Pathophysiological aspects and therapeutic approaches of tumoral osteolysis and hypercalcemia.

Science.gov (United States)

Bonjour, J P; Rizzoli, R

1989-01-01

Malignant tumors can affect the integrity of the skeletal tissue and the homeostasis of the two main components of bone mineral, calcium (Ca) and inorganic phosphate (Pi). Various tumoral cell products can increase bone resorption by influencing the number of osteoclasts and/or their activity. These tumoral products could act either directly on bone cells of the osteoblastic or osteoclastic lineages, or indirectly by influencing cells secreting osteotropic factors, such as interleukin-1, tumor necrosis factors, transforming growth factors, and colony-stimulating factor. Among the classical calciotropic hormones, 1,25-dihydroxyvitamin D3 could be implicated in lymphoma. In hypercalcemia of malignancy, an increase in bone resorption is observed in most patients. However, in many cases an increased tubular reabsorption of Ca has been documented as well. This phenomenon when present after adequate rehydration is probably due to the secretion by the tumoral cells of a parathyroid hormone-related peptide (PTHrP). This factor has been recently identified as a protein containing 141 amino acids. This protein or some very close analogs have been shown to be secreted by lung, kidney and also breast carcinoma. Besides increasing bone resorption and stimulating tubular reabsorption of Ca, PTHrP also selectively decreases the tubular reabsorption of Pi, an action that may explain the hypophosphatemia observed in some types of neoplasm. Therapeutically, administration of antiresorbing agents such as clodronate or other bisphosphonates can normalize the increased osteolysis and, if present, the associated elevation in the plasma level of Ca in most cancer patients. However in some cases, wherein the prevailing hypercalcemic mechanism is due to an enhancement in the tubular reabsorption of Ca, other therapeutic means should be associated with the antiosteolytic bisphosphonate therapy.

The in vivo therapeutic efficacy of the oncolytic adenovirus Delta24-RGD is mediated by tumor-specific immunity.

Directory of Open Access Journals (Sweden)

Anne Kleijn

Full Text Available The oncolytic adenovirus Delta24-RGD represents a new promising therapeutic agent for patients with a malignant glioma and is currently under investigation in clinical phase I/II trials. Earlier preclinical studies showed that Delta24-RGD is able to effectively lyse tumor cells, yielding promising results in various immune-deficient glioma models. However, the role of the immune response in oncolytic adenovirus therapy for glioma has never been explored. To this end, we assessed Delta24-RGD treatment in an immune-competent orthotopic mouse model for glioma and evaluated immune responses against tumor and virus. Delta24-RGD treatment led to long-term survival in 50% of mice and this effect was completely lost upon administration of the immunosuppressive agent dexamethasone. Delta24-RGD enhanced intra-tumoral infiltration of F4/80+ macrophages, CD4+ and CD8+ T-cells, and increased the local production of pro-inflammatory cytokines and chemokines. In treated mice, T cell responses were directed to the virus as well as to the tumor cells, which was reflected in the presence of protective immunological memory in mice that underwent tumor rechallenge. Together, these data provide evidence that the immune system plays a vital role in the therapeutic efficacy of oncolytic adenovirus therapy of glioma, and may provide angles to future improvements on Delta24-RGD therapy.

A virtual therapeutic environment with user projective agents.

Science.gov (United States)

Ookita, S Y; Tokuda, H

2001-02-01

Today, we see the Internet as more than just an information infrastructure, but a socializing place and a safe outlet of inner feelings. Many personalities develop aside from real world life due to its anonymous environment. Virtual world interactions are bringing about new psychological illnesses ranging from netaddiction to technostress, as well as online personality disorders and conflicts in multiple identities that exist in the virtual world. Presently, there are no standard therapy models for the virtual environment. There are very few therapeutic environments, or tools especially made for virtual therapeutic environments. The goal of our research is to provide the therapy model and middleware tools for psychologists to use in virtual therapeutic environments. We propose the Cyber Therapy Model, and Projective Agents, a tool used in the therapeutic environment. To evaluate the effectiveness of the tool, we created a prototype system, called the Virtual Group Counseling System, which is a therapeutic environment that allows the user to participate in group counseling through the eyes of their Projective Agent. Projective Agents inherit the user's personality traits. During the virtual group counseling, the user's Projective Agent interacts and collaborates to recover and increase their psychological growth. The prototype system provides a simulation environment where psychologists can adjust the parameters and customize their own simulation environment. The model and tool is a first attempt toward simulating online personalities that may exist only online, and provide data for observation.

Therapeutic response assessment of percutaneous radiofrequency ablation for hepatocellular carcinoma: Utility of contrast-enhanced agent detection imaging

International Nuclear Information System (INIS)

Kim, Chan Kyo; Choi, Dongil; Lim, Hyo K.; Kim, Seung Hoon; Lee, Won Jae; Kim, Min Ju; Lee, Ji Yeon; Jeon, Yong Hwan; Lee, Jongmee; Lee, Soon Jin; Lim, Jae Hoon

2005-01-01

Purpose: To assess the utility of contrast-enhanced agent detection imaging (ADI) in the assessment of the therapeutic response to percutaneous radiofrequency (RF) ablation in patients with hepatocellular carcinoma (HCC). Materials and methods: Ninety patients with a total of 97 nodular HCCs (mean, 2.1 ± 1.3 cm; range, 1.0-5.0 cm) treated with percutaneous RF ablation under the ultrasound guidance were evaluated with contrast-enhanced ADI after receiving an intravenous bolus injection of a microbubble contrast agent (SH U 508A). We obtained serial contrast-enhanced ADI images during the time period from 15 to 90 s after the initiation of the bolus contrast injection. All of the patients underwent a follow-up four-phase helical CT at 1 month after RF ablation, which was then repeated at 2-4 month intervals during a period of at least 12 months. The results of the contrast-enhanced ADI were compared with those of the follow-up CT in terms of the presence or absence of residual unablated tumor and local tumor progression in the treated lesions. Results: On contrast-enhanced ADI, technical success was obtained in 94 (97%) of the 97 HCCs, while residual unablated tumors were found in three HCCs (3%). Two of the three tumors that were suspicious (was not proven) for incomplete ablation were subjected to additional RF ablation. The remaining one enhancing lesion that was suspicious of a residual tumor on contrast-enhanced ADI was revealed to be reactive hyperemia at the 1-month follow-up CT. Therefore; the diagnostic concordance between the contrast-enhanced ADI and 1-month follow-up CT was 99%. Of the 94 ablated HCCs without residual tumors on both the contrast-enhanced ADI and 1-month follow-up CT after the initial RF ablation, five (5%) had CT findings of local tumor progression at a subsequent follow-up CT. Conclusion: Despite its limitations in predicting local tumor progression in the treated tumors, contrast-enhanced ADI is potentially useful for evaluating the

Development of Class IIa Bacteriocins as Therapeutic Agents

Directory of Open Access Journals (Sweden)

Christopher T. Lohans

2012-01-01

Full Text Available Class IIa bacteriocins have been primarily explored as natural food preservatives, but there is much interest in exploring the application of these peptides as therapeutic antimicrobial agents. Bacteriocins of this class possess antimicrobial activity against several important human pathogens. Therefore, the therapeutic development of these bacteriocins will be reviewed. Biological and chemical modifications to both stabilize and increase the potency of bacteriocins are discussed, as well as the optimization of their production and purification. The suitability of bacteriocins as pharmaceuticals is explored through determinations of cytotoxicity, effects on the natural microbiota, and in vivo efficacy in mouse models. Recent results suggest that class IIa bacteriocins show promise as a class of therapeutic agents.

New Therapeutic Agent against Arterial Thrombosis: An Iridium(III-Derived Organometallic Compound

Directory of Open Access Journals (Sweden)

Chih-Wei Hsia

2017-12-01

Full Text Available Platelet activation plays a major role in cardio and cerebrovascular diseases, and cancer progression. Disruption of platelet activation represents an attractive therapeutic target for reducing the bidirectional cross talk between platelets and tumor cells. Platinum (Pt compounds have been used for treating cancer. Hence, replacing Pt with iridium (Ir is considered a potential alternative. We recently developed an Ir(III-derived complex, [Ir(Cp*1-(2-pyridyl-3-(2-hydroxyphenylimidazo[1,5-a]pyridine Cl]BF4 (Ir-11, which exhibited strong antiplatelet activity; hence, we assessed the therapeutic potential of Ir-11 against arterial thrombosis. In collagen-activated platelets, Ir-11 inhibited platelet aggregation, adenosine triphosphate (ATP release, intracellular Ca2+ mobilization, P-selectin expression, and OH· formation, as well as the phosphorylation of phospholipase Cγ2 (PLCγ2, protein kinase C (PKC, mitogen-activated protein kinases (MAPKs, and Akt. Neither the adenylate cyclase inhibitor nor the guanylate cyclase inhibitor reversed the Ir-11-mediated antiplatelet effects. In experimental mice, Ir-11 prolonged the bleeding time and reduced mortality associated with acute pulmonary thromboembolism. Ir-11 plays a crucial role by inhibiting platelet activation through the inhibition of the PLCγ2–PKC cascade, and the subsequent suppression of Akt and MAPK activation, ultimately inhibiting platelet aggregation. Therefore, Ir-11 can be considered a new therapeutic agent against either arterial thrombosis or the bidirectional cross talk between platelets and tumor cells.

Evaluation of 188Re-labeled PEGylated nanoliposome as a radionuclide therapeutic agent in an orthotopic glioma-bearing rat model

Directory of Open Access Journals (Sweden)

Huang FYJ

2015-01-01

Full Text Available Feng-Yun J Huang,1 Te-Wei Lee,2 Chih-Hsien Chang,2 Liang-Cheng Chen,2 Wei-Hsin Hsu,2 Chien-Wen Chang,1 Jem-Mau Lo1 1Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan; 2Institute of Nuclear Energy Research, Longtan, Taiwan Purpose: In this study, the 188Re-labeled PEGylated nanoliposome (188Re-liposome was prepared and evaluated as a therapeutic agent for glioma.Materials and methods: The reporter cell line, F98luc was prepared via Lentivector expression kit system and used to set up the orthotopic glioma-bearing rat model for non-invasive bioluminescent imaging. The maximum tolerated dose applicable in Fischer344 rats was explored via body weight monitoring of the rats after single intravenous injection of 188Re-liposome with varying dosages before the treatment study. The OLINDA/EXM 1.1 software was utilized for estimating the radiation dosimetry. To assess the therapeutic efficacy, tumor-bearing rats were intravenously administered 188Re-liposome or normal saline followed by monitoring of the tumor growth and animal survival time. In addition, the histopathological examinations of tumors were conducted on the 188Re-liposome-treated rats.Results: By using bioluminescent imaging, the well-established reporter cell line (F98luc showed a high relationship between cell number and its bioluminescent intensity (R2=0.99 in vitro; furthermore, it could also provide clear tumor imaging for monitoring tumor growth in vivo. The maximum tolerated dose of 188Re-liposome in Fischer344 rats was estimated to be 333 MBq. According to the dosimetry results, higher equivalent doses were observed in spleen and kidneys while very less were in normal brain, red marrow, and thyroid. For therapeutic efficacy study, the progression of tumor growth in terms of tumor volume and/or tumor weight was significantly slower for the 188Re-liposome-treated group than the control group (P<0.05. As a result, the

Early quantification of the therapeutic efficacy of the vascular disrupting agent, CKD-516, using dynamic contrast-enhanced ultrasonography in rabbit VX2 liver tumors

Energy Technology Data Exchange (ETDEWEB)

Joo, Ijin; Kim, Jung Hoon; Lee, Jeong Min; Choi, Jin Woo; Han, Joon Koo; Choi, Byung Ihn [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of)

2014-03-15

To evaluate the usefulness of dynamic contrast-enhanced ultrasonography (DCE-US) in the early quantification of hemodynamic change following administration of the vascular disrupting agent (VDA) CKD-516 using a rabbit VX2 liver tumor model. This study was approved by our institutional animal care and use committee. Eight VX2 liver-tumor-bearing rabbits were treated with intravenous CKD-516, and all underwent DCE-US using SonoVue before and again 2, 4, 6, and 24 hours following their treatment. The tumor perfusion parameters were obtained from the time-intensity curve of the DCE-US data. Repeated measures analysis of variance was performed to assess any significant change in tumor perfusion over time. Relative changes in the DCE-US parameters between the baseline and follow-up assessments were correlated with the relative changes in tumor size over the course of seven days using Pearson correlation. CKD-516 treatment resulted in significant changes in the DCE-US parameters, including the peak intensity, total area under the time-intensity curve (AUCtotal), and AUC during wash-out (AUCout) over time (P<0.05). Pairwise comparison tests revealed that the AUCtotal and AUC during wash-in (AUCin) seen on the two-hour follow-up were significantly lower than the baseline values (P<0.05). However, none of early changes in the DCE-US parameters until 24-hour follow-up showed a significant correlation with the relative changes in tumor size during seven days after CKD-516 treatment. Our results suggest that a novel VDA (CKD-516) can cause disruption of tumor perfusion as early as two hours after treatment and that the therapeutic effect of CKD-516 treatment can be effectively quantified using DCE-US.

Enhanced Delivery of Gold Nanoparticles with Therapeutic Potential for Targeting Human Brain Tumors

Science.gov (United States)

Etame, Arnold B.

The blood brain barrier (BBB) remains a major challenge to the advancement and application of systemic anti-cancer therapeutics into the central nervous system. The structural and physiological delivery constraints of the BBB significantly limit the effectiveness of conventional chemotherapy, thereby making systemic administration a non-viable option for the vast majority of chemotherapy agents. Furthermore, the lack of specificity of conventional systemic chemotherapy when applied towards malignant brain tumors remains a major shortcoming. Hence novel therapeutic strategies that focus both on targeted and enhanced delivery across the BBB are warranted. In recent years nanoparticles (NPs) have emerged as attractive vehicles for efficient delivery of targeted anti-cancer therapeutics. In particular, gold nanoparticles (AuNPs) have gained prominence in several targeting applications involving systemic cancers. Their enhanced permeation and retention within permissive tumor microvasculature provide a selective advantage for targeting. Malignant brain tumors also exhibit transport-permissive microvasculature secondary to blood brain barrier disruption. Hence AuNPs may have potential relevance for brain tumor targeting. However, the permeation of AuNPs across the BBB has not been well characterized, and hence is a potential limitation for successful application of AuNP-based therapeutics within the central nervous system (CNS). In this dissertation, we designed and characterized AuNPs and assessed the role of polyethylene glycol (PEG) on the physical and biological properties of AuNPs. We established a size-dependent permeation profile with respect to core size as well as PEG length when AuNPs were assessed through a transport-permissive in-vitro BBB. This study was the first of its kind to systematically examine the influence of design on permeation of AuNPs through transport-permissive BBB. Given the significant delivery limitations through the non

Current progress and future perspectives in the development of anti-polo-like kinase 1 therapeutic agents [version 1; referees: 4 approved

Directory of Open Access Journals (Sweden)

Jung-Eun Park

2017-06-01

Full Text Available Although significant levels of side effects are often associated with their use, microtubule-directed agents that primarily target fast-growing mitotic cells have been considered to be some of the most effective anti-cancer therapeutics. With the hope of developing new-generation anti-mitotic agents with reduced side effects and enhanced tumor specificity, researchers have targeted various proteins whose functions are critically required for mitotic progression. As one of the highly attractive mitotic targets, polo-like kinase 1 (Plk1 has been the subject of an extensive effort for anti-cancer drug discovery. To date, a variety of anti-Plk1 agents have been developed, and several of them are presently in clinical trials. Here, we will discuss the current status of generating anti-Plk1 agents as well as future strategies for designing and developing more efficacious anti-Plk1 therapeutics.

Targeting tissue factor as a novel therapeutic oncotarget for eradication of cancer stem cells isolated from tumor cell lines, tumor xenografts and patients of breast, lung and ovarian cancer.

Science.gov (United States)

Hu, Zhiwei; Xu, Jie; Cheng, Jijun; McMichael, Elizabeth; Yu, Lianbo; Carson, William E

2017-01-03

Targeting cancer stem cell (CSC) represents a promising therapeutic approach as it can potentially fight cancer at its root. The challenge is to identify a surface therapeutic oncotarget on CSC. Tissue factor (TF) is known as a common yet specific surface target for cancer cells and tumor neovasculature in several solid cancers. However, it is unknown if TF is expressed by CSCs. Here we demonstrate that TF is constitutively expressed on CD133 positive (CD133+) or CD24-CD44+ CSCs isolated from human cancer cell lines, tumor xenografts from mice and breast tumor tissues from patients. TF-targeted agents, i.e., a factor VII (fVII)-conjugated photosensitizer (fVII-PS for targeted photodynamic therapy) and fVII-IgG1Fc (Immunoconjugate or ICON for immunotherapy), can eradicate CSC via the induction of apoptosis and necrosis and via antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity, respectively. In conclusion, these results demonstrate that TF is a novel surface therapeutic oncotarget for CSC, in addition to cancer cell TF and tumor angiogenic vascular endothelial TF. Moreover, this research highlights that TF-targeting therapeutics can effectively eradicate CSCs, without drug resistance, isolated from breast, lung and ovarian cancer with potential to translate into other most commonly diagnosed solid cancer, in which TF is also highly expressed.

Folic acid tagged nanoceria as a novel therapeutic agent in ovarian cancer

International Nuclear Information System (INIS)

Hijaz, Miriana; Das, Soumen; Mert, Ismail; Gupta, Ankur; Al-Wahab, Zaid; Tebbe, Calvin; Dar, Sajad; Chhina, Jasdeep; Giri, Shailendra; Munkarah, Adnan; Seal, Sudipta; Rattan, Ramandeep

2016-01-01

Nanomedicine is a very promising field and nanomedical drugs have recently been used as therapeutic agents against cancer. In a previous study, we showed that Nanoceria (NCe), nanoparticles of cerium oxide, significantly inhibited production of reactive oxygen species, cell migration and invasion of ovarian cancer cells in vitro, without affecting cell proliferation and significantly reduced tumor growth in an ovarian cancer xenograft nude model. Increased expression of folate receptor-α, an isoform of membrane-bound folate receptors, has been described in ovarian cancer. To enable NCe to specifically target ovarian cancer cells, we conjugated nanoceria to folic acid (NCe-FA). Our aim was to investigate the pre-clinical efficacy of NCe-FA alone and in combination with Cisplatin. Ovarian cancer cell lines were treated with NCe or NCe-FA. Cell viability was assessed by MTT and colony forming units. In vivo studies were carried in A2780 generated mouse xenografts treated with 0.1 mg/Kg NCe, 0.1 mg/Kg; NCe-FA and cisplatinum, 4 mg/Kg by intra-peritoneal injections. Tumor weights and burden scores were determined. Immunohistochemistry and toxicity assays were used to evaluate treatment effects. We show that folic acid conjugation of NCe increased the cellular NCe internalization and inhibited cell proliferation. Mice treated with NCe-FA had a lower tumor burden compared to NCe, without any vital organ toxicity. Combination of NCe-FA with cisplatinum decreased the tumor burden more significantly. Moreover, NCe-FA was also effective in reducing proliferation and angiogenesis in the xenograft mouse model. Thus, specific targeting of ovarian cancer cells by NCe-FA holds great potential as an effective therapeutic alone or in combination with standard chemotherapy. The online version of this article (doi:10.1186/s12885-016-2206-4) contains supplementary material, which is available to authorized users

Disrupting established tumor blood vessels: an emerging therapeutic strategy for cancer.

Science.gov (United States)

McKeage, Mark J; Baguley, Bruce C

2010-04-15

The unique characteristics of tumor vasculature represent an attractive target that may be exploited by vascular-targeting anticancer agents. A promising strategy involves the selective disruption of established tumor blood vessels by tumor-vascular disrupting agents (tumor-VDAs), which exhibit antivascular activity, resulting in inhibition of tumor blood flow and extensive necrosis within the tumor core. The tumor-VDA class can be subdivided into flavonoid compounds, which are related to flavone acetic acid, and tubulin-binding compounds. ASA404, of the flavonoid class, is the most advanced tumor-VDA in clinical development and has been evaluated preclinically and in several phase 1 and phase 2 studies. Preclinical studies have demonstrated the selective apoptosis of tumor endothelial cells and the inhibition of tumor blood flow. Synergistic activity was observed with ASA404 and with several chemotherapeutic agents, particularly taxanes. In clinical trials, compared with chemotherapy alone, ASA404 was tolerated well and produced improved activity in patients with nonsmall cell lung cancer when combined with paclitaxel and carboplatin. Phase 3 clinical trials are ongoing. Selectively targeting established tumor vasculature with tumor-VDAs represents a promising and innovative approach to improving the efficacy of standard anticancer therapies. (c) 2010 American Cancer Society.

Multifunctional Nanoparticles for Brain Tumor Diagnosis and Therapy

Science.gov (United States)

Cheng, Yu; Morshed, Ramin; Auffinger, Brenda; Tobias, Alex L.; Lesniak, Maciej S.

2013-01-01

Brain tumors are a diverse group of neoplasms that often carry a poor prognosis for patients. Despite tremendous efforts to develop diagnostic tools and therapeutic avenues, the treatment of brain tumors remains a formidable challenge in the field of neuro-oncology. Physiological barriers including the blood-brain barrier result in insufficient accumulation of therapeutic agents at the site of a tumor, preventing adequate destruction of malignant cells. Furthermore, there is a need for improvements in brain tumor imaging to allow for better characterization and delineation of tumors, visualization of malignant tissue during surgery, and tracking of response to chemotherapy and radiotherapy. Multifunctional nanoparticles offer the potential to improve upon many of these issues and may lead to breakthroughs in brain tumor management. In this review, we discuss the diagnostic and therapeutic applications of nanoparticles for brain tumors with an emphasis on innovative approaches in tumor targeting, tumor imaging, and therapeutic agent delivery. Clinically feasible nanoparticle administration strategies for brain tumor patients are also examined. Furthermore, we address the barriers towards clinical implementation of multifunctional nanoparticles in the context of brain tumor management. PMID:24060923

Enhancement of 67Ga tumor-to-blood ratios by chelating agent

International Nuclear Information System (INIS)

Saji, Hideo; Yokoyama, Akira; Hata, Naotaka; Misaki, Atsushi; Tanaka, Hisashi.

1980-01-01

Chelating agent, such as, CaEDTA, CaDTPA, D-penicillamine, DMSA, desferoxamine, NTA, cysteine ethyl ester, BAL, α-MPG, phthalein complexone, were tested as a possible contrast enhancing agent for tumor imaging with 67 Ga-citrate. The intravenous administration of a chelating agent to Ehrlich's tumor bearing mice, one hour after the injection of 67 Ga-citrate, accelerated the blood clearance with only a very slight change of activity in the target, increasing the tumor-to-blood ratio, and consequently achieving a better visualization. Among the tested chelating agents, D-penicillamine showed the highest target-to-nontarget ratio at a shorter time: a good tumor-to-blood ratio, performed after 24 hr with non-treated animals, was achieved in only 1-3 hr with post-treated animals. Thus, D-penicillamine hold a considerable promise as a contrast enhancing agent for future clinical use. (author)

Acute Organophosphate Poisonings: Therapeutic Dilemmas and New Potential Therapeutic Agents

International Nuclear Information System (INIS)

Vucinic, S.; Jovanovic, D.; Vucinic, Z.; Todorovic, V.; Segrt, Z.

2007-01-01

It has been six decades since synthesis of organophosphates, but this chapter has not yet come to a closure. Toxic effects of organophosphates are well known and the current therapeutic scheme includes supportive therapy and antidotes. There is a dilemma on whether and when to apply gastric lavage and activated charcoal. According to Position Statement (by EAPCCT) it should be applied only if the patient presents within one hour of ingestion, with potentially lethal ingested dose. Atropine, a competitive antagonist of acetylcholine at m-receptors, which antagonizes bronchosecretion and bronchoconstriction, is the corner stone of acute organophosphate poisoning therapy. There were many attempts to find a more efficient drug, including glycopyrrolate which has been used even in clinical trials, but it still can not replace atropine. The only dilemma about atropine usage which still exists, concerns usage of high atropine dose and scheme of application. The most efficient atropinization is achieved with bolus doses of 1-2mg of atropine i.v push, with repeating the dose on each 5 minutes until signs of atropinization are registered. Diazepam, with its GABA stabilizing effect, reduces central nervous system damage and central respiratory weakness. Oximes reactivate phosphorylated acetylcholinesterase, which still has not gone ageing, reducing acetylcholine concentration and cholinergic crisis. These effects are clearly demonstrated in experimental conditions, but the clinical significance of oximes is still unclear and there are still those who question oxime therapy. For those who approve it, oxime dosage, duration of therapy, the choice of oxime for certain OP is still an open issue. We need new, more efficient antidotes, and those that are in use are only the small part of the therapy which could be used. Experimental studies show favorable therapeutic effect of many agents, but none of them has been introduced in standard treatment of OPI poisoning in the last 30

Biodegradable Drug-Loaded Hydroxyapatite Nanotherapeutic Agent for Targeted Drug Release in Tumors.

Science.gov (United States)

Sun, Wen; Fan, Jiangli; Wang, Suzhen; Kang, Yao; Du, Jianjun; Peng, Xiaojun

2018-03-07

Tumor-targeted drug delivery systems have been increasingly used to improve the therapeutic efficiency of anticancer drugs and reduce their toxic side effects in vivo. Focused on this point, doxorubicin (DOX)-loaded hydroxyapatite (HAP) nanorods consisting of folic acid (FA) modification (DOX@HAP-FA) were developed for efficient antitumor treatment. The DOX-loaded nanorods were synthesized through in situ coprecipitation and hydrothermal method with a DOX template, demonstrating a new procedure for drug loading in HAP materials. DOX could be efficiently released from DOX@HAP-FA within 24 h in weakly acidic buffer solution (pH = 6.0) because of the degradation of HAP nanorods. With endocytosis under the mediation of folate receptors, the nanorods exhibited enhanced cellular uptake and further degraded, and consequently, the proliferation of targeted cells was inhibited. More importantly, in a tumor-bearing mouse model, DOX@HAP-FA treatment demonstrated excellent tumor growth inhibition. In addition, no apparent side effects were observed during the treatment. These results suggested that DOX@HAP-FA may be a promising nanotherapeutic agent for effective cancer treatment in vivo.

The non-classical antigens of HLA-G and HLA-E as diagnostic and prognostic biomarkers and as therapeutic targets in transplantation and tumors.

Science.gov (United States)

Seliger, Barbara

2013-01-01

The non-classical human leukocyte antigen (HLA) class I antigen HLA-G represents a tolerogenic molecule and is involved in the inhibition of natural killer cell and cytotoxic T lymphocyte-mediated cytotoxicity. Under physiological conditions, HLA-G expression is mainly restricted to immune-privileged tissues, whereas it is overexpressed in tumors and transplants as well as in virus-infected cells. Due to its immunosuppressive features, HLA-G is important for pregnancy or organ transplantation and autoimmune diseases as well as cancer immune escape. This review focusses on the expression, regulation, and function of HLA-G in tumor cells andlor in transplants as well as therapeutic tools for enhancing (transplantation) or avoiding (tumor) tolerance. Thus, HLA-G or HLA-G-derived synthetic molecules might be used as therapeutic agents in combination with immunosuppressive drugs to enhance organ tolerance upon transplantation. In addition, HLA-G neoexpressing tumor cells could be targeted by HLA-G-specific microRNAs in order to enhance tumor immunogenicity.

Preclinical therapeutic potential of a nitrosylating agent in the treatment of ovarian cancer.

Directory of Open Access Journals (Sweden)

Shailendra Giri

Full Text Available This study examines the role of s-nitrosylation in the growth of ovarian cancer using cell culture based and in vivo approaches. Using the nitrosylating agent, S-nitrosoglutathione (GSNO, a physiological nitric oxide molecule, we show that GSNO treatment inhibited proliferation of chemoresponsive and chemoresistant ovarian cancer cell lines (A2780, C200, SKVO3, ID8, OVCAR3, OVCAR4, OVCAR5, OVCAR7, OVCAR8, OVCAR10, PE01 and PE04 in a dose dependent manner. GSNO treatment abrogated growth factor (HB-EGF induced signal transduction including phosphorylation of Akt, p42/44 and STAT3, which are known to play critical roles in ovarian cancer growth and progression. To examine the therapeutic potential of GSNO in vivo, nude mice bearing intra-peritoneal xenografts of human A2780 ovarian carcinoma cell line (2 × 10(6 were orally administered GSNO at the dose of 1 mg/kg body weight. Daily oral administration of GSNO significantly attenuated tumor mass (p<0.001 in the peritoneal cavity compared to vehicle (phosphate buffered saline treated group at 4 weeks. GSNO also potentiated cisplatin mediated tumor toxicity in an A2780 ovarian carcinoma nude mouse model. GSNO's nitrosylating ability was reflected in the induced nitrosylation of various known proteins including NFκB p65, Akt and EGFR. As a novel finding, we observed that GSNO also induced nitrosylation with inverse relationship at tyrosine 705 phosphorylation of STAT3, an established player in chemoresistance and cell proliferation in ovarian cancer and in cancer in general. Overall, our study underlines the significance of S-nitrosylation of key cancer promoting proteins in modulating ovarian cancer and proposes the therapeutic potential of nitrosylating agents (like GSNO for the treatment of ovarian cancer alone or in combination with chemotherapeutic drugs.

Development of Class IIa Bacteriocins as Therapeutic Agents

OpenAIRE

Christopher T. Lohans; John C. Vederas

2012-01-01

Class IIa bacteriocins have been primarily explored as natural food preservatives, but there is much interest in exploring the application of these peptides as therapeutic antimicrobial agents. Bacteriocins of this class possess antimicrobial activity against several important human pathogens. Therefore, the therapeutic development of these bacteriocins will be reviewed. Biological and chemical modifications to both stabilize and increase the potency of bacteriocins are discussed, as well as ...

Evaluation of technetium-99M labeled RGD-containing peptide as potential tumor imaging agents in tumor-bearing mice

International Nuclear Information System (INIS)

Hu Silong; Zeng Jun; Zhang Lihua

2004-01-01

Integrins (especially α v β 3 ) play a important role in angiogenesis, growth and metastasis of a solid tumor. Targeting tumor with radiolabeled ligands of the α V β 3 integrin may provide information about the receptor status and enable specific therapeutic strategy. A tripeptidic sequence Arg-Gly-Asp (RGD) is often the primary site of recognition by integrins. The aim of this study examine 99m Tc-labeled elevenfold peptide (GRGDSRGDSCY, GY11) that target the α V β 3 integrin to determine if this agent target tumors for diagnostic imaging and/or targeted radiotherapy of cancer. Methods: GY11 was radiolabelled with 99 Tc m via cystine residue by means of stannous chloride. 99 Tc m -GY11 was injected through tail vein into nude mice bearing A375 human melanoma. Biodistribution was investigated at 1,2,4 and 6 hours after injection. Percentage injected dose/gram of tissue (%ID/g) and tumor/non-tumor ratios were calculated. Planar images were acquired with SPECT at 1,2,4,6hrs, respectively. Results: 99 Tc m -GY11 was rapidly cleared from blood and excreted predominantly from the kidney. Tumor uptake at 2h postinjection was 3.1%ID/g. The ratios of tumor/blood and tumor/muscle increased from 0.9-6.2, 4.3-13.5 from 1-6hrs postinjection, respectively. Planar images confirmed that tumor could be visualized at 4h after administration of 99 Tc m -GY11. Conclusion: The results suggest that 99 Tc m -GY11 is a promising compound for noninvasive determining the α V β 3 integrin status. 99 Tc m -GY11 SPECT may be useful to imaging α V β 3 -positive tumor and also guide proper utility of α V β 3 antagonist therapy and radionuclide therapy for cancer. (authors)

Tumor Microenvironment Gene Signature as a Prognostic Classifier and Therapeutic Target

Science.gov (United States)

2016-06-01

AWARD NUMBER: W81XWH-14-1-0107 TITLE: Tumor Microenvironment Gene Signature as a Prognostic Classifier and Therapeutic Target PRINCIPAL...AND SUBTITLE Tumor Microenvironment Gene Signature as a 5a. CONTRACT NUMBER W81XWH-14-1-0107 Prognostic Classifier and Therapeutic Target 5b...gene signature that correlates with poor survival in ovarian cancer patients. We are refining this gene signature to develop biomarkers for the

Therapeutic journery of nitrogen mustard as alkylating anticancer agents: Historic to future perspectives.

Science.gov (United States)

Singh, Rajesh K; Kumar, Sahil; Prasad, D N; Bhardwaj, T R

2018-05-10

Cancer is considered as one of the most serious health problems today. The discovery of nitrogen mustard as an alkylating agent in 1942, opened a new era in the cancer chemotherapy. This valuable class of alkylating agent exerts its biological activity by binding to DNA, cross linking two strands, preventing DNA replication and ultimate cell death. At the molecular level, nitrogen lone pairs of nitrogen mustard generate a strained intermediate "aziridinium ion" which is very reactive towards DNA of tumor cell as well as normal cell resulting in various adverse side effects alogwith therapeutic implications. Over the last 75 years, due to its high reactivity and peripheral cytotoxicity, numerous modifications have been made in the area of nitrogen mustard to improve its efficacy as well as enhancing drug delivery specifically to tumor cells. This review mainly discusses the medicinal chemistry aspects in the development of various classes of nitrogen mustards (mechlorethamine, chlorambucil, melphalan, cyclophosphamide and steroidal based nitrogen mustards). The literature collection includes the historical and the latest developments in these areas. This comprehensive review also attempted to showcase the recent progress in the targeted delivery of nitrogen mustards that includes DNA directed nitrogen mustards, antibody directed enzyme prodrug therapy (ADEPT), gene directed enzyme prodrug therapy (GDEPT), nitrogen mustard activated by glutathione transferase, peptide based nitrogen mustards and CNS targeted nitrogen mustards. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Targeted Delivery of siRNA Therapeutics to Malignant Tumors

Directory of Open Access Journals (Sweden)

Qixin Leng

2017-01-01

Full Text Available Over the past 20 years, a diverse group of ligands targeting surface biomarkers or receptors has been identified with several investigated to target siRNA to tumors. Many approaches to developing tumor-homing peptides, RNA and DNA aptamers, and single-chain variable fragment antibodies by using phage display, in vitro evolution, and recombinant antibody methods could not have been imagined by researchers in the 1980s. Despite these many scientific advances, there is no reason to expect that the ligand field will not continue to evolve. From development of ligands based on novel or existing biomarkers to linking ligands to drugs and gene and antisense delivery systems, several fields have coalesced to facilitate ligand-directed siRNA therapeutics. In this review, we discuss the major categories of ligand-targeted siRNA therapeutics for tumors, as well as the different strategies to identify new ligands.

Cell mediated therapeutics for cancer treatment: Tumor homing cells as therapeutic delivery vehicles

Science.gov (United States)

Balivada, Sivasai

Many cell types were known to have migratory properties towards tumors and different research groups have shown reliable results regarding cells as delivery vehicles of therapeutics for targeted cancer treatment. Present report discusses proof of concept for 1. Cell mediated delivery of Magnetic nanoparticles (MNPs) and targeted Magnetic hyperthermia (MHT) as a cancer treatment by using in vivo mouse cancer models, 2. Cells surface engineering with chimeric proteins for targeted cancer treatment by using in vitro models. 1. Tumor homing cells can carry MNPs specifically to the tumor site and tumor burden will decrease after alternating magnetic field (AMF) exposure. To test this hypothesis, first we loaded Fe/Fe3O4 bi-magnetic NPs into neural progenitor cells (NPCs), which were previously shown to migrate towards melanoma tumors. We observed that NPCs loaded with MNPs travel to subcutaneous melanoma tumors. After alternating magnetic field (AMF) exposure, the targeted delivery of MNPs by the NPCs resulted in a mild decrease in tumor size (Chapter-2). Monocytes/macrophages (Mo/Ma) are known to infiltrate tumor sites, and also have phagocytic activity which can increase their uptake of MNPs. To test Mo/Ma-mediated MHT we transplanted Mo/Ma loaded with MNPs into a mouse model of pancreatic peritoneal carcinomatosis. We observed that MNP-loaded Mo/Ma infiltrated pancreatic tumors and, after AMF treatment, significantly prolonged the lives of mice bearing disseminated intraperitoneal pancreatic tumors (Chapter-3). 2. Targeted cancer treatment could be achieved by engineering tumor homing cell surfaces with tumor proteases cleavable, cancer cell specific recombinant therapeutic proteins. To test this, Urokinase and Calpain (tumor specific proteases) cleavable; prostate cancer cell (CaP) specific (CaP1 targeting peptide); apoptosis inducible (Caspase3 V266ED3)- rCasp3V266ED3 chimeric protein was designed in silico. Hypothesized membrane anchored chimeric protein (rCasp3V

Multirate delivery of multiple therapeutic agents from metal-organic frameworks

Directory of Open Access Journals (Sweden)

Alistair C. McKinlay

2014-12-01

Full Text Available The highly porous nature of metal-organic frameworks (MOFs offers great potential for the delivery of therapeutic agents. Here, we show that highly porous metal-organic frameworks can be used to deliver multiple therapeutic agents—a biologically active gas, an antibiotic drug molecule, and an active metal ion—simultaneously but at different rates. The possibilities offered by delivery of multiple agents with different mechanisms of action and, in particular, variable timescales may allow new therapy approaches. Here, we show that the loaded MOFs are highly active against various strains of bacteria.

Therapeutic limitations in tumor-specific CD8+ memory T cell engraftment

International Nuclear Information System (INIS)

Bathe, Oliver F; Dalyot-Herman, Nava; Malek, Thomas R

2003-01-01

Adoptive immunotherapy with cytotoxic T lymphocytes (CTL) represents an alternative approach to treating solid tumors. Ideally, this would confer long-term protection against tumor. We previously demonstrated that in vitro-generated tumor-specific CTL from the ovalbumin (OVA)-specific OT-I T cell receptor transgenic mouse persisted long after adoptive transfer as memory T cells. When recipient mice were challenged with the OVA-expressing E.G7 thymoma, tumor growth was delayed and sometimes prevented. The reasons for therapeutic failures were not clear. OT-I CTL were adoptively transferred to C57BL/6 mice 21 – 28 days prior to tumor challenge. At this time, the donor cells had the phenotypical and functional characteristics of memory CD8+ T cells. Recipients which developed tumor despite adoptive immunotherapy were analyzed to evaluate the reason(s) for therapeutic failure. Dose-response studies demonstrated that the degree of tumor protection was directly proportional to the number of OT-I CTL adoptively transferred. At a low dose of OT-I CTL, therapeutic failure was attributed to insufficient numbers of OT-I T cells that persisted in vivo, rather than mechanisms that actively suppressed or anergized the OT-I T cells. In recipients of high numbers of OT-I CTL, the E.G7 tumor that developed was shown to be resistant to fresh OT-I CTL when examined ex vivo. Furthermore, these same tumor cells no longer secreted a detectable level of OVA. In this case, resistance to immunotherapy was secondary to selection of clones of E.G7 that expressed a lower level of tumor antigen. Memory engraftment with tumor-specific CTL provides long-term protection against tumor. However, there are several limitations to this immunotherapeutic strategy, especially when targeting a single antigen. This study illustrates the importance of administering large numbers of effectors to engraft sufficiently efficacious immunologic memory. It also demonstrates the importance of targeting several

Tumor Vessel Compression Hinders Perfusion of Ultrasonographic Contrast Agents

Directory of Open Access Journals (Sweden)

Mirco Galiè

2005-05-01

Full Text Available Contrast-enhanced ultrasound (CEUS is an advanced approach to in vivo assessment of tumor vascularity and is being increasingly adopted in clinical oncology. It is based on 1- to 10 μm-sized gas microbubbles, which can cross the capillary beds of the lungs and are effective echo enhancers. It is known that high cell density, high transendothelial fluid exchange, and poorly functioning lymphatic circulation all provoke solid stress, which compresses vessels and drastically reduces tumor blood flow. Given their size, we supposed that the perfusion of microbubbles is affected by anatomic features of tumor vessels more than are contrast agents traditionally used in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI. Here, we compared dynamic information obtained from CEUS and DCE-MRI on two experimental tumor models exhibiting notable differences in vessel anatomy. We found that tumors with small, flattened vessels show a much higher resistance to microbubble perfusion than to MRI contrast agents, and appear scarcely vascularized at CEUS examination, despite vessel volume adequate for normal function. Thus, whereas CEUS alone could induce incorrect diagnosis when tumors have small or collapsed vessels, integrated analysis using CEUS and DCE-MRI allows in vivo identification of tumors with a vascular profile frequently associated with malignant phenotypes.

Epigenetic Modulating Agents as a New Therapeutic Approach in Multiple Myeloma

International Nuclear Information System (INIS)

Maes, Ken; Menu, Eline; Van Valckenborgh, Els; Van Riet, Ivan; Vanderkerken, Karin; De Bruyne, Elke

2013-01-01

Multiple myeloma (MM) is an incurable B-cell malignancy. Therefore, new targets and drugs are urgently needed to improve patient outcome. Epigenetic aberrations play a crucial role in development and progression in cancer, including MM. To target these aberrations, epigenetic modulating agents, such as DNA methyltransferase inhibitors (DNMTi) and histone deacetylase inhibitors (HDACi), are under intense investigation in solid and hematological cancers. A clinical benefit of the use of these agents as single agents and in combination regimens has been suggested based on numerous studies in pre-clinical tumor models, including MM models. The mechanisms of action are not yet fully understood but appear to involve a combination of true epigenetic changes and cytotoxic actions. In addition, the interactions with the BM niche are also affected by epigenetic modulating agents that will further determine the in vivo efficacy and thus patient outcome. A better understanding of the molecular events underlying the anti-tumor activity of the epigenetic drugs will lead to more rational drug combinations. This review focuses on the involvement of epigenetic changes in MM pathogenesis and how the use of DNMTi and HDACi affect the myeloma tumor itself and its interactions with the microenvironment

Experimental study of 99Tcm-tri-peptide as a novel tumor imaging agent

International Nuclear Information System (INIS)

Xie Wenhui; Cai Xiaojia; Liu Ciyi; Zeng Jun; Zhang Lihua; Lei Bei; Huang Gang

2011-01-01

Objective: To evaluate 99 Tc m -Arg-Glu-Ser ( 99 Tc m -RES) as a potential tumor imaging agent. Methods: RES was synthesized using solid phase peptide synthesis. The optimal labeling conditions of RES were determined under different reagents and reacting temperatures using SnC1 2 as reducing agent.The biodistribution of 99 Tc m -RES was studied in nude mice bearing human lung cancer A549. Results: The radiochemical purity of 99 Tc m -RES was up to 85% and the radiochemical purity was 75% ever after 6 h at room temperature. The tumor uptake of 99 Tc m -RES was obvious and the radioactivity ratios of tumor/blood, tumor/heart, tumor/liver, tumor/lung, tumor/spleen and tumor/muscle were 5.31, 1.88, 1.57, 3.58, 4.16 and 5.92, respectively at 6 h after 99 Tc m -RES injection. Gamma camera imaging showed that tumor uptake of 99 Tc m -RES was negative in rabbits with inflammatory mass but positive in those bearing tumor. The radioactivity ratio of tumor/inflammation was 3.12 at 6 h after injection. Conclusion: 99 Tc m -RES might possibly become a potential tumor imaging agent. (authors)

Naturally occurring, tumor-specific, therapeutic proteins.

Science.gov (United States)

Argiris, Konstantinos; Panethymitaki, Chrysoula; Tavassoli, Mahvash

2011-05-01

The emerging approach to cancer treatment known as targeted therapies offers hope in improving the treatment of therapy-resistant cancers. Recent understanding of the molecular pathogenesis of cancer has led to the development of targeted novel drugs such as monoclonal antibodies, small molecule inhibitors, mimetics, antisense and small interference RNA-based strategies, among others. These compounds act on specific targets that are believed to contribute to the development and progression of cancers and resistance of tumors to conventional therapies. Delivered individually or combined with chemo- and/or radiotherapy, such novel drugs have produced significant responses in certain types of cancer. Among the most successful novel compounds are those which target tyrosine kinases (imatinib, trastuzumab, sinutinib, cetuximab). However, these compounds can cause severe side-effects as they inhibit pathways such as epidermal growth factor receptor (EGFR) or platelet-derived growth factor receptor, which are also important for normal functions in non-transformed cells. Recently, a number of proteins have been identified which show a remarkable tumor-specific cytotoxic activity. This toxicity is independent of tumor type or specific genetic changes such as p53, pRB or EGFR aberrations. These tumor-specific killer proteins are either derived from common human and animal viruses such as E1A, E4ORF4 and VP3 (apoptin) or of cellular origin, such as TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) and MDA-7 (melanoma differentiation associated-7). This review aims to present a current overview of a selection of these proteins with preferential toxicity among cancer cells and will provide an insight into the possible mechanism of action, tumor specificity and their potential as novel tumor-specific cancer therapeutics.

Tumor Progression Locus 2 (Tpl2 Kinase as a Novel Therapeutic Target for Cancer: Double-Sided Effects of Tpl2 on Cancer

Directory of Open Access Journals (Sweden)

Hye Won Lee

2015-02-01

Full Text Available Tumor progression locus 2 (Tpl2 is a mitogen-activated protein kinase (MAPK kinase kinase (MAP3K that conveys various intra- and extra-cellular stimuli to effector proteins of cells provoking adequate adoptive responses. Recent studies have elucidated that Tpl2 is an indispensable signal transducer as an MAP3K family member in diverse signaling pathways that regulate cell proliferation, survival, and death. Since tumorigenesis results from dysregulation of cellular proliferation, differentiation, and apoptosis, Tpl2 participates in many decisive molecular processes of tumor development and progression. Moreover, Tpl2 is closely associated with cytokine release of inflammatory cells, which has crucial effects on not only tumor cells but also tumor microenvironments. These critical roles of Tpl2 in human cancers make it an attractive anti-cancer therapeutic target. However, Tpl2 contradictorily works as a tumor suppressor in some cancers. The double-sided effects of Tpl2 originate from the specific upstream and downstream signaling environment of each tumor, since Tpl2 interacts with various signaling components. This review summarizes recent studies concerning the possible roles of Tpl2 in human cancers and considers its possibility as a therapeutic target, against which novel anti-cancer agents could be developed.

Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-Resistant Prostate Cancer

Science.gov (United States)

2017-12-01

AWARD NUMBER: W81XWH-13-1-0163 TITLE: Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-resistant Prostate Cancer ...Prostate Cancer 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Feng Yang, Ph.D. 5d. PROJECT NUMBER 5e. TASK NUMBER E-Mail: fyang@bcm.edu...W81XWH-13-1-0163 " Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-resistant Prostate Cancer " Introduction AR signaling

Applications of inorganic nanoparticles as therapeutic agents

Science.gov (United States)

Kim, Taeho; Hyeon, Taeghwan

2014-01-01

During the last decade, various functional nanostructured materials with interesting optical, magnetic, mechanical and chemical properties have been extensively applied to biomedical areas including imaging, diagnosis and therapy. In therapeutics, most research has focused on the application of nanoparticles as potential delivery vehicles for drugs and genes, because nanoparticles in the size range of 2-100 nm can interact with biological systems at the molecular level, and allow targeted delivery and passage through biological barriers. Recent investigations have even revealed that several kinds of nanomaterials are intrinsically therapeutic. Not only can they passively interact with cells, but they can also actively mediate molecular processes to regulate cell functions. This can be seen in the treatment of cancer via anti-angiogenic mechanisms as well as the treatment of neurodegenerative diseases by effectively controlling oxidative stress. This review will present recent applications of inorganic nanoparticles as therapeutic agents in the treatment of disease.

Modulating the Tumor Microenvironment to Enhance Tumor Nanomedicine Delivery

Directory of Open Access Journals (Sweden)

Bo Zhang

2017-12-01

Full Text Available Nanomedicines including liposomes, micelles, and nanoparticles based on the enhanced permeability and retention (EPR effect have become the mainstream for tumor treatment owing to their superiority over conventional anticancer agents. Advanced design of nanomedicine including active targeting nanomedicine, tumor-responsive nanomedicine, and optimization of physicochemical properties to enable highly effective delivery of nanomedicine to tumors has further improved their therapeutic benefits. However, these strategies still could not conquer the delivery barriers of a tumor microenvironment such as heterogeneous blood flow, dense extracellular matrix, abundant stroma cells, and high interstitial fluid pressure, which severely impaired vascular transport of nanomedicines, hindered their effective extravasation, and impeded their interstitial transport to realize uniform distribution inside tumors. Therefore, modulation of tumor microenvironment has now emerged as an important strategy to improve nanomedicine delivery to tumors. Here, we review the existing strategies and approaches for tumor microenvironment modulation to improve tumor perfusion for helping more nanomedicines to reach the tumor site, to facilitate nanomedicine extravasation for enhancing transvascular transport, and to improve interstitial transport for optimizing the distribution of nanomedicines. These strategies may provide an avenue for the development of new combination chemotherapeutic regimens and reassessment of previously suboptimal agents.

Modulating the Tumor Microenvironment to Enhance Tumor Nanomedicine Delivery

Science.gov (United States)

Zhang, Bo; Hu, Yu; Pang, Zhiqing

2017-01-01

Nanomedicines including liposomes, micelles, and nanoparticles based on the enhanced permeability and retention (EPR) effect have become the mainstream for tumor treatment owing to their superiority over conventional anticancer agents. Advanced design of nanomedicine including active targeting nanomedicine, tumor-responsive nanomedicine, and optimization of physicochemical properties to enable highly effective delivery of nanomedicine to tumors has further improved their therapeutic benefits. However, these strategies still could not conquer the delivery barriers of a tumor microenvironment such as heterogeneous blood flow, dense extracellular matrix, abundant stroma cells, and high interstitial fluid pressure, which severely impaired vascular transport of nanomedicines, hindered their effective extravasation, and impeded their interstitial transport to realize uniform distribution inside tumors. Therefore, modulation of tumor microenvironment has now emerged as an important strategy to improve nanomedicine delivery to tumors. Here, we review the existing strategies and approaches for tumor microenvironment modulation to improve tumor perfusion for helping more nanomedicines to reach the tumor site, to facilitate nanomedicine extravasation for enhancing transvascular transport, and to improve interstitial transport for optimizing the distribution of nanomedicines. These strategies may provide an avenue for the development of new combination chemotherapeutic regimens and reassessment of previously suboptimal agents. PMID:29311946

Therapeutics targeting tumor immune escape: towards the development of new generation anticancer vaccines.

Science.gov (United States)

Mocellin, Simone; Nitti, Donato

2008-05-01

Despite the evidence that immune effectors can play a significant role in controlling tumor growth under natural conditions or in response to therapeutic manipulation, it is clear that malignant cells evade immune surveillance in most cases. Considering that anticancer vaccination has reached a plateau of results and currently no vaccination regimen is indicated as a standard anticancer therapy, the dissection of the molecular events underlying tumor immune escape is the necessary condition to make anticancer vaccines a therapeutic weapon effective enough to be implemented in the routine clinical setting. Recent years have witnessed significant advances in our understanding of the molecular mechanisms underlying tumor immune escape. These mechanistic insights are fostering the development of rationally designed therapeutics aimed at reverting the immunosuppressive circuits that undermine an effective antitumor immune response. In this review, the best characterized mechanisms that allow cancer cells to evade immune surveillance are overviewed and the most debated controversies constellating this complex field are highlighted. In addition, the latest therapeutic strategies devised to overcome tumor immune escape are described, with special regard to those entering clinical phase investigation. Copyright (c) 2007 Wiley-Periodicals, Inc.

EphB4 as a therapeutic target in mesothelioma

International Nuclear Information System (INIS)

Liu, Ren; Ferguson, Benjamin D; Zhou, Yue; Naga, Kranthi; Salgia, Ravi; Gill, Parkash S; Krasnoperov, Valery

2013-01-01

Malignant pleural mesothelioma (MPM) often develops decades following exposure to asbestos. Current best therapy produces a response in only half of patients, and the median survival with this therapy remains under a year. A search for novel targets and therapeutics is underway, and recently identified targets include VEGF, Notch, and EphB4-Ephrin-B2. Each of these targets has dual activity, promoting tumor cell growth as well as tumor angiogenesis. We investigated EphB4 expression in 39 human mesothelioma tissues by immunohistochemistry. Xenograft tumors established with human mesothelioma cells were treated with an EphB4 inhibitor (monomeric soluble EphB4 fused to human serum albumin, or sEphB4-HSA). The combinatorial effect of sEphB4-HSA and biologic agent was also studied. EphB4 was overexpressed in 72% of mesothelioma tissues evaluated, with 85% of epithelioid and 38% of sarcomatoid subtypes demonstrating overexpression. The EphB4 inhibitor sEphB4-HSA was highly active as a single agent to inhibit tumor growth, accompanied by tumor cell apoptosis and inhibition of PI3K and Src signaling. Combination of sEphB4-HSA and the anti-VEGF antibody (Bevacizumab) was superior to each agent alone and led to complete tumor regression. EphB4 is a potential therapeutic target in mesothelioma. Clinical investigation of sEphB4-HSA as a single agent and in combination with VEGF inhibitors is warranted

Irradiation promotes Akt-targeting therapeutic gene delivery to the tumor vasculature

International Nuclear Information System (INIS)

Sonveaux, Pierre; Frerart, Francoise; Bouzin, Caroline; Brouet, Agnes; Wever, Julie de; Jordan, Benedicte F.; Gallez, Bernard; Feron, Olivier

2007-01-01

Purpose: To determine whether radiation-induced increases in nitric oxide (NO) production can influence tumor blood flow and improve delivery of Akt-targeting therapeutic DNA lipocomplexes to the tumor. Methods and Materials: The contribution of NO to the endothelial response to radiation was identified using NO synthase (NOS) inhibitors and endothelial NOS (eNOS)-deficient mice. Reporter-encoding plasmids complexed with cationic lipids were used to document the tumor vascular specificity and the efficacy of in vivo lipofection after irradiation. A dominant-negative Akt gene construct was used to evaluate the facilitating effects of radiotherapy on the therapeutic transgene delivery. Results: The abundance of eNOS protein was increased in both irradiated tumor microvessels and endothelial cells, leading to a stimulation of NO release and an associated increase in tumor blood flow. Transgene expression was subsequently improved in the irradiated vs. nonirradiated tumor vasculature. This effect was not apparent in eNOS-deficient mice and could not be reproduced in irradiated cultured endothelial cells. Finally, we combined low-dose radiotherapy with a dominant-negative Akt gene construct and documented synergistic antitumor effects. Conclusions: This study offers a new rationale to combine radiotherapy with gene therapy, by directly exploiting the stimulatory effects of radiation on NO production by tumor endothelial cells. The preferential expression of the transgene in the tumor microvasculature underscores the potential of such an adjuvant strategy to limit the angiogenic response of irradiated tumors

Endothelial Thermotolerance Impairs Nanoparticle Transport in Tumors.

Science.gov (United States)

Bagley, Alexander F; Scherz-Shouval, Ruth; Galie, Peter A; Zhang, Angela Q; Wyckoff, Jeffrey; Whitesell, Luke; Chen, Christopher S; Lindquist, Susan; Bhatia, Sangeeta N

2015-08-15

The delivery of diagnostic and therapeutic agents to solid tumors is limited by physical transport barriers within tumors, and such restrictions directly contribute to decreased therapeutic efficacy and the emergence of drug resistance. Nanomaterials designed to perturb the local tumor environment with precise spatiotemporal control have demonstrated potential to enhance drug delivery in preclinical models. Here, we investigated the ability of one class of heat-generating nanomaterials called plasmonic nanoantennae to enhance tumor transport in a xenograft model of ovarian cancer. We observed a temperature-dependent increase in the transport of diagnostic nanoparticles into tumors. However, a transient, reversible reduction in this enhanced transport was seen upon reexposure to heating, consistent with the development of vascular thermotolerance. Harnessing these observations, we designed an improved treatment protocol combining plasmonic nanoantennae with diffusion-limited chemotherapies. Using a microfluidic endothelial model and genetic tools to inhibit the heat-shock response, we found that the ability of thermal preconditioning to limit heat-induced cytoskeletal disruption is an important component of vascular thermotolerance. This work, therefore, highlights the clinical relevance of cellular adaptations to nanomaterials and identifies molecular pathways whose modulation could improve the exposure of tumors to therapeutic agents. ©2015 American Association for Cancer Research.

Tumor Vessel Compression Hinders Perfusion of Ultrasonographic Contrast Agents1

Science.gov (United States)

Galiè, Mirco; D'Onofrio, Mirko; Montani, Maura; Amici, Augusto; Calderan, Laura; Marzola, Pasquina; Benati, Donatella; Merigo, Flavia; Marchini, Cristina; Sbarbati, Andrea

2005-01-01

Abstract Contrast-enhanced ultrasound (CEUS) is an advanced approach to in vivo assessment of tumor vascularity and is being increasingly adopted in clinical oncology. It is based on 1- to 10 µm-sized gas microbubbles, which can cross the capillary beds of the lungs and are effective echo enhancers. It is known that high cell density, high transendothelial fluid exchange, and poorly functioning lymphatic circulation all provoke solid stress, which compresses vessels and drastically reduces tumor blood flow. Given their size, we supposed that the perfusion of microbubbles is affected by anatomic features of tumor vessels more than are contrast agents traditionally used in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Here, we compared dynamic information obtained from CEUS and DCE-MRI on two experimental tumor models exhibiting notable differences in vessel anatomy. We found that tumors with small, flattened vessels show a much higher resistance to microbubble perfusion than to MRI contrast agents, and appear scarcely vascularized at CEUS examination, despite vessel volume adequate for normal function. Thus, whereas CEUS alone could induce incorrect diagnosis when tumors have small or collapsed vessels, integrated analysis using CEUS and DCE-MRI allows in vivo identification of tumors with a vascular profile frequently associated with malignant phenotypes. PMID:15967105

Concanavalin A: A potential anti-neoplastic agent targeting apoptosis, autophagy and anti-angiogenesis for cancer therapeutics

International Nuclear Information System (INIS)

Li, Wen-wen; Yu, Jia-ying; Xu, Huai-long; Bao, Jin-ku

2011-01-01

Highlights: → ConA induces cancer cell death targeting apoptosis and autophagy. → ConA inhibits cancer cell angiogenesis. → ConA is utilized in pre-clinical and clinical trials. -- Abstract: Concanavalin A (ConA), a Ca 2+ /Mn 2+ -dependent and mannose/glucose-binding legume lectin, has drawn a rising attention for its remarkable anti-proliferative and anti-tumor activities to a variety of cancer cells. ConA induces programmed cell death via mitochondria-mediated, P73-Foxo1a-Bim apoptosis and BNIP3-mediated mitochondrial autophagy. Through IKK-NF-κB-COX-2, SHP-2-MEK-1-ERK, and SHP-2-Ras-ERK anti-angiogenic pathways, ConA would inhibit cancer cell survival. In addition, ConA stimulates cell immunity and generates an immune memory, resisting to the same genotypic tumor. These biological findings shed light on new perspectives of ConA as a potential anti-neoplastic agent targeting apoptosis, autophagy and anti-angiogenesis in pre-clinical or clinical trials for cancer therapeutics.

Gadolinium-Loaded Solid Lipid Nanoparticles as a Tumor-Absorbable Contrast Agent for Early Diagnosis of Colorectal Tumors Using Magnetic Resonance Colonography.

Science.gov (United States)

Sun, Jihong; Zhang, Shizheng; Jiang, Shaojie; Bai, Weixian; Liu, Fei; Yuan, Hong; Ji, Jiansong; Luo, Jingfeng; Han, Guocan; Chen, Lumin; Jin, Yin; Hu, Peng; Yu, Lei; Yang, Xiaoming

2016-09-01

Magnetic resonance (MR) contrast agents focusing on special functions are required to improve cancer diagnosis, particularly in the early stages. Here, we designed multifunctional solid lipid nanoparticles (SLNs) with simultaneous loading of gadolinium (Gd) diethylenetriaminepentaacetic acid (Gd-DTPA) and octadecylamine fluorescein isothiocyanate (FITC) to obtain Gd-FITC-SLNs as a tumor-absorbable nanoparticle contrast agent for the histological confirmation of MR imaging (MRI) findings. Colorectal tumors were evaluated in vitro and in vivo via direct uptake of this contrast agent, which displayed reasonable T1 relaxivity and no significant cytotoxicity at the experimental concentrations in human colon carcinoma cells (HT29) and mouse colon carcinoma cells (CT26). In vitro cell uptake experiments demonstrated that contrast agent absorption by the two types of cancer cells was concentration-dependent in the safe concentration range. During in vivo MRI, transrectal infusion of Gd-FITC-SLNs showed more significant enhancement at the tumor site compared with the infusion of Gd-DTPA in female C57/BL mice with azoxymethane/dextran sulfate sodium-induced colorectal highgrade intraepithelial neoplasia. Subsequent confocal fluorescence microscopy demonstrated Gd-FITC-SLNs as highly concentrated green fluorescent spots distributed from the tumor capsule into the tumor. This study establishes the "proof-of-principle" of a new MRI technique wherein colorectal tumors are enhanced via direct absorption or uptake of the nanoparticle contrast agent.

MRI contrast agent concentration and tumor interstitial fluid pressure.

Science.gov (United States)

Liu, L J; Schlesinger, M

2016-10-07

The present work describes the relationship between tumor interstitial fluid pressure (TIFP) and the concentration of contrast agent for dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). We predict the spatial distribution of TIFP based on that of contrast agent concentration. We also discuss the cases for estimating tumor interstitial volume fraction (void fraction or porosity of porous medium), ve, and contrast volume transfer constant, K(trans), by measuring the ratio of contrast agent concentration in tissue to that in plasma. A linear fluid velocity distribution may reflect a quadratic function of TIFP distribution and lead to a practical method for TIFP estimation. To calculate TIFP, the parameters or variables should preferably be measured along the direction of the linear fluid velocity (this is in the same direction as the gray value distribution of the image, which is also linear). This method may simplify the calculation for estimating TIFP. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

The usefulness of US with contrast agent on breast tumors

International Nuclear Information System (INIS)

Jung, Hye An; Jung, Jung Im; Kim, Hak Hee; Son, Sang Bum; Byun, Jae Young; Lee, Jae Mun; Hahn, Sung Tae; Kim, Choon Yul

2000-01-01

To evaluate the usefulness of US with contrast agent breast tumors. Fifteen breast tumors in fourteen patients underwent color Doppler US before and after intravenous injection of a microbubble contrast agent (Levovist, Schering AG, Berlin, Germany). Benign lesions were 8 and malignant lesions were 7 among these. Real-time power Doppler ultrasonographic images were recorded on a videotape and representative images were color-printed. Tumor vascularity was analyzed on real-time images in regard to its presence or absence, and changes in diameter and number of vessels, presence or absence of blush around the vessels. Two observers reached a consensus. Results of malignant tumors were compared with those of benign tumors. Color Doppler signal intensity increased in 12 of 15 cases (80%). Number of vessel increased in 9 of 15 cases (60%) and diameter of vessel increased in 12 of 15 cases (80%). Vascular blush around the enhanced vessel was present in 5 of 15 patients (53%). Color Doppler signal increased in 5 of 8 benign lesions (63%) and 7 of 7 malignant lesions (100%). Number of vessel increased in 4 of 8 benign lesion (50%) and 5 of 7 malignant lesions (71%). Diameter of vessel increased in 5 of 8 benign lesions (63%) and 7 of 7 malignant lesions (100%). Blush around the enhanced vessel was present in one of 8 benign lesions (13%) and 4 of 7 malignant lesions (57%). The time to peak enhancement was shorter in malignant cases (mean=45 sec) than benign cases (mean=82 sec). US with contrast agent on breast tumors is effective to detect blood flow within the mass and may be helpful to differentiate malignant from benign lesions.

[Utilization of polymeric micelle magnetic resonance imaging (MRI) contrast agent for theranostic system].

Science.gov (United States)

Shiraishi, Kouichi

2013-01-01

We applied a polymeric micelle carrier system for the targeting of a magnetic resonance imaging (MRI) contrast agent. Prepared polymeric micelle MRI contrast agent exhibited a long circulation characteristic in blood, and considerable amount of the contrast agent was found to accumulate in colon 26 solid tumor by the EPR effect. The signal intensities of tumor area showed 2-folds increase in T1-weighted images at 24 h after i.v. injection. To observe enhancement of the EPR effect by Cderiv pretreatment on tumor targeting, we used the contrast agent for the evaluation by means of MRI. Cderiv pretreatment significantly enhanced tumor accumulation of the contrast agent. Interestingly, very high signal intensity in tumor region was found at 24 h after the contrast agent injection in Cderiv pretreated mice. The contrast agent visualized a microenvironmental change in tumor. These results indicate that the contrast agent exhibits potential use for tumor diagnostic agent. To combine with a polymeric micelle carrier system for therapeutic agent, the usage of the combination makes a new concept of "theranostic" for a better cancer treatment.

Recent Trends in Multifunctional Liposomal Nanocarriers for Enhanced Tumor Targeting

Directory of Open Access Journals (Sweden)

Federico Perche

2013-01-01

Full Text Available Liposomes are delivery systems that have been used to formulate a vast variety of therapeutic and imaging agents for the past several decades. They have significant advantages over their free forms in terms of pharmacokinetics, sensitivity for cancer diagnosis and therapeutic efficacy. The multifactorial nature of cancer and the complex physiology of the tumor microenvironment require the development of multifunctional nanocarriers. Multifunctional liposomal nanocarriers should combine long blood circulation to improve pharmacokinetics of the loaded agent and selective distribution to the tumor lesion relative to healthy tissues, remote-controlled or tumor stimuli-sensitive extravasation from blood at the tumor’s vicinity, internalization motifs to move from tumor bounds and/or tumor intercellular space to the cytoplasm of cancer cells for effective tumor cell killing. This review will focus on current strategies used for cancer detection and therapy using liposomes with special attention to combination therapies.

Targeting Mitochondrial Function to Treat Quiescent Tumor Cells in Solid Tumors

Directory of Open Access Journals (Sweden)

Xiaonan Zhang

2015-11-01

Full Text Available The disorganized nature of tumor vasculature results in the generation of microenvironments characterized by nutrient starvation, hypoxia and accumulation of acidic metabolites. Tumor cell populations in such areas are often slowly proliferating and thus refractory to chemotherapeutical drugs that are dependent on an active cell cycle. There is an urgent need for alternative therapeutic interventions that circumvent growth dependency. The screening of drug libraries using multicellular tumor spheroids (MCTS or glucose-starved tumor cells has led to the identification of several compounds with promising therapeutic potential and that display activity on quiescent tumor cells. Interestingly, a common theme of these drug screens is the recurrent identification of agents that affect mitochondrial function. Such data suggest that, contrary to the classical Warburg view, tumor cells in nutritionally-compromised microenvironments are dependent on mitochondrial function for energy metabolism and survival. These findings suggest that mitochondria may represent an “Achilles heel” for the survival of slowly-proliferating tumor cells and suggest strategies for the development of therapy to target these cell populations.

Basic study for development of new tumor specific agents for neutron capture therapy

International Nuclear Information System (INIS)

Matsumura, Akira; Nakagawa, Kunio; Yoshii, Yoshihiko; Nose, Tadao

1994-01-01

New tissue specific agents for neutron capture therapy was studied. Monoclonal labeled gadolinium-DTPA (Gd-MoAb) and porphyrin (ATN-10)-Gd-DTPA (Gd-ATN10) were studied as possible agents by using 9-L experimental brain tumor model. The tissue concentration were analyzed with magnetic resonance imaging (MRI) and inductively coupled plasma (ICP) analyzer. Gd-MoAb showed persistent retention in the tumor on MRI, but tissue gadolinium concentration was not detectable in the tumor by ICP analyzer, while there was high accumulation of Gd-MoAb in the liver. Gd-ATN10 showed prolonged and high accumulation in the tumor up to 48 hours on MRI. Gadolinium concentration reached up to 9 ppm in the tumor by 0.02 mmol/kg administration, but it disappeared within 6 hours after administration. This dissociation between MRI and ICP analysis was due to separation of ATN-10 and Gd-DTPA. As conclusions, the porphyrin compounds are potential agents for delivering gadolinium or boron specific to the tumor tissue, thus further improvement such as more stable conjugation between porphyrinfic to the tumor tissue, thus further improvement such as more stable conjugation between porphyrin and Gd-DTPA is needed. (author)

Orotracheal administration of contrast agents: a new protocol for brain tumor targeting.

Science.gov (United States)

Bianchi, Andrea; Moncelet, Damien; Lux, François; Plissonneau, Marie; Rizzitelli, Silvia; Ribot, Emeline Julie; Tassali, Nawal; Bouchaud, Véronique; Tillement, Olivier; Voisin, Pierre; Crémillieux, Yannick

2015-06-01

The development of new non-invasive diagnostic and therapeutic approaches is of paramount importance in order to improve the outcome of patients with glioblastoma (GBM). In this work we investigated a completely non-invasive pre-clinical protocol to effectively target and detect brain tumors through the orotracheal route, using ultra-small nanoparticles (USRPs) and MRI. A mouse model of GBM was developed. In vivo MRI acquisitions were performed before and after intravenous or orotracheal administration of the nanoparticles to identify and segment the tumor. The accumulation of the nanoparticles in neoplastic lesions was assessed ex vivo through fluorescence microscopy. Before the administration of contrast agents, MR images allowed the identification of the presence of abnormal brain tissue in 73% of animals. After orotracheal or intravenous administration of USRPs, in all the mice an excellent co-localization of the position of the tumor with MRI and histology was observed. The elimination time of the USRPs from the tumor after the orotracheal administration was approximately 70% longer compared with intravenous injection. MRI and USRPs were shown to be powerful imaging tools able to detect, quantify and longitudinally monitor the development of GBMs. The absence of ionizing radiation and high resolution of MRI, along with the complete non-invasiveness and good reproducibility of the proposed protocol, make this technique potentially translatable to humans. To our knowledge, this is the first time that the advantages of a needle-free orotracheal administration route have been demonstrated for the investigation of the pathomorphological changes due to GBMs. Copyright © 2015 John Wiley & Sons, Ltd.

Comparison of two brain tumor-localizing MRI agent. GD-BOPTA and GD-DTPA. MRI and ICP study of rat brain tumor model

International Nuclear Information System (INIS)

Zhang, T.; Matsumura, A.; Yamamoto, T.; Yoshida, F.; Nose, T.

2000-01-01

In this study, we compared the behavior of Gd-BOPTA as a brain tumor selective contrast agent with Gd-DTPA in a common dose of 0.1 mmol/kg. We performed a MRI study using those two agent as contrast material, and we measured tissue Gd-concentrations by ICP-AES. As a result, Gd-BOPTA showed a better MRI enhancement in brain tumor. ICP showed significantly greater uptake of Gd-BOPTA in tumor samples, at all time course peaked at 5 minutes after administration, Gd being retained for a longer time in brain tumor till 2 hours, without rapid elimination as Gd-DTPA. We conclude that Gd-BOPTA is a new useful contrast material for MR imaging in brain tumor and an effective absorption agent for neutron capture therapy for further research. (author)

Therapeutic neuroprotective agents for amyotrophic lateral sclerosis

Science.gov (United States)

Pandya, Rachna S.; Zhu, Haining; Li, Wei; Bowser, Robert; Friedlander, Robert M.

2014-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal chronic neurodegenerative disease whose hallmark is proteinaceous, ubiquitinated, cytoplasmic inclusions in motor neurons and surrounding cells. Multiple mechanisms proposed as responsible for ALS pathogenesis include dysfunction of protein degradation, glutamate excitotoxicity, mitochondrial dysfunction, apoptosis, oxidative stress, and inflammation. It is therefore essential to gain a better understanding of the underlying disease etiology and search for neuroprotective agents that might delay disease onset, slow progression, prolong survival, and ultimately reduce the burden of disease. Because riluzole, the only Food and Drug Administration (FDA)-approved treatment, prolongs the ALS patient’s life by only 3 months, new therapeutic agents are urgently needed. In this review, we focus on studies of various small pharmacological compounds targeting the proposed pathogenic mechanisms of ALS and discuss their impact on disease progression. PMID:23864030

Contrast agents for tumor diagnosis in magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Goto, Rensuke; Doi, Hisayoshi; Okada, Shoji [University of Shizuoka (Japan). School of Pharmaceutical Science; Yano, Masayuki; Katano, Susumu; Nakajima, Nobuaki

1992-01-01

In order to develop contrast agents for tumor diagnosis in magnetic resonance imaging (MRI), we investigated the effects of several gadolinium complexes on T{sub 1} relaxation time of proton in some tissues of Ehrlich solid tumor-bearing mice. L-Aspartic acid, L-glutamic acid, DL-homocysteine, L-glutamyl-glutamic acid, glutathione, sperimidine and ethylenediaminetetrakis (methylenephosphate) (EDTMP) were used as ligands for Gd{sup 3+}. Since each Gd-complex could not be purified except Gd-EDTMP, the mixture of GdCl{sub 3} and a ligand was administered intravenously. Among the compounds tested, the mixture of aspartic acid, glutathione or spermidine with GdCl{sub 3} showed almost the same or above reduction of T{sub 1} relaxation times in the tumor tissue compared with Gd-diethylenetriamine pentaacetic acid (Gd-DTPA) which is used clinically. Furthermore, the contrast-enhancing effect of the three mixtures in the tumor was observed by in vivo T{sub 1}-weighted magnetic resonance imaging. The in vivo tissue distribution using radioactive {sup 153}Gd{sup 3+} showed that these mixtures mentioned above were also taken up more highly in the tumor than {sup 153}GdCl{sub 3} itself and {sup 153}Gd-DTPA, suggesting the formation of Gd-complexes. However, the overall tissue distribution of the mixtures was similar to that of {sup 153}GdCl{sub 3} because the Gd-complexes were not purified. Gd-EDTMP exhibited the almost same effects with Gd-DTPA as a contrast agent. (author).

Dendrimer advances for the central nervous system delivery of therapeutics.

Science.gov (United States)

Xu, Leyuan; Zhang, Hao; Wu, Yue

2014-01-15

The effectiveness of noninvasive treatment for central nervous system (CNS) diseases is generally limited by the poor access of therapeutic agents into the CNS. Most CNS drugs cannot permeate into the brain parenchyma because of the blood-brain barrier (BBB), and overcoming this has become one of the most significant challenges in the development of CNS therapeutics. Rapid advances in nanotechnology have provided promising solutions to this challenge. This review discusses the latest applications of dendrimers in the treatment of CNS diseases with an emphasis on brain tumors. Dendrimer-mediated drug delivery, imaging, and diagnosis are also reviewed. The toxicity, biodistribution, and transport mechanisms in dendrimer-mediated delivery of CNS therapeutic agents bypassing or crossing the BBB are also discussed. Future directions and major challenges of dendrimer-mediated delivery of CNS therapeutic agents are included.

Applications of inorganic nanoparticles as therapeutic agents

International Nuclear Information System (INIS)

Kim, Taeho; Hyeon, Taeghwan

2014-01-01

During the last decade, various functional nanostructured materials with interesting optical, magnetic, mechanical and chemical properties have been extensively applied to biomedical areas including imaging, diagnosis and therapy. In therapeutics, most research has focused on the application of nanoparticles as potential delivery vehicles for drugs and genes, because nanoparticles in the size range of 2–100 nm can interact with biological systems at the molecular level, and allow targeted delivery and passage through biological barriers. Recent investigations have even revealed that several kinds of nanomaterials are intrinsically therapeutic. Not only can they passively interact with cells, but they can also actively mediate molecular processes to regulate cell functions. This can be seen in the treatment of cancer via anti-angiogenic mechanisms as well as the treatment of neurodegenerative diseases by effectively controlling oxidative stress. This review will present recent applications of inorganic nanoparticles as therapeutic agents in the treatment of disease. (topical review)

Cisplatin encapsulated nanoparticle as a therapeutic agent for anticancer treatment

Science.gov (United States)

Eka Putra, Gusti Ngurah Putu; Huang, Leaf; Hsu, Yih-Chih

2016-03-01

The knowledge of manipulating size of biomaterials encapsulated drug into nano-scale particles has been researched and developed in treating cancer. Cancer is the second worldwide cause of death, therefore it is critical to treat cancers challenging with therapeutic modality of various mechanisms. Our preliminary investigation has studied cisplatin encapsulated into lipid-based nanoparticle and examined the therapeutic effect on xenografted animal model. We used mice with tumor volume ranging from 195 to 214 mm3 and then few mice were grouped into three groups including: control (PBS), lipid platinum chloride (LPC) nanoparticles and CDDP (cis-diamminedichloroplatinum(II) at dose of 3mg cisplatin /kg body weight. The effect of the treatment was observed for 12 days post-injection. It showed that LPC NPs demonstrated a better therapeutic effect compared to CDDP at same 3mg cisplatin/kg drug dose of tumor size reduction, 96.6% and 11.1% respectively. In addition, mouse body weight loss of LPC, CDDP and PBS treated group are 12.1%, 24.3% and 1.4%. It means that by compared to CDDP group, LPC group demonstrated less side effect as not much reduction of body weight have found. Our findings have shown to be a potential modality to further investigate as a feasible cancer therapy modality.

In vivo preclinical photoacoustic imaging of tumor vasculature development and therapy

Science.gov (United States)

Laufer, Jan; Johnson, Peter; Zhang, Edward; Treeby, Bradley; Cox, Ben; Pedley, Barbara; Beard, Paul

2012-05-01

The use of a novel all-optical photoacoustic scanner for imaging the development of tumor vasculature and its response to a therapeutic vascular disrupting agent is described. The scanner employs a Fabry-Perot polymer film ultrasound sensor for mapping the photoacoustic waves and an image reconstruction algorithm based upon attenuation-compensated acoustic time reversal. The system was used to noninvasively image human colorectal tumor xenografts implanted subcutaneously in mice. Label-free three-dimensional in vivo images of whole tumors to depths of almost 10 mm with sub-100-micron spatial resolution were acquired in a longitudinal manner. This enabled the development of tumor-related vascular features, such as vessel tortuosity, feeding vessel recruitment, and necrosis to be visualized over time. The system was also used to study the temporal evolution of the response of the tumor vasculature following the administration of a therapeutic vascular disrupting agent (OXi4503). This revealed the well-known destruction and recovery phases associated with this agent. These studies illustrate the broader potential of this technology as an imaging tool for the preclinical and clinical study of tumors and other pathologies characterized by changes in the vasculature.

Therapeutically targeting cyclin D1 in primary tumors arising from loss of Ini1

Science.gov (United States)

Smith, Melissa E.; Cimica, Velasco; Chinni, Srinivasa; Jana, Suman; Koba, Wade; Yang, Zhixia; Fine, Eugene; Zagzag, David; Montagna, Cristina; Kalpana, Ganjam V.

2011-01-01

Rhabdoid tumors (RTs) are rare, highly aggressive pediatric malignancies with poor prognosis and with no standard or effective treatment strategies. RTs are characterized by biallelic inactivation of the INI1 tumor suppressor gene. INI1 directly represses CCND1 and activates cyclin-dependent kinase (cdk) inhibitors p16Ink4a and p21CIP. RTs are exquisitely dependent on cyclin D1 for genesis and survival. To facilitate translation of unique therapeutic strategies, we have used genetically engineered, Ini1+/− mice for therapeutic testing. We found that PET can be used to noninvasively and accurately detect primary tumors in Ini1+/− mice. In a PET-guided longitudinal study, we found that treating Ini1+/− mice bearing primary tumors with the pan-cdk inhibitor flavopiridol resulted in complete and stable regression of some tumors. Other tumors showed resistance to flavopiridol, and one of the resistant tumors overexpressed cyclin D1, more than flavopiridol-sensitive cells. The concentration of flavopiridol used was not sufficient to down-modulate the high level of cyclin D1 and failed to induce cell death in the resistant cells. Furthermore, FISH and PCR analyses indicated that there is aneuploidy and increased CCND1 copy number in resistant cells. These studies indicate that resistance to flavopiridol may be correlated to elevated cyclin D1 levels. Our studies also indicate that Ini1+/− mice are valuable tools for testing unique therapeutic strategies and for understanding mechanisms of drug resistance in tumors that arise owing to loss of Ini1, which is essential for developing effective treatment strategies against these aggressive tumors. PMID:21173237

Visualization of Tumor Angiogenesis Using MR Imaging Contrast Agent Gd-DTPA-anti-VEGF Receptor 2 Antibody Conjugate in a Mouse Tumor Model

International Nuclear Information System (INIS)

Jun, Hong Young; Yin, Hong Hua; Kim, Sun Hee; Park, Seong Hoon; Kim, Hun Soo; Yoon Kwon Ha Yoon

2010-01-01

To visualize tumor angiogenesis using the MRI contrast agent, Gd- DTPA-anti-VEGF receptor 2 antibody conjugate, with a 4.7-Tesla MRI instrument in a mouse model. We designed a tumor angiogenesis-targeting T1 contrast agent that was prepared by the bioconjugation of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) and an anti-vascular endothelial growth factor receptor-2 (VEGFR2) antibody. The specific binding of the agent complex to cells that express VEGFR2 was examined in cultured murine endothelial cells (MS-1 cells) with a 4.7-Tesla magnetic resonance imaging scanner. Angiogenesis-specific T1 enhancement was imaged with the Gd-DTPA-anti-VEGFR2 antibody conjugate using a CT-26 adenocarcinoma tumor model in eight mice. As a control, the use of the Gd-DTPA-anti-rat immunoglobulin G (Gd-DTPA-anti-rat IgG) was imaged with a tumor model in eight mice. Statistical significance was assessed using the Mann-Whitney test. Tumor tissue was examined by immunohistochemical analysis. The Gd-DTPA-anti-VEGFR2 antibody conjugate showed predominant binding to cultured endothelial cells that expressed a high level of VEGFR2. Signal enhancement was approximately three-fold for in vivo T1-weighted MR imaging with the use of the Gd-DTPA-anti-VEGFR2 antibody conjugate as compared with the Gd-DTPA-rat IgG in the mouse tumor model (p < 0.05). VEGFR2 expression in CT-26 tumor vessels was demonstrated using immunohistochemical staining. MR imaging using the Gd-DTPA-anti-VEGFR2 antibody conjugate as a contrast agent is useful in visualizing noninvasively tumor angiogenesis in a murine tumor model

Visualization of Tumor Angiogenesis Using MR Imaging Contrast Agent Gd-DTPA-anti-VEGF Receptor 2 Antibody Conjugate in a Mouse Tumor Model

Energy Technology Data Exchange (ETDEWEB)

Jun, Hong Young; Yin, Hong Hua; Kim, Sun Hee; Park, Seong Hoon; Kim, Hun Soo; Yoon Kwon Ha Yoon [Wonkwang University School of Medicine, Iksan (Korea, Republic of)

2010-08-15

To visualize tumor angiogenesis using the MRI contrast agent, Gd- DTPA-anti-VEGF receptor 2 antibody conjugate, with a 4.7-Tesla MRI instrument in a mouse model. We designed a tumor angiogenesis-targeting T1 contrast agent that was prepared by the bioconjugation of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) and an anti-vascular endothelial growth factor receptor-2 (VEGFR2) antibody. The specific binding of the agent complex to cells that express VEGFR2 was examined in cultured murine endothelial cells (MS-1 cells) with a 4.7-Tesla magnetic resonance imaging scanner. Angiogenesis-specific T1 enhancement was imaged with the Gd-DTPA-anti-VEGFR2 antibody conjugate using a CT-26 adenocarcinoma tumor model in eight mice. As a control, the use of the Gd-DTPA-anti-rat immunoglobulin G (Gd-DTPA-anti-rat IgG) was imaged with a tumor model in eight mice. Statistical significance was assessed using the Mann-Whitney test. Tumor tissue was examined by immunohistochemical analysis. The Gd-DTPA-anti-VEGFR2 antibody conjugate showed predominant binding to cultured endothelial cells that expressed a high level of VEGFR2. Signal enhancement was approximately three-fold for in vivo T1-weighted MR imaging with the use of the Gd-DTPA-anti-VEGFR2 antibody conjugate as compared with the Gd-DTPA-rat IgG in the mouse tumor model (p < 0.05). VEGFR2 expression in CT-26 tumor vessels was demonstrated using immunohistochemical staining. MR imaging using the Gd-DTPA-anti-VEGFR2 antibody conjugate as a contrast agent is useful in visualizing noninvasively tumor angiogenesis in a murine tumor model

In-vivo luminescence model for the study of tumor regression and regrowth following combination regimens with differentiation-promoting agents and photodynamic therapy

Science.gov (United States)

Rollakanti, K.; Anand, S.; Maytin, E. V.

2013-03-01

Photodynamic therapy with aminolevulinic acid can be modified by pretreatment regimens with drugs such as 5- Fluorouracil (5-FU) or Vitamin D (calcitriol) that enhance accumulation of protoporphyrin IX (PpIX) within tumor tissue which presumably will enhance the therapeutic response to light. However, histological approaches for monitoring therapeutic responses are poorly suited for studying long term survival because large numbers of mice need to be sacrificed. To address this limitation, a non-invasive model to monitor tumor regression and regrowth has been established. Breast cancer cells, stably transfected with firefly luciferase (MDA-Luc cell line), are implanted orthotopically in nude mice (0.25 - 1 x 106 cells/site), and monitored 0-60 min after s.c. injection of luciferin, with Xenogen in-vivo imaging system. Luminescence is detectable at day 1 post-implantation. Tumors are suitable for experimentation on day 6, when daily injections of pretreatment agents (5-FU, 300 mg/kg; calcitriol, 1 μg/kg) begin. On day 9, ALA (75 mg/kg i.p.) is given for 4 hr, followed by illumination (633 nm, 100 J/cm2). Tumor luminescence post- PDT is monitored daily and compared with caliper measurements. Pretreatments (5-FU, calcitriol) by themselves do not inhibit luciferase expression, and all tumors grow at a similar rate during the pretreatment period. Results from in vivo survival experiments can be correlated to survival responses of MDA-Luc cells grown in monolayer cultures +/- PDT and +/- pretreatments, and additional mechanistic information (e.g. Ki67 and E-cadherin expression) obtained. In summary, this noninvasive model will permit testing of the therapeutic survival advantages of various pretreatments during cPDT.

Dendrimer Advances for the Central Nervous System Delivery of Therapeutics

Science.gov (United States)

2013-01-01

The effectiveness of noninvasive treatment for central nervous system (CNS) diseases is generally limited by the poor access of therapeutic agents into the CNS. Most CNS drugs cannot permeate into the brain parenchyma because of the blood-brain barrier (BBB), and overcoming this has become one of the most significant challenges in the development of CNS therapeutics. Rapid advances in nanotechnology have provided promising solutions to this challenge. This review discusses the latest applications of dendrimers in the treatment of CNS diseases with an emphasis on brain tumors. Dendrimer-mediated drug delivery, imaging, and diagnosis are also reviewed. The toxicity, biodistribution, and transport mechanisms in dendrimer-mediated delivery of CNS therapeutic agents bypassing or crossing the BBB are also discussed. Future directions and major challenges of dendrimer-mediated delivery of CNS therapeutic agents are included. PMID:24274162

Spherical Nucleic Acids as Intracellular Agents for Nucleic Acid Based Therapeutics

Science.gov (United States)

Hao, Liangliang

Recent functional discoveries on the noncoding sequences of human genome and transcriptome could lead to revolutionary treatment modalities because the noncoding RNAs (ncRNAs) can be applied as therapeutic agents to manipulate disease-causing genes. To date few nucleic acid-based therapeutics have been translated into the clinic due to challenges in the delivery of the oligonucleotide agents in an effective, cell specific, and non-toxic fashion. Unmodified oligonucleotide agents are destroyed rapidly in biological fluids by enzymatic degradation and have difficulty crossing the plasma membrane without the aid of transfection reagents, which often cause inflammatory, cytotoxic, or immunogenic side effects. Spherical nucleic acids (SNAs), nanoparticles consisting of densely organized and highly oriented oligonucleotides, pose one possible solution to circumventing these problems in both the antisense and RNA interference (RNAi) pathways. The unique three dimensional architecture of SNAs protects the bioactive oligonucleotides from unspecific degradation during delivery and supports their targeting of class A scavenger receptors and endocytosis via a lipid-raft-dependent, caveolae-mediated pathway. Owing to their unique structure, SNAs are able to cross cell membranes and regulate target genes expression as a single entity, without triggering the cellular innate immune response. Herein, my thesis has focused on understanding the interactions between SNAs and cellular components and developing SNA-based nanostructures to improve therapeutic capabilities. Specifically, I developed a novel SNA-based, nanoscale agent for delivery of therapeutic oligonucleotides to manipulate microRNAs (miRNAs), the endogenous post-transcriptional gene regulators. I investigated the role of SNAs involving miRNAs in anti-cancer or anti-inflammation responses in cells and in in vivo murine disease models via systemic injection. Furthermore, I explored using different strategies to construct

A Zebrafish Heart Failure Model for Assessing Therapeutic Agents.

Science.gov (United States)

Zhu, Xiao-Yu; Wu, Si-Qi; Guo, Sheng-Ya; Yang, Hua; Xia, Bo; Li, Ping; Li, Chun-Qi

2018-03-20

Heart failure is a leading cause of death and the development of effective and safe therapeutic agents for heart failure has been proven challenging. In this study, taking advantage of larval zebrafish, we developed a zebrafish heart failure model for drug screening and efficacy assessment. Zebrafish at 2 dpf (days postfertilization) were treated with verapamil at a concentration of 200 μM for 30 min, which were determined as optimum conditions for model development. Tested drugs were administered into zebrafish either by direct soaking or circulation microinjection. After treatment, zebrafish were randomly selected and subjected to either visual observation and image acquisition or record videos under a Zebralab Blood Flow System. The therapeutic effects of drugs on zebrafish heart failure were quantified by calculating the efficiency of heart dilatation, venous congestion, cardiac output, and blood flow dynamics. All 8 human heart failure therapeutic drugs (LCZ696, digoxin, irbesartan, metoprolol, qiliqiangxin capsule, enalapril, shenmai injection, and hydrochlorothiazide) showed significant preventive and therapeutic effects on zebrafish heart failure (p failure model developed and validated in this study could be used for in vivo heart failure studies and for rapid screening and efficacy assessment of preventive and therapeutic drugs.

Tumor vascular-targeted co-delivery of anti-angiogenesis and chemotherapeutic agents by mesoporous silica nanoparticle-based drug delivery system for synergetic therapy of tumor

Directory of Open Access Journals (Sweden)

Li X

2015-12-01

Full Text Available Xiaoyu Li, Meiying Wu, Limin Pan, Jianlin Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, People’s Republic of China Abstract: To overcome the drawback of drug non-selectivity in traditional chemotherapy, the construction of multifunctional targeting drug delivery systems is one of the most effective and prevailing approaches. The intratumoral anti-angiogenesis and the tumor cell-killing are two basic approaches in fighting tumors. Herein we report a novel tumor vascular-targeting multidrug delivery system using mesoporous silica nanoparticles as carrier to co-load an antiangiogenic agent (combretastatin A4 and a chemotherapeutic drug (doxorubicin and conjugate with targeting molecules (iRGD peptide for combined anti-angiogenesis and chemotherapy. Such a dual-loaded drug delivery system is capable of delivering the two agents at tumor vasculature and then within tumors through a differentiated drug release strategy, which consequently results in greatly improved antitumor efficacy at a very low doxorubicin dose of 1.5 mg/kg. The fast release of the antiangiogenic agent at tumor vasculatures led to the disruption of vascular structure and had a synergetic effect with the chemotherapeutic drug slowly released in the following delivery of chemotherapeutic drug into tumors. Keywords: mesoporous silica nanoparticles, drug delivery, tumor vasculatures targeting, antiangiogenic agent

Localized sequence-specific release of a chemopreventive agent and an anticancer drug in a time-controllable manner to enhance therapeutic efficacy.

Science.gov (United States)

Pan, Wen-Yu; Lin, Kun-Ju; Huang, Chieh-Cheng; Chiang, Wei-Lun; Lin, Yu-Jung; Lin, Wei-Chih; Chuang, Er-Yuan; Chang, Yen; Sung, Hsing-Wen

2016-09-01

Combination chemotherapy with multiple drugs commonly requires several injections on various schedules, and the probability that the drug molecules reach the diseased tissues at the proper time and effective therapeutic concentrations is very low. This work elucidates an injectable co-delivery system that is based on cationic liposomes that are adsorbed on anionic hollow microspheres (Lipos-HMs) via electrostatic interaction, from which the localized sequence-specific release of a chemopreventive agent (1,25(OH)2D3) and an anticancer drug (doxorubicin; DOX) can be thermally driven in a time-controllable manner by an externally applied high-frequency magnetic field (HFMF). Lipos-HMs can greatly promote the accumulation of reactive oxygen species (ROS) in tumor cells by reducing their cytoplasmic expression of an antioxidant enzyme (superoxide dismutase) by 1,25(OH)2D3, increasing the susceptibility of cancer cells to the cytotoxic action of DOX. In nude mice that bear xenograft tumors, treatment with Lipos-HMs under exposure to HFMF effectively inhibits tumor growth and is the most effective therapeutic intervention among all the investigated. These empirical results demonstrate that the synergistic anticancer effects of sequential release of 1,25(OH)2D3 and DOX from the Lipos-HMs may have potential for maximizing DOX cytotoxicity, supporting more effective cancer treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selected Alkylating Agents Can Overcome Drug Tolerance of G0-like Tumor Cells and Eradicate BRCA1-Deficient Mammary Tumors in Mice.

Science.gov (United States)

Pajic, Marina; Blatter, Sohvi; Guyader, Charlotte; Gonggrijp, Maaike; Kersbergen, Ariena; Küçükosmanoğlu, Aslι; Sol, Wendy; Drost, Rinske; Jonkers, Jos; Borst, Piet; Rottenberg, Sven

2017-11-15

Purpose: We aimed to characterize and target drug-tolerant BRCA1-deficient tumor cells that cause residual disease and subsequent tumor relapse. Experimental Design: We studied responses to various mono- and bifunctional alkylating agents in a genetically engineered mouse model for BRCA1/p53 -mutant breast cancer. Because of the large intragenic deletion of the Brca1 gene, no restoration of BRCA1 function is possible, and therefore, no BRCA1-dependent acquired resistance occurs. To characterize the cell-cycle stage from which Brca1 -/- ;p53 -/- mammary tumors arise after cisplatin treatment, we introduced the fluorescent ubiquitination-based cell-cycle indicator (FUCCI) construct into the tumor cells. Results: Despite repeated sensitivity to the MTD of platinum drugs, the Brca1 -mutated mammary tumors are not eradicated, not even by a frequent dosing schedule. We show that relapse comes from single-nucleated cells delaying entry into the S-phase. Such slowly cycling cells, which are present within the drug-naïve tumors, are enriched in tumor remnants. Using the FUCCI construct, we identified nonfluorescent G 0 -like cells as the population most tolerant to platinum drugs. Intriguingly, these cells are more sensitive to the DNA-crosslinking agent nimustine, resulting in an increased number of multinucleated cells that lack clonogenicity. This is consistent with our in vivo finding that the nimustine MTD, among several alkylating agents, is the most effective in eradicating Brca1 -mutated mouse mammary tumors. Conclusions: Our data show that targeting G 0 -like cells is crucial for the eradication of BRCA1/p53-deficient tumor cells. This can be achieved with selected alkylating agents such as nimustine. Clin Cancer Res; 23(22); 7020-33. ©2017 AACR . ©2017 American Association for Cancer Research.

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.

Using PEGylated magnetic nanoparticles to describe the EPR effect in tumor for predicting therapeutic efficacy of micelle drugs.

Science.gov (United States)

Chen, Ling; Zang, Fengchao; Wu, Haoan; Li, Jianzhong; Xie, Jun; Ma, Ming; Gu, Ning; Zhang, Yu

2018-01-25

Micelle drugs based on a polymeric platform offer great advantages over liposomal drugs for tumor treatment. Although nearly all of the nanomedicines approved in the clinical use can passively target to the tumor tissues on the basis of an enhanced permeability and retention (EPR) effect, the nanodrugs have shown heterogenous responses in the patients. This phenomenon may be traced back to the EPR effect of tumor, which is extremely variable in the individuals from extensive studies. Nevertheless, there is a lack of experimental data describing the EPR effect and predicting its impact on therapeutic efficacy of nanoagents. Herein, we developed 32 nm magnetic iron oxide nanoparticles (MION) as a T 2 -weighted contrast agent to describe the EPR effect of each tumor by in vivo magnetic resonance imaging (MRI). The MION were synthesized by a thermal decomposition method and modified with DSPE-PEG2000 for biological applications. The PEGylated MION (Fe 3 O 4 @PEG) exhibited high r 2 of 571 mM -1 s -1 and saturation magnetization (M s ) of 94 emu g -1 Fe as well as long stability and favorable biocompatibility through the in vitro studies. The enhancement intensities of the tumor tissue from the MR images were quantitatively measured as TNR (Tumor/Normal tissue signal Ratio) values, which were correlated with the delay of tumor growth after intravenous administration of the PLA-PEG/PTX micelle drug. The results demonstrated that the group with the smallest TNR values (TNR EPR effect in patients for accurate medication guidance of micelle drugs in the future treatment of tumors.

Poly-S-Nitrosated Albumin as a Safe and Effective Multifunctional Antitumor Agent: Characterization, Biochemistry and Possible Future Therapeutic Applications

Directory of Open Access Journals (Sweden)

Yu Ishima

2013-01-01

Full Text Available Nitric oxide (NO is a ubiquitous molecule involved in multiple cellular functions. Inappropriate production of NO may lead to disease states. To date, pharmacologically active compounds that release NO within the body, such as organic nitrates, have been used as therapeutic agents, but their efficacy is significantly limited by unwanted side effects. Therefore, novel NO donors with better pharmacological and pharmacokinetic properties are highly desirable. The S-nitrosothiol fraction in plasma is largely composed of endogenous S-nitrosated human serum albumin (Mono-SNO-HSA, and that is why we are testing whether this albumin form can be therapeutically useful. Recently, we developed SNO-HSA analogs such as SNO-HSA with many conjugated SNO groups (Poly-SNO-HSA which were prepared using chemical modification. Unexpectedly, we found striking inverse effects between Poly-SNO-HSA and Mono-SNO-HSA. Despite the fact that Mono-SNO-HSA inhibits apoptosis, Poly-SNO-HSA possesses very strong proapoptotic effects against tumor cells. Furthermore, Poly-SNO-HSA can reduce or perhaps completely eliminate the multidrug resistance often developed by cancer cells. In this review, we forward the possibility that Poly-SNO-HSA can be used as a safe and effective multifunctional antitumor agent.

Potential Therapeutic Uses of p19ARF Mimics in Mammary Tumorigenesis

National Research Council Canada - National Science Library

Hann, Stephen R

2005-01-01

Since many breast tumors have deregulated c-Myc we hypothesize that an ARF mimic would be a valuable therapeutic agent for breast cancer to inhibit c-Myc-induced transformation/tumorigenesis without...

First-In-Class Small Molecule ONC201 Induces DR5 and Cell Death in Tumor but Not Normal Cells to Provide a Wide Therapeutic Index as an Anti-Cancer Agent.

Science.gov (United States)

Allen, Joshua E; Crowder, Roslyn N; Crowder, Roslyn; El-Deiry, Wafik S

2015-01-01

We previously identified ONC201 (TIC10) as a first-in-class orally active small molecule with robust antitumor activity that is currently in clinical trials in advanced cancers. Here, we further investigate the safety characteristics of ONC201 in preclinical models that reveal an excellent safety profile at doses that exceed efficacious doses by 10-fold. In vitro studies indicated a strikingly different dose-response relationship when comparing tumor and normal cells where maximal effects are much stronger in tumor cells than in normal cells. In further support of a wide therapeutic index, investigation of tumor and normal cell responses under identical conditions demonstrated large apoptotic effects in tumor cells and modest anti-proliferative effects in normal cells that were non-apoptotic and reversible. Probing the underlying mechanism of apoptosis indicated that ONC201 does not induce DR5 in normal cells under conditions that induce DR5 in tumor cells; DR5 is a pro-apoptotic TRAIL receptor previously linked to the anti-tumor mechanism of ONC201. GLP toxicology studies in Sprague-Dawley rats and beagle dogs at therapeutic and exaggerated doses revealed no dose-limiting toxicities. Observations in both species at the highest doses were mild and reversible at doses above 10-fold the expected therapeutic dose. The no observed adverse event level (NOAEL) was ≥42 mg/kg in dogs and ≥125 mg/kg in rats, which both correspond to a human dose of approximately 1.25 g assuming standard allometric scaling. These results provided the rationale for the 125 mg starting dose in dose escalation clinical trials that began in 2015 in patients with advanced cancer.

First-In-Class Small Molecule ONC201 Induces DR5 and Cell Death in Tumor but Not Normal Cells to Provide a Wide Therapeutic Index as an Anti-Cancer Agent.

Directory of Open Access Journals (Sweden)

Joshua E Allen

Full Text Available We previously identified ONC201 (TIC10 as a first-in-class orally active small molecule with robust antitumor activity that is currently in clinical trials in advanced cancers. Here, we further investigate the safety characteristics of ONC201 in preclinical models that reveal an excellent safety profile at doses that exceed efficacious doses by 10-fold. In vitro studies indicated a strikingly different dose-response relationship when comparing tumor and normal cells where maximal effects are much stronger in tumor cells than in normal cells. In further support of a wide therapeutic index, investigation of tumor and normal cell responses under identical conditions demonstrated large apoptotic effects in tumor cells and modest anti-proliferative effects in normal cells that were non-apoptotic and reversible. Probing the underlying mechanism of apoptosis indicated that ONC201 does not induce DR5 in normal cells under conditions that induce DR5 in tumor cells; DR5 is a pro-apoptotic TRAIL receptor previously linked to the anti-tumor mechanism of ONC201. GLP toxicology studies in Sprague-Dawley rats and beagle dogs at therapeutic and exaggerated doses revealed no dose-limiting toxicities. Observations in both species at the highest doses were mild and reversible at doses above 10-fold the expected therapeutic dose. The no observed adverse event level (NOAEL was ≥42 mg/kg in dogs and ≥125 mg/kg in rats, which both correspond to a human dose of approximately 1.25 g assuming standard allometric scaling. These results provided the rationale for the 125 mg starting dose in dose escalation clinical trials that began in 2015 in patients with advanced cancer.

The effect of anti-tumor necrosis factor alpha agents on postoperative anastomotic complications in Crohn's disease

DEFF Research Database (Denmark)

El-Hussuna, Alaa Abdul-Hussein H; Krag, Aleksander; Olaison, Gunnar

2013-01-01

Patients with Crohn's disease treated with anti-tumor necrosis factor alpha agents may have an increased risk of surgical complications.......Patients with Crohn's disease treated with anti-tumor necrosis factor alpha agents may have an increased risk of surgical complications....

A Functional Iron Oxide Nanoparticles Modified with PLA-PEG-DG as Tumor-Targeted MRI Contrast Agent.

Science.gov (United States)

Xiong, Fei; Hu, Ke; Yu, Haoli; Zhou, Lijun; Song, Lina; Zhang, Yu; Shan, Xiuhong; Liu, Jianping; Gu, Ning

2017-08-01

Tumor targeting could greatly promote the performance of magnetic nanomaterials as MRI (Magnetic Resonance Imaging) agent for tumor diagnosis. Herein, we reported a novel magnetic nanoparticle modified with PLA (poly lactic acid)-PEG (polyethylene glycol)-DG (D-glucosamine) as Tumor-targeted MRI Contrast Agent. In this work, we took use of the D-glucose passive targeting on tumor cells, combining it on PLA-PEG through amide reaction, and then wrapped the PLA-PEG-DG up to the Fe 3 O 4 @OA NPs. The stability and anti phagocytosis of Fe 3 O 4 @OA@PLA-PEG-DG was tested in vitro; the MRI efficiency and toxicity was also detected in vivo. These functional magnetic nanoparticles demonstrated good biocompatibility and stability both in vitro and in vivo. Cell experiments showed that Fe 3 O 4 @OA@PLA-PEG-DG nanoparticles exist good anti phagocytosis and high targetability. In vivo MRI images showed that the contrast effect of Fe 3 O 4 @OA@PLA-PEG-DG nanoparticles prevailed over the commercial non tumor-targeting magnetic nanomaterials MRI agent at a relatively low dose. The DG can validly enhance the tumor-targetting effect of Fe 3 O 4 @OA@PLA-PEG nanoparticle. Maybe MRI agents with DG can hold promise as tumor-targetting development in the future.

Oleuropein, a non-toxic olive iridoid, is an anti-tumor agent and cytoskeleton disruptor

International Nuclear Information System (INIS)

Hamdi, Hamdi K.; Castellon, Raquel

2005-01-01

Oleuropein, a non-toxic secoiridoid derived from the olive tree, is a powerful antioxidant and anti-angiogenic agent. Here, we show it to be a potent anti-cancer compound, directly disrupting actin filaments in cells and in a cell-free assay. Oleuropein inhibited the proliferation and migration of advanced-grade tumor cell lines in a dose-responsive manner. In a novel tube-disruption assay, Oleuropein irreversibly rounded cancer cells, preventing their replication, motility, and invasiveness; these effects were reversible in normal cells. When administered orally to mice that developed spontaneous tumors, Oleuropein completely regressed tumors in 9-12 days. When tumors were resected prior to complete regression, they lacked cohesiveness and had a crumbly consistency. No viable cells could be recovered from these tumors. These observations elevate Oleuropein from a non-toxic antioxidant into a potent anti-tumor agent with direct effects against tumor cells. Our data may also explain the cancer-protective effects of the olive-rich Mediterranean diet

Effect of Some Therapeutic Agents on the Radionuclides Excretion from Internally Contaminated Rats

International Nuclear Information System (INIS)

Aziz, M.; Mangood, Sh.A.; Sohsah, M.A.

2009-01-01

The present work was oriented to investigate the effectiveness of Prussian blue (PB), vermiculite and diethylenetriaminepentaacetic acid (CaDTPA) as therapeutic agents for the elimination of either 134 Cs or 60 Co from contaminated rats after intake of one of the isotopes. The study was performed by using 48 adult rats divided into 8 identical groups each of six rats having approximately the same body weight. The groups included a reference group, without isotope or therapeutic agent administration, four groups given one of the isotopes and four groups given the isotopes and treated with different therapeutic regimes. The isotope content of the treated and untreated contaminated rats were followed by daily whole body radiometric counting for three weeks. On plotting log % radionuclide retained as a function of time, elapsed between radionuclide administration and radiometric counting, straight lines were obtained. The results indicate that excretion can mostly be represented by two stages; the first is fast followed by a second slow stage. The % radionuclide excreted, the corresponding rate constant and the biological half-life of each stage was estimated. It was found that the application of PB + vermiculite is more efficient, to remove 134 Cs, from contaminated rats, than PB only and CaDTPA is more efficient to remove 60Co. Therefore, it is recommended to use the three therapeutic agents to remove both isotopes when taken simultaneously

Interactions of radiation with novel chemotherapeutic agents: Taxanes and nucleoside analogs

International Nuclear Information System (INIS)

Milas, Luka

1997-01-01

The combination of chemotherapeutic agents and radiotherapy is an appealing approach to improving the results of cancer treatment. By their independent action or interactive action chemotherapeutic drugs reduce cell burden in tumors undergoing radiotherapy, thereby increasing the chances of tumor control. In addition, the drugs may spatially cooperate with radiotherapy through their systemic action on metastatic disease. Recently, a number of new chemotherapeutic agents have been introduced for cancer treatment, which in addition have high potential to increase therapeutic ratio of radiotherapy. These agents include taxanes (paclitaxel and docetaxel) and the nucleoside analogs fludarabine and gemcitabine. Paclitaxel is a natural product isolated from the bark of Taxus brevifolia and taxotere is a semisynthetic analogue of paclitaxel prepared from needle extracts of Taxus baccata. By binding to cellular tubulin structures, taxanes interfere with tubulin polymerization and promote microtubule assembly, resulting in accumulation of cells in the radiosensitive G2 and M phases of the cell cycle. In vivo studies have demonstrated two major mechanisms of tumor radioenhancement by taxanes: mitotic arrest and tumor reoxygenation. Fludarabine and gemcitabine inhibit DNA synthesis and the repair of radiation-induced chromosome breaks. The mechanism of their radioenhancing activity include inhibition of repair of radiation induced damage, apoptosis induction and cell cycle synchronization. Because both classes of these agents affect radioresponse of normal dose-limiting tissues much less than that of tumors, they can greatly increase therapeutic ratio of radiotherapy. The objective of this course is to overview the rationale for using these drugs as radioenhancing agents, the experimental findings in preclinical studies, the mechanisms of their interaction, and the clinical application of these agents

In Vivo Visualizing the IFN-β Response Required for Tumor Growth Control in a Therapeutic Model of Polyadenylic-Polyuridylic Acid Administration.

Science.gov (United States)

Nocera, David Andrés; Roselli, Emiliano; Araya, Paula; Nuñez, Nicolás Gonzalo; Lienenklaus, Stefan; Jablonska, Jadwiga; Weiss, Siegfried; Gatti, Gerardo; Brinkmann, Melanie M; Kröger, Andrea; Morón, Gabriel; Maccioni, Mariana

2016-03-15

The crucial role that endogenously produced IFN-β plays in eliciting an immune response against cancer has recently started to be elucidated. Endogenous IFN-β has an important role in immune surveillance and control of tumor development. Accordingly, the role of TLR agonists as cancer therapeutic agents is being revisited via the strategy of intra/peritumoral injection with the idea of stimulating the production of endogenous type I IFN inside the tumor. Polyadenylic-polyuridylic acid (poly A:U) is a dsRNA mimetic explored empirically in cancer immunotherapy a long time ago with little knowledge regarding its mechanisms of action. In this work, we have in vivo visualized the IFN-β required for the antitumor immune response elicited in a therapeutic model of poly A:U administration. In this study, we have identified the role of host type I IFNs, cell populations that are sources of IFN-β in the tumor microenvironment, and other host requirements for tumor control in this model. One single peritumoral dose of poly A:U was sufficient to induce IFN-β, readily visualized in vivo. IFN-β production relied mainly on the activation of the transcription factor IFN regulatory factor 3 and the molecule UNC93B1, indicating that TLR3 is required for recognizing poly A:U. CD11c(+) cells were an important, but not the only source of IFN-β. Host type I IFN signaling was absolutely required for the reduced tumor growth, prolonged mice survival, and the strong antitumor-specific immune response elicited upon poly A:U administration. These findings add new perspectives to the use of IFN-β-inducing compounds in tumor therapy. Copyright © 2016 by The American Association of Immunologists, Inc.

Addressing challenges of heterogeneous tumor treatment through bispecific protein-mediated pretargeted drug delivery.

Science.gov (United States)

Yang, Qi; Parker, Christina L; McCallen, Justin D; Lai, Samuel K

2015-12-28

Tumors are frequently characterized by genomically and phenotypically distinct cancer cell subpopulations within the same tumor or between tumor lesions, a phenomenon termed tumor heterogeneity. These diverse cancer cell populations pose a major challenge to targeted delivery of diagnostic and/or therapeutic agents, as the conventional approach of conjugating individual ligands to nanoparticles is often unable to facilitate intracellular delivery to the full spectrum of cancer cells present in a given tumor lesion or patient. As a result, many cancers are only partially suppressed, leading to eventual tumor regrowth and/or the development of drug-resistant tumors. Pretargeting (multistep targeting) approaches involving the administration of 1) a cocktail of bispecific proteins that can collectively bind to the entirety of a mixed tumor population followed by 2) nanoparticles containing therapeutic and/or diagnostic agents that can bind to the bispecific proteins accumulated on the surface of target cells offer the potential to overcome many of the challenges associated with drug delivery to heterogeneous tumors. Despite its considerable success in improving the efficacy of radioimmunotherapy, the pretargeting strategy remains underexplored for a majority of nanoparticle therapeutic applications, especially for targeted delivery to heterogeneous tumors. In this review, we will present concepts in tumor heterogeneity, the shortcomings of conventional targeted systems, lessons learned from pretargeted radioimmunotherapy, and important considerations for harnessing the pretargeting strategy to improve nanoparticle delivery to heterogeneous tumors. Copyright © 2015 Elsevier B.V. All rights reserved.

Therapeutic applications of histone deacetylase inhibitors in sarcoma.

Science.gov (United States)

Tang, Fan; Choy, Edwin; Tu, Chongqi; Hornicek, Francis; Duan, Zhenfeng

2017-09-01

Sarcomas are a rare group of malignant tumors originating from mesenchymal stem cells. Surgery, radiation and chemotherapy are currently the only standard treatments for sarcoma. However, their response rates to chemotherapy are quite low. Toxic side effects and multi-drug chemoresistance make treatment even more challenging. Therefore, better drugs to treat sarcomas are needed. Histone deacetylase inhibitors (HDAC inhibitors, HDACi, HDIs) are epigenetic modifying agents that can inhibit sarcoma growth in vitro and in vivo through a variety of pathways, including inducing tumor cell apoptosis, causing cell cycle arrest, impairing tumor invasion and preventing metastasis. Importantly, preclinical studies have revealed that HDIs can not only sensitize sarcomas to chemotherapy and radiotherapy, but also increase treatment responses when combined with other chemotherapeutic drugs. Several phase I and II clinical trials have been conducted to assess the efficacy of HDIs either as monotherapy or in combination with standard chemotherapeutic agents or targeted therapeutic drugs for sarcomas. Combination regimen for sarcomas appear to be more promising than monotherapy when using HDIs. This review summarizes our current understanding and therapeutic applications of HDIs in sarcomas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gastric stromal tumor: two-phase dynamic CT findings with water as oral contrast agents

International Nuclear Information System (INIS)

Lee, Se Hyo; Cho, June Sik; Shin, Kyung Sook; Jeong, Ki Ho; Park, Jin Yong; Yu, Ho Jun; Kim, Young Min; Jeon, Kwang Jin

2000-01-01

To evaluate two-phase dynamic CT with water as oral contrast agents in the CT diagnosis of gastric stromal tumors. We retrospectively reviewed the CT findings in 21 patients with pathologically proven gastric stromal tumors. Six were found to be benign, twelve were malignant, and there were three cases of STUMP (stromal tumor uncertain malignant potential). Two-phase dynamic CT scans with water as oral contrast agents were obtained 60-70 secs (portal phase) and 3 mins (equilibrium phase) after the start of IV contrast administration. We determined the size, growth pattern, and enhancement pattern of the tumors and overlying mucosa, the presence or absence of ulceration and necrosis, tumor extent, and lymph nod and distant metastasis. The CT and pathologic findings were correlated. All six benign tumors and three STUMP were less than 5.5 cm in size, and during the portal phase showed round endogastric masses with highly enhanced, intact overlying mucosa. Twelve malignant tumors were 4.5-15.5 cm in size (mean, 11.5 cm); an endogastric mass was seen in three cases, an exogastric mass in one, and a mixed pattern in eight. On portal phase images the tumors were not significantly enhanced, but highly enhanced feeding vessels were noted in five larger tumors (greater than 10 cm). All 12 malignant tumors showed ulceration and necrosis, and interruption of overlying mucosa was clearly seen during the portal phase. We were readily able to evaluate tumor extent during this phase, and in ten malignant tumors there was no invasion of adjacent organs. Seven malignant tumors showed air density within their necrotic portion (p less than 0.05). On equilibrium phase images, all malignant tumors showed heterogeneous enhancement due to necrosis, and poorly enhanced overlying mucosa. Dynamic CT during the portal phase with water as oral contrast agents was useful for depicting the submucosal origin of gastric stromal tumors and for evaluating the extent of malignant stromal tumors. Our

Development of radiolanthanide labeled porphyrin complexes as possible therapeutic agents in beast carcinoma xenografts

Energy Technology Data Exchange (ETDEWEB)

Vahidfar, Nasim; Aghanejad, Ayuob; Beiki, Davood; Khalaj, Ali [Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of). Faculty of Pharmacy; Jalilian, Amir R.; Fazaeli, Yousef; Bahrami-Samani, Ali; Alirezapour, Behrooz; Erfani, Mostafa [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of). Radiopharmacy Research Group

2014-10-01

Radiolabeled porphyrins are potential tumor avid radiopharmaceuticals because of their behaviour in the human body, ability to complex various radionuclides, water solubility, low toxicity etc., in this work radio ytterbium/samarium porphyrin complexes have been developed. {sup 175}Yb and {sup 153}Sm labeled 5,10,15,20-tetrakis(3,4-dimethoxyphenyl) porphyrins ([{sup 175}Yb]-TDMPP/[{sup 153}Sm]-TDMPP) were prepared using 5,10,15,20-tetrakis(3,4-dimethoxyphenyl) porphyrin (H{sub 2}TDMPP) and [{sup 175}Yb]YbCl{sub 3} or [{sup 153}Sm]SmCl{sub 3} in 12-24 h at 60 C. Stability of the complexes were checked in final formulation and human serum for 24 h, followed by partition coefficient determination and biodistribution studies in wild type and breast carcinoma-bearing mice. The radiocomplexes were obtained with acceptable radiochemical purity (> 95% (paper chromatography) and > 96% (HPLC) for [{sup 175}Yb]-TDMPP and > 97% (paper chromatography) and > 98% (HPLC) for [{sup 153}Sm]-TDMPP) with specific activities of 12-15 GBq/mmol and 278 GBq/mmol at the end of bombardment for [{sup 175}Yb]-TDMPP and [{sup 153}Sm]-TDMPP respectively. The partition coefficients were determined for [{sup 175}Yb]-TDMPP and [{sup 153}Sm]-TDMPP (log P = 0.63 and log P = 0.96 respectively). The [{sup 175}Yb]-TDMPP complex is mostly washed out from the circulation through kidneys. Liver and spleen also demonstrated significant activity uptake in 72 h post injection. Also [{sup 153}Sm]-TDMPP, is mostly washed out from the circulation through kidneys, however lungs are the major accumulation sites. The [{sup 153}Sm]-TDMPP complex demonstrated significant targeted uptake in breast carcinoma xenografts with tumor: blood ratios of 10.67, 10.47 and 19.01 in 24, 48 and 72 h respectively. Also interesting tumor: kidney/liver ratios were obtained. {sup 153}Sm-TDMPP properties suggest an efficient tumor targeting agent with high tumor-avidity. Further investigation on the therapeutic properties must be

Optimization of a therapeutic electromagnetic field (EMF) to retard breast cancer tumor growth and vascularity

OpenAIRE

Cameron, Ivan L; Markov, Marko S; Hardman, W Elaine

2014-01-01

Background This study provided additional data on the effects of a therapeutic electromagnetic field (EMF) device on growth and vascularization of murine 16/C mammary adenocarcinoma cells implanted in C3H/HeJ mice. Methods The therapeutic EMF device generated a defined 120 Hz semi sine wave pulse signal of variable intensity. Murine 16/C mammary adenocarcinoma tumor fragments were implanted subcutaneously between the scapulae of syngeneic C3H mice. Once the tumor grew to 100 mm3, daily EMF tr...

EXCI-CEST: Exploiting pharmaceutical excipients as MRI-CEST contrast agents for tumor imaging.

Science.gov (United States)

Longo, Dario Livio; Moustaghfir, Fatima Zzahra; Zerbo, Alexandre; Consolino, Lorena; Anemone, Annasofia; Bracesco, Martina; Aime, Silvio

2017-06-15

Chemical Exchange Saturation Transfer (CEST) approach is a novel tool within magnetic resonance imaging (MRI) that allows visualization of molecules possessing exchangeable protons with water. Many molecules, employed as excipients for the formulation of finished drug products, are endowed with hydroxyl, amine or amide protons, thus can be exploitable as MRI-CEST contrast agents. Their high safety profiles allow them to be injected at very high doses. Here we investigated the MRI-CEST properties of several excipients (ascorbic acid, sucrose, N-acetyl-d-glucosamine, meglumine and 2-pyrrolidone) and tested them as tumor-detecting agents in two different murine tumor models (breast and melanoma cancers). All the investigated molecules showed remarkable CEST contrast upon i.v. administration in the range 1-3ppm according to the type of mobile proton groups. A marked increase of CEST contrast was observed in tumor regions up to 30min post injection. The combination of marked tumor contrast enhancement and lack of toxicity make these molecules potential candidates for the diagnosis of tumors within the MRI-CEST approach. Copyright © 2017 Elsevier B.V. All rights reserved.

Approaches to drug resistance in solid tumors : with emphasis on lung cancer

NARCIS (Netherlands)

Bakker, Marleen

2005-01-01

De novo or acquired resistance of tumor cells to anticancer agents remains a major problem for the therapeutic efficacy of chemotherapeutic drugs. Most solid tumors are intrinsically insensitive or acquire resistance after initial response to chemotherapy. Different mechanisms seem to play a role in

Therapeutic benefits in grid irradiation on Tomotherapy for bulky, radiation-resistant tumors.

Science.gov (United States)

Narayanasamy, Ganesh; Zhang, Xin; Meigooni, Ali; Paudel, Nava; Morrill, Steven; Maraboyina, Sanjay; Peacock, Loverd; Penagaricano, Jose

2017-08-01

Spatially fractionated radiation therapy (SFRT or grid therapy) has proven to be effective in management of bulky tumors. The aim of this project is to study the therapeutic ratio (TR) of helical Tomotherapy (HT)-based grid therapy using linear-quadratic cell survival model. HT-based grid (or HT-GRID) plan was generated using a patient-specific virtual grid pattern of high-dose cylindrical regions using MLCs. TR was defined as the ratio of normal tissue surviving fraction (SF) under HT-GRID irradiation to an open debulking field of an equivalent dose that result in the same tumor cell SF. TR was estimated from DVH data on ten HT-GRID patient plans with deep seated, bulky tumor. Dependence of the TR values on radiosensitivity of the tumor cells and prescription dose was analyzed. The mean ± standard deviation (SD) of TR was 4.0 ± 0.7 (range: 3.1-5.5) for the 10 patients with single fraction maximum dose of 20 Gy to GTV assuming a tumor cell SF at 2 Gy (SF2 t ) value of 0·5. In addition, the mean ± SD of TR values for SF2 t values of 0.3 and 0.7 were found to be 1 ± 0.1 and 18.0 ± 5.1, respectively. Reducing the prescription dose to 15 and 10 Gy lowered the respective TR values to 2.0 ± 0.2 and 1.2 ± 0.04 for a SF2 t value of 0.5. HT-GRID therapy demonstrates a significant therapeutic advantage over uniform dose from an open field irradiation for the same tumor cell kill. TR increases with the radioresistance of the tumor cells and with prescription dose.

Tumor biology and cancer therapy – an evolving relationship

Directory of Open Access Journals (Sweden)

Lother Ulrike

2009-08-01

Full Text Available Abstract The aim of palliative chemotherapy is to increase survival whilst maintaining maximum quality of life for the individual concerned. Although we are still continuing to explore the optimum use of traditional chemotherapy agents, the introduction of targeted therapies has significantly broadened the therapeutic options. Interestingly, the results from current trials put the underlying biological concept often into a new, less favorable perspective. Recent data suggested that altered pathways underlie cancer, and not just altered genes. Thus, an effective therapeutic agent will sometimes have to target downstream parts of a signaling pathway or physiological effects rather than individual genes. In addition, over the past few years increasing evidence has suggested that solid tumors represent a very heterogeneous group of cells with different susceptibility to cancer therapy. Thus, since therapeutic concepts and pathophysiological understanding are continuously evolving a combination of current concepts in tumor therapy and tumor biology is needed. This review aims to present current problems of cancer therapy by highlighting exemplary results from recent clinical trials with colorectal and pancreatic cancer patients and to discuss the current understanding of the underlying reasons.

Hybrid liposomes showing enhanced accumulation in tumors as theranostic agents in the orthotopic graft model mouse of colorectal cancer.

Science.gov (United States)

Okumura, Masaki; Ichihara, Hideaki; Matsumoto, Yoko

2018-11-01

Hybrid liposomes (HLs) can be prepared by simply sonicating a mixture of vesicular and micellar molecules in a buffer solution. This study aimed to elucidate the therapeutic effects and ability of HLs to detect (diagnosis) cancer in an orthotopic graft mouse model of colorectal cancer with HCT116 cells for the use of HLs as theranostic agents. In the absence of a chemotherapeutic drug, HLs exhibited therapeutic effects by inhibiting the growth of HCT116 colorectal cancer cells in vitro, possibly through an increase in apoptosis. Intravenously administered HLs also caused a remarkable reduction in the relative cecum weight in an orthotopic graft mouse model of colorectal cancer. A decrease in tumor size in the cecal sections was confirmed by histological analysis using HE staining. TUNEL staining indicated an induction of apoptosis in HCT116 cells in the orthotopic graft mouse model of colorectal cancer. For the detection (diagnosis) of colorectal cancer by HLs, the accumulation of HLs encapsulating a fluorescent probe (ICG) was observed in HCT116 cells in the in vivo colorectal cancer model following intravenous administration. These data indicate that HLs can accumulate in tumor cells in the cecum of the orthotopic graft mouse model of colorectal cancer for a prolonged period of time, and inhibit the growth of HCT116 cells.

Targeting the tumor microenvironment

Energy Technology Data Exchange (ETDEWEB)

Kenny, P.A.; Lee, G.Y.; Bissell, M.J.

2006-11-07

Despite some notable successes cancer remains, for the most part, a seemingly intractable problem. There is, however, a growing appreciation that targeting the tumor epithelium in isolation is not sufficient as there is an intricate mutually sustaining synergy between the tumor epithelial cells and their surrounding stroma. As the details of this dialogue emerge, new therapeutic targets have been proposed. The FDA has already approved drugs targeting microenvironmental components such as VEGF and aromatase and many more agents are in the pipeline. In this article, we describe some of the 'druggable' targets and processes within the tumor microenvironment and review the approaches being taken to disrupt these interactions.

PEGylated chitosan grafted with polyamidoaminedendron as tumor-targeted magnetic resonance imaging contrast agent

International Nuclear Information System (INIS)

Guangyue Zu; Xiaoyan Tong; Yi Cao; Ye Kuang; Yajie Zhang; Min Liu; Renjun Pei

2017-01-01

Macromolecular contrast agents labeled with targeting ligands are now receiving growing interest in tumor-targeted magnetic resonance imaging. In this study, a macromolecular contrast agent based on PEGylated chitosan was synthesized and characterized, and its application as an MRI contrast agent was then demonstrated both in vitro and in vivo. First, the chitosan backbone was partially grafted with poly(ethylene glycol), which was used to improve the in vivo stability, followed by modifying with azide groups. Second, alkynyl-terminated PAMAM dendron modified with gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) was synthesized and conjugated onto the chitosan backbone through click chemistry. Finally, the obtained mCA was further functionalized with folic acid to improve the target specificity. The obtained FA labeled mCA exhibited higher relaxivity (9.53 mM"-"1.s"-"1) relative to Gd-DTPA (4.25 mM"-"1.s"-"1) and showed negligible toxicity as determined by the WST assay. In vivo MRI results suggested that a relatively high signal enhancement was observed in the tumor region, which made it a promising candidate for tumor-targeted MRI CA. (authors)

Potential for tumor therapy with tritiated tetracycline. Summary evaluation

International Nuclear Information System (INIS)

Davis, R.C.; Wood, P.; Wood, L.L.; Mendelsohn, M.L.

1976-01-01

Reports of tetracycline accumulation in human and animal tumors have led a number of investigators to postulate that this drug, if radio-labeled, might have potential as a therapeutic or diagnostic agent. This paper describes attempts to investigate this potential for tritiated tetracycling. The therapeutic studies demonstrated that while a significant reduction in the growth rates of transplanted tumors could be obtained by the administration of heavy doses of TTC relative to uninjected controls, similar reductions were observed in the growth rates of tumors in animals receiving unlabeled TC. In the localization studies in rodents, the concentrations of TTC in normal tissues and tumors were compared and were correlated with the corresponding concentrations of 14 C-thymidine, a measure of proliferative activity

Applications of Genomic Sequencing in Pediatric CNS Tumors.

Science.gov (United States)

Bavle, Abhishek A; Lin, Frank Y; Parsons, D Williams

2016-05-01

Recent advances in genome-scale sequencing methods have resulted in a significant increase in our understanding of the biology of human cancers. When applied to pediatric central nervous system (CNS) tumors, these remarkable technological breakthroughs have facilitated the molecular characterization of multiple tumor types, provided new insights into the genetic basis of these cancers, and prompted innovative strategies that are changing the management paradigm in pediatric neuro-oncology. Genomic tests have begun to affect medical decision making in a number of ways, from delineating histopathologically similar tumor types into distinct molecular subgroups that correlate with clinical characteristics, to guiding the addition of novel therapeutic agents for patients with high-risk or poor-prognosis tumors, or alternatively, reducing treatment intensity for those with a favorable prognosis. Genomic sequencing has also had a significant impact on translational research strategies in pediatric CNS tumors, resulting in wide-ranging applications that have the potential to direct the rational preclinical screening of novel therapeutic agents, shed light on tumor heterogeneity and evolution, and highlight differences (or similarities) between pediatric and adult CNS tumors. Finally, in addition to allowing the identification of somatic (tumor-specific) mutations, the analysis of patient-matched constitutional (germline) DNA has facilitated the detection of pathogenic germline alterations in cancer genes in patients with CNS tumors, with critical implications for genetic counseling and tumor surveillance strategies for children with familial predisposition syndromes. As our understanding of the molecular landscape of pediatric CNS tumors continues to advance, innovative applications of genomic sequencing hold significant promise for further improving the care of children with these cancers.

Blocking Blood Flow to Solid Tumors by Destabilizing Tubulin: An Approach to Targeting Tumor Growth.

Science.gov (United States)

Pérez-Pérez, María-Jesús; Priego, Eva-María; Bueno, Oskía; Martins, Maria Solange; Canela, María-Dolores; Liekens, Sandra

2016-10-13

The unique characteristics of the tumor vasculature offer the possibility to selectively target tumor growth and vascularization using tubulin-destabilizing agents. Evidence accumulated with combretastatin A-4 (CA-4) and its prodrug CA-4P support the therapeutic value of compounds sharing this mechanism of action. However, the chemical instability and poor solubility of CA-4 demand alternative compounds that are able to surmount these limitations. This Perspective illustrates the different classes of compounds that behave similar to CA-4, analyzes their binding mode to αβ-tubulin according to recently available structural complexes, and includes described approaches to improve their delivery. In addition, dissecting the mechanism of action of CA-4 and analogues allows a closer insight into the advantages and drawbacks associated with these tubulin-destabilizing agents that behave as vascular disrupting agents (VDAs).

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

Polyradiomodification. Evaluation of the efficacy of the utilization of hyperglycemia in experimental hypoxiradiotherapy of tumors

International Nuclear Information System (INIS)

Kozin, S.V.; Dyuskaliev, Zh.D.; Yarmonenko, S.P.

1984-01-01

An experimental evaluation of the appropriateness of the use of short-term hyperglycemia combined with hypoxiradiotherapy of solid tumors is given. In comparing the response of tumors and overlying skin a conclusion has been made that gaseous hypoxia and the use of hyperglycemia separately yield in a considerable therapeutic benefit, and the use of the combination of these agents in some cases produces a greater therapeutic interval between tumor destruction and normal tissues. The mechanisms of the modification of radiation injuries of tumors and skin under the influence of the above two factors are discussed

Fluorine-Containing Taxoid Anticancer Agents and Their Tumor-Targeted Drug Delivery

OpenAIRE

Seitz, Joshua; Vineberg, Jacob G.; Zuniga, Edison S.; Ojima, Iwao

2013-01-01

A long-standing problem of conventional chemotherapy is the lack of tumor-specific treatments. Traditional chemotherapy relies on the premise that rapidly proliferating cancer cells are more likely to be killed by a cytotoxic agent. In reality, however, cytotoxic agents have very little or no specificity, which leads to systemic toxicity, causing undesirable severe side effects. Consequently, various “molecularly targeted cancer therapies” have been developed for use in specific cancers, incl...

Perspectives on Phytochemicals as Antibacterial Agents: An Outstanding Contribution to Modern Therapeutics.

Science.gov (United States)

Khatri, Savita; Kumar, Manish; Phougat, Neetu; Chaudhary, Renu; Chhillar, Anil Kumar

2016-01-01

Despite the considerable advancements in the development of antimicrobial agents, incidents of epidemics due to multi drug resistance in microorganisms have created a massive hazard to mankind. Due to increased resistance against conventional antibiotics, researchers and pharmaceutical industries are more concerned about novel therapeutic agents for the prevention of bacterial infections. Enormous wealth of traditional system of medicine gains importance in health therapies over again. With ancient credentials of potent medicinal plants, various herbal remedies came forward for the management of bacterial infections. The Ayurvedic approach facilitates the development of new therapeutic agents due to structural and functional diversity among phytochemicals. The abundance and diversity is responsible for the characterization of new lead structures from medicinal plants. Industrial interest has increased due to recent research advancements viz. synergistic and high-throughput screening approach for the evaluation of vast variety of phytochemicals. The review certainly emphasizes on the traditional medicines as alternatives to conventional chemotherapeutic drugs. The review briefly describes mode of action of various antibiotics and resistance mechanisms. This review focuses on the chemical diversity and various mechanisms of action of phytochemicals against bacterial pathogens.

Imaging tumor hypoxia: Blood-borne delivery of imaging agents is fundamentally different in hypoxia subtypes

Directory of Open Access Journals (Sweden)

Peter Vaupel

2014-03-01

Full Text Available Hypoxic tissue subvolumes are a hallmark feature of solid malignant tumors, relevant for cancer therapy and patient outcome because they increase both the intrinsic aggressiveness of tumor cells and their resistance to several commonly used anticancer strategies. Pathogenetic mechanisms leading to hypoxia are diverse, may coexist within the same tumor and are commonly grouped according to the duration of their effects. Chronic hypoxia is mainly caused by diffusion limitations resulting from enlarged intercapillary distances and adverse diffusion geometries and — to a lesser extent — by hypoxemia, compromised perfusion or long-lasting microregional flow stops. Conversely, acute hypoxia preferentially results from transient disruptions in perfusion. While each of these features of the tumor microenvironment can contribute to a critical reduction of oxygen availability, the delivery of imaging agents (as well as nutrients and anticancer agents may be compromised or remain unaffected. Thus, a critical appraisal of the effects of the various mechanisms leading to hypoxia with regard to the blood-borne delivery of imaging agents is necessary to judge their ability to correctly represent the hypoxic phenotype of solid malignancies.

Impact of the scintigraphy of somatostatin receptors upon the therapeutic strategy in patients bearing digestive endocrine tumors

International Nuclear Information System (INIS)

Lebtahi, R.; Cadiot, G.; Genin, R.; Delahaye, N.; Faraggi, M.; Daou, D.; Peker, C.; Migon, M.; Le Guludec, D.

1997-01-01

The scintigraphy of somatostatin receptors (SSR) is a sensible method for detecting the gastroenteric-pancreatic endocrine tumors and their metastases. The aim of this study is to evaluate the clinical impact of the results of SSR in taking patients in therapeutic charge. A hundred and sixty patients bearing biologically and/or histologically proved digestive endocrine tumors were prospectively studied. The patients were classified in 3 groups: group I - 90 patients with no known metastases; group II - 59 patients with liver metastases and group III - 11 patients with known extra-hepatic metastases. The results of the scintigraphy were compared with those of conventional imaging. The following results were obtained: in group 1 (90 patients) the conventional imaging has allowed detecting 53 primitive tumors in 44 patients. The SSR visualized 68% of these sites and has detected 26 supplementary primitive sites in 20 patients and 29 metastatic sites in 25 patients. In group II the scintigraphy has detected 95% of hepatic metastases and revealed 23 new metastasis sites and 18/59 patients. In group III the scintigraphy has detected 11 new sites in 7 patients. The results of scintigraphy modified the patient's classification in 38 cases (24%). The therapeutic strategy was modified for 40 patients (25%). In conclusion, the scintigraphy of somatostatin receptors is able to detect a significant number of digestive endocrine tumors what has important implications for therapeutical planning of the treatment of patients. It must be carried out during pre-therapeutic extension examination of these tumors

Evaluation of 18F-labeled icotinib derivatives as potential PET agents for tumor imaging

International Nuclear Information System (INIS)

Hongyu Ren; Hongyu Ning; Jin Chang; Mingxia Zhao; Yong He; Yan Chong; Chuanmin Qi

2016-01-01

In this study, three 18 F-labeled crown ether fused anilinoquinazoline derivatives ([ 18 F]11a-c) were synthesized and evaluated as potential tumor imaging probes. The biodistribution results of [ 18 F]11b were good. Compared with [ 18 F]-fludeoxyglucose and l-[ 18 F]-fluoroethyltyrosine in the same animal model, [ 18 F]11b had better tumor/brain, tumor/muscle, and tumor/blood uptake ratios. Overall, these results suggest that [ 18 F]11b is promising as a tumor imaging agent for positron emission tomography. (author)

Evaluation of radiolabeled ruthenium compounds as tumor-localizing agents

International Nuclear Information System (INIS)

Srivastava, S.C.; Richards, P.; Meinken, G.E.; Som, P.; Atkins, H.L.; Larson, S.M.; Grunbaum, Z.; Rasey, J.S.; Clarke, M.H.; Dowling, M.

1979-01-01

This work introduces a new class of radiopharmaceuticals based on ruthenium-97. The excellent physical properties of Ru-97, the high chemical reactivity of Ru, the potential antitumor activity of several Ru coordination compounds, and BLIP production of Ru-97, provide a unique combination for the application of this isotope in nuclear oncology. A systematic study was undertaken on the synthesis, characterization, and evaluation of a number of ruthenium-labeled compounds. In a variety of animal tumor models, several compounds show considerable promise as tumor-localizing agents when compared to gallium-67 citrate. The compounds studied (with Ru in different oxidation states) include ionic Ru, a number of hydrophilic and lipophilic chelates, and various ammine derivatives

Microenvironment acidity as a major determinant of tumor chemoresistance: Proton pump inhibitors (PPIs) as a novel therapeutic approach.

Science.gov (United States)

Taylor, Sophie; Spugnini, Enrico Pierluigi; Assaraf, Yehuda G; Azzarito, Tommaso; Rauch, Cyril; Fais, Stefano

2015-11-01

Despite the major progresses in biomedical research and the development of novel therapeutics and treatment strategies, cancer is still among the dominant causes of death worldwide. One of the crucial challenges in the clinical management of cancer is primary (intrinsic) and secondary (acquired) resistance to both conventional and targeted chemotherapeutics. Multiple mechanisms have been identifiedthat underlie intrinsic and acquired chemoresistance: these include impaired drug uptake, increased drug efflux, deletion of receptors, altered drug metabolism, quantitative and qualitative alterations in drug targets, increased DNA damage repair and various mechanisms of anti-apoptosis. The fast efflux of anticancer drugs mediated by multidrug efflux pumps and the partial or complete reversibility of chemoresistance combined with the absence of genetic mutations suggests a multifactorial process. However, a growing body of recent evidence suggests that chemoresistance is often triggered by the highly acidic microenvironment of tumors. The vast majority of drugs, including conventional chemotherapeutics and more recent biological agents, are weak bases that are quickly protonated and neutralized in acidic environments, such as the extracellular microenvironment and the acidic organelles of tumor cells. It is therefore essential to develop new strategies to overcome the entrapment and neutralization of weak base drugs. One such strategy is the use of proton pump inhibitors which can enhance tumor chemosensitivity by increasing the pH of the tumor microenvironment. Recent clinical trials in animals with spontaneous tumors have indicated that patient alkalization is capable of reversing acquired chemoresistance in a large percentage of tumors that are refractory to chemotherapy. Of particular interest was the benefit of alkalization for patients undergoing metronomic regimens which are becoming more widely used in veterinary medicine. Overall, these results provide

Immune evasion in cancer: Mechanistic basis and therapeutic strategies.

Science.gov (United States)

Vinay, Dass S; Ryan, Elizabeth P; Pawelec, Graham; Talib, Wamidh H; Stagg, John; Elkord, Eyad; Lichtor, Terry; Decker, William K; Whelan, Richard L; Kumara, H M C Shantha; Signori, Emanuela; Honoki, Kanya; Georgakilas, Alexandros G; Amin, Amr; Helferich, William G; Boosani, Chandra S; Guha, Gunjan; Ciriolo, Maria Rosa; Chen, Sophie; Mohammed, Sulma I; Azmi, Asfar S; Keith, W Nicol; Bilsland, Alan; Bhakta, Dipita; Halicka, Dorota; Fujii, Hiromasa; Aquilano, Katia; Ashraf, S Salman; Nowsheen, Somaira; Yang, Xujuan; Choi, Beom K; Kwon, Byoung S

2015-12-01

Cancer immune evasion is a major stumbling block in designing effective anticancer therapeutic strategies. Although considerable progress has been made in understanding how cancers evade destructive immunity, measures to counteract tumor escape have not kept pace. There are a number of factors that contribute to tumor persistence despite having a normal host immune system. Immune editing is one of the key aspects why tumors evade surveillance causing the tumors to lie dormant in patients for years through "equilibrium" and "senescence" before re-emerging. In addition, tumors exploit several immunological processes such as targeting the regulatory T cell function or their secretions, antigen presentation, modifying the production of immune suppressive mediators, tolerance and immune deviation. Besides these, tumor heterogeneity and metastasis also play a critical role in tumor growth. A number of potential targets like promoting Th1, NK cell, γδ T cell responses, inhibiting Treg functionality, induction of IL-12, use of drugs including phytochemicals have been designed to counter tumor progression with much success. Some natural agents and phytochemicals merit further study. For example, use of certain key polysaccharide components from mushrooms and plants have shown to possess therapeutic impact on tumor-imposed genetic instability, anti-growth signaling, replicative immortality, dysregulated metabolism etc. In this review, we will discuss the advances made toward understanding the basis of cancer immune evasion and summarize the efficacy of various therapeutic measures and targets that have been developed or are being investigated to enhance tumor rejection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Down-regulation of HSP27 sensitizes TRAIL-resistant tumor cell to TRAIL-induced apoptosis

DEFF Research Database (Denmark)

Zhuang, Hongqin; Jiang, Weiwei; Cheng, Wei

2010-01-01

Tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) has recently emerged as a cancer therapeutic agent because it preferentially induces apoptosis in human cancer over normal cells. Most tumor cells, including lung cancer cell line A549, unfortunately, are resistant to TRAIL tre...

An update on anti-TNF agents in ulcerative colitis

NARCIS (Netherlands)

Samaan, Mark A.; Bagi, Preet; Vande Casteele, Niels; D'Haens, Geert R.; Levesque, Barrett G.

2014-01-01

Anti-tumor necrosis factor-α agents are key therapeutic options for the treatment of ulcerative colitis. Their efficacy and safety have been shown in large randomized controlled trials. The key evidence gained from these trials of infliximab, adalimumab, and golimumab is reviewed along with their

Targeted Anticancer Immunotoxins and Cytotoxic Agents with Direct Killing Moieties

Directory of Open Access Journals (Sweden)

Koji Kawakami

2006-01-01

Full Text Available Despite the progress of the bioinformatics approach to characterize cell-surface antigens and receptors on tumor cells, it remains difficult to generate novel cancer vaccines or neutralizing monoclonal antibody therapeutics. Among targeted cancer therapeutics, biologicals with targetable antibodies or ligands conjugated or fused to toxins or chemicals for direct cell-killing ability have been developed over the last 2 decades. These conjugated or fused chimeric proteins are termed immunotoxins or cytotoxic agents. Two agents, DAB389IL-2 (ONTAKTM targeting the interleukin-2 receptor and CD33-calicheamicin (Mylotarg®, have been approved by the FDA for cutaneous T-cell lymphoma (CTCL and relapsed acute myeloid leukemia (AML, respectively. Such targetable agents, including RFB4(dsFv-PE38 (BL22, IL13-PE38QQR, and Tf-CRM107, are being tested in clinical trials. Several agents using unique technology such as a cleavable adapter or immunoliposomes with antibodies are also in the preclinical stage. This review summarizes the generation, mechanism, and development of these agents. In addition, possible future directions of this therapeutic approach are discussed.

Monte Carlo calculation of the maximum therapeutic gain of tumor antivascular alpha therapy

Energy Technology Data Exchange (ETDEWEB)

Huang, Chen-Yu; Oborn, Bradley M.; Guatelli, Susanna; Allen, Barry J. [Centre for Experimental Radiation Oncology, St. George Clinical School, University of New South Wales, Kogarah, New South Wales 2217 (Australia); Illawarra Cancer Care Centre, Wollongong, New South Wales 2522, Australia and Centre for Medical Radiation Physics, University of Wollongong, New South Wales 2522 (Australia); Centre for Medical Radiation Physics, University of Wollongong, New South Wales 2522 (Australia); Centre for Experimental Radiation Oncology, St. George Clinical School, University of New South Wales, Kogarah, New South Wales 2217 (Australia)

2012-03-15

Purpose: Metastatic melanoma lesions experienced marked regression after systemic targeted alpha therapy in a phase 1 clinical trial. This unexpected response was ascribed to tumor antivascular alpha therapy (TAVAT), in which effective tumor regression is achieved by killing endothelial cells (ECs) in tumor capillaries and, thus, depriving cancer cells of nutrition and oxygen. The purpose of this paper is to quantitatively analyze the therapeutic efficacy and safety of TAVAT by building up the testing Monte Carlo microdosimetric models. Methods: Geant4 was adapted to simulate the spatial nonuniform distribution of the alpha emitter {sup 213}Bi. The intraluminal model was designed to simulate the background dose to normal tissue capillary ECs from the nontargeted activity in the blood. The perivascular model calculates the EC dose from the activity bound to the perivascular cancer cells. The key parameters are the probability of an alpha particle traversing an EC nucleus, the energy deposition, the lineal energy transfer, and the specific energy. These results were then applied to interpret the clinical trial. Cell survival rate and therapeutic gain were determined. Results: The specific energy for an alpha particle hitting an EC nucleus in the intraluminal and perivascular models is 0.35 and 0.37 Gy, respectively. As the average probability of traversal in these models is 2.7% and 1.1%, the mean specific energy per decay drops to 1.0 cGy and 0.4 cGy, which demonstrates that the source distribution has a significant impact on the dose. Using the melanoma clinical trial activity of 25 mCi, the dose to tumor EC nucleus is found to be 3.2 Gy and to a normal capillary EC nucleus to be 1.8 cGy. These data give a maximum therapeutic gain of about 180 and validate the TAVAT concept. Conclusions: TAVAT can deliver a cytotoxic dose to tumor capillaries without being toxic to normal tissue capillaries.

Preparation of 99mTc-Ancitabine as a Possible Tumor Imaging Agent

International Nuclear Information System (INIS)

Ibrahim, I.T.; Attallah, K.M.

2010-01-01

Ancitabine is one of the potent chemotherapeutic anticancer drugs. Tc-Ancitabine ( 99m Tc-ANC) was prepared using stannous chloride as reducing agent, which produced yield above 90% at ph 4 at room temperature within 1-5 min as reaction time. The labeled drug was stable for more than 8 h post labeling. Biodistribution study of 99m Tc-ANC in normal mice reflected that its uptake was increased in organ of high proliferation like stomach. In solid tumor bearing mice 99m Tc-ANC was incorporated rapidly in tumor site and declined slowly, while it was declined rapidly from other tissues. Biodistribution of 99m Tc-ANC in solid tumor presented a possible model for imaging of tumors.

Mechanisms of chemoresistance to alkylating agents in malignant glioma.

Science.gov (United States)

Sarkaria, Jann N; Kitange, Gaspar J; James, C David; Plummer, Ruth; Calvert, Hilary; Weller, Michael; Wick, Wolfgang

2008-05-15

Intrinsic or acquired chemoresistance to alkylating agents is a major cause of treatment failure in patients with malignant brain tumors. Alkylating agents, the mainstay of treatment for brain tumors, damage the DNA and induce apoptosis, but the cytotoxic activity of these agents is dependent on DNA repair pathways. For example, O6-methylguanine DNA adducts can cause double-strand breaks, but this is dependent on a functional mismatch repair pathway. Thus, tumor cell lines deficient in mismatch repair are resistant to alkylating agents. Perhaps the most important mechanism of resistance to alkylating agents is the DNA repair enzyme O6-methylguanine methyltransferase, which can eliminate the cytotoxic O6-methylguanine DNA adduct before it causes harm. Another mechanism of resistance to alkylating agents is the base excision repair (BER) pathway. Consequently, efforts are ongoing to develop effective inhibitors of BER. Poly(ADP-ribose)polymerase plays a pivotal role in BER and is an important therapeutic target. Developing effective strategies to overcome chemoresistance requires the identification of reliable preclinical models that recapitulate human disease and which can be used to facilitate drug development. This article describes the diverse mechanisms of chemoresistance operating in malignant glioma and efforts to develop reliable preclinical models and novel pharmacologic approaches to overcome resistance to alkylating agents.

Mesenchymal Stem Cells as New Therapeutic Agents for the Treatment of Primary Biliary Cholangitis

Directory of Open Access Journals (Sweden)

Aleksandar Arsenijevic

2017-01-01

Full Text Available Primary biliary cholangitis (PBC is a chronic autoimmune cholestatic liver disease characterized by the progressive destruction of small- and medium-sized intrahepatic bile ducts with resultant cholestasis and progressive fibrosis. Ursodeoxycholic acid and obethicholic acid are the only agents approved by the US Food and Drug Administration (FDA for the treatment of PBC. However, for patients with advanced, end-stage PBC, liver transplantation is still the most effective treatment. Accordingly, the alternative approaches, such as mesenchymal stem cell (MSC transplantation, have been suggested as an effective alternative therapy for these patients. Due to their immunomodulatory characteristics, MSCs are considered as promising therapeutic agents for the therapy of autoimmune liver diseases, including PBC. In this review, we have summarized the therapeutic potential of MSCs for the treatment of these diseases, emphasizing molecular and cellular mechanisms responsible for MSC-based effects in an animal model of PBC and therapeutic potential observed in recently conducted clinical trials. We have also presented several outstanding problems including safety issues regarding unwanted differentiation of transplanted MSCs which limit their therapeutic use. Efficient and safe MSC-based therapy for PBC remains a challenging issue that requires continuous cooperation between clinicians, researchers, and patients.

Tumor Therapeutics Work as Stress Inducers to Enhance Tumor Sensitivity to Natural Killer (NK) Cell Cytolysis by Up-regulating NKp30 Ligand B7-H6.

Science.gov (United States)

Cao, Guoshuai; Wang, Jian; Zheng, Xiaodong; Wei, Haiming; Tian, Zhigang; Sun, Rui

2015-12-11

Immune cells are believed to participate in initiating anti-tumor effects during regular tumor therapy such as chemotherapy, radiation, hyperthermia, and cytokine injection. One of the mechanisms underlying this process is the expression of so-called stress-inducible immunostimulating ligands. Although the activating receptor NKG2D has been proven to play roles in tumor therapy through targeting its ligands, the role of NKp30, another key activating receptor, is seldom addressed. In this study, we found that the NKp30 ligand B7-H6 was widely expressed in tumor cells and closely correlated to their susceptibility to NK cell lysis. Further studies showed that treatment of tumor cells with almost all standard tumor therapeutics, including chemotherapy (cisplatin, 5-fluorouracil), radiation therapy, non-lethal heat shock, and cytokine therapy (TNF-α), could up-regulate the expression of B7-H6 in tumor cells and enhance tumor sensitivity to NK cell cytolysis. B7-H6 shRNA treatment effectively dampened sensitization of tumor cells to NK-mediated lysis. Our study not only reveals the possibility that tumor therapeutics work as stress inducers to enhance tumor sensitivity to NK cell cytolysis but also suggests that B7-H6 could be a potential target for tumor therapy in the future. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

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

The sensitivity testing of Wilms' tumors to cytostatic agents with an autoradiographic in vitro short-term test

International Nuclear Information System (INIS)

Willnow, U.

1984-01-01

Sensitivity of 15 Wilms' tumors in children was tested towards cytostatic agents in vitro by means of an autoradiographic short-term test. Sensitivity was measured as the magnitude of the inhibition of 3 H-thymidine or 3 H-uridine incorporation. The test was performed with Adriamycin, Actinomycin D, Daunomycin, Bleomycin, Cyclophosphamide, Ifosfamide, Trenimon, and Arabinosylcytosine. None of the tumors is resistant to all substances, they are responsive against 2 or more drugs. The most effective drugs tested are Adriamycin, Actinomycin D and Cyclophosphamide. The tumors show a marked individual sensitivity pattern. This behavior is explained mainly by the usually high proliferative activity of Wilms' tumors. The possibilities and limits of long-term and short-term methods for sensitivity testing are discussed critically. For the evaluation of the results of in vitro testing and in vivo effectiveness the close correlation should be considered between the type of cytostatic agent and proliferation kinetics of the tumor, cytostatic agent and effect on tumor metabolism as well as the effect of the cytostatics and the nucleic acid precursors used for the short-term test. Despite the methodological limitations preclinical testing should be preferred to unselected chemotherapy. (author)

Potential for tumor therapy with tritiated tetracycline. Summary evaluation. [Animal tests

Energy Technology Data Exchange (ETDEWEB)

Davis, R.C.; Wood, P.; Wood, L.L.; Mendelsohn, M.L.

1976-10-26

Reports of tetracycline accumulation in human and animal tumors have led a number of investigators to postulate that this drug, if radio-labeled, might have potential as a therapeutic or diagnostic agent. This paper describes attempts to investigate this potential for tritiated tetracycling. The therapeutic studies demonstrated that while a significant reduction in the growth rates of transplanted tumors could be obtained by the administration of heavy doses of TTC relative to uninjected controls, similar reductions were observed in the growth rates of tumors in animals receiving unlabeled TC. In the localization studies in rodents, the concentrations of TTC in normal tissues and tumors were compared and were correlated with the corresponding concentrations of /sup 14/C-thymidine, a measure of proliferative activity.

Advancing bioluminescence imaging technology for the evaluation of anticancer agents in the MDA-MB-435-HAL-Luc mammary fat pad and subrenal capsule tumor models.

Science.gov (United States)

Zhang, Cathy; Yan, Zhengming; Arango, Maria E; Painter, Cory L; Anderes, Kenna

2009-01-01

Tumors grafted s.c. or under the mammary fat pad (MFP) rarely develop efficient metastasis. By applying bioluminescence imaging (BLI) technology, the MDA-MB-435-HAL-Luc subrenal capsule (SRC) model was compared with the MFP model for disease progression, metastatic potential, and response to therapy. The luciferase-expressing MDA-MB-435-HAL-Luc cell line was used in both MFP and SRC models. BLI technology allowed longitudinal assessment of disease progression and the therapeutic response to PD-0332991, Avastin, and docetaxel. Immunohistochemical analysis of Ki67 and CD31 staining in the primary tumors was compared in these models. Caliper measurement was used in the MFP model to validate the BLI quantification of primary tumors. The primary tumors in MDA-MB-435-HAL-Luc MFP and SRC models displayed comparable growth rates and vascularity. However, tumor-bearing mice in the SRC model developed lung metastases much earlier (4 weeks) than in the MFP model (>7 weeks), and the metastatic progression contributed significantly to the survival time. In the MFP model, BLI and caliper measurements were comparable for quantifying palpable tumors, but BLI offered an advantage for detecting the primary tumors that fell below a palpable threshold and for visualizing metastases. In the SRC model, BLI allowed longitudinal assessment of the antitumor and antimetastatic effects of PD-0332991, Avastin, and docetaxel, and the results correlated with the survival benefits of these agents. The MDA-MB-435-HAL-Luc SRC model and the MFP model displayed differences in disease progression. BLI is an innovative approach for developing animal models and creates opportunities for improving preclinical evaluations of anticancer agents.

Connective tissue growth factor as a novel therapeutic target in high grade serous ovarian cancer.

Science.gov (United States)

Moran-Jones, Kim; Gloss, Brian S; Murali, Rajmohan; Chang, David K; Colvin, Emily K; Jones, Marc D; Yuen, Samuel; Howell, Viive M; Brown, Laura M; Wong, Carol W; Spong, Suzanne M; Scarlett, Christopher J; Hacker, Neville F; Ghosh, Sue; Mok, Samuel C; Birrer, Michael J; Samimi, Goli

2015-12-29

Ovarian cancer is the most common cause of death among women with gynecologic cancer. We examined molecular profiles of fibroblasts from normal ovary and high-grade serous ovarian tumors to identify novel therapeutic targets involved in tumor progression. We identified 2,300 genes that are significantly differentially expressed in tumor-associated fibroblasts. Fibroblast expression of one of these genes, connective tissue growth factor (CTGF), was confirmed by immunohistochemistry. CTGF protein expression in ovarian tumor fibroblasts significantly correlated with gene expression levels. CTGF is a secreted component of the tumor microenvironment and is being pursued as a therapeutic target in pancreatic cancer. We examined its effect in in vitro and ex vivo ovarian cancer models, and examined associations between CTGF expression and clinico-pathologic characteristics in patients. CTGF promotes migration and peritoneal adhesion of ovarian cancer cells. These effects are abrogated by FG-3019, a human monoclonal antibody against CTGF, currently under clinical investigation as a therapeutic agent. Immunohistochemical analyses of high-grade serous ovarian tumors reveal that the highest level of tumor stromal CTGF expression was correlated with the poorest prognosis. Our findings identify CTGF as a promoter of peritoneal adhesion, likely to mediate metastasis, and a potential therapeutic target in high-grade serous ovarian cancer. These results warrant further studies into the therapeutic efficacy of FG-3019 in high-grade serous ovarian cancer.

Hyaluronic acid-functionalized single-walled carbon nanotubes as tumor-targeting MRI contrast agent

Directory of Open Access Journals (Sweden)

Hou L

2015-07-01

Full Text Available Lin Hou,* Huijuan Zhang,* Yating Wang, Lili Wang, Xiaomin Yang, Zhenzhong ZhangSchool of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, People’s Republic of China*These authors contributed equally to this workAbstract: A tumor-targeting carrier, hyaluronic acid (HA-functionalized single-walled carbon nanotubes (SWCNTs, was explored to deliver magnetic resonance imaging (MRI contrast agents (CAs targeting to the tumor cells specifically. In this system, HA surface modification for SWCNTs was simply accomplished by amidation process and could make this nanomaterial highly hydrophilic. Cellular uptake was performed to evaluate the intracellular transport capabilities of HA-SWCNTs for tumor cells and the uptake rank was HA-SWCNTs> SWCNTs owing to the presence of HA, which was also evidenced by flow cytometry. The safety evaluation of this MRI CAs was investigated in vitro and in vivo. It revealed that HA-SWCNTs could stand as a biocompatible nanocarrier and gadolinium (Gd/HA-SWCNTs demonstrated almost no toxicity compared with free GdCl3. Moreover, GdCl3 bearing HA-SWCNTs could significantly increase the circulation time for MRI. Finally, to investigate the MRI contrast enhancing capabilities of Gd/HA-SWCNTs, T1-weighted MR images of tumor-bearing mice were acquired. The results suggested Gd/HA-SWCNTs had the highest tumor-targeting efficiency and T1-relaxivity enhancement, indicating HA-SWCNTs could be developed as a tumor-targeting carrier to deliver the CAs, GdCl3, for the identifiable diagnosis of tumor.Keywords: gadolinium, magnetic resonance, SWCNTs, hyaluronic acid, contrast agent

Hypoxia-Inducible Factors: Mediators of Cancer Progression; Prognostic and Therapeutic Targets in Soft Tissue Sarcomas

International Nuclear Information System (INIS)

Sadri, Navid; Zhang, Paul J.

2013-01-01

Soft-tissue sarcomas remain aggressive tumors that result in death in greater than a third of patients due to either loco-regional recurrence or distant metastasis. Surgical resection remains the main choice of treatment for soft tissue sarcomas with pre- and/or post-operational radiation and neoadjuvant chemotherapy employed in more advanced stage disease. However, in recent decades, there has been little progress in the average five-year survival for the majority of patients with high-grade soft tissue sarcomas, highlighting the need for improved targeted therapeutic agents. Clinical and preclinical studies demonstrate that tumor hypoxia and up-regulation of hypoxia-inducible factors (HIFs) is associated with decreased survival, increased metastasis, and resistance to therapy in soft tissue sarcomas. HIF-mediated gene expression regulates many critical aspects of tumor biology, including cell survival, metabolic programming, angiogenesis, metastasis, and therapy resistance. In this review, we discuss HIFs and HIF-mediated genes as potential prognostic markers and therapeutic targets in sarcomas. Many pharmacological agents targeting hypoxia-related pathways are in development that may hold therapeutic potential for treating both primary and metastatic sarcomas that demonstrate increased HIF expression

Ocular complication with therapeutic irradiation of malignant tumor in the maxilla

International Nuclear Information System (INIS)

Takahashi, Hisashi; Konno, Akiyoshi

1983-01-01

This paper describes the ocular complications of 33 cases who had undergone therapeutic irradiation for malignant tumor in the maxilla. Irradiation was performed with megavoltage x-ray of 6000 rads or more. Among the 18 patients with intraorbital infiltration of the tumor, 8 showed severe ocular lesion. In contrast, only 3 among the 15 patients without intraorbital infiltration showed severe lesions. Retinopathy was observed in 13 patients. Funduscopic findings and fluorescein angiograms were similar to those in diabetic retinopathy. One case of retinopathy with neovascular change was treated with panretinal argon laser photocoagulation; however, it was not successful. Most of the 7 glaucoma patients had neovascular glaucoma. They had the worst prognosis. (author)

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...

Fabrication and evaluation of tumor-targeted positive MRI contrast agent based on ultrasmall MnO nanoparticles.

Science.gov (United States)

Huang, Haitao; Yue, Tao; Xu, Ke; Golzarian, Jafar; Yu, Jiahui; Huang, Jin

2015-07-01

Gd(III) chelate is currently used as positive magnetic resonance imaging (MRI) contrast agent in clinical diagnosis, but generally induces the risk of nephrogenic systemic fibrosis (NSF) due to the dissociated Gd(3+) from Gd(III) chelates. To develop a novel positive MRI contrast agent with low toxicity and high sensitivity, ultrasmall MnO nanoparticles were PEGylated via catechol-Mn chelation and conjugated with cRGD as active targeting function to tumor. Particularly, the MnO nanoparticles with a size of ca. 5nm were modified by α,β-poly(aspartic acid)-based graft polymer containing PEG and DOPA moieties and, meanwhile, conjugated with cRGD to produce the contrast agent with a size of ca. 100nm and a longitudinal relaxivity (r1) of 10.2mM(-1)S(-1). Such nanoscaled contrast agent integrated passive- and active-targeting function to tumor, and its efficient accumulation behavior in tumor was verified by in vivo distribution study. At the same time, the PEG moiety played a role of hydrophilic coating to improve the biocompatibility and stability under storing and physiological conditions, and especially might guarantee enough circulation time in blood. Moreover, in vivo MRI revealed a good and long-term effect of enhancing MRI signal for as-fabricated contrast agent while cell viability assay proved its acceptable cytotoxicity for MRI application. On the whole, the as-fabricated PEGylated and cRGD-functionalized contrast agent based on ultrasmall MnO nanoparticles showed a great potential to the T1-weighted MRI diagnosis of tumor. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Nanodiamond-Manganese dual mode MRI contrast agents for enhanced liver tumor detection.

Science.gov (United States)

Hou, Weixin; Toh, Tan Boon; Abdullah, Lissa Nurrul; Yvonne, Tay Wei Zheng; Lee, Kuan J; Guenther, Ilonka; Chow, Edward Kai-Hua

2017-04-01

Contrast agent-enhanced magnetic resonance (MR) imaging is critical for the diagnosis and monitoring of a number of diseases, including cancer. Certain clinical applications, including the detection of liver tumors, rely on both T1 and T2-weighted images even though contrast agent-enhanced MR imaging is not always reliable. Thus, there is a need for improved dual mode contrast agents with enhanced sensitivity. We report the development of a nanodiamond-manganese dual mode contrast agent that enhanced both T1 and T2-weighted MR imaging. Conjugation of manganese to nanodiamonds resulted in improved longitudinal and transverse relaxivity efficacy over unmodified MnCl 2 as well as clinical contrast agents. Following intravenous administration, nanodiamond-manganese complexes outperformed current clinical contrast agents in an orthotopic liver cancer mouse model while also reducing blood serum concentration of toxic free Mn 2+ ions. Thus, nanodiamond-manganese complexes may serve as more effective dual mode MRI contrast agent, particularly in cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

Down-regulation of DNA mismatch repair proteins in human and murine tumor spheroids: implications for multicellular resistance to alkylating agents.

Science.gov (United States)

Francia, Giulio; Green, Shane K; Bocci, Guido; Man, Shan; Emmenegger, Urban; Ebos, John M L; Weinerman, Adina; Shaked, Yuval; Kerbel, Robert S

2005-10-01

Similar to other anticancer agents, intrinsic or acquired resistance to DNA-damaging chemotherapeutics is a major obstacle for cancer therapy. Current strategies aimed at overcoming this problem are mostly based on the premise that tumor cells acquire heritable genetic mutations that contribute to drug resistance. Here, we present evidence for an epigenetic, tumor cell adhesion-mediated, and reversible form of drug resistance that is associated with a reduction of DNA mismatch repair proteins PMS2 and/or MLH1 as well as other members of this DNA repair process. Growth of human breast cancer, human melanoma, and murine EMT-6 breast cancer cell lines as multicellular spheroids in vitro, which is associated with increased resistance to many chemotherapeutic drugs, including alkylating agents, is shown to lead to a reproducible down-regulation of PMS2, MLH1, or, in some cases, both as well as MHS6, MSH3, and MSH2. The observed down-regulation is in part reversible by treatment of tumor spheroids with the DNA-demethylating agent, 5-azacytidine. Thus, treatment of EMT-6 mouse mammary carcinoma spheroids with 5-azacytidine resulted in reduced and/or disrupted cell-cell adhesion, which in turn sensitized tumor spheroids to cisplatin-mediated killing in vitro. Our results suggest that antiadhesive agents might sensitize tumor spheroids to alkylating agents in part by reversing or preventing reduced DNA mismatch repair activity and that the chemosensitization properties of 5-azacytidine may conceivably reflect its role as a potential antiadhesive agent as well as reversal agent for MLH1 gene silencing in human tumors.

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.

Nonviral gene therapy in vivo with PAM-RG4/apoptin as a potential brain tumor therapeutic.

Science.gov (United States)

An, Songhie; Nam, Kihoon; Choi, Sunghyun; Bai, Cheng Z; Lee, Yan; Park, Jong-Sang

2013-01-01

Glioma is still one of the most complicated forms of brain tumor to remove completely due to its location and the lack of an efficient means to specifically eliminate tumor cells. For these reasons, this study has examined the effectiveness of a nonviral gene therapy approach utilizing a tumor-selective killer gene on a brain tumor xenograft model. The therapeutic apoptin gene was recombined into the JDK plasmid and delivered into human brain tumor cells (U87MG) by using a polyamidoamine dendrimer with an arginine surface (PAM-RG4). Studies in vitro showed that the PAM-RG4/apoptin plasmid polyplex exhibited a particularly high transfection activity of .40%. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, 4',6-Diamidino-2-phenylindole (DAPI) TUNEL assay, DAPI staining, and caspase-3 activity assay verified that the tumor cells had undergone apoptosis induced by apoptin. For in vivo studies, the polyplex was injected into tumors, which were induced by injecting U87MG cells intradermally into nude mice. Based on hematoxylin and eosin staining, epidermal growth factor receptor immunohistochemistry results and tumor volume measurement results, tumor growth was effectively inhibited and no specific edema, irritation, or other harm to the skin was observed after polyplex injection. The in vivo expression of apoptin and the induction of apoptosis were verified by reverse-transcription polymerase chain reaction analysis, TUNEL assay, and DAPI staining. The PAM-RG4/apoptin gene polyplex is a strong candidate for brain tumor therapeutics because of the synergistic effect of the carrier's high transfection efficiency (35%-40%) in glioma cells and the selective apoptosis-inducing activity of apoptin in tumor cells.

The antioxidant paradox: what are antioxidants and how should they be used in a therapeutic context for cancer.

Science.gov (United States)

Bonner, Michael Y; Arbiser, Jack L

2014-01-01

So-called antioxidants have yet to make a clinical impact on the treatment of human cancer. The reasons for this failure are several. First, many agents that are called antioxidants are truly antioxidants at a given dose, but this dose may not have been given in clinical trials. Second, many agents are not antioxidants at all. Third, not all tumors use reactive oxygen as a signaling mechanism. Finally, reactive oxygen inhibition is often insufficient to kill or regress a tumor cell by itself, but requires sequential introduction of a therapeutic agent for maximal effect. We hope to provide a framework for the logical use of these agents in cancer.

Peptide-Mediated Liposomal Drug Delivery System Targeting Tumor Blood Vessels in Anticancer Therapy

Directory of Open Access Journals (Sweden)

Han-Chung Wu

2010-01-01

Full Text Available Solid tumors are known to recruit new blood vessels to support their growth. Therefore, unique molecules expressed on tumor endothelial cells can function as targets for the antiangiogenic therapy of cancer. Current efforts are focusing on developing therapeutic agents capable of specifically targeting cancer cells and tumor-associated microenvironments including tumor blood vessels. These therapies hold the promise of high efficacy and low toxicity. One recognized strategy for improving the therapeutic effectiveness of conventional chemotherapeutics is to encapsulate anticancer drugs into targeting liposomes that bind to the cell surface receptors expressed on tumor-associated endothelial cells. These anti-angiogenic drug delivery systems could be used to target both tumor blood vessels as well as the tumor cells, themselves. This article reviews the mechanisms and advantages of various present and potential methods using peptide-conjugated liposomes to specifically destroy tumor blood vessels in anticancer therapy.

Matricellular proteins in drug delivery: Therapeutic targets, active agents, and therapeutic localization.

Science.gov (United States)

Sawyer, Andrew J; Kyriakides, Themis R

2016-02-01

Extracellular matrix is composed of a complex array of molecules that together provide structural and functional support to cells. These properties are mainly mediated by the activity of collagenous and elastic fibers, proteoglycans, and proteins such as fibronectin and laminin. ECM composition is tissue-specific and could include matricellular proteins whose primary role is to modulate cell-matrix interactions. In adults, matricellular proteins are primarily expressed during injury, inflammation and disease. Particularly, they are closely associated with the progression and prognosis of cardiovascular and fibrotic diseases, and cancer. This review aims to provide an overview of the potential use of matricellular proteins in drug delivery including the generation of therapeutic agents based on the properties and structures of these proteins as well as their utility as biomarkers for specific diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

Valine-based biphenylsulphonamide matrix metalloproteinase inhibitors as tumor imaging agents

Energy Technology Data Exchange (ETDEWEB)

Oltenfreiter, Ruth [Faculty of Pharmaceutical Sciences, Department of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium)]. E-mail: ruth.oltenfreiter@ugent.be; Staelens, Ludovicus [Faculty of Pharmaceutical Sciences, Department of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium); Kersemans, Veerle [Faculty of Pharmaceutical Sciences, Department of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium); Cornelissen, Bart [Faculty of Pharmaceutical Sciences, Department of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium); Frankenne, Francis [Laboratory of Tumor and Developmental Biology, University of Liege, Sart-Tilman, Liege (Belgium); Foidart, Jean-Michel [Laboratory of Tumor and Developmental Biology, University of Liege, Sart-Tilman, Liege (Belgium); Wiele, Christophe van de [Division of Nuclear Medicine, Gent University Hospital, De Pintelaan 185, 9000 Gent (Belgium); Slegers, Guido [Faculty of Pharmaceutical Sciences, Department of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium)

2006-06-15

Among matrix metalloproteinases (MMPs), the subfamily of gelatinases (MMP-2, MMP-9) is of particular interest due to their ability to degrade type IV collagen and other non-fibrillar collagen domains and proteins such as fibronectin and laminin. Whilst malignant cells often over-express various MMPs, the gelatinases have been most consistently detected in malignant tissues and associated with tumor growth, metastatic potential and angiogenesis. Radiosynthesis of carboxylic (1') and hydroxamic (2') MMPIs resulted in radiochemical yields of 70+/-5% (n=6) and 60+/-5% (n=4), respectively. Evaluation in A549-inoculated athymic mice showed a tumor uptake of 2.0+/-0.7%ID/g (3h p.i.), a tumor/blood ratio of 0.5 and a tumor/muscle ratio of 4.6 at 48hp.i. for 1'. For compound 2' a tumor uptake of 0.7+/-0.2%ID/g (3hp.i.), a tumor/blood ratio of 1.2 and a tumor/muscle ratio of 1.8 at 24hp.i. were observed. HPLC analysis of the blood (plasma) showed no dehalogenation or other metabolites of 1' 2hp.i. For compound 2', 65.4% of intact compound was found in the blood (plasma) and one polar metabolite (31%) was detected whereas in the tumor 91.8% of the accumulated activity was caused by intact compound and only 8.1% by the metabolite. Planar imaging, using a Toshiba GCA-9300A/hg SPECT camera, showed that tumor tissue could be visualized and that image quality improved by decreasing specific activity resulting in lower liver uptake, indicating some degree of saturable binding in the liver. In vivo evaluation of these radioiodinated carboxylic and hydroxamic MMP inhibitor tracers revealed that MMP inhibitors could have potential as tumor imaging agents, but that further research is necessary.

Valine-based biphenylsulphonamide matrix metalloproteinase inhibitors as tumor imaging agents

International Nuclear Information System (INIS)

Oltenfreiter, Ruth; Staelens, Ludovicus; Kersemans, Veerle; Cornelissen, Bart; Frankenne, Francis; Foidart, Jean-Michel; Wiele, Christophe van de; Slegers, Guido

2006-01-01

Among matrix metalloproteinases (MMPs), the subfamily of gelatinases (MMP-2, MMP-9) is of particular interest due to their ability to degrade type IV collagen and other non-fibrillar collagen domains and proteins such as fibronectin and laminin. Whilst malignant cells often over-express various MMPs, the gelatinases have been most consistently detected in malignant tissues and associated with tumor growth, metastatic potential and angiogenesis. Radiosynthesis of carboxylic (1') and hydroxamic (2') MMPIs resulted in radiochemical yields of 70+/-5% (n=6) and 60+/-5% (n=4), respectively. Evaluation in A549-inoculated athymic mice showed a tumor uptake of 2.0+/-0.7%ID/g (3h p.i.), a tumor/blood ratio of 0.5 and a tumor/muscle ratio of 4.6 at 48hp.i. for 1'. For compound 2' a tumor uptake of 0.7+/-0.2%ID/g (3hp.i.), a tumor/blood ratio of 1.2 and a tumor/muscle ratio of 1.8 at 24hp.i. were observed. HPLC analysis of the blood (plasma) showed no dehalogenation or other metabolites of 1' 2hp.i. For compound 2', 65.4% of intact compound was found in the blood (plasma) and one polar metabolite (31%) was detected whereas in the tumor 91.8% of the accumulated activity was caused by intact compound and only 8.1% by the metabolite. Planar imaging, using a Toshiba GCA-9300A/hg SPECT camera, showed that tumor tissue could be visualized and that image quality improved by decreasing specific activity resulting in lower liver uptake, indicating some degree of saturable binding in the liver. In vivo evaluation of these radioiodinated carboxylic and hydroxamic MMP inhibitor tracers revealed that MMP inhibitors could have potential as tumor imaging agents, but that further research is necessary

Preparation of 188 Re-lanreotide as a potential tumor therapeutic agent

International Nuclear Information System (INIS)

Bai Hongsheng; Jin Xiaohai; Fan Hongqiang; Jia Bing; Wang Yuqing; Lu Weiwei

2001-01-01

Radiolabeled peptides hold unlimited potential in diagnostic applications and therapy of malignant tumor. Somatostatin analogue peptide (Lanreotide) is labeled directly with 188 Re via the mixture of citrate and tartrate. The influences of reaction conditions such as pH, temperature, amount of stannous chloride, Lanreotide quantity, reaction time on labeling yield are investigated in detail. At the same time, the stability in vitro, quality control and animal test are evaluated. The experimental results show that Lanreotide reacts with 188 Re for 40 min at pH 2 - 3 and 60 degree C, the labeling yield is at range of 88% - 94%. After purification of 188 Re-Lanreotide with Sep-Pak C 18 reverse phase extraction cartridge, the radiochemical purity (RP) is more than 95%. 188 Re-Lanreotide is eliminated rapidly from the blood and is excreted through liver, the uptake of lung and intestine is high

Targeted Therapy of Cancer Using Photodynamic Therapy in Combination with Multi-faceted Anti-Tumor Modalities

Directory of Open Access Journals (Sweden)

Malini Olivo

2010-05-01

Full Text Available Photodynamic therapy (PDT has emerged as one of the important therapeutic options in the management of cancer and other diseases. PDT involves a tumor-localized photosensitizer (PS, which when appropriately illuminated by visible light converts oxygen into cytotoxic reactive oxygen species (ROS, that attack key structural entities within the targeted cells, ultimately resulting in necrosis or apoptosis. Though PDT is a selective modality, it can be further enhanced by combining other targeted therapeutic strategies that include the use of synthetic peptides and nanoparticles for selective delivery of photosensitizers. Another potentially promising strategy is the application of targeted therapeutics that exploit a myriad of critical pathways involved in tumorigenesis and metastasis. Vascular disrupting agents that eradicate tumor vasculature during PDT and anti-angiogenic agents that targets specific molecular pathways and prevent the formation of new blood vessels are novel therapeutic approaches that have been shown to improve treatment outcome. In addition to the well-documented mechanisms of direct cell killing and damage to the tumor vasculature, PDT can also activate the body’s immune response against tumors. Numerous pre-clinical studies and clinical observations have demonstrated the immuno-stimulatory capability of PDT. Herein, we aim to integrate the most important findings with regard to the combination of PDT and other novel targeted therapy approaches, detailing its potential in cancer photomedicine.

Super enhanced permeability and retention (SUPR) effects in tumors following near infrared photoimmunotherapy

Science.gov (United States)

Kobayashi, Hisataka; Choyke, Peter L.

2016-06-01

To date, the delivery of nano-sized therapeutic agents to cancers largely relies on enhanced permeability and retention (EPR) effects that are caused by the leaky nature of cancer vasculature. However, nano-sized agents delivered in this way have demonstrated limited success in oncology due to the relatively small magnitude of the EPR effect. For achieving superior delivery of nano-sized agents, super-enhanced permeability and retention (SUPR) effects are needed. Near infrared photo-immunotherapy (NIR-PIT) is a recently reported therapy that treats tumors with light therapy and subsequently causes an increase in nano-drug delivery up to 24-fold compared with untreated tumors in which only the EPR effect is present. SUPR effects could enhance delivery into tumor beds of a wide variety of nano-sized agents including particles, antibodies, and protein binding small molecular agents. Therefore, taking advantage of the SUPR effects after NIR-PIT may be a promising avenue to utilize a wide variety of nano-drugs in a highly effective manner.

Repeated tumor pO2 measurements by multi-site EPR oximetry as a prognostic marker for enhanced therapeutic efficacy of fractionated radiotherapy

International Nuclear Information System (INIS)

Hou Huagang; Lariviere, Jean P.; Demidenko, Eugene; Gladstone, David; Swartz, Harold; Khan, Nadeem

2009-01-01

Purpose: To investigate the temporal effects of single or fractionated radiotherapy on subcutaneous RIF-1 tumor pO 2 and to determine the therapeutic outcomes when the timing of fractionations is guided by tumor pO 2 . Methods: The time-course of the tumor pO 2 changes was followed by multi-site electron paramagnetic resonance (EPR) oximetry. The tumors were treated with single 10, 20, and 10 Gy x 2 doses, and the tumor pO 2 was measured repeatedly for six consecutive days. In the 10 Gy x 2 group, the second dose of 10 Gy was delivered at a time when the tumors were either relatively oxygenated or hypoxic. The changes in tumor volumes were followed for nine days to determine the therapeutic outcomes. Results: A significant increase in tumor pO 2 was observed at 24 h post 10 Gy, while 20 Gy resulted in a significant increase in tumor pO 2 at 72-120 h post irradiation. The tumors irradiated with a second dose of 10 Gy at 24 h, when the tumors were oxygenated, had a significant increase in tumor doubling times (DTs), as compared to tumors treated at 48 h when they were hypoxic (p 2 repeatedly during fractionated schemes to optimize radiotherapeutic outcome. This technique could also be used to identify responsive and non-responsive tumors, which will facilitate the design of other therapeutic approaches for non-responsive tumors at early time points during the course of therapy.

O6-Methylguanine DNA Methyltransferase Status Does Not Predict Response or Resistance to Alkylating Agents in Well-Differentiated Pancreatic Neuroendocrine Tumors.

Science.gov (United States)

Raj, Nitya; Klimstra, David S; Horvat, Natally; Zhang, Liying; Chou, Joanne F; Capanu, Marinela; Basturk, Olca; Do, Richard Kinh Gian; Allen, Peter J; Reidy-Lagunes, Diane

2017-07-01

Alkylating agents have activity in well-differentiated pancreatic neuroendocrine tumors (WD panNETs). In glioblastoma multiforme, decreased activity of O-methylguanine DNA methyltransferase (MGMT) predicts response; in panNETs, MGMT relevance is unknown. We identified patients with WD panNETs treated with alkylating agents, determined best overall response by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1, and performed MGMT activity testing. Fifty-six patients were identified; 26 (46%) of the 56 patients experienced partial response, 24 (43%) of 56 experienced stable disease, and 6 (11%) of 56 experienced progression of disease. O-methylguanine DNA methyltransferase status was available for 36 tumors. For tumors with partial response, 10 (67%) of 15 were MGMT deficient, and 5 (33%) of 15 were MGMT intact. For tumors with stable disease, 7 (47%) of 15 were MGMT deficient, and 8 (53%) of 15 were MGMT intact. For tumors with progression of disease, 3 (50%) of 6 were MGMT deficient, and 3 (50%) of 6 were MGMT intact. We observed response and resistance to alkylating agents in MGMT-deficient and MGMT-intact tumors. O-methylguanine DNA methyltransferase status should not guide alkylating agent therapy in WD panNETs.

Review of therapeutic agents for burns pruritus and protocols for management in adult and paediatric patients using the GRADE classification

Directory of Open Access Journals (Sweden)

Goutos Ioannis

2010-10-01

Full Text Available To review the current evidence on therapeutic agents for burns pruritus and use the Grading of Recommendations, Assessment, Development and Evaluation (GRADE classification to propose therapeutic protocols for adult and paediatric patients. All published interventions for burns pruritus were analysed by a multidisciplinary panel of burns specialists following the GRADE classification to rate individual agents. Following the collation of results and panel discussion, consensus protocols are presented. Twenty-three studies appraising therapeutic agents in the burns literature were identified. The majority of these studies (16 out of 23 are of an observational nature, making an evidence-based approach to defining optimal therapy not feasible. Our multidisciplinary approach employing the GRADE classification recommends the use of antihistamines (cetirizine and cimetidine and gabapentin as the first-line pharmacological agents for both adult and paediatric patients. Ondansetron and loratadine are the second-line medications in our protocols. We additionally recommend a variety of non-pharmacological adjuncts for the perusal of clinicians in order to maximise symptomatic relief in patients troubled with postburn itch. Most studies in the subject area lack sufficient statistical power to dictate a ′gold standard′ treatment agent for burns itch. We encourage clinicians to employ the GRADE system in order to delineate the most appropriate therapeutic approach for burns pruritus until further research elucidates the most efficacious interventions. This widely adopted classification empowers burns clinicians to tailor therapeutic regimens according to current evidence, patient values, risks and resource considerations in different medical environments.

Silibinin, dexamethasone, and doxycycline as potential therapeutic agents for treating vesicant-inflicted ocular injuries

International Nuclear Information System (INIS)

Tewari-Singh, Neera; Jain, Anil K.; Inturi, Swetha; Ammar, David A.; Agarwal, Chapla; Tyagi, Puneet; Kompella, Uday B.; Enzenauer, Robert W.; Petrash, J. Mark; Agarwal, Rajesh

2012-01-01

There are no effective and approved therapies against devastating ocular injuries caused by vesicating chemical agents sulfur mustard (SM) and nitrogen mustard (NM). Herein, studies were carried out in rabbit corneal cultures to establish relevant ocular injury biomarkers with NM for screening potential efficacious agents in laboratory settings. NM (100 nmol) exposure of the corneas for 2 h (cultured for 24 h), showed increases in epithelial thickness, ulceration, apoptotic cell death, epithelial detachment microbullae formation, and the levels of VEGF, cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9). Employing these biomarkers, efficacy studies were performed with agent treatments 2 h and every 4 h thereafter, for 24 h following NM exposure. Three agents were evaluated, including prescription drugs dexamethasone (0.1%; anti-inflammatory steroid) and doxycycline (100 nmol; antibiotic and MMP inhibitor) that have been studied earlier for treating vesicant-induced eye injuries. We also examined silibinin (100 μg), a non-toxic natural flavanone found to be effective in treating SM analog-induced skin injuries in our earlier studies. Treatments of doxycycline + dexamethasone, and silibinin were more effective than doxycycline or dexamethasone alone in reversing NM-induced epithelial thickening, microbullae formation, apoptotic cell death, and MMP-9 elevation. However, dexamethasone and silibinin alone were more effective in reversing NM-induced VEGF levels. Doxycycline, dexamethasone and silibinin were all effective in reversing NM-induced COX-2 levels. Apart from therapeutic efficacy of doxycycline and dexamethasone, these results show strong multifunctional efficacy of silibinin in reversing NM-induced ocular injuries, which could help develop effective and safe therapeutics against ocular injuries by vesicants. -- Highlights: ► Established injury biomarkers in rabbit corneal culture with nitrogen mustard (NM) ► This NM model is a cost effective

Silibinin, dexamethasone, and doxycycline as potential therapeutic agents for treating vesicant-inflicted ocular injuries

Energy Technology Data Exchange (ETDEWEB)

Tewari-Singh, Neera, E-mail: Neera.Tewari-Singh@ucdenver.edu [Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045 (United States); Jain, Anil K., E-mail: Anil.Jain@ucdenver.edu [Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045 (United States); Inturi, Swetha, E-mail: Swetha.Inturi@ucdenver.edu [Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045 (United States); Ammar, David A., E-mail: David.Ammar@ucdenver.edu [Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO 80045 (United States); Agarwal, Chapla, E-mail: Chapla.Agarwal@ucdenver.edu [Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045 (United States); Tyagi, Puneet, E-mail: Puneet.Tyagi@ucdenver.edu [Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045 (United States); Kompella, Uday B., E-mail: Uday.Kompella@ucdenver.edu [Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045 (United States); Enzenauer, Robert W., E-mail: Robert.Enzenauer@ucdenver.edu [Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO 80045 (United States); Petrash, J. Mark, E-mail: Mark.Petrash@ucdenver.edu [Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO 80045 (United States); Agarwal, Rajesh, E-mail: Rajesh.Agarwal@ucdenver.edu [Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045 (United States)

2012-10-01

There are no effective and approved therapies against devastating ocular injuries caused by vesicating chemical agents sulfur mustard (SM) and nitrogen mustard (NM). Herein, studies were carried out in rabbit corneal cultures to establish relevant ocular injury biomarkers with NM for screening potential efficacious agents in laboratory settings. NM (100 nmol) exposure of the corneas for 2 h (cultured for 24 h), showed increases in epithelial thickness, ulceration, apoptotic cell death, epithelial detachment microbullae formation, and the levels of VEGF, cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9). Employing these biomarkers, efficacy studies were performed with agent treatments 2 h and every 4 h thereafter, for 24 h following NM exposure. Three agents were evaluated, including prescription drugs dexamethasone (0.1%; anti-inflammatory steroid) and doxycycline (100 nmol; antibiotic and MMP inhibitor) that have been studied earlier for treating vesicant-induced eye injuries. We also examined silibinin (100 μg), a non-toxic natural flavanone found to be effective in treating SM analog-induced skin injuries in our earlier studies. Treatments of doxycycline + dexamethasone, and silibinin were more effective than doxycycline or dexamethasone alone in reversing NM-induced epithelial thickening, microbullae formation, apoptotic cell death, and MMP-9 elevation. However, dexamethasone and silibinin alone were more effective in reversing NM-induced VEGF levels. Doxycycline, dexamethasone and silibinin were all effective in reversing NM-induced COX-2 levels. Apart from therapeutic efficacy of doxycycline and dexamethasone, these results show strong multifunctional efficacy of silibinin in reversing NM-induced ocular injuries, which could help develop effective and safe therapeutics against ocular injuries by vesicants. -- Highlights: ► Established injury biomarkers in rabbit corneal culture with nitrogen mustard (NM) ► This NM model is a cost effective

Amplification of tumor inducing putative cancer stem cells (CSCs) by vitamin A/retinol from mammary tumors

Energy Technology Data Exchange (ETDEWEB)

Sharma, Rohit B. [Department of Microbiology and Molecular Genetics, University of Pittsburgh, PA 15261 (United States); Wang, Qingde [Department of Surgery, University of Pittsburgh, PA 15261 (United States); Khillan, Jaspal S., E-mail: khillan@pitt.edu [Department of Microbiology and Molecular Genetics, University of Pittsburgh, PA 15261 (United States)

2013-07-12

Highlights: •Vitamin A supports self renewal of putative CSCs from mammary tumors. •These cells exhibit impaired retinol metabolism into retinoic acid. •CSCs from mammary tumors differentiate into mammary specific cell lineages. •The cells express mammary stem cell specific CD29 and CD49f markers. •Putative CSCs form highly metastatic tumors in NOD SCID mouse. -- Abstract: Solid tumors contain a rare population of cancer stem cells (CSCs) that are responsible for relapse and metastasis. The existence of CSC however, remains highly controversial issue. Here we present the evidence for putative CSCs from mammary tumors amplified by vitamin A/retinol signaling. The cells exhibit mammary stem cell specific CD29{sup hi}/CD49f{sup hi}/CD24{sup hi} markers, resistance to radiation and chemo therapeutic agents and form highly metastatic tumors in NOD/SCID mice. The cells exhibit indefinite self renewal as cell lines. Furthermore, the cells exhibit impaired retinol metabolism and do not express enzymes that metabolize retinol into retinoic acid. Vitamin A/retinol also amplified putative CSCs from breast cancer cell lines that form highly aggressive tumors in NOD SCID mice. The studies suggest that high purity putative CSCs can be isolated from solid tumors to establish patient specific cell lines for personalized therapeutics for pre-clinical translational applications. Characterization of CSCs will allow understanding of basic cellular and molecular pathways that are deregulated, mechanisms of tumor metastasis and evasion of therapies that has direct clinical relevance.

Functional polymers as therapeutic agents: concept to market place.

Science.gov (United States)

Dhal, Pradeep K; Polomoscanik, Steven C; Avila, Louis Z; Holmes-Farley, S Randall; Miller, Robert J

2009-11-12

Biologically active synthetic polymers have received considerable scientific interest and attention in recent years for their potential as promising novel therapeutic agents to treat human diseases. Although a significant amount of research has been carried out involving polymer-linked drugs as targeted and sustained release drug delivery systems and prodrugs, examples on bioactive polymers that exhibit intrinsic therapeutic properties are relatively less. Several appealing characteristics of synthetic polymers including high molecular weight, molecular architecture, and controlled polydispersity can all be utilized to discover a new generation of therapies. For example, high molecular weight bioactive polymers can be restricted to gastrointestinal tract, where they can selectively recognize, bind, and remove target disease causing substances from the body. The appealing features of GI tract restriction and stability in biological environment render these polymeric drugs to be devoid of systemic toxicity that are generally associated with small molecule systemic drugs. The present article highlights recent developments in the rational design and synthesis of appropriate functional polymers that have resulted in a number of promising polymer based therapies and biomaterials, including some marketed products.

Computed Tomography Imaging of Solid Tumors Using a Liposomal-Iodine Contrast Agent in Companion Dogs with Naturally Occurring Cancer.

Science.gov (United States)

Ghaghada, Ketan B; Sato, Amy F; Starosolski, Zbigniew A; Berg, John; Vail, David M

2016-01-01

Companion dogs with naturally occurring cancer serve as an important large animal model in translational research because they share strong similarities with human cancers. In this study, we investigated a long circulating liposomal-iodine contrast agent (Liposomal-I) for computed tomography (CT) imaging of solid tumors in companion dogs with naturally occurring cancer. The institutional animal ethics committees approved the study and written informed consent was obtained from all owners. Thirteen dogs (mean age 10.1 years) with a variety of masses including primary and metastatic liver tumors, sarcomas, mammary carcinoma and lung tumors, were enrolled in the study. CT imaging was performed pre-contrast and at 15 minutes and 24 hours after intravenous administration of Liposomal-I (275 mg/kg iodine dose). Conventional contrast-enhanced CT imaging was performed in a subset of dogs, 90 minutes prior to administration of Liposomal-I. Histologic or cytologic diagnosis was obtained for each dog prior to admission into the study. Liposomal-I resulted in significant (p contrast agent was demonstrated. Liposomal-I enabled visualization of primary and metastatic liver tumors. Sub-cm sized liver lesions grossly appeared as hypo-enhanced compared to the surrounding normal parenchyma with improved lesion conspicuity in the post-24 hour scan. Large liver tumors (> 1 cm) demonstrated a heterogeneous pattern of intra-tumoral signal with visibly higher signal enhancement at the post-24 hour time point. Extra-hepatic, extra-splenic tumors, including histiocytic sarcoma, anaplastic sarcoma, mammary carcinoma and lung tumors, were visualized with a heterogeneous enhancement pattern in the post-24 hour scan. The long circulating liposomal-iodine contrast agent enabled prolonged visualization of small and large tumors in companion dogs with naturally occurring cancer. The study warrants future work to assess the sensitivity and specificity of the Liposomal-I agent in various types of

Spectral imaging based in vivo model system for characterization of tumor microvessel response to vascular targeting agents

Science.gov (United States)

Wankhede, Mamta

Functional vasculature is vital for tumor growth, proliferation, and metastasis. Many tumor-specific vascular targeting agents (VTAs) aim to destroy this essential tumor vasculature to induce indirect tumor cell death via oxygen and nutrition deprivation. The tumor angiogenesis-inhibiting anti-angiogenics (AIs) and the established tumor vessel targeting vascular disrupting agents (VDAs) are the two major players in the vascular targeting field. Combination of VTAs with conventional therapies or with each other, have been shown to have additive or supra-additive effects on tumor control and treatment. Pathophysiological changes post-VTA treatment in terms of structural and vessel function changes are important parameters to characterize the treatment efficacy. Despite the abundance of information regarding these parameters acquired using various techniques, there remains a need for a quantitative, real-time, and direct observation of these phenomenon in live animals. Through this research we aspired to develop a spectral imaging based mouse tumor system for real-time in vivo microvessel structure and functional measurements for VTA characterization. A model tumor system for window chamber studies was identified, and then combinatorial effects of VDA and AI were characterized in model tumor system. (Full text of this dissertation may be available via the University of Florida Libraries web site. Please check http://www.uflib.ufl.edu/etd.html)

A stable explant culture of HER2/neu invasive carcinoma supported by alpha-Smooth Muscle Actin expressing stromal cells to evaluate therapeutic agents

Directory of Open Access Journals (Sweden)

Piechocki Marie P

2008-04-01

Full Text Available Abstract Background To gain a better understanding of the effects of therapeutic agents on the tumor microenvironment in invasive cancers, we developed a co-culture model from an invasive lobular carcinoma. Tumor cells expressing HER2/neu organize in nests surrounded by alpha-Smooth Muscle Actin (α-SMA expressing tumor stroma to resemble the morphology of an invading tumor. This co-culture, Mammary Adenocarcinoma Model (MAM-1 maintains a 1:1 ratio of HER2/neu positive tumor cells to α-SMA-reactive stromal cells and renews this configuration for over 20 passages in vitro. Methods We characterized the cellular elements of the MAM-1 model by microarray analysis, and immunocytochemistry. We developed flow cytometric assays to evaluate the relative responses of the tumor and stroma to the tyrosine kinase inhibitor, Iressa. Results The MAM-1 gene expression profile contains clusters that represent the ErbB-2 breast cancer signature and stroma-specific clusters associated with invasive breast cancers. The stability of this model and the ability to antigenically label the tumor and stromal fractions allowed us to determine the specificity of Iressa, a receptor tyrosine kinase inhibitor, for targeting the tumor cell population. Treatment resulted in a selective dose-dependent reduction in phospho-pMEK1/2 and pp44/42MAPK in tumor cells. Within 24 h the tumor cell fraction was reduced 1.9-fold while the stromal cell fraction increased >3-fold, consistent with specific reductions in phospho-pp44/42 MAPK, MEK1/2 and PCNA in tumor cells and reciprocal increases in the stromal cells. Erosion of the tumor cell nests and augmented growth of the stromal cells resembled a fibrotic response. Conclusion This model demonstrates the specificity of Iressa for HER2/neu expressing tumor cells versus the tumor associated myofibroblasts and is appropriate for delineating effects of therapy on signal transduction in the breast tumor microenvironment and improving

A stable explant culture of HER2/neu invasive carcinoma supported by alpha-Smooth Muscle Actin expressing stromal cells to evaluate therapeutic agents

International Nuclear Information System (INIS)

Piechocki, Marie P

2008-01-01

To gain a better understanding of the effects of therapeutic agents on the tumor microenvironment in invasive cancers, we developed a co-culture model from an invasive lobular carcinoma. Tumor cells expressing HER2/neu organize in nests surrounded by alpha-Smooth Muscle Actin (α-SMA) expressing tumor stroma to resemble the morphology of an invading tumor. This co-culture, Mammary Adenocarcinoma Model (MAM-1) maintains a 1:1 ratio of HER2/neu positive tumor cells to α-SMA-reactive stromal cells and renews this configuration for over 20 passages in vitro. We characterized the cellular elements of the MAM-1 model by microarray analysis, and immunocytochemistry. We developed flow cytometric assays to evaluate the relative responses of the tumor and stroma to the tyrosine kinase inhibitor, Iressa. The MAM-1 gene expression profile contains clusters that represent the ErbB-2 breast cancer signature and stroma-specific clusters associated with invasive breast cancers. The stability of this model and the ability to antigenically label the tumor and stromal fractions allowed us to determine the specificity of Iressa, a receptor tyrosine kinase inhibitor, for targeting the tumor cell population. Treatment resulted in a selective dose-dependent reduction in phospho-pMEK1/2 and pp44/42MAPK in tumor cells. Within 24 h the tumor cell fraction was reduced 1.9-fold while the stromal cell fraction increased >3-fold, consistent with specific reductions in phospho-pp44/42 MAPK, MEK1/2 and PCNA in tumor cells and reciprocal increases in the stromal cells. Erosion of the tumor cell nests and augmented growth of the stromal cells resembled a fibrotic response. This model demonstrates the specificity of Iressa for HER2/neu expressing tumor cells versus the tumor associated myofibroblasts and is appropriate for delineating effects of therapy on signal transduction in the breast tumor microenvironment and improving strategies that can dually or differentially target the tumor and stromal

Therapeutic potential and challenges of Natural killer cells in treatment of solid tumors

Directory of Open Access Journals (Sweden)

Andrea eGras Navarro

2015-04-01

Full Text Available Natural killer (NK cells are innate lymphoid cells that hold tremendous potential for effective immunotherapy for a broad range of cancers. Due to the mode of NK cell killing requiring one–to-one target engagement and site directed release of cytolytic granules, the therapeutic potential of NK cells has been most extensively explored in hematological malignancies. However, their ability to precisely kill antibody coated cells, cancer stem cells (CSCs and genotoxically altered cells, while maintaining tolerance to healthy cells makes them appealing therapeutic effectors for all cancer forms, including metastases. Due to their release of pro-inflammatory cytokines, NK cells may potently reverse the anti-inflammatory tumor microenvironment (TME and augment adaptive immune responses by promoting differentiation, activation and/ or recruitment of accessory immune cells to sites of malignancy. Nevertheless, integrated and coordinated mechanisms of subversion of NK cell activity against the tumor and its microenvironment exist. Although our understanding of the receptor ligand interactions that regulate NK cell functionality has evolved remarkably, the diversity of ligands and receptors is complex, as is their mechanistic foundations in regulating NK cell function. In this article, we review the literature and highlight how the TME manipulates the NK cell phenotypes, genotypes and tropism to evade tumor recognition and elimination. We discuss counter strategies that may be adopted to augment the efficacy of NK cell anti-tumor surveillance, the clinical trials that have been undertaken so far in solid malignancies, critically weighing the challenges and opportunities with this approach.

Biodistribution of ultra small gadolinium-based nanoparticles as theranostic agent: application to brain tumors.

Science.gov (United States)

Miladi, Imen; Duc, Géraldine Le; Kryza, David; Berniard, Aurélie; Mowat, Pierre; Roux, Stéphane; Taleb, Jacqueline; Bonazza, Pauline; Perriat, Pascal; Lux, François; Tillement, Olivier; Billotey, Claire; Janier, Marc

2013-09-01

Gadolinium-based nanoparticles are novel objects with interesting physical properties, allowing their use for diagnostic and therapeutic applications. Gadolinium-based nanoparticles were imaged following intravenous injection in healthy rats and rats grafted with 9L gliosarcoma tumors using magnetic resonance imaging and scintigraphic imaging. Quantitative biodistribution using gamma-counting of each sampled organ confirmed that these nanoparticles were rapidly cleared essentially by renal excretion. Accumulation of these nanoparticles in 9L gliosarcoma tumors implanted in the rat brain was quantitated. This passive and long-duration accumulation of gadolinium-based nanoparticles in tumor, which is related to disruption of the blood-brain barrier, is in good agreement with the use of these nanoparticles as radiosensitizers for brain tumors.

Phospholipid ether analogs for the detection of colorectal tumors.

Directory of Open Access Journals (Sweden)

Dustin A Deming

Full Text Available The treatment of localized colorectal cancer (CRC depends on resection of the primary tumor with adequate margins and sufficient lymph node sampling. A novel imaging agent that accumulates in CRCs and the associated lymph nodes is needed. Cellectar Biosciences has developed a phospholipid ether analog platform that is both diagnostic and therapeutic. CLR1502 is a near-infrared fluorescent molecule, whereas 124/131I-CLR1404 is under clinical investigation as a PET tracer/therapeutic agent imaged by SPECT. We investigated the use of CLR1502 for the detection of intestinal cancers in a murine model and 131I-CLR1404 in a patient with metastatic CRC. Mice that develop multiple intestinal tumors ranging from adenomas to locally advanced adenocarcinomas were utilized. After 96 hours post CLR1502 injection, the intestinal tumors were analyzed using a Spectrum IVIS (Perkin Elmer and a Fluobeam (Fluoptics. The intensity of the fluorescent signal was correlated with the histological characteristics for each tumor. Colon adenocarcinomas demonstrated increased accumulation of CLR1502 compared to non-invasive lesions (total radiant efficiency: 1.76×10(10 vs 3.27×10(9 respectively, p = 0.006. Metastatic mesenteric tumors and uninvolved lymph nodes were detected with CLR1502. In addition, SPECT imaging with 131I-CLR1404 was performed as part of a clinical trial in patients with advanced solid tumors. 131I-CLR1404 was shown to accumulate in metastatic tumors in a patient with colorectal adenocarcinoma. Together, these compounds might enhance our ability to properly resect CRCs through better localization of the primary tumor and improved lymph node identification as well as detect distant disease.

Solitary fibrous tumor: A center's experience and an overview of the symptomatology, the diagnostic and therapeutic procedures of this rare tumor

Directory of Open Access Journals (Sweden)

Wolfgang Hohenforst-Schmidt

2017-01-01

Full Text Available Solitary Fibrous Tumor of the Pleura (SFTP is a rare tumor of the pleura. Worldwide about 800 patients diagnosed with this oncological entity have been described in the existing literature. We report our center's 13 year experience. During this time three patients suffering from this rare disease have been treated in our department. All patients were asymptomatic and their diagnosis was initially triggered by a random finding in a routine chest x-ray. The diagnosis was set preoperatively through a needle biopsy under computer tomography (CT guidance. The tumors were resected surgically though video-assisted thoracoscopic surgery (VATS or thoracotomy. Because of the lack of specific guidelines due to the rarity of the disease a long-term, systematic follow-up was recommended and performed. Parallel an overview of the diagnostic and therapeutic procedures of the rare tumor is made.

TIE2-expressing macrophages limit the therapeutic efficacy of the vascular disrupting agent, combretastatin A4 phosphate in mice.

OpenAIRE

Welford, Abigail F.; Biziato, Daniela; Coffelt, Seth B.; Nucera, Silvia; Fisher, Matthew; Pucci, Ferdinando; Di Serio, Clelia; Naldini, Luigi; De Palma, Michele; Tozer, Gillian M.; Lewis, Claire E.

2011-01-01

Vascular-disrupting agents (VDAs) such as combretastatin A4 phosphate (CA4P) selectively disrupt blood vessels in tumors and induce tumor necrosis. However, tumors rapidly repopulate after treatment with such compounds. Here, we show that CA4P-induced vessel narrowing, hypoxia, and hemorrhagic necrosis in murine mammary tumors were accompanied by elevated tumor levels of the chemokine CXCL12 and infiltration by proangiogenic TIE2-expressing macrophages (TEMs). Inhibiting TEM recruitment to CA...

Antiangiogenic Agent Might Upgrade tumor Cell Sensitivity to Ionizing Radiation

International Nuclear Information System (INIS)

Badr, N.M.S.A.

2013-01-01

The understanding of the fundamental role of angiogenesis and metastasis in cancer growth has led to tremendous interest in research regarding its regulatory mechanisms and clinical implications in the management of cancer. The present study was conducted to evaluate the influence of the angiogenic regulators modification on the tumor growth and the cell sensitivity to ionizing radiation targeting the improvement of cancer therapeutic protocols. Accordingly, the antiangiogenic activity of apigenin and selenium was tested in vitro via MTT assay. The action of Apigenin and or Selenium was examined in vivo by using a model of solid tumor carcinoma (EAC). The growth rate of solid tumor in all experimental groups was measured by Caliper. The irradiated mice were exposed to 6.5 Gy of gamma rays. Apigenin 50 mg/kg body weight and selenium 5 μg per mice were daily administrated for 14 consecutive days after tumor volume reached 1mm 3 . The angiogenic activators TNF-α (key cytokine) in spleen, serum MMP 2 and MMP 9, liver and tumor NO, the lipid peroxidation (LPx) and angiogenic inhibitor TIMP-1 in spleen as well as, antioxidant markers (CAT, SOD, GPX) in tumor and liver tissue and DNA fragmentation in splenocytes were estimated to monitor efficacy of Apigenin and selenium in cancer treatment strategy. All parameters were determined as a time course on days 16 and 22 after tumor volume reached 1mm 3 . The using of MTT assay on EAC cells shows inhibition in EAC cell proliferation after the incubation with apigenin and /or selenium. The administration of apigenin and /or selenium to mice bearing tumor and to irradiated mice bearing tumor reduce significantly the TNF-α expression, MMP 2,9 , NO , LPx level and increased the antioxidant enzymes (GPx , SOD and CAT) activities. The DNA fragmentation and the antiangiogenic factors TIMP-1 were significantly increased when compared with their values in mice bearing tumor or in irradiated mice bearing tumor. From the results

Tumor-targeting peptides from combinatorial libraries*

Science.gov (United States)

Liu, Ruiwu; Li, Xiaocen; Xiao, Wenwu; Lam, Kit S.

2018-01-01

Cancer is one of the major and leading causes of death worldwide. Two of the greatest challenges infighting cancer are early detection and effective treatments with no or minimum side effects. Widespread use of targeted therapies and molecular imaging in clinics requires high affinity, tumor-specific agents as effective targeting vehicles to deliver therapeutics and imaging probes to the primary or metastatic tumor sites. Combinatorial libraries such as phage-display and one-bead one-compound (OBOC) peptide libraries are powerful approaches in discovering tumor-targeting peptides. This review gives an overview of different combinatorial library technologies that have been used for the discovery of tumor-targeting peptides. Examples of tumor-targeting peptides identified from each combinatorial library method will be discussed. Published tumor-targeting peptide ligands and their applications will also be summarized by the combinatorial library methods and their corresponding binding receptors. PMID:27210583

Optically enhanced blood-brain-barrier crossing of plasmonic-active nanoparticles in preclinical brain tumor animal models

Science.gov (United States)

Yuan, Hsiangkuo; Wilson, Christy M.; Li, Shuqin; Fales, Andrew M.; Liu, Yang; Grant, Gerald; Vo-Dinh, Tuan

2014-02-01

Nanotechnology provides tremendous biomedical opportunities for cancer diagnosis, imaging, and therapy. In contrast to conventional chemotherapeutic agents where their actual target delivery cannot be easily imaged, integrating imaging and therapeutic properties into one platform facilitates the understanding of pharmacokinetic profiles, and enables monitoring of the therapeutic process in each individual. Such a concept dubbed "theranostics" potentiates translational research and improves precision medicine. One particular challenging application of theranostics involves imaging and controlled delivery of nanoplatforms across blood-brain-barrier (BBB) into brain tissues. Typically, the BBB hinders paracellular flux of drug molecules into brain parenchyma. BBB disrupting agents (e.g. mannitol, focused ultrasound), however, suffer from poor spatial confinement. It has been a challenge to design a nanoplatform not only acts as a contrast agent but also improves the BBB permeation. In this study, we demonstrated the feasibility of plasmonic gold nanoparticles as both high-resolution optical contrast agent and focalized tumor BBB permeation-inducing agent. We specifically examined the microscopic distribution of nanoparticles in tumor brain animal models. We observed that most nanoparticles accumulated at the tumor periphery or perivascular spaces. Nanoparticles were present in both endothelial cells and interstitial matrices. This study also demonstrated a novel photothermal-induced BBB permeation. Fine-tuning the irradiating energy induced gentle disruption of the vascular integrity, causing short-term extravasation of nanomaterials but without hemorrhage. We conclude that our gold nanoparticles are a powerful biocompatible contrast agent capable of inducing focal BBB permeation, and therefore envision a strong potential of plasmonic gold nanoparticle in future brain tumor imaging and therapy.

The fabrication of novel nanobubble ultrasound contrast agent for potential tumor imaging

Energy Technology Data Exchange (ETDEWEB)

Xing Zhanwen; Ke Hengte; Yue Xiuli; Dai Zhifei [Nanobiotechnology Division, State Key Laboratory of Urban Water Resources and Environment, School of Sciences, Harbin Institute of Technology, Harbin 150080 (China); Wang Jinrui; Zhao Bo [Department of Ultrasonography, Peking University Third Hospital, Beijing 100083 (China); Liu Jibin, E-mail: zhifei.dai@hit.edu.cn, E-mail: ji-bin.liu@jefferson.edu [Ultrasound Research and Education Institute, Thomas Jefferson University, Philadelphia, PA 19107 (United States)

2010-04-09

Novel biocompatible nanobubbles were fabricated by ultrasonication of a mixture of Span 60 and polyoxyethylene 40 stearate (PEG40S) followed by differential centrifugation to isolate the relevant subpopulation from the parent suspensions. Particle sizing analysis and optical microscopy inspection indicated that the freshly generated micro/nanobubble suspension was polydisperse and the size distribution was bimodal with large amounts of nanobubbles. To develop a nano-sized contrast agent that is small enough to leak through tumor pores, a fractionation to extract smaller bubbles by variation in the time of centrifugation at 20g (relative centrifuge field, RCF) was suggested. The results showed that the population of nanobubbles with a precisely controlled mean diameter could be sorted from the initial polydisperse suspensions to meet the specified requirements. The isolated bubbles were stable over two weeks under the protection of perfluoropropane gas. The acoustic behavior of the nano-sized contrast agent was evaluated using power Doppler imaging in a normal rabbit model. An excellent power Doppler enhancement was found in vivo renal imaging after intravenous injection of the obtained nanobubbles. Given the broad spectrum of potential clinical applications, the nano-sized contrast agent may provide a versatile adjunct for ultrasonic imaging enhancement and/or treatment of tumors.

The fabrication of novel nanobubble ultrasound contrast agent for potential tumor imaging

International Nuclear Information System (INIS)

Xing Zhanwen; Ke Hengte; Yue Xiuli; Dai Zhifei; Wang Jinrui; Zhao Bo; Liu Jibin

2010-01-01

Novel biocompatible nanobubbles were fabricated by ultrasonication of a mixture of Span 60 and polyoxyethylene 40 stearate (PEG40S) followed by differential centrifugation to isolate the relevant subpopulation from the parent suspensions. Particle sizing analysis and optical microscopy inspection indicated that the freshly generated micro/nanobubble suspension was polydisperse and the size distribution was bimodal with large amounts of nanobubbles. To develop a nano-sized contrast agent that is small enough to leak through tumor pores, a fractionation to extract smaller bubbles by variation in the time of centrifugation at 20g (relative centrifuge field, RCF) was suggested. The results showed that the population of nanobubbles with a precisely controlled mean diameter could be sorted from the initial polydisperse suspensions to meet the specified requirements. The isolated bubbles were stable over two weeks under the protection of perfluoropropane gas. The acoustic behavior of the nano-sized contrast agent was evaluated using power Doppler imaging in a normal rabbit model. An excellent power Doppler enhancement was found in vivo renal imaging after intravenous injection of the obtained nanobubbles. Given the broad spectrum of potential clinical applications, the nano-sized contrast agent may provide a versatile adjunct for ultrasonic imaging enhancement and/or treatment of tumors.

The fabrication of novel nanobubble ultrasound contrast agent for potential tumor imaging

Science.gov (United States)

Xing, Zhanwen; Wang, Jinrui; Ke, Hengte; Zhao, Bo; Yue, Xiuli; Dai, Zhifei; Liu, Jibin

2010-04-01

Novel biocompatible nanobubbles were fabricated by ultrasonication of a mixture of Span 60 and polyoxyethylene 40 stearate (PEG40S) followed by differential centrifugation to isolate the relevant subpopulation from the parent suspensions. Particle sizing analysis and optical microscopy inspection indicated that the freshly generated micro/nanobubble suspension was polydisperse and the size distribution was bimodal with large amounts of nanobubbles. To develop a nano-sized contrast agent that is small enough to leak through tumor pores, a fractionation to extract smaller bubbles by variation in the time of centrifugation at 20g (relative centrifuge field, RCF) was suggested. The results showed that the population of nanobubbles with a precisely controlled mean diameter could be sorted from the initial polydisperse suspensions to meet the specified requirements. The isolated bubbles were stable over two weeks under the protection of perfluoropropane gas. The acoustic behavior of the nano-sized contrast agent was evaluated using power Doppler imaging in a normal rabbit model. An excellent power Doppler enhancement was found in vivo renal imaging after intravenous injection of the obtained nanobubbles. Given the broad spectrum of potential clinical applications, the nano-sized contrast agent may provide a versatile adjunct for ultrasonic imaging enhancement and/or treatment of tumors.

Anti-tumor necrosis factor-alpha therapies attenuate adaptive arteriogenesis in the rabbit

NARCIS (Netherlands)

Grundmann, Sebastian; Hoefer, Imo; Ulusans, Susann; van Royen, Niels; Schirmer, Stephan H.; Ozaki, C. Keith; Bode, Christoph; Piek, Jan J.; Buschmann, Ivo

2005-01-01

The specific antagonists of tumor necrosis factor-alpha (TNF-alpha), infliximab and etanercept, are established therapeutic agents for inflammatory diseases such as rheumatoid arthritis and Crohn's disease. Although the importance of TNF-alpha in chronic inflammatory diseases is well established,

Molecular Characterization of Gastric Carcinoma: Therapeutic Implications for Biomarkers and Targets

Directory of Open Access Journals (Sweden)

Lionel Kankeu Fonkoua

2018-03-01

Full Text Available Palliative chemotherapy is the mainstay of treatment of advanced gastric carcinoma (GC. Monoclonal antibodies including trastuzumab, ramucirumab, and pembrolizumab have been shown to provide additional benefits. However, the clinical outcomes are often unpredictable and they can vary widely among patients. Currently, no biomarker is available for predicting treatment response in the individual patient except human epidermal growth factor receptor 2 (HER2 amplification and programmed death-ligand 1 (PD-L1 expression for effectiveness of trastuzumab and pembrolizumab, respectively. Multi-platform molecular analysis of cancer, including GC, may help identify predictive biomarkers to guide selection of therapeutic agents. Molecular classification of GC by The Cancer Genome Atlas Research Network and the Asian Cancer Research Group is expected to identify therapeutic targets and predictive biomarkers. Complementary to molecular characterization of GC is molecular profiling by expression analysis and genomic sequencing of tumor DNA. Initial analysis of patients with gastroesophageal carcinoma demonstrates that the ratio of progression-free survival (PFS on molecular profile (MP-based treatment to PFS on treatment prior to molecular profiling exceeds 1.3, suggesting the potential value of MP in guiding selection of individualized therapy. Future strategies aiming to integrate molecular classification and profiling of tumors with therapeutic agents for achieving the goal of personalized treatment of GC are indicated.

Molecular Characterization of Gastric Carcinoma: Therapeutic Implications for Biomarkers and Targets.

Science.gov (United States)

Kankeu Fonkoua, Lionel; Yee, Nelson S

2018-03-09

Palliative chemotherapy is the mainstay of treatment of advanced gastric carcinoma (GC). Monoclonal antibodies including trastuzumab, ramucirumab, and pembrolizumab have been shown to provide additional benefits. However, the clinical outcomes are often unpredictable and they can vary widely among patients. Currently, no biomarker is available for predicting treatment response in the individual patient except human epidermal growth factor receptor 2 (HER2) amplification and programmed death-ligand 1 (PD-L1) expression for effectiveness of trastuzumab and pembrolizumab, respectively. Multi-platform molecular analysis of cancer, including GC, may help identify predictive biomarkers to guide selection of therapeutic agents. Molecular classification of GC by The Cancer Genome Atlas Research Network and the Asian Cancer Research Group is expected to identify therapeutic targets and predictive biomarkers. Complementary to molecular characterization of GC is molecular profiling by expression analysis and genomic sequencing of tumor DNA. Initial analysis of patients with gastroesophageal carcinoma demonstrates that the ratio of progression-free survival (PFS) on molecular profile (MP)-based treatment to PFS on treatment prior to molecular profiling exceeds 1.3, suggesting the potential value of MP in guiding selection of individualized therapy. Future strategies aiming to integrate molecular classification and profiling of tumors with therapeutic agents for achieving the goal of personalized treatment of GC are indicated.

Radiotherapy in conjunction with 7-hydroxystaurosporine: a multimodal approach with tumor pO2 as a potential marker of therapeutic response.

Science.gov (United States)

Khan, Nadeem; Mupparaju, Sriram P; Hou, Huagang; Lariviere, Jean P; Demidenko, Eugene; Swartz, Harold M; Eastman, Alan

2009-11-01

Checkpoint inhibitors potentially could be used to enhance cell killing by DNA-targeted therapeutic modalities such as radiotherapy. UCN-01 (7-hydroxystaurosporine) inhibits S and G2 checkpoint arrest in the cells of various malignant cell lines and has been investigated in combination with chemotherapy. However, little is known about its potential use in combination with radiotherapy. We report the effect of 20 Gy radiation given in conjunction with UCN-01 on the pO2 and growth of subcutaneous RIF-1 tumors. Multisite EPR oximetry was used for repeated, non-invasive tumor pO2 measurements. The effect of UCN-01 and/or 20 Gy on tumor pO2 and tumor volume was investigated to determine therapeutic outcomes. Untreated RIF-1 tumors were hypoxic with a tissue pO2 of 5-7 mmHg. Treatment with 20 Gy or UCN-01 significantly reduced tumor growth, and a modest increase in tumor pO2 was observed in tumors treated with 20 Gy. However, irradiation with 20 Gy 12 h after UCN-01 treatment resulted in a significant inhibition of tumor growth and a significant increase in tumor pO2 to 16-28 mmHg from day 1 onward compared to the control, UCN-01 or 20-Gy groups. Treatment with UCN-01 12 h after 20 Gy also led to a similar growth inhibition of the tumors and a similar increase in tumor pO2. The changes in tumor pO2 observed after the treatment correlated inversely with the tumor volume in the groups receiving UCN-01 with 20 Gy. This multimodal approach could be used to enhance the outcome of radiotherapy. Furthermore, tumor pO2 could be a potential marker of therapeutic response.

Therapeutic Potential of Curcumin for the Treatment of Brain Tumors

Directory of Open Access Journals (Sweden)

Neil V. Klinger

2016-01-01

Full Text Available Brain malignancies currently carry a poor prognosis despite the current multimodal standard of care that includes surgical resection and adjuvant chemotherapy and radiation. As new therapies are desperately needed, naturally occurring chemical compounds have been studied for their potential chemotherapeutic benefits and low toxicity profile. Curcumin, found in the rhizome of turmeric, has extensive therapeutic promise via its antioxidant, anti-inflammatory, and antiproliferative properties. Preclinical in vitro and in vivo data have shown it to be an effective treatment for brain tumors including glioblastoma multiforme. These effects are potentiated by curcumin’s ability to induce G2/M cell cycle arrest, activation of apoptotic pathways, induction of autophagy, disruption of molecular signaling, inhibition of invasion, and metastasis and by increasing the efficacy of existing chemotherapeutics. Further, clinical data suggest that it has low toxicity in humans even at large doses. Curcumin is a promising nutraceutical compound that should be evaluated in clinical trials for the treatment of human brain tumors.

Nano-Engineered Mesenchymal Stem Cells Increase Therapeutic Efficacy of Anticancer Drug Through True Active Tumor Targeting.

Science.gov (United States)

Layek, Buddhadev; Sadhukha, Tanmoy; Panyam, Jayanth; Prabha, Swayam

2018-06-01

Tumor-targeted drug delivery has the potential to improve therapeutic efficacy and mitigate non-specific toxicity of anticancer drugs. However, current drug delivery approaches rely on inefficient passive accumulation of the drug carrier in the tumor. We have developed a unique, truly active tumor-targeting strategy that relies on engineering mesenchymal stem cells (MSC) with drug-loaded nanoparticles. Our studies using the A549 orthotopic lung tumor model show that nano-engineered MSCs carrying the anticancer drug paclitaxel (PTX) home to tumors and create cellular drug depots that release the drug payload over several days. Despite significantly lower doses of PTX, nano-engineered MSCs resulted in significant inhibition of tumor growth and superior survival. Anticancer efficacy of nano-engineered MSCs was confirmed in immunocompetent C57BL/6 albino female mice bearing orthotopic Lewis Lung Carcinoma (LL/2-luc) tumors. Furthermore, at doses that resulted in equivalent therapeutic efficacy, nano-engineered MSCs had no effect on white blood cell count, whereas PTX solution and PTX nanoparticle treatments caused leukopenia. Biodistribution studies showed that nano-engineered MSCs resulted in greater than 9-fold higher AUC lung of PTX (1.5 μg.day/g) than PTX solution and nanoparticles (0.2 and 0.1 μg.day/g tissue, respectively) in the target lung tumors. Furthermore, the lung-to-liver and the lung-to-spleen ratios of PTX were several folds higher for nano-engineered MSCs relative to those for PTX solution and nanoparticle groups, suggesting that nano-engineered MSCs demonstrate significantly less off-target deposition. In summary, our results demonstrate that nano-engineered MSCs can serve as an efficient carrier for tumor-specific drug delivery and significantly improved anti-cancer efficacy of conventional chemotherapeutic drugs. Mol Cancer Ther; 17(6); 1196-206. ©2018 AACR . ©2018 American Association for Cancer Research.

Improved tumor-targeting MRI contrast agents: Gd(DOTA) conjugates of a cycloalkane-based RGD peptide

International Nuclear Information System (INIS)

Park, Ji-Ae; Lee, Yong Jin; Ko, In Ok; Kim, Tae-Jeong; Chang, Yongmin; Lim, Sang Moo; Kim, Kyeong Min; Kim, Jung Young

2014-01-01

Highlights: • Development of improved tumor-targeting MRI contrast agents. • To increase the targeting ability of RGD, we developed cycloalkane-based RGD peptides. • Gd(DOTA) conjugates of cycloalkane-based RGD peptide show improved tumor signal enhancement in vivo MR images. - Abstract: Two new MRI contrast agents, Gd-DOTA-c(RGD-ACP-K) (1) and Gd-DOTA-c(RGD-ACH-K) (2), which were designed by incorporating aminocyclopentane (ACP)- or aminocyclohexane (ACH)-carboxylic acid into Gd-DOTA (gadolinium-tetraazacyclo dodecanetetraacetic acid) and cyclic RGDK peptides, were synthesized and evaluated for tumor-targeting ability in vitro and in vivo. Binding affinity studies showed that both 1 and 2 exhibited higher affinity for integrin receptors than cyclic RGDyK peptides, which were used as a reference. These complexes showed high relaxivity and good stability in human serum and have the potential to improve target-specific signal enhancement in vivo MR images

Improved tumor-targeting MRI contrast agents: Gd(DOTA) conjugates of a cycloalkane-based RGD peptide

Energy Technology Data Exchange (ETDEWEB)

Park, Ji-Ae, E-mail: jpark@kirams.re.kr [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yong Jin; Ko, In Ok [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Tae-Jeong; Chang, Yongmin [Institute of Biomedical Engineering, Kyungpook National University, Daegu (Korea, Republic of); Lim, Sang Moo [Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Kyeong Min [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Jung Young, E-mail: jykim@kirams.re.kr [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

2014-12-12

Highlights: • Development of improved tumor-targeting MRI contrast agents. • To increase the targeting ability of RGD, we developed cycloalkane-based RGD peptides. • Gd(DOTA) conjugates of cycloalkane-based RGD peptide show improved tumor signal enhancement in vivo MR images. - Abstract: Two new MRI contrast agents, Gd-DOTA-c(RGD-ACP-K) (1) and Gd-DOTA-c(RGD-ACH-K) (2), which were designed by incorporating aminocyclopentane (ACP)- or aminocyclohexane (ACH)-carboxylic acid into Gd-DOTA (gadolinium-tetraazacyclo dodecanetetraacetic acid) and cyclic RGDK peptides, were synthesized and evaluated for tumor-targeting ability in vitro and in vivo. Binding affinity studies showed that both 1 and 2 exhibited higher affinity for integrin receptors than cyclic RGDyK peptides, which were used as a reference. These complexes showed high relaxivity and good stability in human serum and have the potential to improve target-specific signal enhancement in vivo MR images.

Risk of Lymphoma in Patients With Inflammatory Bowel Disease Treated With Anti-Tumor Necrosis Factor Alpha Agents: A Systematic Review and Meta-analysis.

Science.gov (United States)

Yang, Chen; Huang, Junlin; Huang, Xiaowen; Huang, Shaozhuo; Cheng, Jiaxin; Liao, Weixin; Chen, Xuewen; Wang, Xueyi; Dai, Shixue

2018-05-12

The association between anti-tumor necrosis factor alpha agents and the risk of lymphoma in patients with inflammatory bowel disease has already been sufficiently reported. However, the results of these studies are inconsistent. Hence, this analysis was conducted to investigate whether anti-tumor necrosis factor alpha agents can increase the risk of lymphoma in inflammatory bowel disease patients. MEDLINE, EMBASE and the Cochrane Library were searched to identify relevant studies which evaluated the risk of lymphoma in inflammatory bowel disease patients treated with anti-tumor necrosis factor alpha agents. A random-effects meta-analysis was performed to calculate the pooled incidence rate ratios as well as risk ratios. Twelve studies comprising 285811 participants were included. The result showed that there was no significantly increased risk of lymphoma between anti-tumor necrosis factor alpha agents exposed and anti-tumor necrosis factor alpha agents unexposed groups (random effects: incidence rate ratio [IRR], 1.43 95%CI, 0.91-2.25, p= 0.116; random effects: risk ratio [RR], 0.83 95%CI, 0.47-1.48, p=0.534). However, monotherapy of anti-tumor necrosis factor alpha agents (random effects: IRR=1.65, 95%CI, 1.16-2.35; p=0.006; random effects: RR=1.00, 95%CI, 0.39-2.59; p=0.996) or combination therapy (random effects: IRR=3.36, 95%CI, 2.23-5.05; ptumor necrosis factor alpha agents in patients with inflammatory bowel disease is not associated with a higher risk of lymphoma. Combination therapy and anti-tumor necrosis factor alpha agents monotherapy can significantly increase the risk of lymphoma in patients with inflammatory bowel disease.

Combination therapy of potential gene to enhance oral cancer therapeutic effect

Science.gov (United States)

Yeh, Chia-Hsien; Hsu, Yih-Chih

2015-03-01

The epidermal growth factor receptor (EGFR) over-regulation related to uncontrolled cell division and promotes progression in tumor. Over-expression of human epidermal growth factor receptor (EGFR) has been detected in oral cancer cells. EGFR-targeting agents are potential therapeutic modalities for treating oral cancer based on our in vitro study. Liposome nanotechnology is used to encapsulate siRNA and were modified with target ligand to receptors on the surface of tumor cells. We used EGFR siRNA to treat oral cancer in vitro.

Tumor Radiation Therapy Creates Therapeutic Vaccine Responses to the Colorectal Cancer Antigen GUCY2C

Energy Technology Data Exchange (ETDEWEB)

Witek, Matthew [Department of Radiation Oncology, Kimmel Cancer Center, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Blomain, Erik S.; Magee, Michael S.; Xiang, Bo; Waldman, Scott A. [Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Snook, Adam E., E-mail: adam.snook@jefferson.edu [Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania (United States)

2014-04-01

Purpose: Radiation therapy (RT) is thought to produce clinical responses in cancer patients, not only through direct toxicity to cancer cells and supporting tumor stroma cells, but also through activation of immunologic effectors. More recently, RT has potentiated the local and systemic effects of cancer immunotherapy (IT). However, combination regimens that maximize immunologic and clinical efficacy remain undefined. Methods and Materials: We evaluated the impact of local RT on adenoviral-mediated vaccination against the colorectal cancer antigen GUCY2C (Ad5-GUCY2C) in a murine subcutaneous tumor model using mouse CT26 colon cancer cells (CT26-GUCY2C). Immune responses were assessed by ELISpot, and clinical responses were assessed by tumor size and incidence. Results: The specific sequence of tumor-directed RT preceding Ad5-GUCY2C IT transformed inactive therapeutic Ad5-GUCY2C vaccination into a curative vaccine. GUCY2C-specific T cell responses were amplified (P<.05), tumor eradication was maximized (P<.01), and tumor volumes were minimized (P<.001) in mice whose tumors were irradiated before, compared with after, Ad5-GUCY2C vaccination. The immunologic and antitumor efficacy of Ad5-GUCY2C was amplified comparably by unfractionated (8 Gy × 1), or biologically equivalent doses of fractionated (3.5 Gy × 3), RT. The antitumor effects of sequential RT and IT (RT-IT) depended on expression of GUCY2C by tumor cells and the adenoviral vaccine vector, and tumor volumes were inversely related to the magnitude of GUCY2C-specific T cell responses. Moreover, mice cured of CT26-GUCY2C tumors by RT-IT showed long-lasting antigen-dependent protection, resisting tumors formed by GUCY2C-expressing 4T1 breast cancer cells inoculated 50 days after CT26 cells. Conclusions: Optimal sequencing of RT and IT amplifies antigen-specific local and systemic immune responses, revealing novel acute and long-term therapeutic antitumor protection. These observations underscore the importance

Copper-64 Dichloride as Theranostic Agent for Glioblastoma Multiforme: A Preclinical Study

Directory of Open Access Journals (Sweden)

Cristina Ferrari

2015-01-01

Full Text Available Glioblastoma multiforme (GBM is the most common primary malignant brain tumor in adults with a median survival time less than one year. To date, there are only a limited number of effective agents available for GBM therapy and this does not seem to add much survival advantage over the conventional approach based on surgery and radiotherapy. Therefore, the development of novel therapeutic approaches to GBM is essential and those based on radionuclide therapy could be of significant clinical impact. Experimental evidence has clearly demonstrated that cancer cells have a particularly high fractional content of copper inside the nucleus compared to normal cells. This behavior can be conveniently exploited both for diagnosis and for delivering therapeutic payloads (theranostic of the radionuclide copper-64 into the nucleus of cancerous cells by intravenous administration of its simplest chemical form as dichloride salt [64Cu]CuCl2. To evaluate the potential theranostic role of [64Cu]CuCl2 in GBM, the present work reports results from a preclinical study carried out in a xenografted GBM tumor mouse model. Biodistribution data of this new agent were collected using a small-animal PET tomograph. Subsequently, groups of tumor implanted nude mice were treated with [64Cu]CuCl2 to simulate single- and multiple-dose therapy protocols, and results were analyzed to estimate therapeutic efficacy.

Nonviral gene therapy in vivo with PAM-RG4/apoptin as a potential brain tumor therapeutic

Directory of Open Access Journals (Sweden)

An S

2013-02-01

Full Text Available Songhie An,* Kihoon Nam,* Sunghyun Choi, Cheng Z Bai, Yan Lee, Jong-Sang ParkDepartment of Chemistry, Seoul National University, Seoul, Republic of Korea*These authors contributed equally to this workBackground: Glioma is still one of the most complicated forms of brain tumor to remove completely due to its location and the lack of an efficient means to specifically eliminate tumor cells. For these reasons, this study has examined the effectiveness of a nonviral gene therapy approach utilizing a tumor-selective killer gene on a brain tumor xenograft model.Methods and results: The therapeutic apoptin gene was recombined into the JDK plasmid and delivered into human brain tumor cells (U87MG by using a polyamidoamine dendrimer with an arginine surface (PAM-RG4. Studies in vitro showed that the PAM-RG4/apoptin plasmid polyplex exhibited a particularly high transfection activity of >40%. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL assay, 4´,6-Diamidino-2-phenylindole (DAPI TUNEL assay, DAPI staining, and caspase-3 activity assay verified that the tumor cells had undergone apoptosis induced by apoptin. For in vivo studies, the polyplex was injected into tumors, which were induced by injecting U87MG cells intradermally into nude mice. Based on hematoxylin and eosin staining, epidermal growth factor receptor immunohistochemistry results and tumor volume measurement results, tumor growth was effectively inhibited and no specific edema, irritation, or other harm to the skin was observed after polyplex injection. The in vivo expression of apoptin and the induction of apoptosis were verified by reverse-transcription polymerase chain reaction analysis, TUNEL assay, and DAPI staining.Conclusion: The PAM-RG4/apoptin gene polyplex is a strong candidate for brain tumor therapeutics because of the synergistic effect of the carrier's high transfection efficiency (35%–40% in glioma cells and the selective apoptosis-inducing activity of

Production and evaluation of Lutetium-177 maltolate as a possible therapeutic agent

International Nuclear Information System (INIS)

Hakimi, A.; Jalilian, A. R.; Bahrami Samani, A.; Ghannadi Maragheh, M.

2012-01-01

Development of oral therapeutic radiopharmaceuticals is a new concept in radiopharmacy. Due to the interesting therapeutic properties of 177 Lu and oral bioavailability of maltolate (MAL) metal complexes, 177 Lu-maltolate ( 177 Lu-MAL) was developed as a possible therapeutic compound for ultimate oral administration. The specific activity of 2.6-3 GBq/mg was obtained by irradiation of natural Lu 2 O 3 sample with thermal neutron flux of 4x10 13 n.cm -2 .s -1 for Lu-177. The product was converted into chloride form which was further used for labeling maltol (MAL). At optimized conditions a radiochemical purity of about >99% was obtained for 177 Lu-MAL shown by ITLC (specific activity, 970-1000 Mbq/mmole). The stability of the labeled compound as well as the partition coefficient was determined in the final solution up to 24h. Biodistribution studies of Lu-177 chloride and 177 Lu-MAL were carried out in wild-type rats for post-oral distribution phase data. Lu-MAL is a possible therapeutic agent in human malignancies for the bone palliation therapy so the efficacy of the compound should be tested in various animal models.

Novel radiosensitizers for locally advanced epithelial tumors: inhibition of the PI3K/Akt survival pathway in tumor cells and in tumor-associated endothelial cells as a novel treatment strategy?

International Nuclear Information System (INIS)

Riesterer, Oliver; Tenzer, Angela; Zingg, Daniel; Hofstetter, Barbara; Vuong, Van; Pruschy, Martin; Bodis, Stephan

2004-01-01

In locally advanced epithelial malignancies, local control can be achieved with high doses of radiotherapy (RT). Concurrent chemoradiotherapy can improve tumor control in selected solid epithelial adult tumors; however, treatment-related toxicity is of major concern and the therapeutic window often small. Therefore, novel pharmacologic radiosensitizers with a tumor-specific molecular target and a broad therapeutic window are attractive. Because of clonal heterogeneity and the high mutation rate of these tumors, combined treatment with single molecular target radiosensitizers and RT are unlikely to improve sustained local tumor control substantially. Therefore, radiosensitizers modulating entire tumor cell survival pathways in epithelial tumors are of potential clinical use. We discuss the preclinical efficacy and the mechanism of three different, potential radiosensitizers targeting the PTEN/PI3K/Akt survival pathway. These compounds were initially thought to act as single-target agents against growth factor receptors (PKI 166 and PTK 787) or protein kinase C isoforms (PKC 412). We describe an additional target for these compounds. PKI 166 (an epidermal growth factor [EGF] receptor inhibitor) and PKC 412, target the PTEN/PI3K/Akt pathway mainly in tumor cells, and PTK 787 (a vascular endothelial growth factor [VEGF] receptor inhibitor) in endothelial cells. Even for these broader range molecular radiosensitizers, the benefit could be restricted to human epithelial tumor cell clones with a distinct molecular profile. Therefore, these potential radiosensitizers have to be carefully tested in specific model systems before introduction in early clinical trials

A Natural CCR2 Antagonist Relieves Tumor-associated Macrophage-mediated Immunosuppression to Produce a Therapeutic Effect for Liver Cancer

Directory of Open Access Journals (Sweden)

Wenbo Yao

2017-08-01

Full Text Available Hepatocellular carcinoma (HCC is a common malignant tumor in the digestive tract with limited therapeutic choices. Although sorafenib, an orally administered multikinase inhibitor, has produced survival benefits for patients with advanced HCC, favorable clinical outcomes are limited due to individual differences and resistance. The application of immunotherapy, a promising approach for HCC is urgently needed. Macrophage infiltration, mediated by the CCL2/CCR2 axis, is a potential immunotherapeutic target. Here, we report that a natural product from Abies georgei, named 747 and related in structure to kaempferol, exhibits sensitivity and selectivity as a CCR2 antagonist. The specificity of 747 on CCR2 was demonstrated via calcium flux, the binding domain of CCR2 was identified in an extracellular loop by chimera binding assay, and in vivo antagonistic activity of 747 was confirmed through a thioglycollate-induced peritonitis model. In animals, 747 elevated the number of CD8+ T cells in tumors via blocking tumor-infiltrating macrophage-mediated immunosuppression and inhibited orthotopic and subcutaneous tumor growth in a CD8+ T cell-dependent manner. Further, 747 enhanced the therapeutic efficacy of low-dose sorafenib without obvious toxicity, through elevating the numbers of intra-tumoral CD8+ T cells and increasing death of tumor cells. Thus, we have discovered a natural CCR2 antagonist and have provided a new perspective on development of this antagonist for treatment of HCC. In mouse models of HCC, 747 enhanced the tumor immunosuppressive microenvironment and potentiated the therapeutic effect of sorafenib, indicating that the combination of an immunomodulator with a chemotherapeutic drug could be a new approach for treating HCC.

MALDI Mass Spectrometry Imaging for Evaluation of Therapeutics in Colorectal Tumor Organoids

Science.gov (United States)

Liu, Xin; Flinders, Colin; Mumenthaler, Shannon M.; Hummon, Amanda B.

2018-03-01

Patient-derived colorectal tumor organoids (CTOs) closely recapitulate the complex morphological, phenotypic, and genetic features observed in in vivo tumors. Therefore, evaluation of drug distribution and metabolism in this model system can provide valuable information to predict the clinical outcome of a therapeutic response in individual patients. In this report, we applied matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to examine the spatial distribution of the drug irinotecan and its metabolites in CTOs from two patients. Irinotecan is a prodrug and is often prescribed as part of therapeutic regimes for patients with advanced colorectal cancer. Irinotecan shows a time-dependent and concentration-dependent permeability and metabolism in the CTOs. More interestingly, the active metabolite SN-38 does not co-localize well with the parent drug irinotecan and the inactive metabolite SN-38G. The phenotypic effect of irinotecan metabolism was also confirmed by a viability study showing significantly reduced proliferation in the drug treated CTOs. MALDI-MSI can be used to investigate various pharmaceutical compounds in CTOs derived from different patients. By analyzing multiple CTOs from a patient, this method could be used to predict patient-specific drug responses and help to improve personalized dosing regimens. [Figure not available: see fulltext.

Radiation and concurrent chemotherapy for the treatment of Lewis lung tumor and B16 melanoma tumor in C57/BL mice

International Nuclear Information System (INIS)

Pedersen, J.E.; Barron, G.

1984-01-01

C57/BL mice bearing either Lewis lung tumor or B16 melanoma tumor were treated with radiation and concurrent chemotherapy. The treatment results were determined in vivo by tumor regrowth delay assay. When continuous infusion of either Cyclophosphamide (CYCLO) or 5-Fluorouracil (5-FU) or Adriamycin (ADRIA) or Mitomycin-C (MITO-C) was used in combination with continuous radiation at 1 cGy/min, no increase in tumor regrowth delay was observed over that of radiation alone. When multiple drug chemotherapy, FAM (5-FU, ADRIA, MITO-C) was administered in combination with radiation at 80 cGy/min, no increase in tumor regrowth delay was observed over that of radiation alone. In these two murine tumor models, when clinically relevant concentrations of commonly used chemotherapy agents were combined with radiation, no therapeutic advantage was observed

Availability of perfluoroctylbromide (PFOB) emulsion used as agent in the liver tumor imaging of computed tomography (CT)

International Nuclear Information System (INIS)

Ozawa, Takachika

1986-01-01

We carried out a fundamental study on the availability of perfluoroctylbromide (PFOB) emulsion used as an agent in the liver tumor imaging of computed tomography (CT). For this study, we used emulsified yolk phospolipid as a surfactant for PFOB emulsion because it is generally considered to have higher safety relative to the administration to the humans. In the rabbits' liver tumor model in which VX 2 tumor cell was implanted into their livers, we observed increases in the CT values of the livers when 5 to 10 ml/kg of PFOB emulsion (20 % w/v) was administered into the vein, and also ringlike enhancement and increases in the CT values on the tumor rim when 20 ml/kg of PFOB emulsion was administered. In addition, in the chemical analysis of a gas chromatography, we also observed significant increases in the PFOB concentration on the tumor rim, compared with those of normal liver parenchyma, when 20 ml/kg of PFOB emulsion was given. In the finding of CT values in the human liver tumor by means of organ perfusion system, we recognized increases in the CT values (induced by the accumulation of PFOB emulsion) on the rim of the metastatic tumor of colon cancer. These results suggest that PFOB emulsion has certain availability as an agent for the liver tumor imaging of computed tomography (CT). (author)

How should immunomodulators be optimized when used as combination therapy with anti-tumor necrosis factor agents in the management of inflammatory bowel disease?

Science.gov (United States)

Ward, Mark G; Irving, Peter M; Sparrow, Miles P

2015-10-28

In the last 15 years the management of inflammatory bowel disease has evolved greatly, largely through the increased use of immunomodulators and, especially, anti-tumor necrosis factor (anti-TNF) biologic agents. Within this time period, confidence in the use of anti-TNFs has increased, whilst, especially in recent years, the efficacy and safety of thiopurines has been questioned. Yet despite recent concerns regarding the risk: benefit profile of thiopurines, combination therapy with an immunomodulator and an anti-TNF has emerged as the recommended treatment strategy for the majority of patients with moderate-severe disease, especially those who are recently diagnosed. Concurrently, therapeutic drug monitoring has emerged as a means of optimizing the dosage of both immunomodulators and anti-TNFs. However the recommended therapeutic target levels for both drug classes were largely derived from studies of monotherapy with either agent, or studies underpowered to analyze outcomes in combination therapy patients. It has been assumed that these target levels are applicable to patients on combination therapy also, however there are few data to support this. Similarly, the timing and duration of treatment with immunomodulators when used in combination therapy remains unknown. Recent attention, including post hoc analyses of the pivotal registration trials, has focused on the optimization of anti-TNF agents, when used as either monotherapy or combination therapy. This review will instead focus on how best to optimize immunomodulators when used in combination therapy, including an evaluation of recent data addressing unanswered questions regarding the optimal timing, dosage and duration of immunomodulator therapy in combination therapy patients.

In vivo therapeutic responses contingent on Fanconi anemia/BRCA2 status of the tumor.

Science.gov (United States)

van der Heijden, Michiel S; Brody, Jonathan R; Dezentje, David A; Gallmeier, Eike; Cunningham, Steven C; Swartz, Michael J; DeMarzo, Angelo M; Offerhaus, G Johan A; Isacoff, William H; Hruban, Ralph H; Kern, Scott E

2005-10-15

BRCA2, FANCC, and FANCG gene mutations are present in a subset of pancreatic cancer. Defects in these genes could lead to hypersensitivity to interstrand cross-linkers in vivo and a more optimal treatment of pancreatic cancer patients based on the genetic profile of the tumor. Two retrovirally complemented pancreatic cancer cell lines having defects in the Fanconi anemia pathway, PL11 (FANCC-mutated) and Hs766T (FANCG-mutated), as well as several parental pancreatic cancer cell lines with or without mutations in the Fanconi anemia/BRCA2 pathway, were assayed for in vitro and in vivo sensitivities to various chemotherapeutic agents. A distinct dichotomy of drug responses was observed. Fanconi anemia-defective cancer cells were hypersensitive to the cross-linking agents mitomycin C (MMC), cisplatin, chlorambucil, and melphalan but not to 5-fluorouracil, gemcitabine, doxorubicin, etoposide, vinblastine, or paclitaxel. Hypersensitivity to cross-linking agents was confirmed in vivo; FANCC-deficient xenografts of PL11 and BRCA2-deficient xenografts of CAPAN1 regressed on treatment with two different regimens of MMC whereas Fanconi anemia-proficient xenografts did not. The MMC response comprised cell cycle arrest, apoptosis, and necrosis. Xenografts of PL11 also regressed after a single dose of cyclophosphamide whereas xenografts of genetically complemented PL11(FANCC) did not. MMC or other cross-linking agents as a clinical therapy for pancreatic cancer patients with tumors harboring defects in the Fanconi anemia/BRCA2 pathway should be specifically investigated.

Hierarchical Targeting Strategy for Enhanced Tumor Tissue Accumulation/Retention and Cellular Internalization.

Science.gov (United States)

Wang, Sheng; Huang, Peng; Chen, Xiaoyuan

2016-09-01

Targeted delivery of therapeutic agents is an important way to improve the therapeutic index and reduce side effects. To design nanoparticles for targeted delivery, both enhanced tumor tissue accumulation/retention and enhanced cellular internalization should be considered simultaneously. So far, there have been very few nanoparticles with immutable structures that can achieve this goal efficiently. Hierarchical targeting, a novel targeting strategy based on stimuli responsiveness, shows good potential to enhance both tumor tissue accumulation/retention and cellular internalization. Here, the recent design and development of hierarchical targeting nanoplatforms, based on changeable particle sizes, switchable surface charges and activatable surface ligands, will be introduced. In general, the targeting moieties in these nanoplatforms are not activated during blood circulation for efficient tumor tissue accumulation, but re-activated by certain internal or external stimuli in the tumor microenvironment for enhanced cellular internalization. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Deoxypodophyllotoxin: a promising therapeutic agent from herbal medicine.

Science.gov (United States)

Khaled, Meyada; Jiang, Zhen-Zhou; Zhang, Lu-Yong

2013-08-26

Recently, biologically active compounds isolated from plants used in herbal medicine have been the center of interest. Deoxypodophyllotoxin (DPT), structurally closely related to the lignan podophyllotoxin, is a potent antitumor and anti-inflammatory agent. However, DPT has not been used clinically yet. Also, DPT from natural sources seems to be unavailable. Hence, it is important to establish alternative resources for the production of such lignan; especially that it is used as a precursor for the semi-synthesis of the cytostatic drugs etoposide phosphate and teniposide. The update paper provides an overview of DPT as an effective anticancer natural compound and a leader for cytotoxic drugs synthesis and development in order to highlight the gaps in our knowledge and explore future research needs. The present review covers the literature available from 1877 to 2012. The information was collected via electronic search using Chinese papers and the major scientific databases including PubMed, Sciencedirect, Web of Science and Google Scholar using the keywords. All abstracts and full-text articles reporting database on the history and current status of DPT were gathered and analyzed. Plants containing DPT have played an important role in traditional medicine. In light of the in vitro pharmacological investigations, DPT is a high valuable medicinal agent that has anti-tumor, anti-proliferative, anti-inflammatory and anti-allergic properties. Further, DPT is an important precursor for the cytotoxic aryltetralin lignan, podophyllotoxin, which is used to obtain semisynthetic derivatives like etoposide and teniposide used in cancer therapy. However, most studies have focused on the in vitro data. Therefore, DPT has not been used clinically yet. DPT has emerged as a potent chemical agent from herbal medicine. Therefore, in vivo studies are needed to carry out clinical trials in humans and enable the development of new anti-cancer agents. In addition, DPT from commercial

Therapeutic efficacy and mechanism of action of ethamsylate, a long-standing hemostatic agent.

Science.gov (United States)

Garay, Ricardo P; Chiavaroli, Carlo; Hannaert, Patrick

2006-01-01

Ethamsylate (2,5-dihydroxy-benzene-sulfonate diethylammonium salt) is a synthetic hemostatic drug indicated in cases of capillary bleeding. This review covers more than 40 years of intensive clinical and fundamental research with ethamsylate. First, we summarize the large medical literature concerning its clinical efficacy. Of these, well-controlled clinical trials clearly showed the therapeutic efficacy of ethamsylate in dysfunctional uterine bleeding, with the magnitude of blood-loss reduction being directly proportional to the severity of the menorrhagia. Other well-controlled clinical trials showed therapeutic efficacy of ethamsylate in periventricular hemorrhage in very low birth weight babies and surgical or postsurgical capillary bleeding. Second, we review the numerous investigations performed to elucidate the mechanism of action of ethamsylate. Ethamsylate acts on the first step of hemostasis by improving platelet adhesiveness and restoring capillary resistance. Recent studies showed that ethamsylate promotes P-selectin-dependent, platelet adhesive mechanisms. Finally, we compare ethamsylate with other recent hemostatic agents. It is suggested that the place of ethamsylate as a hemostatic agent is that of a mild but well-tolerated drug, particularly useful in dysfunctional uterine bleeding when contraception is not needed.

Integrated nanotechnology platform for tumor-targeted multimodal imaging and therapeutic cargo release.

Science.gov (United States)

Hosoya, Hitomi; Dobroff, Andrey S; Driessen, Wouter H P; Cristini, Vittorio; Brinker, Lina M; Staquicini, Fernanda I; Cardó-Vila, Marina; D'Angelo, Sara; Ferrara, Fortunato; Proneth, Bettina; Lin, Yu-Shen; Dunphy, Darren R; Dogra, Prashant; Melancon, Marites P; Stafford, R Jason; Miyazono, Kohei; Gelovani, Juri G; Kataoka, Kazunori; Brinker, C Jeffrey; Sidman, Richard L; Arap, Wadih; Pasqualini, Renata

2016-02-16

A major challenge of targeted molecular imaging and drug delivery in cancer is establishing a functional combination of ligand-directed cargo with a triggered release system. Here we develop a hydrogel-based nanotechnology platform that integrates tumor targeting, photon-to-heat conversion, and triggered drug delivery within a single nanostructure to enable multimodal imaging and controlled release of therapeutic cargo. In proof-of-concept experiments, we show a broad range of ligand peptide-based applications with phage particles, heat-sensitive liposomes, or mesoporous silica nanoparticles that self-assemble into a hydrogel for tumor-targeted drug delivery. Because nanoparticles pack densely within the nanocarrier, their surface plasmon resonance shifts to near-infrared, thereby enabling a laser-mediated photothermal mechanism of cargo release. We demonstrate both noninvasive imaging and targeted drug delivery in preclinical mouse models of breast and prostate cancer. Finally, we applied mathematical modeling to predict and confirm tumor targeting and drug delivery. These results are meaningful steps toward the design and initial translation of an enabling nanotechnology platform with potential for broad clinical applications.

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.

Tumor blood vessel "normalization" improves the therapeutic efficacy of boron neutron capture therapy (BNCT) in experimental oral cancer

Energy Technology Data Exchange (ETDEWEB)

D. W. Nigg

2012-01-01

We previously demonstrated the efficacy of BNCT mediated by boronophenylalanine (BPA) to treat tumors in a hamster cheek pouch model of oral cancer with no normal tissue radiotoxicity and moderate, albeit reversible, mucositis in precancerous tissue around treated tumors. It is known that boron targeting of the largest possible proportion of tumor cells contributes to the success of BNCT and that tumor blood vessel normalization improves drug delivery to the tumor. Within this context, the aim of the present study was to evaluate the effect of blood vessel normalization on the therapeutic efficacy and potential radiotoxicity of BNCT in the hamster cheek pouch model of oral cancer.

Tumor blood vessel 'normalization' improves the therapeutic efficacy of boron neutron capture therapy (BNCT) in experimental oral cancer

International Nuclear Information System (INIS)

Nigg, D.W.

2012-01-01

We previously demonstrated the efficacy of BNCT mediated by boronophenylalanine (BPA) to treat tumors in a hamster cheek pouch model of oral cancer with no normal tissue radiotoxicity and moderate, albeit reversible, mucositis in precancerous tissue around treated tumors. It is known that boron targeting of the largest possible proportion of tumor cells contributes to the success of BNCT and that tumor blood vessel normalization improves drug delivery to the tumor. Within this context, the aim of the present study was to evaluate the effect of blood vessel normalization on the therapeutic efficacy and potential radiotoxicity of BNCT in the hamster cheek pouch model of oral cancer.

Novel nitric oxide generating compound glycidyl nitrate enhances the therapeutic efficacy of chemotherapy and radiotherapy.

Science.gov (United States)

Ning, Shoucheng; Bednarski, Mark; Oronsky, Bryan; Scicinski, Jan; Knox, Susan J

2014-05-09

Selective release of nitric oxide (NO) in tumors could improve the tumor blood flow and drug delivery for chemotherapeutic agents and radiotherapy, thereby increasing the therapeutic index. Glycidyl nitrate (GLYN) is a NO generating small molecule, and has ability to release NO on bioactivation in SCC VII tumor cells. GLYN-induced intracellular NO generation was significantly attenuated by NO scavenger carboxy-PTIO (cPTIO) and NAC. GLYN significantly increases tumor blood flow, but has no effect on the blood flow of normal tissues in tumor-bearing mice. When used with cisplatin, GLYN significantly increased the tumor growth inhibition effect of cisplatin. GLYN also had a modest radiosensitizing effect in vitro and in vivo. GLYN was well tolerated and there were no acute toxicities found at its effective therapeutic doses in preclinical studies. These results suggest that GLYN is a promising new drug for use with chemotherapy and radiotherapy, and provide a compelling rationale for future studies of GLYN and related compounds. Copyright © 2014 Elsevier Inc. All rights reserved.

A novel Tc-99m and fluorescence-labeled arginine-arginine-leucine-containing peptide as a multimodal tumor imaging agent in a murine tumor model.

Science.gov (United States)

Kim, Myoung Hyoun; Kim, Seul-Gi; Kim, Dae-Weung

2018-06-15

We developed a Tc-99m and TAMRA-labeled peptide, Tc-99m arginine-arginine-leucine (RRL) peptide (TAMRA-GHEG-ECG-RRL), to target tumor cells and evaluated the diagnostic performance of Tc-99m TAMRA-GHEG-ECG-RRL as a dual-modality imaging agent for tumor in a murine model. TAMRA-GHEG-ECG-RRL was synthesized using Fmoc solid-phase peptide synthesis. Binding affinity and in vitro cellular uptake studies were performed. Gamma camera imaging, biodistribution, and ex vivo imaging studies were performed in murine models with PC-3 tumors. Tumor tissue slides were prepared and analyzed with immunohistochemistry using confocal microscopy. After radiolabeling procedures with Tc-99m, Tc-99m TAMRA-GHEG-ECG-RRL complexes were prepared in high yield (>96%). The K d of Tc-99m TAMRA-GHEG-ECG-RRL determined by saturation binding was 41.7 ± 7.8 nM. Confocal microscopy images of PC-3 cells incubated with TAMRA-GHEG-ECG-RRL showed strong fluorescence in the cytoplasm. Gamma camera imaging revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-RRL in tumors. Tumor uptake was effectively blocked by the coinjection of an excess concentration of RRL. Specific uptake of Tc-99m TAMRA-GHEG-ECG-RRL was confirmed by biodistribution, ex vivo imaging, and immunohistochemistry stain studies. In conclusion, in vivo and in vitro studies revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-RRL in tumors. Tc-99m TAMRA-GHEG-ECG-RRL has potential as a dual-modality tumor imaging agent. Copyright © 2018 John Wiley & Sons, Ltd.

A review of 99mTc labeled myocardial imaging agents for tumor-positive imaging

International Nuclear Information System (INIS)

Xing Shian; Zhang Yongxue; An Rui

2002-01-01

The tumor-positive imaging with high sensitivity and specificity was useful in primary tumor and recurrences and metastases. The 99m Tc labeled myocardial imaging agents are easily available and stable and the radiochemical purity is high. 99m Tc is the preferred choice in routine works because its physical properties. The preparation, quality control, mechanism of accumulation and the clinical use of 99m Tc-sestamibi, 99m Tc-tetrofosmin, 99m Tc-furifosmin, and 99m Tc-N-NOET were reviewed

Advances in Molecular Imaging of Locally Delivered Targeted Therapeutics for Central Nervous System Tumors

Directory of Open Access Journals (Sweden)

Umberto Tosi

2017-02-01

Full Text Available Thanks to the recent advances in the development of chemotherapeutics, the morbidity and mortality of many cancers has decreased significantly. However, compared to oncology in general, the field of neuro-oncology has lagged behind. While new molecularly targeted chemotherapeutics have emerged, the impermeability of the blood–brain barrier (BBB renders systemic delivery of these clinical agents suboptimal. To circumvent the BBB, novel routes of administration are being applied in the clinic, ranging from intra-arterial infusion and direct infusion into the target tissue (convection enhanced delivery (CED to the use of focused ultrasound to temporarily disrupt the BBB. However, the current system depends on a “wait-and-see” approach, whereby drug delivery is deemed successful only when a specific clinical outcome is observed. The shortcomings of this approach are evident, as a failed delivery that needs immediate refinement cannot be observed and corrected. In response to this problem, new theranostic agents, compounds with both imaging and therapeutic potential, are being developed, paving the way for improved and monitored delivery to central nervous system (CNS malignancies. In this review, we focus on the advances and the challenges to improve early cancer detection, selection of targeted therapy, and evaluation of therapeutic efficacy, brought forth by the development of these new agents.

Advances in Molecular Imaging of Locally Delivered Targeted Therapeutics for Central Nervous System Tumors

Science.gov (United States)

Tosi, Umberto; Marnell, Christopher S.; Chang, Raymond; Cho, William C.; Ting, Richard; Maachani, Uday B.; Souweidane, Mark M.

2017-01-01

Thanks to the recent advances in the development of chemotherapeutics, the morbidity and mortality of many cancers has decreased significantly. However, compared to oncology in general, the field of neuro-oncology has lagged behind. While new molecularly targeted chemotherapeutics have emerged, the impermeability of the blood–brain barrier (BBB) renders systemic delivery of these clinical agents suboptimal. To circumvent the BBB, novel routes of administration are being applied in the clinic, ranging from intra-arterial infusion and direct infusion into the target tissue (convection enhanced delivery (CED)) to the use of focused ultrasound to temporarily disrupt the BBB. However, the current system depends on a “wait-and-see” approach, whereby drug delivery is deemed successful only when a specific clinical outcome is observed. The shortcomings of this approach are evident, as a failed delivery that needs immediate refinement cannot be observed and corrected. In response to this problem, new theranostic agents, compounds with both imaging and therapeutic potential, are being developed, paving the way for improved and monitored delivery to central nervous system (CNS) malignancies. In this review, we focus on the advances and the challenges to improve early cancer detection, selection of targeted therapy, and evaluation of therapeutic efficacy, brought forth by the development of these new agents. PMID:28208698

Effect of Au-dextran NPs as anti-tumor agent against EAC and solid tumor in mice by biochemical evaluations and histopathological investigations.

Science.gov (United States)

Medhat, Dalia; Hussein, Jihan; El-Naggar, Mehrez E; Attia, Mohamed F; Anwar, Mona; Latif, Yasmine Abdel; Booles, Hoda F; Morsy, Safaa; Farrag, Abdel Razik; Khalil, Wagdy K B; El-Khayat, Zakaria

2017-07-01

Dextran-capped gold nanoparticles (Au-dextran NPs) were prepared exploiting the natural polysaccharide polymer as both reducing and stabilizing agent in the synthesis process, aiming at studying their antitumor effect on solid carcinoma and EAC-bearing mice. To this end, Au-dextran NPs were designed via simple eco-friendly chemical reaction and they were characterized revealing the monodispersed particles with narrow distributed size of around 49nm with high negative charge. In vivo experiments were performed on mice. Biochemical analysis of liver and kidney functions and oxidation stress ratio in addition to histopathological investigations of such tumor tissues were done demonstrating the potentiality of Au-dextran NPs as antitumor agent. The obtained results revealed that EAC and solid tumors caused significant increase in liver and kidney functions, liver oxidant parameters, alpha feto protein levels and diminished liver antioxidant accompanied by positive expression of tumor protein p53 of liver while the treatment with Au-dextran NPs for both types caused improvement in liver and kidney functions, increased liver antioxidant, increased the expression level of B-cell lymphoma 2 gene and subsequently suppressed the apoptotic pathway. As a result, the obtained data provides significant antitumor effects of the Au-dextran NPs in both Ehrlich ascites and solid tumor in mice models. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Insights into the Antimicrobial Properties of Hepcidins: Advantages and Drawbacks as Potential Therapeutic Agents

Directory of Open Access Journals (Sweden)

Lisa Lombardi

2015-04-01

Full Text Available The increasing frequency of multi-drug resistant microorganisms has driven research into alternative therapeutic strategies. In this respect, natural antimicrobial peptides (AMPs hold much promise as candidates for the development of novel antibiotics. However, AMPs have some intrinsic drawbacks, such as partial degradation by host proteases or inhibition by host body fluid composition, potential toxicity, and high production costs. This review focuses on the hepcidins, which are peptides produced by the human liver with a known role in iron homeostasis, as well by numerous other organisms (including fish, reptiles, other mammals, and their potential as antibacterial and antifungal agents. Interestingly, the antimicrobial properties of human hepcidins are enhanced at acidic pH, rendering these peptides appealing for the design of new drugs targeting infections that occur in body areas with acidic physiological pH. This review not only considers current research on the direct killing activity of these peptides, but evaluates the potential application of these molecules as coating agents preventing biofilm formation and critically assesses technical obstacles preventing their therapeutic application.

Polymer Therapeutics: Biomarkers and New Approaches for Personalized Cancer Treatment.

Science.gov (United States)

Atkinson, Stuart P; Andreu, Zoraida; Vicent, María J

2018-01-23

Polymer therapeutics (PTs) provides a potentially exciting approach for the treatment of many diseases by enhancing aqueous solubility and altering drug pharmacokinetics at both the whole organism and subcellular level leading to improved therapeutic outcomes. However, the failure of many polymer-drug conjugates in clinical trials suggests that we may need to stratify patients in order to match each patient to the right PT. In this concise review, we hope to assess potential PT-specific biomarkers for cancer treatment, with a focus on new studies, detection methods, new models and the opportunities this knowledge will bring for the development of novel PT-based anti-cancer strategies. We discuss the various "hurdles" that a given PT faces on its passage from the syringe to the tumor (and beyond), including the passage through the bloodstream, tumor targeting, tumor uptake and the intracellular release of the active agent. However, we also discuss other relevant concepts and new considerations in the field, which we hope will provide new insight into the possible applications of PT-related biomarkers.

TRAIL death receptors and cancer therapeutics

International Nuclear Information System (INIS)

Huang Ying; Sheikh, M. Saeed

2007-01-01

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) also known as Apo2L is an apoptotic molecule that belongs to the tumor necrosis factor superfamily of cytokines. It mediates its apoptotic effects via its cognate death receptors including DR4 and DR5. Agonistic monoclonal antibodies have also been developed that selectively activate TRAIL death receptors to mediate apoptosis. Multiple clinically relevant agents also upregulate the expression of TRAIL death receptors, and cooperate with TRAIL as well as DR4 and DR5-specific agonistic antibodies to exhibit tumor cell killing. TRAIL is currently in phase I clinical trials, whereas DR4 and DR5-specific agonistic antibodies have been tested in phase I and II studies. Thus, TRAIL has clearly distinguished itself from the other family members including TNF-alpha and FasL both of which could not make it to the clinic due to their toxic nature. It is therefore, evident that the future of TRAIL-based therapeutic approaches looks brighter

RGD-based strategies for selective delivery of therapeutics and imaging agents to the tumour vasculature

NARCIS (Netherlands)

Temming, K; Molema, G; Kok, RJ

2005-01-01

During the past decade, RGD-peptides have become a popular tool for the targeting of drugs and imaging agents to a(v)beta(3)-integrin expressing tumour vasculature. RGD-peptides have been introduced by recombinant means into therapeutic proteins and viruses. Chemical means have been applied to

Combination of aspartic acid and glutamic acid inhibits tumor cell proliferation.

Science.gov (United States)

Yamaguchi, Yoshie; Yamamoto, Katsunori; Sato, Yoshinori; Inoue, Shinjiro; Morinaga, Tetsuo; Hirano, Eiichi

2016-01-01

Placental extract contains several biologically active compounds, and pharmacological induction of placental extract has therapeutic effects, such as improving liver function in patients with hepatitis or cirrhosis. Here, we searched for novel molecules with an anti-tumor activity in placental extracts. Active molecules were separated by chromatographic analysis, and their antiproliferative activities were determined by a colorimetric assay. We identified aspartic acid and glutamic acid to possess the antiproliferative activity against human hepatoma cells. Furthermore, we showed that the combination of aspartic acid and glutamic acid exhibited enhanced antiproliferative activity, and inhibited Akt phosphorylation. We also examined in vivo tumor inhibition activity using the rabbit VX2 liver tumor model. The treatment mixture (emulsion of the amino acids with Lipiodol) administered by hepatic artery injection inhibited tumor cell growth of the rabbit VX2 liver. These results suggest that the combination of aspartic acid and glutamic acid may be useful for induction of tumor cell death, and has the potential for clinical use as a cancer therapeutic agent.

Induced-Decay of Glycine Decarboxylase Transcripts as an Anticancer Therapeutic Strategy for Non-Small-Cell Lung Carcinoma

Directory of Open Access Journals (Sweden)

Jing Lin

2017-12-01

Full Text Available Self-renewing tumor-initiating cells (TICs are thought to be responsible for tumor recurrence and chemo-resistance. Glycine decarboxylase, encoded by the GLDC gene, is reported to be overexpressed in TIC-enriched primary non-small-cell lung carcinoma (NSCLC. GLDC is a component of the mitochondrial glycine cleavage system, and its high expression is required for growth and tumorigenic capacity. Currently, there are no therapeutic agents against GLDC. As a therapeutic strategy, we have designed and tested splicing-modulating steric hindrance antisense oligonucleotides (shAONs that efficiently induce exon skipping (half maximal inhibitory concentration [IC50] at 3.5–7 nM, disrupt the open reading frame (ORF of GLDC transcript (predisposing it for nonsense-mediated decay, halt cell proliferation, and prevent colony formation in both A549 cells and TIC-enriched NSCLC tumor sphere cells (TS32. One candidate shAON causes 60% inhibition of tumor growth in mice transplanted with TS32. Thus, our shAONs candidates can effectively inhibit the expression of NSCLC-associated metabolic enzyme GLDC and may have promising therapeutic implications.

Iron addiction: a novel therapeutic target in ovarian cancer

International Nuclear Information System (INIS)

Basuli, D.

2017-01-01

Ovarian cancer is a lethal malignancy that has not seen a major therapeutic advance in over 30 years. We demonstrate that ovarian cancer exhibits a targetable alteration in iron metabolism. Ferroportin (FPN), the iron efflux pump, is decreased, and transferrin receptor (TFR1), the iron importer, is increased in tumor tissue from patients with high grade but not low grade serous ovarian cancer. A similar profile of decreased FPN and increased TFR1 is observed in a genetic model of ovarian cancer tumor-initiating cells (TICs). The net result of these changes is an accumulation of excess intracellular iron and an augmented dependence on iron for proliferation. A forced reduction in intracellular iron reduces the proliferation of ovarian cancer TICs in vitro, and inhibits both tumor growth and intraperitoneal dissemination of tumor cells in vivo. Some mechanistic studies demonstrate that iron increases metastatic spread by facilitating invasion through expression of matrix metalloproteases and synthesis of interleukin 6 (IL-6). Here, we show that the iron dependence of ovarian cancer TICs renders them exquisitely sensitive in vivo to agents that induce iron-dependent cell death (ferroptosis) as well as iron chelators, and thus creates a metabolic vulnerability that can be exploited therapeutically.

Cytotoxic T lymphocyte-dependent tumor growth inhibition by a vascular endothelial growth factor-superantigen conjugate

Energy Technology Data Exchange (ETDEWEB)

Sun, Qingwen [Shanghai Chest Hospital, Shanghai 200433 (China); State Key Laboratory of Genetic Engineering, Fudan University, Shanghai 200433 (China); Jiang, Songmin [State Key Laboratory of Genetic Engineering, Fudan University, Shanghai 200433 (China); Han, Baohui [Shanghai Chest Hospital, Shanghai 200433 (China); Sun, Tongwen [Wuhan Junyu Innovation Pharmaceuticals, Inc., Wuhan 430079 (China); Li, Zhengnan; Zhao, Lina; Gao, Qiang [College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China); Sun, Jialin, E-mail: jialin_sun@126.com [Wuhan Junyu Innovation Pharmaceuticals, Inc., Wuhan 430079 (China)

2012-11-02

Highlights: Black-Right-Pointing-Pointer We construct and purify a fusion protein VEGF-SEA. Black-Right-Pointing-Pointer VEGF-SEA strongly repressed the growth of murine solid sarcoma 180 (S180) tumors. Black-Right-Pointing-Pointer T cells driven by VEGF-SEA were accumulated around tumor cells bearing VEGFR by mice image model. Black-Right-Pointing-Pointer VEGF-SEA can serve as a tumor targeting agent and sequester CTLs into the tumor site. Black-Right-Pointing-Pointer The induced CTLs could release the cytokines, perforins and granzyme B to kill the tumor cells. -- Abstract: T cells are major lymphocytes in the blood and passengers across the tumor vasculature. If these T cells are retained in the tumor site, a therapeutic potential will be gained by turning them into tumor-reactive cytotoxic T lymphocytes (CTLs). A fusion protein composed of human vascular endothelial growth factor (VEGF) and staphylococcal enterotoxin A (SEA) with a D227A mutation strongly repressed the growth of murine solid sarcoma 180 (S180) tumors (control versus VEGF-SEA treated with 15 {mu}g, mean tumor weight: 1.128 g versus 0.252 g, difference = 0.876 g). CD4{sup +} and CD8{sup +} T cells driven by VEGF-SEA were accumulated around VEGFR expressing tumor cells and the induced CTLs could release the tumoricidal cytokines, such as interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha). Meanwhile, intratumoral CTLs secreted cytolytic pore-forming perforin and granzyme B proteins around tumor cells, leading to the death of tumor cells. The labeled fusion proteins were gradually targeted to the tumor site in an imaging mice model. These results show that VEGF-SEA can serve as a tumor targeting agent and sequester active infiltrating CTLs into the tumor site to kill tumor cells, and could therefore be a potential therapeutical drug for a variety of cancers.

Cytotoxic T lymphocyte-dependent tumor growth inhibition by a vascular endothelial growth factor–superantigen conjugate

International Nuclear Information System (INIS)

Sun, Qingwen; Jiang, Songmin; Han, Baohui; Sun, Tongwen; Li, Zhengnan; Zhao, Lina; Gao, Qiang; Sun, Jialin

2012-01-01

Highlights: ► We construct and purify a fusion protein VEGF–SEA. ► VEGF–SEA strongly repressed the growth of murine solid sarcoma 180 (S180) tumors. ► T cells driven by VEGF–SEA were accumulated around tumor cells bearing VEGFR by mice image model. ► VEGF–SEA can serve as a tumor targeting agent and sequester CTLs into the tumor site. ► The induced CTLs could release the cytokines, perforins and granzyme B to kill the tumor cells. -- Abstract: T cells are major lymphocytes in the blood and passengers across the tumor vasculature. If these T cells are retained in the tumor site, a therapeutic potential will be gained by turning them into tumor-reactive cytotoxic T lymphocytes (CTLs). A fusion protein composed of human vascular endothelial growth factor (VEGF) and staphylococcal enterotoxin A (SEA) with a D227A mutation strongly repressed the growth of murine solid sarcoma 180 (S180) tumors (control versus VEGF–SEA treated with 15 μg, mean tumor weight: 1.128 g versus 0.252 g, difference = 0.876 g). CD4 + and CD8 + T cells driven by VEGF–SEA were accumulated around VEGFR expressing tumor cells and the induced CTLs could release the tumoricidal cytokines, such as interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha). Meanwhile, intratumoral CTLs secreted cytolytic pore-forming perforin and granzyme B proteins around tumor cells, leading to the death of tumor cells. The labeled fusion proteins were gradually targeted to the tumor site in an imaging mice model. These results show that VEGF–SEA can serve as a tumor targeting agent and sequester active infiltrating CTLs into the tumor site to kill tumor cells, and could therefore be a potential therapeutical drug for a variety of cancers.

177Lu-DOTA-Bevacizumab: Radioimmunotherapy Agent for Melanoma.

Science.gov (United States)

Camacho, Ximena; Calzada, Victoria; Fernandez, Marcelo; Alonso, Omar; Chammas, Roger; Riva, Eloisa; Gambini, Juan Pablo; Cabral, Pablo

2017-01-01

Vascular endothelial growth factor (VEGF) is one of the classic factors to tumor-induced angiogenesis in several types, including melanoma. Bevacizumab is a humanized monoclonal antibody directed against VEGF. To radiolabel Bevacizumab with 177-Lutetium as a potential radioimmunotherapy agent for melanoma. Bevacizumab was derivatized with DOTA-NHS-ester at 4 ºC for 18 h. DOTABevacizumab was radiolabeled with 177LuCl3 (15 MBq/mg) at 37 ºC for 1 h. The studies were performed in healthy and B16F1 tumor-bearing C57BL/6J mice at 24 and 48 h (n = 5). Scinthigraphic imaging studies were performed at 24 h to determine the radiochemical stability, targeting specificity and pharmacokinetics of the 177Lutetium-labeled antibody. DOTA-Bevacizumab was efficiently labeled with 177LuCl3 at 37 °C. The in-vitro stability of labeled product was optimal over 72 h. In-vivo biodistribution studies showed a high liver and tumor uptake of 177Lu-DOTA-Bevacizumab, with tumor-to-muscle ratios of 11.58 and 6.37 at 24 and 48 h p.i. Scintigraphic imaging of melanoma tumor-bearing C57BL/6J mice showed liver and a high tumor selective uptake of 177Lu-DOTA-Bevacizumab at 24 h. Our results support the potential role of 177Lu-DOTA-Bevacizumab as a novel radioimmunotherapy agent for melanoma. We hope that these novel molecular imaging agents will open the path to new diagnostic and therapeutic strategies for Melanoma disease. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The combined effect of interferon synthesis inductors, radiosensitizing and antitumoral agents on solid tumors

International Nuclear Information System (INIS)

Leonidze, D.L.

1987-01-01

In experiments with mice bearing solid sarcoma 37 a study was conducted on the combined effect of radiation and inductors of endogenous inerferon synthesis (IEIS), together with hyperthermia or together with an alkylating and carbomoilating agent, dimethinur. The effect was estimated by the tumor growth coefficient and by the number of animals with the regressed tumors. Poly I; polyC was not shiown to influence the efficiency of hyperthermia combined with radiation with radiation; dextransulphate and tiloron increased the radiosensitizing effect of hyperthermia. Dimethinur aggravated the effect of radiation, but with IEIS used together with dimethynur and radiation, the response of the tumor increased insignificantly as compared to the effect of IEIS together with radiation

Botanical polysaccharides: macrophage immunomodulation and therapeutic potential.

Science.gov (United States)

Schepetkin, Igor A; Quinn, Mark T

2006-03-01

Botanical polysaccharides exhibit a number of beneficial therapeutic properties, and it is thought that the mechanisms involved in these effects are due to the modulation of innate immunity and, more specifically, macrophage function. In this review, we summarize our current state of understanding of the macrophage modulatory effects of botanical polysaccharides isolated from a wide array of different species of flora, including higher plants, mushrooms, lichens and algae. Overall, the primary effect of botanical polysaccharides is to enhance and/or activate macrophage immune responses, leading to immunomodulation, anti-tumor activity, wound-healing and other therapeutic effects. Furthermore, botanical and microbial polysaccharides bind to common surface receptors and induce similar immunomodulatory responses in macrophages, suggesting that evolutionarily conserved polysaccharide structural features are shared between these organisms. Thus, the evaluation of botanical polysaccharides provides a unique opportunity for the discovery of novel therapeutic agents and adjuvants that exhibit beneficial immunomodulatory properties.

Development of a Tc-99m labeled sigma-2 receptor-specific ligand as a potential breast tumor imaging agent

International Nuclear Information System (INIS)

Choi, Seok-Rye; Yang, Biao; Ploessl, Karl; Chumpradit, Sumalee; Wey, Shiaw-Pyng; Acton, Paul D.; Wheeler, Kenneth; Mach, Robert H.; Kung, Hank F.

2001-01-01

A novel in vivo imaging agent, 99m Tc labeled [(N-[2-((3'-N'-propyl-[3,3,1]aza-bicyclononan-3α-yl)(2''-methoxy-5- methyl-phenylcarbamate) (2-mercaptoethyl)amino)acetyl]-2-aminoethanethiolato] technetium(V) oxide), [ 99m Tc]2, displaying specific binding towards sigma-2 receptors was prepared and characterized. In vitro binding assays showed that the rhenium surrogate of [ 99m Tc]2, Re-2, displayed excellent binding affinity and selectivity towards sigma-2 receptors (K i = 2,723 and 22 nM for sigma-1 and sigma-2 receptor, respectively). Preparation of [ 99m Tc]2 was achieved by heating the S-protected starting material, 1, in the presence of acid, reducing agent (stannous glucoheptonate) and sodium [ 99m Tc]pertechnetate. The lipophilic racemic mixture was successfully prepared in 10 to 50% yield and the radiochemical purity was >98%. Separation of the isomers, peak A and peak B, was successfully achieved by using a chiralpak AD column eluted with an isocratic solvent (n-hexane/isopropanol; 3:1; v/v). The peak A and peak B appear to co-elute with the isomers of the surrogate, Re-2, under the same HPLC condition. Biodistribution studies in tumor bearing mice (mouse mammary adenocarcinoma, cell line 66, which is known to over-express sigma-2 receptors) showed that the racemic [ 99m Tc]2 localized in the tumor. Uptake in the tumor was 2.11, 1.30 and 1.11 %dose/gram at 1, 4 and 8 hr post iv injection, respectively, suggesting good uptake and retention in the tumor cells. The tumor uptake was significantly, but incompletely, blocked (about 25-30% blockage) by co-injection of 'cold' (+)pentazocine or haloperidol (1 mg/Kg). A majority of the radioactivity localized in the tumor tissue was extractable (>60%), and the HPLC analysis showed that it is the original compound, racemic [ 99m Tc]2 (>98% pure). The distribution of the purified peak A and peak B was determined in the same tumor bearing mice at 4 hr post iv injection. The tumor uptake was similar for both isomers

Synthesis and evaluation of novel Tc-99m labeled NGR-containing hexapeptides as tumor imaging agents.

Science.gov (United States)

Kim, Dae-Weung; Kim, Woo Hyoung; Kim, Myoung Hyoun; Kim, Chang Guhn

2015-02-01

Asparagine-glycine-arginine (NGR)-containing peptides targeting aminopeptidase N (APN)/CD13 can be an excellent candidate for targeting ligands in molecular tumor imaging. In this study, we developed two NGR-containing hexapeptides, and evaluated the diagnostic performance of Tc-99m labeled hexapeptides as molecular imaging agents in an HT-1080 fibrosarcoma-bearing murine model. Peptides were synthesized using Fmoc solid-phase peptide synthesis. Radiochemical purity of Tc-99m was evaluated using instant thin-layer chromatography. The uptake of two NGR-containing hexapeptides within HT-1080 cells was evaluated in vitro. In HT-1080 fibrosarcoma tumor-bearing mice, gamma images were acquired. A biodistribution study was performed to calculate percentage of the injected dose per gram of tissue (%ID/g). Two hexapeptides, glutamic acid-cysteine-glycine (ECG)-NGR and NGR-ECG were successfully synthesized. After radiolabeling procedures with Tc-99m, the complexes Tc-99m hexapeptides were prepared in high yield. The uptake of Tc-99m ECG-NGR within the tumor cells had been assured by in vitro studies. The gamma camera imaging in the murine model showed that Tc-99m ECG-NGR was accumulated substantially in the subcutaneously engrafted tumor. However, Tc-99m NGR-ECG was accumulated minimally in the tumor. Two NGR-containing hexapeptides, ECG-NGR and NGR-ECG were developed as molecular imaging agents to target APN/CD13 in HT-1080 fibrosarcoma. Tc-99m ECG-NGR showed a significant uptake in the tumor, and it is a good candidate for tumor imaging. Copyright © 2015 John Wiley & Sons, Ltd.

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

Tetrodotoxin (TTX as a Therapeutic Agent for Pain

Directory of Open Access Journals (Sweden)

Cruz Miguel Cendán

2012-01-01

Full Text Available Tetrodotoxin (TTX is a potent neurotoxin that blocks voltage-gated sodium channels (VGSCs. VGSCs play a critical role in neuronal function under both physiological and pathological conditions. TTX has been extensively used to functionally characterize VGSCs, which can be classified as TTX-sensitive or TTX-resistant channels according to their sensitivity to this toxin. Alterations in the expression and/or function of some specific TTX-sensitive VGSCs have been implicated in a number of chronic pain conditions. The administration of TTX at doses below those that interfere with the generation and conduction of action potentials in normal (non-injured nerves has been used in humans and experimental animals under different pain conditions. These data indicate a role for TTX as a potential therapeutic agent for pain. This review focuses on the preclinical and clinical evidence supporting a potential analgesic role for TTX. In addition, the contribution of specific TTX-sensitive VGSCs to pain is reviewed.

Therapeutic efficacy and microSPECT/CT imaging of {sup 188}Re-DXR-liposome in a C26 murine colon carcinoma solid tumor model

Energy Technology Data Exchange (ETDEWEB)

Chang, Y.-J.; Chang, C.-H.; Yu, C.-Y.; Chang, T.-J.; Chen, L.-C. [Institute of Nuclear Energy Research, Taoyuan, Taiwan (China); Chen, M.-H. [National Health Research Institutes, Miaoli, Taiwan (China); Lee, T.-W. [Institute of Nuclear Energy Research, Taoyuan, Taiwan (China); Ting Gann [National Health Research Institutes, Miaoli, Taiwan (China)], E-mail: gann.ting@msa.hinet.net

2010-01-15

Nanocarriers can selectively target cancer sites and carry payloads, thereby improving diagnostic and therapeutic effectiveness and reducing toxicity. The objective of this study was to investigate the therapeutic efficacy of a new co-delivery radiochemotherapeutics of {sup 188}Re-N,N-bis (2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposomal doxorubicin (DXR) ({sup 188}Re-DXR-liposome) in a C26 murine colon carcinoma solid tumor model. To evaluate the targeting and localization of {sup 188}Re-DXR-liposome in C26 murine tumor-bearing mice, biodistribution, microSPECT/CT imaging and pharmacokinetic studies were performed. The antitumor effect of {sup 188}Re-DXR-liposome was assessed by tumor growth inhibition, survival ratio and histopathological hematoxylin-eosin staining. The tumor target and localization of the nanoliposome delivery radiochemotherapeutics of {sup 188}Re-DXR-liposome were demonstrated in the biodistribution, pharmacokinetics and in vivo nuclear imaging studies. In the study on therapeutic efficacy, the tumor-bearing mice treated with bimodality radiochemotherapeutics of {sup 188}Re-DXR-liposome showed better mean tumor growth inhibition rate (MGI) and longer median survival time (MGI=0.048; 74 days) than those treated with radiotherapeutics of {sup 188}Re-liposome (MGI=0.134; 60 days) and chemotherapeutics of Lipo-Dox (MGI=0.413; 38 days). The synergistic tumor regression effect was observed with the combination index (CI) exceeding 1 (CI=1.145) for co-delivery radiochemotherapeutics of {sup 188}Re-DXR-liposome. Two (25%) of the mice treated with radiochemotherapeutics were completely cured after 120 days. The therapeutic efficacy of radiotherapeutics of {sup 188}Re-liposome and the synergistic effect of the combination radiochemotherapeutics of {sup 188}Re-DXR-liposome have been demonstrated in a C26 murine solid tumor animal model, which pointed to the potential benefit and promise of the co-delivery of

Contributions of nuclear medicine to the therapy of malignant tumors

Energy Technology Data Exchange (ETDEWEB)

Feinendegen, L.E. (Forschungszentrum Juelich GmbH (Germany). Inst. fuer Medizin Duesseldorf Univ. (Germany). Nuklearmedizinische Klinik)

1991-11-01

The diagnostic and therapeutic application of radionuclides on oncology has led to an increased efficiency in the treatment of malignant tumors. - Regarding diagnosis, measuring metabolic reactions in tumor tissue, especially by positron emission tomography, opened the potential for assaying tumor response to different treatment modalities and thus eventually for tailoring effective treatment of a given tumor in the individual patient. - Regarding treatment, attention is given to the choice of the radionuclide for optimal deposition of the desired radiation in tumor cells avoiding exposure of normal cells; in this context microdosimetric considerations are essential with respect to {beta}-emitters, {alpha}-emitters, the Auger-effect and neutron capture therapy. Examples of therapeutic uses of radionuclides in the inorganic form are 131-I for thyroid cancer and 32-P for polycythemia vera; organically bound radionuclides are employed with precursors for tumor cell metabolism or with receptor seeking agents, such as MIBG and monoclonal antibodies which presently enjoy a particular interest and bear great promise. Stable nuclides, if property accumulated within tumors, may be activated for therapy in situ, for example by thermal neutrons, as in neutron capture therapy using the 10-B (n, {alpha})7-Li reaction. - Treatment planning and execution with radionuclides have gained momentum over the past decade, yet much more needs to be done. (orig.).

Targeted radionuclide therapy for solid tumors: An overview

International Nuclear Information System (INIS)

De Nardo, Sally J.; De Nardo, Gerald L.

2006-01-01

Although radioimmunotherapy (RIT) has been effective in non-Hodgkin's lymphoma (NHL) as a single agent, solid tumors have shown less clinically significant therapeutic response to RIT alone. The clinical impact of RIT or other forms of targeted radionuclide therapy for solid tumors depends on the development of a high therapeutic index (TI) for the tumor vs. normal tissue effect, and the implementation of RIT as part of synergistic combined modality therapy (CMRIT). Preclinical and clinical studies have provided a wealth of information, and new prototypes or paradigms have shed light on future possibilities in many instances. Evidence suggests that combination and sequencing of RIT in CMRIT appropriately can provide effective treatment for many solid tumors. Vascular targets provide RIT enhancement opportunities and nanoparticles may prove to be effective carriers for RIT combined with intracellular drug delivery or alternating magnetic frequency (AMF) induced thermal tumor necrosis. The sequence and timing of combined modality treatments will be of critical importance to achieve synergy for therapy while minimizing toxicity. Fortunately, the radionuclide used for RIT also provides a signal useful for nondestructive quantitation of the influence of sequence and timing of CMRIT on events in animals and patients. This can be readily accomplished clinically using quantitative high-resolution imaging (e.g., positron emission tomography [PET])

Assessment of a novel VEGF targeted agent using patient-derived tumor tissue xenograft models of colon carcinoma with lymphatic and hepatic metastases.

Directory of Open Access Journals (Sweden)

Ketao Jin

Full Text Available The lack of appropriate tumor models of primary tumors and corresponding metastases that can reliably predict for response to anticancer agents remains a major deficiency in the clinical practice of cancer therapy. It was the aim of our study to establish patient-derived tumor tissue (PDTT xenograft models of colon carcinoma with lymphatic and hepatic metastases useful for testing of novel molecularly targeted agents. PDTT of primary colon carcinoma, lymphatic and hepatic metastases were used to create xenograft models. Hematoxylin and eosin staining, immunohistochemical staining, genome-wide gene expression analysis, pyrosequencing, qRT-PCR, and western blotting were used to determine the biological stability of the xenografts during serial transplantation compared with the original tumor tissues. Early passages of the PDTT xenograft models of primary colon carcinoma, lymphatic and hepatic metastases revealed a high degree of similarity with the original clinical tumor samples with regard to histology, immunohistochemistry, genes expression, and mutation status as well as mRNA expression. After we have ascertained that these xenografts models retained similar histopathological features and molecular signatures as the original tumors, drug sensitivities of the xenografts to a novel VEGF targeted agent, FP3 was evaluated. In this study, PDTT xenograft models of colon carcinoma with lymphatic and hepatic metastasis have been successfully established. They provide appropriate models for testing of novel molecularly targeted agents.

Advances in Virus-Directed Therapeutics against Epstein-Barr Virus-Associated Malignancies

Directory of Open Access Journals (Sweden)

Sajal K. Ghosh

2012-01-01

Full Text Available Epstein-Barr virus (EBV is the causal agent in the etiology of Burkitt’s lymphoma and nasopharyngeal carcinoma and is also associated with multiple human malignancies, including Hodgkin’s and non-Hodgkin’s lymphoma, and posttransplantation lymphoproliferative disease, as well as sporadic cancers of other tissues. A causal relationship of EBV to these latter malignancies remains controversial, although the episomic EBV genome in most of these cancers is clonal, suggesting infection very early in the development of the tumor and a possible role for EBV in the genesis of these diseases. Furthermore, the prognosis of these tumors is invariably poor when EBV is present, compared to their EBV-negative counterparts. The physical presence of EBV in these tumors represents a potential “tumor-specific” target for therapeutic approaches. While treatment options for other types of herpesvirus infections have evolved and improved over the last two decades, however, therapies directed at EBV have lagged. A major constraint to pharmacological intervention is the shift from lytic infection to a latent pattern of gene expression, which persists in those tumors associated with the virus. In this paper we provide a brief account of new virus-targeted therapeutic approaches against EBV-associated malignancies.

TIE2-expressing macrophages limit the therapeutic efficacy of the vascular-disrupting agent combretastatin A4 phosphate in mice

Science.gov (United States)

Welford, Abigail F.; Biziato, Daniela; Coffelt, Seth B.; Nucera, Silvia; Fisher, Matthew; Pucci, Ferdinando; Di Serio, Clelia; Naldini, Luigi; De Palma, Michele; Tozer, Gillian M.; Lewis, Claire E.

2011-01-01

Vascular-disrupting agents (VDAs) such as combretastatin A4 phosphate (CA4P) selectively disrupt blood vessels in tumors and induce tumor necrosis. However, tumors rapidly repopulate after treatment with such compounds. Here, we show that CA4P-induced vessel narrowing, hypoxia, and hemorrhagic necrosis in murine mammary tumors were accompanied by elevated tumor levels of the chemokine CXCL12 and infiltration by proangiogenic TIE2-expressing macrophages (TEMs). Inhibiting TEM recruitment to CA4P-treated tumors either by interfering pharmacologically with the CXCL12/CXCR4 axis or by genetically depleting TEMs in tumor-bearing mice markedly increased the efficacy of CA4P treatment. These data suggest that TEMs limit VDA-induced tumor injury and represent a potential target for improving the clinical efficacy of VDA-based therapies. PMID:21490397

Combination Therapy With Histone Deacetylase Inhibitors (HDACi for the Treatment of Cancer: Achieving the Full Therapeutic Potential of HDACi

Directory of Open Access Journals (Sweden)

Amila Suraweera

2018-03-01

Full Text Available Genetic and epigenetic changes in DNA are involved in cancer development and tumor progression. Histone deacetylases (HDACs are key regulators of gene expression that act as transcriptional repressors by removing acetyl groups from histones. HDACs are dysregulated in many cancers, making them a therapeutic target for the treatment of cancer. Histone deacetylase inhibitors (HDACi, a novel class of small-molecular therapeutics, are now approved by the Food and Drug Administration as anticancer agents. While they have shown great promise, resistance to HDACi is often observed and furthermore, HDACi have shown limited success in treating solid tumors. The combination of HDACi with standard chemotherapeutic drugs has demonstrated promising anticancer effects in both preclinical and clinical studies. In this review, we summarize the research thus far on HDACi in combination therapy, with other anticancer agents and their translation into preclinical and clinical studies. We additionally highlight the side effects associated with HDACi in cancer therapy and discuss potential biomarkers to either select or predict a patient’s response to these agents, in order to limit the off-target toxicity associated with HDACi.

Targeting Angiogenesis and Tumor Microenvironment in Metastatic Colorectal Cancer: Role of Aflibercept

Directory of Open Access Journals (Sweden)

Guido Giordano

2014-01-01

Full Text Available In the last decades, we have progressively observed an improvement in therapeutic options for metastatic colorectal cancer (mCRC treatment with a progressive prolongation of survival. mCRC prognosis still remains poor with low percentage of 5-year survival. Targeted agents have improved results obtained with standard chemotherapy. Angiogenesis plays a crucial role in colorectal cancer growth, proliferation, and metastasization and it has been investigated as a potential target for mCRC treatment. Accordingly, novel antiangiogenic targeted agents bevacizumab, regorafenib, and aflibercept have been approved for mCRC treatment as the result of several phase III randomized trials. The development of a tumor permissive microenvironment via the aberrant expression by tumor cells of paracrine factors alters the tumor-stroma interactions inducing an expansion of proangiogenic signals. Recently, the VELOUR study showed that addition of aflibercept to FOLFIRI regimen as a second-line therapy for mCRC improved significantly OS, PFS, and RR. This molecule represents a valid second-line therapeutic option and its peculiar ability to interfere with placental growth factor (PlGF/vascular endothelial growth factor receptor 1 (VEGFR1 axis makes it effective in targeting angiogenesis, inflammatory cells and in overcoming resistances to anti-angiogenic first-line treatment. Here, we discuss about Aflibercept peculiar ability to interfere with tumor microenvironment and angiogenic pathway.

Cell targeting peptides as smart ligands for targeting of therapeutic or diagnostic agents: a systematic review.

Science.gov (United States)

Mousavizadeh, Ali; Jabbari, Ali; Akrami, Mohammad; Bardania, Hassan

2017-10-01

Cell targeting peptides (CTP) are small peptides which have high affinity and specificity to a cell or tissue targets. They are typically identified by using phage display and chemical synthetic peptide library methods. CTPs have attracted considerable attention as a new class of ligands to delivery specifically therapeutic and diagnostic agents, because of the fact they have several advantages including easy synthesis, smaller physical sizes, lower immunogenicity and cytotoxicity and their simple and better conjugation to nano-carriers and therapeutic or diagnostic agents compared to conventional antibodies. In this systematic review, we will focus on the basic concepts concerning the use of cell-targeting peptides (CTPs), following the approaches of selecting them from peptide libraries. We discuss several developed strategies for cell-specific delivery of different cargos by CTPs, which are designed for drug delivery and diagnostic applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Quantitative Molecular Imaging with a Single Gd-Based Contrast Agent Reveals Specific Tumor Binding and Retention in Vivo.

Science.gov (United States)

Johansen, Mette L; Gao, Ying; Hutnick, Melanie A; Craig, Sonya E L; Pokorski, Jonathan K; Flask, Chris A; Brady-Kalnay, Susann M

2017-06-06

Magnetic resonance imaging (MRI) has become an indispensable tool in the diagnosis and treatment of many diseases, especially cancer. However, the poor sensitivity of MRI relative to other imaging modalities, such as PET, has hindered the development and clinical use of molecular MRI contrast agents that could provide vital diagnostic information by specifically locating a molecular target altered in the disease process. This work describes the specific and sustained in vivo binding and retention of a protein tyrosine phosphatase mu (PTPμ)-targeted, molecular magnetic resonance (MR) contrast agent with a single gadolinium (Gd) chelate using a quantitative MRI T 1 mapping technique in glioma xenografts. Quantitative T 1 mapping is an imaging method used to measure the longitudinal relaxation time, the T 1 relaxation time, of protons in a magnetic field after excitation by a radiofrequency pulse. T 1 relaxation times can in turn be used to calculate the concentration of a gadolinium-containing contrast agent in a region of interest, thereby allowing the retention or clearance of an agent to be quantified. In this context, retention is a measure of molecular contrast agent binding. Using conventional peptide chemistry, a PTPμ-targeted peptide was linked to a chelator that had been conjugated to a lysine residue. Following complexation with Gd, this PTPμ-targeted molecular contrast agent containing a single Gd ion showed significant tumor enhancement and a sustained increase in Gd concentration in both heterotopic and orthotopic tumors using dynamic quantitative MRI. This single Gd-containing PTPμ agent was more effective than our previous version with three Gd ions. Differences between nonspecific and specific agents, due to specific tumor binding, can be determined within the first 30 min after agent administration by examining clearance rates. This more facile chemistry, when combined with quantitative MR techniques, allows for widespread adoption by academic

Monitoring early tumor response to drug therapy with diffuse optical tomography

Science.gov (United States)

Flexman, Molly L.; Vlachos, Fotios; Kim, Hyun Keol; Sirsi, Shashank R.; Huang, Jianzhong; Hernandez, Sonia L.; Johung, Tessa B.; Gander, Jeffrey W.; Reichstein, Ari R.; Lampl, Brooke S.; Wang, Antai; Borden, Mark A.; Yamashiro, Darrell J.; Kandel, Jessica J.; Hielscher, Andreas H.

2012-01-01

Although anti-angiogenic agents have shown promise as cancer therapeutics, their efficacy varies between tumor types and individual patients. Providing patient-specific metrics through rapid noninvasive imaging can help tailor drug treatment by optimizing dosages, timing of drug cycles, and duration of therapy--thereby reducing toxicity and cost and improving patient outcome. Diffuse optical tomography (DOT) is a noninvasive three-dimensional imaging modality that has been shown to capture physiologic changes in tumors through visualization of oxygenated, deoxygenated, and total hemoglobin concentrations, using non-ionizing radiation with near-infrared light. We employed a small animal model to ascertain if tumor response to bevacizumab (BV), an anti-angiogenic agent that targets vascular endothelial growth factor (VEGF), could be detected at early time points using DOT. We detected a significant decrease in total hemoglobin levels as soon as one day after BV treatment in responder xenograft tumors (SK-NEP-1), but not in SK-NEP-1 control tumors or in non-responder control or BV-treated NGP tumors. These results are confirmed by magnetic resonance imaging T2 relaxometry and lectin perfusion studies. Noninvasive DOT imaging may allow for earlier and more effective control of anti-angiogenic therapy.

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.

A multiplexed microfluidic system for evaluation of dynamics of immune-tumor interactions.

Science.gov (United States)

Moore, N; Doty, D; Zielstorff, M; Kariv, I; Moy, L Y; Gimbel, A; Chevillet, J R; Lowry, N; Santos, J; Mott, V; Kratchman, L; Lau, T; Addona, G; Chen, H; Borenstein, J T

2018-05-25

Recapitulation of the tumor microenvironment is critical for probing mechanisms involved in cancer, and for evaluating the tumor-killing potential of chemotherapeutic agents, targeted therapies and immunotherapies. Microfluidic devices have emerged as valuable tools for both mechanistic studies and for preclinical evaluation of therapeutic agents, due to their ability to precisely control drug concentrations and gradients of oxygen and other species in a scalable and potentially high throughput manner. Most existing in vitro microfluidic cancer models are comprised of cultured cancer cells embedded in a physiologically relevant matrix, collocated with vascular-like structures. However, the recent emergence of immune checkpoint inhibitors (ICI) as a powerful therapeutic modality against many cancers has created a need for preclinical in vitro models that accommodate interactions between tumors and immune cells, particularly for assessment of unprocessed tumor fragments harvested directly from patient biopsies. Here we report on a microfluidic model, termed EVIDENT (ex vivo immuno-oncology dynamic environment for tumor biopsies), that accommodates up to 12 separate tumor biopsy fragments interacting with flowing tumor-infiltrating lymphocytes (TILs) in a dynamic microenvironment. Flow control is achieved with a single pump in a simple and scalable configuration, and the entire system is constructed using low-sorption materials, addressing two principal concerns with existing microfluidic cancer models. The system sustains tumor fragments for multiple days, and permits real-time, high-resolution imaging of the interaction between autologous TILs and tumor fragments, enabling mapping of TIL-mediated tumor killing and testing of various ICI treatments versus tumor response. Custom image analytic algorithms based on machine learning reported here provide automated and quantitative assessment of experimental results. Initial studies indicate that the system is capable of

DNA interstrand cross-link repair: understanding role of Fanconi anemia pathway and therapeutic implications.

Science.gov (United States)

Shukla, Pallavi; Solanki, Avani; Ghosh, Kanjaksha; Vundinti, Babu Rao

2013-11-01

Interstrand cross-links (ICLs) are extremely toxic DNA lesions that prevent DNA double-helix separation due to the irreversible covalent linkage binding of some agents on DNA strands. Agents that induce these ICLs are thus widely used as chemotherapeutic drugs but may also lead to tumor growth. Fanconi anemia (FA) is a rare genetic disorder that leads to ICL sensitivity. This review provides update on current understanding of the role of FA proteins in repairing ICLs at various stages of cell cycle. We also discuss link between DNA cross-link genotoxicity caused by aldehydes in FA pathway. Besides this, we summarize various ICL agents that act as drugs to treat different types of tumors and highlight strategies for modulating ICL sensitivity for therapeutic interventions that may be helpful in controlling cancer and life-threatening disease, FA. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Extravascular red blood cells and hemoglobin promote tumor growth and therapeutic resistance as endogenous danger signals.

Science.gov (United States)

Yin, Tao; He, Sisi; Liu, Xiaoling; Jiang, Wei; Ye, Tinghong; Lin, Ziqiang; Sang, Yaxiong; Su, Chao; Wan, Yang; Shen, Guobo; Ma, Xuelei; Yu, Min; Guo, Fuchun; Liu, Yanyang; Li, Ling; Hu, Qiancheng; Wang, Yongsheng; Wei, Yuquan

2015-01-01

Hemorrhage is a common clinical manifestation in patients with cancer. Intratumor hemorrhage has been demonstrated to be a poor prognostic factor for cancer patients. In this study, we investigated the role of RBCs and hemoglobin (Hb) in the process of tumor progression and therapeutical response. RBCs and Hb potently promoted tumor cell proliferation and syngenic tumor growth. RBCs and Hb activated the reactive oxygen species-NF-κB pathway in both tumor cells and macrophages. RBCs and Hb also induced chemoresistance mediated, in part, by upregulating ABCB1 gene expression. Tumor growth induced by RBCs was accompanied by an inflammatory signature, increased tumor vasculature, and influx of M2 macrophages. In both the peritoneal cavity and tumor microenvironment, extravascular RBCs rapidly recruited monocyte-macrophages into the lesion sites. In addition, RBCs and Hb increased several nucleotide-binding oligomerization domain-like receptors' expression and induced IL-1β release. Our results provide novel insights into the protumor function of RBCs and Hb as endogenous danger signals, which can promote tumor cell proliferation, macrophage recruitment, and polarization. Hemorrhage may represent a useful prognostic factor for cancer patients because of its role in tumor promotion and chemoresistance. Copyright © 2014 by The American Association of Immunologists, Inc.

Dynamics of melanoma tumor therapy with vesicular stomatitis virus: explaining the variability in outcomes using mathematical modeling.

Science.gov (United States)

Rommelfanger, D M; Offord, C P; Dev, J; Bajzer, Z; Vile, R G; Dingli, D

2012-05-01

Tumor selective, replication competent viruses are being tested for cancer gene therapy. This approach introduces a new therapeutic paradigm due to potential replication of the therapeutic agent and induction of a tumor-specific immune response. However, the experimental outcomes are quite variable, even when studies utilize highly inbred strains of mice and the same cell line and virus. Recognizing that virotherapy is an exercise in population dynamics, we utilize mathematical modeling to understand the variable outcomes observed when B16ova malignant melanoma tumors are treated with vesicular stomatitis virus in syngeneic, fully immunocompetent mice. We show how variability in the initial tumor size and the actual amount of virus delivered to the tumor have critical roles on the outcome of therapy. Virotherapy works best when tumors are small, and a robust innate immune response can lead to superior tumor control. Strategies that reduce tumor burden without suppressing the immune response and methods that maximize the amount of virus delivered to the tumor should optimize tumor control in this model system.

Immunological effects of hypomethylating agents.

Science.gov (United States)

Lindblad, Katherine E; Goswami, Meghali; Hourigan, Christopher S; Oetjen, Karolyn A

2017-08-01

Epigenetic changes resulting from aberrant methylation patterns are a recurrent observation in hematologic malignancies. Hypomethylating agents have a well-established role in the management of patients with high-risk myelodysplastic syndrome or acute myeloid leukemia. In addition to the direct effects of hypomethylating agents on cancer cells, there are several lines of evidence indicating a role for immune-mediated anti-tumor benefits from hypomethylating therapy. Areas covered: We reviewed the clinical and basic science literature for the effects of hypomethylating agents, including the most commonly utilized therapeutics azacitidine and decitabine, on immune cell subsets. We summarized the effects of hypomethylating agents on the frequency and function of natural killer cells, T cells, and dendritic cells. In particular, we highlight the effects of hypomethylating agents on expression of immune checkpoint inhibitors, leukemia-associated antigens, and endogenous retroviral elements. Expert commentary: In vitro and ex vivo studies indicate mixed effects on the function of natural killer, dendritic cells and T cells following treatment with hypomethylating agents. Clinical correlates of immune function have suggested that hypomethylating agents have immunomodulatory functions with the potential to synergize with immune checkpoint therapy for the treatment of hematologic malignancy, and has become an active area of clinical research.

Therapeutic peptides for cancer therapy. Part I - peptide inhibitors of signal transduction cascades.

Science.gov (United States)

Bidwell, Gene L; Raucher, Drazen

2009-10-01

Therapeutic peptides have great potential as anticancer agents owing to their ease of rational design and target specificity. However, their utility in vivo is limited by low stability and poor tumor penetration. The authors review the development of peptide inhibitors with potential for cancer therapy. Peptides that inhibit signal transduction cascades are discussed. The authors searched Medline for articles concerning the development of therapeutic peptides and their delivery. Given our current knowledge of protein sequences, structures and interaction interfaces, therapeutic peptides that inhibit interactions of interest are easily designed. These peptides are advantageous because they are highly specific for the interaction of interest, and they are much more easily developed than small molecule inhibitors of the same interactions. The main hurdle to application of peptides for cancer therapy is their poor pharmacokinetic and biodistribution parameters. Therefore, successful development of peptide delivery vectors could potentially make possible the use of this new and very promising class of anticancer agents.

Newly designed Tc(V)-99m dimercaptosuccinic acid: An agent of high accuracy for the diagnosis of head and neck and soft tissue tumors

International Nuclear Information System (INIS)

Endo, K.; Ohta, H.; Sakahara, H.; Nakashima, T.; Masuda, H.; Horiuchi, K.; Yokoyama, A.; Torizuka, K.

1984-01-01

Being aware of the ideal nuclear properties of Tc-99m, interest has been focused on the design of (+5) oxidation state Tc-99m dimercaptosuccinic acid (DMSA) as a tumor seeking agent. This Tc(V)-99m DMSA holding a TcO/sup 3-//sub 4/ core, alike PO/sup 3-//sub 4/, with competent characteristics for tumor uptake, had a different distribution behavior from the well-known renal scanning agent; Tc(III)-99m DMSA. Basic studies, carried out in vitro and in vivo with Ehrlich tumor cells or bearing mice, clearly substantiated its great potentiality for clinical use. Therefore, 193 untreated patients with histologically proven diagnosis (132 malignant and 61 benign tumors) were evaluated. In 53 primary head and neck tumor (mainly squamous cell carcinomas and plemorphic adenomas or abscess), its sensitivity and specificity was 78% and 87%, as opposed to Ga-67 citrate of 85% and 51% respectively. In 18 malignant soft tissue tumors, all but one (94%) showed significant uptake of Tc(V)-99m DMSA, while Ga-67 was positive in only 60% of these cases. The specificity of both agents was 74% and 86%, respectively. However in lung and abdominal tumors, lymphomas, melanomas and inflammatory lesions, the sensitivity was poor of less than 40%. Also negative were scans in most thyroid cancers, however, 5 patients with medullary thyroid cancers, were all positive with Tc(V)-99m DMSA and was useful follow patients after surgery. Thus, a different uptake mechanism for this agent could be visualized. The authors conclude that Tc(V)-99m DMSA provided a good basis for its clinical application as a tumor imaging agent, mainly in head and neck squamous cell carcinomas, medullary thyroid cancers and soft tissue tumors

The reason for discontinuation of the first tumor necrosis factor (TNF) blocking agent does not influence the effect of a second TNF blocking agent in patients with rheumatoid arthritis.

NARCIS (Netherlands)

Blom, M.; Kievit, W.; Fransen, J.; Kuper, I.H.; Broeder, A. den; Gendt, C.M. de; Jansen, T.L.Th.A.; Brus, H.L.; Laar, M.A. van der; Riel, P.L.C.M. van

2009-01-01

OBJECTIVE: To investigate whether the reason for discontinuation of the first tumor necrosis factor (TNF) blocking agent influences the effect of a second TNF blocking agent. METHODS: Data were used from 2 Dutch registries including patients with rheumatoid arthritis (RA) treated with TNF blocking

The reason for discontinuation of the first tumor necrosis factor (TNF) blocking agent does not influence the effect of a second TNF blocking agent in patients with rheumatoid arthritis

NARCIS (Netherlands)

Blom, Marlies; Kievit, Wietske; Fransen, Jaap; Kuper, Ina H.; den Broeder, Alfons A.; De Gendt, Carla M.A.; Jansen, Tim L.; Brus, Herman L.M.; van de Laar, Mart A.F.J.; van Riel, Piet L.C.M.

2009-01-01

OBJECTIVE:To investigate whether the reason for discontinuation of the first tumor necrosis factor (TNF) blocking agent influences the effect of a second TNF blocking agent. METHODS:Data were used from 2 Dutch registries including patients with rheumatoid arthritis (RA) treated with TNF blocking

Gd-labeled glycol chitosan as a pH-responsive magnetic resonance imaging agent for detecting acidic tumor microenvironments.

Science.gov (United States)

Nwe, Kido; Huang, Ching-Hui; Tsourkas, Andrew

2013-10-24

Neoplastic lesions can create a hostile tumor microenvironment with low extracellular pH. It is commonly believed that these conditions can contribute to tumor progression as well as resistance to therapy. We report the development and characterization of a pH-responsive magnetic resonance imaging contrast agent for imaging the acidic tumor microenvironment. The preparation included the conjugation of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid 1-(2,5-dioxo-1-pyrrolidinyl) ester (DOTA-NHS) to the surface of a water-soluble glycol chitosan (GC) polymer, which contains pH-titrable primary amines, followed by gadolinium complexation (GC-NH2-GdDOTA). GC-NH2-GdDOTA had a chelate-to-polymer ratio of approximately1:24 and a molar relaxivity of 9.1 mM(-1) s(-1). GC-NH2-GdDOTA demonstrated pH-dependent cellular association in vitro compared to the control. It also generated a 2.4-fold enhancement in signal in tumor-bearing mice 2 h postinjection. These findings suggest that glycol chitosan coupled with contrast agents can provide important diagnostic information about the tumor microenvironment.

Immune Consequences of Decreasing Tumor Vasculature with Antiangiogenic Tyrosine Kinase Inhibitors in Combination with Therapeutic Vaccines

Science.gov (United States)

Farsaci, Benedetto; Donahue, Renee N.; Coplin, Michael A.; Grenga, Italia; Lepone, Lauren M.; Molinolo, Alfredo A.; Hodge, James W.

2014-01-01

This study investigated the effects on the tumor microenvironment of combining antiangiogenic tyrosine kinase inhibitors (TKI) with therapeutic vaccines, and in particular, how vascular changes affect tumor-infiltrating immune cells. We conducted studies using a TKI (sunitinib or sorafenib) in combination with recombinant vaccines in 2 murine tumor models: colon carcinoma (MC38-CEA) and breast cancer (4T1). Tumor vasculature was measured by immunohistochemistry using 3 endothelial cell markers: CD31 (mature), CD105 (immature/proliferating), and CD11b (monocytic). We assessed oxygenation, tight junctions, compactness, and pressure within tumors, along with the frequency and phenotype of tumor-infiltrating T lymphocytes (TIL), myeloid-derived suppressor cells (MDSC), and tumor-associated macrophages (TAM) following treatment with antiangiogenic TKIs alone, vaccine alone, or the combination of a TKI with vaccine. The combined regimen decreased tumor vasculature, compactness, tight junctions, and pressure, leading to vascular normalization and increased tumor oxygenation. This combination therapy also increased TILs, including tumor antigen-specific CD8 T cells, and elevated the expression of activation markers FAS-L, CXCL-9, CD31, and CD105 in MDSCs and TAMs, leading to reduced tumor volumes and an increase in the number of tumor-free animals. The improved antitumor activity induced by combining antiangiogenic TKIs with vaccine may be the result of activated lymphoid and myeloid cells in the tumor microenvironment, resulting from vascular normalization, decreased tumor-cell density, and the consequent improvement in vascular perfusion and oxygenation. Therapies that alter tumor architecture can thus have a dramatic impact on the effectiveness of cancer immunotherapy. PMID:25092771

[Fluorine-18 labeled androgens and progestins; imaging agents for tumors of prostate and breast]: Technical progress report, February 1, 1987-January 31, 1988

International Nuclear Information System (INIS)

Katzenellenbogen, J.A.

1987-01-01

This project develops fluorine-18 labeled steroids that possess high binding affinity and selectivity for androgen and progesterone receptors and can be used as positron-emission tomographic imaging agents for prostate tumors and breast tumors, respectively. These novel diagnostic agents may enable an accurate estimation of tumor dissemination, such as metastasis of prostate cancer and lymph node involvement of breast cancer, and an in vivo determination of the endocrine responsiveness of these tumors. They will provide essential information for the selection of alternative therapies thereby improving the management of prostate and breast cancer patients. 14 refs., 1 tab

The vascular disrupting agent ZD6126 shows increased antitumor efficacy and enhanced radiation response in large, advanced tumors

International Nuclear Information System (INIS)

Siemann, Dietmar W.; Rojiani, Amyn M.

2005-01-01

Purpose: ZD6126 is a vascular-targeting agent that induces selective effects on the morphology of proliferating and immature endothelial cells by disrupting the tubulin cytoskeleton. The efficacy of ZD6126 was investigated in large vs. small tumors in a variety of animal models. Methods and Materials: Three rodent tumor models (KHT, SCCVII, RIF-1) and three human tumor xenografts (Caki-1, KSY-1, SKBR3) were used. Mice bearing leg tumors ranging in size from 0.1-2.0 g were injected intraperitoneally with a single 150 mg/kg dose of ZD6126. The response was assessed by morphologic and morphometric means as well as an in vivo to in vitro clonogenic cell survival assay. To examine the impact of tumor size on the extent of enhancement of radiation efficacy by ZD6126, KHT sarcomas of three different sizes were irradiated locally with a range of radiation doses, and cell survival was determined. Results: All rodent tumors and human tumor xenografts evaluated showed a strong correlation between increasing tumor size and treatment effect as determined by clonogenic cell survival. Detailed evaluation of KHT sarcomas treated with ZD6126 showed a reduction in patent tumor blood vessels that was ∼20% in small ( 90% in large (>1.0 g) tumors. Histologic assessment revealed that the extent of tumor necrosis after ZD6126 treatment, although minimal in small KHT sarcomas, became more extensive with increasing tumor size. Clonogenic cell survival after ZD6126 exposure showed a decrease in tumor surviving fraction from approximately 3 x 10 -1 to 1 x 10 -4 with increasing tumor size. When combined with radiotherapy, ZD6126 treatment resulted in little enhancement of the antitumor effect of radiation in small (<0.3 g) tumors but marked increases in cell kill in tumors larger than 1.0 g. Conclusions: Because bulky neoplastic disease is typically the most difficult to manage, the present findings provide further support for the continued development of vascular disrupting agents such as

Inducing death in tumor cells: roles of the inhibitor of apoptosis proteins.

Science.gov (United States)

Finlay, Darren; Teriete, Peter; Vamos, Mitchell; Cosford, Nicholas D P; Vuori, Kristiina

2017-01-01

The heterogeneous group of diseases collectively termed cancer results not just from aberrant cellular proliferation but also from a lack of accompanying homeostatic cell death. Indeed, cancer cells regularly acquire resistance to programmed cell death, or apoptosis, which not only supports cancer progression but also leads to resistance to therapeutic agents. Thus, various approaches have been undertaken in order to induce apoptosis in tumor cells for therapeutic purposes. Here, we will focus our discussion on agents that directly affect the apoptotic machinery itself rather than on drugs that induce apoptosis in tumor cells indirectly, such as by DNA damage or kinase dependency inhibition. As the roles of the Bcl-2 family have been extensively studied and reviewed recently, we will focus in this review specifically on the inhibitor of apoptosis protein (IAP) family. IAPs are a disparate group of proteins that all contain a baculovirus IAP repeat domain, which is important for the inhibition of apoptosis in some, but not all, family members. We describe each of the family members with respect to their structural and functional similarities and differences and their respective roles in cancer. Finally, we also review the current state of IAPs as targets for anti-cancer therapeutics and discuss the current clinical state of IAP antagonists.

Targeted Therapeutic Nanoparticles: An Immense Promise to Fight against Cancer

Directory of Open Access Journals (Sweden)

Sheikh Tasnim Jahan

2017-01-01

Full Text Available In nanomedicine, targeted therapeutic nanoparticle (NP is a virtual outcome of nanotechnology taking the advantage of cancer propagation pattern. Tying up all elements such as therapeutic or imaging agent, targeting ligand, and cross-linking agent with the NPs is the key concept to deliver the payload selectively where it intends to reach. The microenvironment of tumor tissues in lymphatic vessels can also help targeted NPs to achieve their anticipated accumulation depending on the formulation objectives. This review accumulates the application of poly(lactic-co-glycolic acid (PLGA and polyethylene glycol (PEG based NP systems, with a specific perspective in cancer. Nowadays, PLGA, PEG, or their combinations are the mostly used polymers to serve the purpose of targeted therapeutic NPs. Their unique physicochemical properties along with their biological activities are also discussed. Depending on the biological effects from parameters associated with existing NPs, several advantages and limitations have been explored in teaming up all the essential facts to give birth to targeted therapeutic NPs. Therefore, the current article will provide a comprehensive review of various approaches to fabricate a targeted system to achieve appropriate physicochemical properties. Based on such findings, researchers can realize the benefits and challenges for the next generation of delivery systems.

Blockade of the ERK pathway enhances the therapeutic efficacy of the histone deacetylase inhibitor MS-275 in human tumor xenograft models

Energy Technology Data Exchange (ETDEWEB)

Sakamoto, Toshiaki; Ozaki, Kei-ichi; Fujio, Kohsuke; Kajikawa, Shu-hei [Laboratory of Cell Regulation, Department of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Uesato, Shin-ichi [Department of Biotechnology, Faculty of Engineering, Kansai University, Osaka 564-8680 (Japan); Watanabe, Kazushi [Proubase Technology Inc., Kanagawa 211-0063 (Japan); Tanimura, Susumu [Laboratory of Cell Regulation, Department of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Koji, Takehiko [Department of Histology and Cell Biology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8523 (Japan); Kohno, Michiaki, E-mail: kohnom@nagasaki-u.ac.jp [Laboratory of Cell Regulation, Department of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Proubase Technology Inc., Kanagawa 211-0063 (Japan); Kyoto University Graduate School of Pharmaceutical Sciences, Kyoto 606-8501 (Japan)

2013-04-19

Highlights: •Blockade of the ERK pathway enhances the anticancer efficacy of HDAC inhibitors. •MEK inhibitors sensitize human tumor xenografts to HDAC inhibitor cytotoxicity. •Such the enhanced efficacy is achieved by a transient blockade of the ERK pathway. •This drug combination provides a promising therapeutic strategy for cancer patients. -- Abstract: The ERK pathway is up-regulated in various human cancers and represents a prime target for mechanism-based approaches to cancer treatment. Specific blockade of the ERK pathway alone induces mostly cytostatic rather than pro-apoptotic effects, however, resulting in a limited therapeutic efficacy of the ERK kinase (MEK) inhibitors. We previously showed that MEK inhibitors markedly enhance the ability of histone deacetylase (HDAC) inhibitors to induce apoptosis in tumor cells with constitutive ERK pathway activation in vitro. To evaluate the therapeutic efficacy of such drug combinations, we administered the MEK inhibitor PD184352 or AZD6244 together with the HDAC inhibitor MS-275 in nude mice harboring HT-29 or H1650 xenografts. Co-administration of the MEK inhibitor markedly sensitized the human xenografts to MS-275 cytotoxicity. A dose of MS-275 that alone showed only moderate cytotoxicity thus suppressed the growth of tumor xenografts almost completely as well as induced a marked reduction in tumor cellularity when administered with PD184352 or AZD6244. The combination of the two types of inhibitor also induced marked oxidative stress, which appeared to result in DNA damage and massive cell death, specifically in the tumor xenografts. The enhanced therapeutic efficacy of the drug combination was achieved by a relatively transient blockade of the ERK pathway. Administration of both MEK and HDAC inhibitors represents a promising chemotherapeutic strategy with improved safety for cancer patients.

Acute Effects of Vascular Modifying Agents in Solid Tumors Assessed by Noninvasive Laser Doppler Flowmetry and Near Infrared Spectroscopy

Directory of Open Access Journals (Sweden)

Michael Kragh

2002-01-01

Full Text Available The potential of noninvasive laser Doppler flowmetry (LDF and near infrared spectroscopy (NIRS to detect acute effects of different vascular-modifying agents on perfusion and blood volume in tumors was evaluated. C3H mouse mammary carcinomas (∼200 mm3 in the rear foot of CDF1 mice were treated with flavone acetic acid (FAA, 150 mg/kg, 5,6-dimethylxanthenone-4acetic acid (DMXAA, 20 mg/kg, combretastatin A-4 disodium phosphate (CAMP, 250 mg/kg, hydralazine (HDZ, 5 mg/kg, or nicotinamide (NTA, 500 mg/kg. Tumor perfusion before and after treatment was evaluated by noninvasive LDF, using a 41°C heated custombuilt LDF probe with four integrated laser/receiver units, and tumor blood volume was estimated by MRS, using light guide coupled reflectance measurements at 800±10 nm. FAA, DMXAA, CAMP, and HDZ significantly decreased tumor perfusion by 50%, 47%, 73%, and 78%, respectively. In addition, FAA, DMXAA, and HDZ significantly reduced the blood volume within the tumor, indicating that these compounds to some degree shunted blood from the tumor to adjacent tissue, HDZ being most potent. CAMP caused no change in the tumor blood volume, indicating that the mechanism of action of CAMP was vascular shut down with the blood pool trapped in the tumor. NTA caused no change in either tumor perfusion or tumor blood volume. We conclude that noninvasive LDF and MRS can determine acute effects of vascular modifying agents on tumor perfusion and blood volume.

Tumor dedifferentiation: diagnostic and therapeutic implications

Directory of Open Access Journals (Sweden)

Abhimanyu Jha

2017-09-01

Full Text Available Some of the neoplasm especially malignant tumors are notorious in masquerading their cell of origin because of additional mutations which drives them to differentiate into unusual phenotype. This is implicated to a phenomenon of tumor dedifferentiation which can mislead into inappropriate categorization and therapy. Dedifferentiation is well recognized in sarcomas such as liposarcoma, chondrosarcoma and MPNST. However, it can also develop in carcinomas, melanomas and lymphomas at initial diagnosis, following therapy or at recurrence.  The phenomenon has been reported in both primary tumors as well as at metastatic foci. A correct and early pathological identification of this phenomenon might profoundly help in guiding appropriate therapy. Clinical and radiological findings, immunohistochemistry and genetic analysis are often required for correct lineage identification of these tumors.

Computer-assisted quantitative assessment of power Doppler US: effects of microbubble contrast agent in the differentiation of breast tumors

International Nuclear Information System (INIS)

Kettenbach, Joachim; Helbich, Thomas H.; Huber, Sabine; Zuna, Ivan; Dock, Wolfgang

2005-01-01

Rationale and objectives: To objectively quantify the effects of a microbubble contrast agent to differentiate breast tumors with power doppler ultrasound and to compare these results with color doppler ultrasound (CD US). Methods: In 47 patients a microbubble contrast agent was injected intravenously. Computer-assisted quantitative assessment of the color pixel density was performed to evaluate the increase in Doppler signals. Results were compared to previously published results of a color Doppler ultrasound study. Results: Peak color pixel density at contrast-enhanced power Doppler ultrasound was higher for carcinomas than for benign tumors (P < 0.03). Time to peak enhancement was shorter in carcinomas than in benign tumors (P < 0.01). For both parameters, diagnostic accuracy of power Doppler ultrasound was 69 and 78%, and for color Doppler ultrasound 62 and 76%, respectively. Conclusions: Quantitative assessment of contrast-enhanced power Doppler ultrasound showed significant differences in malignant and benign breast tumors. Diagnostic accuracy of contrast-enhanced power Doppler ultrasound was higher compared to color Doppler ultrasound

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.

Small Scaffolds, Big Potential: Developing Miniature Proteins as Therapeutic Agents.

Science.gov (United States)

Holub, Justin M

2017-09-01

Preclinical Research Miniature proteins are a class of oligopeptide characterized by their short sequence lengths and ability to adopt well-folded, three-dimensional structures. Because of their biomimetic nature and synthetic tractability, miniature proteins have been used to study a range of biochemical processes including fast protein folding, signal transduction, catalysis and molecular transport. Recently, miniature proteins have been gaining traction as potential therapeutic agents because their small size and ability to fold into defined tertiary structures facilitates their development as protein-based drugs. This research overview discusses emerging developments involving the use of miniature proteins as scaffolds to design novel therapeutics for the treatment and study of human disease. Specifically, this review will explore strategies to: (i) stabilize miniature protein tertiary structure; (ii) optimize biomolecular recognition by grafting functional epitopes onto miniature protein scaffolds; and (iii) enhance cytosolic delivery of miniature proteins through the use of cationic motifs that facilitate endosomal escape. These objectives are discussed not only to address challenges in developing effective miniature protein-based drugs, but also to highlight the tremendous potential miniature proteins hold for combating and understanding human disease. Drug Dev Res 78 : 268-282, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

HemoHIM enhances the therapeutic efficacy of ionizing radiation treatment in tumor-bearing mice.

Science.gov (United States)

Park, Hae-Ran; Ju, Eun-Jin; Jo, Sung-Kee; Jung, Uhee; Kim, Sung-Ho

2010-02-01

Although radiotherapy is commonly used for a variety of cancers, radiotherapy alone does not achieve a satisfactory therapeutic outcome. In this study, we examined the possibility that HemoHIM can enhance the anticancer effects of ionizing radiation (IR) in melanoma-bearing mice. The HemoHIM was prepared by adding the ethanol-insoluble fraction to the total water extract of a mixture of three edible herbs-Angelica Radix, Cnidium Rhizoma, and Paeonia Radix. Anticancer effects of HemoHIM were evaluated in melanoma-bearing mice exposed to IR. IR treatment (5 Gy at 7 days after melanoma cell injection) reduced the weight of the solid tumors, and HemoHIM supplementation with IR enhanced the decreases in tumor weight (P HemoHIM administration also increased the activity of natural killer cells and cytotoxic T cells, although the proportions of these cells in spleen were not different. In addition, HemoHIM administration increased the interleukin-2 and tumor necrosis factor-alpha secretion from lymphocytes stimulated with concanavalin A, which seemed to contribute to the enhanced efficacy of HemoHIM in tumor-bearing mice treated with IR. In conclusion, HemoHIM may be a beneficial supplement during radiotherapy for enhancing the antitumor efficacy.

Menahydroquinone-4 Prodrug: A Promising Candidate Anti-Hepatocellular Carcinoma Agent.

Science.gov (United States)

Enjoji, Munechika; Watase, Daisuke; Matsunaga, Kazuhisa; Kusuda, Mariko; Nagata-Akaho, Nami; Karube, Yoshiharu; Takata, Jiro

2015-07-22

Recently, new therapeutics have been developed for hepatocellular carcinoma (HCC). However, the overall survival rate of HCC patients is still unsatisfactory; one of the reasons for this is the high frequency of recurrence after radical treatment. Consequently, to improve prognosis, it will be important to develop a novel anti-tumor agent that is especially effective against HCC recurrence. For clinical application, long-term safety, together with high anti-tumor efficacy, is desirable. Recent studies have proposed menahydroquinone-4 1,4-bis- N,N -dimethylglycinate hydrochloride (MKH-DMG), a prodrug of menahydroquinone-4 (MKH), as a promising candidate for HCC treatment including the inhibition of recurrence; MKH-DMG has been shown to achieve good selective accumulation of MKH in tumor cells, resulting in satisfactory inhibition of cell proliferation in des-γ-carboxyl prothrombin (DCP)-positive and DCP-negative HCC cell lines. In a spleen-liver metastasis mouse model, MKH-DMG has been demonstrated to have anti-proliferation and anti-metastatic effects in vivo . The characteristics of MKH-DMG as a novel anti-HCC agent are presented in this review article.

Functional imaging of larynx via 256-Slice Multi-Detector Computed Tomography in patients with laryngeal tumors: A faster, better and more reliable pre-therapeutic evaluation

International Nuclear Information System (INIS)

Celebi, Irfan; Basak, Muzaffer; Ucgul, Ayhan; Yildirim, Hakan; Oz, Aysel; Vural, Cetin

2012-01-01

Objective: To determine the clinical utility of using dynamic maneuvers during imaging of larynx via 256-Slice Multi-Detector Computed Tomography in the pre-therapeutic evaluation of laryngeal tumors. Materials and methods: A total of 27 patients (7 women, 20 men; aged 53–76 years) diagnosed with laryngeal squamous cell carcinoma were evaluated pre-therapeutically via contrast enhanced axial CT scans during consecutive phases of phonation (PP), inspiration (IP) and Valsalva maneuver (VP). Results: In 2 of 5 patients diagnosed with T1a glottic tumor, scans obtained during VP and PP were normal while the CT scans obtained during IP clearly showed a mass. In all patients (27/27) PP provided visualization of the ventricle, on coronal plane images and the pyriform sinus apices, on axial plane images. Involvement of the anterior commissure was best assessable on axial plane IP images (sensitivity 93%, specificity 92%). In cases of stage T1–T3 tumors use of dynamic maneuvers during laryngeal CT imaging showed the location and extension of the tumor better than the single phase CT scans did. We did not find a significant improvement in the pre-therapeutic evaluation in stage T4 tumors. Conclusion: Providing markedly clearer and more detailed evaluation of mucosal surfaces and deep structures of the larynx and mobility of the cords than do conventional scans, use of dynamic laryngeal maneuvers during laryngeal CT imaging seems to be an useful alternative in the pre-therapeutic assessment of laryngeal tumors.

Dendrimer-based Macromolecular MRI Contrast Agents: Characteristics and Application

Directory of Open Access Journals (Sweden)

Hisataka Kobayashi

2003-01-01

Full Text Available Numerous macromolecular MRI contrast agents prepared employing relatively simple chemistry may be readily available that can provide sufficient enhancement for multiple applications. These agents operate using a ~100-fold lower concentration of gadolinium ions in comparison to the necessary concentration of iodine employed in CT imaging. Herein, we describe some of the general potential directions of macromolecular MRI contrast agents using our recently reported families of dendrimer-based agents as examples. Changes in molecular size altered the route of excretion. Smaller-sized contrast agents less than 60 kDa molecular weight were excreted through the kidney resulting in these agents being potentially suitable as functional renal contrast agents. Hydrophilic and larger-sized contrast agents were found better suited for use as blood pool contrast agents. Hydrophobic variants formed with polypropylenimine diaminobutane dendrimer cores created liver contrast agents. Larger hydrophilic agents are useful for lymphatic imaging. Finally, contrast agents conjugated with either monoclonal antibodies or with avidin are able to function as tumor-specific contrast agents, which also might be employed as therapeutic drugs for either gadolinium neutron capture therapy or in conjunction with radioimmunotherapy.

Combination of systemic chemotherapy with local stem cell delivered S-TRAIL in resected brain tumors.

Science.gov (United States)

Redjal, Navid; Zhu, Yanni; Shah, Khalid

2015-01-01

Despite advances in standard therapies, the survival of glioblastoma multiforme (GBM) patients has not improved. Limitations to successful translation of new therapies include poor delivery of systemic therapies and use of simplified preclinical models which fail to reflect the clinical complexity of GBMs. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis specifically in tumor cells and we have tested its efficacy by on-site delivery via engineered stem cells (SC) in mouse models of GBM that mimic the clinical scenario of tumor aggressiveness and resection. However, about half of tumor lines are resistant to TRAIL and overcoming TRAIL-resistance in GBM by combining therapeutic agents that are currently in clinical trials with SC-TRAIL and understanding the molecular dynamics of these combination therapies are critical to the broad use of TRAIL as a therapeutic agent in clinics. In this study, we screened clinically relevant chemotherapeutic agents for their ability to sensitize resistant GBM cell lines to TRAIL induced apoptosis. We show that low dose cisplatin increases surface receptor expression of death receptor 4/5 post G2 cycle arrest and sensitizes GBM cells to TRAIL induced apoptosis. In vivo, using an intracranial resection model of resistant primary human-derived GBM and real-time optical imaging, we show that a low dose of cisplatin in combination with synthetic extracellular matrix encapsulated SC-TRAIL significantly decreases tumor regrowth and increases survival in mice bearing GBM. This study has the potential to help expedite effective translation of local stem cell-based delivery of TRAIL into the clinical setting to target a broad spectrum of GBMs. © 2014 AlphaMed Press.

MicroRNA Signatures as Biomarkers and Therapeutic Target for CNS Embryonal Tumors: The Pros and the Cons

Directory of Open Access Journals (Sweden)

Tarek Shalaby

2014-11-01

Full Text Available Embryonal tumors of the central nervous system represent a heterogeneous group of childhood cancers with an unknown pathogenesis; diagnosis, on the basis of histological appearance alone, is controversial and patients’ response to therapy is difficult to predict. They encompass medulloblastoma, atypical teratoid/rhabdoid tumors and a group of primitive neuroectodermal tumors. All are aggressive tumors with the tendency to disseminate throughout the central nervous system. The large amount of genomic and molecular data generated over the last 5–10 years encourages optimism that new molecular targets will soon improve outcomes. Recent neurobiological studies have uncovered the key role of microRNAs (miRNAs in embryonal tumors biology and their potential use as biomarkers is increasingly being recognized and investigated. However the successful use of microRNAs as reliable biomarkers for the detection and management of pediatric brain tumors represents a substantial challenge. This review debates the importance of miRNAs in the biology of central nervous systemembryonal tumors focusing on medulloblastoma and atypical teratoid/rhabdoid tumors and highlights the advantages as well as the limitations of their prospective application as biomarkers and candidates for molecular therapeutic targets.

Perspective on Cancer Therapeutics Utilizing Analysis of Circulating Tumor Cells

Directory of Open Access Journals (Sweden)

Keun-Yeong Jeong

2018-04-01

Full Text Available Various methods are available for cancer screening, and the methods are performed depending on the origin site of cancer. Among these methods, biopsy followed by medical imaging is the most common. After cancer progression is determined, an optimal treatment—such as surgery, chemotherapy, and/or radiation therapy—is selected. A new assay has been developed that detects circulating tumor cells (CTCs. Tracking changes in CTCs may reveal important tumoral sensitivity information or resistance patterns to specific regimens and prompt changes in therapy on a personalized basis. Characterization of CTCs at the DNA, RNA, and protein levels is important for gaining insight for clinical applications. A small number of CTCs can be analyzed to obtain genome information such as the progression of cancer including metastasis, even in a single cluster. Although many clinical studies, particularly CTC enumeration and detection of specific oncogene expression, have increased the success rate of diagnosis and predicting prognosis, there is no consensus regarding the technical approaches and various aspects of the methodology, making it difficult to standardize optimal methods for CTC analysis. However, ongoing technological advances are currently being achieved and large-scale clinical studies are being conducted. Applying CTC analysis in the clinic would be very useful for advancing diagnosis, prognosis prediction, and therapeutics.

Primary evaluation of a nickel-chlorophyll derivative as a multimodality agent for tumor imaging and photodynamic therapy

International Nuclear Information System (INIS)

Ozge Er; Fatma Yurt Lambrecht; Kasim Ocakoglu; Cagla Kayabasi; Cumhur Gunduz

2015-01-01

In this study, the biological potential of a nickel chlorophyll derivative (Ni-PH-A) as a multimodal agent for tumor imaging and photodynamic therapy (PDT) was investigated. Optimum conditions of labeling with 131 I were investigated and determined as pH 10 and 1 mg amount of iodogen. Biodistribution results of 131 I labeled Ni-PH-A in female rats indicated that radiolabeled Ni-PH-A maximum uptake in the liver, spleen and ovary was observed at 30 min. Intercellular uptake and PDT efficacy of Ni-PH-A were better in MDAH-2774 (human ovarian endometrioid adenocarcinoma) than in MCF-7 (human breast adenocarcinoma) cells. Ni-PH-A might be a promising multimodal agent for lung, ovary and liver tumor imaging and PDT. (author)

The analytical of radiochemical purity of tumor receptor imaging agent 99Tcm-octreotide

International Nuclear Information System (INIS)

Wang Xufu; Zuo Shuyao; Shao Wenbo; Wang Guoming; Sun Jianwen; Zhang Qin

2003-01-01

The radiochemical purity of tumor receptor imaging agent 99 Tc m -octreotide is measured by High Pressure Liquid Chromatography (HPLC) and two systems of chromatography combining method of silver stain. The results show that the radiochemical purity of 98 Tc m -octreotide measured by both methods are effective and correct. It can separate 99 Tc m -octreotide from other radioactive compositions correctly and effectively

Bromine-77-labeled estrogen receptor-binding radiopharmaceuticals for breast tumor imaging

International Nuclear Information System (INIS)

McElvany, K.D.

1985-01-01

Two derivatives of 16α-bromoestradiol, both with and without an 11β-methoxy substituent, have been labeled with bromine-77 and evaluated as potential breast tumor imaging agents. Extensive characterization of these radiotracers in animal models has demonstrated their effective concentration in estrogen target tissues. Preliminary clinical studies have demonstrated the potential of radiolabeled estrogens for breast tumor imaging; however, the suboptimal decay properties of bromine-77 limit the utility of these agents in imaging studies. These results with 77 -Br-labeled estrogens suggest that estrogen derivatives labeled with other radionuclides should provide enhanced image resolution with various imaging devices. Although the decay characteristics of bromine-77 are such that it is not ideally suited to imaging with conventional gamma cameras, it may be a useful radionuclide for therapeutic applications

77 FR 62521 - Prospective Grant of Exclusive License: The Development of Therapeutic Agents for the Treatment...

Science.gov (United States)

2012-10-15

... interleukin-10 (IL-10) inhibitor as a dual-biologic therapy to treat metastatic breast cancer, or ii) incorporating a p53 isoform antisense oligonucleotide as a single biologic therapy to treat T- cell lymphoma... Exclusive License: The Development of Therapeutic Agents for the Treatment of Metastatic Breast Cancer and T...

Nitric oxide-releasing agents enhance cytokine-induced tumor necrosis factor synthesis in human mononuclear cells

NARCIS (Netherlands)

Eigler, A; Sinha, B; Endres, S

1993-01-01

In septic shock tumor necrosis factor (TNF) leads to increased nitric oxide (NO) production by induction of NO synthase. An inverse regulatory effect, the influence of NO on cytokine synthesis, has rarely been investigated. The present study assessed the influence of NO-releasing agents on TNF

Agentes antineoplásicos biorredutíveis: uma nova alternativa para o tratamento de tumores sólidos

Directory of Open Access Journals (Sweden)

Oliveira Renata Barbosa de

2002-01-01

Full Text Available A problem often encountered in cancer therapy is the presence of tumor cell subpopulation that are resistant to treatment. Solid tumors frequently contain hypoxic cells that are resistant to killing by ionizing radiation and also by many chemotherapeutic agents. However, these hypoxic cells can be exploited for therapy by non-toxic hypoxic-activated prodrugs. Bioreductive drugs require metabolic reduction to generate cytotoxic metabolites. This process is facilitated by appropriate reductases and the lower oxygen conditions present in solid tumors. The unique presence of hypoxic cells in human tumors provides an important target for selective cancer therapy.

Engineered Polymer-Based Nanomaterials for Diagnostic, Therapeutic and Theranostic Applications.

Science.gov (United States)

Parisi, Ortensia Ilaria; Scrivano, Luca; Sinicropi, Maria Stefania; Picci, Nevio; Puoci, Francesco

2016-01-01

Nanomedicine can be defined as the medical application of molecular nanotechnology and it plays a key role and pharmaceutical research and development, especially related to cancer prevention, monitoring, diagnosis and treatment. In this context, nanomaterials are attracting significant research interest due to their abilities to stay in the blood for long time, accumulate in pathological sites including tumors or inflammatory areas via the enhanced permeability and retention (EPR) effect, and facilitate targeted delivery of specific therapeutic agents. In the last decades, considerable attention was attracted by the development of nano-sized carriers, based on natural or synthetic polymers, able to provide the controlled release of anticancer drugs in the aim to overcome the drawbacks associated to the conventional chemotherapy. Furthermore, when loaded with imaging agents, this kind of systems offers the opportunity to exploit optical or magnetic resonance imaging (MRI) in cancer diagnosis. Polymeric materials are characterized by several functionalities where both therapeutic and imaging components, and also targeting moieties, can be attached for simultaneous targeted therapy and imaging providing innovative platforms defined as theranostic agents with a great potential in monitoring and treatment of cancer.

Pancreatic Adenocarcinoma Therapeutic Targets Revealed by Tumor-Stroma Cross-Talk Analyses in Patient-Derived Xenografts

Directory of Open Access Journals (Sweden)

Rémy Nicolle

2017-11-01

Full Text Available Preclinical models based on patient-derived xenografts have remarkable specificity in distinguishing transformed human tumor cells from non-transformed murine stromal cells computationally. We obtained 29 pancreatic ductal adenocarcinoma (PDAC xenografts from either resectable or non-resectable patients (surgery and endoscopic ultrasound-guided fine-needle aspirate, respectively. Extensive multiomic profiling revealed two subtypes with distinct clinical outcomes. These subtypes uncovered specific alterations in DNA methylation and transcription as well as in signaling pathways involved in tumor-stromal cross-talk. The analysis of these pathways indicates therapeutic opportunities for targeting both compartments and their interactions. In particular, we show that inhibiting NPC1L1 with Ezetimibe, a clinically available drug, might be an efficient approach for treating pancreatic cancers. These findings uncover the complex and diverse interplay between PDAC tumors and the stroma and demonstrate the pivotal role of xenografts for drug discovery and relevance to PDAC.

Quantitative Evaluation of Tumor Early Response to a Vascular-Disrupting Agent with Dynamic PET.

Science.gov (United States)

Guo, Ning; Zhang, Fan; Zhang, Xiaomeng; Guo, Jinxia; Lang, Lixin; Kiesewetter, Dale O; Niu, Gang; Li, Quanzheng; Chen, Xiaoyuan

2015-12-01

The purpose of this study is to evaluate the early response of tumors to a vascular-disrupting agent (VDA) VEGF121/recombinant toxin gelonin (rGel) using dynamic [(18)F]FPPRGD2 positron emission tomography (PET) and kinetic parameter estimation. Two tumor xenograft models: U87MG (highly vascularized) and A549 (moderately vascularized), were selected, and both were randomized into treatment and control groups. Sixty-minute dynamic PET scans with [(18)F]FPPRGD2 that targets to integrin αvβ3 were performed at days 0 (baseline), 1, and 3 since VEGF121/rGel treatment started. Dynamic PET-derived binding potential (BPND) and parametric maps were compared with tumor uptake (%ID/g) and the static PET image at 1 h after the tracer administration. The growth of U87MG tumor was obviously delayed upon VEGF121/rGel treatment. A549 tumor was not responsive to the same treatment. BPND of treated U87MG tumors decreased significantly at day 1 (p dynamic PET with [(18)F]FPPRGD2 shows advantages in distinguishing effective from ineffective treatment during the course of VEGF121/rGel therapy at early stage and is therefore more sensitive in assessing therapy response than static PET.

Antiangiogenic agents in the treatment of recurrent or newly diagnosed glioblastoma: Analysis of single-agent and combined modality approaches

International Nuclear Information System (INIS)

Beal, Kathryn; Abrey, Lauren E; Gutin, Philip H

2011-01-01

Surgical resection followed by radiotherapy and temozolomide in newly diagnosed glioblastoma can prolong survival, but it is not curative. For patients with disease progression after frontline therapy, there is no standard of care, although further surgery, chemotherapy, and radiotherapy may be used. Antiangiogenic therapies may be appropriate for treating glioblastomas because angiogenesis is critical to tumor growth. In a large, noncomparative phase II trial, bevacizumab was evaluated alone and with irinotecan in patients with recurrent glioblastoma; combination treatment was associated with an estimated 6-month progression-free survival (PFS) rate of 50.3%, a median overall survival of 8.9 months, and a response rate of 37.8%. Single-agent bevacizumab also exceeded the predetermined threshold of activity for salvage chemotherapy (6-month PFS rate, 15%), achieving a 6-month PFS rate of 42.6% (p < 0.0001). On the basis of these results and those from another phase II trial, the US Food and Drug Administration granted accelerated approval of single-agent bevacizumab for the treatment of glioblastoma that has progressed following prior therapy. Potential antiangiogenic agents-such as cilengitide and XL184-also show evidence of single-agent activity in recurrent glioblastoma. Moreover, the use of antiangiogenic agents with radiation at disease progression may improve the therapeutic ratio of single-modality approaches. Overall, these agents appear to be well tolerated, with adverse event profiles similar to those reported in studies of other solid tumors. Further research is needed to determine the role of antiangiogenic therapy in frontline treatment and to identify the optimal schedule and partnering agents for use in combination therapy

Polyethylenimine-based siRNA nanocomplexes reprogram tumor-associated dendritic cells via TLR5 to elicit therapeutic antitumor immunity.

Science.gov (United States)

Cubillos-Ruiz, Juan R; Engle, Xavier; Scarlett, Uciane K; Martinez, Diana; Barber, Amorette; Elgueta, Raul; Wang, Li; Nesbeth, Yolanda; Durant, Yvon; Gewirtz, Andrew T; Sentman, Charles L; Kedl, Ross; Conejo-Garcia, Jose R

2009-08-01

The success of clinically relevant immunotherapies requires reversing tumor-induced immunosuppression. Here we demonstrated that linear polyethylenimine-based (PEI-based) nanoparticles encapsulating siRNA were preferentially and avidly engulfed by regulatory DCs expressing CD11c and programmed cell death 1-ligand 1 (PD-L1) at ovarian cancer locations in mice. PEI-siRNA uptake transformed these DCs from immunosuppressive cells to efficient antigen-presenting cells that activated tumor-reactive lymphocytes and exerted direct tumoricidal activity, both in vivo and in situ. PEI triggered robust and selective TLR5 activation in vitro and elicited the production of hallmark TLR5-inducible cytokines in WT mice, but not in Tlr5-/- littermates. Thus, PEI is a TLR5 agonist that, to our knowledge, was not previously recognized. In addition, PEI-complexed nontargeting siRNA oligonucleotides stimulated TLR3 and TLR7. The nonspecific activation of multiple TLRs (specifically, TLR5 and TLR7) reversed the tolerogenic phenotype of human and mouse ovarian tumor-associated DCs. In ovarian carcinoma-bearing mice, this induced T cell-mediated tumor regression and prolonged survival in a manner dependent upon myeloid differentiation primary response gene 88 (MyD88; i.e., independent of TLR3). Furthermore, gene-specific siRNA-PEI nanocomplexes that silenced immunosuppressive molecules on mouse tumor-associated DCs elicited discernibly superior antitumor immunity and enhanced therapeutic effects compared with nontargeting siRNA-PEI nanocomplexes. Our results demonstrate that the intrinsic TLR5 and TLR7 stimulation of siRNA-PEI nanoparticles synergizes with the gene-specific silencing activity of siRNA to transform tumor-infiltrating regulatory DCs into DCs capable of promoting therapeutic antitumor immunity.

Cyanine 5.5 conjugated nanobubbles as a tumor selective contrast agent for dual ultrasound-fluorescence imaging in a mouse model.

Directory of Open Access Journals (Sweden)

Liyi Mai

Full Text Available Nanobubbles and microbubbles are non-invasive ultrasound imaging contrast agents that may potentially enhance diagnosis of tumors. However, to date, both nanobubbles and microbubbles display poor in vivo tumor-selectivity over non-targeted organs such as liver. We report here cyanine 5.5 conjugated nanobubbles (cy5.5-nanobubbles of a biocompatible chitosan-vitamin C lipid system as a dual ultrasound-fluorescence contrast agent that achieved tumor-selective imaging in a mouse tumor model. Cy5.5-nanobubble suspension contained single bubble spheres and clusters of bubble spheres with the size ranging between 400-800 nm. In the in vivo mouse study, enhancement of ultrasound signals at tumor site was found to persist over 2 h while tumor-selective fluorescence emission was persistently observed over 24 h with intravenous injection of cy5.5-nanobubbles. In vitro cell study indicated that cy5.5-flurescence dye was able to accumulate in cancer cells due to the unique conjugated nanobubble structure. Further in vivo fluorescence study suggested that cy5.5-nanobubbles were mainly located at tumor site and in the bladder of mice. Subsequent analysis confirmed that accumulation of high fluorescence was present at the intact subcutaneous tumor site and in isolated tumor tissue but not in liver tissue post intravenous injection of cy5.5-nanobubbles. All these results led to the conclusion that cy5.5-nanobubbles with unique crosslinked chitosan-vitamin C lipid system have achieved tumor-selective imaging in vivo.

Angiogenesis and Its Therapeutic Opportunities

Directory of Open Access Journals (Sweden)

So Young Yoo

2013-01-01

Full Text Available Angiogenesis plays critical roles in human physiology that range from reproduction and fetal growth to wound healing and tissue repair. The sophisticated multistep process is tightly regulated in a spatial and temporal manner by “on-off switch signals” between angiogenic factors, extracellular matrix components, and endothelial cells. Uncontrolled angiogenesis may lead to several angiogenic disorders, including vascular insufficiency (myocardial or critical limb ischemia and vascular overgrowth (hemangiomas, vascularized tumors, and retinopathies. Thus, numerous therapeutic opportunities can be envisaged through the successful understanding and subsequent manipulation of angiogenesis. Here, we review the clinical implications of angiogenesis and discuss pro- and antiangiogenic agents that offer potential therapy for cancer and other angiogenic diseases.

A Specific Inhibitor of TGF-β Receptor Kinase, SB-431542, as a Potent Antitumor Agent for Human Cancers

Directory of Open Access Journals (Sweden)

Sunil K. Halder

2005-05-01

Full Text Available Small molecule inhibitors of signaling pathways have proven to be extremely useful for the development of therapeutic strategies for human cancers. Blocking the tumor-promoting effects of transforming growth factor-β (TGF-β in advanced stage carcinogenesis provides a potentially interesting drug target for therapeutic intervention. Although very few TGF-β receptor kinase inhibitors (TRKI are now emerging in preclinical studies, nothing is known about how these inhibitors might regulate the tumor-suppressive or tumor-promoting effects of TGF-β, or when these inhibitors might be useful for treatment during cancer progression. We have investigated the potential of TRKI in new therapeutic approaches in preclinical models. Here, we demonstrate that the TRKI, SB-431542, inhibits TGF-β-induced transcription, gene expression, apoptosis, and growth suppression. We have observed that SB-431542 attenuates the tumor-promoting effects of TGF-β, including TGF-β-induced EMT, cell motility, migration and invasion, and vascular endothelial growth factor secretion in human cancer cell lines. Interestingly, SB-431542 induces anchorage independent growth of cells that are growth-inhibited by TGF-β, whereas it reduces colony formation by cells that are growth-promoted by TGF-β. However, SB-431542 has no effect on a cell line that failed to respond to TGF-β. This represents a novel potential application of these inhibitors as therapeutic agents for human cancers with the goal of blocking tumor invasion, angiogenesis, and metastasis, when tumors are refractory to TGF-β-induced tumor-suppressor functions but responsive to tumor-promoting effects of TGF-β.

The distribution of the therapeutic monoclonal antibodies cetuximab and trastuzumab within solid tumors

International Nuclear Information System (INIS)

Lee, Carol M; Tannock, Ian F

2010-01-01

Poor distribution of some anticancer drugs in solid tumors may limit their anti-tumor activity. Here we used immunohistochemistry to quantify the distribution of the therapeutic monoclonal antibodies cetuximab and trastuzumab in relation to blood vessels and to regions of hypoxia in human tumor xenografts. The antibodies were injected into mice implanted with human epidermoid carcinoma A431 or human breast carcinoma MDA-MB-231 transfected with ERBB2 (231-H2N) that express high levels of ErbB1 and ErbB2 respectively, or wild-type MDA-MB-231, which expresses intermediate levels of ErbB1 and low levels of ErbB2. The distribution of cetuximab in A431 xenografts and trastuzumab in 231-H2N xenografts was time and dose dependent. At early intervals after injection of 1 mg cetuximab into A431 xenografts, the concentration of cetuximab decreased with increasing distance from blood vessels, but became more uniformly distributed at later times; there remained however limited distribution and binding in hypoxic regions of tumors. Injection of lower doses of cetuximab led to heterogeneous distributions. Similar results were observed with trastuzumab in 231-H2N xenografts. In MDA-MB-231 xenografts, which express lower levels of ErbB1, homogeneity of distribution of cetuximab was achieved more rapidly. Cetuximab and trastuzumab distribute slowly, but at higher doses achieve a relatively uniform distribution after about 24 hours, most likely due to their long half-lives in the circulation. There remains poor distribution within hypoxic regions of tumors

Radiation treatment of brain tumors: Concepts and strategies

International Nuclear Information System (INIS)

Marks, J.E.

1989-01-01

Ionizing radiation has demonstrated clinical value for a multitude of CNS tumors. Application of the different physical modalities available has made it possible for the radiotherapist to concentrate the radiation in the region of the tumor with relative sparing of the surrounding normal tissues. Correlation of radiation dose with effect on cranial soft tissues, normal brain, and tumor has shown increasing effect with increasing dose. By using different physical modalities to alter the distribution of radiation dose, it is possible to increase the dose to the tumor and reduce the dose to the normal tissues. Alteration of the volume irradiated and the dose delivered to cranial soft tissues, normal brain, and tumor are strategies that have been effective in improving survival and decreasing complications. The quest for therapeutic gain using hyperbaric oxygen, neutrons, radiation sensitizers, chemotherapeutic agents, and BNCT has met with limited success. Both neoplastic and normal cells are affected simultaneously by all modalities of treatment, including ionizing radiation. Consequently, one is unable to totally depopulate a tumor without irreversibly damaging the normal tissues. In the case of radiation, it is the brain that limits delivery of curative doses, and in the case of chemical additives, it is other organ systems, such as bone marrow, liver, lung, kidneys, and peripheral nerves. Thus, the major obstacle in the treatment of malignant gliomas is our inability to preferentially affect the tumor with the modalities available. Until it is possible to directly target the neoplastic cell without affecting so many of the adjacent normal cells, the quest for therapeutic gain will go unrealized.72 references

Potent antitumor bifunctional DNA alkylating agents, synthesis and biological activities of 3a-aza-cyclopenta[a]indenes.

Science.gov (United States)

Kakadiya, Rajesh; Dong, Huajin; Lee, Pei-Chih; Kapuriya, Naval; Zhang, Xiuguo; Chou, Ting-Chao; Lee, Te-Chang; Kapuriya, Kalpana; Shah, Anamik; Su, Tsann-Long

2009-08-01

A series of bifunctional DNA interstrand cross-linking agents, bis(hydroxymethyl)- and bis(carbamates)-8H-3a-azacyclopenta[a]indene-1-yl derivatives were synthesized for antitumor evaluation. The preliminary antitumor studies revealed that these agents exhibited potent cytotoxicity in vitro and antitumor therapeutic efficacy against human tumor xenografts in vivo. Furthermore, these derivatives have little or no cross-resistance to either Taxol or Vinblastine. Remarkably, complete tumor remission in nude mice bearing human breast carcinoma MX-1 xenograft by 13a,b and 14g,h and significant suppression against prostate adenocarcinoma PC3 xenograft by 13b were achieved at the maximum tolerable dose with relatively low toxicity. In addition, these agents induce DNA interstrand cross-linking and substantial G2/M phase arrest in human non-small lung carcinoma H1299 cells. The current studies suggested that these agents are promising candidates for preclinical studies.

Systemic Administration of Interleukin 2 Enhances the Therapeutic Efficacy of Dendritic Cell-Based Tumor Vaccines

Science.gov (United States)

Shimizu, K.; Fields, R. C.; Giedlin, M.; Mule, J. J.

1999-03-01

We have reported previously that murine bone marrow-derived dendritic cells (DC) pulsed with whole tumor lysates can mediate potent antitumor immune responses both in vitro and in vivo. Because successful therapy was dependent on host immune T cells, we have now evaluated whether the systemic administration of the T cell stimulatory/growth promoting cytokine interleukin-2 (IL-2) could enhance tumor lysate-pulsed DC-based immunizations to further promote protective immunity toward, and therapeutic rejection of, syngeneic murine tumors. In three separate approaches using a weakly immunogenic sarcoma (MCA-207), the systemic administration of non-toxic doses of recombinant IL-2 (20,000 and 40,000 IU/dose) was capable of mediating significant increases in the potency of DC-based immunizations. IL-2 could augment the efficacy of tumor lysate-pulsed DC to induce protective immunity to lethal tumor challenge as well as enhance splenic cytotoxic T lymphocyte activity and interferon-γ production in these treated mice. Moreover, treatment with the combination of tumor lysate-pulsed DC and IL-2 could also mediate regressions of established pulmonary 3-day micrometastases and 7-day macrometastases as well as established 14- and 28-day s.c. tumors, leading to either significant cure rates or prolongation in overall survival. Collectively, these findings show that nontoxic doses of recombinant IL-2 can potentiate the antitumor effects of tumor lysate-pulsed DC in vivo and provide preclinical rationale for the use of IL-2 in DC-based vaccine strategies in patients with advanced cancer.

The Clinical Importance of Assessing Tumor Hypoxia: Relationship of Tumor Hypoxia to Prognosis and Therapeutic Opportunities

Science.gov (United States)

Walsh, Joseph C.; Lebedev, Artem; Aten, Edward; Madsen, Kathleen; Marciano, Liane

2014-01-01

I. Introduction II. The Clinical Importance of Tumor Hypoxia A. Pathophysiology of hypoxia B. Hypoxia's negative impact on the effectiveness of curative treatment 1. Hypoxic tumors accumulate and propagate cancer stem cells 2. Hypoxia reduces the effectiveness of radiotherapy 3. Hypoxia increases metastasis risk and reduces the effectiveness of surgery 4. Hypoxic tumors are resistant to the effects of chemotherapy and chemoradiation C. Hypoxia is prognostic for poor patient outcomes III. Diagnosis of Tumor Hypoxia A. Direct methods 1. Oxygen electrode—direct pO2 measurement most used in cancer research 2. Phosphorescence quenching—alternative direct pO2 measurement 3. Electron paramagnetic resonance 4. 19F-magnetic resonance spectroscopy 5. Overhauser-enhanced MRI B. Endogenous markers of hypoxia 1. Hypoxia-inducible factor-1α 2. Carbonic anhydrase IX 3. Glucose transporter 1 4. Osteopontin 5. A combined IHC panel of protein markers for hypoxia 6. Comet assay C. Physiologic methods 1. Near-infrared spectroscopy/tomography—widely used for pulse oximetry 2. Photoacoustic tomography 3. Contrast-enhanced color duplex sonography 4. MRI-based measurements 5. Blood oxygen level-dependent MRI 6. Pimonidazole 7. EF5 (pentafluorinated etanidazole) 8. Hypoxia PET imaging—physiologic hypoxia measurement providing tomographic information a. 18F-fluoromisonidazole b. 18F-fluoroazomycinarabinofuranoside c. 18F-EF5 (pentafluorinated etanidazole) d. 18F-flortanidazole e. Copper (II) (diacetyl-bis (N4-methylthiosemicarbazone)) f. 18F-FDG imaging of hypoxia IV. Modifying Hypoxia to Improve Therapeutic Outcomes A. Use of hypoxia information in radiation therapy planning B. Use of hypoxia assessment for selection of patients responsive to nimorazole C. Use of hypoxia assessment for selection of patients responsive to tirapazamine D. Use of hypoxia assessment for selection of patients

Radiotherapy-induced anti-tumor immunity contributes to the therapeutic efficacy of irradiation and can be augmented by CTLA-4 blockade in a mouse model.

Directory of Open Access Journals (Sweden)

Yuya Yoshimoto

Full Text Available PURPOSE: There is growing evidence that tumor-specific immune responses play an important role in anti-cancer therapy, including radiotherapy. Using mouse tumor models we demonstrate that irradiation-induced anti-tumor immunity is essential for the therapeutic efficacy of irradiation and can be augmented by modulation of cytotoxic T lymphocyte (CTL activity. METHODS AND MATERIALS: C57BL/6 mice, syngeneic EL4 lymphoma cells, and Lewis lung carcinoma (LL/C cells were used. Cells were injected into the right femurs of mice. Ten days after inoculation, tumors were treated with 30 Gy of local X-ray irradiation and their growth was subsequently measured. The effect of irradiation on tumor growth delay (TGD was defined as the time (in days for tumors to grow to 500 mm3 in the treated group minus that of the untreated group. Cytokine production and serum antibodies were measured by ELISA and flow cytometry. RESULTS: In the EL4 tumor model, tumors were locally controlled by X-ray irradiation and re-introduced EL4 cells were completely rejected. Mouse EL4-specific systemic immunity was confirmed by splenocyte cytokine production and detection of tumor-specific IgG1 antibodies. In the LL/C tumor model, X-ray irradiation also significantly delayed tumor growth (TGD: 15.4 days and prolonged median survival time (MST to 59 days (versus 28 days in the non-irradiated group. CD8(+ cell depletion using an anti-CD8 antibody significantly decreased the therapeutic efficacy of irradiation (TGD, 8.7 days; MST, 49 days. Next, we examined whether T cell modulation affected the efficacy of radiotherapy. An anti-CTLA-4 antibody significantly increased the anti-tumor activity of radiotherapy (TGD was prolonged from 13.1 to 19.5 days, while anti-FR4 and anti-GITR antibodies did not affect efficacy. CONCLUSIONS: Our results indicate that tumor-specific immune responses play an important role in the therapeutic efficacy of irradiation. Immunomodulation, including CTLA-4

Radiotherapy-Induced Anti-Tumor Immunity Contributes to the Therapeutic Efficacy of Irradiation and Can Be Augmented by CTLA-4 Blockade in a Mouse Model

Science.gov (United States)

Yoshimoto, Yuya; Suzuki, Yoshiyuki; Mimura, Kousaku; Ando, Ken; Oike, Takahiro; Sato, Hiro; Okonogi, Noriyuki; Maruyama, Takanori; Izawa, Shinichiro; Noda, Shin-ei; Fujii, Hideki; Kono, Koji; Nakano, Takashi

2014-01-01

Purpose There is growing evidence that tumor-specific immune responses play an important role in anti-cancer therapy, including radiotherapy. Using mouse tumor models we demonstrate that irradiation-induced anti-tumor immunity is essential for the therapeutic efficacy of irradiation and can be augmented by modulation of cytotoxic T lymphocyte (CTL) activity. Methods and Materials C57BL/6 mice, syngeneic EL4 lymphoma cells, and Lewis lung carcinoma (LL/C) cells were used. Cells were injected into the right femurs of mice. Ten days after inoculation, tumors were treated with 30 Gy of local X-ray irradiation and their growth was subsequently measured. The effect of irradiation on tumor growth delay (TGD) was defined as the time (in days) for tumors to grow to 500 mm3 in the treated group minus that of the untreated group. Cytokine production and serum antibodies were measured by ELISA and flow cytometry. Results In the EL4 tumor model, tumors were locally controlled by X-ray irradiation and re-introduced EL4 cells were completely rejected. Mouse EL4-specific systemic immunity was confirmed by splenocyte cytokine production and detection of tumor-specific IgG1 antibodies. In the LL/C tumor model, X-ray irradiation also significantly delayed tumor growth (TGD: 15.4 days) and prolonged median survival time (MST) to 59 days (versus 28 days in the non-irradiated group). CD8(+) cell depletion using an anti-CD8 antibody significantly decreased the therapeutic efficacy of irradiation (TGD, 8.7 days; MST, 49 days). Next, we examined whether T cell modulation affected the efficacy of radiotherapy. An anti-CTLA-4 antibody significantly increased the anti-tumor activity of radiotherapy (TGD was prolonged from 13.1 to 19.5 days), while anti-FR4 and anti-GITR antibodies did not affect efficacy. Conclusions Our results indicate that tumor-specific immune responses play an important role in the therapeutic efficacy of irradiation. Immunomodulation, including CTLA-4 blockade, may be a

Ultrasound enhanced delivery of molecular imaging and therapeutic agents in Alzheimer's disease mouse models.

Directory of Open Access Journals (Sweden)

Scott B Raymond

Full Text Available Alzheimer's disease is a neurodegenerative disorder typified by the accumulation of a small protein, beta-amyloid, which aggregates and is the primary component of amyloid plaques. Many new therapeutic and diagnostic agents for reducing amyloid plaques have limited efficacy in vivo because of poor transport across the blood-brain barrier. Here we demonstrate that low-intensity focused ultrasound with a microbubble contrast agent may be used to transiently disrupt the blood-brain barrier, allowing non-invasive, localized delivery of imaging fluorophores and immunotherapeutics directly to amyloid plaques. We administered intravenous Trypan blue, an amyloid staining red fluorophore, and anti-amyloid antibodies, concurrently with focused ultrasound therapy in plaque-bearing, transgenic mouse models of Alzheimer's disease with amyloid pathology. MRI guidance permitted selective treatment and monitoring of plaque-heavy anatomical regions, such as the hippocampus. Treated brain regions exhibited 16.5+/-5.4-fold increase in Trypan blue fluorescence and 2.7+/-1.2-fold increase in anti-amyloid antibodies that localized to amyloid plaques. Ultrasound-enhanced delivery was consistently reproduced in two different transgenic strains (APPswe:PSEN1dE9, PDAPP, across a large age range (9-26 months, with and without MR guidance, and with little or no tissue damage. Ultrasound-mediated, transient blood-brain barrier disruption allows the delivery of both therapeutic and molecular imaging agents in Alzheimer's mouse models, which should aid pre-clinical drug screening and imaging probe development. Furthermore, this technique may be used to deliver a wide variety of small and large molecules to the brain for imaging and therapy in other neurodegenerative diseases.

Novel histone deacetylase inhibitors in clinical trials as anti-cancer agents

Directory of Open Access Journals (Sweden)

Petrillo Richard L

2010-02-01

Full Text Available Abstract Histone deacetylases (HDACs can regulate expression of tumor suppressor genes and activities of transcriptional factors involved in both cancer initiation and progression through alteration of either DNA or the structural components of chromatin. Recently, the role of gene repression through modulation such as acetylation in cancer patients has been clinically validated with several inhibitors of HDACs. One of the HDAC inhibitors, vorinostat, has been approved by FDA for treating cutaneous T-cell lymphoma (CTCL for patients with progressive, persistent, or recurrent disease on or following two systemic therapies. Other inhibitors, for example, FK228, PXD101, PCI-24781, ITF2357, MGCD0103, MS-275, valproic acid and LBH589 have also demonstrated therapeutic potential as monotherapy or combination with other anti-tumor drugs in CTCL and other malignancies. At least 80 clinical trials are underway, testing more than eleven different HDAC inhibitory agents including both hematological and solid malignancies. This review focuses on recent development in clinical trials testing HDAC inhibitors as anti-tumor agents.

Targeted two-photon PDT photo-sensitizers for the treatment of subcutaneous tumors

Science.gov (United States)

Spangler, C. W.; Rebane, A.; Starkey, J.; Drobizhev, M.

2009-06-01

New porphyrin-based photo-sensitizers have been designed, synthesized and characterized that exhibit greatly enhanced intrinsic two-photon absorption. These new photo-sensitizers have been incorporated into triad formulations that also incorporate Near-infrared (NIR) imaging agents, and small-molecule targeting agents that direct the triads to cancerous tumors' over-expressed receptor sites. PDT can be initiated deep into the tissue transparency window at 780-800 nm utilizing a regeneratively amplified Ti:sapphire laser using 100-150 fs pulses of 600-800 mW. Human tumor xenografts of human breast cancer (MDA-MB-231) and both small SCLC (NCI-H69) and NSCLC (A-459) have been successfully treated using octreotate targeting of over-expressed SST2 receptors. In particular, the lung cancer xenografts can be successfully treated by irradiating from the side of the mouse opposite the implanted tumor, thereby passing through ca. 2 cm of mouse skin, tissue and organs with no discernible damage to healthy tissue while causing regression in the tumors. These results suggest a new PDT paradigm for the noninvasive treatment of subcutaneous tumors, including the possibility that the targeting moiety could be matched to individual patient genetic profiles (patient-specific therapeutics).

New radioiodinated carboxylic and hydroxamic matrix metalloproteinase inhibitor tracers as potential tumor imaging agents

Energy Technology Data Exchange (ETDEWEB)

Oltenfreiter, Ruth E-mail: ruth.oltenfreiter@rug.ac.be; Staelens, Ludovicus; Lejeune, Annabelle; Dumont, Filip; Frankenne, Francis; Foidart, Jean-Michel; Slegers, Guido

2004-05-01

Several studies have demonstrated a positive correlation between tumor progression and expression of extracellular proteinases such as matrix metalloproteinases (MMPs). MMP-2 and MMP-9 have become attractive targets for cancer research because of their increased expression in human malignant tumor tissues of various organs, providing a target for medical imaging techniques. Radioiodinated carboxylic and hydroxamic MMP inhibitors 2-(4'-[{sup 123}I]iodo-biphenyl-4-sulfonylamino)-3-(1H-indol-3-yl)-propionic acid (9) and 2-(4'-[{sup 123}I]iodo-biphenyl-4-sulfonylamino)-3-(1H-indol-3-yl)-propionamide (11) were synthesized by electrophilic aromatic substitution of the tributylstannyl derivatives and resulted in radiochemical yields of 60% {+-} 5% (n = 3) and 70% {+-} 5% (n = 6), respectively. In vitro zymography and enzyme assays showed high inhibition capacities of the inhibitors on gelatinases. In vivo biodistribution showed no long-term accumulation in organs and the possibility to accumulate in the tumor. These results warrant further studies of radioiodinated carboxylic and hydroxamic MMP inhibitor tracers as potential SPECT tumor imaging agents.

New radioiodinated carboxylic and hydroxamic matrix metalloproteinase inhibitor tracers as potential tumor imaging agents

International Nuclear Information System (INIS)

Oltenfreiter, Ruth; Staelens, Ludovicus; Lejeune, Annabelle; Dumont, Filip; Frankenne, Francis; Foidart, Jean-Michel; Slegers, Guido

2004-01-01

Several studies have demonstrated a positive correlation between tumor progression and expression of extracellular proteinases such as matrix metalloproteinases (MMPs). MMP-2 and MMP-9 have become attractive targets for cancer research because of their increased expression in human malignant tumor tissues of various organs, providing a target for medical imaging techniques. Radioiodinated carboxylic and hydroxamic MMP inhibitors 2-(4'-[ 123 I]iodo-biphenyl-4-sulfonylamino)-3-(1H-indol-3-yl)-propionic acid (9) and 2-(4'-[ 123 I]iodo-biphenyl-4-sulfonylamino)-3-(1H-indol-3-yl)-propionamide (11) were synthesized by electrophilic aromatic substitution of the tributylstannyl derivatives and resulted in radiochemical yields of 60% ± 5% (n = 3) and 70% ± 5% (n = 6), respectively. In vitro zymography and enzyme assays showed high inhibition capacities of the inhibitors on gelatinases. In vivo biodistribution showed no long-term accumulation in organs and the possibility to accumulate in the tumor. These results warrant further studies of radioiodinated carboxylic and hydroxamic MMP inhibitor tracers as potential SPECT tumor imaging agents

Mesoporous composite nanoparticles for dual-modality ultrasound/magnetic resonance imaging and synergistic chemo-/thermotherapy against deep tumors

Directory of Open Access Journals (Sweden)

Zhang N

2017-10-01

Full Text Available Nan Zhang,1 Ronghui Wang,2 Junnian Hao,1 Yang Yang,1 Hongmi Zou,3 Zhigang Wang1 1Chongqing Key Laboratory of Ultrasound Molecular Imaging, Second Affiliated Hospital of Chongqing Medical University, Chongqing Medical University, Chongqing, 2Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 3Department of Ophthalmology, Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China Abstract: High-intensity focused ultrasound (HIFU is a promising and noninvasive treatment for solid tumors, which has been explored for potential clinical applications. However, the clinical applications of HIFU for large and deep tumors such as hepatocellular carcinoma (HCC are severely limited by unsatisfactory imaging guidance, long therapeutic times, and damage to normal tissue around the tumor due to the high power applied. In this study, we developed doxorubicin/perfluorohexane-encapsulated hollow mesoporous Prussian blue nanoparticles (HMPBs-DOX/PFH as theranostic agents, which can effectively guide HIFU therapy and enhance its therapeutic effects in combination with chemotherapy, by decreasing the cavitation threshold. We investigated the effects of this agent on ultrasound and magnetic resonance imaging in vitro and in vivo. In addition, we showed a highly efficient HIFU therapeutic effect against HCC tumors, as well as controlled drug release, owing to the phase-transitional performance of the PFH. We therefore conclude that HMPB-DOX/PFH is a safe and efficient nanoplatform, which holds significant promise for cancer theranostics against deep tumors in clinical settings. Keywords: high-intensity focused ultrasound, HIFU, hollow mesoporous Prussian blue nanoplatforms, hepatocellular carcinoma, dual-modality imaging, synergistic chemo-/thermotherapy, theranostics

Suppression of tumor growth, invasion and angiogenesis of human gastric cancer by adenovirus-mediated expression of NK4

NARCIS (Netherlands)

Heideman, Daniëlle A. M.; van Beusechem, Victor W.; Bloemena, Elisabeth; Snijders, Peter J. F.; Craanen, Mikael E.; Offerhaus, G. Johan A.; Derksen, Patrick W. B.; de Bruin, Michiel; Witlox, M. Adhiambo; Molenaar, Bonnie; Meijer, Chris J. L. M.; Gerritsen, Winald R.

2004-01-01

Background To improve the prognosis of patients with gastric cancer it is important to develop novel treatment modalities targeting the malignant behavior of tumor cells. Concerning this, NK4, which acts as HGF-antagonist and angiogenesis inhibitor, might be a potential therapeutic agent for gastric

Potential of Icariin Metabolites from Epimedium koreanum Nakai as Antidiabetic Therapeutic Agents

Directory of Open Access Journals (Sweden)

Da Hye Kim

2017-06-01

Full Text Available The therapeutic properties of Epimedium koreanum are presumed to be due to the flavonoid component icariin, which has been reported to have broad pharmacological potential and has demonstrated anti-diabetic, anti-Alzheimer’s disease, anti-tumor, and hepatoprotective activities. Considering these therapeutic properties of icariin, its deglycosylated icaritin and glycosylated flavonoids (icaeriside II, epimedin A, epimedin B, and epimedin C were evaluated for their ability to inhibit protein tyrosine phosphatase 1B (PTP1B and α-glucosidase. The results show that icaritin and icariside II exhibit potent inhibitory activities, with 50% inhibition concentration (IC50 values of 11.59 ± 1.39 μM and 9.94 ± 0.15 μM against PTP1B and 74.42 ± 0.01 and 106.59 ± 0.44 μM against α-glucosidase, respectively. With the exceptions of icaritin and icariside II, glycosylated flavonoids did not exhibit any inhibitory effects in the two assays. Enzyme kinetics analyses revealed that icaritin and icariside II demonstrated noncompetitive-type inhibition against PTP1B, with inhibition constant (Ki values of 11.41 and 11.66 μM, respectively. Moreover, molecular docking analysis confirmed that icaritin and icariside II both occupy the same site as allosteric ligand. Thus, the molecular docking simulation results were in close agreement with the experimental data with respect to inhibition activity. In conclusion, deglycosylated metabolites of icariin from E. koreanum might offer therapeutic potential for the treatment of type 2 diabetes mellitus.

Challenges in the development of magnetic particles for therapeutic applications.

Science.gov (United States)

Barry, Stephen E

2008-09-01

Certain iron-based particle formulations have useful magnetic properties that, when combined with low toxicity and desirable pharmacokinetics, encourage their development for therapeutic applications. This mini-review begins with background information on magnetic particle use as MRI contrast agents and the influence of material size on pharmacokinetics and tissue penetration. Therapeutic investigations, including (1) the loading of bioactive materials, (2) the use of stationary, high-gradient (HG) magnetic fields to concentrate magnetic particles in tissues or to separate material bound to the particles from the body, and (3) the application of high power alternating magnetic fields (AMF) to generate heat in magnetic particles for hyperthermic therapeutic applications are then surveyed. Attention is directed mainly to cancer treatment, as selective distribution to tumors is well-suited to particulate approaches and has been a focus of most development efforts. While magnetic particles have been explored for several decades, their use in therapeutic products remains minimal; a discussion of future directions and potential ways to better leverage magnetic properties and to integrate their use into therapeutic regimens is discussed.

Phase I study of single-agent ribociclib in Japanese patients with advanced solid tumors.

Science.gov (United States)

Doi, Toshihiko; Hewes, Becker; Kakizume, Tomoyuki; Tajima, Takeshi; Ishikawa, Norifumi; Yamada, Yasuhide

2018-01-01

The cyclin D-CDK4/6-INK4-Rb pathway is frequently dysregulated in cancers. Ribociclib, an orally available, selective CDK4/6 inhibitor, showed preliminary clinical activity in a phase I study in the USA and Europe for patients with solid tumors and lymphomas. The present study aimed to determine the single-agent maximum tolerated dose (MTD) and recommended dose for expansion (RDE) in Japanese patients with advanced solid tumors. Ribociclib safety, tolerability, pharmacokinetic profile, and preliminary antitumor activity were also assessed. Japanese patients with solid tumors that had progressed on prior therapies received escalating doses of single-agent ribociclib on a 3-weeks-on/1-week-off schedule. Treatment continued until the development of toxicity or disease progression. A dose escalation was planned for patients with esophageal cancer. In the dose-escalation phase, 4 patients received 400 mg ribociclib and 13 patients received 600 mg ribociclib. Four patients experienced dose-limiting toxicities, 3 of whom were in the 600 mg group. The RDE was declared to be 600 mg, and the MTD was not determined. The most frequent adverse events were hematologic and gastrointestinal. Four patients achieved stable disease at the 600 mg dose; no patients achieved complete or partial response. All patients discontinued the study, the majority due to disease progression. No patients discontinued due to adverse events. Dose escalation was not pursued due to lack of observed efficacy in esophageal cancer. At the RDE of 600 mg/d on a 3-weeks-on/1-week-off schedule, ribociclib showed acceptable safety and tolerability profiles in Japanese patients with advanced solid tumors. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Nitric oxide: cancer target or anticancer agent?

Science.gov (United States)

Mocellin, Simone

2009-03-01

Despite the improved understanding of nitric oxide (NO) biology and the large amount of preclinical experiments testing its role in cancer development and progression, it is still debated whether NO should be considered a potential anticancer agent or instead a carcinogen. The complexity of NO effects within a cell and the variability of the final biological outcome depending upon NO levels makes it highly challenging to determine the therapeutic value of interfering with the activity of this intriguing gaseous messenger. This uncertainty has so far halted the clinical implementation of NO-based therapeutics in the field of oncology. Accordingly, only an in depth knowledge of the mechanisms leading to experimental tumor regression or progression in response to NO will allow us to exploit this molecule to fight cancer.

Vascular-targeted photodynamic therapy with BF2-chelated Tetraaryl-Azadipyrromethene agents: a multi-modality molecular imaging approach to therapeutic assessment.

LENUS (Irish Health Repository)

Byrne, A T

2009-11-03

Photodynamic therapy (PDT) is a treatment modality for a range of diseases including cancer. The BF(2)-chelated tetraaryl-azadipyrromethenes (ADPMs) are an emerging class of non-porphyrin PDT agent, which have previously shown excellent photochemical and photophysical properties for therapeutic application. Herein, in vivo efficacy and mechanism of action studies have been completed for the lead agent, ADMP06.

Mathematical modeling of tumor-induced immunosuppression by myeloid-derived suppressor cells: Implications for therapeutic targeting strategies.

Science.gov (United States)

Shariatpanahi, Seyed Peyman; Shariatpanahi, Seyed Pooya; Madjidzadeh, Keivan; Hassan, Moustapha; Abedi-Valugerdi, Manuchehr

2018-04-07

Myeloid-derived suppressor cells (MDSCs) belong to immature myeloid cells that are generated and accumulated during the tumor development. MDSCs strongly suppress the anti-tumor immunity and provide conditions for tumor progression and metastasis. In this study, we present a mathematical model based on ordinary differential equations (ODE) to describe tumor-induced immunosuppression caused by MDSCs. The model consists of four equations and incorporates tumor cells, cytotoxic T cells (CTLs), natural killer (NK) cells and MDSCs. We also provide simulation models that evaluate or predict the effects of anti-MDSC drugs (e.g., l-arginine and 5-Fluorouracil (5-FU)) on the tumor growth and the restoration of anti-tumor immunity. The simulated results obtained using our model were in good agreement with the corresponding experimental findings on the expansion of splenic MDSCs, immunosuppressive effects of these cells at the tumor site and effectiveness of l-arginine and 5-FU on the re-establishment of antitumor immunity. Regarding this latter issue, our predictive simulation results demonstrated that intermittent therapy with low-dose 5-FU alone could eradicate the tumors irrespective of their origins and types. Furthermore, at the time of tumor eradication, the number of CTLs prevailed over that of cancer cells and the number of splenic MDSCs returned to the normal levels. Finally, our predictive simulation results also showed that the addition of l-arginine supplementation to the intermittent 5-FU therapy reduced the time of the tumor eradication and the number of iterations for 5-FU treatment. Thus, the present mathematical model provides important implications for designing new therapeutic strategies that aim to restore antitumor immunity by targeting MDSCs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Small molecule inhibitor screening identifified HSP90 inhibitor 17-AAG as potential therapeutic agent for gallbladder cancer.

Science.gov (United States)

Weber, Helga; Valbuena, José R; Barbhuiya, Mustafa A; Stein, Stefan; Kunkel, Hana; García, Patricia; Bizama, Carolina; Riquelme, Ismael; Espinoza, Jaime A; Kurtz, Stephen E; Tyner, Jeffrey W; Calderon, Juan Francisco; Corvalán, Alejandro H; Grez, Manuel; Pandey, Akhilesh; Leal-Rojas, Pamela; Roa, Juan C

2017-04-18

Gallbladder cancer (GBC) is a lethal cancer with poor prognosis associated with high invasiveness and poor response to chemotherapy and radiotherapy. New therapeutic approaches are urgently needed in order to improve survival and response rates of GBC patients. We screened 130 small molecule inhibitors on a panel of seven GBC cell lines and identified the HSP90 inhibitor 17-AAG as one of the most potent inhibitory drugs across the different lines. We tested the antitumor efficacy of 17-AAG and geldanamycin (GA) in vitro and in a subcutaneous preclinical tumor model NOD-SCID mice. We also evaluated the expression of HSP90 by immunohistochemistry in human GBC tumors.In vitro assays showed that 17-AAG and GA significantly reduced the expression of HSP90 target proteins, including EGFR, AKT, phospho-AKT, Cyclin B1, phospho-ERK and Cyclin D1. These molecular changes were consistent with reduced cell viability and cell migration and promotion of G2/M cell cycle arrest and apoptosis observed in our in vitro studies.In vivo, 17-AAG showed efficacy in reducing subcutaneous tumors size, exhibiting a 69.6% reduction in tumor size in the treatment group compared to control mice (p < 0.05).The HSP90 immunohistochemical staining was seen in 182/209 cases of GBC (87%) and it was strongly expressed in 70 cases (33%), moderately in 58 cases (28%), and weakly in 54 cases (26%).Our pre-clinical observations strongly suggest that the inhibition of HSP90 function by HSP90 inhibitors is a promising therapeutic strategy for gallbladder cancer that may benefit from new HSP90 inhibitors currently in development.

Fluorescence Imaging/Agents in Tumor Resection.

Science.gov (United States)

Stummer, Walter; Suero Molina, Eric

2017-10-01

Intraoperative fluorescence imaging allows real-time identification of diseased tissue during surgery without being influenced by brain shift and surgery interruption. 5-Aminolevulinic acid, useful for malignant gliomas and other tumors, is the most broadly explored compound approved for fluorescence-guided resection. Intravenous fluorescein sodium has recently received attention, highlighting tumor tissue based on extravasation at the blood-brain barrier (defective in many brain tumors). Fluorescein in perfused brain, unselective extravasation in brain perturbed by surgery, and propagation with edema are concerns. Fluorescein is not approved but targeted fluorochromes with affinity to brain tumor cells, in development, may offer future advantages. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Mapping In Vivo Tumor Oxygenation within Viable Tumor by 19F-MRI and Multispectral Analysis

Directory of Open Access Journals (Sweden)

Yunzhou Shi

2013-11-01

Full Text Available Quantifying oxygenation in viable tumor remains a major obstacle toward a better understanding of the tumor microenvironment and improving treatment strategies. Current techniques are often complicated by tumor heterogeneity. Herein, a novel in vivo approach that combines 19F magnetic resonance imaging (19F-MRIR1 mapping with diffusionbased multispectral (MS analysis is introduced. This approach restricts the partial pressure of oxygen (pO2 measurements to viable tumor, the tissue of therapeutic interest. The technique exhibited sufficient sensitivity to detect a breathing gas challenge in a xenograft tumor model, and the hypoxic region measured by MS 19F-MRI was strongly correlated with histologic estimates of hypoxia. This approach was then applied to address the effects of antivascular agents on tumor oxygenation, which is a research question that is still under debate. The technique was used to monitor longitudinal pO2 changes in response to an antibody to vascular endothelial growth factor (B20.4.1.1 and a selective dual phosphoinositide 3-kinase/mammalian target of rapamycin inhibitor (GDC-0980. GDC-0980 reduced viable tumor pO2 during a 3-day treatment period, and a significant reduction was also produced by B20.4.1.1. Overall, this method provides an unprecedented view of viable tumor pO2 and contributes to a greater understanding of the effects of antivascular therapies on the tumor's microenvironment.

Evaluation of the therapeutic efficacy of a VEGFR2-blocking antibody using sodium-iodide symporter molecular imaging in a tumor xenograft model

Energy Technology Data Exchange (ETDEWEB)

Cheong, Su-Jin; Lee, Chang-Moon; Kim, Eun-Mi [Department of Nuclear Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Cyclotron Research Center, Chonbuk National University Hospital, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Uhm, Tai-Boong [Faculty of Biological Science, Chonbuk National University, Jeonju-si, jeonbuk 561-756 (Korea, Republic of); Jeong, Hwan-Jeong, E-mail: jayjeong@chonbuk.ac.k [Department of Nuclear Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Cyclotron Research Center, Chonbuk National University Hospital, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Kim, Dong Wook; Lim, Seok Tae; Sohn, Myung-Hee [Department of Nuclear Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Cyclotron Research Center, Chonbuk National University Hospital, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of)

2011-01-15

Purpose: Vascular endothelial growth factor receptor 2-blocking antibody (DC101) has inhibitory effects on tumor growth and angiogenesis in vivo. The human sodium/iodide symporter (hNIS) gene has been shown to be a useful molecular imaging reporter gene. Here, we investigated the evaluation of therapeutic efficacy by molecular imaging in reporter gene transfected tumor xenografts using a gamma imaging system. Methods: The hNIS gene was transfected into MDA-MB-231 cells using Lipofectamine. The correlation between the number of MDA-MB-231-hNIS cells and the uptake of {sup 99m}Tc-pertechnetate or {sup 125}I was investigated in vitro by gamma imaging and counting. MDA-MB-231-hNIS cells were injected subcutaneously into mice. When the tumor volume reached 180-200 mm{sup 3}, we randomly assigned five animals to each of three groups representing different tumor therapies; no DC101 (control), 100 {mu}g, or 150 {mu}g DC101/mouse. One week and 2 weeks after the first injection of DC101, gamma imaging was performed. Mice were sacrificed 2 weeks after the first injection of DC101. The tumor tissues were used for reverse transcriptase-polymerase chain reaction (RT-PCR) and CD31 staining. Results: Uptake of {sup 125}I and {sup 99m}Tc-pertechnetate into MDA-MB-231-hNIS cells in vitro showed correlation with the number of cells. In DC101 treatment groups, the mean tumor volume was smaller than that of the control mice. Furthermore, tumor uptake of {sup 125}I was lower than in the controls. The CD31 staining and RT-PCR assay results showed that vessel formation and expression of the hNIS gene were significantly reduced in the tumor tissues of treatment groups. Conclusion: This study demonstrated the power of molecular imaging using a gamma imaging system for evaluating the therapeutic efficacy of an antitumor treatment. Molecular imaging systems may be useful in evaluation and development of effective diagnostic and/or therapeutic antibodies for specific target molecules.

Tumor cell-targeted delivery of CRISPR/Cas9 by aptamer-functionalized lipopolymer for therapeutic genome editing of VEGFA in osteosarcoma.

Science.gov (United States)

Liang, Chao; Li, Fangfei; Wang, Luyao; Zhang, Zong-Kang; Wang, Chao; He, Bing; Li, Jie; Chen, Zhihao; Shaikh, Atik Badshah; Liu, Jin; Wu, Xiaohao; Peng, Songlin; Dang, Lei; Guo, Baosheng; He, Xiaojuan; Au, D W T; Lu, Cheng; Zhu, Hailong; Zhang, Bao-Ting; Lu, Aiping; Zhang, Ge

2017-12-01

Osteosarcoma (OS) is a highly aggressive pediatric cancer, characterized by frequent lung metastasis and pathologic bone destruction. Vascular endothelial growth factor A (VEGFA), highly expressed in OS, not only contributes to angiogenesis within the tumor microenvironment via paracrine stimulation of vascular endothelial cells, but also acts as an autocrine survival factor for tumor cell themselves, thus making it a promising therapeutic target for OS. CRISPR/Cas9 is a versatile genome editing technology and holds tremendous promise for cancer treatment. However, a major bottleneck to achieve the therapeutic potential of the CRISPR/Cas9 is the lack of in vivo tumor-targeted delivery systems. Here, we screened an OS cell-specific aptamer (LC09) and developed a LC09-functionalized PEG-PEI-Cholesterol (PPC) lipopolymer encapsulating CRISPR/Cas9 plasmids encoding VEGFA gRNA and Cas9. Our results demonstrated that LC09 facilitated selective distribution of CRISPR/Cas9 in both orthotopic OS and lung metastasis, leading to effective VEGFA genome editing in tumor, decreased VEGFA expression and secretion, inhibited orthotopic OS malignancy and lung metastasis, as well as reduced angiogenesis and bone lesion with no detectable toxicity. The delivery system simultaneously restrained autocrine and paracrine VEGFA signaling in tumor cells and could facilitate translating CRISPR-Cas9 into clinical cancer treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Protective and therapeutic effects of cannabis plant extract on liver cancer induced by dimethylnitrosamine in mice

Directory of Open Access Journals (Sweden)

Neveen Abd El Moneim Hussein

2014-09-01

Conclusion: The protective effect of cannabis extract is more pronounced in group taking cannabis before DMNA. Cannabinoids might exert their anti-tumor effects by the direct induction of apoptosis and can decrease telomerase activity by inhibiting the expression of the TERT gene. Coordination between inhibition of telomerase activity and induction of apoptosis might be a potential therapeutic agent for cancer treatment.

Radiation-induced tumors of the nervous system

International Nuclear Information System (INIS)

Bernstein, M.; Laperriere, N.

1991-01-01

Therapeutic and nontherapeutic ionizing radiation has long been recognized as a putative carcinogenic agent, but the evidence that radiation causes tumors is circumstantial at worst and statistically significant at best. There are no distinct histological, biochemical, cytogenetic, or clinical criteria that can be used to determine if an individual tumor was caused directly by previous irradiation of the anatomic area. Additional supportive evidence for radiation-induced tumors includes a position correlation between radiation dose and tumor incidence (usually in the low dose range) and experimental induction of the same neoplasm in appropriate animal models. even if these criteria are fulfilled, coincidental development of a second tumor can never be discounted in an individual patient, particularly if there is an underlying diathesis to develop multiple tumors of different histology, such as in Recklinghausen's disease, or if there is an strong family history for the development of neoplastic disease. In this paper, the authors critically evaluate the available evidence to support the hypothesis that radiation induces tumors in the nervous system. The current concepts of radiation carcinogenesis are discussed and are followed by a discussion of animal data and clinical experience in humans. Finally, a brief discussion on treatment of radiation-induced nervous system tumors is presented

From Chemotherapy to Combined Targeted Therapeutics: In Vitro and in Vivo Models to Decipher Intra-tumor Heterogeneity

Directory of Open Access Journals (Sweden)

Guido Gambara

2018-02-01

Full Text Available Recent advances in next-generation sequencing and other omics technologies capable to map cell fate provide increasing evidence on the crucial role of intra-tumor heterogeneity (ITH for cancer progression. The different facets of ITH, from genomic to microenvironmental heterogeneity and the hierarchical cellular architecture originating from the cancer stem cell compartment, contribute to the range of tumor phenotypes. Decoding these complex data resulting from the analysis of tumor tissue complexity poses a challenge for developing novel therapeutic strategies that can counteract tumor evolution and cellular plasticity. To achieve this aim, the development of in vitro and in vivo cancer models that resemble the complexity of ITH is crucial in understanding the interplay of cells and their (microenvironment and, consequently, in testing the efficacy of new targeted treatments and novel strategies of tailoring combinations of treatments to the individual composition of the tumor. This challenging approach may be an important cornerstone in overcoming the development of pharmaco-resistances during multiple lines of treatment. In this paper, we report the latest advances in patient-derived 3D (PD3D cell cultures and patient-derived tumor xenografts (PDX as in vitro and in vivo models that can retain the genetic and phenotypic heterogeneity of the tumor tissue.

The diagnosis and therapeutic gain using US, CT and MRI. Submucosal tumors in stomach and duodenum

Energy Technology Data Exchange (ETDEWEB)

Miyamoto, Shinichi; Nawano, Shigeru; Tajiri, Hisao; Boku, Narikazu; Muto, Manabu; Ohtsu, Atsushi; Yoshida, Shigeaki [National Cancer Center, Kashiwa, Chiba (Japan). Hospital East; Moriyama, Noriyuki

1999-02-01

The usefulness of the ultrasonography (US), the computed tomography (CT) and the magnetic resonance imaging (MRI) was examined. The subjects were 19 patients with submucosal leiomyoma and leiomyosarcoma in the stomach and duodenum which had surgery and were histologically diagnosed in the National Cancer Center Hospital. The detectability of the primary foci was 50% (8/16) in US, and 93% (13/14) in EUS (the endoscopic ultrasonography) which makes the structure of the stomach wall and the continuity of tumors clear. CT could detect the primary foci in 94% (16/17) and was excellent to know not only the presence of the remote metastases but also the exact size and expanse of the tumors. In all cases of leiomyoma, tumors were leiomyosarcoma when the internal structure was diagnosed to be heterogeneous by both EUS and CT, or either of them. The qualitative image diagnosis is not always easy in gastrointestinal submucosal tumors, but it is important to generally diagnose by the combination with several examinations in order to select the suitable therapeutic method. (K.H.)

Galectin-3 as a Potential Therapeutic Target in Tumors Arising from Malignant Endothelia

Directory of Open Access Journals (Sweden)

Kim D. Johnson

2007-08-01

Full Text Available Angiosarcoma (ASA in humans, hemangiosarcoma (HSA in dogs are deadly neoplastic diseases characterized by an aggressive growth of malignant cells with endothelial phenotype, widespread metastasis, poor response to chemotherapy. Galectin-3 (Gal-3, a p-galactoside-binding lectin implicated in tumor progression, metastasis, endothelial cell biology, angiogenesis, regulation of apoptosis, neoplastic cell response to cytotoxic drugs, has not been studied before in tumors arising from malignant endothelia. Here, we tested the hypothesis that Gal-3 could be widely expressed in human ASA, canine HSA, could play an important role in malignant endothelial cell biology. Immunohistochemical analysis demonstrated that 100% of the human ASA (10 of 10, canine HSA (17 of 17 samples analyzed expressed Gal-3. Two carbohydrate-based Gal-3 inhibitors, modified citrus pectin (MCP, lactulosyl-l-leucine (LL, caused a dose-dependent reduction of SVR murine ASA cell clonogenic survival through the inhibition of Gal-3 antiapoptotic function. Furthermore, both MCP, LL sensitized SVR cells to the cytotoxic drug doxorubicin to a degree sufficient to reduce the in vitro IC50 of doxorubicin by 10.7-fold, 3.64old, respectively. These results highlight the important role of Gal-3 in the biology of ASA, identify Gal-3 as a potential therapeutic target in tumors arising from malignant endothelial cells.

Tumor regression following intravenous administration of lactoferrin- and lactoferricin-bearing dendriplexes.

Science.gov (United States)

Lim, Li Ying; Koh, Pei Yin; Somani, Sukrut; Al Robaian, Majed; Karim, Reatul; Yean, Yi Lyn; Mitchell, Jennifer; Tate, Rothwelle J; Edrada-Ebel, RuAngelie; Blatchford, David R; Mullin, Margaret; Dufès, Christine

2015-08-01

The possibility of using gene therapy for the treatment of cancer is limited by the lack of safe, intravenously administered delivery systems able to selectively deliver therapeutic genes to tumors. In this study, we investigated if the conjugation of the polypropylenimine dendrimer to lactoferrin and lactoferricin, whose receptors are overexpressed on cancer cells, could result in a selective gene delivery to tumors and a subsequently enhanced therapeutic efficacy. The conjugation of lactoferrin and lactoferricin to the dendrimer significantly increased the gene expression in the tumor while decreasing the non-specific gene expression in the liver. Consequently, the intravenous administration of the targeted dendriplexes encoding TNFα led to the complete suppression of 60% of A431 tumors and up to 50% of B16-F10 tumors over one month. The treatment was well tolerated by the animals. These results suggest that these novel lactoferrin- and lactoferricin-bearing dendrimers are promising gene delivery systems for cancer therapy. Specific targeting of cancer cells should enhance the delivery of chemotherapeutic agents. This is especially true for gene delivery. In this article, the authors utilized a dendrimer-based system and conjugated this with lactoferrin and lactoferricin to deliver anti-tumor genes. The positive findings in animal studies should provide the basis for further clinical studies. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Recent advances in dendrimer-based nanovectors for tumor-targeted drug and gene delivery

Science.gov (United States)

Kesharwani, Prashant; Iyer, Arun K.

2015-01-01

Advances in the application of nanotechnology in medicine have given rise to multifunctional smart nanocarriers that can be engineered with tunable physicochemical characteristics to deliver one or more therapeutic agent(s) safely and selectively to cancer cells, including intracellular organelle-specific targeting. Dendrimers having properties resembling biomolecules, with well-defined 3D nanopolymeric architectures, are emerging as a highly attractive class of drug and gene delivery vector. The presence of numerous peripheral functional groups on hyperbranched dendrimers affords efficient conjugation of targeting ligands and biomarkers that can recognize and bind to receptors overexpressed on cancer cells for tumor-cell-specific delivery. The present review compiles the recent advances in dendrimer-mediated drug and gene delivery to tumors by passive and active targeting principles with illustrative examples. PMID:25555748

Non-invasive focused ultrasound-based synergistic treatment of brain tumors

Directory of Open Access Journals (Sweden)

Ya-Jui Lin

2016-09-01

The success of FUS BBB disruption in delivering a variety of therapeutic molecules into brain tumors has recently been demonstrated in an animal model. In this paper the authors review a number of critical studies that have demonstrated successful outcomes, including enhancement of the delivery of traditional clinically used chemotherapeutic agents or application of novel nanocarrier designs for actively transporting drugs, or extending drug half-lives to significantly improve treatment efficacy in preclinical animal models.

Synthesis and Biological Evaluation of Novel Furozan-Based Nitric Oxide-Releasing Derivatives of Oridonin as Potential Anti-Tumor Agents

Directory of Open Access Journals (Sweden)

Hao Cai

2012-06-01

Full Text Available To search for novel nitric oxide (NO releasing anti-tumor agents, a series of novel furoxan/oridonin hybrids were designed and synthesized. Firstly, the nitrate/nitrite levels in the cell lysates were tested by a Griess assay and the results showed that these furoxan-based NO-releasing derivatives could produce high levels of NO in vitro. Then the anti-proliferative activity of these hybrids against four human cancer cell lines was also determined, among which, 9h exhibited the most potential anti-tumor activity with IC₅₀ values of 1.82 µM against K562, 1.81 µM against MGC-803 and 0.86 µM against Bel-7402, respectively. Preliminary structure-activity relationship was concluded based on the experimental data obtained. These results suggested that NO-donor/natural product hybrids may provide a promising approach for the discovery of novel anti-tumor agents.

Frontiers in nano-therapeutics

CERN Document Server

Tasnim, Nishat; Sai Krishna, Katla; Kalagara, Sudhakar; Narayan, Mahesh; Noveron, Juan C; Joddar, Binata

2017-01-01

This brief highlights recent research advances in the area of nano-therapeutics. Nanotechnology holds immense potential for application in a wide range of biological and engineering applications such as molecular sensors for disease diagnosis, therapeutic agents for the treatment of diseases, a vehicle for delivering therapeutics and imaging agents for theranostic applications, both in-vitro and in-vivo. The brief is grouped into the following sections namely, A) Discrete Nanosystems ; B) Anisotropic Nanoparticles; C) Nano-films/coated/layered and D) Nano-composites.

Epigenetics, Nervous System Tumors, and Cancer Stem Cells

Energy Technology Data Exchange (ETDEWEB)

Qureshi, Irfan A. [Rosyln and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Mehler, Mark F., E-mail: mark.mehler@einstein.yu.edu [Rosyln and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States)

2011-09-13

Recent advances have begun to elucidate how epigenetic regulatory mechanisms are responsible for establishing and maintaining cell identity during development and adult life and how the disruption of these processes is, not surprisingly, one of the hallmarks of cancer. In this review, we describe the major epigenetic mechanisms (i.e., DNA methylation, histone and chromatin modification, non-coding RNA deployment, RNA editing, and nuclear reorganization) and discuss the broad spectrum of epigenetic alterations that have been uncovered in pediatric and adult nervous system tumors. We also highlight emerging evidence that suggests epigenetic deregulation is a characteristic feature of so-called cancer stem cells (CSCs), which are thought to be present in a range of nervous system tumors and responsible for tumor maintenance, progression, treatment resistance, and recurrence. We believe that better understanding how epigenetic mechanisms operate in neural cells and identifying the etiologies and consequences of epigenetic deregulation in tumor cells and CSCs, in particular, are likely to promote the development of enhanced molecular diagnostics and more targeted and effective therapeutic agents for treating recalcitrant nervous system tumors.

Epigenetics, Nervous System Tumors, and Cancer Stem Cells

International Nuclear Information System (INIS)

Qureshi, Irfan A.; Mehler, Mark F.

2011-01-01

Recent advances have begun to elucidate how epigenetic regulatory mechanisms are responsible for establishing and maintaining cell identity during development and adult life and how the disruption of these processes is, not surprisingly, one of the hallmarks of cancer. In this review, we describe the major epigenetic mechanisms (i.e., DNA methylation, histone and chromatin modification, non-coding RNA deployment, RNA editing, and nuclear reorganization) and discuss the broad spectrum of epigenetic alterations that have been uncovered in pediatric and adult nervous system tumors. We also highlight emerging evidence that suggests epigenetic deregulation is a characteristic feature of so-called cancer stem cells (CSCs), which are thought to be present in a range of nervous system tumors and responsible for tumor maintenance, progression, treatment resistance, and recurrence. We believe that better understanding how epigenetic mechanisms operate in neural cells and identifying the etiologies and consequences of epigenetic deregulation in tumor cells and CSCs, in particular, are likely to promote the development of enhanced molecular diagnostics and more targeted and effective therapeutic agents for treating recalcitrant nervous system tumors

Advances in the treatment of gastroenteropancreatic neuroendocrine tumors

Directory of Open Access Journals (Sweden)

Pamela L Kunz

2010-06-01

Full Text Available Pamela L Kunz, George A FisherStanford University Medical Center, CA, USAAbstract: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs are a rare and heterogeneous class of neoplasms. While surgical resection is the mainstay of treatment, non-surgical therapies play a role in the setting of unresectable and metastatic disease. The goals of medical therapy are directed both at alleviating symptoms of peptide release and shrinking tumor mass. Biotherapies such as somatostatin analogs and interferon can decrease the secretion of peptides and inhibit their end-organ effects. A second objective for treatment of unresectable GEP-NETs is limiting tumor growth. Options for limiting tumor growth include somatostatin analogs, systemic chemotherapy, locoregional therapies, ionizing radiation, external beam radiation, and newer targeted agents. In particular, angiogenesis inhibitors, tyrosine kinase inhibitors, and mTOR inhibitors have shown early promising results. The rarity of these tumors, their resistance to standard chemotherapy, and the excellent performance status of most of these patients, make a strong argument for consideration of novel therapeutic trials.Keywords: neuroendocrine, gastroenteropancreatic, carcinoid, somatostatin

Evaluation of the Combined Effects of Sonodynamic and Photodynamic Therapies in a Colon Carcinoma Tumor Model (CT26

Directory of Open Access Journals (Sweden)

Ameneh Sazgarnia

2009-12-01

Full Text Available Introduction: Photodynamic therapy is a noninvasive therapeutic method for tumors with a maximum depth of 5 mm. On the other hand, most photosensitizers are also susceptible to ultrasound waves (the basis of sonodynamic therapy. Therefore, it is expected that a combination of the two therapeutic methods will increase effectiveness of photodynamic therapies for lower doses of sensitizer and curing deeper tumors. This study evaluates the synergistic effects of photodynamic and sonodynamic therapies.     Materials and methods: The study was conducted on a colon carcinoma tumor model in Balb/c mice. The colon carcinoma tumors were induced in the mice by subcutaneous injection. Twenty four hours after intraperitoneal injection of Zinc Phthalocyanine liposome as a sensitizer, at first ultrasound irradiation with a known frequency and intensity was performed followed by illumination of the tumor area. Evaluation of the treatment efficacy was done using daily measurement of the tumors and calculation of their relative volumes. Also, all control groups were considered to confirm the effect of each therapeutic option in the study.   Results: In the first ten days post treatment, the relative volumes of all groups decreased significantly in comparison with the main control group, but the best response was observed in the photodynamic or sonodynamic therapy groups. The longest doubling time of tumor size was related to groups under photodynamic, sonodynamic and main therapies, and the shortest belonged to the control group.   Discussion and conclusion: Zinc phthalocyanine liposome is both a photosensitizer and sonsensitizer. Photodynamic and sonodynamic therapies can be efficient in retarding tumor growth rate. In this study, combination of the two methods did not cause improved therapeutic outcomes. It is predicted that this result is related to the choice of therapeutic agents and could be optimized in future.

[Relationship between sensitivity of tumor cells to chemotherapeutic agent in vivo and in vitro: experiment with mouse lymphoma cells].

Science.gov (United States)

Li, Chuan-gang; Li, Mo-lin; Shu, Xiao-hong; Jia, Yu-jie; Liu, Yong-ji; Li, Ming

2007-06-12

To study the relationship of the sensitivity of tumor cells to chemotherapeutic agent between in vivo and in vitro. Mouse lymphoma cells of the line E14 were cultured and melphalan resistant EL4 cell line (EL4/melphalan) was established by culturing EL4 cells with continuous low-concentration and intermittent gradually-increasing-concentration of melphalan in vitro. MTT assay was used to evaluate the drug sensitivity and the resistance index of the EL4/melphalan cells to melphalan was calculated. EL4/melphalan and EL4 cells of the concentration of 5 x 10(8)/L were inoculated separately into 20 C57BL/6 mice subcutaneously. 12 days later, the EL4 and EL4/melphalan tumor-bearing mice were randomly divided into 2 groups respectively, 5 mice in each group. Treatment groups were given 7.5 mg/kg melphalan intraperitoneally, and control groups were given the same volume of normal saline. The tumor size was observed every other day. Compared with the EL4 cells, the EL4/melphalan cells had no obvious changes morphologically. They could grow in RPMI 1640 medium containing 5 mg/ml melphalan. The resistance index was 2.87 against melphalan. After the treatment of melphalan of the dose 7.5 mg/kg, the tumor sizes of the treatment groups and control groups inoculated with both EL4 cells and the EL4/melphalan cells gradually decreased at the similar speed, and about one week later all tumors disappeared. However, the tumors of the control groups grew progressively and all the mice died at last. The chemotherapeutic effects of tumors in vivo have nothing to do with the effects of the chemotherapeutic agents on tumor cells in vitro. The tumor cells resistant to melphalan in vitro remain sensitive to the drug in vivo.

Development and biological evaluation of {sup 90}Y-BPAMD as a novel bone seeking therapeutic agent

Energy Technology Data Exchange (ETDEWEB)

Rabiei, Ali; Shamsaei, Mojtaba [Amir Kabir University of Technology, Tehran (Iran, Islamic Republic of). Energy Engineering and Physics Dept.; Yousefnia, Hassan; Zolghadri, Samaneh; Jalilian, Amir Reza [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Enayati, Razieh [Islamic Azad Univ. (IAU), Tehran (Iran, Islamic Republic of). Faculty of Engineering

2016-07-01

Nowadays, the bone-seeking radiopharmaceuticals play an important role in the treatment of the bone-related pathologies. Whereas various phosphonate ligands have already been identified, a DOTA-based bisphosphonate, 4-{[(bis(phosphonomethyl))carbamoyl]methyl}-7,10-bis(carboxymethyl) -1,4,7,10-tetraazacyclododec-1-yl (BPAMD) with better characteristics has recently been synthesized. In this study, {sup 90}Y-BPAMD was developed with radiochemical purity >98% and the specific activity of 3.52 TBq/mmol in the optimized conditions as a new bone-seeking therapeutic agent. The complex demonstrated significant stability at room temperature and in human serum even after 48 h. At even low amount of hydroxyapatite (5 mg), more than 90% binding to hydroxyapatite was observed. Biodistribution studies after injection of the complex into the Syrian rats showed major accumulation of the labelled compound in the bone tissue and an insignificant uptake in the other organs all the times after injection. Generally, {sup 90}Y-BPAMD demonstrated interesting characteristics compared to the other {sup 90}Y bone-seeking agents and even {sup 166}Ho-BPAMD, and can be considered as a new bone-seeking candidate for therapeutic applications.

Mechanoregulatory tumor-stroma crosstalk in pancreatic cancer: Measurements of the effects of extracellular matrix mechanics on tumor growth behavior, and vice-versa, to inform therapeutics

Science.gov (United States)

Celli, Jonathan; Jones, Dustin; El-Hamidi, Hamid; Cramer, Gwendolyn; Hanna, William; Caide, Andrew; Jafari, Seyedehrojin

The rheological properties of the extracellular matrix (ECM) have been shown to play key roles in regulating tumor growth behavior through mechanotranduction pathways. The role of the mechanical microenvironment may be particularly important tumors of the pancreas, noted for an abundance of rigid fibrotic stroma, implicated in therapeutic resistance. At the same time, cancer cells and their stromal partners (e.g. tumor associated fibroblasts) continually alter the mechanical microenvironment in response to extracellular physical and biochemical cues as part of a two-way mechanoregulatory dialog. Here, we describe experimental studies using 3D pancreatic cell cultures with customized mechanical properties, combined with optical microrheology to provide insight into tumor-driven matrix remodeling. Quantitative microscopy provides measurements of phenotypic changes accompanying systematic variation of ECM composition in collagen and laminin-rich basement membrane admixtures, while analysis of the trajectories of passive tracer particles embedded in ECM report dynamic changes in heterogeneity, microstructure and local shear modulus accompanying both ECM stiffening (fibrosis) processes, and ECM degradation near invading cells. We gratefully acknowledge funding from the National Cancer Institute, R00CA155045 (PI: Celli).

Continued biological investigations of boron-rich oligomeric phosphate diesters (OPDs). Tumor-selective boron agents for BNCT

International Nuclear Information System (INIS)

Lee, Mark W.; Shelly, Kenneth; Kane, Robert R.; Hawthorne, M. Frederick

2006-01-01

Clinical success of Boron Neutron Capture Therapy will rely on the selective intracellular delivery of high concentrations of boron-10 to tumor tissue. In order for a boron agent to facilitate clinical success, the simultaneous needs of obtaining a high tumor dose, high tumor selectivity, and low systemic toxicity must be realized. Boron-rich oligomeric phosphate diesters (OPDs) are a class of highly water-soluble compounds containing up to 40% boron by weight. Previous work in our groups demonstrated that once placed in the cytoplasm of tumor cells, OPDs quickly accumulate within the cell nucleus. The objective of the current study was to determine the biodistribution of seven different free OPDs in BALB/c mice bearing EMT6 tumors. Fructose solutions containing between 1.4 and 6.4 micrograms of boron per gram of tissue were interveinously injected in mice seven to ten days after tumor implantation. At intervals during the study, animals were euthanized and samples of tumor, blood, liver, kidney, brain and skin were collected and analyzed for boron content using ICP-AES. Tumor boron concentrations of between 5 and 29 ppm were achieved and maintained over the 72-hour time course of each experiment. Several OPDs demonstrated high tumor selectivity with one oligomer exhibiting a tumor to blood ratio of 35:1. The apparent toxicity of each oligomer was assessed through animal behavior during the experiment and necropsy of each animal upon sacrifice. (author)

Tumor uptake of radioruthenium compounds

International Nuclear Information System (INIS)

Srivastava, S.C.; Richards, P.; Meinken, G.E.; Larson, S.M.; Grunbaum, Z.

1980-01-01

The use of ruthenium-97 as a scintigraphic agent, particularly for tumor localization, is investigated. The tumor uptake of ruthenium chloride and ruthenium-labelled transferrin is evaluated and their application as tumor-imagine agents is compared to gallium-67 citrate

Some experience with 57Co-labeled bleomycin as a tumor-seeking agent

International Nuclear Information System (INIS)

Rasker, J.J.; van de Poll, M.A.P.C.; Beekhuis, H.; Woldring, M.G.; Nieweg, H.O.

1975-01-01

Bleomycin labeled with 57 Co was used as a tumor-localizing agent in 132 patients. In patients with pulmonary tumors the primary localization concentrated radioactivity in 52 of the 54 appropriate cases; out of the 22 clinically known metastases, 19 were visible on the scan; 40 unknown metastases especially in hilus and mediastinum were found by this method and subsequently confirmed. In 22 patients with malignant lymphomas, 18 out of 22 known pathologic lymph glands above the diaphragm were visible on the scan; below the diaphragm the results of scanning in lymph glands and spleen were disappointing, probably because of the disturbing concentration of radioactivity in the kidneys, the bladder, the liver, and sometimes the gut. In 25 patients with various other tumors, 16 out of 22 known localizations above the diaphragm were visible; 2 were uncertain and 4 negative. Below the diaphragm the results were usually negative. In 24 patients with benign lesions, uptake of 57 Co-bleomycin was visible on the scintigram in 4 patients with cavitating pulmonary tuberculosis, in 2 with pulmonary infections, in 1 with Caplan lesions of rheumatoid arthritis in the lung, and in 1 with sinusitis ethmoidalis. The significance of these results is discussed

Optimizing the Delivery of Short-Lived Alpha Particle-Emitting Isotopes to Solid Tumors

International Nuclear Information System (INIS)

Adams, Gregory P.

2004-01-01

The underlying hypothesis of this project was that optimal alpha emitter-based radioimmunotherapy (RAIT) could be achieved by pairing the physical half-life of the radioisotope to the biological half-life of the targeting vehicle. The project had two specific aims. The first aim was to create and optimize the therapeutic efficacy of 211At-SAPS-C6.5 diabody conjugates. The second aim was to develop bispecific-targeting strategies that increase the specificity and efficacy of alpha-emitter-based RAIT. In the performance of the first aim, we created 211At-SAPS-C6.5 diabody conjugates that specifically targeted the HER2 tumor associated antigen. In evaluating these immunoconjugates we determined that they were capable of efficient tumor targeting and therapeutic efficacy of established human tumor xenografts growing in immunodeficient mice. We also determined that therapeutic doses were associated with late renal toxicity, likely due to the role of the kidneys in the systemic elimination o f these agents. We are currently performing more studies focused on better understanding the observed toxicity. In the second aim, we successfully generated bispecific single-chain Fv (bs-scFv) molecules that co-targeted HER2 and HER3 or HER2 and HER4. The in vitro kinetics and in vivo tumor-targeting properties of these molecules were evaluated. These studies revealed that the bs-scFv molecules selectively localized in vitro on tumor cells that expressed both antigens and were capable of effective tumor localization in in vivo studies

Optimizing the Delivery of Short-Lived Alpha Particle-Emitting Isotopes to Solid Tumors

Energy Technology Data Exchange (ETDEWEB)

Adams, Gregory P.

2004-11-24

The underlying hypothesis of this project was that optimal alpha emitter-based radioimmunotherapy (RAIT) could be achieved by pairing the physical half-life of the radioisotope to the biological half-life of the targeting vehicle. The project had two specific aims. The first aim was to create and optimize the therapeutic efficacy of 211At-SAPS-C6.5 diabody conjugates. The second aim was to develop bispecific-targeting strategies that increase the specificity and efficacy of alpha-emitter-based RAIT. In the performance of the first aim, we created 211At-SAPS-C6.5 diabody conjugates that specifically targeted the HER2 tumor associated antigen. In evaluating these immunoconjugates we determined that they were capable of efficient tumor targeting and therapeutic efficacy of established human tumor xenografts growing in immunodeficient mice. We also determined that therapeutic doses were associated with late renal toxicity, likely due to the role of the kidneys in the systemic elimination o f these agents. We are currently performing more studies focused on better understanding the observed toxicity. In the second aim, we successfully generated bispecific single-chain Fv (bs-scFv) molecules that co-targeted HER2 and HER3 or HER2 and HER4. The in vitro kinetics and in vivo tumor-targeting properties of these molecules were evaluated. These studies revealed that the bs-scFv molecules selectively localized in vitro on tumor cells that expressed both antigens and were capable of effective tumor localization in in vivo studies.

Development of NMR imaging using CEST agents: application to brain tumor in a rodent model

International Nuclear Information System (INIS)

Flament, J.

2012-01-01

The study aimed at developing saturation transfer imaging of lipoCEST contrast agents for the detection of angiogenesis in a U87 mouse brain tumor model. A lipoCEST with a sensitivity threshold of 100 pM in vitro was optimized in order to make it compatible with CEST imaging in vivo. Thanks to the development of an experimental setup dedicated to CEST imaging, we evaluated lipoCEST to detect specifically tumor angiogenesis. We demonstrated for the first time that lipoCEST visualization was feasible in vivo in a mouse brain after intravenous injection. Moreover, the integrin α v β 3 over expressed during tumor angiogenesis can be specifically targeted using a functionalized lipoCEST with RGD peptide. The specific association between the RGD-lipoCEST and its target α v β 3 was confirmed by immunohistochemical data and fluorescence microscopy. Finally, in order to tend to a molecular imaging protocol by CEST-MRI, we developed a quantification tool of lipoCEST contrast agents. This tool is based on modeling of proton exchange processes in vivo. By taking into account both B0 and B1 fields inhomogeneities which can dramatically alter CEST contrast, we showed that the accuracy of our quantification tool was 300 pM in vitro. The tool was applied on in vivo data acquired on the U87 mouse model and the maximum concentration of RGD-lipoCEST linked to their molecular targets was evaluated to 1.8 nM. (author) [fr

Near Infrared Fluorescence Imaging in Nano-Therapeutics and Photo-Thermal Evaluation

Science.gov (United States)

Vats, Mukti; Mishra, Sumit Kumar; Baghini, Mahdieh Shojaei; Chauhan, Deepak S.; Srivastava, Rohit; De, Abhijit

2017-01-01

The unresolved and paramount challenge in bio-imaging and targeted therapy is to clearly define and demarcate the physical margins of tumor tissue. The ability to outline the healthy vital tissues to be carefully navigated with transection while an intraoperative surgery procedure is performed sets up a necessary and under-researched goal. To achieve the aforementioned objectives, there is a need to optimize design considerations in order to not only obtain an effective imaging agent but to also achieve attributes like favorable water solubility, biocompatibility, high molecular brightness, and a tissue specific targeting approach. The emergence of near infra-red fluorescence (NIRF) light for tissue scale imaging owes to the provision of highly specific images of the target organ. The special characteristics of near infra-red window such as minimal auto-fluorescence, low light scattering, and absorption of biomolecules in tissue converge to form an attractive modality for cancer imaging. Imparting molecular fluorescence as an exogenous contrast agent is the most beneficial attribute of NIRF light as a clinical imaging technology. Additionally, many such agents also display therapeutic potentials as photo-thermal agents, thus meeting the dual purpose of imaging and therapy. Here, we primarily discuss molecular imaging and therapeutic potentials of two such classes of materials, i.e., inorganic NIR dyes and metallic gold nanoparticle based materials. PMID:28452928

Improved anti-tumor activity of a therapeutic melanoma vaccine through the use of the dual COX-2/5-LO inhibitor licofelone

Directory of Open Access Journals (Sweden)

Silke Neumann

2016-12-01

Full Text Available Immune-suppressive cell populations impair anti-tumor immunity and can contribute to the failure of immune therapeutic approaches. We hypothesized that the non-steroidal anti-inflammatory drug (NSAID licofelone, a dual COX-2/5-LO inhibitor, would improve therapeutic melanoma vaccination by reducing immune-suppressive cell populations. Therefore, licofelone was administered after tumor implantation, either alone or in combination with a peptide vaccine containing a long tyrosinase-related protein (TRP2-peptide and the adjuvant α-galactosylceramide, all formulated into cationic liposomes. Mice immunized with the long-peptide vaccine and licofelone showed delayed tumor growth compared to mice given the vaccine alone. This protection was associated with a lower frequency of immature myeloid cells (IMCs in the bone marrow (BM and spleen of tumor-inoculated mice. When investigating the effect of licofelone on IMCs in vitro, we found that the prostaglandin E2-induced generation of IMCs was decreased in the presence of licofelone. Furthermore, pre-incubation of BM cells differentiated under IMC-inducing conditions with licofelone reduced the secretion of cytokines interleukin (IL-10 and -6 upon LPS stimulation as compared to untreated cells. Interestingly, licofelone increased IL-6 and IL-10 secretion when administered after the LPS stimulus, demonstrating an environment-dependent effect of licofelone. Our findings support the use of licofelone to reduce tumor-promoting cell populations.

The preparation for an instant kit of 99mTc(V) DMSA as a tumor-seeking imaging agent and animal experimentation

International Nuclear Information System (INIS)

Li Yunlong; Li Hongyu; Jing Hui; Guo Hongyuan; Liu Yingmei; Zhao Hui

1997-10-01

A method for preparing an instant kit of 99m Tc(V) DMSA was described. The effect of pH on labelling efficiency of the kit was investigated. 99m Tc(V) DMSA was characterized by TLC on silica-gel sheets, eluting with n-butanol: acetic acid: water = 3:2:3 (volume ratio). Radiochemical purity and stability of 99m Tc(V) DMSA in vitro were studied. The results clearly demonstrated that the yield of 99m Tc(V) DMSA was more than 95% at pH 8∼8.5 and the agent was stable in 3 h at room temperature. Effect of temperature, moisture and luminosity on the stability of the freeze-dried kit were considered. The biological distributions of 99m Tc(V) DMSA were measured in mice bearing tumor S180. The results indicated that during 1∼6 h after i.v. injection, 99m Tc(V) DMSA was highly up taken in tumor tissue, the ratios of tumor: muscle and tumor: bone were in the ranges of 1.4∼2.4 and 1.2∼1.8, respectively. This peculiarity indicated that 99m Tc(V) DMSA has tumor-seeking property and could be used as a tumor-seeking imaging agent. (9 refs., 11 tabs.)

Vascular Targeting in Pancreatic Cancer: The Novel Tubulin-Binding Agent ZD6126 Reveals Antitumor Activity in Primary and Metastatic Tumor Models

Directory of Open Access Journals (Sweden)

Axel Kleespies

2005-10-01

Full Text Available ZD6126 is a novel vascular-targeting agent that acts by disrupting the tubulin cytoskeleton of an immature tumor endothelium, leading to an occlusion of tumor blood vessels and a subsequent tumor necrosis. We wanted to evaluate ZD6126 in primary and metastatic tumor models of human pancreatic cancer. Nude mice were injected orthotopically with L3.6pl pancreatic cancer cells. In single and multiple dosing experiments, mice received ZD6126, gemcitabine, a combination of both agents, or no treatment. For the induction of metastatic disease, additional groups of mice were injected with L3.6pl cells into the spleen. Twenty-four hours after a single-dose treatment, ZD6126 therapy led to an extensive central tumor necrosis, which was not seen after gemcitabine treatment. Multiple dosing of ZD6126 resulted in a significant growth inhibition of primary tumors and a marked reduction of spontaneous liver and lymph node metastases. Experimental metastatic disease could be significantly controlled by a combination of ZD6126 and gemcitabine, as shown by a reduction of the number and size of established liver metastases. As shown by additional in vitro and in vivo experiments, possible mechanisms involve antivascular activities and subsequent antiproliferative and proapoptotic effects of ZD6126 on tumor cells, whereas direct activities against tumor cells seem unlikely. These data highlight the antitumor and antimetastatic effects of ZD6126 in human pancreatic cancer and reveal benefits of adding ZD6126 to standard gemcitabine therapy.

A systems approach for tumor pharmacokinetics.

Directory of Open Access Journals (Sweden)

Greg Michael Thurber

Full Text Available Recent advances in genome inspired target discovery, small molecule screens, development of biological and nanotechnology have led to the introduction of a myriad of new differently sized agents into the clinic. The differences in small and large molecule delivery are becoming increasingly important in combination therapies as well as the use of drugs that modify the physiology of tumors such as anti-angiogenic treatment. The complexity of targeting has led to the development of mathematical models to facilitate understanding, but unfortunately, these studies are often only applicable to a particular molecule, making pharmacokinetic comparisons difficult. Here we develop and describe a framework for categorizing primary pharmacokinetics of drugs in tumors. For modeling purposes, we define drugs not by their mechanism of action but rather their rate-limiting step of delivery. Our simulations account for variations in perfusion, vascularization, interstitial transport, and non-linear local binding and metabolism. Based on a comparison of the fundamental rates determining uptake, drugs were classified into four categories depending on whether uptake is limited by blood flow, extravasation, interstitial diffusion, or local binding and metabolism. Simulations comparing small molecule versus macromolecular drugs show a sharp difference in distribution, which has implications for multi-drug therapies. The tissue-level distribution differs widely in tumors for small molecules versus macromolecular biologic drugs, and this should be considered in the design of agents and treatments. An example using antibodies in mouse xenografts illustrates the different in vivo behavior. This type of transport analysis can be used to aid in model development, experimental data analysis, and imaging and therapeutic agent design.

Quantitative Analysis of Survivin Protein Expression and Its Therapeutic Depletion by an Antisense Oligonucleotide in Human Lung Tumors

Directory of Open Access Journals (Sweden)

Anna L Olsen

2012-01-01

Full Text Available RNA-directed antisense and interference therapeutics are a promising treatment option for cancer. The demonstration of depletion of target proteins within human tumors in vivo using validated methodology will be a key to the application of this technology. Here, we present a flow cytometric-based approach to quantitatively determine protein levels in solid tumor material derived by fiber optic brushing (FOB of non-small cell lung cancer (NSCLC patients. Focusing upon the survivin protein, and its depletion by an antisense oligonucleotide (ASO (LY2181308, we show that we can robustly identify a subpopulation of survivin positive tumor cells in FOB samples, and, moreover, detect survivin depletion in tumor samples from a patient treated with LY2181308. Survivin depletion appears to be a result of treatment with this ASO, because a tumor treated with conventional cytotoxic chemotherapy did not exhibit a decreased percentage of survivin positive cells. Our approach is likely to be broadly applicable to, and useful for, the quantification of protein levels in tumor samples obtained as part of clinical trials and studies, facilitating the proof-of-principle testing of novel targeted therapies.

Multiple roles and therapeutic implications of Akt signaling in cancer

Directory of Open Access Journals (Sweden)

Emiliano Calvo

2009-06-01

Full Text Available Emiliano Calvo1, Victoria Bolós2, Enrique Grande21Centro Integral Oncológico Clara Campal (CiOCC, Madrid. Spain; 2Pfizer Oncology, Alcobendas-Madrid, SpainAbstract: The prominence of the PI3K-Akt signaling pathway in several tumors indicates a relationship with tumor grade and proliferation. Critical cellular processes are driven through this pathway. More detailed knowledge of the pathogenesis of tumors would enable us to design targeted drugs to block both membrane tyrosine kinase receptors and the intracellular kinases involved in the transmission of the signal. The newly approved molecular inhibitors sunitinib (an inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and other tyrosine kinase receptors, sorafenib (a serine–threonine kinase inhibitor that acts against B-Raf and temsirolimus (an mTOR inhibitor shown clinical activity in advanced kidney cancer. Chronic myeloid leukemia has changed its natural history thanks to imatinib and dasatinib, both of which inhibit the intracellular bcr/abl protein derived from the alteration in the Philadelphia chromosome. Intracellular pathways are still important in cancer development and their blockade directly affects outcome. Cross-talk has been observed but is not well understood. Vertical and horizontal pathway blockade are promising anticancer strategies. Indeed, preclinical and early clinical data suggest that combining superficial and intracellular blocking agents can synergize and leverage single-agent activity. The implication of the Akt signaling pathway in cancer is well established and has led to the development of new anticancer agents that block its activation.Keywords: Akt, cancer, therapeutic target, Akt inhibitors

An innovative pre-targeting strategy for tumor cell specific imaging and therapy.

Science.gov (United States)

Qin, Si-Yong; Peng, Meng-Yun; Rong, Lei; Jia, Hui-Zhen; Chen, Si; Cheng, Si-Xue; Feng, Jun; Zhang, Xian-Zheng

2015-09-21

A programmed pre-targeting system for tumor cell imaging and targeting therapy was established based on the "biotin-avidin" interaction. In this programmed functional system, transferrin-biotin can be actively captured by tumor cells with the overexpression of transferrin receptors, thus achieving the pre-targeting modality. Depending upon avidin-biotin recognition, the attachment of multivalent FITC-avidin to biotinylated tumor cells not only offered the rapid fluorescence labelling, but also endowed the pre-targeted cells with targeting sites for the specifically designed biotinylated peptide nano-drug. Owing to the successful pre-targeting, tumorous HepG2 and HeLa cells were effectively distinguished from the normal 3T3 cells via fluorescence imaging. In addition, the self-assembled peptide nano-drug resulted in enhanced cell apoptosis in the observed HepG2 cells. The tumor cell specific pre-targeting strategy is applicable for a variety of different imaging and therapeutic agents for tumor treatments.

Therapeutic Targeting of AXL Receptor Tyrosine Kinase Inhibits Tumor Growth and Intraperitoneal Metastasis in Ovarian Cancer Models

Directory of Open Access Journals (Sweden)

Pinar Kanlikilicer

2017-12-01

Full Text Available Despite substantial improvements in the treatment strategies, ovarian cancer is still the most lethal gynecological malignancy. Identification of drug treatable therapeutic targets and their safe and effective targeting is critical to improve patient survival in ovarian cancer. AXL receptor tyrosine kinase (RTK has been proposed to be an important therapeutic target for metastatic and advanced-stage human ovarian cancer. We found that AXL-RTK expression is associated with significantly shorter patient survival based on the The Cancer Genome Atlas patient database. To target AXL-RTK, we developed a chemically modified serum nuclease-stable AXL aptamer (AXL-APTAMER, and we evaluated its in vitro and in vivo antitumor activity using in vitro assays as well as two intraperitoneal animal models. AXL-aptamer treatment inhibited the phosphorylation and the activity of AXL, impaired the migration and invasion ability of ovarian cancer cells, and led to the inhibition of tumor growth and number of intraperitoneal metastatic nodules, which was associated with the inhibition of AXL activity and angiogenesis in tumors. When combined with paclitaxel, in vivo systemic (intravenous [i.v.] administration of AXL-aptamer treatment markedly enhanced the antitumor efficacy of paclitaxel in mice. Taken together, our data indicate that AXL-aptamers successfully target in vivo AXL-RTK and inhibit its AXL activity and tumor growth and progression, representing a promising strategy for the treatment of ovarian cancer.

Influence of vascular normalization on interstitial flow and delivery of liposomes in tumors

International Nuclear Information System (INIS)

Ozturk, Deniz; Yonucu, Sirin; Yilmaz, Defne; Unlu, Mehmet Burcin

2015-01-01

Elevated interstitial fluid pressure is one of the barriers of drug delivery in solid tumors. Recent studies have shown that normalization of tumor vasculature by anti-angiogenic factors may improve the delivery of conventional cytotoxic drugs, possibly by increasing blood flow, decreasing interstitial fluid pressure, and enhancing the convective transvascular transport of drug molecules. Delivery of large therapeutic agents such as nanoparticles and liposomes might also benefit from normalization therapy since their transport depends primarily on convection. In this study, a mathematical model is presented to provide supporting evidence that normalization therapy may improve the delivery of 100 nm liposomes into solid tumors, by both increasing the total drug extravasation and providing a more homogeneous drug distribution within the tumor. However these beneficial effects largely depend on tumor size and are stronger for tumors within a certain size range. It is shown that this size effect may persist under different microenvironmental conditions and for tumors with irregular margins or heterogeneous blood supply. (paper)

Magnetic resonance characterization of tumor microvessels in experimental breast tumors using a slow clearance blood pool contrast agent (carboxymethyldextran-A2-Gd-DOTA) with histopathological correlation

International Nuclear Information System (INIS)

Preda, Anda; Novikov, Viktor; Moeglich, Martina; Turetschek, Karl; Shames, David M.; Roberts, Timothy P.L.; Brasch, Robert C.; Floyd, Eugenia; Carter, Wayne O.; Corot, Claire

2005-01-01

Carboxymethyldextran (CMD)-A2-Gd-DOTA, a slow clearance blood pool contrast agent with a molecular weight of 52.1 kDa, designed to have intravascular residence for more than 1 h, was evaluated for its potential to characterize and differentiate the microvessels of malignant and benign breast tumors. Precontrast single-slice inversion-recovery snapshot FLASH and dynamic contrast-enhanced MRI using an axial T1-weighted three-dimensional spoiled gradient recalled sequence was performed in 30 Sprague-Dawley rats with chemically induced breast tumors. Endothelial transfer coefficient and fractional plasma volume of the breast tumors were estimated from MRI data acquired with CMD-A2-Gd-DOTA enhancement injected at a dose of 0.1 mmol Gd/kg body weight using a two-compartment bidirectional model of the tumor tissue. The correlation between MRI microvessel characteristics and histopathological tumor grade was determined using the Scarff-Bloom-Richardson method. Using CMD-A2-Gd-DOTA, no significant correlations were found between the MR-estimated endothelial transfer coefficient or plasma volumes with histological tumor grade. Analysis of CMD-A2-Gd-DOTA-enhanced MR kinetic data failed to demonstrate feasibility for the differentiation of benign from malignant tumors or for image-based tumor grading. (orig.)

Biomarkers for hepatocellular carcinoma: diagnostic and therapeutic utility

Directory of Open Access Journals (Sweden)

Ferrín G

2015-04-01

Full Text Available Gustavo Ferrín,1,2 Patricia Aguilar-Melero,1 Manuel Rodríguez-Perálvarez,1,2 José Luis Montero-Álvarez,1,2 Manuel de la Mata1,2 1Liver Unit, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC, Hospital Universitario Reina Sofía, Córdoba, Spain; 2Centro de Investigación Biomédica en Red (CIBER, Enfermedades Hepáticas y Digestivas, Instituto de Salud Carlos III, Madrid, Spain Abstract: Because of the high prevalence and associated-mortality of hepatocellular carcinoma (HCC, early diagnosis of the disease is vital for patient survival. In this regard, tumor size is one of the two main prognostic factors for surgical resection, which constitutes the only curative treatment for HCC along with liver transplantation. However, techniques for HCC surveillance and diagnosis that are currently used in clinical practice have certain limitations that may be inherent to the tumor development. Thus, it is important to continue efforts in the search for biomarkers that increase diagnostic accuracy for HCC. In this review, we focus on different biological sources of candidate biomarkers for HCC diagnosis. Although those biomarkers identified from biological samples obtained by noninvasive methods have greater diagnostic value, we have also considered those obtained from liver tissue because of their potential therapeutic value. To date, sorafenib is the only US Food and Drug Administration-approved antineoplastic for HCC. However, this therapeutic agent shows very low tumor response rates and frequently causes acquired resistance in HCC patients. We discuss the use of HCC biomarkers as therapeutic targets themselves, or as targets to increase sensitivity to sorafenib treatment. Keywords: diagnosis, sorafenib, therapy

Profiling Prostate Cancer Therapeutic Resistance

OpenAIRE

Cameron A. Wade; Natasha Kyprianou

2018-01-01

The major challenge in the treatment of patients with advanced lethal prostate cancer is therapeutic resistance to androgen-deprivation therapy (ADT) and chemotherapy. Overriding this resistance requires understanding of the driving mechanisms of the tumor microenvironment, not just the androgen receptor (AR)-signaling cascade, that facilitate therapeutic resistance in order to identify new drug targets. The tumor microenvironment enables key signaling pathways promoting cancer cell survival ...

166Ho-HA evaluation as therapeutic agent for rheumatoid arthritis treatment

International Nuclear Information System (INIS)

Chandia, M.C.; Errazu, X.C.; Pinto, L.N.; Godoy, N.O.; Avila, M.J.; Mendoza, P.; Mendoza, J.; Jofre, J.; Sirraalta, P.

2002-01-01

Aim: Rheumatoid arthritis is a limiting disease having, among its pathological features, the inflammation of synovial tissue with progressive and later destruction of the articulation. This leads to joint deformation and loss of its function, generating pain and reducing the mobility of the affected articulation. The aim was to evaluate 166 Ho-Hydroxyapatite ( 166 Ho-HA) as potential radiopharmaceutical for the symptomatic treatment of chronic and acute arthritis. Materials and Methods: Holmiun-166 was produced by irradiation of Ho 2 O 3 at La Reina Research Reactor, Nuclear Chilean Energy Commission. Hydroxyapatite was in-house synthesized. Its labelling and quality controls follows the internationally accepted procedures. An antigen's arthritis was induced to eight New Zealand rabbits with the 166 Ho-HA radiochemical being administered thereafter in two dosage modalities (single and double). The compound therapeutic efficiency was evaluated based upon clinical improvement and images from the inflamated articulation using 67 Ga citrate before and after 166 Ho-HA injection. Results: The radiochemical purity of the inoculated compound was greater than 98% as measured under sterility conditions. Clinically, an inflammation reduction (2 cm), appetite improvement and general well being was observed. The 166 Ho-HA distribution and localization was monitored using gamma camera images taken at 4 and 24 h. There was no evidence of extra articular leakage. From the 67 Ga citrate imaging, the acute group shows an overall improvement of well being corresponding to a lesser uptake at the inflamated articulation, regarding to the chronic group. The 166 Ho-HA double doses, compared to the single doses, suggest a reduced uptake of 67 Ga citrate at the inflamated tissue, meaning an increased therapeutic effect. Conclusions: 166 Ho-HA is useful as therapeutic agent for the symptomatic treatment of rheumatoid arthritis as shown by imaging and clinical examination

166 Ho-HA Evaluation as therapeutic agent for rheumatoid arthritis treatment

International Nuclear Information System (INIS)

Chandia, M; Errazu, X; Mendoza, P; Troncoso, F; Jofre, J; Sierralta, P

2003-01-01

Aim: Rheumatoid arthritis is a limiting disease having, among its pathological features, the inflammation of synovial tissue with progressive and later destruction of the articulation. This lead to joint deformation and loss of its function, generating pain and reducing the mobility of the affected articulation. The aim was to evaluate 166 Ho-Hydroxyapatite ( 166 Ho-HA) as potential radiopharmaceutical for the syntomatic treatment of chronic and acute arthritis Materials and Methods: 166 Holmiun was produced by irradiation of Ho 2 O 3 at La Reina Research Reactor, Nuclear Chilean Energy Commission. Hydroxyapatite was in-house synthetized. Its labelling and quality controls follows the internationally accepted procedures. An antigen arthritis was induced to eight New Zealand rabbits with the 166 Ho-HA radiochemical being administred thereafter in two dosage modalities (single and double). The compound therapeutic efficiency was evaluated based upon clinical improvement and images from the inflamated articulation using 67 Ga citrate before and after 166 Ho-HA injection. Results: The radiochemical purity of the innoculated compound was greater than 98% as measured under sterility conditions. Clinically, an inflamation reduction (2 cm), appetite improvement and general well being was observed. The 166 Ho-HA distribution and localization was monitored using gamma camera images taken at 4 and 24 h. There was no evidence of extraarticular leakage. From the 67 Ga citrate imaging, the acute group shows an overall improvement of well being corresponding to a lesser uptake at the inflamated articulation, regarding to the chronic group. The 166 Ho-HA double dosis, compared to the single dosis, suggest a reduced uptake of 67 Ga citrate at the inflamated tissue, meaning an increased therapeutic effect. Conclusions: 166 Ho-HA is usefull as therapeutic agent for the syntomatic treatment of rheumatoideal arthritis as shown by imaging and clinical examination (author)

Biochemical Stability Analysis of Nano Scaled Contrast Agents Used in Biomolecular Imaging Detection of Tumor Cells

Science.gov (United States)

Kim, Jennifer; Kyung, Richard

Imaging contrast agents are materials used to improve the visibility of internal body structures in the imaging process. Many agents that are used for contrast enhancement are now studied empirically and computationally by researchers. Among various imaging techniques, magnetic resonance imaging (MRI) has become a major diagnostic tool in many clinical specialties due to its non-invasive characteristic and its safeness in regards to ionizing radiation exposure. Recently, researchers have prepared aqueous fullerene nanoparticles using electrochemical methods. In this paper, computational simulations of thermodynamic stabilities of nano scaled contrast agents that can be used in biomolecular imaging detection of tumor cells are presented using nanomaterials such as fluorescent functionalized fullerenes. In addition, the stability and safety of different types of contrast agents composed of metal oxide a, b, and c are tested in the imaging process. Through analysis of the computational simulations, the stabilities of the contrast agents, determined by optimized energies of the conformations, are presented. The resulting numerical data are compared. In addition, Density Functional Theory (DFT) is used in order to model the electron properties of the compound.

[ManNAc, a new therapeutic agent to reduce Angptl4-induced proteinuria in MCD].

Science.gov (United States)

Clément, Lionel; Macé, Camille

2016-01-01

Current therapies used in minimal change disease (MCD) were originally designed to cure other diseases. They are only partially efficient, and present inconvenient side effects. Therefore, understanding the molecular mechanisms implicated in the pathogenesis of proteinuria in MCD could lead to new therapeutic strategies. A new experimental transgenic rat model of human MCD was generated. These NPHS2-Angptl4 transgenic rats over-express two different forms of the glycoprotein Angptl4 from the podocyte. The majority of the protein shows a lack of sialylation that is implicated in the pathogenesis of proteinuria. Supplementation of ManNAc, a precursor of sialic acid, significantly reduces albuminuria in those rats by increasing sialylation of the hyposialylated form of Angptl4. After treatment of the first episode of MCD with glucocorticoids in patients, ManNAc could be used as a maintenance drug, especially to reduce the frequency and intensity of relapse. ManNAc is a promising therapeutic agent for patients with MCD. © 2016 médecine/sciences – Inserm.

Metabolic and improved organ scan studies. II. Nitrogen-13 labeled compounds used as in-vivo probes for enzyme therapy and as tumor localizing and organ imaging agents

International Nuclear Information System (INIS)

Anon.

1976-01-01

A number of 13 N-labeled compounds have been enzymatically synthesized and are being evaluated as tumor and/or organ localizing agents. 13 N-Ammonia, produced after cyclotron generation of 13 N-nitrate and subsequent reduction was used to enzymatically aminate the appropriate substrate to yield 13 N-L-glutamic acid, L-glutamine, L-asparagine, L-valine, L-leucine and L-alanine. The use of 13 N-asparagine as a myocardial scanning agent and as a tumor localizing agent in asparaginase-sensitive tumors is discussed. Two imaging devices were used to study the effectiveness of the compounds as localizing agents. For static whole body distribution studies, a dual-detector high energy gamma ray (HEG) rectilinear scanner, equipped with constant response collimators was employed. The uniformity of response of this system permits quantitative determination of the amount of 13 N activity present in the organ or tumor of interest. The total organ kinetic imaging monitor (TOKIM) gamma camera system was used for dynamic studies covering smaller areas of the subject's body

In vitro and in vivo anti-tumor effect of metformin as a novel therapeutic agent in human oral squamous cell carcinoma

International Nuclear Information System (INIS)

Luo, Qingqiong; Hu, Dan; Hu, Shuiqing; Yan, Ming; Sun, Zujun; Chen, Fuxiang

2012-01-01

Metformin, which is widely used as an antidiabetic agent, has recently been reported to reduce cancer risk and improve prognosis in certain malignancies. However, the specific mechanisms underlying the effect of metformin on the development and progression of several cancers including oral squamous cell carcinoma (OSCC) remain unclear. In the present study, we investigated the effects of metformin on OSCC cells in vitro and in vivo. OSCC cells treated with or without metformin were counted using a hemocytometer. The clonogenic ability of OSCC cells after metformin treatment was determined by colony formation assay. Cell cycle progression and apoptosis were assessed by flow cytometry, and the activation of related signaling pathways was examined by immunoblotting. The in vivo anti-tumor effect of metformin was examined using a xenograft mouse model. Immunohistochemistry and TUNEL staining were used to determine the expression of cyclin D1 and the presence of apoptotic cells in tumors from mice treated with or without metformin. Metformin inhibited proliferation in the OSCC cell lines CAL27, WSU-HN6 and SCC25 in a time- and dose-dependent manner, and significantly reduced the colony formation of OSCC cells in vitro. Metformin induced an apparent cell cycle arrest at the G0/G1 phase, which was accompanied by an obvious activation of the AMP kinase pathway and a strongly decreased activation of mammalian target of rapamycin and S6 kinase. Metformin treatment led to a remarkable decrease of cyclin D1, cyclin-dependent kinase (CDK) 4 and CDK6 protein levels and phosphorylation of retinoblastoma protein, but did not affect p21 or p27 protein expression in OSCC cells. In addition, metformin induced apoptosis in OSCC cells, significantly down-regulating the anti-apoptotic proteins Bcl-2 and Bcl-xL and up-regulating the pro-apoptotic protein Bax. Metformin also markedly reduced the expression of cyclin D1 and increased the numbers of apoptotic cells in vivo, thus inhibiting

Inducing death in tumor cells: roles of the inhibitor of apoptosis proteins [version 1; referees: 3 approved

Directory of Open Access Journals (Sweden)

Darren Finlay

2017-04-01

Full Text Available The heterogeneous group of diseases collectively termed cancer results not just from aberrant cellular proliferation but also from a lack of accompanying homeostatic cell death. Indeed, cancer cells regularly acquire resistance to programmed cell death, or apoptosis, which not only supports cancer progression but also leads to resistance to therapeutic agents. Thus, various approaches have been undertaken in order to induce apoptosis in tumor cells for therapeutic purposes. Here, we will focus our discussion on agents that directly affect the apoptotic machinery itself rather than on drugs that induce apoptosis in tumor cells indirectly, such as by DNA damage or kinase dependency inhibition. As the roles of the Bcl-2 family have been extensively studied and reviewed recently, we will focus in this review specifically on the inhibitor of apoptosis protein (IAP family. IAPs are a disparate group of proteins that all contain a baculovirus IAP repeat domain, which is important for the inhibition of apoptosis in some, but not all, family members. We describe each of the family members with respect to their structural and functional similarities and differences and their respective roles in cancer. Finally, we also review the current state of IAPs as targets for anti-cancer therapeutics and discuss the current clinical state of IAP antagonists.

Integrated genomics of ovarian xenograft tumor progression and chemotherapy response

International Nuclear Information System (INIS)

Stuckey, Ashley; Brodsky, Alexander S; Fischer, Andrew; Miller, Daniel H; Hillenmeyer, Sara; Kim, Kyu K; Ritz, Anna; Singh, Rakesh K; Raphael, Benjamin J; Brard, Laurent

2011-01-01

Ovarian cancer is the most deadly gynecological cancer with a very poor prognosis. Xenograft mouse models have proven to be one very useful tool in testing candidate therapeutic agents and gene function in vivo. In this study we identify genes and gene networks important for the efficacy of a pre-clinical anti-tumor therapeutic, MT19c. In order to understand how ovarian xenograft tumors may be growing and responding to anti-tumor therapeutics, we used genome-wide mRNA expression and DNA copy number measurements to identify key genes and pathways that may be critical for SKOV-3 xenograft tumor progression. We compared SKOV-3 xenografts treated with the ergocalciferol derived, MT19c, to untreated tumors collected at multiple time points. Cell viability assays were used to test the function of the PPARγ agonist, Rosiglitazone, on SKOV-3 cell growth. These data indicate that a number of known survival and growth pathways including Notch signaling and general apoptosis factors are differentially expressed in treated vs. untreated xenografts. As tumors grow, cell cycle and DNA replication genes show increased expression, consistent with faster growth. The steroid nuclear receptor, PPARγ, was significantly up-regulated in MT19c treated xenografts. Surprisingly, stimulation of PPARγ with Rosiglitazone reduced the efficacy of MT19c and cisplatin suggesting that PPARγ is regulating a survival pathway in SKOV-3 cells. To identify which genes may be important for tumor growth and treatment response, we observed that MT19c down-regulates some high copy number genes and stimulates expression of some low copy number genes suggesting that these genes are particularly important for SKOV-3 xenograft growth and survival. We have characterized the time dependent responses of ovarian xenograft tumors to the vitamin D analog, MT19c. Our results suggest that PPARγ promotes survival for some ovarian tumor cells. We propose that a combination of regulated expression and copy number

Acute effects of vascular modifying agents in solid tumors assessed by noninvasive laser Doppler flowmetry and near infrared spectroscopy

DEFF Research Database (Denmark)

Kragh, Michael; Quistorff, Bjørn; Horsman, Michael R

2002-01-01

LDF, using a 41 degrees C heated custom-built LDF probe with four integrated laser/receiver units, and tumor blood volume was estimated by NIRS, using light guide coupled reflectance measurements at 800+/-10 nm. FAA, DMXAA, CA4DP, and HDZ significantly decreased tumor perfusion by 50%, 47%, 73......The potential of noninvasive laser Doppler flowmetry (LDF) and near infrared spectroscopy (NIRS) to detect acute effects of different vascular-modifying agents on perfusion and blood volume in tumors was evaluated. C3H mouse mammary carcinomas (approximately 200 mm(3)) in the rear foot of CDF1 mice......%, and 78%, respectively. In addition, FAA, DMXAA, and HDZ significantly reduced the blood volume within the tumor, indicating that these compounds to some degree shunted blood from the tumor to adjacent tissue, HDZ being most potent. CA4DP caused no change in the tumor blood volume, indicating...

Intratumoral distribution of {sup 64}Cu-ATSM and {sup 18}F-FDG in VX2 tumor bearing rabbit model

Energy Technology Data Exchange (ETDEWEB)

Yoo, Ran Ji; Lee, Yong Jin; Lee, Won Ho; Kim, Kyeong Min; Park, Ji Ae; Lee, Kyo Chul; Chung, Wee Sup; Kang, Joo Hyun; Lim, Sang Moo [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

2012-05-15

Imaging acquisition and analysis of hypoxic region within solid tumor is essential for understanding the microenvironment of tumor, and is also important for the establishment of proper therapeutic strategy and evaluation for radiation therapy (1-5). {sup 64}Cu-labeled diacetyl-bis (N{sub 4}-methylthiosemicarbazone) ({sup 64}Cu-ATSM) is a promising agent for imaging of hypoxic tissues and internal radiation therapy for tumor. In this study, we obtained PET/CT images of tumor using {sup 64}Cu-ATSM and {sup 18}F-FDG, and then evaluated the distribution of hypoxic region after comparing with oxygen partial pressure in VX2 tumor bearing rabbit model. MR images are also obtained for precise anatomical information

Growth/differentiation factor-5: a candidate therapeutic agent for periodontal regeneration? A review of pre-clinical data.

Science.gov (United States)

Moore, Yolanda R; Dickinson, Douglas P; Wikesjö, Ulf M E

2010-03-01

Therapeutic concepts involving the application of matrix, growth and differentiation factors have been advocated in support of periodontal wound healing/regeneration. Growth/differentiation factor-5 (GDF-5), a member of the bone morphogenetic protein family, represents one such factor. The purpose of this review is to provide a background of the therapeutic effects of GDF-5 expressed in various musculoskeletal settings using small and large animal platforms. A comprehensive literature search was conducted to identify all reports in the English language evaluating GDF-5 using the PubMed and Google search engines, and a manual search of the reference lists from the electronically retrieved reports. Two reviewers independently screened the titles and abstracts from a total of 69 reports, 22 of which were identified as pre-clinical (in vivo) evaluations of GDF-5. The full-length article of the 22 pre-clinical reports was then reviewed. Various applications including cranial and craniofacial bone formation, spine fusion, long bone fracture healing, cartilage, and tendon/ligament repair using a variety of small and large animal platforms evaluating GDF-5 as a therapeutic agent were identified. A majority of studies, using biomechanical, radiographic, and histological analysis, demonstrated significant dose-dependent effects of GDF-5. These include increased/enhanced local bone formation, fracture healing/repair, and cartilage and tendon/ligament formation. GDF-5 frequently was shown to accelerate wound maturation. Several studies demonstrated GDF-5 to be a realistic alternative to autograft bone. Studies using pre-clinical models and human histology suggest GDF-5 may also increase/enhance periodontal wound healing/regeneration. GDF-5 appears a promising therapeutic agent for periodontal wound healing/regeneration as GDF-5 supports/accelerates bone and tendon/ligament formation in several musculoskeletal settings including periodontal tissues.

Bubble-generating nano-lipid carriers for ultrasound/CT imaging-guided efficient tumor therapy.

Science.gov (United States)

Zhang, Nan; Li, Jia; Hou, Ruirui; Zhang, Jiangnan; Wang, Pei; Liu, Xinyang; Zhang, Zhenzhong

2017-12-20

Ideal therapeutic effectiveness of chemotherapy is obtained only when tumor cells are exposed to a maximal drug concentration, which is often hindered by dose-limiting toxicity. We designed a bubble-generating liposomal delivery system by introducing ammonium bicarbonate and gold nanorods into folic acid-conjugated liposomes to allow both multimodal imaging and the local release of drug (doxorubicin) with hyperthermia. The key component, ammonium bicarbonate, allows a controlled, rapid release of doxorubicin to provide an effective drug concentration in the tumor microenvironment. An in vitro temperature-triggered drug release study showed that cumulative release improved more than two-fold. In addition, in vitro and in vivo studies indicated that local heat treatment or ultrasonic cavitation enhanced the therapeutic efficiency greatly. The delivery system could also serve as an excellent contrast agent to allow ultrasonic imaging and computerized tomography imaging simultaneously to further achieve the aim of accurate diagnostics. Results of this study showed that this versatile bubble-generating liposome is a promising system to provide optimal therapeutic effects that are guided by multimodal imaging. Copyright © 2017 Elsevier B.V. All rights reserved.

The dual kinase complex FAK-Src as a promising therapeutic target in cancer

Directory of Open Access Journals (Sweden)

Victoria Bolós

2010-06-01

Full Text Available Victoria Bolós1,*, Joan Manuel Gasent2,*, Sara López-Tarruella3, Enrique Grande1,#1Pfizer Oncology, Madrid, Spain; 2Hospital Gral. Universitario Marina Alta, Oncology Department, Denia Alicante, 3,#Hospital Clínico San Carlos, Oncology Department, ∗These authors contributed equally to this work, #Center affiliated to the Red Temática de Investigación Cooperativa (RD06/0020/0021. Instituto de Salud Carlos III (ISCIII, Spanish Ministry of Science and InnovationAbstract: Focal adhesion kinase (FAK and steroid receptor coactivator (Src are intracellular (nonreceptor tyrosine kinases that physically and functionally interact to promote a variety of cellular responses. Plenty of reports have already suggested an additional central role for this complex in cancer through its ability to promote proliferation and anoikis resistance in tumor cells. An important role for the FAK/Src complex in tumor angiogenesis has also been established. Furthermore, FAK and Src have been associated with solid tumor metastasis through their ability to promote the epithelial mesenchymal transition. In fact, a strong correlation between increased FAK/Src expression/phosphorylation and the invasive phenotype in human tumors has been found. Additionally, an association for FAK/Src with resistances to the current anticancer therapies has already been established. Currently, novel anticancer agents that target FAK or Src are under development in a broad variety of solid tumors. In this article we will review the normal cellular functions of the FAK/Src complex as an effector of integrin and/or tyrosine kinase receptor signaling. We will also collect data about their role in cancer and we will summarize the most recent data from the FAK and Src inhibitors under clinical and preclinical development. Furthermore, the association of both these proteins with chemotherapy and hormonal therapy resistances, as a rationale for new combined therapeutic approaches with these novel

Natural Killer (NK- and T-Cell Engaging Antibody-Derived Therapeutics

Directory of Open Access Journals (Sweden)

Christoph Stein

2012-06-01

Full Text Available Unmodified antibodies (abs have been successful in the treatment of hematologic malignancies, but less so for the treatment of solid tumors. They trigger anti-tumor effects through their Fc-domains, and one way to improve their efficacy is to optimize their interaction with the effectors through Fc-engineering. Another way to empower abs is the design of bispecific abs and related fusion proteins allowing a narrower choice of effector cells. Here we review frequently chosen classes of effector cells, as well as common trigger molecules. Natural Killer (NK- and T-cells are the most investigated populations in therapeutical approaches with bispecific agents until now. Catumaxomab, the first bispecific ab to receive drug approval, targets the tumor antigen Epithelial Cell Adhesion Molecule (EpCAM and recruits T-cells via a binding site for the cell surface protein CD3. The next generation of recombinant ab-derivatives replaces the broadly reactive Fc-domain by a binding domain for a single selected trigger. Blinatumomab is the first clinically successful member of this class, targeting cancer cells via CD19 and engaging T-cells by CD3. Other investigators have developed related recombinant fusion proteins to recruit effectors, such as NK-cells and macrophages. The first such agents currently in preclinical and clinical development will be discussed.

Ultrastructural changes in tumor cells following boron neutron capture therapy

International Nuclear Information System (INIS)

Barkla, D.H.; Brown, J.K.; Meriaty, H.; Allen, B.J.

1992-01-01

In a previous study the authors reported on morphological changes in two human melanoma cell lines treated with 10 B-phenylalanine(BPA) and Boron Neutron Capture Therapy(BNCT). The present study describes morphological changes in melanoma and glioma cell lines treated with boron-tetraphenyl porphyrin(BTPP) and BNCT. Porphyrin compounds are selectively taken up by tumor cells and have been used clinically in phototherapy treatment of cancer patients. Boronated porphyrins show good potential as therapeutic agents in BNCT treatment of human cancer patients

Detachment-induced E-cadherin expression promotes 3D tumor spheroid formation but inhibits tumor formation and metastasis of lung cancer cells.

Science.gov (United States)

Powan, Phattrakorn; Luanpitpong, Sudjit; He, Xiaoqing; Rojanasakul, Yon; Chanvorachote, Pithi

2017-11-01

The epithelial-to-mesenchymal transition is proposed to be a key mechanism responsible for metastasis-related deaths. Similarly, cancer stem cells (CSCs) have been proposed to be a key driver of tumor metastasis. However, the link between the two events and their control mechanisms is unclear. We used a three-dimensional (3D) tumor spheroid assay and other CSC-indicating assays to investigate the role of E-cadherin in CSC regulation and its association to epithelial-to-mesenchymal transition in lung cancer cells. Ectopic overexpression and knockdown of E-cadherin were found to promote and retard, respectively, the formation of tumor spheroids in vitro but had opposite effects on tumor formation and metastasis in vivo in a xenograft mouse model. We explored the discrepancy between the in vitro and in vivo results and demonstrated, for the first time, that E-cadherin is required as a component of a major survival pathway under detachment conditions. Downregulation of E-cadherin increased the stemness of lung cancer cells but had an adverse effect on their survival, particularly on non-CSCs. Such downregulation also promoted anoikis resistance and invasiveness of lung cancer cells. These results suggest that anoikis assay could be used as an alternative method for in vitro assessment of CSCs that involves dysregulated adhesion proteins. Our data also suggest that agents that restore E-cadherin expression may be used as therapeutic agents for metastatic cancers. Copyright © 2017 the American Physiological Society.

The dual kinase complex FAK-Src as a promising therapeutic target in cancer

Science.gov (United States)

Bolós, Victoria; Gasent, Joan Manuel; López-Tarruella, Sara; Grande, Enrique

2010-01-01

Focal adhesion kinase (FAK) and steroid receptor coactivator (Src) are intracellular (nonreceptor) tyrosine kinases that physically and functionally interact to promote a variety of cellular responses. Plenty of reports have already suggested an additional central role for this complex in cancer through its ability to promote proliferation and anoikis resistance in tumor cells. An important role for the FAK/Src complex in tumor angiogenesis has also been established. Furthermore, FAK and Src have been associated with solid tumor metastasis through their ability to promote the epithelial mesenchymal transition. In fact, a strong correlation between increased FAK/Src expression/phosphorylation and the invasive phenotype in human tumors has been found. Additionally, an association for FAK/Src with resistances to the current anticancer therapies has already been established. Currently, novel anticancer agents that target FAK or Src are under development in a broad variety of solid tumors. In this article we will review the normal cellular functions of the FAK/Src complex as an effector of integrin and/or tyrosine kinase receptor signaling. We will also collect data about their role in cancer and we will summarize the most recent data from the FAK and Src inhibitors under clinical and preclinical development. Furthermore, the association of both these proteins with chemotherapy and hormonal therapy resistances, as a rationale for new combined therapeutic approaches with these novel agents, to abrogate treatment associated resistances, will also be reviewed. PMID:20616959

Theranostic 2D ultrathin MnO2 nanosheets with fast responsibility to endogenous tumor microenvironment and exogenous NIR irradiation.

Science.gov (United States)

Liu, Zhuang; Zhang, Shengjian; Lin, Han; Zhao, Menglong; Yao, Heliang; Zhang, Linlin; Peng, Weijun; Chen, Yu

2018-02-01

The fabrication of functional nanoparticles with unique ultra-sensitivity to endogenous tumor microenvironment (TME) is of great significance for their improved theranostic performance and easy excretion out of the body, which has not been realized among diverse nano-sized photothermal agents for photothermal therapy (PTT) of tumor. In this work, we report on the synthesis of 2D ultrathin MnO 2 nanosheets for highly efficient PTT against tumor with ultra-sensitivity to endogenous TME. These ultrathin 2D MnO 2 nanosheets show the intriguing characteristic of disintegration and releasing of Mn 2+ in response to the mild acidic condition and elevated reducing microenvironment of TME, which has successfully realized the pH- and reducing-responsive T 1 -weighted magnetic resonance imaging of tumor. Importantly, the high PTT efficiency of 2D MnO 2 nanosheets responsive to exogenous NIR irradiation has been systematically demonstrated both in vitro and in vivo for suppressing the tumor growth. This first report on the exploring of TME-sensitive photothermal agents with concurrent diagnostic and therapeutic (theranostic) functions significantly broadens the biomedical application of 2D functional biomaterials, which also promotes the further potential clinical translations of nano-sized photothermal agents. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tumors markers

International Nuclear Information System (INIS)

Yamaguchi-Mizumoto, N.H.

1989-01-01

In order to study blood and cell components alterations (named tumor markers) that may indicate the presence of a tumor, several methods are presented. Aspects as diagnostic, prognostic, therapeutic value and clinical evaluation are discussed. (M.A.C.)

Acidity-Triggered Tumor Retention/Internalization of Chimeric Peptide for Enhanced Photodynamic Therapy and Real-Time Monitoring of Therapeutic Effects.

Science.gov (United States)

Han, Kai; Zhang, Wei-Yun; Ma, Zhao-Yu; Wang, Shi-Bo; Xu, Lu-Ming; Liu, Jia; Zhang, Xian-Zheng; Han, He-You

2017-05-17

Photodynamic therapy (PDT) holds great promise in tumor treatment. Nevertheless, it remains highly desirable to develop easy-to-fabricated PDT systems with improved tumor accumulation/internalization and timely therapeutic feedback. Here, we report a tumor-acidity-responsive chimeric peptide for enhanced PDT and noninvasive real-time apoptosis imaging. Both in vitro and in vivo studies revealed that a tumor mildly acidic microenvironment could trigger rapid protonation of carboxylate anions in chimeric peptide, which led to increased ζ potential, improved hydrophobicity, controlled size enlargement, and precise morphology switching from sphere to spherocylinder shape of the chimeric peptide. All of these factors realized superfast accumulation and prolonged retention in the tumor region, selective cellular internalization, and enhanced PDT against the tumor. Meanwhile, this chimeric peptide could further generate reactive oxygen species and initiate cell apoptosis during PDT. The subsequent formation of caspase-3 enzyme hydrolyzed the chimeric peptide, achieving a high signal/noise ratio and timely fluorescence feedback. Importantly, direct utilization of the acidity responsiveness of a biofunctional Asp-Glu-Val-Asp-Gly (DEVDG, caspase-3 enzyme substrate) peptide sequence dramatically simplified the preparation and increased the performance of the chimeric peptide furthest.

Development of a new anti-cancer agent for targeted radionuclide therapy: β- radiolabeled RAFT-RGD

International Nuclear Information System (INIS)

Petitprin, A.

2013-01-01

β-emitters radiolabeled RAFT-RGD as new agents for internal targeted radiotherapy. The αvβ3 integrin is known to play an important role in tumor-induced angiogenesis, tumor proliferation, survival and metastasis. Because of its overexpression on neo-endothelial cells such as those present in growing tumors, as well as on tumor cells of various origins, αvβ3 integrin is an attractive molecular target for diagnosis and therapy of the rapidly growing and metastatic tumors. A tetrameric RGD-based peptide, regioselectively addressable functionalized template-(cyclo-[RGDfK])4 (RAFT-RGD), specifically targets integrin αvβ3 in vitro and in vivo. RAFT-RGD has been used for tumor imaging and drug targeting. This study is the first to evaluate the therapeutic potential of the β-emitters radiolabeled tetrameric RGD peptide RAFT-RGD in a Nude mouse model of αvβ3 -expressing tumors. An injection of 37 MBq of 90 Y-RAFT-RGD or 177 Lu-RAFT-RGD in mice with αvβ3 -positive tumors caused a significant growth delay as compared with mice treated with 37 MBq of 90 Y-RAFT-RAD or 177 Lu-RAFT-RAD or untreated mice. In comparison, an injection of 30 MBq of 90 Y-RAFT-RGD had no efficacy for the treatment of αvβ3 -negative tumors. 90 Y-RAFT-RGD and 177 Lu-RAFT-RGD are potent αvβ3 -expressing tumor targeting agents for internal targeted radiotherapy. (author)

RITA displays anti-tumor activity in medulloblastomas independent of TP53 status.

Science.gov (United States)

Gottlieb, Aline; Althoff, Kristina; Grunewald, Laura; Thor, Theresa; Odersky, Andrea; Schulte, Marc; Deubzer, Hedwig E; Heukamp, Lukas; Eggert, Angelika; Schramm, Alexander; Schulte, Johannes H; Künkele, Annette

2017-04-25

Current therapy of medulloblastoma, the most common malignant brain tumor of childhood, achieves 40-70% survival. Secondary chemotherapy resistance contributes to treatment failure, where TP53 pathway dysfunction plays a key role. MDM2 interaction with TP53 leads to its degradation. Reactivating TP53 functionality using small-molecule inhibitors, such as RITA, to disrupt TP53-MDM2 binding may have therapeutic potential. We show here that RITA decreased viability of all 4 analyzed medulloblastoma cell lines, regardless of TP53 functional status. The decrease in cell viability was accompanied in 3 of the 4 medulloblastoma cell lines by accumulation of TP53 protein in the cells and increased CDKN1A expression. RITA treatment in mouse models inhibited medulloblastoma xenograft tumor growth. These data demonstrate that RITA treatment reduces medulloblastoma cell viability in both in vitro and in vivo models, and acts independently of cellular TP53 status, identifying RITA as a potential therapeutic agent to treat medulloblastoma.

VIP as a potential therapeutic agent in gram negative sepsis.

Science.gov (United States)

Ibrahim, Hiba; Barrow, Paul; Foster, Neil

2012-12-01

Gram negative sepsis remains a high cause of mortality and places a great burden on public health finance in both the developed and developing world. Treatment of sepsis, using antibiotics, is often ineffective since pathology associated with the disease occurs due to dysregulation of the immune system (failure to return to steady state conditions) which continues after the bacteria, which induced the immune response, have been cleared. Immune modulation is therefore a rational approach to the treatment of sepsis but to date no drug has been developed which is highly effective, cheap and completely safe to use. One potential therapeutic agent is VIP, which is a natural peptide and is highly homologous in all vertebrates. In this review we will discuss the effect of VIP on components of the immune system, relevant to gram negative sepsis, and present data from animal models. Furthermore we will hypothesise on how these studies could be improved in future and speculate on the possible different ways in which VIP could be used in clinical medicine.

Hypoxia-activated pro-drug TH-302 exhibits potent tumor suppressive activity and cooperates with chemotherapy against osteosarcoma.

Science.gov (United States)

Liapis, Vasilios; Labrinidis, Agatha; Zinonos, Irene; Hay, Shelley; Ponomarev, Vladimir; Panagopoulos, Vasilios; DeNichilo, Mark; Ingman, Wendy; Atkins, Gerald J; Findlay, David M; Zannettino, Andrew C W; Evdokiou, Andreas

2015-02-01

Tumor hypoxia is a major cause of treatment failure for a variety of malignancies. However, tumor hypoxia also offers treatment opportunities, exemplified by the development compounds that target hypoxic regions within tumors. TH-302 is a pro-drug created by the conjugation of 2-nitroimidazole to bromo-isophosphoramide (Br-IPM). When TH-302 is delivered to regions of hypoxia, Br-IPM, the DNA cross linking toxin, is released. In this study we assessed the cytotoxic activity of TH-302 against osteosarcoma cells in vitro and evaluated its anticancer efficacy as a single agent, and in combination with doxorubicin, in an orthotopic mouse model of human osteosarcoma (OS). In vitro, TH-302 was potently cytotoxic to osteosarcoma cells selectively under hypoxic conditions, whereas primary normal human osteoblasts were protected. Animals transplanted with OS cells directly into their tibiae and left untreated developed mixed osteolytic/osteosclerotic bone lesions and subsequently developed lung metastases. TH-302 reduced tumor burden in bone and cooperated with doxorubicin to protect bone from osteosarcoma induced bone destruction, while it also reduced lung metastases. TH-302 may therefore be an attractive therapeutic agent with strong activity as a single agent and in combination with chemotherapy against OS. Crown Copyright © 2014. Published by Elsevier Ireland Ltd. All rights reserved.

Dynamic Measurement of Tumor Vascular Permeability and Perfusion using a Hybrid System for Simultaneous Magnetic Resonance and Fluorescence Imaging.

Science.gov (United States)

Ren, Wuwei; Elmer, Andreas; Buehlmann, David; Augath, Mark-Aurel; Vats, Divya; Ripoll, Jorge; Rudin, Markus

2016-04-01

Assessing tumor vascular features including permeability and perfusion is essential for diagnostic and therapeutic purposes. The aim of this study was to compare fluorescence and magnetic resonance imaging (MRI)-based vascular readouts in subcutaneously implanted tumors in mice by simultaneous dynamic measurement of tracer uptake using a hybrid fluorescence molecular tomography (FMT)/MRI system. Vascular permeability was measured using a mixture of extravascular imaging agents, GdDOTA and the dye Cy5.5, and perfusion using a mixture of intravascular agents, Endorem and a fluorescent probe (Angiosense). Dynamic fluorescence reflectance imaging (dFRI) was integrated into the hybrid system for high temporal resolution. Excellent correspondence between uptake curves of Cy5.5/GdDOTA and Endorem/Angiosense has been found with correlation coefficients R > 0.98. The two modalities revealed good agreement regarding permeability coefficients and centers-of-gravity of the imaging agent distribution. The FMT/dFRI protocol presented is able to accurately map physiological processes and poses an attractive alternative to MRI for characterizing tumor neoangiogenesis.

Atypical Teratoid Rhabdoid Tumor: Current Therapy and Future Directions

Energy Technology Data Exchange (ETDEWEB)

Ginn, Kevin F.; Gajjar, Amar, E-mail: amar.gajjar@stjude.org [Division of Neuro-Oncology, St. Jude Children’s Research Hospital, Memphis, TN (United States)

2012-09-12

Atypical teratoid rhabdoid tumors (ATRTs) are rare central nervous system tumors that comprise approximately 1–2% of all pediatric brain tumors; however, in patients less than 3 years of age this tumor accounts for up to 20% of cases. ATRT is characterized by loss of the long arm of chromosome 22 which results in loss of the hSNF5/INI-1 gene. INI1, a member of the SWI/SNF chromatin remodeling complex, is important in maintenance of the mitotic spindle and cell cycle control. Overall survival in ATRT is poor with median survival around 17 months. Radiation is an effective component of therapy but is avoided in patients younger than 3 years of age due to long term neurocognitive sequelae. Most long term survivors undergo radiation therapy as a part of their upfront or salvage therapy, and there is a suggestion that sequencing the radiation earlier in therapy may improve outcome. There is no standard curative chemotherapeutic regimen, but anecdotal reports advocate the use of intensive therapy with alkylating agents, high-dose methotrexate, or therapy that includes high-dose chemotherapy with stem cell rescue. Due to the rarity of this tumor and the lack of randomized controlled trials it has been challenging to define optimal therapy and advance treatment. Recent laboratory investigations have identified aberrant function and/or regulation of cyclin D1, aurora kinase, and insulin-like growth factor pathways in ATRT. There has been significant interest in identifying and testing therapeutic agents that target these pathways.

An MRI Method To Map Tumor Hypoxia Using Red Blood Cells Loaded with a pO2-Responsive Gd-Agent.

Science.gov (United States)

Di Gregorio, Enza; Ferrauto, Giuseppe; Gianolio, Eliana; Lanzardo, Stefania; Carrera, Carla; Fedeli, Franco; Aime, Silvio

2015-08-25

Hypoxia is a typical hallmark of many solid tumors and often leads to therapy resistance and the development of a more aggressive cancer phenotype. Oxygen content in tissues has been evaluated using numerous different methods for several imaging modalities, but none has yet reached the required standard of spatial and temporal resolution. Magnetic Resonance Imaging (MRI) appears to be the technique of choice and several pO2-responsive probes have been designed for it over the years. In vivo translation is often hampered in Gd-relaxation agents as it is not possible to separate effects that arise from changes in local concentration from those associated with responsive properties. A novel procedure for the MRI based assessment of hypoxia is reported herein. The method relies on the combined use of Gd-DOTP- and Gd-HPDO3A-labeled red blood cells (RBCs) where the first probe acts as a vascular oxygenation-responsive agent, while the second reports the local labeled RBC concentration in a transplanted breast tumor mouse model. The MRI assessment of oxygenation state has been validated by photoacoustic imaging and ex vivo immunofluorescence. The method refines tumor staging in preclinical models and makes possible an accurate monitoring of the relationship between oxygenation and tumor growth.

Targeting cancer chemotherapeutic agents by use of lipiodol contrast medium

International Nuclear Information System (INIS)

Konno, T.

1990-01-01

Arterially administered Lipiodol Ultrafluid contrast medium selectively remained in various malignant solid tumors because of the difference in time required for the removal of Lipiodol contrast medium from normal capillaries and tumor neovasculature. Although blood flow was maintained in the tumor, even immediately after injection Lipiodol contrast medium remained in the neovasculature of the tumor. To target anti-cancer agents to tumors by using Lipiodol contrast medium as a carrier, the characteristics of the agents were examined. Anti-cancer agents had to be soluble in Lipiodol, be stable in it, and separate gradually from it so that the anti-cancer agents would selectively remain in the tumor. These conditions were found to be necessary on the basis of the measurement of radioactivity in VX2 tumors implanted in the liver of 16 rabbits that received arterial injections of 14C-labeled doxorubicin. Antitumor activities and side effects of arterial injections of two types of anti-cancer agents were compared in 76 rabbits with VX2 tumors. Oily anti-cancer agents that had characteristics essential for targeting were compared with simple mixtures of anti-cancer agents with Lipiodol contrast medium that did not have these essential characteristics. Groups of rabbits that received oily anti-cancer agents responded significantly better than groups that received simple mixtures, and side effects were observed more frequently in the groups that received the simple mixtures. These results suggest that targeting of the anti-cancer agent to the tumor is important for treatment of solid malignant tumors

Therapeutic options for lymphangioleiomyomatosis (LAM): where we are and where we are going

Science.gov (United States)

Steagall, Wendy K; Moss, Joel

2009-01-01

Lymphangioleiomyomatosis (LAM), a multisystem disease affecting predominantly premenopausal and middle-aged women, causes progressive respiratory failure due to cystic lung destruction and is associated with lymphatic and kidney tumors. In the past, the treatment of LAM comprised exclusively anti-estrogen and related hormonal therapies. These treatments, however, have not been proven effective. In this article, we discuss new findings regarding the molecular mechanisms involved in the regulation of LAM cell growth, which may offer opportunities to develop effective and targeted therapeutic agents. PMID:20948684

Modeling protective anti-tumor immunity via preventative cancer vaccines using a hybrid agent-based and delay differential equation approach.

Science.gov (United States)

Kim, Peter S; Lee, Peter P

2012-01-01

A next generation approach to cancer envisions developing preventative vaccinations to stimulate a person's immune cells, particularly cytotoxic T lymphocytes (CTLs), to eliminate incipient tumors before clinical detection. The purpose of our study is to quantitatively assess whether such an approach would be feasible, and if so, how many anti-cancer CTLs would have to be primed against tumor antigen to provide significant protection. To understand the relevant dynamics, we develop a two-compartment model of tumor-immune interactions at the tumor site and the draining lymph node. We model interactions at the tumor site using an agent-based model (ABM) and dynamics in the lymph node using a system of delay differential equations (DDEs). We combine the models into a hybrid ABM-DDE system and investigate dynamics over a wide range of parameters, including cell proliferation rates, tumor antigenicity, CTL recruitment times, and initial memory CTL populations. Our results indicate that an anti-cancer memory CTL pool of 3% or less can successfully eradicate a tumor population over a wide range of model parameters, implying that a vaccination approach is feasible. In addition, sensitivity analysis of our model reveals conditions that will result in rapid tumor destruction, oscillation, and polynomial rather than exponential decline in the tumor population due to tumor geometry.

Merkel Cell Carcinoma: Chemotherapy and Emerging New Therapeutic Options

International Nuclear Information System (INIS)

Desch, L.; Kunstfeld, R.

2013-01-01

Merkel cell carcinoma (MCC) is a rare neuroendocrine skin tumor that typically occurs in elderly, immunosuppressed patients. Infection with Merkel cell virus (MCV) and immunosuppression play an important role in the development of MCC. Different staging systems make it difficult to compare the existing clinical data. Furthermore, there predominantly exist single case reports and case series, but no randomized controlled trials. However, it is necessary to develop further therapy options because MCC tends to grow rapidly and metastasizes early. In the metastatic disease, therapeutic attempts were made with various chemotherapeutic combination regimens. Because of the high toxicity of these combinations, especially those established in SCLC, and regarding the unsatisfying results, the challenge is to balance the pros and cons of chemotherapy individually and carefully. Up to now, emerging new therapy options as molecular-targeted agents, for example, pipebuzone, imatinib, or somatostatin analogues as well as immunologic als, for example, imiquimod and interferons, also showed less success concerning the disease-free response rates. According to the literature, neither chemotherapy nor molecular-targeted agents or immunotherapeutic strategies have shown promising effects in the therapy of the metastatic disease of MCC so far. There is a great demand for randomized controlled studies and a need for an MCC registry and multicenter clinical trials due to the tumors curiosity.

Therapeutic Implications from Sensitivity Analysis of Tumor Angiogenesis Models

Science.gov (United States)

Poleszczuk, Jan; Hahnfeldt, Philip; Enderling, Heiko

2015-01-01

Anti-angiogenic cancer treatments induce tumor starvation and regression by targeting the tumor vasculature that delivers oxygen and nutrients. Mathematical models prove valuable tools to study the proof-of-concept, efficacy and underlying mechanisms of such treatment approaches. The effects of parameter value uncertainties for two models of tumor development under angiogenic signaling and anti-angiogenic treatment are studied. Data fitting is performed to compare predictions of both models and to obtain nominal parameter values for sensitivity analysis. Sensitivity analysis reveals that the success of different cancer treatments depends on tumor size and tumor intrinsic parameters. In particular, we show that tumors with ample vascular support can be successfully targeted with conventional cytotoxic treatments. On the other hand, tumors with curtailed vascular support are not limited by their growth rate and therefore interruption of neovascularization emerges as the most promising treatment target. PMID:25785600

Dendritic-cell-based immunotherapy evokes potent anti-tumor immune responses in CD105+ human renal cancer stem cells.

Science.gov (United States)

Zhang, Xiao-Fei; Weng, De-Sheng; Pan, Ke; Zhou, Zi-Qi; Pan, Qiu-Zhong; Zhao, Jing-Jing; Tang, Yan; Jiang, Shan-Shan; Chen, Chang-Long; Li, Yong-Qiang; Zhang, Hong-Xia; Chang, Alfred E; Wicha, Max S; Zeng, Yi-Xin; Li, Qiao; Xia, Jian-Chuan

2017-11-01

Cancer stem cells (CSCs) are responsible for tumor initiation, progression, and resistance to therapeutic agents; they are usually less sensitive to conventional cancer therapies, and could cause tumor relapse. An ideal therapeutic strategy would therefore be to selectively target and destroy CSCs, thereby preventing tumor relapse. The aim of the present study was to evaluate the effectiveness of dendritic cells (DCs) pulsed with antigen derived from CD105+ human renal cell carcinoma (RCC) CSCs against renal cancer cells in vitro and in vivo. We identified "stem-like" characteristics of CD105+ cells in two human RCC cell lines: A498 and SK-RC-39. Loading with cell lysates did not change the characteristics of the DCs. However, DCs loaded with lysates derived from CD105+ CSCs induced more functionally specific active T cells and specific antibodies against CSCs, and clearly depressed the tumor growth in mice. Our results could form the basis for a novel strategy to improve the efficacy of DC-based immunotherapy for human RCC. © 2017 Wiley Periodicals, Inc.

Efficacy of ONC201 in Desmoplastic Small Round Cell Tumor.

Science.gov (United States)

Hayes-Jordan, Andrea A; Ma, Xiao; Menegaz, Brian A; Lamhamedi-Cherradi, Salah-Eddine; Kingsley, Charles V; Benson, Jalen A; Camacho, Pamela E; Ludwig, Joseph A; Lockworth, Cynthia R; Garcia, Gloria E; Craig, Suzanne L

2018-05-01

Desmoplastic Small Round Cell Tumor (DSRCT) is a rare sarcoma tumor of adolescence and young adulthood, which harbors a recurrent chromosomal translocation between the Ewing's sarcoma gene (EWSR1) and the Wilms' tumor suppressor gene (WT1). Patients usually develop multiple abdominal tumors with liver and lymph node metastasis developing later. Survival is poor using a multimodal therapy that includes chemotherapy, radiation and surgical resection, new therapies are needed for better management of DSRCT. Triggering cell apoptosis is the scientific rationale of many cancer therapies. Here, we characterized for the first time the expression of pro-apoptotic receptors, tumor necrosis-related apoptosis-inducing ligand receptors (TRAILR1-4) within an established human DSRCT cell line and clinical samples. The molecular induction of TRAIL-mediated apoptosis using agonistic small molecule, ONC201 in vitro cell-based proliferation assay and in vivo novel orthotopic xenograft animal models of DSRCT, was able to inhibit cell proliferation that was associated with caspase activation, and tumor growth, indicating that a cell-based delivery of an apoptosis-inducing factor could be relevant therapeutic agent to control DSRCT. Copyright © 2018. Published by Elsevier Inc.

Efficacy of ONC201 in Desmoplastic Small Round Cell Tumor

Directory of Open Access Journals (Sweden)

Andrea A. Hayes-Jordan

2018-05-01

Full Text Available Desmoplastic Small Round Cell Tumor (DSRCT is a rare sarcoma tumor of adolescence and young adulthood, which harbors a recurrent chromosomal translocation between the Ewing’s sarcoma gene (EWSR1 and the Wilms’ tumor suppressor gene (WT1. Patients usually develop multiple abdominal tumors with liver and lymph node metastasis developing later. Survival is poor using a multimodal therapy that includes chemotherapy, radiation and surgical resection, new therapies are needed for better management of DSRCT. Triggering cell apoptosis is the scientific rationale of many cancer therapies. Here, we characterized for the first time the expression of pro-apoptotic receptors, tumor necrosis-related apoptosis-inducing ligand receptors (TRAILR1-4 within an established human DSRCT cell line and clinical samples. The molecular induction of TRAIL-mediated apoptosis using agonistic small molecule, ONC201 in vitro cell-based proliferation assay and in vivo novel orthotopic xenograft animal models of DSRCT, was able to inhibit cell proliferation that was associated with caspase activation, and tumor growth, indicating that a cell-based delivery of an apoptosis-inducing factor could be relevant therapeutic agent to control DSRCT.

Remote control of therapeutic T cells through a small molecule-gated chimeric receptor

Science.gov (United States)

Wu, Chia-Yung; Roybal, Kole T.; Puchner, Elias M.; Onuffer, James; Lim, Wendell A.

2016-01-01

There is growing promise in using engineered cells as therapeutic agents. For example, synthetic Chimeric Antigen Receptors (CARs) can redirect T cells to recognize and eliminate tumor cells expressing specific antigens. Despite promising clinical results, excessive activity and poor control over such engineered T cells can cause severe toxicities. We present the design of “ON-switch” CARs that enable small molecule-control over T cell therapeutic functions, while still retaining antigen specificity. In these split receptors, antigen binding and intracellular signaling components only assemble in the presence of a heterodimerizing small molecule. This titratable pharmacologic regulation could allow physicians to precisely control the timing, location, and dosage of T cell activity, thereby mitigating toxicity. This work illustrates the potential of combining cellular engineering with orthogonal chemical tools to yield safer therapeutic cells that tightly integrate both cell autonomous recognition and user control. PMID:26405231

Applications of polymeric micelles with tumor targeted in chemotherapy

International Nuclear Information System (INIS)

Ding Hui; Wang Xiaojun; Zhang Song; Liu Xinli

2012-01-01

Polymeric micelles (PMs) have gained more progress as a carrier system with the quick development of biological and nanoparticle techniques. In particular, PMs with smart targeting can deliver anti-cancer drugs directly into tumor cells at a sustained rate. PMs with core–shell structure (with diameters of 10 ∼ 100 nm) have been prepared by a variety of biodegradable and biocompatible polymers via a self-assembly process. The preparation of polymeric micelles with stimuli-responsive block copolymers or modification of target molecules on polymeric micelles’ surface are able to significantly improve the efficiency of drug delivery. Polymeric micelles, which have been considered as a novel promising drug carrier for cancer therapeutics, are rapidly evolving and being introduced in an attempt to overcome several limitations of traditional chemotherapeutics, including water solubility, tumor-specific accumulation, anti-tumor efficacy, and non-specific toxicity. This review describes the preparation of polymeric micelles and the targeted modification which greatly enhance the effects of chemotherapeutic agents.

Hsp90 as a Gatekeeper of Tumor Angiogenesis: Clinical Promise and Potential Pitfalls

Directory of Open Access Journals (Sweden)

J. E. Bohonowych

2010-01-01

Full Text Available Tumor vascularization is an essential modulator of early tumor growth, progression, and therapeutic outcome. Although antiangiogenic treatments appear promising, intrinsic and acquired tumor resistance contributes to treatment failure. Clinical inhibition of the molecular chaperone heat shock protein 90 (Hsp90 provides an opportunity to target multiple aspects of this signaling resiliency, which may elicit more robust and enduring tumor repression relative to effects elicited by specifically targeted agents. This review highlights several primary effectors of angiogenesis modulated by Hsp90 and describes the clinical challenges posed by the redundant circuitry of these pathways. The four main topics addressed include (1 Hsp90-mediated regulation of HIF/VEGF signaling, (2 chaperone-dependent regulation of HIF-independent VEGF-mediated angiogenesis, (3 Hsp90-dependent targeting of key proangiogenic receptor tyrosine kinases and modulation of drug resistance, and (4 consideration of factors such as tumor microenvironment that pose several challenges for the clinical efficacy of anti-angiogenic therapy and Hsp90-targeted strategies.

Hypoxia-Inducible Factor-1 as a Therapeutic Target in Endometrial Cancer Management

Directory of Open Access Journals (Sweden)

Laura M. S. Seeber

2010-01-01

Full Text Available In the Western world, endometrial cancer (EC is the most common malignant tumor of the female genital tract. Solid tumors like EC outgrow their vasculature resulting in hypoxia. Tumor hypoxia is important because it renders an aggressive phenotype and leads to radio- and chemo-therapy resistance. Hypoxia-inducible factor-1 (HIF-1 plays an essential role in the adaptive cellular response to hypoxia and is associated with poor clinical outcome in EC. Therefore, HIF-1 could be an attractive therapeutic target. Selective HIF-1 inhibitors have not been identified. A number of nonselective inhibitors which target signaling pathways upstream or downstream HIF-1 are known to decrease HIF-1 protein levels. In clinical trials for the treatment of advanced and/or recurrent EC are the topoisomerase I inhibitor Topotecan, mTOR-inhibitor Rapamycin, and angiogenesis inhibitor Bevacizumab. Preliminary data shows encouraging results for these agents. Further work is needed to identify selective HIF-1 inhibitors and to translate these into clinical trials.

Tumor cell proliferation kinetics and tumor growth rate

Energy Technology Data Exchange (ETDEWEB)

Tubiana, M

1989-01-01

The present knowledge on the growth rate and the proliferation kinetics of human tumor is based on the measurement of the tumor doubling times (DT) in several hundred patients and on the determination of the proportion of proliferating cells with radioactive thymidine or by flow cytometry in large numbers of patients. The results show that the DT of human tumor varies widely, from less than one week to over one year with a median value of approximately 2 months. The DTs are significantly correlated with the histological type. They depend upon (1) the duration of the cell cycle whose mean duration is 2 days with small variations from tumor to tumor, (2) the proportion of proliferating cells and consequently the cell birth rate which varies widely among tumors and which is significantly correlated to the DT, (3) the cell loss factors which also vary widely and which are the greatest when proliferation is most intensive. These studies have several clinical implications: (a) they have further increased our understanding of the natural history of human tumor, (b) they have therapeutic implications since tumor responsiveness and curability by radiation and drugs are strongly influenced by the cell kinetic parameters of the tumor, (c) the proportion of proliferating cells is of great prognostic value in several types of human cancers. The investigation of the molecular defects, which are correlated with the perturbation of control of cell proliferation, should lead to significant fundamental and therapeutic advances. (orig.).

Deciphering the molecular events necessary for synergistic tumor cell apoptosis mediated by the histone deacetylase inhibitor vorinostat and the BH3 mimetic ABT-737

NARCIS (Netherlands)

Wiegmans, Adrian P.; Alsop, Amber E.; Bots, Michael; Cluse, Leonie A.; Williams, Steven P.; Banks, Kellie-Marie; Ralli, Rachael; Scott, Clare L.; Frenzel, Anna; Villunger, Andreas; Johnstone, Ricky W.

2011-01-01

The concept of personalized anticancer therapy is based on the use of targeted therapeutics through in-depth knowledge of the molecular mechanisms of action of these agents when used alone and in combination. We have identified the apoptotic proteins and pathways necessary for synergistic tumor cell

Theranostic GO-based nanohybrid for tumor induced imaging and potential combinational tumor therapy.

Science.gov (United States)

Qin, Si-Yong; Feng, Jun; Rong, Lei; Jia, Hui-Zhen; Chen, Si; Liu, Xiang-Ji; Luo, Guo-Feng; Zhuo, Ren-Xi; Zhang, Xian-Zheng

2014-02-12

Graphene oxide (GO)-based theranostic nanohybrid is designed for tumor induced imaging and potential combinational tumor therapy. The anti-tumor drug, Doxorubicin (DOX) is chemically conjugated to the poly(ethylenimine)-co-poly(ethylene glycol) (PEI-PEG) grafted GO via a MMP2-cleavable PLGLAG peptide linkage. The therapeutic efficacy of DOX is chemically locked and its intrinsic fluorescence is quenched by GO under normal physiological condition. Once stimulated by the MMP2 enzyme over-expressed in tumor tissues, the resulting peptide cleavage permits the unloading of DOX for tumor therapy and concurrent fluorescence recovery of DOX for in situ tumor cell imaging. Attractively, this PEI-bearing nanohybrid can mediate efficient DNA transfection and shows great potential for combinational drug/gene therapy. This tumor induced imaging and potential combinational therapy will open a window for tumor treatment by offering a unique theranostic approach through merging the diagnostic capability and pathology-responsive therapeutic function. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparison of cell uptake, biodistribution and tumor retention of folate-coated and PEG-coated gadolinium nanoparticles in tumor-bearing mice.

Science.gov (United States)

Oyewumi, Moses O; Yokel, Robert A; Jay, Michael; Coakley, Tricia; Mumper, Russell J

2004-03-24

The purpose of these studies was to compare the cell uptake, biodistribution and tumor retention of folate-coated and PEG-coated gadolinium (Gd) nanoparticles. Gd is a potential agent for neutron capture therapy (NCT) of tumors. Gd nanoparticles were engineered from oil-in-water microemulsion templates. To obtain folate-coated nanoparticles, a folate ligand [folic acid chemically linked to distearoylphosphatidylethanolamine (DSPE) via a PEG spacer MW 3350] was included in nanoparticle preparations. Similarly, control nanoparticles were coated with DSPE-PEG-MW 3350 (PEG-coated). Nanoparticles were characterized based on size, size distribution, morphology, biocompatibility and tumor cell uptake. In vivo studies were carried out in KB (human nasopharyngeal carcinoma) tumor-bearing athymic mice. Biodistribution and tumor retention studies were carried out at pre-determined time intervals after injection of nanoparticles (10 mg/kg). Gd nanoparticles did not aggregate platelets or activate neutrophils. The retention of nanoparticles in the blood 8, 16 and 24 h post-injection was 60%, 13% and 11% of the injected dose (ID), respectively. A maximum Gd tumor localization of 33+/-7 microg Gd/g was achieved. Both folate-coated and PEG-coated nanoparticles had comparable tumor accumulation. However, the cell uptake and tumor retention of folate-coated nanoparticles was significantly enhanced over PEG-coated nanoparticles. Thus, the benefits of folate ligand coating were to facilitate tumor cell internalization and retention of Gd-nanoparticles in the tumor tissue. The engineered nanoparticles may have potential in tumor-targeted delivery of Gd thereby enhancing the therapeutic success of NCT.

Sensitization to radiation and alkylating agents by inhibitors of poly(ADP-ribose) polymerase is enhanced in cells deficient in DNA double-strand break repair.

Science.gov (United States)

Löser, Dana A; Shibata, Atsushi; Shibata, Akiko K; Woodbine, Lisa J; Jeggo, Penny A; Chalmers, Anthony J

2010-06-01

As single agents, chemical inhibitors of poly(ADP-ribose) polymerase (PARP) are nontoxic and have clinical efficacy against BRCA1- and BRCA2-deficient tumors. PARP inhibitors also enhance the cytotoxicity of ionizing radiation and alkylating agents but will only improve clinical outcomes if tumor sensitization exceeds effects on normal tissues. It is unclear how tumor DNA repair proficiency affects the degree of sensitization. We have previously shown that the radiosensitizing effect of PARP inhibition requires DNA replication and will therefore affect rapidly proliferating tumors more than normal tissues. Because many tumors exhibit defective DNA repair, we investigated the impact of double-strand break (DSB) repair integrity on the sensitizing effects of the PARP inhibitor olaparib. Sensitization to ionizing radiation and the alkylating agent methylmethane sulfonate was enhanced in DSB repair-deficient cells. In Artemis(-/-) and ATM(-/-) mouse embryo fibroblasts, sensitization was replication dependent and associated with defective repair of replication-associated damage. Radiosensitization of Ligase IV(-/-) mouse embryo fibroblasts was independent of DNA replication and is explained by inhibition of "alternative" end joining. After methylmethane sulfonate treatment, PARP inhibition promoted replication-independent accumulation of DSB, repair of which required Ligase IV. Our findings predict that the sensitizing effects of PARP inhibitors will be more pronounced in rapidly dividing and/or DNA repair defective tumors than normal tissues and show their potential to enhance the therapeutic ratio achieved by conventional DNA-damaging agents.