Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Semliki Forest virus (SFV) vector is a transient RNA expression vector that has an inherent p53-independent apoptosis-inducing property. It is administered as recombinant SFV particles (rSFV) that undergo 1 round of replication only and express a gene cloned into the multicloning site. In our study we have investigated the ability of the SFV vector to induce apoptosis and inhibit tumour growth in rat prostate cancer (AT3-Neo) cells expressing the Bcl-2 oncogene (AT3-Bcl-2 cells), which normally inhibits apoptosis. rSFV expressing the enhanced green fluorescent protein (EGFP) gene (rSFV-EGFP), or recombinant RNA transfected into cells by electroporation, induced delayed apoptosis in AT3-Bcl-2 cells. SFV-mediated expression of a cloned pro-apoptotic Bax gene by the vector, however, enhanced apoptosis induction both in AT3-Bcl-2 cells and standard BHK-21 cells. Such Bax-expressing particles could be produced only at low titers compared to EGFP-expressing particles under standard conditions for particle production, but lowering the incubation temperature for particle production to 33 degrees C partially alleviated this effect. Bax-expressing particles were shown to inhibit the growth of AT3-Neo and AT3-Bcl-2 tumours in nude mice, as did high titre EGFP-expressing particles. It is concluded that SFV recombinant particles have potential as anti-tumour agents to treat apoptosis-resistant tumours.
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PMID:Induction of apoptosis in BCL-2-expressing rat prostate cancer cells using the Semliki Forest virus vector. 1174 46

Thalidomide--removed from widespread clinical use by 1962 because of severe teratogenicity--has antiangiogenic and immunomodulatory effects, including the inhibition of tumor necrosis alpha factor. It has now returned to practice as an effective oral agent in the management of various disease states including erythema nodosum leprosum, for which it was approved by the U.S. Food and Drug Administration in 1998, and more recently certain malignancies, including multiple myeloma. Although thalidomide's mechanism of action remains incompletely understood, considerable insight has been generated by extensive preclinical studies in multiple myeloma. Moreover, clinical trials have confirmed benefit in relapsed disease, and the role of thalidomide in treating newly diagnosed patients is currently under study. Its use in other tumors is under evaluation, with promise in renal cell carcinoma, prostate cancer, glioma, and Kaposi's sarcoma. Activity has also been demonstrated in chronic graft-versus-host disease and in symptom relief as part of palliative care.
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PMID:Thalidomide: emerging role in cancer medicine. 1181 93

There is increased interest in the treatment of cancer with thalidomide because of its antiangiogenic, immunomodulating and sedative effects. In animal models, the antitumour activity of thalidomide is dependent on the species, route of administration and coadministration of other drugs. For example, thalidomide has shown antitumour effects as a single agent in rabbits, but not in mice. In addition, the antitumour effects of the conventional cytotoxic drug cyclophosphamide and the tumour necrosis factor inducer 5,6-dimethylxanthenone-4-acetic acid (DMXAA) were found to be potentiated by thalidomide in mice bearing colon 38 adenocarcinoma tumours. Further studies have revealed that thalidomide upregulates intratumoral production of tumour necrosis factor-alpha 10-fold over that induced by DMXAA alone. Coadministration of thalidomide also significantly reduced the plasma clearance of DMXAA and cyclophosphamide. All these effects of thalidomide may contribute to the enhanced antitumour activity. Recent clinical trials of thalidomide have indicated that it has minimal anticancer activity for most patients with solid tumours when used as a single agent, although it was well tolerated. However, improved responses have been reported in patients with multiple myeloma. Palliative effects of thalidomide on cancer-related symptoms have also been observed, especially for geriatric patients with prostate cancer. Thalidomide also eliminates the dose-limiting gastrointestinal toxic effects of irinotecan. There is preliminary evidence indicating that the clearance of thalidomide may be reduced in the elderly. The exact role of thalidomide in the treatment of cancer and cancer cachexia in the elderly remains to be elucidated. However, it may have some value as part of a multimodality anticancer therapy, rather than as a single agent.
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PMID:Thalidomide in cancer treatment: a potential role in the elderly? 1195 Mar 76

Prostate cancer is the most frequently diagnosed malignancy and the second most common cause of cancer-related death in men in the United States. Unfortunately, at the current time, no curative treatments are available for metastatic prostate cancer. As is the case for most solid tumors, the recruitment of blood vessels (angiogenesis) is key for the progression and metastasis of prostate cancer. Inhibition of this process is an attractive approach to treatment. Many antiangiogenic agents are currently in clinical development. The following discussion will outline the importance of angiogenesis in the metastasis and progression of prostate cancer, summarize the current surrogate markers of angiogenesis available for the drug development of antiangiogenic agents, and review examples of investigational agents that target tumor angiogenesis (e.g., TNP-470, Thalidomide, CC5013, Carboxyamido-triazole (CAI), Endostatin. SU5416, SU6668, Bevacizumab (Anti-VEGFrhuMAb), and 2-Methoxyestradiol).
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PMID:Inhibition of angiogenesis: treatment options for patients with metastatic prostate cancer. 1209 78

Evidence indicates that androgen-sensitive prostate cancer cells have a lower malignant potential. We previously demonstrated that expression of androgen receptor (AR) by transfection of the androgen-independent prostate cancer cell line PC3 decreases invasion and adhesion of these cells through modulation of alpha6beta4 expression. Treatment with the androgen further reduced adhesion and invasion of the cells without, however, modifying alpha6beta4. Here we investigated whether the androgen has a direct effect on alpha6beta4-EGF receptor (EGFR) interaction and signalling leading to invasion of these cells. Immunoconfocal microscopy demonstrated that in control cells (PC3-Neo), alpha6beta4 and EGFR colocalize and redistribute in response to epidermal growth factor (EGF). In PC3-AR cells colocalization and redistribution between the two molecules was reduced and abolished by pre-treatment with R1881. Co-immunoprecipitation studies demonstrated that tyrosine phosphorylation of beta4 in response to EGF was reduced in PC3-AR cells compared to PC3-Neo. Immunoconfocal and co-immunoprecipitation studies demonstrated colocalization at membrane level and co-immunoprecipitation of EGFR and AR, indicating an interaction between the two proteins. PI3K activity, a key signalling pathway for invasion of these cells, was decreased in PC3-AR cells in response to EGF and further reduced by treatment with R1881. EGFR internalization was strongly reduced in PC3-AR compared with PC3-Neo cells and was reduced by treatment with R1881. In conclusion, the expression of AR by transfection in PC3 cells confers a less malignant phenotype by interfering with EGFR--alpha6beta4 interaction and signalling leading to invasion through a mechanism involving an interaction between the classic AR and EGFR.
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PMID:Androgen receptor and prostate cancer invasion. 1253 34

Thalidomide requires cytochrome P450 (CYP)-catalyzed biotransformation for its antiangiogenic property, and CYP2C19 is responsible for 5-hydroxylation and 5'-hydroxylation of thalidomide in human. This study explored a hypothesis that patients with poor metabolizing phenotype of CYP2C19 receive little benefit from thalidomide treatment and that the poor metabolizer genotype is associated with lower ability to form the metabolites. A case-control study was conducted with 63 patients with prostate cancer who had been enrolled in a randomized phase II trial of thalidomide monotherapy (200 to 1,200 mg/day). CYP2C19 polymorphism (CYP2C19(*)2, CYP2C19(*)3, CYP2C19(*)4) was compared with clinical events (prostate-specific antigen (PSA) decline) and formations of the hydroxylated metabolites. Two patients were homozygous for the variant CYP2C19(*)2 allele (poor metabolizing phenotype). Both of these were included in the 25 patients whose PSA failed to demonstrate a decline. While 32% and 48% of the patients had quantifiable levels of 5-hydroxythalidomide and cis-5'-hydroxythalidomide, respectively, these metabolite were below quantification in both poor metabolizing patients. None had CYP2C19(*)3 or CYP2C19(*)4 alleles. Although this study had no power to detect the statistical significance of the CYP2C19 genotype, the findings were consistent with our hypothesis. The role of CYP2C19 polymorphism in thalidomide treatments remains to be elucidated.
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PMID:Pharmacogenetic associations of CYP2C19 genotype with in vivo metabolisms and pharmacological effects of thalidomide. 1264 92

The antiangiogenic effects of thalidomide have been assessed in clinical trials in patients with various solid and haematological malignancies. Thalidomide blocks the activity of angiogenic agents including bFGF, VEGF and IL-6. We undertook an open-label study using thalidomide 100 mg once daily for up to 6 months in 20 men with androgen-independent prostate cancer. The mean time of study was 109 days (median 107, range 4-184 days). Patients underwent regular measurement of prostate-specific antigen (PSA), urea and electrolytes, serum bFGF and VEGF. Three men (15%) showed a decline in serum PSA of at least 50%, sustained throughout treatment. Of 16 men treated for at least 2 months, six (37.5%) showed a fall in absolute PSA by a median of 48%. Increasing levels of serum bFGF and VEGF were associated with progressive disease; five of six men who demonstrated a fall in PSA also showed a decline in bFGF and VEGF levels, and three of four men with a rising PSA showed an increase in both growth factors. Adverse effects included constipation, morning drowsiness, dizziness and rash, and resulted in withdrawal from the study by three men. Evidence of peripheral sensory neuropathy was found in nine of 13 men before treatment. In the seven men who completed six months on thalidomide, subclinical evidence of peripheral neuropathy was found in four before treatment, but in all seven at repeat testing. The findings indicate that thalidomide may be an option for patients who have failed other forms of therapy, provided close follow-up is maintained for development of peripheral neuropathy.
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PMID:An open-label phase II study of low-dose thalidomide in androgen-independent prostate cancer. 1264 16

Angiogenesis was postulated to be a critical prognostic factor and therapeutic focus for malignancy more than two decades ago. Recent studies indicate quantitative assessments of microvessel count to be an independent prognostic variable for disease-free and overall survival in a wide variety of tumors, and that angiogenesis may be a feasible target against which to intervene pharmacologically. Several new and old agents have been found to have anti-angiogenic activity and have reached clinical trial. This review will focus on four agents under investigation in the US: carboxyamido-triazole (CAI), thalidomide, TNP-470 and interleukin (IL)-12. CAI, originally identified for its anti-invasive capacity, has been shown to inhibit tumor and endothelial cell proliferation by inhibition of calcium uptake. It is administered orally, is generally well tolerated, and has been shown to induce disease stabilization and occasional reductions in tumor mass. Thalidomide was shown to inhibit growth factor-induced neovessel formation, a process that can also explain its earlier devastating clinical toxicity. It is administered orally, and is currently in phase II clinical trials for prostate cancer, glioblastoma multiforme and breast cancer. TNP-470 is a fumagillin analog that has been shown in in vivo models to be a potent inhibitor of angiogenesis at concentrations that are cytostatic to endothelial cells and tumor cells. Lastly, IL-12 may exert its anti-angiogenic effects through activation of interferon-gamma to up-regulate interferon-inducible protein-10, an anti-angiogenic cytokine. Phase I clinical trials of IL-12 have shown disease stabilization in several tumor types in response to s.c. administration or using genetically engineered IL-12-expressing patient fibroblasts. These promising new agents join the matrix metalloproteinase inhibitors as important new drugs in the anti-cancer armamentarium.
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PMID:New anti-angiogenesis agents: review of the clinical experience with carboxyamido-triazole (CAI), thalidomide, TNP-470 and interleukin-12. 1451 90

Thalidomide has previously been shown to have anti-angiogenic properties. More recently, clinical efficacy of this agent has been demonstrated in multiple myeloma and prostate cancer. Neuroblastoma is the most frequent solid tumor of the abdomen of childhood, yet children with this disease frequently have metastases at presentation. Such patients have a very poor prognosis with current therapies. Thus, new approaches are needed. We have previously shown that VEGF antagonists can inhibit neoangiogenesis and tumor growth in experimental neuroblastoma. In this study, we investigated the anti-angiogenic and anti-tumor properties of thalidomide in a xenograft model of human neuroblastoma. Tumors were induced in athymic mice using the human neuroblastoma cell line NGP. Intraperitoneal thalidomide (100 mg/kg/dose) or vehicle was administered beginning one week after implantation, and animals euthanized at six weeks. Thalidomide treatment did not significantly alter tumor growth as compared with controls. However, thalidomide suppressed angiogenesis, as demonstrated both by fluorescein angiography and immunohistochemical staining, and induced apoptosis of endothelial cells in neuroblastoma xenografts. Quantification of microvessel density demonstrated a significant reduction of vasculature in treated tumors (p<0.004). Thalidomide induced co-option of host vasculature, an effect noted previously after VEGF blockade. This study demonstrates that thalidomide has anti-angiogenic properties in experimental neuroblastoma.
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PMID:Thalidomide is anti-angiogenic in a xenograft model of neuroblastoma. 1461 37

The identification of agents with antiproliferative activity against endothelial cells has significant value for the treatment of many angiogenesis-dependent pathologies. Herein, we describe the discovery of a series of thalidomide analogues possessing inhibitory effects against both endothelial and prostate cancer cells. More specifically, several analogues exhibited low micromolar to mid-nanomolar potency in the inhibition of human microvascular endothelial cell (HMEC) proliferation, both in the presence and absence of vascular endothelial growth factor (VEGF), with the tetrafluorophthalimido class of compounds demonstrating the greatest potency. Additionally, all the compounds were screened against two different androgen independent prostate cancer cell lines (PC-3 and DU-145). Again, the tetrafluorophthalimido analogues exhibited the greatest effect with GI(50) values in the low micromolar range. Thalidomide was found to demonstrate selective inhibition of androgen receptor positive LNCaP prostate cancer cells. Furthermore, we showed that, as an example, tetrafluorophthalimido analogue 19 was able to completely inhibit the prostate specific antigen (PSA) secretion by the LNCaP cell line, while thalidomide demonstrated a 70% inhibition. We have also demonstrated that a correlation exists between HMEC and prostate cancer cell proliferation for this structural class. Altogether, our study suggests that these analogues may serve as promising leads for the development of agents that target both androgen dependent and independent prostate cancer and blood vessel growth.
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PMID:Thalidomide analogues demonstrate dual inhibition of both angiogenesis and prostate cancer. 1472 53


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