Association Consortium, including 44,777 patients with breast cancer and 42,997 controls from 33 studies genotyped for CHEK2*1100delC. PATIENTS AND METHODS: CHEK2*1100delC genotyping was mostly done by a custom Taqman assay....... Breast cancer odds ratios (ORs) for CHEK2*1100delC carriers versus noncarriers were estimated by using logistic regression and adjusted for study (categorical) and age. Main analyses included patients with invasive breast cancer from population- and hospital-based studies. RESULTS: Proportions...

Stereotactic body radiotherapy for stage I lung cancer and small lung metastasis: evaluation of an immobilization system for suppression of respiratory tumor movement and preliminary results

Directory of Open Access Journals (Sweden)

Ayakawa Shiho

2009-05-01

Full Text Available Abstract Background In stereotactic body radiotherapy (SBRT for lung tumors, reducing tumor movement is necessary. In this study, we evaluated changes in tumor movement and percutaneous oxygen saturation (SpO2 levels, and preliminary clinical results of SBRT using the BodyFIX immobilization system. Methods Between 2004 and 2006, 53 consecutive patients were treated for 55 lesions; 42 were stage I non-small cell lung cancer (NSCLC, 10 were metastatic lung cancers, and 3 were local recurrences of NSCLC. Tumor movement was measured with fluoroscopy under breath holding, free breathing on a couch, and free breathing in the BodyFIX system. SpO2 levels were measured with a finger pulseoximeter under each condition. The delivered dose was 44, 48 or 52 Gy, depending on tumor diameter, in 4 fractions over 10 or 11 days. Results By using the BodyFIX system, respiratory tumor movements were significantly reduced compared with the free-breathing condition in both craniocaudal and lateral directions, although the amplitude of reduction in the craniocaudal direction was 3 mm or more in only 27% of the patients. The average SpO2 did not decrease by using the system. At 3 years, the local control rate was 80% for all lesions. Overall survival was 76%, cause-specific survival was 92%, and local progression-free survival was 76% at 3 years in primary NSCLC patients. Grade 2 radiation pneumonitis developed in 7 patients. Conclusion Respiratory tumor movement was modestly suppressed by the BodyFIX system, while the SpO2 level did not decrease. It was considered a simple and effective method for SBRT of lung tumors. Preliminary results were encouraging.

Natural Compounds Regulate Glycolysis in Hypoxic Tumor Microenvironment

Directory of Open Access Journals (Sweden)

Jian-Li Gao

2015-01-01

Full Text Available In the early twentieth century, Otto Heinrich Warburg described an elevated rate of glycolysis occurring in cancer cells, even in the presence of atmospheric oxygen (the Warburg effect. Recently it became a therapeutically interesting strategy and is considered as an emerging hallmark of cancer. Hypoxia inducible factor-1 (HIF-1 is one of the key transcription factors that play major roles in tumor glycolysis and could directly trigger Warburg effect. Thus, how to inhibit HIF-1-depended Warburg effect to assist the cancer therapy is becoming a hot issue in cancer research. In fact, HIF-1 upregulates the glucose transporters (GLUT and induces the expression of glycolytic enzymes, such as hexokinase, pyruvate kinase, and lactate dehydrogenase. So small molecules of natural origin used as GLUT, hexokinase, or pyruvate kinase isoform M2 inhibitors could represent a major challenge in the field of cancer treatment. These compounds aim to suppress tumor hypoxia induced glycolysis process to suppress the cell energy metabolism or enhance the susceptibility of tumor cells to radio- and chemotherapy. In this review, we highlight the role of natural compounds in regulating tumor glycolysis, with a main focus on the glycolysis under hypoxic tumor microenvironment.

VEGF-dependent mechanism of anti-angiogenic action of diamond nanoparticles in Glioblastoma Multiforme tumor

DEFF Research Database (Denmark)

Grodzik, M.; Sawosz, E.; Wierzbicki, M.

2012-01-01

Malignant gliomas are highly lethal cancers dependent on angiogenesis. The concept of treating tumors by inhibiting tumor angiogenesis was first articulated almost 30 years ago. Inhibition of tumor angiogenesis suppresses both tumor growth and metastasis. We determined the inhibition effect of di...

Dutasteride and enzalutamide synergistically suppress prostate tumor cell proliferation

NARCIS (Netherlands)

Hamid, A.R.; Verhaegh, G.W.C.T.; Smit, F.P.; RIjt-van de Westerlo, C.; Armandari, I.; Brandt, A.; Sweep, F.C.; Sedelaar, J.P.M.; Schalken, J.A.

2015-01-01

PURPOSE: Dihydrotestosterone is the main active androgen in the prostate and it has a role in prostate cancer progression. After androgen deprivation therapy androgen receptor signaling is still active in tumor cells. Persistent intratumor steroidogenesis and androgen receptor changes are

4-Acetylantroquinonol B inhibits colorectal cancer tumorigenesis and suppresses cancer stem-like phenotype

Energy Technology Data Exchange (ETDEWEB)

Chang, Tung-Cheng [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Department of Surgery, Taipei Medical University-Shuang Ho Hospital, New Taipei City 23561, Taiwan (China); Yeh, Chi-Tai [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Department of Surgery, Taipei Medical University-Shuang Ho Hospital, New Taipei City 23561, Taiwan (China); Department of Medical Research and Education, Taipei Medical University-Shuang Ho Hospital, New Taipei City 23561, Taiwan (China); Adebayo, Bamodu Oluwaseun [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Department of Medical Research and Education, Taipei Medical University-Shuang Ho Hospital, New Taipei City 23561, Taiwan (China); Lin, Ying-Chin [Department of Family Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan (China); Department of Family Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Deng, Li [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China); Amoy-BUCT Industrial Bio-technovation Institute, Amoy 361022 (China); Rao, Yerra Koteswara; Huang, Chun-Chih [Institute of Biochemical Sciences and Technology, Chaoyang University of Technology, Taichung 41349, Taiwan (China); Lee, Wei-Hwa [Department of Pathology, Taipei Medical University-Shuang Ho Hospital, New Taipei City 23561, Taiwan (China); Wu, Alexander T.H. [Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan (China); Hsiao, Michael [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China); and others

2015-10-15

4-Acetylantroquinonol B (4-AAQB), closely related to the better known antroquinonol, is a bioactive isolate of the mycelia of Antrodia camphorata, a Taiwanese mushroom with documented anti-inflammatory, hypoglycemic, vasorelaxative, and recently demonstrated, antiproliferative activity. Based on its traditional use, we hypothesized that 4-AAQB may play an active role in the suppression of cellular transformation, tumor aggression and progression, as well as chemoresistance in colorectal carcinoma (CRC). In this study, we investigated the antiproliferative role of 4-AAQB and its underlying molecular mechanism. We also compared its anticancer therapeutic potential with that of antroquinonol and the CRC combination chemotherapy of choice — folinic acid, fluorouracil and oxaliplatin (FOLFOX). Our results showed that 4-AAQB was most effective in inhibiting tumor proliferation, suppressing tumor growth and attenuating stemness-related chemoresistance. 4-AAQB negatively regulates vital oncogenic and stem cell maintenance signal transduction pathways, including the Lgr5/Wnt/β-catenin, JAK–STAT, and non-transmembrane receptor tyrosine kinase signaling pathways, as well as inducing a dose-dependent downregulation of ALDH and other stemness related factors. These results were validated in vivo, with animal studies showing 4-AAQB possessed comparable tumor-shrinking ability as FOLFOX and potentiates ability of the later to reduce tumor size. Thus, 4-AAQB, a novel small molecule, projects as a potent therapeutic agent for monotherapy or as a component of standard combination chemotherapy. - Highlights: • 4-Acetylantroquinonol B (4-AAQB) suppressed tumor cell proliferation. • 4-AAQB regulates oncogenic and stem cell maintenance signal pathways. • 4-AAQB negatively regulates Lgr5/Wnt/β-catenin and JAK–STAT pathways. • 4-AAQB reduced ALDH and other stemness related factor expression. • In vivo, 4-AAQB has comparable tumor-shrinking ability as FOLFOX.

4-Acetylantroquinonol B inhibits colorectal cancer tumorigenesis and suppresses cancer stem-like phenotype

International Nuclear Information System (INIS)

Chang, Tung-Cheng; Yeh, Chi-Tai; Adebayo, Bamodu Oluwaseun; Lin, Ying-Chin; Deng, Li; Rao, Yerra Koteswara; Huang, Chun-Chih; Lee, Wei-Hwa; Wu, Alexander T.H.; Hsiao, Michael

2015-01-01

4-Acetylantroquinonol B (4-AAQB), closely related to the better known antroquinonol, is a bioactive isolate of the mycelia of Antrodia camphorata, a Taiwanese mushroom with documented anti-inflammatory, hypoglycemic, vasorelaxative, and recently demonstrated, antiproliferative activity. Based on its traditional use, we hypothesized that 4-AAQB may play an active role in the suppression of cellular transformation, tumor aggression and progression, as well as chemoresistance in colorectal carcinoma (CRC). In this study, we investigated the antiproliferative role of 4-AAQB and its underlying molecular mechanism. We also compared its anticancer therapeutic potential with that of antroquinonol and the CRC combination chemotherapy of choice — folinic acid, fluorouracil and oxaliplatin (FOLFOX). Our results showed that 4-AAQB was most effective in inhibiting tumor proliferation, suppressing tumor growth and attenuating stemness-related chemoresistance. 4-AAQB negatively regulates vital oncogenic and stem cell maintenance signal transduction pathways, including the Lgr5/Wnt/β-catenin, JAK–STAT, and non-transmembrane receptor tyrosine kinase signaling pathways, as well as inducing a dose-dependent downregulation of ALDH and other stemness related factors. These results were validated in vivo, with animal studies showing 4-AAQB possessed comparable tumor-shrinking ability as FOLFOX and potentiates ability of the later to reduce tumor size. Thus, 4-AAQB, a novel small molecule, projects as a potent therapeutic agent for monotherapy or as a component of standard combination chemotherapy. - Highlights: • 4-Acetylantroquinonol B (4-AAQB) suppressed tumor cell proliferation. • 4-AAQB regulates oncogenic and stem cell maintenance signal pathways. • 4-AAQB negatively regulates Lgr5/Wnt/β-catenin and JAK–STAT pathways. • 4-AAQB reduced ALDH and other stemness related factor expression. • In vivo, 4-AAQB has comparable tumor-shrinking ability as FOLFOX.

Differential expression of miR-1, a putative tumor suppressing microRNA, in cancer resistant and cancer susceptible mice

Directory of Open Access Journals (Sweden)

Jessica L. Fleming

2013-04-01

Full Text Available Mus spretus mice are highly resistant to several types of cancer compared to Mus musculus mice. To determine whether differences in microRNA (miRNA expression account for some of the differences in observed skin cancer susceptibility between the strains, we performed miRNA expression profiling of skin RNA for over 300 miRNAs. Five miRNAs, miR-1, miR-124a-3, miR-133a, miR-134, miR-206, were differentially expressed by array and/or qPCR. miR-1 was previously shown to have tumor suppressing abilities in multiple tumor types. We found miR-1 expression to be lower in mouse cutaneous squamous cell carcinomas (cSCCs compared to normal skin. Based on the literature and our expression data, we performed detailed studies on predicted miR-1 targets and evaluated the effect of miR-1 expression on two murine cSCC cell lines, A5 and B9. Following transfection of miR-1, we found decreased mRNA expression of three validated miR-1 targets, Met, Twf1 and Ets1 and one novel target Bag4. Decreased expression of Ets1 was confirmed by Western analysis and by 3’ reporter luciferase assays containing wildtype and mutated Ets1 3’UTR. We evaluated the effect of miR-1 on multiple tumor phenotypes including apoptosis, proliferation, cell cycle and migration. In A5 cells, expression of miR-1 led to decreased proliferation compared to a control miR. miR-1 expression also led to increased apoptosis at later time points (72 and 96 h and to a decrease in cells in S-phase. In summary, we identified five miRNAs with differential expression between cancer resistant and cancer susceptible mice and found that miR-1, a candidate tumor suppressor, has targets with defined roles in tumorigenesis.

Chemical peeling by SA-PEG remodels photo-damaged skin: suppressing p53 expression and normalizing keratinocyte differentiation.

Science.gov (United States)

Dainichi, Teruki; Amano, Satoshi; Matsunaga, Yukiko; Iriyama, Shunsuke; Hirao, Tetsuji; Hariya, Takeshi; Hibino, Toshihiko; Katagiri, Chika; Takahashi, Motoji; Ueda, Setsuko; Furue, Masutaka

2006-02-01

Chemical peeling with salicylic acid in polyethylene glycol vehicle (SA-PEG), which specifically acts on the stratum corneum, suppresses the development of skin tumors in UVB-irradiated hairless mice. To elucidate the mechanism through which chemical peeling with SA-PEG suppresses skin tumor development, the effects of chemical peeling on photodamaged keratinocytes and cornified envelopes (CEs) were evaluated in vivo. Among UVB-irradiated hairless mice, the structural atypia and expression of p53 protein in keratinocytes induced by UVB irradiation were intensely suppressed in the SA-PEG-treated mice 28 days after the start of weekly SA-PEG treatments when compared to that in the control UVB-irradiated mice. Incomplete expression of filaggrin and loricrin in keratinocytes from the control mice was also improved in keratinocytes from the SA-PEG-treated mice. In photo-exposed human facial skin, immature CEs were replaced with mature CEs 4 weeks after treatment with SA-PEG. Restoration of photodamaged stratum corneum by treatment with SA-PEG, which may affect remodeling of the structural environment of the keratinocytes, involved the normalization of keratinocyte differentiation and suppression of skin tumor development. These results suggest that the stratum corneum plays a protective role against carcinogenesis, and provide a novel strategy for the prevention of photo-induced skin tumors.

Twist1 suppresses senescence programs and thereby accelerates and maintains mutant Kras-induced lung tumorigenesis.

Directory of Open Access Journals (Sweden)

Phuoc T Tran

Full Text Available KRAS mutant lung cancers are generally refractory to chemotherapy as well targeted agents. To date, the identification of drugs to therapeutically inhibit K-RAS have been unsuccessful, suggesting that other approaches are required. We demonstrate in both a novel transgenic mutant Kras lung cancer mouse model and in human lung tumors that the inhibition of Twist1 restores a senescence program inducing the loss of a neoplastic phenotype. The Twist1 gene encodes for a transcription factor that is essential during embryogenesis. Twist1 has been suggested to play an important role during tumor progression. However, there is no in vivo evidence that Twist1 plays a role in autochthonous tumorigenesis. Through two novel transgenic mouse models, we show that Twist1 cooperates with Kras(G12D to markedly accelerate lung tumorigenesis by abrogating cellular senescence programs and promoting the progression from benign adenomas to adenocarcinomas. Moreover, the suppression of Twist1 to physiological levels is sufficient to cause Kras mutant lung tumors to undergo senescence and lose their neoplastic features. Finally, we analyzed more than 500 human tumors to demonstrate that TWIST1 is frequently overexpressed in primary human lung tumors. The suppression of TWIST1 in human lung cancer cells also induced cellular senescence. Hence, TWIST1 is a critical regulator of cellular senescence programs, and the suppression of TWIST1 in human tumors may be an effective example of pro-senescence therapy.

Tumor suppressors: enhancers or suppressors of regeneration?

Science.gov (United States)

Pomerantz, Jason H.; Blau, Helen M.

2013-01-01

Tumor suppressors are so named because cancers occur in their absence, but these genes also have important functions in development, metabolism and tissue homeostasis. Here, we discuss known and potential functions of tumor suppressor genes during tissue regeneration, focusing on the evolutionarily conserved tumor suppressors pRb1, p53, Pten and Hippo. We propose that their activity is essential for tissue regeneration. This is in contrast to suggestions that tumor suppression is a trade-off for regenerative capacity. We also hypothesize that certain aspects of tumor suppressor pathways inhibit regenerative processes in mammals, and that transient targeted modification of these pathways could be fruitfully exploited to enhance processes that are important to regenerative medicine. PMID:23715544

Androgen-mediated development of irradiation-induced thyroid tumors in rats: dependence on animal age during interval of androgen replacement in castrated males

International Nuclear Information System (INIS)

Hofmann, C.; Oslapas, R.; Nayyar, R.; Paloyan, E.

1986-01-01

When male Long-Evans rats at age 8 weeks were radiation treated (40 microCi Na131I), thyroid follicular adenomas and carcinomas were observed at age 24 months with a high incidence of 94%. Castration of males prior to irradiation significantly reduced this tumor incidence to 60%. When testosterone (T) was replaced in castrated, irradiated male rats, differentially increased incidences of thyroid tumors occurred. Immediate (age 2-6 mo) or early (age 6-12 mo) T replacement at approximate physiologic levels led to thyroid follicular tumor incidences of 100 and 82%, respectively, whereas intermediate (12-18 mo) or late (18-24 mo) T treatment led to only 70 and 73% incidences, respectively. Continuous T replacement (2-24 mo) in castrated irradiated male rats raised thyroid tumor incidence to 100%. Since elevated thyroid-stimulating hormone (TSH) is a reported requisite for development of radiation-associated thyroid tumors, the effects of T on serum TSH levels were examined. Mean serum TSH values in all irradiated animal groups were significantly elevated above age-matched nonirradiated animals at 6, 12, 18, and 24 months. Serum TSH levels were higher in continuous T-replaced irradiated castrates than in intact, irradiated males, whereas such intact male TSH levels were greater than those for irradiated castrates without T treatment. Interval T replacement in castrated male rats was associated with increased serum TSH levels during the treatment interval and with lowered TSH levels after discontinuation of T treatment, particularly in irradiated rats. However, when irradiated, castrated males received late T replacement (age 18-24 mo), there was no elevation of TSH at the end of the treatment interval. An indirect effect of T via early stimulation of TSH may be partly responsible for the high incidence of irradiation-induced thyroid tumors in rats

Deficiency in Poly(ADP-ribose Polymerase-1 (PARP-1 Accelerates Aging and Spontaneous Carcinogenesis in Mice

Directory of Open Access Journals (Sweden)

Tatiana S. Piskunova

2008-01-01

Full Text Available Genetic and biochemical studies have shown that PARP-1 and poly(ADP-ribosylation play an important role in DNA repair, genomic stability, cell death, inflammation, telomere maintenance, and suppressing tumorigenesis, suggesting that the homeostasis of poly(ADP-ribosylation and PARP-1 may also play an important role in aging. Here we show that PARP-1−/− mice exhibit a reduction of life span and a significant increase of population aging rate. Analysis of noninvasive parameters, including body weight gain, body temperature, estrous function, behavior, and a number of biochemical indices suggests the acceleration of biological aging in PARP-1−/− mice. The incidence of spontaneous tumors in both PARP-1−/− and PARP-1+/+ groups is similar; however, malignant tumors including uterine tumors, lung adenocarcinomas and hepatocellular carcinomas, develop at a significantly higher frequency in PARP-1−/− mice than PARP-1+/+ mice (72% and 49%, resp.; < .05. In addition, spontaneous tumors appear earlier in PARP-1−/− mice compared to the wild type group. Histopathological studies revealed a wide spectrum of tumors in uterus, ovaries, liver, lungs, mammary gland, soft tissues, and lymphoid organs in both groups of the mice. These results demonstrate that inactivation of DNA repair gene PARP-1 in mice leads to acceleration of aging, shortened life span, and increased spontaneous carcinogenesis.

High Concentration of Serum Soluble Fas in Patients with Head and Neck Carcinoma: A Comparative Study Before and After Surgical Removal of Tumor

Directory of Open Access Journals (Sweden)

Seyed Basir Hashemi

2010-01-01

Full Text Available Background:Alternative splicing of the Fas transcript can produce a naturalsecreted isoform of this molecule. Some cancer cells can also produce soluble Fas (sFaswhich may have suppressive effects on the immune system's anti-tumor response.Elevated concentrations of sFas have been detected in the sera of patients with differentmalignancies. Materials and Methods:The concentrations of sFas in sera of patients with headand neck carcinoma (HNC, n=98 and healthy individuals (n=30 were measured bySandwich ELISAand compared to values obtained six months after surgical removalof the tumor (n=48. Data were correlated with different clinical findings of thepatients. Results:sFas concentrations in the sera of HNC patients were found to besignificantly higher in patients with different tumor stages. sFas concentration did notcorrelate with age or tumor invasiveness, however a higher concentration of sFas wasfound in the sera of patients who had higher tumor grades. Surgical removal oftumors in patients resulted in a substantial decrease in sFas concentration.Conclusion:The initial rise in sFas concentration in the sera of HNC patients andits consequent decrease could be regarded as a sign of tumor suppressive mechanisms.Additional studies are needed to fully elucidate this mechanism however these findingsmight show the prospective use of such biomarkers to determine disease prognosis andeven immunotherapeutic applications.

Suppression of Reserve MCM Complexes Chemosensitizes to Gemcitabine and 5-Fluorouracil.

Science.gov (United States)

Bryant, Victoria L; Elias, Roy M; McCarthy, Susan M; Yeatman, Timothy J; Alexandrow, Mark G

2015-09-01

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest forms of cancer and is very difficult to treat with conventional chemotherapeutic regimens. Gemcitabine and 5-fluorouracil are used in the management of PDAC and act by indirectly blocking replicative forks. However, these drugs are not highly effective at suppressing disease progression, indicating a need for the development of innovative therapeutic approaches. Recent studies indicate that suppression of the MCM helicase may provide a novel means to sensitize cancer cells to chemotherapeutic agents that inhibit replicative fork progression. Mammalian cells assemble more MCM complexes on DNA than are required to start S-phase. The excess MCM complexes function as backup initiation sites under conditions of replicative stress. The current study provides definitive evidence that cosuppression of the excess/backup MCM complexes sensitizes PDAC tumor lines to both gemcitabine and 5-FU, leading to increased loss of proliferative capacity compared with drugs alone. This occurs because reduced MCM levels prevent efficient recovery of DNA replication in tumor cells exposed to drug. PDAC tumor cells are more sensitive to MCM loss in the presence of gemcitabine than are nontumor, immortalized epithelial cells. Similarly, colon tumor cells are rendered less viable when cosuppression of MCM complexes occurs during exposure to the crosslinking agent oxaliplatin or topoisomerase inhibitor etoposide. These studies demonstrate that suppressing the backup complement of MCM complexes provides an effective sensitizing approach with the potential to increase the therapeutic index of drugs used in the clinical management of PDAC and other cancers. ©2015 American Association for Cancer Research.

The impact of stress on tumor growth: peripheral CRF mediates tumor-promoting effects of stress

Directory of Open Access Journals (Sweden)

Stathopoulos Efstathios N

2010-09-01

Full Text Available Abstract Introduction Stress has been shown to be a tumor promoting factor. Both clinical and laboratory studies have shown that chronic stress is associated with tumor growth in several types of cancer. Corticotropin Releasing Factor (CRF is the major hypothalamic mediator of stress, but is also expressed in peripheral tissues. Earlier studies have shown that peripheral CRF affects breast cancer cell proliferation and motility. The aim of the present study was to assess the significance of peripheral CRF on tumor growth as a mediator of the response to stress in vivo. Methods For this purpose we used the 4T1 breast cancer cell line in cell culture and in vivo. Cells were treated with CRF in culture and gene specific arrays were performed to identify genes directly affected by CRF and involved in breast cancer cell growth. To assess the impact of peripheral CRF as a stress mediator in tumor growth, Balb/c mice were orthotopically injected with 4T1 cells in the mammary fat pad to induce breast tumors. Mice were subjected to repetitive immobilization stress as a model of chronic stress. To inhibit the action of CRF, the CRF antagonist antalarmin was injected intraperitoneally. Breast tissue samples were histologically analyzed and assessed for neoangiogenesis. Results Array analysis revealed among other genes that CRF induced the expression of SMAD2 and β-catenin, genes involved in breast cancer cell proliferation and cytoskeletal changes associated with metastasis. Cell transfection and luciferase assays confirmed the role of CRF in WNT- β-catenin signaling. CRF induced 4T1 cell proliferation and augmented the TGF-β action on proliferation confirming its impact on TGFβ/SMAD2 signaling. In addition, CRF promoted actin reorganization and cell migration, suggesting a direct tumor-promoting action. Chronic stress augmented tumor growth in 4T1 breast tumor bearing mice and peripheral administration of the CRF antagonist antalarmin suppressed this

Administration of red ginseng ameliorates memory decline in aged mice.

Science.gov (United States)

Lee, Yeonju; Oh, Seikwan

2015-07-01

It has been known that ginseng can be applied as a potential nutraceutical for memory impairment; however, experiments with animals of old age are few. To determine the memory enhancing effect of red ginseng, C57BL/6 mice (21 mo old) were given experimental diet pellets containing 0.12% red ginseng extract (approximately 200 mg/kg/d) for 3 mo. Young and old mice (4 mo and 21 mo old, respectively) were used as the control group. The effect of red ginseng, which ameliorated memory impairment in aged mice, was quantified using Y-maze test, novel objective test, and Morris water maze. Red ginseng ameliorated age-related declines in learning and memory in older mice. In addition, red ginseng's effect on the induction of inducible nitric oxide synthase and proinflammatory cytokines was investigated in the hippocampus of aged mice. Red ginseng treatment suppressed the production of age-processed inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor-α, and interleukin-1β expressions. Moreover, it was observed that red ginseng had an antioxidative effect on aged mice. The suppressed glutathione level in aged mice was restored with red ginseng treatment. The antioxidative-related enzymes Nrf2 and HO-1 were increased with red ginseng treatment. The results revealed that when red ginseng is administered over long periods, age-related decline of learning and memory is ameliorated through anti-inflammatory activity.

miR-216b suppresses breast cancer growth and metastasis by targeting SDCBP

International Nuclear Information System (INIS)

Jana, Samir; Sengupta, Suman; Biswas, Subir; Chatterjee, Annesha; Roy, Himansu; Bhattacharyya, Arindam

2017-01-01

Breast cancer is the most deadly cancer among women and the second leading cause of cancer death worldwide. Treatment effectiveness is complicated with tumor invasiveness/drug resistance. To tailor treatments more effectively to individual patients, it is important to define tumor growth and metastasis at molecular levels. SDCBP is highly overexpressed and associated with a strikingly poor prognosis in breast cancer. However the post transcriptional regulation of SDCBP overexpression remains to be an unexplored area. Our study reveals that miR-216b directly regulates SDCBP expression by binding to its 3′UTR region. miR-216b is a tumor suppressive miRNA and it is underexpressed during metastatic breast cancer. Consequently, overexpression of miR-216b resulted in decreased proliferation, migration and invasion in BC cell lines by modulating the expression of SDCBP. Inhibition of miR-216b divergent the tumor suppressive role by inducing the growth proliferation, migration and invasion in vitro. There is therefore a negative correlation between the expression of miR-216b and its target gene SDCBP in the BC tissue samples as well as cell lines. Simultaneous expression of miR-216b and SDCBP rescued the growth, migration and invasion effect suggesting that tumor suppressive action of miR-216b may be directly mediated by SDCBP. In summary, the study identifies miR-216b as a regulator of SDCBP expression in breast cancer which can potentially be targeted for developing newer therapies for the effective treatment of this killer disease.

Resveratrol Improves Tube Formation in AGE-Induced Late Endothelial Progenitor Cells by Suppressing Syndecan-4 Shedding

Directory of Open Access Journals (Sweden)

Han Wu

2018-01-01

Full Text Available Dysfunction of endothelial progenitor cells (EPCs contributes to cardiovascular complications in diabetes, and resveratrol has been shown to improve EPC functions. Syndecan-4 (Synd4, a cell surface heparin sulfate proteoglycan, has been shown to promote neovascularization. Thus, the present study was performed to determine whether resveratrol promoted angiogenesis of EPCs by regulating Synd4. Late EPCs were isolated from human peripheral blood and stimulated with AGEs. Western blot showed that AGEs induced Synd4 shedding in a dose- and time-dependent manner. AGE-induced Synd4 shedding was partly reversed by NAC or resveratrol, along with normalized ROS production. Overexpression of Synd4 or pretreatment of resveratrol reversed AGE-impaired tube formation of EPCs and regulated the Akt/eNOS pathway. Furthermore, resveratrol suppressed Synd4 shedding via the inhibition of oxidative stress and improved tube formation of late EPCs via the regulation of the Synd4/Akt/eNOS pathway.

Overnight Dexamethasone Suppression Test in the Diagnosis of Cushing's Disease

Directory of Open Access Journals (Sweden)

Fatemeh Esfahanian

2010-08-01

Full Text Available Realizing the cause of Cushing's Syndrome (CS is one of the most challenging processes in clinical endocrinology. The long high dose dexamethasone suppression test (standard test is costly and need an extended inpatient stay. In this study we want to show the clinical utility of the overnight 8 mg dexamethasone suppression test (DST for differential diagnosis of CS in a referral center. Retrospectively from 2002-2005 we selected the patients of endocrinology ward in Imam hospital who were admitted with the diagnosis of Cushing syndrome and had 8 mg DST (modified test along with classic DST. In modified test a decrease in an 8 AM serum cortisol level of 50% or more is thought to indicate suppression and we compared the results of modified test with standard test. This test had been done on 42 patients: 10 male (23% and 32 female (76%. The mean age of patients was 31.39 (15-63, 32 with proven pituitary Cushing's disease, 7 with primary adrnal tumors and 3 with ectopic ACTH syndrome. The standard test according to 50% suppression of UFC had 90.62% sensitivity, and according to 90% suppression had 43.75% sensitivity. The sensitivity of this test was 71.85% for serum cortisol suppression. The modified test (8 mg overnight DST had 78% sensitivity. All of these tests had 100% specificity for the diagnosis of Cushing's disease. The positive predictive vale (PPV of all of these tests was 100%. The negative predictive value (NPV of modified test for the diagnosis of Cushing's disease was 58.82%. In standard test the NPV of serum cortisol was 52.6%, UFC 50% had 76.9% NPV and UFC 90% had 35.7% NPV. The results of serum cortisol suppression in modified test is better than standard test. Although 50% suppression of UFC in standard test had greater sensitivity than modified test, collecting of urine is difficult, time consuming and needing hospitalization, so we advice modified test that is much simpler and more convenient instead of standard test in the first

PTEN C-Terminal Deletion Causes Genomic Instability and Tumor Development

Directory of Open Access Journals (Sweden)

Zhuo Sun

2014-03-01

Full Text Available Tumor suppressor PTEN controls genomic stability and inhibits tumorigenesis. The N-terminal phosphatase domain of PTEN antagonizes the PI3K/AKT pathway, but its C-terminal function is less defined. Here, we describe a knockin mouse model of a nonsense mutation that results in the deletion of the entire Pten C-terminal region, referred to as PtenΔC. Mice heterozygous for PtenΔC develop multiple spontaneous tumors, including cancers and B cell lymphoma. Heterozygous deletion of the Pten C-terminal domain also causes genomic instability and common fragile site rearrangement. We found that Pten C-terminal disruption induces p53 and its downstream targets. Simultaneous depletion of p53 promotes metastasis without influencing the initiation of tumors, suggesting that p53 mainly suppresses tumor progression. Our data highlight the essential role of the PTEN C terminus in the maintenance of genomic stability and suppression of tumorigenesis.

Combination use of lentinan with x-ray therapy in mouse experimental tumor system, (3). Combination effect on the metastatic tumors

Energy Technology Data Exchange (ETDEWEB)

Shiio, Tsuyoshi; Ohishi, Kazuo; Niitsu, Iwayasu; Hayashibara, Hiromi; Tsuchiya, Yoshiharu; Yoshihama, Takashi; Moriyuki, Hirobumi

1988-03-01

Combination effect of lentinan with X-ray irradiation on the metastatic mouse tumors, L1210, KLN205 and Lewis lung carcinoma were studied. Combination use of lentinan with X-ray therapy prolonged the life of BDF/sub 1/ mice bearing L1210 leukemia in the suitable combination conditions. Combination effects of lentinan with X-ray therapy were also observed on the suppression of the growth of KLN205 squamus cell carcinoma and on the suppression of the metastasis of Lewis lung carcinoma. Especially, in the case that lentinan was administered before or after X-ray local irradiation in the pulmorary metastasis system of Lewis lung carcinoma, a marked suppressin of pulmonary metastasis was observed and 2 to 4 mice among 8 tested mice were tumor free.

The SIRT1 deacetylase suppresses intestinal tumorigenesis and colon cancer growth.

Directory of Open Access Journals (Sweden)

Ron Firestein

2008-04-01

Full Text Available Numerous longevity genes have been discovered in model organisms and altering their function results in prolonged lifespan. In mammals, some have speculated that any health benefits derived from manipulating these same pathways might be offset by increased cancer risk on account of their propensity to boost cell survival. The Sir2/SIRT1 family of NAD(+-dependent deacetylases is proposed to underlie the health benefits of calorie restriction (CR, a diet that broadly suppresses cancer in mammals. Here we show that CR induces a two-fold increase SIRT1 expression in the intestine of rodents and that ectopic induction of SIRT1 in a beta-catenin-driven mouse model of colon cancer significantly reduces tumor formation, proliferation, and animal morbidity in the absence of CR. We show that SIRT1 deacetylates beta-catenin and suppresses its ability to activate transcription and drive cell proliferation. Moreover, SIRT1 promotes cytoplasmic localization of the otherwise nuclear-localized oncogenic form of beta-catenin. Consistent with this, a significant inverse correlation was found between the presence of nuclear SIRT1 and the oncogenic form of beta-catenin in 81 human colon tumor specimens analyzed. Taken together, these observations show that SIRT1 suppresses intestinal tumor formation in vivo and raise the prospect that therapies targeting SIRT1 may be of clinical use in beta-catenin-driven malignancies.

Exosomes as a tumor immune escape mechanism: possible therapeutic implications

Directory of Open Access Journals (Sweden)

Hanley Harold H

2008-07-01

Full Text Available Abstract Advances in cancer therapy have been substantial in terms of molecular understanding of disease mechanisms, however these advances have not translated into increased survival in the majority of cancer types. One unsolved problem in current cancer therapeutics is the substantial immune suppression seen in patients. Conventionally, investigations in this area have focused on antigen-nonspecific immune suppressive molecules such as cytokines and T cell apoptosis inducing molecules such as Fas ligand. More recently, studies have demonstrated nanovesicle particles termed exosomes are involved not only in stimulation but also inhibition of immunity in physiological conditions. Interestingly, exosomes secreted by cancer cells have been demonstrated to express tumor antigens, as well as immune suppressive molecules such as PD-1L and FasL. Concentrations of exosomes from plasma of cancer patients have been associated with spontaneous T cell apoptosis, which is associated in some situations with shortened survival. In this paper we place the "exosome-immune suppression" concept in perspective of other tumor immune evasion mechanisms. We conclude by discussing a novel therapeutic approach to cancer immune suppression by extracorporeal removal of exosomes using hollow fiber filtration technology

Short-term Treatment of Daumone Improves Hepatic Inflammation in Aged Mice.

Science.gov (United States)

Park, Jong Hee; Ha, Hunjoo

2015-05-01

Chronic inflammation has been proposed as one of the main molecular mechanisms of aging and age-related diseases. Although evidence in humans is limited, short-term calorie restriction (CR) has been shown to have anti-inflammatory effects in aged experimental animals. We reported on the long-term treatment of daumone, a synthetic pheromone secreted by Caenorhabditis elegans in an energy deficient environment, extends the life-span and attenuates liver injury in aged mice. The present study examined whether late onset short-term treatment of daumone exerts anti-inflammatory effects in the livers of aged mice. Daumone was administered orally at doses of 2 or 20 mg/kg/day for 5 weeks to 24-month-old male C57BL/6J mice. Increased liver macrophage infiltration and gene expression of proinflammatory cytokines in aged mice were significantly attenuated by daumone treatment, suggesting that short-term oral administration of daumone may have hepatoprotective effects. Daumone also dose-dependently suppressed tumor necrosis factor-α (TNF-α)-induced nuclear factor-κB (NF-κB) phosphorylation in HepG2 cells. The present data demonstrated that short-term treatment of daumone has anti-inflammatory effects in aged mouse livers possibly through suppression of NF-κB signaling and suggest that daumone may become a lead compound targeting aging and age-associated diseases.

The Fbw7 tumor suppressor targets KLF5 for ubiquitin-mediated degradation and suppresses breast cell proliferation.

Science.gov (United States)

Zhao, Dong; Zheng, Han-Qiu; Zhou, Zhongmei; Chen, Ceshi

2010-06-01

Fbw7 is a tumor suppressor frequently inactivated in cancers. The KLF5 transcription factor promotes breast cell proliferation and tumorigenesis through upregulating FGF-BP. The KLF5 protein degrades rapidly through the ubiquitin proteasome pathway. Here, we show that the Skp1-CUL1-Fbw7 E3 ubiquitin ligase complex (SCF(Fbw7)) targets KLF5 for ubiquitin-mediated degradation in a GSK3beta-mediated KLF5 phosphorylation-dependent manner. Mutation of the critical S303 residue in the KLF5 Cdc4 phospho-degrons motif ((303)SPPSS) abolishes the protein interaction, ubiquitination, and degradation by Fbw7. Inactivation of endogenous Fbw7 remarkably increases the endogenous KLF5 protein abundances. Endogenous Fbw7 suppresses the FGF-BP gene expression and breast cell proliferation through targeting KLF5 for degradation. These findings suggest that Fbw7 inhibits breast cell proliferation at least partially through targeting KLF5 for proteolysis. This new regulatory mechanism of KLF5 degradation may result in useful diagnostic and therapeutic targets for breast cancer and other cancers. Copyright 2010 AACR.

The Biodistribution and Immune Suppressive Effects of Breast Cancer-Derived Exosomes.

Science.gov (United States)

Wen, Shu Wen; Sceneay, Jaclyn; Lima, Luize Goncalves; Wong, Christina S F; Becker, Melanie; Krumeich, Sophie; Lobb, Richard J; Castillo, Vanessa; Wong, Ke Ni; Ellis, Sarah; Parker, Belinda S; Möller, Andreas

2016-12-01

Small membranous secretions from tumor cells, termed exosomes, contribute significantly to intercellular communication and subsequent reprogramming of the tumor microenvironment. Here, we use optical imaging to determine that exogenously administered fluorescently labeled exosomes derived from highly metastatic murine breast cancer cells distributed predominantly to the lung of syngeneic mice, a frequent site of breast cancer metastasis. At the sites of accumulation, exosomes were taken up by CD45 + bone marrow-derived cells. Subsequent long-term conditioning of naïve mice with exosomes from highly metastatic breast cancer cells revealed the accumulation of myeloid-derived suppressor cells in the lung and liver. This favorable immune suppressive microenvironment was capable of promoting metastatic colonization in the lung and liver, an effect not observed from exosomes derived from nonmetastatic cells and liposome control vesicles. Furthermore, we determined that breast cancer exosomes directly suppressed T-cell proliferation and inhibited NK cell cytotoxicity, and hence likely suppressed the anticancer immune response in premetastatic organs. Together, our findings provide novel insight into the tissue-specific outcomes of breast cancer-derived exosome accumulation and their contribution to immune suppression and promotion of metastases. Cancer Res; 76(23); 6816-27. ©2016 AACR. ©2016 American Association for Cancer Research.

Hepatic Radiofrequency Ablation–induced Stimulation of Distant Tumor Growth Is Suppressed by c-Met Inhibition

Science.gov (United States)

Kumar, Gaurav; Moussa, Marwan; Wang, Yuanguo; Rozenblum, Nir; Galun, Eithan; Goldberg, S. Nahum

2016-01-01

Purpose To elucidate how hepatic radiofrequency (RF) ablation affects distant extrahepatic tumor growth by means of two key molecular pathways. Materials and Methods Rats were used in this institutional animal care and use committee–approved study. First, the effect of hepatic RF ablation on distant subcutaneous in situ R3230 and MATBIII breast tumors was evaluated. Animals were randomly assigned to standardized RF ablation, sham procedure, or no treatment. Tumor growth rate was measured for 3½ to 7 days. Then, tissue was harvested for Ki-67 proliferative indexes and CD34 microvascular density. Second, hepatic RF ablation was performed for hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and c-Met receptor expression measurement in periablational rim, serum, and distant tumor 24 hours to 7 days after ablation. Third, hepatic RF ablation was combined with either a c-Met inhibitor (PHA-665752) or VEGF receptor inhibitor (semaxanib) and compared with sham or drug alone arms to assess distant tumor growth and growth factor levels. Finally, hepatic RF ablation was performed in rats with c-Met–negative R3230 tumors for comparison with the native c-Met–positive line. Tumor size and immunohistochemical quantification at day 0 and at sacrifice were compared with analysis of variance and the two-tailed Student t test. Tumor growth curves before and after treatment were analyzed with linear regression analysis to determine mean slopes of pre- and posttreatment growth curves on a per-tumor basis and were compared with analysis of variance and paired two-tailed t tests. Results After RF ablation of normal liver, distant R3230 tumors were substantially larger at 7 days compared with tumors treated with the sham procedure and untreated tumors, with higher growth rates and tumor cell proliferation. Similar findings were observed in MATBIII tumors. Hepatic RF ablation predominantly increased periablational and serum HGF and downstream distant tumor

IL-33 activates tumor stroma to promote intestinal polyposis.

Science.gov (United States)

Maywald, Rebecca L; Doerner, Stephanie K; Pastorelli, Luca; De Salvo, Carlo; Benton, Susan M; Dawson, Emily P; Lanza, Denise G; Berger, Nathan A; Markowitz, Sanford D; Lenz, Heinz-Josef; Nadeau, Joseph H; Pizarro, Theresa T; Heaney, Jason D

2015-05-12

Tumor epithelial cells develop within a microenvironment consisting of extracellular matrix, growth factors, and cytokines produced by nonepithelial stromal cells. In response to paracrine signals from tumor epithelia, stromal cells modify the microenvironment to promote tumor growth and metastasis. Here, we identify interleukin 33 (IL-33) as a regulator of tumor stromal cell activation and mediator of intestinal polyposis. In human colorectal cancer, IL-33 expression was induced in the tumor epithelium of adenomas and carcinomas, and expression of the IL-33 receptor, IL1RL1 (also referred to as IL1-R4 or ST2), localized predominantly to the stroma of adenoma and both the stroma and epithelium of carcinoma. Genetic and antibody abrogation of responsiveness to IL-33 in the Apc(Min/+) mouse model of intestinal tumorigenesis inhibited proliferation, induced apoptosis, and suppressed angiogenesis in adenomatous polyps, which reduced both tumor number and size. Similar to human adenomas, IL-33 expression localized to tumor epithelial cells and expression of IL1RL1 associated with two stromal cell types, subepithelial myofibroblasts and mast cells, in Apc(Min/+) polyps. In vitro, IL-33 stimulation of human subepithelial myofibroblasts induced the expression of extracellular matrix components and growth factors associated with intestinal tumor progression. IL-33 deficiency reduced mast cell accumulation in Apc(Min/+) polyps and suppressed the expression of mast cell-derived proteases and cytokines known to promote polyposis. Based on these findings, we propose that IL-33 derived from the tumor epithelium promotes polyposis through the coordinated activation of stromal cells and the formation of a protumorigenic microenvironment.

A Multi-targeted Approach to Suppress Tumor-Promoting Inflammation

Science.gov (United States)

Samadi, Abbas K.; Georgakilas, Alexandros G.; Amedei, Amedeo; Amin, Amr; Bishayee, Anupam; Lokeshwar, Bal L.; Grue, Brendan; Panis, Carolina; Boosani, Chandra S.; Poudyal, Deepak; Stafforini, Diana M.; Bhakta, Dipita; Niccolai, Elena; Guha, Gunjan; Rupasinghe, H.P. Vasantha; Fujii, Hiromasa; Honoki, Kanya; Mehta, Kapil; Aquilano, Katia; Lowe, Leroy; Hofseth, Lorne J.; Ricciardiello, Luigi; Ciriolo, Maria Rosa; Singh, Neetu; Whelan, Richard L.; Chaturvedi, Rupesh; Ashraf, S. Salman; Kumara, HMC Shantha; Nowsheen, Somaira; Mohammed, Sulma I.; Helferich, William G.; Yang, Xujuan

2015-01-01

Cancers harbor significant genetic heterogeneity and patterns of relapse following many therapies are due to evolved resistance to treatment. While efforts have been made to combine targeted therapies, significant levels of toxicity have stymied efforts to effectively treat cancer with multi-drug combinations using currently approved therapeutics. We discuss the relationship between tumor-promoting inflammation and cancer as part of a larger effort to develop a broad-spectrum therapeutic approach aimed at a wide range of targets to address this heterogeneity. Specifically, macrophage migration inhibitory factor, cyclooxygenase-2, transcription factor nuclear factor-kappaB, tumor necrosis factor alpha, inducible nitric oxide synthase, protein kinase B, and CXC chemokines are reviewed as important antiinflammatory targets while curcumin, resveratrol, epigallocatechin gallate, genistein, lycopene, and anthocyanins are reviewed as low-cost, low toxicity means by which these targets might all be reached simultaneously. Future translational work will need to assess the resulting synergies of rationally designed antiinflammatory mixtures (employing low-toxicity constituents), and then combine this with similar approaches targeting the most important pathways across the range of cancer hallmark phenotypes. PMID:25951989

EGCG, a major green tea catechin suppresses breast tumor angiogenesis and growth via inhibiting the activation of HIF-1α and NFκB, and VEGF expression.

Science.gov (United States)

Gu, Jian-Wei; Makey, Kristina L; Tucker, Kevan B; Chinchar, Edmund; Mao, Xiaowen; Pei, Ivy; Thomas, Emily Y; Miele, Lucio

2013-05-02

The role of EGCG, a major green tea catechin in breast cancer therapy is poorly understood. The present study tests the hypothesis that EGCG can inhibit the activation of HIF-1α and NFκB, and VEGF expression, thereby suppressing tumor angiogenesis and breast cancer progression. Sixteen eight-wk-old female mice (C57BL/6 J) were inoculated with 10^6 E0771 (mouse breast cancer) cells in the left fourth mammary gland fat pad. Eight mice received EGCG at 50-100 mg/kg/d in drinking water for 4 weeks. 8 control mice received drinking water only. Tumor size was monitored using dial calipers. At the end of the experiment, blood samples, tumors, heart and limb muscles were collected for measuring VEGF expression using ELISA and capillary density (CD) using CD31 immunohistochemistry. EGCG treatment significantly reduced tumor weight over the control (0.37 ± 0.15 vs. 1.16 ± 0.30 g; P < 0.01), tumor CD (109 ± 20 vs. 156 ± 12 capillary #/mm^2; P < 0.01), tumor VEGF expression (45.72 ± 1.4 vs. 59.03 ± 3.8 pg/mg; P < 0.01), respectively. But, it has no effects on the body weight, heart weight, angiogenesis and VEGF expression in the heart and skeletal muscle of mice. EGCG at 50 μg/ml significantly inhibited the activation of HIF-1α and NFκB as well as VEGF expression in cultured E0771 cells, compared to the control, respectively. These findings support the hypothesis that EGCG, a major green tea catechin, directly targets both tumor cells and tumor vasculature, thereby inhibiting tumor growth, proliferation, migration, and angiogenesis of breast cancer, which is mediated by the inhibition of HIF-1α and NFκB activation as well as VEGF expression.

Tumor producing fibroblast growth factor 23 localized by two-staged venous sampling.

NARCIS (Netherlands)

Boekel, G.A.J van; Ruinemans-Koerts, J.; Joosten, F.; Dijkhuizen, P.; Sorge, A.A. van; Boer, H. de

2008-01-01

BACKGROUND: Tumor-induced osteomalacia is a rare paraneoplastic syndrome characterized by hypophosphatemia, renal phosphate wasting, suppressed 1,25-dihydroxyvitamin D production, and osteomalacia. It is caused by a usually benign mesenchymal tumor producing fibroblast growth factor 23 (FGF-23).

NF-κB Directly Regulates Fas Transcription to Modulate Fas-mediated Apoptosis and Tumor Suppression*

Science.gov (United States)

Liu, Feiyan; Bardhan, Kankana; Yang, Dafeng; Thangaraju, Muthusamy; Ganapathy, Vadivel; Waller, Jennifer L.; Liles, Georgia B.; Lee, Jeffrey R.; Liu, Kebin

2012-01-01

Fas is a member of the death receptor family. Stimulation of Fas leads to induction of apoptotic signals, such as caspase 8 activation, as well as “non-apoptotic” cellular responses, notably NF-κB activation. Convincing experimental data have identified NF-κB as a critical promoter of cancer development, creating a solid rationale for the development of antitumor therapy that suppresses NF-κB activity. On the other hand, compelling data have also shown that NF-κB activity enhances tumor cell sensitivity to apoptosis and senescence. Furthermore, although stimulation of Fas activates NF-κB, the function of NF-κB in the Fas-mediated apoptosis pathway remains largely undefined. In this study, we observed that deficiency of either Fas or FasL resulted in significantly increased incidence of 3-methylcholanthrene-induced spontaneous sarcoma development in mice. Furthermore, Fas-deficient mice also exhibited significantly greater incidence of azoxymethane and dextran sodium sulfate-induced colon carcinoma. In addition, human colorectal cancer patients with high Fas protein in their tumor cells had a longer time before recurrence occurred. Engagement of Fas with FasL triggered NF-κB activation. Interestingly, canonical NF-κB was found to directly bind to the FAS promoter. Blocking canonical NF-κB activation diminished Fas expression, whereas blocking alternate NF-κB increased Fas expression in human carcinoma cells. Moreover, although canonical NF-κB protected mouse embryo fibroblast (MEF) cells from TNFα-induced apoptosis, knocking out p65 diminished Fas expression in MEF cells, resulting in inhibition of FasL-induced caspase 8 activation and apoptosis. In contrast, knocking out p52 increased Fas expression in MEF cells. Our observations suggest that canonical NF-κB is a Fas transcription activator and alternate NF-κB is a Fas transcription repressor, and Fas functions as a suppressor of spontaneous sarcoma and colon carcinoma. PMID:22669972

Blockade of A2b Adenosine Receptor Reduces Tumor Growth and Immune Suppression Mediated by Myeloid-Derived Suppressor Cells in a Mouse Model of Melanoma

Directory of Open Access Journals (Sweden)

Raffaella Iannone

2013-12-01

Full Text Available The A2b receptor (A2bR belongs to the adenosine receptor family. Emerging evidence suggest that A2bR is implicated in tumor progression in some murine tumor models, but the therapeutic potential of targeting A2bR in melanoma has not been examined. This study first shows that melanoma-bearing mice treated with Bay 60-6583, a selective A2bR agonist, had increased melanoma growth. This effect was associated with higher levels of immune regulatory mediators interleukin-10 (IL-10 and monocyte chemoattractant protein 1 (MCP-1 and accumulation of tumor-associated CD11b positive Gr1 positive cells (CD11b+Gr1+ myeloid-derived suppressor cells (MDSCs. Depletion of CD11b+Gr1+ cells completely reversed the protumor activity of Bay 60-6583. Conversely, pharmacological blockade of A2bR with PSB1115 reversed immune suppression in the tumor microenvironment, leading to a significant melanoma growth delay. PSB1115 treatment reduced both levels of IL-10 and MCP-1 and CD11b+Gr1+ cell number in melanoma lesions. These effects were associated with higher frequency of tumor-infiltrating CD8 positive (CD8+ T cells and natural killer T (NKT cells and increased levels of T helper 1 (Th1-like cytokines. Adoptive transfer of CD11b+Gr1+ cells abrogated the antitumor activity of PSB1115. These data suggest that the antitumor activity of PSB1115 relies on its ability to lower accumulation of tumor-infiltrating MDSCs and restore an efficient antitumor T cell response. The antitumor effect of PSB1115 was not observed in melanoma-bearing nude mice. Furthermore, PSB1115 enhanced the antitumor efficacy of dacarbazine. These data indicate that A2bR antagonists such as PSB1115 should be investigated as adjuvants in the treatment of melanoma.

What is a pediatric tumor?

Directory of Open Access Journals (Sweden)

Mora J

2012-11-01

Full Text Available Jaume Mora1,21Department of Oncology, 2Developmental Tumor Biology Laboratory, Hospital Sant Joan de Deu, Fundacio Sant Joan de Deu, Barcelona, SpainAbstract: Working together with medical oncologists, the question of whether a Ewing sarcoma in a 25-year-old is a pediatric tumor comes up repeatedly. Like Ewing's, some tumors present characteristically at ages that cross over what has been set as the definition of pediatrics (15 years, 18 years, or 21 years?. Pediatric oncology textbooks, surprisingly, do not address the subject of defining a pediatric tumor. They all begin with an epidemiology chapter defining the types of tumors appearing at distinct stages of childhood, adolescence, and young adulthood. Describing the epidemiology of tumors in relation to age, it becomes clear that the disease is related to the phenomenon of aging. The question, however, remains: is there a biological definition of what pediatric age is? And if so, will tumors occurring during this period of life have anything to do with such biological definition? With the aim of finding an objective definition, the fundamental concepts of what defines "pediatrics" was reviewed and then the major features of tumors arising during development were analyzed. The tumors were explored from the perspective of a host immersed in the normal process of growth and development. This physiological process, from pluripotential and undifferentiated cells, makes possible the differentiation, maturation, organization, and function of tissues, organs, and apparatus. A biological definition of pediatric tumors and the infancy–childhood–puberty classification of developmental tumors according to the infancy–childhood–puberty model of normal human development are proposed.Keywords: growth and development, pediatric tumor, infant, childhood and adolescence, pubertal tumors

The human ARF tumor suppressor senses blastema activity and suppresses epimorphic tissue regeneration

Science.gov (United States)

Hesse, Robert G; Kouklis, Gayle K; Ahituv, Nadav; Pomerantz, Jason H

2015-01-01

The control of proliferation and differentiation by tumor suppressor genes suggests that evolution of divergent tumor suppressor repertoires could influence species’ regenerative capacity. To directly test that premise, we humanized the zebrafish p53 pathway by introducing regulatory and coding sequences of the human tumor suppressor ARF into the zebrafish genome. ARF was dormant during development, in uninjured adult fins, and during wound healing, but was highly expressed in the blastema during epimorphic fin regeneration after amputation. Regenerative, but not developmental signals resulted in binding of zebrafish E2f to the human ARF promoter and activated conserved ARF-dependent Tp53 functions. The context-dependent activation of ARF did not affect growth and development but inhibited regeneration, an unexpected distinct tumor suppressor response to regenerative versus developmental environments. The antagonistic pleiotropic characteristics of ARF as both tumor and regeneration suppressor imply that inducing epimorphic regeneration clinically would require modulation of ARF –p53 axis activation. DOI: http://dx.doi.org/10.7554/eLife.07702.001 PMID:26575287

Let-7b-mediated suppression of basigin expression and metastasis in mouse melanoma cells

International Nuclear Information System (INIS)

Fu, Tzu-Yen; Chang, Chia-Che; Lin, Chun-Ting; Lai, Cong-Hao; Peng, Shao-Yu; Ko, Yi-Ju; Tang, Pin-Chi

2011-01-01

Basigin (Bsg), also called extracellular matrix metalloproteinase inducer (EMMPRIN), is highly expressed on the surface of tumor cells and stimulates adjacent fibroblasts or tumor cells to produce matrix metalloproteinases (mmps). It has been shown that Bsg plays an important role in growth, development, cell differentiation, and tumor progression. MicroRNAs (miRNAs) are a class of short endogenous non-protein coding RNAs of 20-25 nucleotides (nt) that function as post-transcriptional regulators of gene expression by base-pairing to their target mRNAs and thereby mediate cleavage of target mRNAs or translational repression. In this study, let-7b, one of the let-7 family members, was investigated for its effect on the growth and invasiveness of the mouse melanoma cell line B16-F10. We have shown that let-7b can suppress the expression of Bsg in B16-F10 cells and also provided evidence that this suppression could result in the indirect suppression of mmp-9. The ability of B16-F10 cells transfected with let-7b to invade or migrate was significantly reduced. In addition, let-7b transfected B16-F10 cells displayed an inhibition of both cellular proliferation and colony formation. Furthermore, it was shown that the overexpression of let-7b in B16-F10 cells could reduce lung metastasis. Taken together, the present study identifies let-7b as a tumor suppressor that represses cancer cell proliferation and migration as well as tumor metastasis in mouse melanoma cells.

Let-7b-mediated suppression of basigin expression and metastasis in mouse melanoma cells

Energy Technology Data Exchange (ETDEWEB)

Fu, Tzu-Yen [Department of Animal Science, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Chang, Chia-Che [Institute of Biomedical Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Graduate Institute of Basic Medical Science, China Medical University, 91 Hsueh Shih Road, Taichung 40402, Taiwan (China); Lin, Chun-Ting [Department of Animal Science, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Lai, Cong-Hao [Institute of Biomedical Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Department of Life Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Peng, Shao-Yu; Ko, Yi-Ju [Department of Animal Science, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Tang, Pin-Chi, E-mail: pctang@dragon.nchu.edu.tw [Department of Animal Science, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China)

2011-02-15

Basigin (Bsg), also called extracellular matrix metalloproteinase inducer (EMMPRIN), is highly expressed on the surface of tumor cells and stimulates adjacent fibroblasts or tumor cells to produce matrix metalloproteinases (mmps). It has been shown that Bsg plays an important role in growth, development, cell differentiation, and tumor progression. MicroRNAs (miRNAs) are a class of short endogenous non-protein coding RNAs of 20-25 nucleotides (nt) that function as post-transcriptional regulators of gene expression by base-pairing to their target mRNAs and thereby mediate cleavage of target mRNAs or translational repression. In this study, let-7b, one of the let-7 family members, was investigated for its effect on the growth and invasiveness of the mouse melanoma cell line B16-F10. We have shown that let-7b can suppress the expression of Bsg in B16-F10 cells and also provided evidence that this suppression could result in the indirect suppression of mmp-9. The ability of B16-F10 cells transfected with let-7b to invade or migrate was significantly reduced. In addition, let-7b transfected B16-F10 cells displayed an inhibition of both cellular proliferation and colony formation. Furthermore, it was shown that the overexpression of let-7b in B16-F10 cells could reduce lung metastasis. Taken together, the present study identifies let-7b as a tumor suppressor that represses cancer cell proliferation and migration as well as tumor metastasis in mouse melanoma cells.

Risk of new tumors in von Hippel-Lindau patients depends on age and genotype

DEFF Research Database (Denmark)

Binderup, Marie Louise Mølgaard; Budtz-Jørgensen, Esben; Bisgaard, Søs Marie Luise

2016-01-01

PURPOSE: The von Hippel-Lindau (vHL) phenotype is variable, which complicates genetic counseling and surveillance. We describe how the rate of new tumor development varies through the lifetimes of vHL patients and how it is influenced by age and genotype. METHODS: In a national cohort study, we i...... 02 April 2015Genetics in Medicine (2015); doi:10.1038/gim.2015.44....

Forced LIGHT expression in prostate tumors overcomes Treg mediated immunosuppression and synergizes with a prostate tumor therapeutic vaccine by recruiting effector T lymphocytes.

Science.gov (United States)

Yan, Lisa; Da Silva, Diane M; Verma, Bhavna; Gray, Andrew; Brand, Heike E; Skeate, Joseph G; Porras, Tania B; Kanodia, Shreya; Kast, W Martin

2015-02-15

LIGHT, a ligand for lymphotoxin-β receptor (LTβR) and herpes virus entry mediator, is predominantly expressed on activated immune cells and LTβR signaling leads to the recruitment of lymphocytes. The interaction between LIGHT and LTβR has been previously shown to activate immune cells and result in tumor regression in a virally-induced tumor model, but the role of LIGHT in tumor immunosuppression or in a prostate cancer setting, where self antigens exist, has not been explored. We hypothesized that forced expression of LIGHT in prostate tumors would shift the pattern of immune cell infiltration toward an anti-tumoral milieu, would inhibit T regulatory cells (Tregs) and would induce prostate cancer tumor associated antigen (TAA) specific T cells that would eradicate tumors. Real Time PCR was used to evaluate expression of forced LIGHT and other immunoregulatory genes in prostate tumors samples. For in vivo studies, adenovirus encoding murine LIGHT was injected intratumorally into TRAMP-C2 prostate cancer cell tumor bearing mice. Chemokine and cytokine concentrations were determined by multiplex ELISA. Flow cytometry was used to phenotype tumor infiltrating lymphocytes and expression of LIGHT on the tumor cell surface. Tumor-specific lymphocytes were quantified via ELISpot assay. Treg induction and Treg suppression assays determined Treg functionality after LIGHT treatment. LIGHT in combination with a therapeutic vaccine, PSCA TriVax, reduced tumor burden. LIGHT expression peaked within 48 hr of infection, recruited effector T cells that recognized mouse prostate stem cell antigen (PSCA) into the tumor microenvironment, and inhibited infiltration of Tregs. Tregs isolated from tumor draining lymph nodes had impaired suppressive capability after LIGHT treatment. Forced LIGHT treatment combined with PSCA TriVax therapeutic vaccination delays prostate cancer progression in mice by recruiting effector T lymphocytes to the tumor and inhibiting Treg mediated

Explicit hypoxia targeting with tumor suppression by creating an "obligate" anaerobic Salmonella Typhimurium strain.

Science.gov (United States)

Yu, Bin; Yang, Mei; Shi, Lei; Yao, Yandan; Jiang, Qinqin; Li, Xuefei; Tang, Lei-Han; Zheng, Bo-Jian; Yuen, Kwok-Yung; Smith, David K; Song, Erwei; Huang, Jian-Dong

2012-01-01

Using bacteria as therapeutic agents against solid tumors is emerging as an area of great potential in the treatment of cancer. Obligate and facultative anaerobic bacteria have been shown to infiltrate the hypoxic regions of solid tumors, thereby reducing their growth rate or causing regression. However, a major challenge for bacterial therapy of cancer with facultative anaerobes is avoiding damage to normal tissues. Consequently the virulence of bacteria must be adequately attenuated for therapeutic use. By placing an essential gene under a hypoxia conditioned promoter, SalmonellaTyphimurium strain SL7207 was engineered to survive only in anaerobic conditions (strain YB1) without otherwise affecting its functions. In breast tumor bearing nude mice, YB1 grew within the tumor, retarding its growth, while being rapidly eliminated from normal tissues. YB1 provides a safe bacterial vector for anti-tumor therapies without compromising the other functions or tumor fitness of the bacterium as attenuation methods normally do.

Effects of whole-body irradiation on neonatally thymectomized mice. Incidence of benign and malignant tumors

International Nuclear Information System (INIS)

Anderson, R.E.; Howarth, J.L.; Troup, G.M.

1978-01-01

The individual and combined effects of neonatal thymectomy and whole-body irradiation on the prevalence of benign and malignant tumors in germ-free female mice of the Charles Rivers line were studied to determine if a portion of the tumorigenic effects of irradiation can be attributed to injury of the thymic-dependent component of the immune response. Neonatal thymectomy increased (a) the incidence of benign and malignant tumors and (b) the prevalence of multiple primary neoplasms in an individual mouse. Whole-body exposure to 700 rad at 6 weeks of age further increased the incidence of tumors, but the relative magnitude of this increase was less pronounced than in sham-operated controls. Thus, the cumulative effects of thymectomy plus irradiation are less pronounced than the sum of the individual effects. One of several possible explanations for this observation is that a portion of the carcinogenic effects of whole-body irradiation is mediated by suppression of the thymic-dependent component of the immune response

TIE-2 and VEGFR kinase activities drive immunosuppressive function of TIE-2-expressing monocytes in human breast tumors.

Science.gov (United States)

Ibberson, Mark; Bron, Sylvian; Guex, Nicolas; Faes-van't Hull, Eveline; Ifticene-Treboux, Assia; Henry, Luc; Lehr, Hans-Anton; Delaloye, Jean-François; Coukos, George; Xenarios, Ioannis; Doucey, Marie-Agnès

2013-07-01

Tumor-associated TIE-2-expressing monocytes (TEM) are highly proangiogenic cells critical for tumor vascularization. We previously showed that, in human breast cancer, TIE-2 and VEGFR pathways control proangiogenic activity of TEMs. Here, we examine the contribution of these pathways to immunosuppressive activity of TEMs. We investigated the changes in immunosuppressive activity of TEMs and gene expression in response to specific kinase inhibitors of TIE-2 and VEGFR. The ability of tumor TEMs to suppress tumor-specific T-cell response mediated by tumor dendritic cells (DC) was measured in vitro. Characterization of TEM and DC phenotype in addition to their interaction with T cells was done using confocal microscopic images analysis of breast carcinomas. TEMs from breast tumors are able to suppress tumor-specific immune responses. Importantly, proangiogenic and suppressive functions of TEMs are similarly driven by TIE-2 and VEGFR kinase activity. Furthermore, we show that tumor TEMs can function as antigen-presenting cells and elicit a weak proliferation of T cells. Blocking TIE-2 and VEGFR kinase activity induced TEMs to change their phenotype into cells with features of myeloid dendritic cells. We show that immunosuppressive activity of TEMs is associated with high CD86 surface expression and extensive engagement of T regulatory cells in breast tumors. TIE-2 and VEGFR kinase activity was also necessary to maintain high CD86 surface expression levels and to convert T cells into regulatory cells. These results suggest that TEMs are plastic cells that can be reverted from suppressive, proangiogenic cells into cells that are able to mediate an antitumoral immune response. ©2013 AACR.

Genetic and modifying factors that determine the risk of brain tumors

DEFF Research Database (Denmark)

Montelli, Terezinha de Cresci Braga; Peraçoli, Maria Terezinha Serrão; Rogatto, Silvia Regina

2011-01-01

of tumor escape, CNS tumor immunology, immune defects that impair anti-tumor systemic immunity in brain tumor patients and local immuno-suppressive factors within CNS are also reviewed. New hope to treatment perspectives, as dendritic-cell-based vaccines is summarized too. Concluding, it seems well...... responses can alert immune system. However, it is necessary to clarify if individuals with both constitutional defects in immune functions and genetic instability have higher risk of developing brain tumors. Cytogenetic prospective studies and gene copy number variations analysis also must be performed...

Anti-S100A4 antibody suppresses metastasis formation by blocking stroma cell invasion

DEFF Research Database (Denmark)

Klingelhöfer, Jörg; Grum-Schwensen, Birgitte; Beck, Mette K

2012-01-01

microenvironment, making it an attractive target for anti-cancer therapy. In this study, we produced a function-blocking anti-S100A4 monoclonal antibody with metastasis-suppressing activity. Antibody treatment significantly reduced metastatic burden in the lungs of experimental animals by blocking the recruitment...... of T cells to the site of the primary tumor. In vitro studies demonstrated that this antibody efficiently reduced the invasion of T cells in a fibroblast monolayer. Moreover, it was capable of suppressing the invasive growth of human and mouse fibroblasts. We presume therefore that the antibody exerts...... its activity by suppressing stroma cell recruitment to the site of the growing tumor. Our epitope mapping studies suggested that the antibody recognition site overlaps with the target binding interface of human S100A4. We conclude here that this antibody could serve as a solid basis for development...

Tumor necrosis factor alpha is associated with insulin-mediated suppression of free fatty acids and net lipid oxidation in HIV-infected patients with lipodystrophy

DEFF Research Database (Denmark)

Haugaard, SB; Andersen, O; Pedersen, Steen Bønløkke

2006-01-01

Tumor necrosis factor alpha (TNF-alpha) stimulates lipolysis in man. We examined whether plasma TNF-alpha is associated with the degree by which insulin suppresses markers of lipolysis, for example, plasma free fatty acid (FFA) and net lipid oxidation (LIPOX) rate in HIV-infected patients...... with lipodystrophy (LIPO) and those without (controls). LIPOX was estimated by indirect calorimetry during fasting and steady state of a hyperinsulinemic euglycemic clamp in 36 (18 LIPO and 18 controls) normoglycemic HIV-infected men on highly active antiretroviral therapy. In LIPO, TNF-alpha correlated with clamp...... were significant in controls. In all patients, TNF-alpha correlated with clamp FFA (r = 0.61, P

Tumor-secreted miR-214 induces regulatory T cells: a major link between immune evasion and tumor growth

Science.gov (United States)

Yin, Yuan; Cai, Xing; Chen, Xi; Liang, Hongwei; Zhang, Yujing; Li, Jing; Wang, Zuoyun; Chen, Xiulan; Zhang, Wen; Yokoyama, Seiji; Wang, Cheng; Li, Liang; Li, Limin; Hou, Dongxia; Dong, Lei; Xu, Tao; Hiroi, Takachika; Yang, Fuquan; Ji, Hongbin; Zhang, Junfeng; Zen, Ke; Zhang, Chen-Yu

2014-01-01

An increased population of CD4+CD25highFoxp3+ regulatory T cells (Tregs) in the tumor-associated microenvironment plays an important role in cancer immune evasion. However, the underlying mechanism remains unclear. Here we observed an increased secretion of miR-214 in various types of human cancers and mouse tumor models. Tumor-secreted miR-214 was sufficiently delivered into recipient T cells by microvesicles (MVs). In targeted mouse peripheral CD4+ T cells, tumor-derived miR-214 efficiently downregulated phosphatase and tensin homolog (PTEN) and promoted Treg expansion. The miR-214-induced Tregs secreted higher levels of IL-10 and promoted tumor growth in nude mice. Furthermore, in vivo studies indicated that Treg expansion mediated by cancer cell-secreted miR-214 resulted in enhanced immune suppression and tumor implantation/growth in mice. The MV delivery of anti-miR-214 antisense oligonucleotides (ASOs) into mice implanted with tumors blocked Treg expansion and tumor growth. Our study reveals a novel mechanism through which cancer cell actively manipulates immune response via promoting Treg expansion. PMID:25223704

Prevention of Human Lymphoproliferative Tumor Formation in Ovarian Cancer Patient-Derived Xenografts

Directory of Open Access Journals (Sweden)

Kristina A. Butler

2017-08-01

Full Text Available Interest in preclinical drug development for ovarian cancer has stimulated development of patient-derived xenograft (PDX or tumorgraft models. However, the unintended formation of human lymphoma in severe combined immunodeficiency (SCID mice from Epstein-Barr virus (EBV–infected human lymphocytes can be problematic. In this study, we have characterized ovarian cancer PDXs which developed human lymphomas and explore methods to suppress lymphoproliferative growth. Fresh human ovarian tumors from 568 patients were transplanted intraperitoneally in SCID mice. A subset of PDX models demonstrated atypical patterns of dissemination with mediastinal masses, hepatosplenomegaly, and CD45-positive lymphoblastic atypia without ovarian tumor engraftment. Expression of human CD20 but not CD3 supported a B-cell lineage, and EBV genomes were detected in all lymphoproliferative tumors. Immunophenotyping confirmed monoclonal gene rearrangements consistent with B-cell lymphoma, and global gene expression patterns correlated well with other human lymphomas. The ability of rituximab, an anti-CD20 antibody, to suppress human lymphoproliferation from a patient's ovarian tumor in SCID mice and prevent growth of an established lymphoma led to a practice change with a goal to reduce the incidence of lymphomas. A single dose of rituximab during the primary tumor heterotransplantation process reduced the incidence of CD45-positive cells in subsequent PDX lines from 86.3% (n = 117 without rituximab to 5.6% (n = 160 with rituximab, and the lymphoma rate declined from 11.1% to 1.88%. Taken together, investigators utilizing PDX models for research should routinely monitor for lymphoproliferative tumors and consider implementing methods to suppress their growth.

Problems of radiotherapy on the brain tumors in children less than two years of age

Energy Technology Data Exchange (ETDEWEB)

Miyagami, Mitsusuke; Tsubokawa, Takashi (Nihon Univ., Tokyo (Japan). School of Medicine); Nishimoto, Hiroshi; Ueno, Yuhichi

1990-06-01

Impaired growth and mental or developmental disturbance due to radiotherapy for 10 cases of brain tumors in the children ages less than 2 years old were evaluated. Six cases of brain tumor which did not involve the hypothalamic-pituitary axis, were followed more than 2 years after cranial or craniospinal irradiation. Four cases irradiated greater than 2900 rad to the whole brain all revealed markedly lower body heights than -2 SD of the medium. Growth impairment was found to be progressive over time, and markedly evident after 2 years following cranial or craniospinal radiotherapy. Somatomedin C in the blood was measured in 8 cases of brain tumors in childhood receiving radiotherapy. The measurement of Somatomedin C showed markedly low values measuring 0.19 to 0.54 U/ml (medium; 0.36 U/ml) in children having lower body height than -2 SD. Mental retardation or developmental disturbances were found in IQ or DQ tests in all of 5 infants or children younger than 2 years with brain tumors who got radiotherapy over 2900 rad to the whole brain. A case of craniopharyngioma, which had 5400 rad for tumor localization at the hypothalamus-pituitary axis and showed markedly low height, was given growth hormone and grew to normal height without distinct side effects. It was suggested that radiotherapy for brain tumors in infants or children should have special care in deciding the dose, field and time of radiation. If low height due to radiotherapy results, growth hormone therapy should be used for its treatment in childhood. (author).

State of cellular and humoral immune system in women of reproductive age with tumor-like ovary formations

Directory of Open Access Journals (Sweden)

O. S. Shapoval

2014-12-01

Full Text Available Aim. Violations occurring in the immune system in women with ovary tumor-like formations are one of the most important factors in the pathogenesis and development of the disease. In order to study features of immune disorders in 105 women of reproductive age with tumor-like ovary formations determination of cellular and humoral immunity indices was carried out. Methods and results. Variants of immunological reactivity in women with tumor-like ovary formations with different possibilities of reproductive function implementing were established. Conclusion. This indicates that the identification of one of the variants of immunological reactivity disorder in the precurative stage is one of the components of the effective prescribed therapy necessary to select the appropriate tactics of medical correction of homeostasis.

Withaferin A Suppresses Liver Tumor Growth in a Nude Mouse ...

African Journals Online (AJOL)

tumor cell invasiveness in colon cancer [7] and is related to angiogenesis in ... Hsp90, phosphorylated STAT3 and annexin II. [18,20-24]. ..... Herbstritt CJ, Ruiz A, Zhang L, Hanson AD, Conner. BP, Rougas J, Pribluda VS. Withaferin A is a ...

Pharmacological blockade of cholesterol trafficking by cepharanthine in endothelial cells suppresses angiogenesis and tumor growth.

Science.gov (United States)

Lyu, Junfang; Yang, Eun Ju; Head, Sarah A; Ai, Nana; Zhang, Baoyuan; Wu, Changjie; Li, Ruo-Jing; Liu, Yifan; Yang, Chen; Dang, Yongjun; Kwon, Ho Jeong; Ge, Wei; Liu, Jun O; Shim, Joong Sup

2017-11-28

Cholesterol is an important modulator of membrane protein function and signaling in endothelial cells, thus making it an emerging target for anti-angiogenic agents. In this study, we employed a phenotypic screen that detects intracellular cholesterol distribution in endothelial cells (HUVEC) and identified 13 existing drugs as cholesterol trafficking inhibitors. Cepharanthine, an approved drug for anti-inflammatory and cancer management use, was amongst the candidates, which was selected for in-depth mechanistic studies to link cholesterol trafficking and angiogenesis. Cepharanthine inhibited the endolysosomal trafficking of free-cholesterol and low-density lipoprotein in HUVEC by binding to Niemann-Pick disease, type C1 (NPC1) protein and increasing the lysosomal pH. The blockade of cholesterol trafficking led to a cholesterol-dependent dissociation of mTOR from the lysosomes and inhibition of its downstream signaling. Cepharanthine inhibited angiogenesis in HUVEC and in zebrafish in a cholesterol-dependent manner. Furthermore, cepharanthine suppressed tumor growth in vivo by inhibiting angiogenesis and it enhanced the antitumor activity of the standard chemotherapy cisplatin in lung and breast cancer xenografts in mice. Altogether, these results strongly support the idea that cholesterol trafficking is a viable drug target for anti-angiogenesis and that the inhibitors identified among existing drugs, such as cepharanthine, could be potential anti-angiogenic and antitumor agents. Copyright © 2017 Elsevier B.V. All rights reserved.

Inflammatory cytokine tumor necrosis factor α suppresses neuroprotective endogenous erythropoietin from astrocytes mediated by hypoxia-inducible factor-2α.

Science.gov (United States)

Nagaya, Yoshiaki; Aoyama, Mineyoshi; Tamura, Tetsuya; Kakita, Hiroki; Kato, Shin; Hida, Hideki; Saitoh, Shinji; Asai, Kiyofumi

2014-12-01

Interest in erythropoietin (EPO) as a neuroprotective mediator has grown since it was found that systemically administered EPO is protective in several animal models of disease. However, given that the blood-brain barrier limits EPO entry into the brain, alternative approaches that induce endogenous EPO production in the brain may be more effective clinically and associated with fewer untoward side-effects. Astrocytes are the main source of EPO in the central nervous system. In the present study we investigated the effect of the inflammatory cytokine tumor necrosis factor α (TNFα) on hypoxia-induced upregulation of EPO in rat brain. Hypoxia significantly increased EPO mRNA expression in the brain and kidney, and this increase was suppressed by TNFα in vivo. In cultured astrocytes exposed to hypoxic conditions for 6 and 12 h, TNFα suppressed the hypoxia-induced increase in EPO mRNA expression in a concentration-dependent manner. TNFα inhibition of hypoxia-induced EPO expression was mediated primarily by hypoxia-inducible factor (HIF)-2α rather than HIF-1α. The effects of TNFα in reducing hypoxia-induced upregulation of EPO mRNA expression probably involve destabilization of HIF-2α, which is regulated by the nuclear factor (NF)-κB signaling pathway. TNFα treatment attenuated the protective effects of astrocytes on neurons under hypoxic conditions via EPO signaling. The effective blockade of TNFα signaling may contribute to the maintenance of the neuroprotective effects of EPO even under hypoxic conditions with an inflammatory response. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

A reason for intermittent fasting to suppress the awakening of dormant breast tumors.

NARCIS (Netherlands)

Lankelma, J.; Kooi, B.W.; Krab, K.; Dorsman, J.C.; Joenje, H.; Westerhoff, H.V.

2015-01-01

For their growth, dormant tumors, which lack angiogenesis may critically depend on gradients of nutrients and oxygen from the nearest blood vessel. Because for oxygen depletion the distance from the nearest blood vessel to depletion will generally be shorter than for glucose depletion, such tumors

A reason for intermittent fasting to suppress the awakening of dormant breast tumors

NARCIS (Netherlands)

Lankelma, J.; Kooi, B.; Krab, K.; Dorsman, J.C.; Joenje, H.; Westerhoff, H.V.

2015-01-01

For their growth, dormant tumors, which lack angiogenesis may critically depend on gradients of nutrients and oxygen from the nearest blood vessel. Because for oxygen depletion the distance from the nearest blood vessel to depletion will generally be shorter than for glucose depletion, such tumors

Memory suppression is an active process that improves over childhood

Directory of Open Access Journals (Sweden)

Pedro M Paz-Alonso

2009-09-01

Full Text Available We all have memories that we prefer not to think about. The ability to suppress retrieval of unwanted memories has been documented in behavioral and neuroimaging research using the Think/No-Think (TNT paradigm with adults. Attempts to stop memory retrieval are associated with increased activation of lateral prefrontal cortex (PFC and concomitant reduced activation in medial temporal lobe (MTL structures. However, the extent to which children have the ability to actively suppress their memories is unknown. This study investigated memory suppression in middle childhood using the TNT paradigm. Forty children aged 8 to 12 and 30 young adults were instructed either to remember (Think or suppress (No-Think the memory of the second word of previously studied word-pairs, when presented with the first member as a reminder. They then performed two different cued recall tasks, testing their memory for the second word in each pair after the Think/No-Think phase using the same first studied word within the pair as a cue (intra-list cue and also an independent cue (extra-list cue. Children exhibited age-related improvements in memory suppression from age 8 to 12 in both memory tests, against a backdrop of overall improvements in declarative memory over this age range. These findings suggest that memory suppression is an active process that develops during late childhood, likely due to an age-related refinement in the ability to engage PFC to down-regulate activity in areas involved in episodic retrieval.

Paracrine interactions of cancer-associated fibroblasts, macrophages and endothelial cells: tumor allies and foes.

Science.gov (United States)

Ronca, Roberto; Van Ginderachter, Jo A; Turtoi, Andrei

2018-01-01

Tumor stroma is composed of many cellular subtypes, of which the most abundant are fibroblasts, macrophages and endothelial cells. During the process of tissue injury, these three cellular subtypes must coordinate their activity to efficiently contribute to tissue regeneration. In tumor, this mechanism is hijacked by cancer cells, which rewire the interaction of stromal cells to benefit tumor development. The present review aims at summarizing most relevant information concerning both pro-tumorigenic and anti-tumorigenic actions implicating the three stromal cell subtypes as well as their mutual interactions. Although stromal cells are generally regarded as tumor-supportive and at will manipulated by cancer cells, several novel studies point at many defaults in cancer cell-mediated stromal reprograming. Indeed, parts of initial tissue-protective and homeostatic functions of the stromal cells remain in place even after tumor development. Both tumor-supportive and tumor-suppressive functions have been well described for macrophages, whereas similar results are emerging for fibroblasts and endothelial cells. Recent success of immunotherapies have finally brought the long awaited proof that stroma is key for efficient tumor targeting. However, a better understanding of paracrine stromal interactions is needed in order to encourage drug development not only aiming at disruption of tumor-supportive communication but also re-enforcing, existing, tumor-suppressive mechanisms.

miR-644a Inhibits Cellular Proliferation and Invasion via Suppression of CtBP1 in Gastric Cancer Cells.

Science.gov (United States)

Li, Yingchao; Yan, Xiaoni; Ren, Li; Li, Yang

2018-01-19

Epithelial-mesenchymal transition (EMT) is one of the most important mechanisms in the metastasis of various cancers, including gastric cancer (GC). In this study, we explored the putative significance of miR-644a and its role in EMT-mediated metastasis of GC. We first detected the expression of miR-644a in a cohort of 107 GC tissues using quantitative RT-PCR. The expression of miR-644a was suppressed in GC tissues and was associated with a later clinical stage and tumor metastasis. Restoring the expression of miR-644a could significantly suppress the migration and invasion of HGC-27 and SGC-7901 cells, which might be correlated to its suppressive effect on the EMT process. We also found that carboxyl-terminal-binding protein 1 (CtBP1) was a putative target gene of miR-644a in GC and might be involved in the suppressive effect. Collectively, through targeting CtBP1-mediated suppression of the EMT process, miR-644a might suppress the tumor metastasis of GC cells.

MAZ-binding G4-decoy with locked nucleic acid and twisted intercalating nucleic acid modifications suppresses KRAS in pancreatic cancer cells and delays tumor growth in mice

DEFF Research Database (Denmark)

Cogoi, Susanna; Zorzet, Sonia; Rapozzi, Valentina

2013-01-01

and stability, two polycyclic aromatic hydrocarbon units (TINA or AMANY) were inserted internally, to cap the quadruplex. The most active G4-decoy (2998), which had two para-TINAs, strongly suppressed KRAS expression in Panc-1 cells. It also repressed their metabolic activity (IC50 = 520 nM), and it inhibited...... cell growth and colony formation by activating apoptosis. We finally injected 2998 and control oligonucleotides 5153, 5154 (2 nmol/mouse) intratumorally in SCID mice bearing a Panc-1 xenograft. After three treatments, 2998 reduced tumor xenograft growth by 64% compared with control and increased...

Poppers: large cancer increase and immune suppression in animal tests.

Science.gov (United States)

James, J S

1999-04-16

A study on mice injected with cancer cells and then exposed to isobutyl nitrite (poppers) revealed that inhalant-treated mice developed tumors more readily and rapidly than control mice. The control mice were also injected with cancer cells, but only breathed air. Related studies found that poppers suppress certain immune functions involved in killing tumor cells. These studies suggest that further research of persons with HIV/AIDS who use poppers is needed to determine if they are at a high risk for developing malignancies.

Reducing confounding and suppression effects in TCGA data: an integrated analysis of chemotherapy response in ovarian cancer

Directory of Open Access Journals (Sweden)

Hsu Fang-Han

2012-10-01

Full Text Available Abstract Background Despite initial response in adjuvant chemotherapy, ovarian cancer patients treated with the combination of paclitaxel and carboplatin frequently suffer from recurrence after few cycles of treatment, and the underlying mechanisms causing the chemoresistance remain unclear. Recently, The Cancer Genome Atlas (TCGA research network concluded an ovarian cancer study and released the dataset to the public. The TCGA dataset possesses large sample size, comprehensive molecular profiles, and clinical outcome information; however, because of the unknown molecular subtypes in ovarian cancer and the great diversity of adjuvant treatments TCGA patients went through, studying chemotherapeutic response using the TCGA data is difficult. Additionally, factors such as sample batches, patient ages, and tumor stages further confound or suppress the identification of relevant genes, and thus the biological functions and disease mechanisms. Results To address these issues, herein we propose an analysis procedure designed to reduce suppression effect by focusing on a specific chemotherapeutic treatment, and to remove confounding effects such as batch effect, patient's age, and tumor stages. The proposed procedure starts with a batch effect adjustment, followed by a rigorous sample selection process. Then, the gene expression, copy number, and methylation profiles from the TCGA ovarian cancer dataset are analyzed using a semi-supervised clustering method combined with a novel scoring function. As a result, two molecular classifications, one with poor copy number profiles and one with poor methylation profiles, enriched with unfavorable scores are identified. Compared with the samples enriched with favorable scores, these two classifications exhibit poor progression-free survival (PFS and might be associated with poor chemotherapy response specifically to the combination of paclitaxel and carboplatin. Significant genes and biological processes are

Bone loss in long-term suppressive therapy with thyroid hormone

International Nuclear Information System (INIS)

Firooznia, H.; Blum, M.; Golimbu, C.; Rafii, M.

1987-01-01

The trabecular bone density of the spine was measured with CT in 31 women, aged 39-79 years, who had received an average of 13.5 years of thyroid suppressive therapy. The spinal trabecular bone density values in 24 (77%), 18 (58%), and 13 subjects (42%) were respectively below the mean for healthy age-matched controls, the fifth percentile for healthy premenopausal women, and the fifth percentile for age-matched controls. Cortical and trabecular bone loss occurs in hyperthyroidism. Although the intent is not to cause hyperthyroidism in subjects on suppressive therapy, supraphysical doses of thyroid hormone are usually necessary for suppression of thyroid-stimulating hormone. In this study, bone loss was noted in these subjects. Because most of these patients are middle-aged or postmenopausal women, who are at risk for osteoporosis, it is important to be aware of the risk of additional bone loss induced by thyroid suppressive therapy in them

Contribution to Tumor Angiogenesis From Innate Immune Cells Within the Tumor Microenvironment: Implications for Immunotherapy

Directory of Open Access Journals (Sweden)

Adriana Albini

2018-04-01

Full Text Available The critical role of angiogenesis in promoting tumor growth and metastasis is strongly established. However, tumors show considerable variation in angiogenic characteristics and in their sensitivity to antiangiogenic therapy. Tumor angiogenesis involves not only cancer cells but also various tumor-associated leukocytes (TALs and stromal cells. TALs produce chemokines, cytokines, proteases, structural proteins, and microvescicles. Vascular endothelial growth factor (VEGF and inflammatory chemokines are not only major proangiogenic factors but are also immune modulators, which increase angiogenesis and lead to immune suppression. In our review, we discuss the regulation of angiogenesis by innate immune cells in the tumor microenvironment, specific features, and roles of major players: macrophages, neutrophils, myeloid-derived suppressor and dendritic cells, mast cells, γδT cells, innate lymphoid cells, and natural killer cells. Anti-VEGF or anti-inflammatory drugs could balance an immunosuppressive microenvironment to an immune permissive one. Anti-VEGF as well as anti-inflammatory drugs could therefore represent partners for combinations with immune checkpoint inhibitors, enhancing the effects of immune therapy.

Exogenous regucalcin suppresses the growth of human liver cancer HepG2 cells in vitro.

Science.gov (United States)

Yamaguchi, Masayoshi; Murata, Tomiyasu

2018-04-05

Regucalcin, which its gene is localized on the X chromosome, plays a pivotal role as a suppressor protein in signal transduction in various types of cells and tissues. Regucalcin gene expression has been demonstrated to be suppressed in various tumor tissues of animal and human subjects, suggesting a potential role of regucalcin in carcinogenesis. Regucalcin, which is produced from the tissues including liver, is found to be present in the serum of human subjects and animals. This study was undertaken to determine the effects of exogenous regucalcin on the proliferation in cloned human hepatoma HepG2 cells in vitro. Proliferation of HepG2 cells was suppressed after culture with addition of regucalcin (0.01 – 10 nM) into culture medium. Exogenous regucalcin did not reveal apoptotic cell death in HepG2 cells in vitro. Suppressive effects of regucalcin on cell proliferation were not enhanced in the presence of various signaling inhibitors including tumor necrosis factor-α (TNF-α), Bay K 8644, PD98059, staurosporine, worthomannin, 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole (DRB) or gemcitabine, which were found to suppress the proliferation. In addition, exogenous regucalcin suppressed the formation of colonies of cultured hepatoma cells in vitro. These findings demonstrated that exogenous regucalcin exhibits a suppressive effect on the growth of human hepatoma HepG2 cells, proposing a strategy with the gene therapy for cancer treatment.

Paradox between angiogenesis and oxygen effect in the treatment of tumor

International Nuclear Information System (INIS)

Hayashi, Masanobu

2008-01-01

The paradox in the title is described on recent findings concerning the effects of anti-angiogenetic drugs on possible radiation resistance and sensitivity of tumor tissue. Suppression of angiogenesis leads to inhibition of tumor growth, based on which anti-tumor drugs like anti- vascular endotherial growth factor (VEGF) antibody bevacizumab to suppress the genesis have been developed and clinically used, but they conceivably increase the population of hypoxic tumor cells. Those drugs are essentially used in combination with other chemotherapeutic agents and/or radiation. Hypoxic tumor cells present in the tissue are generally radioresistant. There are reported findings, however, that the drugs sometimes elevate the efficacy of radiotherapy, which hypothesizes that the drugs induces a proangiogenetic state, where increased level of growth factors in the tissue is reduced to normalize the vasculature and thereby reoxygenation occurs, the oxygen effect. Because copper is a cofactor of growth factors like VEGF and basic fibroblast growth factor (bFGF) and essential for angiogenesis, authors have studied the effect of a Cu-chelator, trientine, on transplanted mouse tumors which has been shown to induce apoptosis of the target cells. Combination of the chelator with X-ray irradiation is found effective in tumor growth inhibition and in survival increase. For more effective combination therapy, the interaction occurring in combinations of regimen should be elucidated. (R.T.)

Regional Extent of Peripheral Suppression in Amblyopia.

Science.gov (United States)

Babu, Raiju J; Clavagnier, Simon; Bobier, William R; Thompson, Benjamin; Hess, Robert F

2017-04-01

Previously, we have mapped amblyopic eye suppression within the central 20° of the visual field and observed a gradient of suppression that is strongest in central vision and weakens with increasing eccentricity. In this study, using a large dichoptic display, we extend our novel suppression mapping approach further into the periphery (from 20°-60°) to assess whether suppression continues to decline with eccentricity or plateaus. Sixteen participants with amblyopia (10 with strabismus, 6 with anisometropia without strabismus; mean age: 37.9 ± 11 years) and six normal observers (mean age: 28.3 ± 5 years) took part. The visual stimulus (60° diameter), viewed from 57 cm, was composed of four concentric annuli (5° radius) with alternate contrast polarities starting from an eccentricity of 10°. Each annulus was divided into eight sectors subtending 45° of visual angle. Participants adjusted the contrast of a single sector presented to the fellow eye to match the perceived contrast of the remaining stimulus elements that were presented to the amblyopic eye. A matching contrast that was lower in the fellow eye than the amblyopic eye indicated suppression. Patients with strabismus exhibited significantly stronger interocular suppression than controls across all eccentricities (P = 0.01). Patients with anisometropia did not differ from controls (P = 0.58). Suppression varied significantly with eccentricity (P = 0.005) but this effect did not differ between patient groups (P = 0.217). In amblyopia, suppression is present beyond the central 10° in patients with strabismus. Suppression becomes weaker at greater eccentricities and this may enable peripheral fusion that could be used by binocular treatment methods.

Usefulness of fat suppression MR imagings for head and neck cancers

International Nuclear Information System (INIS)

Kitagawa, Yoshimasa; Ishii, Yasuo; Morihiro, Hironori; Ogasawara, Toshiyuki

1996-01-01

Large amounts of fat and complex anatomy make the head and neck region one of the more challenging areas for MR imagings. The high signal intensity of fat on T1 weighted images (T1W1) has limited the utility of Gd-DTPA in imaging of head and neck lesions. The contrast enhanced lesions may have T1W1 signal intensity similar to fat, which results in diagnostic difficulty. A fat suppression technique used in conjunction with Gd-DTPA ensures that enhancing lesions will not be obscured by high signal from the surrounding fat or by chemical shift artifact. We evaluated the role or chemical shift imagings for fat suppression in the depiction of 15 patients with head and neck cancers. Gd-DTPA-enhanced fat suppression T1W1 were compared with conventional pre and postcontrast T1- and T2W1 using a four-point grading system (Grade 0-3) in detecting and defining the extent of primary lesions and lymphnodes. Gd-DTPA-enhanced fat suppression T1W1 (average score 2.93) which had a score of 3 in 14 patients, were superior to conventional T1W1 (0.73), postcontrast T1W1 (1.80) and T2W1 (1.67). Gd-DTPA enhanced fat suppression T1W1 were particularly beneficial in the detection of central necrosis or extracapsular invasion of neck lymphnodes as well as in defining the extent of tumor invasion to fat-containing areas such as bone marrow or cheek. Our data suggested that fat suppression technique was extremely useful to delineate the primary tumors and regional lymphnodes without increasing scan time or image postprocessing. (author)

Cystatin C deficiency suppresses tumor growth in a breast cancer model through decreased proliferation of tumor cells.

Science.gov (United States)

Završnik, Janja; Butinar, Miha; Prebanda, Mojca Trstenjak; Krajnc, Aleksander; Vidmar, Robert; Fonović, Marko; Grubb, Anders; Turk, Vito; Turk, Boris; Vasiljeva, Olga

2017-09-26

Cysteine cathepsins are proteases that, in addition to their important physiological functions, have been associated with multiple pathologies, including cancer. Cystatin C (CstC) is a major endogenous inhibitor that regulates the extracellular activity of cysteine cathepsins. We investigated the role of cystatin C in mammary cancer using CstC knockout mice and a mouse model of breast cancer induced by expression of the polyoma middle T oncoprotein (PyMT) in the mammary epithelium. We showed that the ablation of CstC reduced the rate of mammary tumor growth. Notably, a decrease in the proliferation of CstC knockout PyMT tumor cells was demonstrated ex vivo and in vitro , indicating a role for this protease inhibitor in signaling pathways that control cell proliferation. An increase in phosphorylated p-38 was observed in CstC knockout tumors, suggesting a novel function for cystatin C in cancer development, independent of the TGF-β pathway. Moreover, proteomic analysis of the CstC wild-type and knockout PyMT primary cell secretomes revealed a decrease in the levels of 14-3-3 proteins in the secretome of knock-out cells, suggesting a novel link between cysteine cathepsins, cystatin C and 14-3-3 proteins in tumorigenesis, calling for further investigations.

T Cell-Tumor Interaction Directs the Development of Immunotherapies in Head and Neck Cancer

Directory of Open Access Journals (Sweden)

A. E. Albers

2010-01-01

Full Text Available The competent immune system controls disease effectively due to induction, function, and regulation of effector lymphocytes. Immunosurveillance is exerted mostly by cytotoxic T-lymphocytes (CTLs while specific immune suppression is associated with tumor malignancy and progression. In squamous cell carcinoma of the head and neck, the presence, activity, but also suppression of tumor-specific CTL have been demonstrated. Functional CTL may exert a selection pressure on the tumor cells that consecutively escape by a combination of molecular and cellular evasion mechanisms. Certain of these mechanisms target antitumor effector cells directly or indirectly by affecting cells that regulate CTL function. This results in the dysfunction or apoptosis of lymphocytes and dysregulated lymphocyte homeostasis. Another important tumor-escape mechanism is to avoid recognition by dysregulation of antigen processing and presentation. Thus, both induction of functional CTL and susceptibility of the tumor and its microenvironment to become T cell targets should be considered in CTL-based immunotherapy.

Usefulness of fat-suppressed Gd-enhanced MR imaging of tongue cancer

International Nuclear Information System (INIS)

Murakami, Shumei; Fuchihata, Hajime; Yoon, Sukja; Furukawa, Souhei; Kawai, Tadahiko; Kishino, Mitsunobu

1999-01-01

To evaluate the usefulness of the fat suppression technique for magnetic resonance imaging of oral tongue cancer. One hundred and fourteen patients underwent both magnetic resonance imaging (MRI) and computed tomography (CT). All patients were clinically diagnosed as having oral tongue cancer shown to be squamous cell carcinoma histopathologically. We used two types of CT and six types of MRI scanning: plain CT, contrast enhanced CT, conventional T1w, conventional PDw, conventional T2w, fat-suppressed (FATS) T1w, Gd-enhanced conventional T1w, and Gd-enhanced FATS T1w images. The focus of our study was Gd-enhanced FATS T1w imaging. Tumor detection rates were as follows: Gd-enhanced FATS T1w MRI, 86.8%; conventional T2w MRI, 71.9%; conventional PDw MRI, 65.8%; Gd-enhanced conventional T1w MRI, 47.4%; contrast enhanced CT, 36.8%; T1w MRI, 20.2%; CT, 10.5%. There were 59 cases in which tumors were detected by Gd-enhanced FATS T1w MRI but not detected by contrast enhanced CT. Gd-enhanced FATS T1w MRI was the best for the tumor detection and Gd-enhanced conventional T1w MRI was not useful in the diagnosis of the tongue cancer. CT imaging must not be the first choice for tumor detection in tongue cancer patients. (author)

Patients with old age or proximal tumors benefit from metabolic syndrome in early stage gastric cancer.

Directory of Open Access Journals (Sweden)

Xiao-li Wei

Full Text Available BACKGROUND: Metabolic syndrome and/or its components have been demonstrated to be risk factors for several cancers. They are also found to influence survival in breast, colon and prostate cancer, but the prognostic value of metabolic syndrome in gastric cancer has not been investigated. METHODS: Clinical data and pre-treatment information of metabolic syndrome of 587 patients diagnosed with early stage gastric cancer were retrospectively collected. The associations of metabolic syndrome and/or its components with clinical characteristics and overall survival in early stage gastric cancer were analyzed. RESULTS: Metabolic syndrome was identified to be associated with a higher tumor cell differentiation (P=0.036. Metabolic syndrome was also demonstrated to be a significant and independent predictor for better survival in patients aged >50 years old (P=0.009 in multivariate analysis or patients with proximal gastric cancer (P=0.047 in multivariate analysis. No association was found between single metabolic syndrome component and overall survival in early stage gastric cancer. In addition, patients with hypertension might have a trend of better survival through a good control of blood pressure (P=0.052 in univariate analysis. CONCLUSIONS: Metabolic syndrome was associated with a better tumor cell differentiation in patients with early stage gastric cancer. Moreover, metabolic syndrome was a significant and independent predictor for better survival in patients with old age or proximal tumors.

Resveratrol (trans-3,5,4'-trihydroxystilbene) suppresses EL4 tumor growth by induction of apoptosis involving reciprocal regulation of SIRT1 and NF-κB.

Science.gov (United States)

Singh, Narendra P; Singh, Udai P; Hegde, Venkatesh L; Guan, Hongbing; Hofseth, Lorne; Nagarkatti, Mitzi; Nagarkatti, Prakash S

2011-08-01

Understanding the molecular mechanisms through which natural products and dietary supplements exhibit anticancer properties is crucial and can lead to drug discovery and chemoprevention. The current study sheds new light on the mode of action of resveratrol (RES), a plant-derived polyphenolic compound, against EL-4 lymphoma growth. Immuno-compromised NOD/SCID mice injected with EL-4 tumor cells and treated with RES (100 mg/kg body weight) showed delayed development and progression of tumor growth and increased mean survival time. RES caused apoptosis in EL4 cells through activation of aryl hydrocarbon receptor (AhR) and upregulation of Fas and FasL expression in vitro. Blocking of RES-induced apoptosis in EL4 cells by FasL mAb, cleavage of caspases and PARP, and release of cytochorme c, demonstrated the participation of both extrinsic and intrinsic pathways of apoptosis. RES also induced upregulation of silent mating type information regulation 2 homolog, 1 (SIRT1) and downregulation of nuclear factor kappa B (NF-κB) in EL4 cells. siRNA-mediated downregulation of SIRT1 in EL4 cells increased the activation of NF-κB but decreased RES-mediated apoptosis, indicating the critical role of SIRT1 in apoptosis via blocking activation of NF-κB. These data suggest that RES-induced SIRT1 upregulation promotes tumor cell apoptosis through negative regulation of NF-κB, leading to suppression of tumor growth. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pediatric liver tumors - a pictorial review

International Nuclear Information System (INIS)

Jha, Priyanka; Tavri, Sidhartha; Patel, Chirag; Gooding, Charles; Daldrup-Link, Heike; Chawla, Soni C.

2009-01-01

Hepatic masses constitute about 5-6% of all intra-abdominal masses in children. The majority of liver tumors in children are malignant; these malignant liver tumors constitute the third most common intra-abdominal malignancy in the pediatric age group after Wilms' tumor and neuroblastoma. Only about one third of the liver tumors are benign. A differential diagnosis of liver tumors in children can be obtained based on the age of the child, clinical information (in particular AFP) and imaging characteristics. The purpose of this review is to report typical clinical and imaging characteristics of benign and malignant primary liver tumors in children. (orig.)

Intravenous miR-144 inhibits tumor growth in diethylnitrosamine-induced hepatocellular carcinoma in mice.

Science.gov (United States)

He, Quan; Wang, Fangfei; Honda, Takashi; Lindquist, Diana M; Dillman, Jonathan R; Timchenko, Nikolai A; Redington, Andrew N

2017-10-01

Previous in vitro studies have demonstrated that miR-144 inhibits hepatocellular carcinoma cell proliferation, invasion, and migration. We have shown that miR-144, injected intravenously, is taken up by the liver and induces endogenous hepatic synthesis of miR-144. We hypothesized that administered miR-144 has tumor-suppressive effects on liver tumor development in vivo. The effects of miR-144 on tumorigenesis and tumor growth were tested in a diethylnitrosamine-induced hepatocellular carcinoma mouse model. MiR-144 injection had no effect on body weight but significantly reduced diethylnitrosamine-induced liver enlargement compared with scrambled microRNA. MiR-144 had no effect on diethylnitrosamine-induced liver tumor number but reduced the tumor size above 50%, as evaluated by magnetic resonance imaging (scrambled microRNA 23.07 ± 5.67 vs miR-144 10.38 ± 2.62, p hepatocellular carcinoma tumorigenesis. Exogenously delivered miR-144 may be a therapeutic strategy to suppress tumor growth in hepatocellular carcinoma.

17-AAG enhances the cytotoxicity of flavopiridol in mantle cell lymphoma via autophagy suppression.

Science.gov (United States)

Xiao, Y; Guan, J

2015-01-01

Flavopiridol, a cyclin-dependent kinase inhibitor (CDKI), shows promising anti-tumor activity in hematologic malignancies. However, Flavopiridol-induced protective autophagy may lead to drug resistance. Here we found that Hsp90 inhibitor 17-AAG can sensitize mantle cell lymphoma (MCL) cells to flavopiridol by suppressing flavopiridol-triggered protective autophagy. The suppressing effect of 17-AAG on autophgy was mediated by Beclin1 degradation and ERK inactivation. Furthermore, 17-AAG enhanced flavopiridol-induced apoptosis and growth suppression in MCL cells. Our study may provide some insights into CDKI -targeted chemotherapies.

Spinal tumors

International Nuclear Information System (INIS)

Goethem, J.W.M. van; Hauwe, L. van den; Oezsarlak, Oe.; Schepper, A.M.A. de; Parizel, P.M.

2004-01-01

Spinal tumors are uncommon lesions but may cause significant morbidity in terms of limb dysfunction. In establishing the differential diagnosis for a spinal lesion, location is the most important feature, but the clinical presentation and the patient's age and gender are also important. Magnetic resonance (MR) imaging plays a central role in the imaging of spinal tumors, easily allowing tumors to be classified as extradural, intradural-extramedullary or intramedullary, which is very useful in tumor characterization. In the evaluation of lesions of the osseous spine both computed tomography (CT) and MR are important. We describe the most common spinal tumors in detail. In general, extradural lesions are the most common with metastasis being the most frequent. Intradural tumors are rare, and the majority is extramedullary, with meningiomas and nerve sheath tumors being the most frequent. Intramedullary tumors are uncommon spinal tumors. Astrocytomas and ependymomas comprise the majority of the intramedullary tumors. The most important tumors are documented with appropriate high quality CT or MR images and the characteristics of these tumors are also summarized in a comprehensive table. Finally we illustrate the use of the new World Health Organization (WHO) classification of neoplasms affecting the central nervous system

Molecular Checkpoint Decisions Made by Subverted Vascular Niche Transform Indolent Tumor Cells into Chemoresistant Cancer Stem Cells.

Science.gov (United States)

Cao, Zhongwei; Scandura, Joseph M; Inghirami, Giorgio G; Shido, Koji; Ding, Bi-Sen; Rafii, Shahin

2017-01-09

Tumor-associated endothelial cells (TECs) regulate tumor cell aggressiveness. However, the core mechanism by which TECs confer stem cell-like activity to indolent tumors is unknown. Here, we used in vivo murine and human tumor models to identify the tumor-suppressive checkpoint role of TEC-expressed insulin growth factor (IGF) binding protein-7 (IGFBP7/angiomodulin). During tumorigenesis, IGFBP7 blocks IGF1 and inhibits expansion and aggresiveness of tumor stem-like cells (TSCs) expressing IGF1 receptor (IGF1R). However, chemotherapy triggers TECs to suppress IGFBP7, and this stimulates IGF1R + TSCs to express FGF4, inducing a feedforward FGFR1-ETS2 angiocrine cascade that obviates TEC IGFBP7. Thus, loss of IGFBP7 and upregulation of IGF1 activates the FGF4-FGFR1-ETS2 pathway in TECs and converts naive tumor cells to chemoresistant TSCs, thereby facilitating their invasiveness and progression. Copyright © 2017 Elsevier Inc. All rights reserved.

Fat suppression applied to MR imaging of the pathologic orbit

International Nuclear Information System (INIS)

Simon, J.H.; Kido, D.K.; Ekholm, S.E.; Totterman, S.; Szumowski, J.; Manzione, J.V. Jr.; Joy, S.E.

1987-01-01

Previous MR studies of the normal orbit have shown that fat suppression sequences applied at the proper T1-T2 weighting will decrease artifacts from chemical shift, and can be used to enhance contrast in selected anatomic regions. The purpose of this study was to evaluate the clinical application of fat suppression to studies of the pathologic orbit. The studies included conventional imaging sequences and comparative fat suppression sequences through a range of T1-T2 weighting (repetition time [TR] 400 msec, echo time [TE]20 msec, to TR 2,000 msec, TE 90 msec), using the chopper fat suppression technique developed by J. Szumowski and D. Plewes, which requires no postprocessing and no increased scan time to achieve relatively linear fat suppression. Fat suppression was advantageous in determining tumor margins (extension through sclera); increasing diagnostic specificity (fat vs. water content); detailing anatomic relationships along bony margins (particularly in the orbital apex); and for demonstrating true thickness of optic nerve separate from adjacent cerebrospinal fluid and fibrous sheath. Disadvantages included susceptibility to motion artifact and a perception of lower quality due to lower overall orbital signal

Video-rate resonant scanning multiphoton microscopy: An emerging technique for intravital imaging of the tumor microenvironment

OpenAIRE

Kirkpatrick, Nathaniel D.; Chung, Euiheon; Cook, Daniel C.; Han, Xiaoxing; Gruionu, Gabriel; Liao, Shan; Munn, Lance L.; Padera, Timothy P.; Fukumura, Dai; Jain, Rakesh K.

2012-01-01

The abnormal tumor microenvironment fuels tumor progression, metastasis, immune suppression, and treatment resistance. Over last several decades, developments in and applications of intravital microscopy have provided unprecedented insights into the dynamics of the tumor microenvironment. In particular, intravital multiphoton microscopy has revealed the abnormal structure and function of tumor-associated blood and lymphatic vessels, the role of aberrant tumor matrix in drug delivery, invasion...

NKT cells as an ideal anti-tumor immunotherapeutic.

Science.gov (United States)

Fujii, Shin-Ichiro; Shimizu, Kanako; Okamoto, Yoshitaka; Kunii, Naoki; Nakayama, Toshinori; Motohashi, Shinichiro; Taniguchi, Masaru

2013-12-02

Human natural killer T (NKT) cells are characterized by their expression of an invariant T cell antigen receptor α chain variable region encoded by a Vα24Jα18 rearrangement. These NKT cells recognize α-galactosylceramide (α-GalCer) in conjunction with the MHC class I-like CD1d molecule and bridge the innate and acquired immune systems to mediate efficient and augmented immune responses. A prime example of one such function is adjuvant activity: NKT cells augment anti-tumor responses because they can rapidly produce large amounts of IFN-γ, which acts on NK cells to eliminate MHC negative tumors and also on CD8 cytotoxic T cells to kill MHC positive tumors. Thus, upon administration of α-GalCer-pulsed DCs, both MHC negative and positive tumor cells can be effectively eliminated, resulting in complete tumor eradication without tumor recurrence. Clinical trials have been completed in a cohort of 17 patients with advanced non-small cell lung cancers and 10 cases of head and neck tumors. Sixty percent of advanced lung cancer patients with high IFN-γ production had significantly prolonged median survival times of 29.3 months with only the primary treatment. In the case of head and neck tumors, 10 patients who completed the trial all had stable disease or partial responses 5 weeks after the combination therapy of α-GalCer-DCs and activated NKT cells. We now focus on two potential powerful treatment options for the future. One is to establish artificial adjuvant vector cells containing tumor mRNA and α-GalCer/CD1d. This stimulates host NKT cells followed by DC maturation and NK cell activation but also induces tumor-specific long-term memory CD8 killer T cell responses, suppressing tumor metastasis even 1 year after the initial single injection. The other approach is to establish induced pluripotent stem (iPS) cells that can generate unlimited numbers of NKT cells with adjuvant activity. Such iPS-derived NKT cells produce IFN-γ in vitro and in vivo upon

Immune Suppression in Tumors as a Surmountable Obstacle to Clinical Efficacy of Cancer Vaccines

International Nuclear Information System (INIS)

Wieërs, Grégoire; Demotte, Nathalie; Godelaine, Danièle; Bruggen, Pierre van der

2011-01-01

Human tumors are usually not spontaneously eliminated by the immune system and therapeutic vaccination of cancer patients with defined antigens is followed by tumor regressions only in a small minority of the patients. The poor vaccination effectiveness could be explained by an immunosuppressive tumor microenvironment. Because T cells that infiltrate tumor metastases have an impaired ability to lyse target cells or to secrete cytokine, many researchers are trying to decipher the underlying immunosuppressive mechanisms. We will review these here, in particular those considered as potential therapeutic targets. A special attention will be given to galectins, a family of carbohydrate binding proteins. These lectins have often been implicated in inflammation and cancer and may be useful targets for the development of new anti-cancer therapies

Cushing Syndrome in a 6-Month-Old Infant due to Adrenocortical Tumor

Directory of Open Access Journals (Sweden)

Volmar KeithE

2009-09-01

Full Text Available Cushing syndrome is rare in infancy and usually due to an adrenocortical tumor (ACT. We report an infant with Cushing syndrome due to adrenocortical carcinoma. The patient presented at six months of age with a three-month history of growth failure, rapid weight gain, acne, and irritability. Physical examination showed obesity, hypertension, and Cushingoid features. Biochemical evaluation showed very high serum cortisol, mildly elevated testosterone, and suppressed ACTH. Abdominal MRI revealed a heterogeneous right adrenal mass extending into the inferior vena cava. Evaluation for metastases was negative. The tumor was removed surgically en bloc. Pathologic examination demonstrated low mitotic rate, but capsular and vascular invasion. She received no adjuvant therapy. Her linear growth has improved and Cushingoid features resolved. Hormonal markers and quarterly PET scans have been negative for recurrence 24 months postoperatively. In conclusion, adrenocortical neoplasms in children are rare, but should be considered in the differential diagnosis of Cushing syndrome.

HAMLET (human alpha-lactalbumin made lethal to tumor cells) triggers autophagic tumor cell death.

Science.gov (United States)

Aits, Sonja; Gustafsson, Lotta; Hallgren, Oskar; Brest, Patrick; Gustafsson, Mattias; Trulsson, Maria; Mossberg, Ann-Kristin; Simon, Hans-Uwe; Mograbi, Baharia; Svanborg, Catharina

2009-03-01

HAMLET, a complex of partially unfolded alpha-lactalbumin and oleic acid, kills a wide range of tumor cells. Here we propose that HAMLET causes macroautophagy in tumor cells and that this contributes to their death. Cell death was accompanied by mitochondrial damage and a reduction in the level of active mTOR and HAMLET triggered extensive cytoplasmic vacuolization and the formation of double-membrane-enclosed vesicles typical of macroautophagy. In addition, HAMLET caused a change from uniform (LC3-I) to granular (LC3-II) staining in LC3-GFP-transfected cells reflecting LC3 translocation during macroautophagy, and this was blocked by the macroautophagy inhibitor 3-methyladenine. HAMLET also caused accumulation of LC3-II detected by Western blot when lysosomal degradation was inhibited suggesting that HAMLET caused an increase in autophagic flux. To determine if macroautophagy contributed to cell death, we used RNA interference against Beclin-1 and Atg5. Suppression of Beclin-1 and Atg5 improved the survival of HAMLET-treated tumor cells and inhibited the increase in granular LC3-GFP staining. The results show that HAMLET triggers macroautophagy in tumor cells and suggest that macroautophagy contributes to HAMLET-induced tumor cell death.

Metastasis genetics, epigenetics, and the tumor microenvironment

Science.gov (United States)

KISS1 is a member of a family of genes known as metastasis suppressors, defined by their ability to block metastasis without blocking primary tumor development and growth. KISS1 re-expression in multiple metastatic cell lines of diverse cellular origin suppresses metastasis; yet, still allows comple...

Activated T cells sustain myeloid-derived suppressor cell-mediated immune suppression

Science.gov (United States)

Damuzzo, Vera; Francescato, Samuela; Pozzuoli, Assunta; Berizzi, Antonio; Mocellin, Simone; Rossi, Carlo Riccardo; Bronte, Vincenzo; Mandruzzato, Susanna

2016-01-01

The expansion of myeloid derived suppressor cells (MDSCs), a suppressive population able to hamper the immune response against cancer, correlates with tumor progression and overall survival in several cancer types. We have previously shown that MDSCs can be induced in vitro from precursors present in the bone marrow and observed that these cells are able to actively proliferate in the presence of activated T cells, whose activation level is critical to drive the suppressive activity of MDSCs. Here we investigated at molecular level the mechanisms involved in the interplay between MDSCs and activated T cells. We found that activated T cells secrete IL-10 following interaction with MDSCs which, in turn, activates STAT3 phosphorylation on MDSCs then leading to B7-H1 expression. We also demonstrated that B7-H1+ MDSCs are responsible for immune suppression through a mechanism involving ARG-1 and IDO expression. Finally, we show that the expression of ligands B7-H1 and MHC class II both on in vitro-induced MDSCs and on MDSCs in the tumor microenvironment of cancer patients is paralleled by an increased expression of their respective receptors PD-1 and LAG-3 on T cells, two inhibitory molecules associated with T cell dysfunction. These findings highlight key molecules and interactions responsible for the extensive cross-talk between MDSCs and activated T cells that are at the basis of immune suppression. PMID:26700461

Explicit hypoxia targeting with tumor suppression by creating an “obligate” anaerobic Salmonella Typhimurium strain

Science.gov (United States)

Yu, Bin; Yang, Mei; Shi, Lei; Yao, Yandan; Jiang, Qinqin; Li, Xuefei; Tang, Lei-Han; Zheng, Bo-Jian; Yuen, Kwok-Yung; Smith, David K.; Song, Erwei; Huang, Jian-Dong

2012-01-01

Using bacteria as therapeutic agents against solid tumors is emerging as an area of great potential in the treatment of cancer. Obligate and facultative anaerobic bacteria have been shown to infiltrate the hypoxic regions of solid tumors, thereby reducing their growth rate or causing regression. However, a major challenge for bacterial therapy of cancer with facultative anaerobes is avoiding damage to normal tissues. Consequently the virulence of bacteria must be adequately attenuated for therapeutic use. By placing an essential gene under a hypoxia conditioned promoter, Salmonella Typhimurium strain SL7207 was engineered to survive only in anaerobic conditions (strain YB1) without otherwise affecting its functions. In breast tumor bearing nude mice, YB1 grew within the tumor, retarding its growth, while being rapidly eliminated from normal tissues. YB1 provides a safe bacterial vector for anti-tumor therapies without compromising the other functions or tumor fitness of the bacterium as attenuation methods normally do. PMID:22666539

Fat suppression MR imaging of sellar and parasellar lesions. The usefulness of the fat-saturation (FATSAT) technique

International Nuclear Information System (INIS)

Isoda, Haruo; Masui, Takayuki; Mochizuki, Takao; Ushimi, Takashi; Takahashi, Motoichiro; Kaneko, Masao; Ohta, Atsuko; Shirakawa, Toyomi; Takizawa, Osamu.

1994-01-01

The purpose of this study was to investigate the utility of fat suppression T 1 -weighted MR images using a frequency-selective presaturation pulse when evaluating the pituitary gland and parasellar lesions. Conventional spin echo T 1 weighted images and fat suppression spin echo T 1 -weighted images were obtained in twenty-three patients with clinically suspected pituitary gland diseases or parasellar lesions using a 1.5T superconductive MR imager with a head coil. Both conventional T 1 -weighted images and fat suppression T 1 -weighted images of the pituitary anterior lobe, posterior lobe, pituitary stalk and pituitary tumors were compared by two radiologists. The visibility of the anterior lobe, posterior lobe, pituitary stalk and pituitary tumors on fat suppression T 1 -weighted images was equal to or better than that on conventional T 1 -weighted images. After the intravenous administration of Gd-DTPA, both imaging methods showed little difference in the visibility of the posterior lobe and pituitary stalk. In conclusion, fat suppression T 1 -weighted images using a frequency-selective presaturation pulse can be useful in evaluating the pituitary gland and parasellar lesions. (author)

Human recombinant interleukin-1 beta- and tumor necrosis factor alpha-mediated suppression of heparin-like compounds on cultured porcine aortic endothelial cells

International Nuclear Information System (INIS)

Kobayashi, M.; Shimada, K.; Ozawa, T.

1990-01-01

Cytokines are known to tip the balance of the coagulant-anticoagulant molecules on the endothelial cell surface toward intravascular coagulation. Their effects on endothelial cell surface-associated heparin-like compounds have not been examined yet. Incorporation of [35S]sulfate into heparan sulfate on cultured porcine aortic endothelial cells was suppressed by human recombinant interleukin-1 beta (rIL-1 beta) or tumor necrosis factor alpha (rTNF alpha) in a dose- and time-dependent manner with little effect on cell number, protein content, and [3H]leucine incorporation of cells. Maximal inhibition was achieved by incubation of cells with 100 ng/ml of rIL-1 beta or 5 ng/ml of rTNF alpha for 12-24 hours, resulting in a reduction of the synthesis of heparan sulfate on the cell surface by approximately 50%. The dose dependency was consistent with that seen in the stimulation of endothelial cell procoagulant activity by each cytokine. The suppression of heparan sulfate synthesis was sustained for at least 48 hours after pretreatment of cells with cytokines and was unchanged after the addition of indomethacin or polymyxin B. The rate of degradation of prelabeled 35S-heparan sulfate on the cell surface was not altered by cytokine treatments. Neither the size, the net negative charge, nor the proportion of the molecule with high affinity for antithrombin III of endothelial cell heparan sulfate was changed by cytokines. Furthermore, specific binding of 125I-labeled antithrombin III to the endothelial cell surface was reduced to 40-60% of control by cytokines. In parallel with reduction in binding, antithrombin III cofactor activity was partially diminished in cytokine-treated endothelial cells. Thus, cytokine-mediated suppression of heparin-like substance on endothelial cells appears to be another cytokine-inducible endothelial effects affecting coagulation

Dioscin inhibits colon tumor growth and tumor angiogenesis through regulating VEGFR2 and AKT/MAPK signaling pathways

Energy Technology Data Exchange (ETDEWEB)

Tong, Qingyi [Regenerative Medicine Research Center, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041 (China); Qing, Yong, E-mail: qingyongxy@yahoo.co.jp [Department of Pharmacology, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan 610041 (China); Wu, Yang [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041 (China); Hu, Xiaojuan; Jiang, Lei [Department of Pharmacology, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan 610041 (China); Wu, Xiaohua, E-mail: wuxh@scu.edu.cn [Regenerative Medicine Research Center, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041 (China)

2014-12-01

Dioscin has shown cytotoxicity against cancer cells, but its in vivo effects and the mechanisms have not elucidated yet. The purpose of the current study was to assess the antitumor effects and the molecular mechanisms of dioscin. We showed that dioscin could inhibit tumor growth in vivo and has no toxicity at the test condition. The growth suppression was accompanied by obvious blood vessel decrease within solid tumors. We also found dioscin treatment inhibited the proliferation of cancer and endothelial cell lines, and most sensitive to primary cultured human umbilical vein endothelial cells (HUVECs). What's more, analysis of HUVECs migration, invasion, and tube formation exhibited that dioscin has significantly inhibitive effects to these actions. Further analysis of blood vessel formation in the matrigel plugs indicated that dioscin could inhibit VEGF-induced blood vessel formation in vivo. We also identified that dioscin could suppress the downstream protein kinases of VEGFR2, including Src, FAK, AKT and Erk1/2, accompanied by the increase of phosphorylated P38MAPK. The results potently suggest that dioscin may be a potential anticancer drug, which efficiently inhibits angiogenesis induced by VEGFR2 signaling pathway as well as AKT/MAPK pathways. - Highlights: • Dioscin inhibits tumor growth in vivo and does not exhibit any toxicity. • Dioscin inhibits angiogenesis within solid tumors. • Dioscin inhibits the proliferation, migration, invasion, and tube formation of HUVECs. • Dioscin inhibits VEGF–induced blood vessel formation in vivo. • Dioscin inhibits VEGFR2 signaling pathway as well as AKT/MAPK pathway.

Own-race and own-age biases facilitate visual awareness of faces under interocular suppression

Directory of Open Access Journals (Sweden)

Timo eStein

2014-08-01

Full Text Available The detection of a face in a visual scene is the first stage in the face processing hierarchy. Although all subsequent, more elaborate face processing depends on the initial detection of a face, surprisingly little is known about the perceptual mechanisms underlying face detection. Recent evidence suggests that relatively hard-wired face detection mechanisms are broadly tuned to all face-like visual patterns as long as they respect the typical spatial configuration of the eyes above the mouth. Here, we qualify this notion by showing that face detection mechanisms are also sensitive to face shape and facial surface reflectance properties. We used continuous flash suppression (CFS to render faces invisible at the beginning of a trial and measured the time upright and inverted faces needed to break into awareness. Young Caucasian adult observers were presented with faces from their own race or from another race (race experiment and with faces from their own age group or from another age group (age experiment. Faces matching the observers’ own race and age group were detected more quickly. Moreover, the advantage of upright over inverted faces in overcoming CFS, i.e. the face inversion effect, was larger for own-race and own-age faces. These results demonstrate that differences in face shape and surface reflectance influence access to awareness and configural face processing at the initial detection stage. Although we did not collect data from observers of another race or age group, these findings are a first indication that face detection mechanisms are shaped by visual experience with faces from one’s own social group. Such experience-based fine-tuning of face detection mechanisms may equip in-group faces with a competitive advantage for access to conscious awareness.

Wilms tumors: genotypes and phenotypes

NARCIS (Netherlands)

H. Segers (Heidi)

2013-01-01

textabstractWilms tumor, or nephroblastoma, represents about 90% of all pediatric renal tumors and about 7% of all pediatric malignancies. Most Wilms tumors are unilateral, although in 5-10 % of the patients both kidneys are infected. Wilms tumor typically occurs between the age of 2 and 4 years,

Blocking the chaperone kinome pathway: Mechanistic insights into a novel dual inhibition approach for supra-additive suppression of malignant tumors

Energy Technology Data Exchange (ETDEWEB)

Grover, Abhinav [Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016 (India); Shandilya, Ashutosh [Supercomputing Facility for Bioinformatics and Computational Biology, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016 (India); Agrawal, Vibhuti; Pratik, Piyush; Bhasme, Divya; Bisaria, Virendra S. [Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016 (India); Sundar, Durai, E-mail: sundar@dbeb.iitd.ac.in [Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016 (India)

2011-01-07

Research highlights: {yields} Withaferin A and 17-DMAG synergistically inhibit the Hsp90-Cdc37 chaperone pair. {yields} Binding of WA to Cdc37 cleft suppresses its kinase binding activity. {yields} 17-DMAG binding to the association complex results in H-bonds with 60% clustering. {yields} The ligands' bound complex was found structurally and thermodynamically stable. -- Abstract: The chaperone Hsp90 is involved in regulating the stability and activation state of more than 200 'client' proteins and takes part in the cancer diseased states. The major clientele-protein kinases depend on Hsp90 for their proper folding and functioning. Cdc37, a kinase targeting co-chaperone of Hsp90, mediates the interactions between Hsp90 and protein kinases. Targeting of Cdc37 has the prospect of delivering predominantly kinase-selective molecular responses as compared to the current pharmacologic Hsp90 inhibitors. The present work reports a bio-computational study carried out with the aim of exploring the dual inhibition of Hsp90/Cdc37 chaperone/co-chaperone association complex by the naturally occurring drug candidates withaferin A and 17-DMAG along with their possible modes of action. Our molecular docking studies reveal that withaferin A in combination with 17-DMAG can act as potent chaperone system inhibitors. The structural and thermodynamic stability of the ligands' bound complex was also observed from molecular dynamics simulations in water. Our results suggest a novel tumor suppressive action mechanism of herbal ligands which can be looked forward for further clinical investigations for possible anticancer drug formulations.

Taming dendritic cells with TIM-3: another immunosuppressive strategy used by tumors.

Science.gov (United States)

Patel, Jaina; Bozeman, Erica N; Selvaraj, Periasamy

2012-12-01

Evaluation of: Chiba S, Baghdadi M, Akiba H et al. Tumor-infiltrating DCs suppress nucleic acid-mediated innate immune responses through interactions between the receptor TIM-3 and the alarmin HMGB1. Nat. Immunol. 13, 832-842 (2012). The identification of TIM-3 expression on tumor-associated dendritic cells (TADCs) provides insight into another aspect of tumor-mediated immunosuppression. The role of TIM-3 has been well characterized on tumor-infiltrating T cells; however, its role on TADCs was not previously known. The current paper demonstrated that TIM-3 was predominantly expressed by TADCs and its interaction with the nuclear protein HMGB1 suppressed nucleic acid-mediated activation of an effective antitumor immune response. The authors were able to show that TIM-3 interaction with HMGB1 prevented the localization of nucleic acids into endosomal vesicles. Furthermore, chemotherapy was found to be more effective in anti-TIM-3 monoclonal antibody-treated mice or mice depleted of all DCs, which indicated that a significant role is played by TADCs in inhibiting tumor regression. Taken together, these findings identify TIM-3 as a potential target for inducing antitumor immunity in conjunction with DNA vaccines and/or immunogenic chemotherapy in clinical settings.

Clinical evaluation of fat suppressed fast-SPGR sequence of the breast MR imaging

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Mitsuyuki; Hasegawa, Makoto; Matsubara, Tadashi [Yokohama Sakae Kyosai Hospital (Japan)

1998-05-01

MR-mammography by fat suppressed Fast-SPGR was evaluated for diagnosis and determination of invasion of tumor. Dynamic MRIs were performed in 12 phases, such as, before infusion of contrast media, right after and one to ten minutes after infusion with interval of one minute. In 15 patients (breast cancer, fibroadenoma, lymphocytic lobulitits and cystic intraductal papilloma), underwent MRI, the images were compared with pathological findings. Ten cases were confirmed as malignancy among 11 cases of breast cancer (sensitivity 91%). Eleven cases were confirmed as breast cancer among 12 cases diagnosed as breast cancer by MRI (specificity 92%). In 12 of all 15 cases, benignity or malignancy was checked correctly (accuracy 80%). Invasion of breast cancer was defined as the deep color dyeing area which was neighbored with the tumor in early stage of cystography. Eight of 11 cases were diagnosed precisely with fat suppression image, and nine were by subtraction image. Diagnosis was possible only by subtraction image in a case of scirrhous carcinoma accompanied with intradutal invasion. The area of invasion was not defined correctly in the case accompanied by mastopathy. It is difficult to evaluate benignity or malignancy of mammary gland tumor only by dynamic MRI, it is necessary to diagnose the shape and deep color image of tumor generally. (K.H.)

The Quest for the 1p36 Tumor Suppressor

Science.gov (United States)

Bagchi, Anindya; Mills, Alea A.

2010-01-01

Genomic analyses of late-stage human cancers have uncovered deletions encompassing 1p36, thereby providing an extensive body of literature supporting the idea that a potent tumor suppressor resides in this interval. Although a number of genes have been proposed as 1p36 candidate tumor suppressors, convincing evidence that their encoded products protect from cancer has been scanty. A recent functional study identified CHD5 as a novel tumor suppressor mapping to 1p36. Here we discuss evidence supporting CHD5’s tumor suppressive role. Together, these findings suggest that strategies designed to enhance CHD5 activity could provide novel approaches for treating a broad range of human malignancies. PMID:18413720

Kurarinol induces hepatocellular carcinoma cell apoptosis through suppressing cellular signal transducer and activator of transcription 3 signaling

International Nuclear Information System (INIS)

Shu, Guangwen; Yang, Jing; Zhao, Wenhao; Xu, Chan; Hong, Zongguo; Mei, Zhinan; Yang, Xinzhou

2014-01-01

Kurarinol is a flavonoid isolated from roots of the medical plant Sophora flavescens. However, its cytotoxic activity against hepatocellular carcinoma (HCC) cells and toxic effects on mammalians remain largely unexplored. Here, the pro-apoptotic activities of kurarinol on HCC cells and its toxic impacts on tumor-bearing mice were evaluated. The molecular mechanisms underlying kurarinol-induced HCC cell apoptosis were also investigated. We found that kurarinol dose-dependently provoked HepG2, Huh-7 and H22 HCC cell apoptosis. In addition, kurarinol gave rise to a considerable decrease in the transcriptional activity of signal transducer and activator of transcription 3 (STAT3) in HCC cells. Suppression of STAT3 signaling is involved in kurarinol-induced HCC cell apoptosis. In vivo studies showed that kurarinol injection substantially induced transplanted H22 cell apoptosis with low toxic impacts on tumor-bearing mice. Similarly, the transcriptional activity of STAT3 in transplanted tumor tissues was significantly suppressed after kurarinol treatment. Collectively, our current research demonstrated that kurarinol has the capacity of inducing HCC cell apoptosis both in vitro and in vivo with undetectable toxic impacts on the host. Suppressing STAT3 signaling is implicated in kurarinol-mediated HCC cell apoptosis. - Highlights: • Kurarinol induces hepatocellular carcinoma (HCC) cell apoptosis. • Kurarinol induces HCC cell apoptosis via inhibiting STAT3. • Kurarinol exhibits low toxic effects on tumor-bearing animals

HBV-specific CD4+ cytotoxic T cells in hepatocellular carcinoma are less cytolytic toward tumor cells and suppress CD8+ T cell-mediated antitumor immunity.

Science.gov (United States)

Meng, Fanzhi; Zhen, Shoumei; Song, Bin

2017-08-01

In East Asia and sub-Saharan Africa, chronic infection is the main cause of the development of hepatocellular carcinoma, an aggressive cancer with low survival rate. Cytotoxic T cell-based immunotherapy is a promising treatment strategy. Here, we investigated the possibility of using HBV-specific CD4 + cytotoxic T cells to eliminate tumor cells. The naturally occurring HBV-specific cytotoxic CD4 + and CD8 + T cells were identified by HBV peptide pool stimulation. We found that in HBV-induced hepatocellular carcinoma patients, the HBV-specific cytotoxic CD4 + T cells and cytotoxic CD8 + T cells were present at similar numbers. But compared to the CD8 + cytotoxic T cells, the CD4 + cytotoxic T cells secreted less cytolytic factors granzyme A (GzmA) and granzyme B (GzmB), and were less effective at eliminating tumor cells. In addition, despite being able to secrete cytolytic factors, CD4 + T cells suppressed the cytotoxicity mediated by CD8 + T cells, even when CD4 + CD25 + regulator T cells were absent. Interestingly, we found that interleukin 10 (IL-10)-secreting Tr1 cells were enriched in the cytotoxic CD4 + T cells. Neutralization of IL-10 abrogated the suppression of CD8 + T cells by CD4 + CD25 - T cells. Neither the frequency nor the absolute number of HBV-specific CD4 + cytotoxic T cells were correlated with the clinical outcome of advanced stage hepatocellular carcinoma patients. Together, this study demonstrated that in HBV-related hepatocellular carcinoma, CD4 + T cell-mediated cytotoxicity was present naturally in the host and had the potential to exert antitumor immunity, but its capacity was limited and was associated with immunoregulatory properties. © 2017 APMIS. Published by John Wiley & Sons Ltd.

Voluntary Running Suppresses Tumor Growth through Epinephrine- and IL-6-Dependent NK Cell Mobilization and Redistribution

DEFF Research Database (Denmark)

Pedersen, Line; Idorn, Manja; Olofsson, Gitte H.

2016-01-01

Regular exercise reduces the risk of cancer and disease recurrence. Yet the mechanisms behind this protection remain to be elucidated. In this study, tumor-bearing mice randomized to voluntary wheel running showed over 60% reduction in tumor incidence and growth across five different tumor models....... Microarray analysis revealed training-induced upregulation of pathways associated with immune function. NK cell infiltration was significantly increased in tumors from running mice, whereas depletion of NK cells enhanced tumor growth and blunted the beneficial effects of exercise. Mechanistic analyses showed...

Maximizing Tumor Immunity With Fractionated Radiation

International Nuclear Information System (INIS)

Schaue, Dörthe; Ratikan, Josephine A.; Iwamoto, Keisuke S.; McBride, William H.

2012-01-01

Purpose: Technologic advances have led to increased clinical use of higher-sized fractions of radiation dose and higher total doses. How these modify the pathways involved in tumor cell death, normal tissue response, and signaling to the immune system has been inadequately explored. Here we ask how radiation dose and fraction size affect antitumor immunity, the suppression thereof, and how this might relate to tumor control. Methods and Materials: Mice bearing B16-OVA murine melanoma were treated with up to 15 Gy radiation given in various-size fractions, and tumor growth followed. The tumor-specific immune response in the spleen was assessed by interferon-γ enzyme-linked immunospot (ELISPOT) assay with ovalbumin (OVA) as the surrogate tumor antigen and the contribution of regulatory T cells (Tregs) determined by the proportion of CD4 + CD25 hi Foxp3 + T cells. Results: After single doses, tumor control increased with the size of radiation dose, as did the number of tumor-reactive T cells. This was offset at the highest dose by an increase in Treg representation. Fractionated treatment with medium-size radiation doses of 7.5 Gy/fraction gave the best tumor control and tumor immunity while maintaining low Treg numbers. Conclusions: Radiation can be an immune adjuvant, but the response varies with the size of dose per fraction. The ultimate challenge is to optimally integrate cancer immunotherapy into radiation therapy.

Milk fat globule membrane supplementation with voluntary running exercise attenuates age-related motor dysfunction by suppressing neuromuscular junction abnormalities in mice.

Science.gov (United States)

Yano, Michiko; Minegishi, Yoshihiko; Sugita, Satoshi; Ota, Noriyasu

2017-10-15

Age-related loss of skeletal muscle mass and function attenuates physical performance, and maintaining fine muscle innervation is known to play an important role in its prevention. We had previously shown that consumption of milk fat globule membrane (MFGM) with habitual exercise improves the muscle mass and motor function in humans and mice. Improvement of neuromuscular junction (NMJ) was suggested as one of the mechanisms underlying these effects. In this study, we evaluated the effect of MFGM intake combined with voluntary running (MFGM-VR) on morphological changes of NMJ and motor function in aging mice. Seven months following the intervention, the MFGM-VR group showed a significantly improved motor coordination in the rotarod test and muscle force in the grip strength test compared with the control group at 13 and 14months of age, respectively. In 14-month old control mice, the extensor digitorum longus muscle showed increased abnormal NMJs, such as fragmentation and denervation, compared with 6-month old young mice. However, such age-related deteriorations of NMJs were significantly suppressed in the MFGM-VR group. Increase in the expression of NMJ formation-related genes, such as agrin and LDL Receptor Related Protein 4 (LRP4), might contribute to this beneficial effect. Rotarod performance and grip strength showed significant negative correlation with the status of denervation and fragmentation of NMJs. These results suggest that MFGM intake with voluntary running exercise effectively suppresses age-related morphological deterioration of NMJ, thus contributing to improvement of motor function. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Fenofibrate suppressed proliferation and migration of human neuroblastoma cells via oxidative stress dependent of TXNIP upregulation

Energy Technology Data Exchange (ETDEWEB)

Su, Cunjin; Shi, Aiming; Cao, Guowen [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Tao, Tao [Department of Urology, Zhongda Hospital, Medical School of Southeast University, Nanjing, 210009 (China); Chen, Ruidong [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Hu, Zhanhong; Shen, Zhu; Tao, Hong; Cao, Bin [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Hu, Duanmin, E-mail: hudmsdfey@sina.com [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Bao, Junjie, E-mail: baojjsdfey@sina.com [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China)

2015-05-15

There are no appropriate drugs for metastatic neuroblastoma (NB), which is the most common extra-cranial solid tumor for childhood. Thioredoxin binding protein (TXNIP), the endogenous inhibitor of ROS elimination, has been identified as a tumor suppressor in various solid tumors. It reported that fenofibrate exerts anti-tumor effects in several human cancer cell lines. However, its detail mechanisms remain unclear. The present study assessed the effects of fenofibrate on NB cells and investigated TXNIP role in its anti-tumor mechanisms. We used MTT assay to detect cells proliferation, starch wound test to investigate cells migration, H{sub 2}DCF-DA to detect intracellular ROS, siRNA to interfere TXNIP and peroxisome proliferator-androgen receptor-alpha (PPAR-α) expression, western blot to determine protein levels, flow cytometry to analyze apoptosis. Fenofibrate suppressed proliferation and migration of NB cells, remarkably increased intracellular ROS, upregulated TXNIP expression, promoted cell apoptosis. Furthermore, inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. Our results indicated the anti-tumor role of fenofibrate on NB cells by exacerbating oxidative stress and inducing apoptosis was dependent on the upregulation of TXNIP. - Highlights: • We found that fenofibrate suppressed proliferation and migration of NB cells. • We found that fenofibrate remarkably increased intracellular ROS, upregulated TXNIP expression, and promoted cell apoptosis. • Inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. • Our results indicated the anti-tumor role of fenofibrate on NB cells was dependent on the upregulation of TXNIP.

Prdm5 suppresses Apc(Min)-driven intestinal adenomas and regulates monoacylglycerol lipase expression

DEFF Research Database (Denmark)

Galli, G G; Multhaupt, H A; Carrara, M

2013-01-01

PRDM proteins are tissue-specific transcription factors often deregulated in diseases, particularly in cancer where different members have been found to act as oncogenes or tumor suppressors. PRDM5 is a poorly characterized member of the PRDM family for which several studies have reported a high ...... PRDM5 target repertoire likely facilitating the tumor-suppressive functions of PRDM5.Oncogene advance online publication, 22 July 2013; doi:10.1038/onc.2013.283....

Reduced miR-433 expression is associated with advanced stages and early relapse of colorectal cancer and restored miR-433 expression suppresses the migration, invasion and proliferation of tumor cells in vitro and in nude mice.

Science.gov (United States)

Zhang, Jian; Zhang, Lei; Zhang, Tong; Dong, Xin-Min; Zhu, Yu; Chen, Long-Hua

2018-05-01

The expression of microRNA (miR-433) is altered in various types of human cancer. The present study analyzed the prognostic and biological value of miR-433 expression in colorectal cancer using reverse transcription-quantitative polymerase chain reaction in 125 colorectal tissue specimens (including a test cohort of 40 cases of paired colorectal cancer and adjacent normal mucosae and a confirmation cohort of 85 cases of stage I-III colorectal cancer). In vitro and nude mouse xenograft experiments were subsequently used to assess the effects of miR-433 expression on the regulation of colorectal cancer cell proliferation, adhesion, migration, and invasion. The data indicated that miR-433 expression was significantly downregulated in colorectal cancer tissues in the test and confirmation patient cohorts and that low miR-433 expression was associated with advanced tumor stage and early relapse. Furthermore, the restoration of miR-433 expression was able to significantly inhibit the proliferation of tumor cells by inducing G1-S cell cycle arrest, suppressing cyclinD1 and CDK4 expression, and markedly inhibited the migratory and invasive capacities of tumor cells in vitro . The restoration of miR-433 expression or liposome-based delivery of miR-433 mimics suppressed the growth of colorectal cancer cell xenografts in nude mice. In conclusion, miR-433 may be a putative tumor suppressor in colorectal cancer, and the detection of low miR-433 expression will be investigated in further studies as a putative biomarker for the detection of early relapse in patients with colorectal cancer.

Explosive mutation accumulation triggered by heterozygous human Pol ε proofreading-deficiency is driven by suppression of mismatch repair

Science.gov (United States)

Campbell, Brittany B; Ungerleider, Nathan; Light, Nicholas; Wu, Tong; LeCompte, Kimberly G; Goksenin, A Yasemin; Bunnell, Bruce A; Tabori, Uri; Shlien, Adam

2018-01-01

Tumors defective for DNA polymerase (Pol) ε proofreading have the highest tumor mutation burden identified. A major unanswered question is whether loss of Pol ε proofreading by itself is sufficient to drive this mutagenesis, or whether additional factors are necessary. To address this, we used a combination of next generation sequencing and in vitro biochemistry on human cell lines engineered to have defects in Pol ε proofreading and mismatch repair. Absent mismatch repair, monoallelic Pol ε proofreading deficiency caused a rapid increase in a unique mutation signature, similar to that observed in tumors from patients with biallelic mismatch repair deficiency and heterozygous Pol ε mutations. Restoring mismatch repair was sufficient to suppress the explosive mutation accumulation. These results strongly suggest that concomitant suppression of mismatch repair, a hallmark of colorectal and other aggressive cancers, is a critical force for driving the explosive mutagenesis seen in tumors expressing exonuclease-deficient Pol ε. PMID:29488881

Rejection of large HPV-16 expressing tumors in aged mice by a single immunization of VacciMax® encapsulated CTL/T helper peptides

Directory of Open Access Journals (Sweden)

MacDonald Lisa

2007-06-01

Full Text Available Abstract The incidence of cancer increases significantly in later life, yet few pre-clinical studies of cancer immunotherapy use mice of advanced age. A novel vaccine delivery platform (VacciMax®,VM is described that encapsulates antigens and adjuvants in multilamellar liposomes in a water-in-oil emulsion. The therapeutic potential of VM-based vaccines administered as a single dose was tested in HLA-A2 transgenic mice of advanced age (48–58 weeks old bearing large palpable TC1/A2 tumors. The VM-based vaccines contained one or more peptides having human CTL epitopes derived from HPV 16 E6 and E7. VM formulations contained a single peptide, a mixture of four peptides or the same four peptides linked together in a single long peptide. All VM formulations contained PADRE and CpG as adjuvants and ISA51 as the hydrophobic component of the water-in-oil emulsion. VM-formulated vaccines containing the four peptides as a mixture or linked together in one long peptide eradicated 19-day old established tumors within 21 days of immunization. Peptide-specific cytotoxic cellular responses were confirmed by ELISPOT and intracellular staining for IFN-γ producing CD8+ T cells. Mice rendered tumor-free by vaccination were re-challenged in the opposite flank with 10 million HLF-16 tumor cells, another HLA-A2/E6/E7 expressing tumor cell line. None of these mice developed tumors following the re-challenge. In summary, this report describes a VM-formulated therapeutic vaccine with the following unprecedented outcome: a eradication of large tumors (> 700 mm3 b in mice of advanced age c in less than three weeks post-immunization d following a single vaccination.

Studies into the transplantation biology of ultraviolet light-induced tumors

International Nuclear Information System (INIS)

Daynes, R.A.; Spellman, C.W.; Woodward, J.G.; Stewart, D.A.

1977-01-01

The majority of skin tumors induced in mice by ultraviolet (uv) light are rejected when implanted into normal syngeneic recipients. Subcarcinogenic levels of uv light exposure render the normally resistant mice susceptible to tumor challenge. The immunoregulatory effect of uv light appears to be additive, since the growth rate of a tumor transplant is dependent upon the length of uv exposure administered prior to implantation. This suppressive influence does not appear to be directly mediated by the uv light, because the amputation of uv-irradiated tail skin allows for a retention of tumor resistance in otherwise tumor-susceptible hosts. uv-irradiated mice could also be immunized against uv tumors, which suggests that immune recognition of tumor-specific transplantation antigens has not been inhibited. The ability of uv exposure to alter normal immunological reactivity to uv-induced tumors is possibly an integral factor in the mechanism underlying uv carcinogenesis

CDB-4124, a progesterone receptor modulator, inhibits mammary carcinogenesis by suppressing cell proliferation and inducing apoptosis.

Science.gov (United States)

Wiehle, Ronald; Lantvit, Daniel; Yamada, Tohru; Christov, Konstantin

2011-03-01

CDB-4124 (Proellex or telapristone acetate) is a modulator of progesterone receptor (PR) signaling, which is currently employed in preclinical studies for prevention and treatment of breast cancer and has been used in clinical studies for treatment of uterine fibroids and endometriosis. Here we provide evidence for its action on steroid hormone-signaling, cell cycle-regulated genes and in vivo on mammary carcinogenesis. When CDB-4124 is given to rats at 200 mg/kg for 24 months, it prevents the development of spontaneous mammary hyperplastic and premalignant lesions. Also, CDB-4124 given as subcutaneous pellets at two different doses suppressed, dose dependently, N-methyl-N-nitrosourea (MNU)-induced mammary carcinogenesis. The high dose (30 mg, over 84 days) increased tumor latency from 66 ± 24 days to 87 ± 20 days (P CDB-4124 inhibited cell proliferation and induced apoptosis in MNU-induced mammary tumors, which correlated with a decreased proportion of PR(+) tumor cells and with decreased serum progesterone. CDB-4124 did not affect serum estradiol. In a mechanistic study employing T47D cells we found that CDB-4124 suppressed G(1)/G(0)-S transition by inhibiting CDK2 and CDK4 expressions, which correlated with inhibition of estrogen receptor (ER) expression. Taken together, these data indicate that CDB-4124 can suppress the development of precancerous lesions and carcinogen-induced ER(+) mammary tumors in rats, and may have implications for prevention and treatment of human breast cancer.

Triparanol suppresses human tumor growth in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Bi, Xinyu [Department of Abdominal Surgical Oncology, Lab of Abdominal Surgical Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021 (China); Han, Xingpeng [Department of Pathology, Tianjin Chest Hospital, Tianjin 300051 (China); Zhang, Fang [Zhejiang Provincial Key Laboratory of Applied Enzymology, Yangtze Delta Region Institute of Tsinghua University, Jiaxing 314006, Zhejiang (China); He, Miao [Life Sciences School, Sun Yat-sen University, Guangzhou 510275 (China); Zhang, Yi [Department of Thoracic Surgery, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Zhi, Xiu-Yi, E-mail: xiuyizhi@yahoo.com.cn [Department of Thoracic Surgery, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Zhao, Hong, E-mail: zhaohong9@sina.com [Department of Abdominal Surgical Oncology, Lab of Abdominal Surgical Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021 (China)

2012-08-31

Highlights: Black-Right-Pointing-Pointer Demonstrate Triparanol can block proliferation in multiple cancer cells. Black-Right-Pointing-Pointer Demonstrate Triparanol can induce apoptosis in multiple cancer cells. Black-Right-Pointing-Pointer Proved Triparanol can inhibit Hedgehog signaling in multiple cancer cells. Black-Right-Pointing-Pointer Demonstrated Triparanol can impede tumor growth in vivo in mouse xenograft model. -- Abstract: Despite the improved contemporary multidisciplinary regimens treating cancer, majority of cancer patients still suffer from adverse effects and relapse, therefore posing a significant challenge to uncover more efficacious molecular therapeutics targeting signaling pathways central to tumorigenesis. Here, our study have demonstrated that Triparanol, a cholesterol synthesis inhibitor, can block proliferation and induce apoptosis in multiple human cancer cells including lung, breast, liver, pancreatic, prostate cancer and melanoma cells, and growth inhibition can be rescued by exogenous addition of cholesterol. Remarkably, we have proved Triparanol can significantly repress Hedgehog pathway signaling in these human cancer cells. Furthermore, study in a mouse xenograft model of human lung cancer has validated that Triparanol can impede tumor growth in vivo. We have therefore uncovered Triparanol as potential new cancer therapeutic in treating multiple types of human cancers with deregulated Hedgehog signaling.

Triparanol suppresses human tumor growth in vitro and in vivo

International Nuclear Information System (INIS)

Bi, Xinyu; Han, Xingpeng; Zhang, Fang; He, Miao; Zhang, Yi; Zhi, Xiu-Yi; Zhao, Hong

2012-01-01

Highlights: ► Demonstrate Triparanol can block proliferation in multiple cancer cells. ► Demonstrate Triparanol can induce apoptosis in multiple cancer cells. ► Proved Triparanol can inhibit Hedgehog signaling in multiple cancer cells. ► Demonstrated Triparanol can impede tumor growth in vivo in mouse xenograft model. -- Abstract: Despite the improved contemporary multidisciplinary regimens treating cancer, majority of cancer patients still suffer from adverse effects and relapse, therefore posing a significant challenge to uncover more efficacious molecular therapeutics targeting signaling pathways central to tumorigenesis. Here, our study have demonstrated that Triparanol, a cholesterol synthesis inhibitor, can block proliferation and induce apoptosis in multiple human cancer cells including lung, breast, liver, pancreatic, prostate cancer and melanoma cells, and growth inhibition can be rescued by exogenous addition of cholesterol. Remarkably, we have proved Triparanol can significantly repress Hedgehog pathway signaling in these human cancer cells. Furthermore, study in a mouse xenograft model of human lung cancer has validated that Triparanol can impede tumor growth in vivo. We have therefore uncovered Triparanol as potential new cancer therapeutic in treating multiple types of human cancers with deregulated Hedgehog signaling.

Epigenetic identification of ZNF545 as a functional tumor suppressor in multiple myeloma via activation of p53 signaling pathway

Energy Technology Data Exchange (ETDEWEB)

Fan, Yu [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Zhan, Qian [The Center for Clinical Molecular Medical Detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Xu, Hongying [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Li, Lili; Li, Chen [Cancer Epigenetics Laboratory, Department of Clinical Oncology, Sir YK Pao Center for Cancer and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong and CUHK Shenzhen Research Institute (Hong Kong); Xiao, Qian; Xiang, Shili; Hui, Tianli [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Xiang, Tingxiu, E-mail: larissaxiang@163.com [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Ren, Guosheng, E-mail: rengs726@126.com [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China)

2016-06-10

The KRAB–zinc-finger protein ZNF545 was recently identified as a potential suppressor gene in several tumors. However, the regulatory mechanisms of ZNF545 in tumorigenesis remain unclear. In this study, we investigated the expression and roles of ZNF545 in multiple myeloma (MM). ZNF545 was frequently downregulated in MM tissues compared with non-tumor bone marrow tissues. ZNF545 expression was silenced by promoter methylation in MM cell lines, and could be restored by demethylation treatment. ZNF545 methylation was detected in 28.3% of MM tissues, compared with 4.3% of normal bone marrow tissues. ZNF545 transcriptionally activated the p53 signaling pathway but had no effect on Akt in MM, whereas ectopic expression of ZNF545 in silenced cells suppressed their proliferation and induced apoptosis. We therefore identified ZNF545 as a novel tumor suppressor inhibiting tumor growth through activation of the p53 pathway in MM. Moreover, tumor-specific methylation of ZNF545 may represent an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. -- Highlights: •Downregulated ZNF545 in MM tissues and cell lines and ectopic expression of ZNF545 suppresses tumor growth. •Tumor-specific methylation of ZNF545 represents an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. •ZNF545 exerts its tumor suppressive effects via transcriptional activating p53 pathway.

Epigenetic identification of ZNF545 as a functional tumor suppressor in multiple myeloma via activation of p53 signaling pathway

International Nuclear Information System (INIS)

Fan, Yu; Zhan, Qian; Xu, Hongying; Li, Lili; Li, Chen; Xiao, Qian; Xiang, Shili; Hui, Tianli; Xiang, Tingxiu; Ren, Guosheng

2016-01-01

The KRAB–zinc-finger protein ZNF545 was recently identified as a potential suppressor gene in several tumors. However, the regulatory mechanisms of ZNF545 in tumorigenesis remain unclear. In this study, we investigated the expression and roles of ZNF545 in multiple myeloma (MM). ZNF545 was frequently downregulated in MM tissues compared with non-tumor bone marrow tissues. ZNF545 expression was silenced by promoter methylation in MM cell lines, and could be restored by demethylation treatment. ZNF545 methylation was detected in 28.3% of MM tissues, compared with 4.3% of normal bone marrow tissues. ZNF545 transcriptionally activated the p53 signaling pathway but had no effect on Akt in MM, whereas ectopic expression of ZNF545 in silenced cells suppressed their proliferation and induced apoptosis. We therefore identified ZNF545 as a novel tumor suppressor inhibiting tumor growth through activation of the p53 pathway in MM. Moreover, tumor-specific methylation of ZNF545 may represent an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. -- Highlights: •Downregulated ZNF545 in MM tissues and cell lines and ectopic expression of ZNF545 suppresses tumor growth. •Tumor-specific methylation of ZNF545 represents an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. •ZNF545 exerts its tumor suppressive effects via transcriptional activating p53 pathway.

Discovery and validation of the tumor-suppressive function of long noncoding RNA PANDA in human diffuse large B-cell lymphoma through the inactivation of MAPK/ERK signaling pathway.

Science.gov (United States)

Wang, Yingjun; Zhang, Mingzhi; Xu, Huanan; Wang, Yifei; Li, Zhaoming; Chang, Yu; Wang, Xinhuan; Fu, Xiaorui; Zhou, Zhiyuan; Yang, Siyuan; Wang, Bei; Shang, Yufeng

2017-09-22

Diffuse large B-cell lymphoma (DLBCL) is one of the leading causes of cancer-related mortality, and responds badly to existing treatment. Thus, it is of urgent need to identify novel prognostic markers and therapeutic targets of DLBCL. Recent studies have shown that long non-coding RNAs (lncRNAs) play an important role in the development of cancer. By using the next generation HiSeq sequencing assay, we determined lncRNAs exhibiting differential expression between DLBCL patients and healthy controls. Then, RT-qPCR was performed for identification in clinical samples and cell materials, and lncRNA PANDA was verified to be down-regulated in DLBCL patients and have considerable diagnostic potential. In addition, decreased serum PANDA level was correlated to poorer clinical outcome and lower overall survival in DLBCL patients. Subsequently, we determined the experimental role of lncRNA PANDA in DLBCL progression. Luciferase reporter assay and chromatin immunoprecipitation assay suggested that lncRNA PANDA was induced by p53 and p53 interacts with the promoter region of PANDA. Cell functional assay further indicated that PANDA functioned as a tumor suppressor gene through the suppression of cell growth by a G0/G1 cell cycle arrest in DLBCL. More importantly, Cignal Signal Transduction Reporter Array and western blot assay showed that lncRNA PANDA inactivated the MAPK/ERK signaling pathway. In conclusion, our integrated approach demonstrates that PANDA in DLBCL confers a tumor suppressive function through inhibiting cell proliferation and silencing MAPK/ERK signaling pathway. Thus, PANDA may be a promising therapeutic target for patients with DLBCL.

Soft tissue masses with myxoid stroma: Can conventional magnetic resonance imaging differentiate benign from malignant tumors?

Energy Technology Data Exchange (ETDEWEB)

Crombe, A., E-mail: amandine.crombe@ens-lyon.fr [Department of Radiology, Institut Bergonié, 229 cours de l’Argonne, 33076 Bordeaux Cedex (France); Alberti, N. [Department of Radiology, Institut Bergonié, 229 cours de l’Argonne, 33076 Bordeaux Cedex (France); Stoeckle, E. [Department of Surgery, Institut Bergonié, 229 cours de l’Argonne, 33076 Bordeaux Cedex (France); Brouste, V. [Clinical and Epidemiological Research Unit, Institut Bergonié, 33000 Bordeaux (France); Buy, X. [Department of Radiology, Institut Bergonié, 229 cours de l’Argonne, 33076 Bordeaux Cedex (France); Coindre, J-M. [Department of Pathology, Institut Bergonié, 229 cours de l’Argonne, 33076 Bordeaux Cedex (France); Kind, M. [Department of Radiology, Institut Bergonié, 229 cours de l’Argonne, 33076 Bordeaux Cedex (France)

2016-10-15

Objectives: To retrospectively evaluate the diagnostic performance of morphological signs observed on conventional magnetic resonance (MR) imaging to differentiate benign from malignant peripheral solid tumors of soft tissue with myxoid stroma. Methods: MR images from 95 consecutive histopathologically proven tumors (26 benign and 69 malignant) of soft tissues with myxoid components were evaluated in our tertiary referral center. Two radiologists, blind to pathology results, independently reviewed conventional MR sequences including at least a) one T2-weighted sequence with or without fat suppression; b) one T1-weighted sequence without fat suppression; and c) one T1-weighted sequence with gadolinium-complex contrast enhancement and fat suppression. Multiple criteria were defined to analyze morphology, margins, architecture and tumor periphery and evaluated for each lesion. Intra- and inter-observer reproducibility and Odds ratios were calculated for each criterion. Results: The most relevant and reproducible criteria to significantly predict malignancy were: (1) ill-defined tumor margins, (2) a hemorrhagic component, (3) intra-tumoral fat, (4) fibrosis and (5) the “tail sign”. A lesion is classified as malignant if any of these 5 criteria is present, and benign if none of them are observed. Therefore, this combination provides a sensitivity of 92.9% and a specificity of 93.3%. Conclusion: Conventional MR imaging provides reproducible criteria that can be combined to differentiate between benign and malignant solid tumors of soft tissue with myxoid stroma.

Factors associated with tumor size of hepatocellular carcinoma

Science.gov (United States)

Siregar, G. A.; Buulolo, B. A.

2018-03-01

Determining the association of age and laboratory parameters with tumor size of hepatocellular carcinoma (HCC). The study was at Adam Malik Hospital Medan from June- December 2016. 100 HCC patients were enrolled; those with excluding liver metastatic. Baseline characteristics of gender, age, obtaining etiology of HCC. Liver function tests, viral marker, and INR were done. Based on tumor size from abdomen CT, patients were three groups: tumor size below 3 cm, 3-5 cm, and above 5 cm size. Patients were also divided based on Child-Pugh class. Correlation of age and laboratory results with tumor size of HCC patients were analyzed. Age have negative correlation with tumor size in HCC patients (r=-0.297, p=0.032) while AFP have positive correlation with tumor size (r0.446, p=<0.001). Total bilirubin, AST, and ALT have negative correlation but non-significant (r=-0.045, -0.078, - 0.126 respectively). Albumin and INR have positive correlation but non-significant (r=0.021, 0.112 respectively). Our study suggests that older age correlates with smaller tumor size, while AFP level has a significant correlation with tumor size in HCC patients. AFP level may be a useful marker for determining the prognosis of HCC patients.

Optimization of dendritic cell loading with tumor cell lysates for cancer immunotherapy.

Science.gov (United States)

Hatfield, Paul; Merrick, Alison E; West, Emma; O'Donnell, Dearbhaile; Selby, Peter; Vile, Richard; Melcher, Alan A

2008-09-01

The immune response to cancer is critically determined by the way in which tumor cells die. As necrotic, stress-associated death can be associated with activation of antitumor immunity, whole tumor cell antigen loading strategies for dendritic cell (DC)-based vaccination have commonly used freeze-thaw "necrotic" lysates as an immunogenic source of tumor-associated antigens. In this study, the effect of such lysates on the ability of DCs to mature in response to well-established maturation stimuli was examined, and methods to enhance lysate-induced DC activation explored. Freeze-thaw lysates were prepared from murine tumor cell lines and their effects on bone marrow-derived DC maturation and function examined. Unmodified freeze-thaw tumor cell lysates inhibited the toll-like receptor-induced maturation and function of bone marrow-derived DCs, preventing up-regulation of CD40, CD86, and major histocompatibility complex class II, and reducing secretion of inflammatory cytokines [interleukin (IL)-12 p70, tumor necrosis factor-alpha, and IL-6]. Although IL-10 secretion was increased by lysate-pulsed DCs, this was not responsible for the observed suppression of IL-12. Although activation of the nuclear factor-kappaB pathway remained intact, the kinase activity of phosphorylated p38 mitogen-activated protein kinase was inhibited in lysate-pulsed DCs. Lysate-induced DC suppression was partially reversed in vitro by induction of tumor cell stress before lysis, and only DCs loaded with stressed lysates afforded protection against tumor challenge in vivo. These data suggest that ex vivo freeze-thaw of tumor cells does not effectively mimic in vivo immunogenic necrosis, and advocates careful characterization and optimization of tumor cell-derived vaccine sources for cancer immunotherapy.

The influence of age at time of exposure to 239Pu or 226Ra on retention, distribution, survival and tumor induction in Beagles

International Nuclear Information System (INIS)

Bruenger, F.W.; Miller, S.C.; Lloyd, R.D.

1991-01-01

The influence of age at injection of 226 Ra or 239 Pu on skeletal deposition and local distribution, the pattern of bone tumor formation and post-injection survival were studied in parallel short-term mechanistic and lifetime toxicity experiments. Beagles received a single intravenous injection of 226 Ra or 239 Pu at age 3 months (juveniles), 17-19 months (young adults) or 60 months (mature). Data from short-term mechanistic-dosimetric studies and from one dosage level (41 kBq 226 Ra/kg or 11 kBq 239 Pu/kg body mass) of each of the toxicity experiments were compared. Skeletal growth and turnover produced differential initial deposition and distribution patterns typical for each age group. The highest bone tumor incidence was seen in the young adult groups. Differences were observed in bone tumor location between dogs in the same age group given radium or plutonium and among age groups injected with either radionuclide, and some of these could be explained by differences in local dose distributions (e.g., trabecular vs. cortical bone). Cox regression indicated no significant differences in post-injection survivals (uncorrected for the different pre-injection periods) of Ra-injected groups, but there was a statistically significant difference among the Pu-injected groups. Neutron-induced autoradiography showed that differences in the effects of Pu in the three age groups were due primarily to the age- and time-dependent local distribution of the nuclide

Tumor necrosis factor-alpha inhibits differentiation of myogenic cells in human urethral rhabdosphincter.

Science.gov (United States)

Shinohara, Mayuka; Sumino, Yasuhiro; Sato, Fuminori; Kiyono, Tohru; Hashimoto, Naohiro; Mimata, Hiromitsu

2017-06-01

To examine the inhibitory effects of tumor necrosis factor-α on myogenic differentiation of human urethral rhabdosphincter cells. A rhabdosphincter sample was obtained from a patient who underwent total cystectomy. To expand the lifespan of the primary cultured cells, rhabdosphincter myogenic cells were immortalized with mutated cyclin-dependent kinase 4, cyclin D1 and telomerase. The differential potential of the cells was investigated. The transfected human rhabdosphincter cells were induced for myogenic differentiation with recombinant human tumor necrosis factor-α and/or the tumor necrosis factor-α antagonist etanercept at different concentrations, and activation of signaling pathways was monitored. Human rhabdosphincter cells were selectively cultured for at least 40 passages. Molecular analysis confirmed the expression of myosin heavy chain, which is a specific marker of differentiated muscle cells, significantly increased after differentiation induction. Although tumor necrosis factor-α treatment reduced the myosin heavy chain expression in a concentration-dependent manner, etanercept inhibited this suppression. Tumor necrosis factor-α suppressed phosphorylation of protein kinase B and p38, whereas etanercept pretreatment promoted phosphorylation and myosin heavy chain expression in a concentration-dependent manner. Tumor necrosis factor-α inhibits differentiation of urethral rhabdosphincter cells in part through the p38 mitogen-activated protein kinase and phosphoinositide 3-kinase pathways. Inhibition of tumor necrosis factor-α might be a useful strategy to treat stress urinary incontinence. © 2017 The Japanese Urological Association.

p16(INK4a translation suppressed by miR-24.

Directory of Open Access Journals (Sweden)

Ashish Lal

2008-03-01

Full Text Available Expression of the tumor suppressor p16(INK4a increases during aging and replicative senescence.Here, we report that the microRNA miR-24 suppresses p16 expression in human diploid fibroblasts and cervical carcinoma cells. Increased p16 expression with replicative senescence was associated with decreased levels of miR-24, a microRNA that was predicted to associate with the p16 mRNA coding and 3'-untranslated regions. Ectopic miR-24 overexpression reduced p16 protein but not p16 mRNA levels. Conversely, introduction of antisense (AS-miR-24 blocked miR-24 expression and markedly enhanced p16 protein levels, p16 translation, and the production of EGFP-p16 reporter bearing the miR-24 target recognition sites.Together, our results suggest that miR-24 represses the initiation and elongation phases of p16 translation.

Radiation therapy for malignant tumors in patients 80 years of age or older

International Nuclear Information System (INIS)

Mitsuhashi, Norio; Niibe, Hideo; Hayakawa, Kazushige; Takahashi, Mitsuhiro; Nozaki, Miwako; Yamakawa, Michitaka

1992-01-01

We report here, results of investigation of changes in the condition of elderly patients, 80 years of age or older (EP-80), treated with radiation, and analysis of the results of radiotherapy to assess the value of radiotherapy in treating the elderly. Between 1970 and 1989, 294 EP-80 with various malignant tumors received radiation therapy at the Department of Radiology, Gunma University Hospital. The number of EP-80 treated has increased recently to about thirty per year, and their incidence among newly registered patients has also increased to over 5%. The 5-year cause specific survival rates for male and female were 14% and 32%, respectively. There was a significant difference between the survival rates for male and female (x 2 =11.89, p=0.00056) because of inclusion of a significant proportion of female patients with gynecological malignancies. The 5-year survival rate for patients in the curative radiotherapy group (CRG) was 30%, whereas no patient of the palliative radiotherapy group (PRG) has survived for 5 years (x 2 =90.23, p=0.00000). In the CRG, the survival rate for females was significantly higher than that for males (x 2 =11.48, p=0.00070). Thirty-one patients survived for 5 year. Head and neck cancer and uterine lervix cancer were the most common tumors in 5 year survivors. Age was not a significant prognostic factor in the elderly patients treated with radiation. It is considered that radiation therapy is as valuable in elderly patients as in the younger patient population. (author)

The Novel miR-9600 Suppresses Tumor Progression and Promotes Paclitaxel Sensitivity in Non–small-cell Lung Cancer Through Altering STAT3 Expression

Directory of Open Access Journals (Sweden)

Cheng-Cao Sun

2016-01-01

Full Text Available MicroRNAs have been identified to be involved in center stage of cancer biology. They accommodate cell proliferation and migration by negatively regulate gene expression either by hampering the translation of targeted mRNAs or by promoting their degradation. We characterized and identified the novel miR-9600 and its target in human non–small-cell lung cancer (NSCLC. Our results demonstrated that the miR-9600 were downregulated in NSCLC tissues and cells. It is confirmed that signal transducer and activator of transcription 3 (STAT3, a putative target gene, is directly inhibited by miR-9600. The miR-9600 markedly suppressed the protein expression of STAT3, but with no significant influence in corresponding mRNA levels, and the direct combination of miR-9600 and STAT3 was confirmed by a luciferase reporter assay. miR-9600 inhibited cell growth, hampered expression of cell cycle-related proteins and inhibited cell migration and invasion in human NSCLC cell lines. Further, miR-9600 significantly suppressed tumor growth in nude mice. Similarly, miR-9600 impeded tumorigenesis and metastasis through directly targeting STAT3. Furthermore, we identified that miR-9600 augmented paclitaxel and cisplatin sensitivity by downregulating STAT3 and promoting chemotherapy-induced apoptosis. These data demonstrate that miR-9600 might be a useful and novel therapeutic target for NSCLC.

Markers of epithelial-to-mesenchymal transition reflect tumor biology according to patient age and Gleason score in prostate cancer.

Directory of Open Access Journals (Sweden)

Dorota Jędroszka

Full Text Available Prostate carcinoma (PRAD is one of the most frequently diagnosed malignancies amongst men worldwide. It is well-known that androgen receptor (AR plays a pivotal role in a vast majority of prostate tumors. However, recent evidence emerged stating that estrogen receptors (ERs may also contribute to prostate tumor development. Moreover, progression and aggressiveness of prostate cancer may be associated with differential expression genes of epithelial-to-mesenchymal transition (EMT. Therefore we aimed to assess the significance of receptors status as well as EMT marker genes expression among PRAD patients in accordance to their age and Gleason score.We analyzed TCGA gene expression profiles of 497 prostate tumor samples according to 43 genes involved in EMT and 3 hormone receptor genes (AR, ESR1, ESR2 as well as clinical characteristic of cancer patients. Then patients were divided into four groups according to their age and 5 groups according to Gleason score. Next, we evaluated PRAD samples according to relationship between the set of variables in different combinations and compared differential expression in subsequent groups of patients. The analysis was applied using R packages: FactoMineR, gplots, RColorBrewer and NMF.MFA analysis resulted in distinct grouping of PRAD patients into four age categories according to expression level of AR, ESR1 and ESR2 with the most distinct group of age less than 50 years old. Further investigations indicated opposite expression profiles of EMT markers between different age groups as well as strong association of EMT gene expression with Gleason score. We found that depending on age of prostate cancer patients and Gleason score EMT genes with distinctly altered expression are: KRT18, KRT19, MUC1 and COL4A1, CTNNB1, SNAI2, ZEB1 and MMP3.Our major observation is that prostate cancer from patients under 50 years old compared to older ones has entirely different EMT gene expression profiles showing potentially

U1 Adaptor Oligonucleotides Targeting BCL2 and GRM1 Suppress Growth of Human Melanoma Xenografts In Vivo

Directory of Open Access Journals (Sweden)

Rafal Goraczniak

2013-01-01

Full Text Available U1 Adaptor is a recently discovered oligonucleotide-based gene-silencing technology with a unique mechanism of action that targets nuclear pre-mRNA processing. U1 Adaptors have two distinct functional domains, both of which must be present on the same oligonucleotide to exert their gene-silencing function. Here, we present the first in vivo use of U1 Adaptors by targeting two different human genes implicated in melanomagenesis, B-cell lymphoma 2 (BCL2 and metabotropic glutamate receptor 1 (GRM1, in a human melanoma cell xenograft mouse model system. Using a newly developed dendrimer delivery system, anti-BCL2 U1 Adaptors were very potent and suppressed tumor growth at doses as low as 34 µg/kg with twice weekly intravenous (iv administration. Anti-GRM1 U1 Adaptors suppressed tumor xenograft growth with similar potency. Mechanism of action was demonstrated by showing target gene suppression in tumors and by observing that negative control U1 Adaptors with just one functional domain show no tumor suppression activity. The anti-BCL2 and anti-GRM1 treatments were equally effective against cell lines harboring either wild-type or a mutant V600E B-RAF allele, the most common mutation in melanoma. Treatment of normal immune-competent mice (C57BL6 indicated no organ toxicity or immune stimulation. These proof-of-concept studies represent an in-depth (over 800 mice in ~108 treatment groups validation that U1 Adaptors are a highly potent gene-silencing therapeutic and open the way for their further development to treat other human diseases.

Sox4 Links Tumor Suppression to Accelerated Aging in Mice by Modulating Stem Cell Activation

Directory of Open Access Journals (Sweden)

Miguel Foronda

2014-07-01

Full Text Available Sox4 expression is restricted in mammals to embryonic structures and some adult tissues, such as lymphoid organs, pancreas, intestine, and skin. During embryogenesis, Sox4 regulates mesenchymal and neural progenitor survival, as well as lymphocyte and myeloid differentiation, and contributes to pancreas, bone, and heart development. Aberrant Sox4 expression is linked to malignant transformation and metastasis in several types of cancer. To understand the role of Sox4 in the adult organism, we first generated mice with reduced whole-body Sox4 expression. These mice display accelerated aging and reduced cancer incidence. To specifically address a role for Sox4 in adult stem cells, we conditionally deleted Sox4 (Sox4cKO in stratified epithelia. Sox4cKO mice show increased skin stem cell quiescence and resistance to chemical carcinogenesis concomitantly with downregulation of cell cycle, DNA repair, and activated hair follicle stem cell pathways. Altogether, these findings highlight the importance of Sox4 in regulating adult tissue homeostasis and cancer.

Risk of borderline ovarian tumors among women with benign ovarian tumors

DEFF Research Database (Denmark)

Guleria, Sonia; Jensen, Allan; Kjær, Susanne K

2018-01-01

tumors among women with a benign ovarian tumor. METHODS: This nationwide cohort study included all Danish women diagnosed with a benign ovarian tumor (n=139,466) during 1978-2012. The cohort was linked to the Danish Pathology Data Bank and standardized incidence ratios (SIR) with 95% confidence intervals...... (CI) were calculated. RESULTS: Women with benign ovarian tumors had increased risks for subsequent borderline ovarian tumors (SIR 1.62, 95% CI 1.43-1.82), and this applied to both serous (SIR 1.69, 95% CI 1.39-2.03) and mucinous (SIR 1.75, 95% CI 1.45-2.10) histotypes of borderline ovarian tumors....... The risk for borderline ovarian tumors was primarily increased for women diagnosed with a benign ovarian tumor before 40years of age. The risk remained increased up to 9years after a benign ovarian tumor diagnosis. Finally, the associations did not change markedly when analyzed for the different histotypes...

Application of 10BSH entrapped transferrin-PEG-liposome to boron neutron-capture therapy (BNCT) for solid tumor

International Nuclear Information System (INIS)

Maruyama, K.; Ishida, O.; Iwatsuru, M.; Yanagie, H.; Eriguchi, M.; Kobayashi, H.

2000-01-01

The successful treatment of cancer by BNCT requires the selective concentration of 10 B within malignant tumor cells. Intracellular targeting ability and cytotoxic effects of 10 B entrapped TF-PEG-liposomes, in which TF is covalently linked to the distal terminal of PEG chains on the external surface of PEG-liposomes, were examined in Colon 26 tumor-bearing mice. TF-PEG-liposomes readily bound to tumor cells in vivo, and were internalized by receptor-mediated endocytosis. 10 B-PEG-liposomes and 10 B-TF-PEG-liposomes showed prolonged residence time in the circulation and low RES uptake in tumor-bearing mice, resulting in enhanced extravasation of the liposomes into the solid tumor tissue and reached high level of 10 B content in tumor. After thermal neutron irradiation of mice injected with 10 B-PEG-liposomes or 10 B-TF-PEG-liposome, tumor growth was suppressed relative to controls. These results suggest that intravenous injection of 10 B TF-PEG-liposome can increase the intracellular retention of 10 B atoms, which were introduced by receptor mediated endocytosis after binding, causing tumor growth suppression in vivo upon thermal neutron irradiation. (author)

Metoclopramide unmasks potentially misleading contralateral suppression in patients undergoing adrenal vein sampling for primary aldosteronism.

Science.gov (United States)

Rossitto, Giacomo; Miotto, Diego; Battistel, Michele; Barbiero, Giulio; Maiolino, Giuseppe; Bisogni, Valeria; Sanga, Viola; Rossi, Gian Paolo

2016-11-01

As metoclopramide stimulates aldosterone secretion, we tested its usefulness in the assessment of lateralization of primary aldosteronism by adrenal vein sampling (AVS). Prospective within-patient study in consecutive patients undergoing AVS for primary aldosteronism subtyping. We compared the diagnostic accuracy of baseline and postmetoclopramide lateralization index and relative (to cortisol) aldosterone secretion indices (RASI) for each adrenal gland with aldosterone-producing adenoma (APA) determined by the four corners criteria as the reference diagnosis. We recruited 93 consecutive patients (mean age: 52 years; women 31%). Metoclopramide increased plasma aldosterone in the inferior vena cava and in both adrenal veins. The postmetoclopramide lateralization index was accurate in identifying APA, but did not increase diagnostic accuracy over baseline lateralization index, because the RASI increased similarly in both sides. Conversely, metoclopramide raised RASI to values more than 0.90 bilaterally in non-APA patients allowing accurate identification of factitious aldosterone suppression. In contrast, RASI was 0.90 or less in 48% contralateral to the tumor in APA patients. Regression analysis showed the APA patients with persistent suppression of RASI contralaterally showed a more florid primary aldosteronism phenotype. Metoclopramide does not enhance lateralization of aldosterone excess in APA, but consistently increased the value of RASI in non-APA cases, thus unmasking potentially misleading suppression of aldosterone. Postmetoclopramide RASI may therefore allow a more precise diagnosis when AVS can be achieved only unilaterally.

TNF Counterbalances the Emergence of M2 Tumor Macrophages

Directory of Open Access Journals (Sweden)

Franz Kratochvill

2015-09-01

Full Text Available Cancer can involve non-resolving, persistent inflammation where varying numbers of tumor-associated macrophages (TAMs infiltrate and adopt different activation states between anti-tumor M1 and pro-tumor M2 phenotypes. Here, we resolve a cascade causing differential macrophage phenotypes in the tumor microenvironment. Reduction in TNF mRNA production or loss of type I TNF receptor signaling resulted in a striking pattern of enhanced M2 mRNA expression. M2 gene expression was driven in part by IL-13 from eosinophils co-recruited with inflammatory monocytes, a pathway that was suppressed by TNF. Our data define regulatory nodes within the tumor microenvironment that balance M1 and M2 populations. Our results show macrophage polarization in cancer is dynamic and dependent on the balance between TNF and IL-13, thus providing a strategy for manipulating TAMs.

Monoclonal TCR-redirected tumor cell killing.

Science.gov (United States)

Liddy, Nathaniel; Bossi, Giovanna; Adams, Katherine J; Lissina, Anna; Mahon, Tara M; Hassan, Namir J; Gavarret, Jessie; Bianchi, Frayne C; Pumphrey, Nicholas J; Ladell, Kristin; Gostick, Emma; Sewell, Andrew K; Lissin, Nikolai M; Harwood, Naomi E; Molloy, Peter E; Li, Yi; Cameron, Brian J; Sami, Malkit; Baston, Emma E; Todorov, Penio T; Paston, Samantha J; Dennis, Rebecca E; Harper, Jane V; Dunn, Steve M; Ashfield, Rebecca; Johnson, Andy; McGrath, Yvonne; Plesa, Gabriela; June, Carl H; Kalos, Michael; Price, David A; Vuidepot, Annelise; Williams, Daniel D; Sutton, Deborah H; Jakobsen, Bent K

2012-06-01

T cell immunity can potentially eradicate malignant cells and lead to clinical remission in a minority of patients with cancer. In the majority of these individuals, however, there is a failure of the specific T cell receptor (TCR)–mediated immune recognition and activation process. Here we describe the engineering and characterization of new reagents termed immune-mobilizing monoclonal TCRs against cancer (ImmTACs). Four such ImmTACs, each comprising a distinct tumor-associated epitope-specific monoclonal TCR with picomolar affinity fused to a humanized cluster of differentiation 3 (CD3)-specific single-chain antibody fragment (scFv), effectively redirected T cells to kill cancer cells expressing extremely low surface epitope densities. Furthermore, these reagents potently suppressed tumor growth in vivo. Thus, ImmTACs overcome immune tolerance to cancer and represent a new approach to tumor immunotherapy.

Lysyl Oxidase and the Tumor Microenvironment

Directory of Open Access Journals (Sweden)

Tong-Hong Wang

2016-12-01

Full Text Available The lysyl oxidase (LOX family of oxidases contains a group of extracellular copper-dependent enzymes that catalyze the cross-linking of collagen and elastin by oxidation, thus maintaining the rigidity and structural stability of the extracellular matrix (ECM. Aberrant expression or activation of LOX alters the cellular microenvironment, leading to many diseases, including atherosclerosis, tissue fibrosis, and cancer. Recently, a number of studies have shown that LOX is overexpressed in most cancers and that it is involved in the regulation of tumor progression and metastasis. In contrast, a few reports have also indicated the tumor-suppressing role of LOX. In this short review, we discuss recent research on the correlations between LOX and cancer. Further, the role of LOX in tumor microenvironment remodeling, tumorigenesis, and metastasis and the underlying mechanisms have also been elucidated.

Maximizing Tumor Immunity With Fractionated Radiation

Energy Technology Data Exchange (ETDEWEB)

Schaue, Doerthe, E-mail: dschaue@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ratikan, Josephine A.; Iwamoto, Keisuke S.; McBride, William H. [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States)

2012-07-15

Purpose: Technologic advances have led to increased clinical use of higher-sized fractions of radiation dose and higher total doses. How these modify the pathways involved in tumor cell death, normal tissue response, and signaling to the immune system has been inadequately explored. Here we ask how radiation dose and fraction size affect antitumor immunity, the suppression thereof, and how this might relate to tumor control. Methods and Materials: Mice bearing B16-OVA murine melanoma were treated with up to 15 Gy radiation given in various-size fractions, and tumor growth followed. The tumor-specific immune response in the spleen was assessed by interferon-{gamma} enzyme-linked immunospot (ELISPOT) assay with ovalbumin (OVA) as the surrogate tumor antigen and the contribution of regulatory T cells (Tregs) determined by the proportion of CD4{sup +}CD25{sup hi}Foxp3{sup +} T cells. Results: After single doses, tumor control increased with the size of radiation dose, as did the number of tumor-reactive T cells. This was offset at the highest dose by an increase in Treg representation. Fractionated treatment with medium-size radiation doses of 7.5 Gy/fraction gave the best tumor control and tumor immunity while maintaining low Treg numbers. Conclusions: Radiation can be an immune adjuvant, but the response varies with the size of dose per fraction. The ultimate challenge is to optimally integrate cancer immunotherapy into radiation therapy.

Phenotypic and Functional Properties of Tumor-Infiltrating Regulatory T Cells

Directory of Open Access Journals (Sweden)

Gap Ryol Lee

2017-01-01

Full Text Available Regulatory T (Treg cells maintain immune homeostasis by suppressing excessive immune responses. Treg cells induce tolerance against self- and foreign antigens, thus preventing autoimmunity, allergy, graft rejection, and fetus rejection during pregnancy. However, Treg cells also infiltrate into tumors and inhibit antitumor immune responses, thus inhibiting anticancer therapy. Depleting whole Treg cell populations in the body to enhance anticancer treatments will produce deleterious autoimmune diseases. Therefore, understanding the precise nature of tumor-infiltrating Treg cells is essential for effectively targeting Treg cells in tumors. This review summarizes recent results relating to Treg cells in the tumor microenvironment, with particular emphasis on their accumulation, phenotypic, and functional properties, and targeting to enhance the efficacy of anticancer treatment.

Norcantharidin inhibits tumor growth and vasculogenic mimicry of human gallbladder carcinomas by suppression of the PI3-K/MMPs/Ln-5γ2 signaling pathway

International Nuclear Information System (INIS)

Zhang, Jing-Tao; Sun, Wei; Zhang, Wen-Zhong; Ge, Chun-Yan; Liu, Zhong-Yan; Zhao, Ze-Ming; Lu, Xing-Sui; Fan, Yue-Zu

2014-01-01

< 0.01, vs. control group); NCTD down-regulated expression of these VM signaling-related markers in vitro and in vivo. NCTD inhibited tumor growth and VM of human GBCs in vitro and in vivo by suppression of the PI3-K/MMPs/Ln-5γ2 signaling pathway. It is firstly concluded that NCTD may be a potential anti-VM agent for human GBCs

Abundant immunohistochemical expression of dopamine D2 receptor and p53 protein in meningiomas: follow-up, relation to gender, age, tumor grade, and recurrence

International Nuclear Information System (INIS)

Trott, G.; Pereira-Lima, J.F.S.; Leães, C.G.S.; Ferreira, N.P.; Barbosa-Coutinho, L.M.; Oliveira, M.C.

2015-01-01

Meningiomas are common, usually benign tumors, with a high postoperative recurrence rate. However, the genesis and development of these tumors remain controversial. We aimed to investigate the presence and implications of a mutated p53 protein and dopamine D 2 receptor in a representative series of meningiomas and to correlate these findings with age, gender, tumor grade, and recurrence. Tumor tissue samples of 157 patients diagnosed with meningioma (37 males and 120 females, mean age 53.6±14.3 years) who underwent surgical resection between 2003 and 2012 at our institution were immunohistochemically evaluated for the presence of p53 protein and dopamine D 2 receptor and were followed-up to analyze tumor recurrence or regrowth. Tumors were classified as grades I (n=141, 89.8%), II (n=13, 8.3%), or grade III (n=3, 1.9%). Dopamine D 2 receptor and p53 protein expression were positive in 93.6% and 49.7% of the cases, respectively. Neither of the markers showed significant expression differences among different tumor grades or recurrence or regrowth statuses. Our findings highlight the potential role of p53 protein in meningioma development and/or progression. The high positivity of dopamine D 2 receptor observed in this study warrants further investigation of the therapeutic potential of dopamine agonists in the evolution of meningiomas

Mandatory chromosomal segment balance in aneuploid tumor cells

International Nuclear Information System (INIS)

Kost-Alimova, Maria; Stanbridge, Eric; Klein, George; Imreh, Stefan; Darai-Ramqvist, Eva; Yau, Wing Lung; Sandlund, Agneta; Fedorova, Ludmila; Yang, Ying; Kholodnyuk, Irina; Cheng, Yue; Li Lung, Maria

2007-01-01

Euploid chromosome balance is vitally important for normal development, but is profoundly changed in many tumors. Is each tumor dependent on its own structurally and numerically changed chromosome complement that has evolved during its development and progression? We have previously shown that normal chromosome 3 transfer into the KH39 renal cell carcinoma line and into the Hone1 nasopharyngeal carcinoma line inhibited their tumorigenicity. The aim of the present study was to distinguish between a qualitative and a quantitative model of this suppression. According to the former, a damaged or deleted tumor suppressor gene would be restored by the transfer of a normal chromosome. If so, suppression would be released only when the corresponding sequences of the exogenous normal chromosome are lost or inactivated. According to the alternative quantitative model, the tumor cell would not tolerate an increased dosage of the relevant gene or segment. If so, either a normal cell derived, or, a tumor derived endogenous segment could be lost. Fluorescence in Situ Hybridization based methods, as well as analysis of polymorphic microsatellite markers were used to follow chromosome 3 constitution changes in monochromosomal hybrids. In both tumor lines with introduced supernumerary chromosomes 3, the copy number of 3p21 or the entire 3p tended to fall back to the original level during both in vitro and in vivo growth. An exogenous, normal cell derived, or an endogenous, tumor derived, chromosome segment was lost with similar probability. Identification of the lost versus retained segments showed that the intolerance for increased copy number was particularly strong for 3p14-p21, and weaker for other 3p regions. Gains in copy number were, on the other hand, well tolerated in the long arm and particularly the 3q26-q27 region. The inability of the cell to tolerate an experimentally imposed gain in 3p14-p21 in contrast to the well tolerated gain in 3q26-q27 is consistent with the

Canolol inhibits gastric tumors initiation and progression through COX-2/PGE2 pathway in K19-C2mE transgenic mice.

Directory of Open Access Journals (Sweden)

Donghui Cao

Full Text Available 4-Vinyl-2, 6-dimethoxyphenol (canolol is an antioxidant phenolic compound extracted from crude canola oil. In current research, K19-C2mE transgenic mice, developing hyperplastic tumors spontaneously in the glandular stomach, were used to study the mechanisms involved in the anti-inflammation and anti-tumor effects of canolol. Tg mice receiving canolol diet had a reduced tumor incidence, to 41.2%, compared with Non-treatment Tg mice, 77.8% of which had gastric tumor (P=0.002. Besides that, the mean tumor diameter was decreased from 6.5 mm to 4.5 mm (P<0.001 after canolol administration. COX-2/PGE2 pathway is known to play pivotal role in inflammation-induced gastric tumorigenesis. The neutrophils and lymphocytes infiltration was suppressed significantly, and the mRNA levels of the proinflammatory cytokines COX-2, IL-1β and IL-12b were also downregulated in gastric mucosa. Additionally, immunohistochemical analysis showed that COX-2, EP2, Gαs and β-catenin, key factors involving in PGE2 signal transduction, were positive staining with higher H scores in Non-treatment Tg mice, while the expressions were suppressed significantly by 0.1% canolol (P<0.001. In addition, tumor-suppressor miR-7 was reactivated after canolol administration, and COX-2 was showed to be a functional target of miR-7 to suppress the tumor progression. In conclusion, canolol could inhibit the gastritis-related tumor initiation and progression, and the suppression effect was correlated with the blocking up of canonical COX-2/PGE2 signaling pathway and might be regulated by miR-7.

COX-2 and Prostaglandin EP3/EP4 Signaling Regulate the Tumor Stromal Proangiogenic Microenvironment via CXCL12-CXCR4 Chemokine Systems

Science.gov (United States)

Katoh, Hiroshi; Hosono, Kanako; Ito, Yoshiya; Suzuki, Tatsunori; Ogawa, Yasufumi; Kubo, Hidefumi; Kamata, Hiroki; Mishima, Toshiaki; Tamaki, Hideaki; Sakagami, Hiroyuki; Sugimoto, Yukihiko; Narumiya, Shuh; Watanabe, Masahiko; Majima, Masataka

2010-01-01

Bone marrow (BM)–derived hematopoietic cells, which are major components of tumor stroma, determine the tumor microenvironment and regulate tumor phenotypes. Cyclooxygenase (COX)−2 and endogenous prostaglandins are important determinants for tumor growth and tumor-associated angiogenesis; however, their contributions to stromal formation and angiogenesis remain unclear. In this study, we observed that Lewis lung carcinoma cells implanted in wild-type mice formed a tumor mass with extensive stromal formation that was markedly suppressed by COX-2 inhibition, which reduced the recruitment of BM cells. Notably, COX-2 inhibition attenuated CXCL12/CXCR4 expression as well as expression of several other chemokines. Indeed, in a Matrigel model, prostaglandin (PG) E2 enhanced stromal formation and CXCL12/CXCR4 expression. In addition, a COX-2 inhibitor suppressed stromal formation and reduced expression of CXCL12/CXCR4 and a fibroblast marker (S100A4) in a micropore chamber model. Moreover, stromal formation after tumor implantation was suppressed in EP3−/− mice and EP4−/− mice, in which stromal expression of CXCL12/CXCR4 and S100A4 was reduced. The EP3 or EP4 knockout suppressed S100A4+ fibroblasts, CXCL12+, and/or CXCR4+ stromal cells as well. Immunofluorescent analyses revealed that CXCL12+CXCR4+S100A4+ fibroblasts mainly comprised stromal cells and most of these were recruited from the BM. Additionally, either EP3- or EP4-specific agonists stimulated CXCL12 expression by fibroblasts in vitro. The present results address the novel activities of COX-2/PGE2-EP3/EP4 signaling that modulate tumor biology and show that CXCL12/CXCR4 axis may play a crucial role in tumor stromal formation and angiogenesis under the control of prostaglandins. PMID:20110411

Imaging findings of sacral tumors

International Nuclear Information System (INIS)

Kim, Seung Ho; Hong, Sung Hwan; Choi, Ja Young; Koh, Sung Hye; Chung, Hye Won; Choi, Jung Ah; Kang, Heung Sik

2003-01-01

The various pathologic conditions detected at CT and MRI and subsumed by the term 'sacral tumor' include primary bone tumors, sacral canal tumors and metastases. Among these, metastases are much more common than primary bone tumors, of which chordoma is the most common. Although the imaging findings of sacral tumors are nonspecific, a patient's age and sex, and specific findings such as calcification or fluid-fluid levels, can help radiologists in their differential diagnosis. We describe the imaging findings of primary sacral tumors, emphasizing the MRI findings

Suppression of Antitumor Immune Responses by Human Papillomavirus through Epigenetic Downregulation of CXCL14

Directory of Open Access Journals (Sweden)

Louis Cicchini

2016-05-01

Full Text Available High-risk human papillomaviruses (HPVs are causally associated with multiple human cancers. Previous studies have shown that the HPV oncoprotein E7 induces immune suppression; however, the underlying mechanisms remain unknown. To understand the mechanisms by which HPV deregulates host immune responses in the tumor microenvironment, we analyzed gene expression changes of all known chemokines and their receptors using our global gene expression data sets from human HPV-positive and -negative head/neck cancer and cervical tissue specimens in different disease stages. We report that, while many proinflammatory chemokines increase expression throughout cancer progression, CXCL14 is dramatically downregulated in HPV-positive cancers. HPV suppression of CXCL14 is dependent on E7 and associated with DNA hypermethylation in the CXCL14 promoter. Using in vivo mouse models, we revealed that restoration of Cxcl14 expression in HPV-positive mouse oropharyngeal carcinoma cells clears tumors in immunocompetent syngeneic mice, but not in Rag1-deficient mice. Further, Cxcl14 reexpression significantly increases natural killer (NK, CD4+ T, and CD8+ T cell infiltration into the tumor-draining lymph nodes in vivo. In vitro transwell migration assays show that Cxcl14 reexpression induces chemotaxis of NK, CD4+ T, and CD8+ T cells. These results suggest that CXCL14 downregulation by HPV plays an important role in suppression of antitumor immune responses. Our findings provide a new mechanistic understanding of virus-induced immune evasion that contributes to cancer progression.

Cyclophilin A enhances cell proliferation and tumor growth of liver fluke-associated cholangiocarcinoma

Directory of Open Access Journals (Sweden)

Sawanyawisuth Kanlayanee

2011-08-01

Full Text Available Abstract Background Cyclophilin A (CypA expression is associated with malignant phenotypes in many cancers. However, the role and mechanisms of CypA in liver fluke-associated cholangiocarcinoma (CCA are not presently known. In this study, we investigated the expression of CypA in CCA tumor tissues and CCA cell lines as well as regulation mechanisms of CypA in tumor growth using CCA cell lines. Methods CypA expression was determined by real time RT-PCR, Western blot or immunohistochemistry. CypA silence or overexpression in CCA cells was achieved using gene delivery techniques. Cell proliferation was assessed using MTS assay or Ki-67 staining. The effect of silencing CypA on CCA tumor growth was determined in nude mice. The effect of CypA knockdown on ERK1/2 activation was assessed by Western blot. Results CypA was upregulated in 68% of CCA tumor tissues. Silencing CypA significantly suppressed cell proliferation in several CCA cell lines. Likewise, inhibition of CypA peptidyl-prolyl cis-trans isomerase (PPIase activity using cyclosporin A (CsA decreased cell proliferation. In contrast, overexpression of CypA resulted in 30% to 35% increases in proliferation of CCA cell lines. Interestingly, neither silence nor overexpression of CypA affected cell proliferation of a non-tumor human cholangiocyte cell line, MMNK1. Suppression of CypA expression attenuated ERK1/2 activity in CCA M139 cells by using both transient and stable knockdown methods. In the in vivo study, there was a 43% reduction in weight of tumors derived from CypA-silenced CCA cell lines compared with control vector CCA tumors in mice; these tumors with stable CypA silencing showed a reduced cell proliferation. Conclusions CypA is upregulated in majority of CCA patients' tissues and confers a significant growth advantage in CCA cells. Suppression of CypA expression decreases proliferation of CCA cell lines in vitro and reduces tumor growth in the nude mouse model. Inhibition of Cyp

Active Roles of Tumor Stroma in Breast Cancer Metastasis

International Nuclear Information System (INIS)

Khamis, Z.I.; Sang, Q.A.; Sahab, Z.J.

2012-01-01

Metastasis is the major cause of death for breast cancer patients. Tumors are heterogenous cellular entities composed of cancer cells and cells of the microenvironment in which they reside. A reciprocal dynamic interaction occurs between the tumor cells and their surrounding stroma under physiological and pathological conditions. This tumor-host communication interface mediates the escape of tumor cells at the primary site, survival of circulating cancer cells in the vasculature, and growth of metastatic cancer at secondary site. Each step of the metastatic process is accompanied by recruitment of stromal cells from the microenvironment and production of unique array of growth factors and chemokines. Stromal microenvironment may play active roles in breast cancer metastasis. Elucidating the types of cells recruited and signal pathways involved in the crosstalk between tumor cells and stromal cells will help identify novel strategies for cotargeting cancer cells and tumor stromal cells to suppress metastasis and improve patient outcome

Active Roles of Tumor Stroma in Breast Cancer Metastasis

Directory of Open Access Journals (Sweden)

Zahraa I. Khamis

2012-01-01

Full Text Available Metastasis is the major cause of death for breast cancer patients. Tumors are heterogenous cellular entities composed of cancer cells and cells of the microenvironment in which they reside. A reciprocal dynamic interaction occurs between the tumor cells and their surrounding stroma under physiological and pathological conditions. This tumor-host communication interface mediates the escape of tumor cells at the primary site, survival of circulating cancer cells in the vasculature, and growth of metastatic cancer at secondary site. Each step of the metastatic process is accompanied by recruitment of stromal cells from the microenvironment and production of unique array of growth factors and chemokines. Stromal microenvironment may play active roles in breast cancer metastasis. Elucidating the types of cells recruited and signal pathways involved in the crosstalk between tumor cells and stromal cells will help identify novel strategies for cotargeting cancer cells and tumor stromal cells to suppress metastasis and improve patient outcome.

Natural proteasome inhibitor celastrol suppresses androgen-independent prostate cancer progression by modulating apoptotic proteins and NF-kappaB.

Directory of Open Access Journals (Sweden)

Yao Dai

Full Text Available Celastrol is a natural proteasome inhibitor that exhibits promising anti-tumor effects in human malignancies, especially the androgen-independent prostate cancer (AIPC with constitutive NF-κB activation. Celastrol induces apoptosis by means of proteasome inhibition and suppresses prostate tumor growth. However, the detailed mechanism of action remains elusive. In the current study, we aim to test the hypothesis that celastrol suppresses AIPC progression via inhibiting the constitutive NF-κB activity as well as modulating the Bcl-2 family proteins.We examined the efficacy of celastrol both in vitro and in vivo, and evaluated the role of NF-κB in celastrol-mediated AIPC regression. We found that celastrol inhibited cell proliferation in all three AIPC cell lines (PC-3, DU145 and CL1, with IC₅₀ in the range of 1-2 µM. Celastrol also suppressed cell migration and invasion. Celastrol significantly induced apoptosis as evidenced by increased sub-G1 population, caspase activation and PARP cleavage. Moreover, celastrol promoted cleavage of the anti-apoptotic protein Mcl-1 and activated the pro-apoptotic protein Noxa. In addition, celastrol rapidly blocked cytosolic IκBα degradation and nuclear translocation of RelA. Likewise, celastrol inhibited the expression of multiple NF-κB target genes that are involved in proliferation, invasion and anti-apoptosis. Celastrol suppressed AIPC tumor progression by inhibiting proliferation, increasing apoptosis and decreasing angiogenesis, in PC-3 xenograft model in nude mouse. Furthermore, increased cellular IκBα and inhibited expression of various NF-κB target genes were observed in tumor tissues.Our data suggest that, via targeting the proteasome, celastrol suppresses proliferation, invasion and angiogenesis by inducing the apoptotic machinery and attenuating constitutive NF-κB activity in AIPC both in vitro and in vivo. Celastrol as an active ingredient of traditional herbal medicine could thus be

FAM49B, a novel regulator of mitochondrial function and integrity that suppresses tumor metastasis.

Science.gov (United States)

Chattaragada, M S; Riganti, C; Sassoe, M; Principe, M; Santamorena, M M; Roux, C; Curcio, C; Evangelista, A; Allavena, P; Salvia, R; Rusev, B; Scarpa, A; Cappello, P; Novelli, F

2018-02-08

Mitochondrial dysregulation plays a central role in cancers and drives reactive oxygen species (ROS)-dependent tumor progression. We investigated the pro-tumoral roles of mitochondrial dynamics and altered intracellular ROS levels in pancreatic ductal adenocarcinoma (PDAC). We identified 'family with sequence similarity 49 member B' (FAM49B) as a mitochondria-localized protein that regulates mitochondrial fission and cancer progression. Silencing FAM49B in PDAC cells resulted in increased fission and mitochondrial ROS generation, which enhanced PDAC cell proliferation and invasion. Notably, FAM49B expression levels in PDAC cells were downregulated by the tumor microenvironment. Overall, the results of this study show that FAM49B acts as a suppressor of cancer cell proliferation and invasion in PDAC by regulating tumor mitochondrial redox reactions and metabolism.

Selective Mitochondrial Uptake of MKT-077 Can Suppress Medullary Thyroid Carcinoma Cell Survival and

Directory of Open Access Journals (Sweden)

Dmytro Starenki

2015-12-01

Full Text Available BackgroundMedullary thyroid carcinoma (MTC is a neuroendocrine tumor mainly caused by mutations in the rearranged during transfection (RET proto-oncogene. Not all patients with progressive MTC respond to current therapy inhibiting RET, demanding additional therapeutic strategies. We recently demonstrated that disrupting mitochondrial metabolism using a mitochondria-targeted agent or by depleting a mitochondrial chaperone effectively suppressed human MTC cells in culture and in mouse xenografts by inducing apoptosis and RET downregulation. These observations led us to hypothesize that mitochondria are potential therapeutic targets for MTC. This study further tests this hypothesis using1-ethyl-2-[[3-ethyl-5-(3-methylbenzothiazolin-2-yliden]-4-oxothiazolidin-2-ylidenemethyl] pyridinium chloride (MKT-077, a water-soluble rhodocyanine dye analogue, which can selectively accumulate in mitochondria.MethodsThe effects of MKT-077 on cell proliferation, survival, expression of RET and tumor protein 53 (TP53, and mitochondrial activity were determined in the human MTC lines in culture and in mouse xenografts.ResultsMKT-077 induced cell cycle arrest in TT and MZ-CRC-1. Intriguingly, MKT-077 also induced RET downregulation and strong cell death responses in TT cells, but not in MZ-CRC-1 cells. This discrepancy was mainly due to the difference between the capacities of these cell lines to retain MKT-077 in mitochondria. The cytotoxicity of MKT-077 in TT cells was mainly attributed to oxidative stress while being independent of TP53. MKT-077 also effectively suppressed tumor growth of TT xenografts.ConclusionMKT-077 can suppress cell survival of certain MTC subtypes by accumulating in mitochondria and interfering with mitochondrial activity although it can also suppress cell proliferation via other mechanisms. These results consistently support the hypothesis that mitochondrial targeting has therapeutic potential for MTC.

Metaphyseal giant cell tumor

International Nuclear Information System (INIS)

Pereira, L.F.; Hemais, P.M.P.G.; Aymore, I.L.; Carmo, M.C.R. do; Cunha, M.E.P.R. da; Resende, C.M.C.

1986-01-01

Three cases of metaphyseal giant cell tumor are presented. A review of the literature is done, demostrating the lesion is rare and that there are few articles about it. Age incidence and characteristics of the tumor are discussed. (Author) [pt

RAF Suppression Synergizes with MEK Inhibition in KRAS Mutant Cancer Cells

Directory of Open Access Journals (Sweden)

Simona Lamba

2014-09-01

Full Text Available KRAS is the most frequently mutated oncogene in human cancer, yet no therapies are available to treat KRAS mutant cancers. We used two independent reverse genetic approaches to identify components of the RAS-signaling pathways required for growth of KRAS mutant tumors. Small interfering RNA (siRNA screening of 37 KRAS mutant colorectal cancer cell lines showed that RAF1 suppression was synthetic lethal with MEK inhibition. An unbiased kinome short hairpin RNA (shRNA-based screen confirmed this synthetic lethal interaction in colorectal as well as in lung cancer cells bearing KRAS mutations. Compounds targeting RAF kinases can reverse resistance to the MEK inhibitor selumetinib. MEK inhibition induces RAS activation and BRAF-RAF1 dimerization and sustains MEK-ERK signaling, which is responsible for intrinsic resistance to selumetinib. Prolonged dual blockade of RAF and MEK leads to persistent ERK suppression and efficiently induces apoptosis. Our data underlie the relevance of developing combinatorial regimens of drugs targeting the RAF-MEK pathway in KRAS mutant tumors.

Kefiran suppresses antigen-induced mast cell activation.

Science.gov (United States)

Furuno, Tadahide; Nakanishi, Mamoru

2012-01-01

Kefir is a traditional fermented milk beverage produced by kefir grains in the Caucasian countries. Kefiran produced by Lactobacillus kefiranofaciens in kefir grains is an exopolysaccharide having a repeating structure with glucose and galactose residues in the chain sequence and has been suggested to exert many health-promoting effects such as immunomodulatory, hypotensive, hypocholesterolemic activities. Here we investigated the effects of kefiran on mast cell activation induced by antigen. Pretreatment with kefiran significantly inhibited antigen-induced Ca(2+) mobilization, degranulation, and tumor necrosis factor-α production in bone marrow-derived mast cells (BMMCs) in a dose-dependent manner. The phosphorylation of Akt, glycogen synthase kinase 3β, and extracellular signal-regulated kinases (ERKs) after antigen stimulation was also suppressed by pretreatment of BMMCs with kefiran. These findings indicate that kefiran suppresses mast cell degranulation and cytokine production by inhibiting the Akt and ERKs pathways, suggesting an anti-inflammatory effect for kefiran.

Biological mechanisms of gallium-67 tumor deposition

International Nuclear Information System (INIS)

Okuyama, Shinichi; Takeda, Shumpei; Sato, Tachio; Takusagawa, Kimihiko; Awano, Takayuki.

1979-01-01

This investigation was undertaken in order to clarify the tumor deposition mechanisms of 67 Ga citrate, a ''universal tumor labeler''. An interspecies comparison of various tumors in the rat and mouse indicated that its highest deposition was in the undifferentiated cell type. Amongst the siblings of experimental tumors, cellular membrane negative charge is greater in the free-cell types than the island-formers: a short-term labeling study revealed a greater 67 Ga deposition in the free-cell types. A subcellar fractionation showed an initial association of 67 Ga with the nuclear and membrane fractions, and a later transition to the lysosomal. Hypotonic lysis revealed a paralleled release of 67 Ga and lysosomal key enzymes. Morphological abnormality of the cancer lysosomes was thought to agree with their Ga retention. This property was clinically confirmed by a scintiscoring technique. Treatment with cold gallium of tumors modified the biological parameters of tumor growth: in vitro it suppressed cell proliferation, reduced saturation density; and produced cellular pleomorphism. In vivo it increased tumor consistency by reducing central necrosis and increasing the viable cell layer thickness. Thus, 67 Ga deposition is closely related to various biological parameters of malignancy including the cellular membrane negative charge as cancer is a membrane disorder, and the lysosomal morphology and function. (author)

Imaging of pancreatic tumors

International Nuclear Information System (INIS)

Brambs, Hans-Juergen; Juchems, Markus

2010-01-01

Ductal adenocarcinoma is the most frequent solid tumor of the pancreas. This tumor has distinct features including early obstruction of the pancreatic duct, diminished enhancement after administration of contrast material due to desmoplastic growth, high propensity to infiltrate adjacent structures and to metastasize into the liver and the peritoneum. Hormone active endocrine tumors cause specific clinical symptoms. Imaging is aimed at localization of these hypervascular tumors. Non hormone active tumors are most frequently malignant and demonstrate very varying features. Cystic pancreatic tumors are increasingly detected by means of cross sectional imaging. Exact classification can be achieved with knowledge of the macropathology and considering clinical presentation as well as age and gender of the patients. (orig.)

Synergy between an antiangiogenic integrin αv antagonist and an antibody–cytokine fusion protein eradicates spontaneous tumor metastases

OpenAIRE

Lode, Holger N.; Moehler, Thomas; Xiang, Rong; Jonczyk, Alfred; Gillies, Stephen D.; Cheresh, David A.; Reisfeld, Ralph A.

1999-01-01

The suppression and eradication of primary tumors and distant metastases is a major goal of alternative treatment strategies for cancer, such as inhibition of angiogenesis and targeted immunotherapy. We report here a synergy between two novel monotherapies directed against vascular and tumor compartments, respectively, a tumor vasculature-specific antiangiogenic integrin αv antagonist and tumor-specific antibody–interleukin 2 (IL-2) fusion proteins. Simultaneous an...

miR-409-3p suppresses breast cancer cell growth and invasion by targeting Akt1

Energy Technology Data Exchange (ETDEWEB)

Zhang, Guoqiang [Department of Breast Surgery, Qilu Hospital, Shandong University, Jinan 250012 (China); Department of Thyroid and Breast Surgery, Hospital Affiliated to Binzhou Medical University, 661 Second Huanghe Street, Binzhou 256603 (China); Liu, Zengyan [Department of Hematology, Hospital Affiliated to Binzhou Medical University, 661 Second Huanghe Street, Binzhou 256603 (China); Xu, Hao [Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029 (China); Yang, Qifeng, E-mail: qifengy_sdu1@163.com [Department of Breast Surgery, Qilu Hospital, Shandong University, Jinan 250012 (China)

2016-01-08

Altered levels and functions of microRNAs (miRNAs) are correlated with carcinogenesis. While miR-409-3p has been shown to play important roles in several cancer types, its function in the context of breast cancer (BC) remains unknown. In this study, miR-409-3p was significantly downregulated in BC tissues and cell lines, compared with the corresponding control counterparts. Overexpression of miR-409-3p inhibited BC cell proliferation, migration and invasion in vitro and suppressed tumor growth in vivo. Notably, miR-409-3p induced downregulation of Akt1 protein through binding to its 3′ untranslated region (UTR). Conversely, restoring Akt1 expression rescued the suppressive effects of miR-409-3p. Our data collectively indicate that miR-409-3p functions as a tumor suppressor in BC through downregulating Akt1, supporting the targeting of the novel miR-409-3p/Akt1 axis as a potentially effective therapeutic approach for BC. - Highlights: • miR-409-3p inhibits proliferation, migration and invasion of BC cells. • miR-409-3p suppresses tumor growth in nude mice. • Akt1 is a direct downstream target of miR-409-3p. • Ectopic expression of Akt1 reverses the effects of miR-409-3p on cell proliferation, migration and invasion.

Metformin Antagonizes Cancer Cell Proliferation by Suppressing Mitochondrial-Dependent Biosynthesis.

Directory of Open Access Journals (Sweden)

Takla Griss

2015-12-01

Full Text Available Metformin is a biguanide widely prescribed to treat Type II diabetes that has gained interest as an antineoplastic agent. Recent work suggests that metformin directly antagonizes cancer cell growth through its actions on complex I of the mitochondrial electron transport chain (ETC. However, the mechanisms by which metformin arrests cancer cell proliferation remain poorly defined. Here we demonstrate that the metabolic checkpoint kinases AMP-activated protein kinase (AMPK and LKB1 are not required for the antiproliferative effects of metformin. Rather, metformin inhibits cancer cell proliferation by suppressing mitochondrial-dependent biosynthetic activity. We show that in vitro metformin decreases the flow of glucose- and glutamine-derived metabolic intermediates into the Tricarboxylic Acid (TCA cycle, leading to reduced citrate production and de novo lipid biosynthesis. Tumor cells lacking functional mitochondria maintain lipid biosynthesis in the presence of metformin via glutamine-dependent reductive carboxylation, and display reduced sensitivity to metformin-induced proliferative arrest. Our data indicate that metformin inhibits cancer cell proliferation by suppressing the production of mitochondrial-dependent metabolic intermediates required for cell growth, and that metabolic adaptations that bypass mitochondrial-dependent biosynthesis may provide a mechanism of tumor cell resistance to biguanide activity.

Abundant immunohistochemical expression of dopamine D{sub 2} receptor and p53 protein in meningiomas: follow-up, relation to gender, age, tumor grade, and recurrence

Energy Technology Data Exchange (ETDEWEB)

Trott, G.; Pereira-Lima, J.F.S.; Leães, C.G.S. [Programa de Graduação em Patologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Centro de Neuroendocrinologia, Complexo Hospitalar Santa Casa de Porto Alegre, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Ferreira, N.P. [Centro de Neuroendocrinologia, Complexo Hospitalar Santa Casa de Porto Alegre, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Barbosa-Coutinho, L.M. [Programa de Graduação em Patologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Oliveira, M.C. [Programa de Graduação em Patologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Centro de Neuroendocrinologia, Complexo Hospitalar Santa Casa de Porto Alegre, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil)

2015-03-03

Meningiomas are common, usually benign tumors, with a high postoperative recurrence rate. However, the genesis and development of these tumors remain controversial. We aimed to investigate the presence and implications of a mutated p53 protein and dopamine D{sub 2} receptor in a representative series of meningiomas and to correlate these findings with age, gender, tumor grade, and recurrence. Tumor tissue samples of 157 patients diagnosed with meningioma (37 males and 120 females, mean age 53.6±14.3 years) who underwent surgical resection between 2003 and 2012 at our institution were immunohistochemically evaluated for the presence of p53 protein and dopamine D{sub 2} receptor and were followed-up to analyze tumor recurrence or regrowth. Tumors were classified as grades I (n=141, 89.8%), II (n=13, 8.3%), or grade III (n=3, 1.9%). Dopamine D{sub 2} receptor and p53 protein expression were positive in 93.6% and 49.7% of the cases, respectively. Neither of the markers showed significant expression differences among different tumor grades or recurrence or regrowth statuses. Our findings highlight the potential role of p53 protein in meningioma development and/or progression. The high positivity of dopamine D{sub 2} receptor observed in this study warrants further investigation of the therapeutic potential of dopamine agonists in the evolution of meningiomas.

Tumor-specific CD4+ T cells develop cytotoxic activity and eliminate virus-induced tumor cells in the absence of regulatory T cells.

Science.gov (United States)

Akhmetzyanova, Ilseyar; Zelinskyy, Gennadiy; Schimmer, Simone; Brandau, Sven; Altenhoff, Petra; Sparwasser, Tim; Dittmer, Ulf

2013-02-01

The important role of tumor-specific cytotoxic CD8(+) T cells is well defined in the immune control of the tumors, but the role of effector CD4(+) T cells is poorly understood. In the current research, we have used a murine retrovirus-induced tumor cell line of C57BL/6 mouse origin, namely FBL-3 cells, as a model to study basic mechanisms of immunological control and escape during tumor formation. This study shows that tumor-specific CD4(+) T cells are able to protect against virus-induced tumor cells. We show here that there is an expansion of tumor-specific CD4(+) T cells producing cytokines and cytotoxic molecule granzyme B (GzmB) in the early phase of tumor growth. Importantly, we demonstrate that in vivo depletion of regulatory T cells (Tregs) and CD8(+) T cells in FBL-3-bearing DEREG transgenic mice augments IL-2 and GzmB production by CD4(+) T cells and increases FV-specific CD4(+) T-cell effector and cytotoxic responses leading to the complete tumor regression. Therefore, the capacity to reject tumor acquired by tumor-reactive CD4(+) T cells largely depends on the direct suppressive activity of Tregs. We suggest that a cytotoxic CD4(+) T-cell immune response may be induced to enhance resistance against oncovirus-associated tumors.

The epigenetic modifier PRDM5 functions as a tumor suppressor through modulating WNT/β-catenin signaling and is frequently silenced in multiple tumors.

Directory of Open Access Journals (Sweden)

Xing-sheng Shu

Full Text Available BACKGROUND: PRDM (PRDI-BF1 and RIZ domain containing proteins are zinc finger proteins involved in multiple cellular regulations by acting as epigenetic modifiers. We studied a recently identified PRDM member PRDM5 for its epigenetic abnormality and tumor suppressive functions in multiple tumorigeneses. METHODOLOGY/PRINCIPAL FINDINGS: Semi-quantitative RT-PCR showed that PRDM5 was broadly expressed in human normal tissues, but frequently silenced or downregulated in multiple carcinoma cell lines due to promoter CpG methylation, including 80% (4/5 nasopharyngeal, 44% (8/18 esophageal, 76% (13/17 gastric, 50% (2/4 cervical, and 25% (3/12 hepatocellular carcinoma cell lines, but not in any immortalized normal epithelial cell lines. PRDM5 expression could be restored by 5-aza-2'-deoxycytidine demethylation treatment in silenced cell lines. PRDM5 methylation was frequently detected by methylation-specific PCR (MSP in multiple primary tumors, including 93% (43/46 nasopharyngeal, 58% (25/43 esophageal, 88% (37/42 gastric and 63% (29/46 hepatocellular tumors. PRDM5 was further found a stress-responsive gene, but its response was impaired when the promoter was methylated. Ectopic PRDM5 expression significantly inhibited tumor cell clonogenicity, accompanied by the inhibition of TCF/β-catenin-dependent transcription and downregulation of CDK4, TWIST1 and MDM2 oncogenes, while knocking down of PRDM5 expression lead to increased cell proliferation. ChIP assay showed that PRDM5 bound to its target gene promoters and suppressed their transcription. An inverse correlation between the expression of PRDM5 and activated β-catenin was also observed in cell lines. CONCLUSIONS/SIGNIFICANCE: PRDM5 functions as a tumor suppressor at least partially through antagonizing aberrant WNT/β-catenin signaling and oncogene expression. Frequent epigenetic silencing of PRDM5 is involved in multiple tumorigeneses, which could serve as a tumor biomarker.

Complete suppression of viral gene expression is associated with the onset and progression of lymphoid malignancy: observations in Bovine Leukemia Virus-infected sheep

Directory of Open Access Journals (Sweden)

Burny Arsène

2007-07-01

Full Text Available Abstract Background During malignant progression, tumor cells need to acquire novel characteristics that lead to uncontrolled growth and reduced immunogenicity. In the Bovine Leukemia Virus-induced ovine leukemia model, silencing of viral gene expression has been proposed as a mechanism leading to immune evasion. However, whether proviral expression in tumors is completely suppressed in vivo was not conclusively demonstrated. Therefore, we studied viral expression in two selected experimentally-infected sheep, the virus or the disease of which had features that made it possible to distinguish tumor cells from their nontransformed counterparts. Results In the first animal, we observed the emergence of a genetically modified provirus simultaneously with leukemia onset. We found a Tax-mutated (TaxK303 replication-deficient provirus in the malignant B-cell clone while functional provirus (TaxE303 had been consistently monitored over the 17-month aleukemic period. In the second case, both non-transformed and transformed BLV-infected cells were present at the same time, but at distinct sites. While there was potentially-active provirus in the non-leukemic blood B-cell population, as demonstrated by ex-vivo culture and injection into naïve sheep, virus expression was completely suppressed in the malignant B-cells isolated from the lymphoid tumors despite the absence of genetic alterations in the proviral genome. These observations suggest that silencing of viral genes, including the oncoprotein Tax, is associated with tumor onset. Conclusion Our findings suggest that silencing is critical for tumor progression and identify two distinct mechanisms-genetic and epigenetic-involved in the complete suppression of virus and Tax expression. We demonstrate that, in contrast to systems that require sustained oncogene expression, the major viral transforming protein Tax can be turned-off without reversing the transformed phenotype. We propose that suppression

The clinical factors associated with benign renal tumors

International Nuclear Information System (INIS)

Yamashita, Ryo; Nakamura, Masafumi; Matsuzaki, Masato; Matsui, Takashi; Yamaguchi, Raizo; Niwakawa, Masashi; Tobisu, Kenichi; Asakura, Koiku; Ito, Ichiro

2009-01-01

In this study, we sought to define the incidence of benign renal tumors in our institute and to clarify the clinical factors associated with benign renal tumors, in order to assist in forming preoperative differential diagnoses. From October 2002 to July 2007, we performed 157 nephrectomies in patients preoperatively diagnosed with renal cell carcinoma. We chose 81 tumors, all of which were less than 5 cm, for further study. We reviewed double-phase helical CT imaging retrospectively, specifically focusing on attenuation patterns and homogeneity. We also compared clinical factors, including age, sex and tumor size, between the benign and malignant renal tumors. The patient's median age was 67 years (mean age, 63 years), and the median tumor diameter was 3.0 cm (mean, 3.2 cm). Benign renal tumors were found in 10 (12%) of the 81 tumors; these included seven cases of oncocytoma and three cases of angiomyolipoma with minimal fat. Several factors were significant clinical determinants of differentiation between benign and malignant renal tumors: homogeneity in CT, female gender, and small tumor size all predominated in cases of benign tumors. Attenuation pattern in CT, however, was not a significant factor (p=0.344). When a patient, especially a female, presents with a small and homogeneous renal tumor, careful consideration should be given to the possibility of a benign process, which needs further consideration before performing excessive surgery. (author)

Mitochondria-Targeted Nitroxide, Mito-CP, Suppresses Medullary Thyroid Carcinoma Cell Survival In Vitro and In Vivo

Science.gov (United States)

Starenki, Dmytro

2013-01-01

Context: Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor mainly caused by mutations in the RET proto-oncogene. For MTC therapy, the U.S. Food and Drug Administration recently approved vandetanib and cabozantinib, multikinase inhibitors targeting RET and other tyrosine kinase receptors of vascular endothelial growth factor, epidermal growth factor, or hepatocyte growth factor. Nevertheless, not all patients with the progressive MTC respond to these drugs, requiring the development of additional therapeutic modalities that have distinct activity. Objective: We aimed to evaluate mitochondria-targeted carboxy-proxyl (Mito-CP), a mitochondria-targeted redox-sensitive agent, for its tumor-suppressive efficacy against MTC. Design: In vitro cultures of 2 human MTC cell lines, TT and MZ-CRC-1, and TT xenografts in mice were treated with Mito-CP in comparison with vandetanib. The effects on cell survival/death, RET expression, mitochondrial integrity, and oxidative stress were determined. Results: Contrary to vandetanib, Mito-CP induced RET downregulation and strong cytotoxic effects in both cell lines in vitro, including caspase-dependent apoptosis. These effects were accompanied by mitochondrial membrane depolarization, decreased oxygen consumption, and increased oxidative stress in cells. Intriguingly, Mito-CP–induced cell death, but not RET downregulation, was partially inhibited by the reactive oxygen species scavenger, N-acetyl-cysteine, indicating that Mito-CP mediates tumor-suppressive effects via redox-dependent as well as redox-independent mechanisms. Orally administered Mito-CP effectively suppressed TT xenografts in mice, with an efficacy comparable to vandetanib and relatively low toxicity to animals. Conclusion: Our results suggest that Mito-CP can effectively suppress MTC cell growth/survival via a mechanism distinct from vandetanib effects. Mitochondrial targeting may be a potential strategy for MTC therapy. PMID:23509102

Dichloroacetate induces tumor-specific radiosensitivity in vitro but attenuates radiation-induced tumor growth delay in vivo

Energy Technology Data Exchange (ETDEWEB)

Zwicker, F.; Roeder, F.; Debus, J.; Huber, P.E. [University Hospital Center Heidelberg, Heidelberg (Germany). Dept. of Radiation Oncology; Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Clinical Cooperation Unit Molecular Radiation Oncology; Kirsner, A.; Weber, K.J. [University Hospital Center Heidelberg, Heidelberg (Germany). Dept. of Radiation Oncology; Peschke, P. [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Clinical Cooperation Unit Molecular Radiation Oncology

2013-08-15

Background: Inhibition of pyruvate dehydrogenase kinase (PDK) by dichloroacetate (DCA) can shift tumor cell metabolism from anaerobic glycolysis to glucose oxidation, with activation of mitochondrial activity and chemotherapy-dependent apoptosis. In radiotherapy, DCA could thus potentially enhance the frequently moderate apoptotic response of cancer cells that results from their mitochondrial dysfunction. The aim of this study was to investigate tumor-specific radiosensitization by DCA in vitro and in a human tumor xenograft mouse model in vivo. Materials and methods: The interaction of DCA with photon beam radiation was investigated in the human tumor cell lines WIDR (colorectal) and LN18 (glioma), as well as in the human normal tissue cell lines HUVEC (endothelial), MRC5 (lung fibroblasts) and TK6 (lymphoblastoid). Apoptosis induction in vitro was assessed by DAPI staining and sub-G1 flow cytometry; cell survival was quantified by clonogenic assay. The effect of DCA in vivo was investigated in WIDR xenograft tumors growing subcutaneously on BALB/c-nu/nu mice, with and without fractionated irradiation. Histological examination included TUNEL and Ki67 staining for apoptosis and proliferation, respectively, as well as pinomidazole labeling for hypoxia. Results: DCA treatment led to decreased clonogenic survival and increased specific apoptosis rates in tumor cell lines (LN18, WIDR) but not in normal tissue cells (HUVEC, MRC5, TK6). However, this significant tumor-specific radiosensitization by DCA in vitro was not reflected by the situation in vivo: The growth suppression of WIDR xenograft tumors after irradiation was reduced upon additional DCA treatment (reflected by Ki67 expression levels), although early tumor cell apoptosis rates were significantly increased by DCA. This apparently paradoxical effect was accompanied by a marked DCA-dependent induction of hypoxia in tumor-tissue. Conclusion: DCA induced tumor-specific radiosensitization in vitro but not in vivo

A comparative study of proliferative activity and tumor stage of pregnancy-associated melanoma (PAM) and non-PAM in gestational age women.

Science.gov (United States)

Merkel, Emily A; Martini, Mary C; Amin, Sapna M; Yélamos, Oriol; Lee, Christina Y; Sholl, Lauren M; Rademaker, Alfred W; Guitart, Joan; Gerami, Pedram

2016-01-01

The influence of pregnancy on the development, progression, and prognosis of melanoma is controversial. We sought to compare clinical characteristics, histologic features, and proliferative activity in pregnancy-associated melanoma (PAM) and melanoma in nonpregnant women of reproductive age (non-PAM). In this retrospective cohort study, we reviewed medical records and pathology reports from women given a diagnosis of melanoma between 2006 and 2015. We also examined tumor proliferation rates using mitotic count and 2 immunohistochemical markers of proliferation, phosphohistone H3 and Ki-67. In 50 PAM and 122 non-PAM cases, a diagnosis of melanoma in situ was associated with PAM. Among invasive melanomas, there was no difference in proliferative activity between groups. Pregnancy status was also not associated with age at diagnosis, tumor site, Breslow depth, Clark level, ulceration, or overall stage. This was a retrospective study with a small sample size of mostly patients with early-stage melanoma. In our study of primarily early-stage melanoma, pregnancy did not have a significant impact on tumor proliferation. Particularly for patients given a diagnosis of stage I melanoma who are undergoing close surveillance, a history of PAM should not outweigh traditional factors, such as advanced maternal age, in planning future pregnancies. Copyright © 2015 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Maturation of cognitive control: delineating response inhibition and interference suppression.

Directory of Open Access Journals (Sweden)

Christopher R Brydges

Full Text Available Cognitive control is integral to the ability to attend to a relevant task whilst suppressing distracting information or inhibiting prepotent responses. The current study examined the development of these two subprocesses by examining electrophysiological indices elicited during each process. Thirteen 18 year-old adults and thirteen children aged 8-11 years (mean=9.77 years completed a hybrid Go/Nogo flanker task while continuous EEG data were recorded. The N2 topography for both response inhibition and interference suppression changed with increasing age. The neural activation associated with response inhibition became increasingly frontally distributed with age, and showed decreases of both amplitude and peak latency from childhood to adulthood, possibly due to reduced cognitive demands and myelination respectively occurring during this period. Interestingly, a significant N2 effect was apparent in adults, but not observed in children during trials requiring interference suppression. This could be due to more diffuse activation in children, which would require smaller levels of activation over a larger region of the brain than is reported in adults. Overall, these results provide evidence of distinct maturational processes occurring throughout late childhood and adolescence, highlighting the separability of response inhibition and interference suppression.

Novel effector phenotype of Tim-3+ regulatory T cells leads to enhanced suppressive function in head and neck cancer patients.

Science.gov (United States)

Liu, Zhuqing; McMichael, Elizabeth L; Shayan, Gulidanna; Li, Jing; Chen, Kevin; Srivastava, Raghvendra M; Kane, Lawrence P; Lu, Binfeng; Ferris, Robert L

2018-04-30

Regulatory T (Treg) cells are important suppressive cells among tumor infiltrating lymphocytes (TIL). Treg express the well-known immune checkpoint receptor PD-1, which is reported to mark "exhausted" Treg with lower suppressive function. T cell immunoglobulin mucin (Tim)-3, a negative regulator of Th1 immunity, is expressed by a sizeable fraction of TIL Tregs, but the functional status of Tim-3+ Tregs remains unclear. CD4+CTLA-4+CD25high Treg were sorted from freshly excised head and neck squamous cell carcinoma (HNSCC) TIL based on Tim-3 expression. Functional and phenotypic features of these Tim-3+ and Tim-3- TIL Tregs were tested by in vitro suppression assays and multi-color flow cytometry. Gene expression profiling and NanoString analysis of Tim-3+ TIL Treg were performed. A murine HNSCC tumor model was used to test the effect of anti-PD-1 immunotherapy on Tim-3+ Treg.  Results: Despite high PD-1 expression, Tim-3+ TIL Treg displayed a greater capacity to inhibit naïve T cell proliferation than Tim-3- Treg. Tim-3+ Treg from human HNSCC TIL also displayed an effector-like phenotype, with more robust expression of CTLA-4, PD-1, CD39 and IFN-γ receptor. Exogenous IFN-γ treatment could partially reverse the suppressive function of Tim-3+ TIL Treg. Anti-PD-1 immunotherapy downregulated Tim-3 expression on Tregs isolated from murine HNSCC tumors, and this treatment reversed the suppressive function of HNSCC TIL Tregs. Tim-3+ Treg are functionally and phenotypically distinct in HNSCC TIL, and are highly effective at inhibiting T cell proliferation despite high PD-1 expression.  IFN-γ induced by anti-PD-1 immunotherapy may be beneficial by reversing Tim-3+ Treg suppression. Copyright ©2018, American Association for Cancer Research.

FOXD3 suppresses tumor growth and angiogenesis in non-small cell lung cancer

International Nuclear Information System (INIS)

Yan, Jun-Hai; Zhao, Chun-Liu; Ding, Lan-Bao; Zhou, Xi

2015-01-01

The transcription factor forkhead box D3 (FOXD3), widely studied as a transcriptional repressor in embryogenesis, participates in the carcinogenesis of many cancers. However, the expression pattern and role of FOXD3 in non-small cell lung cancer (NSCLC) have not been well characterized. We report that FOXD3 is significantly downregulated in NSCLC cell lines and clinical tissues. FOXD3 overexpression significantly inhibits cell growth and results in G1 cell cycle arrest in NSCLC A549 and H1299 cells. In a xenograft tumor model, FOXD3 overexpression inhibits tumor growth and angiogenesis. Remarkably, expression of vascular endothelial growth factor (VEGF) was reduced in FOXD3 overexpression models both in vitro and in vivo. These findings suggest that FOXD3 plays a potential tumor suppressor role in NSCLC progression and represents a promising clinical prognostic marker and therapeutic target for this disease. - Highlights: • FOXD3 is downregulated in NSCLC cell lines and tissues. • FOXD3 overexpression inhibited cell proliferation in NSCLC cells. • FOXD3 overexpression led to decreased angiogenesis in NSCLC cells in vitro and in vivo.

FOXD3 suppresses tumor growth and angiogenesis in non-small cell lung cancer

Energy Technology Data Exchange (ETDEWEB)

Yan, Jun-Hai; Zhao, Chun-Liu [Department of Respiratory Medicine, Luwan Branch of Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 20020 (China); Ding, Lan-Bao [Department of Nuclear Medicine, Shanghai 10th People' s Hospital, Tongji University School of Medicine, Shanghai 200072 (China); Zhou, Xi, E-mail: modelmap@139.com [Department of Respiratory Medicine, Luwan Branch of Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 20020 (China)

2015-10-09

The transcription factor forkhead box D3 (FOXD3), widely studied as a transcriptional repressor in embryogenesis, participates in the carcinogenesis of many cancers. However, the expression pattern and role of FOXD3 in non-small cell lung cancer (NSCLC) have not been well characterized. We report that FOXD3 is significantly downregulated in NSCLC cell lines and clinical tissues. FOXD3 overexpression significantly inhibits cell growth and results in G1 cell cycle arrest in NSCLC A549 and H1299 cells. In a xenograft tumor model, FOXD3 overexpression inhibits tumor growth and angiogenesis. Remarkably, expression of vascular endothelial growth factor (VEGF) was reduced in FOXD3 overexpression models both in vitro and in vivo. These findings suggest that FOXD3 plays a potential tumor suppressor role in NSCLC progression and represents a promising clinical prognostic marker and therapeutic target for this disease. - Highlights: • FOXD3 is downregulated in NSCLC cell lines and tissues. • FOXD3 overexpression inhibited cell proliferation in NSCLC cells. • FOXD3 overexpression led to decreased angiogenesis in NSCLC cells in vitro and in vivo.

A PAUF-neutralizing antibody targets both carcinoma and endothelial cells to impede pancreatic tumor progression and metastasis

Energy Technology Data Exchange (ETDEWEB)

Kim, Su Jin [Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); New Drug Development Center, Osong Medical Innovation Foundation, Cheongwon, Chungbuk (Korea, Republic of); Chang, Suhwan [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Lee, Yangsoon; Kim, Na Young; Hwang, Yeonsil; Min, Hye Jin; Yoo, Kyung-Sook; Park, Eun Hye; Kim, Seokho [Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Chung, Young-Hwa [BK21-plus, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan (Korea, Republic of); Park, Young Woo [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Koh, Sang Seok, E-mail: sskoh@dau.ac.kr [Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Department of Biological Sciences, Dong-A University, Busan (Korea, Republic of)

2014-11-07

Highlights: • PMAb83, a human monoclonal antibody against PAUF, impaired tumor progression in vivo. • PMAb83 attenuated aggressiveness of tumor cells and suppressed angiogenesis. • PMAb83 in combination with gemcitabine conferred improved survival of mouse model. - Abstract: Pancreatic adenocarcinoma up-regulated factor (PAUF) is expressed in pancreatic ductal adenocarcinoma (PDAC) and plays an important role in tumor progression and metastasis. Here we evaluate the anti-tumor efficacy of a human monoclonal antibody against PAUF, PMAb83, to provide a therapeutic intervention to treat the disease. PMAb83 reduced tumor growth and distant metastasis in orthotopically xenografted mice of human PDAC cells. PMAb83 treatment retarded proliferation along with weakened aggressiveness traits of the carcinoma cells. AKT/β-catenin signaling played a role in the carcinoma cell proliferation and the treated xenograft tumors exhibited reduced levels of β-catenin and cyclin D1. Moreover PMAb83 abrogated the PAUF-induced angiogenic responses of endothelial cells, reducing the density of CD31{sup +} vessels in the treated tumors. In combination with gemcitabine, PMAb83 conferred enhanced survival of xenografted mice by about twofold compared to gemcitabine alone. Taken together, our findings show that PMAb83 treatment decreases the aggressiveness of carcinoma cells and suppresses tumor vascularization, which culminates in mitigated tumor growth and metastasis with improved survival in PDAC mouse models.

A PAUF-neutralizing antibody targets both carcinoma and endothelial cells to impede pancreatic tumor progression and metastasis

International Nuclear Information System (INIS)

Kim, Su Jin; Chang, Suhwan; Lee, Yangsoon; Kim, Na Young; Hwang, Yeonsil; Min, Hye Jin; Yoo, Kyung-Sook; Park, Eun Hye; Kim, Seokho; Chung, Young-Hwa; Park, Young Woo; Koh, Sang Seok

2014-01-01

Highlights: • PMAb83, a human monoclonal antibody against PAUF, impaired tumor progression in vivo. • PMAb83 attenuated aggressiveness of tumor cells and suppressed angiogenesis. • PMAb83 in combination with gemcitabine conferred improved survival of mouse model. - Abstract: Pancreatic adenocarcinoma up-regulated factor (PAUF) is expressed in pancreatic ductal adenocarcinoma (PDAC) and plays an important role in tumor progression and metastasis. Here we evaluate the anti-tumor efficacy of a human monoclonal antibody against PAUF, PMAb83, to provide a therapeutic intervention to treat the disease. PMAb83 reduced tumor growth and distant metastasis in orthotopically xenografted mice of human PDAC cells. PMAb83 treatment retarded proliferation along with weakened aggressiveness traits of the carcinoma cells. AKT/β-catenin signaling played a role in the carcinoma cell proliferation and the treated xenograft tumors exhibited reduced levels of β-catenin and cyclin D1. Moreover PMAb83 abrogated the PAUF-induced angiogenic responses of endothelial cells, reducing the density of CD31 + vessels in the treated tumors. In combination with gemcitabine, PMAb83 conferred enhanced survival of xenografted mice by about twofold compared to gemcitabine alone. Taken together, our findings show that PMAb83 treatment decreases the aggressiveness of carcinoma cells and suppresses tumor vascularization, which culminates in mitigated tumor growth and metastasis with improved survival in PDAC mouse models

Juvenile nasopharyngeal angiofibroma - study of the tumor extension and vascularization through computerized tomography (CT) scan and angiography and the patient's age

International Nuclear Information System (INIS)

Sennes, Luiz Ubirajara

1997-01-01

The juvenile nasopharyngeal angiofibroma is a rare benign tumor that affects male adolescents. It is a fibro-vascular tumor with an exuberant intra tumor blood flow and irrigated by several arteries. It originates from the lateral and posterior region of the nasal cavity and, due to its characteristic multidirectional growth, widely affects the paranasal sinuses and skull base, sometimes invading the cranial fossa or the cheek. The determinant factors of its growth and vascularisation are unknown. Attempting to clarify them, 33 patients from the University of Sao Paulo Medicine were studied from 1983 to 1995, with complete history and radiological documentation (CT scan and angiography), as well as with histological confirmation of the diagnosis. In order to take only tumors with natural evolution, patients with recidivant tumor and those already submitted to any previous treatment were excluded. The parameters evaluate were: patient age and tumor extension (by classification, degree of invasion and number of compromised sites in CT scan) and vascularisation (by number and degree of participation of bilateral arteries in angiography). The se data were tabled and correlated one with each other. (author)

Kinase fusions are frequent in Spitz tumors and spitzoid melanomas

Science.gov (United States)

Esteve-Puig, Rosaura; Botton, Thomas; Yeh, Iwei; Lipson, Doron; Otto, Geoff; Brennan, Kristina; Murali, Rajmohan; Garrido, Maria; Miller, Vincent A.; Ross, Jeffrey S; Berger, Michael F.; Sparatta, Alyssa; Palmedo, Gabriele; Cerroni, Lorenzo; Busam, Klaus J.; Kutzner, Heinz; Cronin, Maureen T; Stephens, Philip J; Bastian, Boris C.

2014-01-01

Spitzoid neoplasms are a group of melanocytic tumors with distinctive histopathologic features. They include benign tumors (Spitz nevi), malignant tumors (spitzoid melanomas), and tumors with borderline histopathologic features and uncertain clinical outcome (atypical Spitz tumors). Their genetic underpinnings are poorly understood, and alterations in common melanoma-associated oncogenes are typically absent. Here we show that spitzoid neoplasms harbor kinase fusions of ROS1 (17%), NTRK1 (16%), ALK (10%), BRAF (5%), and RET (3%) in a mutually exclusive pattern. The chimeric proteins are constitutively active, stimulate oncogenic signaling pathways, are tumorigenic, and are found in the entire biologic spectrum of spitzoid neoplasms, including 55% of Spitz nevi, 56% of atypical Spitz tumors, and 39% of spitzoid melanomas. Kinase inhibitors suppress the oncogenic signaling of the fusion proteins in vitro. In summary, kinase fusions account for the majority of oncogenic aberrations in spitzoid neoplasms, and may serve as therapeutic targets for metastatic spitzoid melanomas. PMID:24445538

Verbal Memory Impairments in Children after Cerebellar Tumor Resection

Directory of Open Access Journals (Sweden)

Matthew P. Kirschen

2008-01-01

Full Text Available This study was designed to investigate cerebellar lobular contributions to specific cognitive deficits observed after cerebellar tumor resection. Verbal working memory (VWM tasks were administered to children following surgical resection of cerebellar pilocytic astrocytomas and age-matched controls. Anatomical MRI scans were used to quantify the extent of cerebellar lobular damage from each patient's resection. Patients exhibited significantly reduced digit span for auditory but not visual stimuli, relative to controls, and damage to left hemispheral lobule VIII was significantly correlated with this deficit. Patients also showed reduced effects of articulatory suppression and this was correlated with damage to the vermis and hemispheral lobule IV/V bilaterally. Phonological similarity and recency effects did not differ overall between patients and controls, but outlier patients with abnormal phonological similarity effects to either auditory or visual stimuli were found to have damage to hemispheral lobule VIII/VIIB on the left and right, respectively. We postulate that damage to left hemispheral lobule VIII may interfere with encoding of auditory stimuli into the phonological store. These data corroborate neuroimaging studies showing focal cerebellar activation during VWM paradigms, and thereby allow us to predict with greater accuracy which specific neurocognitive processes will be affected by a cerebellar tumor resection.

[Malignant nonepithelial tumors of the lung].

Science.gov (United States)

Trakhtenberg, A Kh; Biriukov, Iu V; Frank, G A; Kunitsyn, A G; Grigor'eva, S P; Aĭtakov, Z N; Korenev, S V; Efimova, O Iu; Vial'tsev, N V

1990-01-01

The main peculiarities of the clinical course of lung sarcoma were determined from representative material of 134 patients. The main features differentiating malignant nonepithelial tumors from carcinoma of the lung are: younger age (average age 45.5 years), predominantly peripheral clinico-anatomical form (82.8%), and prevalent hematogenic metastasis. Five-year survival in the whole group of patients after surgical treatment was 54%. The size and histological form of the tumor are the main factors of prognosis. The degree of differentiation acquires prognostic significance in tumors measuring more than 3 cm in diameter.

Brain tumors and syndromes in children

NARCIS (Netherlands)

Bleeker, Fonnet E.; Hopman, Saskia M. J.; Merks, Johannes H. M.; Aalfs, Cora M.; Hennekam, Raoul C. M.

2014-01-01

(Brain) tumors are usually a disorder of aged individuals. If a brain tumor occurs in a child, there is a possible genetic susceptibility for this. Such genetic susceptibilities often show other signs and symptoms. Therefore, every child with a brain tumor should be carefully evaluated for the

The current status of studies on mitochondrial DNA with tumor, radiation biological effects and aging

International Nuclear Information System (INIS)

Liu Qingjie; Sang Lu

2004-01-01

The mitochondrial plays a very important role in sustaining the normal physiological function, because it is the center of energy making and mitochondrial DNA (mtDNA) is the only genetic material outside the nuclear. The result of studies showed that many diseases have a close relationship with mtDNA mutation and deletion. This article reviewed the current status of research on mtDNA with tumor, radiation biological effects and aging, in order to initiate the application study of mtDNA in the circle of radiation medicine

Anti-SEMA3A Antibody: A Novel Therapeutic Agent to Suppress GBM Tumor Growth.

Science.gov (United States)

Lee, Jaehyun; Shin, Yong Jae; Lee, Kyoungmin; Cho, Hee Jin; Sa, Jason K; Lee, Sang-Yun; Kim, Seok-Hyung; Lee, Jeongwu; Yoon, Yeup; Nam, Do-Hyun

2017-11-10

Glioblastoma (GBM) is classified as one of the most aggressive and lethal brain tumor. Great strides have been made in understanding the genomic and molecular underpinnings of GBM, which translated into development of new therapeutic approaches to combat such deadly disease. However, there are only few therapeutic agents that can effectively inhibit GBM invasion in a clinical framework. In an effort to address such challenges, we have generated anti-SEMA3A monoclonal antibody as a potential therapeutic antibody against GBM progression. We employed public glioma datasets, Repository of Molecular Brain Neoplasia Data and The Cancer Genome Atlas, to analyze SEMA3A mRNA expression in human GBM specimens. We also evaluated for protein expression level of SEMA3A via tissue microarray (TMA) analysis. Cell migration and proliferation kinetics were assessed in various GBM patient-derived cells (PDCs) and U87-MG cell-line for SEMA3A antibody efficacy. GBM patient-derived xenograft (PDX) models were generated to evaluate tumor inhibitory effect of anti-SEMA3A antibody in vivo. By combining bioinformatics and TMA analysis, we discovered that SEMA3A is highly expressed in human GBM specimens compared to non-neoplastic tissues. We developed three different anti-SEMA3A antibodies, in fully human IgG form, through screening phage-displayed synthetic antibody library using a classical panning method. Neutralization of SEMA3A significantly reduced migration and proliferation capabilities of PDCs and U87-MG cell-line in vitro. In PDX models, treatment with anti-SEMA3A antibody exhibited notable tumor inhibitory effect through down-regulation of cellular proliferative kinetics and tumor-associated macrophages recruitment. In present study, we demonstrated tumor inhibitory effect of SEMA3A antibody in GBM progression and present its potential relevance as a therapeutic agent in a clinical framework.

The Necrosome Promotes Pancreas Oncogenesis via CXCL1 and Mincle Induced Immune Suppression

Science.gov (United States)

Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Barilla, Rocky; Daley, Donnele; Greco, Stephanie H.; Torres-Hernandez, Alejandro; Pergamo, Matthew; Ochi, Atsuo; Zambirinis, Constantinos P.; Pansari, Mridul; Rendon, Mauricio; Tippens, Daniel; Hundeyin, Mautin; Mani, Vishnu R.; Hajdu, Cristina; Engle, Dannielle; Miller, George

2016-01-01

Neoplastic pancreatic epithelial cells are widely believed to die via Caspase 8-dependant apoptotic cell death and chemotherapy is thought to further promote tumor apoptosis1. Conversely, disruption of apoptosis is a basic modality cancer cells exploit for survival2,3. However, the role of necroptosis, or programmed necrosis, in pancreatic ductal adenocarcinoma (PDA) is uncertain. There are a multitude of potential inducers of necroptosis in PDA including ligation of TNFR1, CD95, TRAIL receptors, Toll-like receptors, ROS, and Chemotherapeutics4,5. Here we report that the principal components of the necrosome, RIP1 and RIP3, are highly expressed in PDA and are further upregulated by chemotherapy. Blockade of the necrosome in vitro promoted cancer cell proliferation and induced an aggressive oncogenic phenotype. By contrast, in vivo RIP3 deletion or RIP1 inhibition was protective against oncogenic progression and was associated with the development of a highly immunogenic myeloid and T cell infiltrate. The immune-suppressive tumor microenvironment (TME) associated with intact RIP1/RIP3 signaling was in-part contingent on necroptosis-induced CXCL1 expression whereas CXCL1 blockade was protective against PDA. Moreover, we found that cytoplasmic SAP130 was expressed in PDA in a RIP1/RIP3-dependent manner, and Mincle – its cognate receptor – was upregulated in tumor-infiltrating myeloid cells. Mincle ligation by SAP130 promoted oncogenesis whereas Mincle deletion was protective and phenocopied the immunogenic reprogramming of the TME characteristic of RIP3 deletion. Cellular depletion experiments suggested that whereas inhibitory macrophages promote tumorigenesis in PDA, they lose their immune-suppressive effects in the context of RIP3 or Mincle deletion. As such, T cells which are dispensable to PDA progression in hosts with intact RIP3 or Mincle signaling become reprogrammed into indispensable mediators of anti-tumor immunity in absence of RIP3 or Mincle. Our work

Modeling and Analysis of a Nonlinear Age-Structured Model for Tumor Cell Populations with Quiescence

Science.gov (United States)

Liu, Zijian; Chen, Jing; Pang, Jianhua; Bi, Ping; Ruan, Shigui

2018-05-01

We present a nonlinear first-order hyperbolic partial differential equation model to describe age-structured tumor cell populations with proliferating and quiescent phases at the avascular stage in vitro. The division rate of the proliferating cells is assumed to be nonlinear due to the limitation of the nutrient and space. The model includes a proportion of newborn cells that enter directly the quiescent phase with age zero. This proportion can reflect the effect of treatment by drugs such as erlotinib. The existence and uniqueness of solutions are established. The local and global stabilities of the trivial steady state are investigated. The existence and local stability of the positive steady state are also analyzed. Numerical simulations are performed to verify the results and to examine the impacts of parameters on the nonlinear dynamics of the model.

Anti- and pro-tumor functions of autophagy.

Science.gov (United States)

Morselli, Eugenia; Galluzzi, Lorenzo; Kepp, Oliver; Vicencio, José-Miguel; Criollo, Alfredo; Maiuri, Maria Chiara; Kroemer, Guido

2009-09-01

Autophagy constitutes one of the major responses to stress in eukaryotic cells, and is regulated by a complex network of signaling cascades. Not surprisingly, autophagy is implicated in multiple pathological processes, including infection by pathogens, inflammatory bowel disease, neurodegeneration and cancer. Both oncogenesis and tumor survival are influenced by perturbations of the molecular machinery that controls autophagy. Numerous oncoproteins, including phosphatidylinositol 3-kinase, Akt1 and anti-apoptotic members of the Bcl-2 family suppress autophagy. Conversely, several tumor suppressor proteins (e.g., Atg4c; beclin 1; Bif-1; BH3-only proteins; death-associated protein kinase 1; LKB1/STK11; PTEN; UVRAG) promote the autophagic pathway. This does not entirely apply to p53, one of the most important tumor suppressor proteins, which regulates autophagy in an ambiguous fashion, depending on its subcellular localization. Irrespective of the controversial role of p53, basal levels of autophagy appear to inhibit tumor development. On the contrary, chemotherapy- and metabolic stress-induced activation of the autophagic pathway reportedly contribute to the survival of formed tumors, thereby favoring resistance. In this context, autophagy inhibition would represent a major therapeutic target for chemosensitization. Here, we will review the current knowledge on the dual role of autophagy as an anti- and pro-tumor mechanism.

Mechanisms Underlying the Anti-Aging and Anti-Tumor Effects of Lithocholic Bile Acid

Directory of Open Access Journals (Sweden)

Anthony Arlia-Ciommo

2014-09-01

Full Text Available Bile acids are cholesterol-derived bioactive lipids that play essential roles in the maintenance of a heathy lifespan. These amphipathic molecules with detergent-like properties display numerous beneficial effects on various longevity- and healthspan-promoting processes in evolutionarily distant organisms. Recent studies revealed that lithocholic bile acid not only causes a considerable lifespan extension in yeast, but also exhibits a substantial cytotoxic effect in cultured cancer cells derived from different tissues and organisms. The molecular and cellular mechanisms underlying the robust anti-aging and anti-tumor effects of lithocholic acid have emerged. This review summarizes the current knowledge of these mechanisms, outlines the most important unanswered questions and suggests directions for future research.

Nifedipine, a calcium channel blocker, inhibits advanced glycation end product (AGE)-elicited mesangial cell damage by suppressing AGE receptor (RAGE) expression via peroxisome proliferator-activated receptor-gamma activation

International Nuclear Information System (INIS)

Matsui, Takanori; Yamagishi, Sho-ichi; Takeuchi, Masayoshi; Ueda, Seiji; Fukami, Kei; Okuda, Seiya

2009-01-01

The interaction between advanced glycation end products (AGE) and their receptor RAGE mediates the progressive alteration in renal architecture and loss of renal function in diabetic nephropathy. Oxidative stress generation and inflammation also play a central role in diabetic nephropathy. This study investigated whether and how nifedipine, a calcium channel blocker (CCB), blocked the AGE-elicited mesangial cell damage in vitro. Nifedipine, but not amlodipine, a control CCB, down-regulated RAGE mRNA levels and subsequently reduced reactive oxygen species (ROS) generation in AGE-exposed mesangial cells. AGE increased mRNA levels of vascular cell adhesion molecule-1 (VCAM-1) and induced monocyte chemoattractant protein-1 (MCP-1) production in mesangial cells, both of which were prevented by the treatment with nifedipine, but not amlodipine. The beneficial effects of nifedipine on AGE-exposed mesangial cells were blocked by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ (PPAR-γ). Although nifedipine did not affect expression levels of PPAR-γ, it increased the PPAR-γ transcriptional activity in mesangial cells. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-inflammatory agent against AGE by suppressing RAGE expression in cultured mesangial cells via PPAR-γ activation.

Adrenal scintigraphy with 131I-19-iodocholesterol in the diagnosis of Cushing's syndrome associated with adrenal tumor

International Nuclear Information System (INIS)

Barliev, G.B.

1979-01-01

Seven patients with Cushing's syndrome secondary to adrenocortial tumors were studied using 131 I-19-iodocholesterol. The diagnoses of all cases were verified histologically. In three cases with adenoma the uptake of the tracer was in the tumor only, while the two patients with adrenocortical carcinoma failed to show adrenal accumulation of the labelled compound. In two patients there was a hyperplasia-like scintigraphic pattern, while the stimulation and suppression biochemical tests suggested adrenal tumor. One of these cases was verified as a mixed form (adenoma plus hyperplasia), and the tumor bearing gland was significantly larger on the scan which helped the preoperative localization. In the other case, verified as bilateral multiple adrenocortical adenomas, the autonomus function of both adrenals was proved by dexamethasone suppression scanning. It seems reasonable to use the latter as an adjunctive diagnostic procedure in patients where there is a discrepancy between the standard scintiscan and the biochemical indexes of adrenal hyperfunction. (orig.) 891 MG/orig. 892 MBE [de

Tumors of the pineal region: radiological findings

International Nuclear Information System (INIS)

Roman, G.; Delgado, F.; Cano, A.; Vicente, J.; Ramos, M.

1997-01-01

To consider the different radiological findings that, together with age, sex, clinical picture and serum markers, indicate a presumed or even definitive diagnosis in tumors of the pineal region. We reviewed retrospectively 18 patients diagnosed as having pineal region tumors. The lesions in this series consisted of seven germinoma, three meningiomas, one pineoblastoma. two ependymomas, one teratoma, two glial cysts, and arachnoid cyst and a lipoma. All but the arachnoid cysts and the lipoma were confirmed histologically. We took into account mainly the epidemiological data, tumor markers and CT and MR features. The germinoma was the most common lesions, representing 38.8% of the tumors in our series. All developed in men (mean age: 21 years). Small non tumoral calcifications were present in pineal gland in six of these cases. This tumor usually invades adjacent structures and produces metastatic seeding in CSF. The pineoblastoma contained prominent tumor calcifications. Meningiomas were detected only in middle-aged women. In addition to the fact that the behavior of these lesions was typical of that meningiomas in other locations, meningeal enhancement in the vicinity of the extraaxial tumor aided in the diagnosis. The teratoma showed variable attenuation, ranging from a fatty substance to calcium, and elevated fetoprotein levels. The glial cyst is a cyst lesion that does not be-have exactly like the CSF, while the arachnoid cyst was isointense with respect to the CSF in all sequences. Enhancement was observed in the glial cysts, one peripheral and the other nodular. The assessment of age, sex, clinical picture and tumor markers, together with the features observed in CT an MR images are suggestive of the histological diagnosis of pineal region tumors. We recommend the use of CT because of its availability and its ability detect calcifications, thus indicating a specific histological type, and of MR because of its greater anatomical definition and its, ability to

Effects of low dose mitomycin C on experimental tumor radiotherapy

International Nuclear Information System (INIS)

Yang Jianzheng; Liang Shuo; Qu Yaqin; Pu Chunji; Zhang Haiying; Wu Zhenfeng; Wang Xianli

2001-01-01

Objective: To evaluate the possibility of low dose mitomycin C(MMC) as an adjunct therapy for radiotherapy. Methods: Change in tumor size tumor-bearing mice was measured. Radioimmunoassay was used to determine immune function of mice. Results: Low dose Mac's pretreatment reduced tumor size more markedly than did radiotherapy only. The immune function in mice given with low dose MMC 12h before radiotherapy was obviously higher than that in mice subjected to radiotherapy only (P<0.05), and was close to that in the tumor-bearing mice before radiotherapy. Conclusion: Low dose MMC could improve the radiotherapy effect. Pretreatment with low dose MMC could obviously improve the immune suppression state in mice caused by radiotherapy. The mechanism of its improvement of radiotherapeutic effect by low dose of MMC might be due to its enhancement of immune function and induction of adaptive response in tumor-bearing mice

MicroRNA-22 impairs anti-tumor ability of dendritic cells by targeting p38.

Directory of Open Access Journals (Sweden)

Xue Liang

Full Text Available Dendritic cells (DCs play a critical role in triggering anti-tumor immune responses. Their intracellular p38 signaling is of great importance in controlling DC activity. In this study, we identified microRNA-22 (miR-22 as a microRNA inhibiting p38 protein expression by directly binding to the 3' untranslated region (3'UTR of its mRNA. The p38 down-regulation further interfered with the synthesis of DC-derived IL-6 and the differentiation of DC-driven Th17 cells. Moreover, overexpression of miR-22 in DCs impaired their tumor-suppressing ability while miR-22 inhibitor could reverse this phenomenon and improve the curative effect of DC-based immunotherapy. Thus, our results highlight a suppressive role for miR-22 in the process of DC-invoked anti-tumor immunity and that blocking this microRNA provides a new strategy for generating potent DC vaccines for patients with cancer.

Verification of radiodynamic therapy by medical linear accelerator using a mouse melanoma tumor model.

Science.gov (United States)

Takahashi, Junko; Murakami, Mami; Mori, Takashi; Iwahashi, Hitoshi

2018-02-09

Combined treatment with 5-aminolevulinic acid (5-ALA) and X-rays improves tumor suppression in vivo. This is because the accumulated protoporphyrin IX from 5-ALA enhances the generation of ROS by the X-ray irradiation. In the present study, a high-energy medical linear accelerator was used instead of a non-medical low energy X-ray irradiator, which had been previously used. Tumor-bearing mice implanted with B16-BL6 melanoma cells were treated with fractionated doses of irradiation (in total, 20 or 30 Gy), using two types of X-ray irradiator after 5-ALA administration. Suppression of tumor growth was enhanced with X-ray irradiation in combination with 5-ALA treatment compared with X-ray treatment alone, using both medical and non-medical X-ray irradiators. 5-ALA has been used clinically for photodynamic therapy. Thus, "radiodynamic therapy", using radiation from medical linacs as a physical driving force, rather than the light used in photodynamic therapy, may have potential clinical applications.

Identification of a novel polyprenylated acylphloroglucinol‑derived SIRT1 inhibitor with cancer‑specific anti-proliferative and invasion-suppressing activities.

Science.gov (United States)

Zhu, Lijia; Qi, Ji; Chiao, Christine Ya-Chi; Zhang, Qiang; Porco, John A; Faller, Douglas V; Dai, Yan

2014-11-01

SIRT1, a class III histone deacetylase, plays a critical role in regulating cancer cell growth, migration and invasion, which makes it a potential target for cancer therapeutics. In this study, we screened derivatives of several groups of natural products and identified a novel SIRT1 inhibitor JQ-101, a synthetic derivative of the polyprenylated acylphloroglucinol (PPAP) natural products, with an IC(50) for SIRT1 of 30 µM in vitro, with 5-fold higher activity for SIRT1 vs. SIRT2. Exposure of tumor cells to JQ-101 significantly enhanced acetylation of p53 and histone H4K16 at known sites of SIRT1 deacetylation, validating SIRT1 as its cellular target. JQ-101 suppressed cancer cell growth and survival by targeting SIRT1, and also exhibited selective cytotoxicity towards a panel of human tumor cell lines, while producing no toxicity in two normal human cell types at comparable concentrations. JQ-101 induced both apoptosis and cell senescence, and suppressed cancer cell invasion in vitro. In summary, we have identified JQ-101 as a new SIRT1 inhibitor which may have potential application in cancer treatment through its ability to induce tumor cell apoptosis and senescence and suppress cancer cell invasion.

Identification of a novel polyprenylated acylphloroglucinol-derived SIRT1 inhibitor with cancer-specific anti-proliferative and invasion-suppressing activities

Science.gov (United States)

ZHU, LIJIA; QI, JI; CHIAO, CHRISTINE YA-CHI; ZHANG, QIANG; PORCO, JOHN A.; FALLER, DOUGLAS V.; DAI, YAN

2014-01-01

SIRT1, a class III histone deacetylase, plays a critical role in regulating cancer cell growth, migration and invasion, which makes it a potential target for cancer therapeutics. In this study, we screened derivatives of several groups of natural products and identified a novel SIRT1 inhibitor JQ-101, a synthetic derivative of the polyprenylated acylphloroglucinol (PPAP) natural products, with an IC50 for SIRT1 of 30 μM in vitro, with 5-fold higher activity for SIRT1 vs. SIRT2. Exposure of tumor cells to JQ-101 significantly enhanced acetylation of p53 and histone H4K16 at known sites of SIRT1 deacetylation, validating SIRT1 as its cellular target. JQ-101 suppressed cancer cell growth and survival by targeting SIRT1, and also exhibited selective cytotoxicity towards a panel of human tumor cell lines, while producing no toxicity in two normal human cell types at comparable concentrations. JQ-101 induced both apoptosis and cell senescence, and suppressed cancer cell invasion in vitro. In summary, we have identified JQ-101 as a new SIRT1 inhibitor which may have potential application in cancer treatment through its ability to induce tumor cell apoptosis and senescence and suppress cancer cell invasion. PMID:25189993

Folic acid-decorated polyamidoamine dendrimer exhibits high tumor uptake and sustained highly localized retention in solid tumors: Its utility for local siRNA delivery.

Science.gov (United States)

Xu, Leyuan; Yeudall, W Andrew; Yang, Hu

2017-07-15

-targeted PAMAM dendrimer G4 complexed with siVEGFA resulted in pronounced tumor suppression in an HN12 xenograft tumor model. Tumor suppression was attributed to enhanced tumor uptake of siRNA and prolonged nanoparticle retention in the tumor. Taken together, G4-FA shows high tumor uptake and sustained highly localized retention properties, making it a suitable platform for local delivery of siRNAs to treat cancers that are readily accessible such as HNSCC. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Manic fringe inhibits tumor growth by suppressing Notch3 degradation in lung cancer.

Science.gov (United States)

Yi, Fuming; Amarasinghe, Baru; Dang, Thao P

2013-01-01

Notch signaling plays an essential role in development as well as cancer. We have previously shown that Notch3 is important for lung cancer growth and survival. Notch receptors are activated through the interaction with their ligands, resulting in proteolytic cleavage of the receptors. This interaction is modulated by Fringe, a family of fucose-specific β1,3 N-acetylglucosaminyltransferases that modify the extracellular subunit of Notch receptors. Studies in developmental models showed that Fringe enhances Notch's response to Delta ligands at the expense of Jagged ligands. We observed that Manic Fringe expression is down-regulated in lung cancer. Since Jagged1, a known ligand for Notch3, is often over-expressed in lung cancer, we hypothesized that Fringe negatively regulates Notch3 activation. In this study, we show that re-expression of Manic Fringe down-regulates Notch3 target genes HES1 and HeyL and reduces tumor phenotype in vitro and in vivo. The mechanism for this phenomenon appears to be related to modulation of Notch3 protein stability. Proteasome inhibition reverses Manic Fringe-induced protein turnover. Taken together, our data provide the first evidence that Manic Fringe functions as a tumor suppressor in the lung and that the mechanism of its anti-tumor activity is mediated by inhibition of Notch3 activation.

Pyrvinium targets the unfolded protein response to hypoglycemia and its anti-tumor activity is enhanced by combination therapy.