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)

Polymorphisms in the promoter regions of cytokine genes may influence prostate cancer (PC) development via regulation of the antitumor immune response and/or pathways of tumor angiogenesis. PC patients (247) and 263 controls were genotyped for interleukin (IL)-1beta-511, IL-8-251, IL-10-1082, tumor necrosis factor-alpha-308, and vascular endothelial growth factor (VEGF)-1154 single nucleotide polymorphisms. Patient control comparisons revealed that IL-8 TT and VEGF AA genotypes were decreased in patients compared with controls [23.9 versus 32.3%; P = 0.04, odds ratio (OR) = 0.66, 95% confidence interval (CI) 0.44-0.99 and 6.3 versus 12.9%; P = 0.01, OR = 0.45, 95% CI 0.24-0.86, respectively], whereas the IL-10 AA genotype was significantly increased in patients compared with controls (31.6 versus 20.6%; P = 0.01, OR = 1.78, 95% CI 1.14-2.77). Stratification according to prognostic indicators showed association between IL-8 genotype and log prostate-specific antigen level (P = 0.05). These results suggest that single nucleotide polymorphisms associated with differential production of IL-8, IL-10, and VEGF are risk factors for PC, possibly acting via their influence on angiogenesis.
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PMID:Influence of cytokine gene polymorphisms on the development of prostate cancer. 1206 76

The endothelins, a family of potent vasoconstricting peptides, have been implicated in the pathophysiology of advanced prostate cancer. Two endothelin receptors, ET-A and ET-B are found in normal prostate tissue. Malignant prostate cells are notable for the loss of ET-B receptors and increased levels of endothelin-1 [ET-1]; this distortion of the endothelin system may be a significant factor in the progression of prostate cancer. Proposed roles for endothelin in prostate cancer include growth promotion, apoptosis inhibition, bone formation, and stimulation of nociceptive receptors. ET-1 can act alone as a mitogen, but its effects are greatest as a comitogen with a variety of growth factors, including basic fibroblast growth factor, insulin-like growth factors, and platelet derived growth factor. Although their exact functions are unclear, ET-1, in conjunction with vascular endothelial growth factor, appears to play a major role in tumor angiogenesis. By a variety of methods, ET-1 alters the balance of osteoblast and osteoclasts to the favor new bone formation that is characteristic of metastatic disease. Several studies indicate that the refractory pain of metastatic cancer is related to the direct nociceptive effects ET-1. These findings suggest that ET receptors are promising therapeutic targets for pharmacologic intervention. Early clinical trials indicate that the ET-A receptor antagonist used in prostate cancer is reasonably well tolerated with mild but pervasive symptoms related to ET-1's vasoconstrictive effects. Results of ongoing clinical trials are eagerly awaited in order to see if the hypothetical promise of ET antagonism will result in clinical success.
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PMID:Endothelin-1 as a target for therapeutic intervention in prostate cancer. 1209 77

We have previously shown that CEACAM1, a cell-adhesion molecule, acts as a tumor suppressor in prostate carcinoma. Expression of CEACAM1 in prostate cancer cells suppresses their growth in vivo. However, CEACAM1 has no effect on the growth of prostate cancer cells in vitro. This difference suggests that the antitumor effect of CEACAM1 may be due to inhibition of tumor angiogenesis, perhaps by increased secretion of antiangiogenic molecules from the cells. In this study, we have demonstrated that expression of CEACAM1 in DU145 prostate cancer cells induced the production of a factor or factors that specifically blocked the growth of endothelial but not epithelial cells. Conditioned medium from the CEACAM1-expressing cells but not control luciferase-expressing cells inhibited endothelial cell migration up a gradient of stimulatory vascular endothelial growth factor in vitro and inhibited corneal neovascularization induced by basic fibroblast growth factor in vivo. Moreover, conditioned medium from CEACAM1-expressing cells induced endothelial cell apoptosis in vitro. Only medium conditioned by CEACAM1 mutants that were able to suppress tumor growth in vivo could cause endothelial cell apoptosis. These observations suggest that CEACAM1-mediated tumor suppression in vivo is, at least in part, due to the ability of CEACAM1 to inhibit tumor angiogenesis.
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PMID:Inhibition of prostate tumor angiogenesis by the tumor suppressor CEACAM1. 1212 2

Prostate cancer presents with a broad spectrum of biologic behavior, ranging from being an indolent, incidental finding to an aggressively invasive and metastatic disease. An improved understanding of the events involved in prostate cancer progression is critically important to its diagnosis and staging, as well as to the development of new therapies. Tumor progression, particularly in aggressive and malignant tumors, is associated with the induction of an angiogenic, gene-driven switch. In prostate cancer, one of the most powerful stimulators of angiogenesis is the vascular endothelial growth factor (VEGF). VEGF transcription can be induced by hypoxia through activation of the PI3 kinase pathway and hypoxia-inducible factor alpha. MMAC/PTEN (henceforth referred to as PTEN) is a recently identified tumor suppressor gene residing on chromosome 10q23, which is frequently inactivated in a wide range of human tumors, including advanced prostate cancer. The goal of this study was to determine whether PTEN inhibits angiogenesis by modulating VEGF activity. Our results showed that reintroduction of the PTEN gene into human prostate PC-3 and LNCaP cells decreased VEGF secretion, which was accompanied by various biologic activities, including inhibited endothelial cell growth and migration. PTEN expression also down-regulated VEGF mRNA levels, as detected by RT-PCR analysis. Concomitant with lessened VEGF expression was the reduction of VEGF promoter activity in PTEN-expressing cells. Our findings suggest that PTEN modulates angiogenesis by regulating VEGF expression.
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PMID:MMAC/PTEN tumor suppressor gene regulates vascular endothelial growth factor-mediated angiogenesis in prostate cancer. 1216 88

Hypoxia-induced up-regulation of vascular endothelial growth factor (VEGF) expression is a critical event leading to tumor neovascularization. Hypoxia stimulates hypoxia-inducible factor-1alpha (HIF-1alpha), a transcriptional activator of VEGF. Cyclooxygenase (COX)-2, an inducible enzyme that catalyzes the formation of prostaglandins (PGs) from arachidonic acid, is also induced by hypoxia. We reported previously that COX-2 inhibition prevents hypoxic up-regulation of VEGF in human prostate cancer cells and that prostaglandin E(2) (PGE(2)) restores hypoxic effects on VEGF. We hypothesized that PGE(2) mediates hypoxic effects on VEGF by modulating HIF-1alpha expression. Addition of PGE(2) to PC-3ML human prostate cancer cells had no effect on HIF-1alpha mRNA levels. However, PGE(2) significantly increased HIF-1alpha protein levels, particularly in the nucleus. This effect of PGE(2) largely results from the promotion of HIF-1alpha translocation from the cytosol to the nucleus. PGE(2) addition to PC-3 ML cells transfected with a GFP-HIF-1alpha vector induced a time-dependent nuclear accumulation of the HIF-1alpha protein. Two selective COX-2 inhibitors, meloxicam and NS398, decreased HIF-1alpha levels and nuclear localization, under both normoxic and hypoxic conditions. Of several prostaglandins tested, only PGE(2) reversed the effects of a COX-2 inhibitor in hypoxic cells. Finally, PGE(2) effects on HIF-1alpha were specifically inhibited by PD98059 (a MAPK inhibitor). These data demonstrate that PGE(2) production via COX-2-catalyzed pathway plays a critical role in HIF-1alpha regulation by hypoxia and imply that COX-2 inhibitors can prevent hypoxic induction of HIF-mediated gene transcription in cancer cells.
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PMID:Prostaglandin E2 induces hypoxia-inducible factor-1alpha stabilization and nuclear localization in a human prostate cancer cell line. 1240 98

In this review, the emerging evidence that excessive energy intake relative to energy expenditure increases the risk of prostate cancer is discussed. The adverse effects of energy imbalance can be inferred from an experimental study demonstrating reduced prostate tumor growth, lower circulating concentrations of insulin-like growth factor-I and decreased expression of vascular endothelial growth factor with energy restriction in transplantable tumor models. The effects of energy restriction on factors mediating greater proliferation relative to apoptosis and angiogenesis suggest that energy imbalance may act late in the carcinogenic pathway. Energy intake also has been evaluated in relation to prostate cancer risk in 23 analytic epidemiologic studies. Among studies reporting effect estimates, 8 of 14 case-control studies support a direct association [top versus bottom quantile, OR(summary) = 1.3; 95% confidence interval (CI), 1.1-1.4], but none of four cohort studies do (RR(summary) = 1.0; 95% CI, 0.8-1.2). The four case-control studies that evaluated advanced disease suggest a higher risk with higher energy intake (OR(summary) = 1.6; 95% CI, 1.2-2.0). However, none of these studies considered the balance of energy intake with body size and physical activity, the major determinants of variability in energy demand. Numerous research questions remain to be addressed, including, Which biological pathways are adversely affected by energy imbalance? Does energy imbalance act early or late in prostate carcinogenesis? What is the optimal energy balance for minimizing risk of clinically important prostate cancer? Evidence is beginning to show that energy intake in excess of expenditure may affect prostate carcinogenesis and, in particular, risk of advanced disease.
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PMID:Energy imbalance and prostate cancer. 1242 73

The interaction between cancer cells and their microenvironment is a promising area for the development of novel therapeutic anti-cancer modalities. The formation of new blood vessels, angiogenesis, is an important step in cancer progression. Angiogenesis is a complex multistep process involving close orchestration of endothelial cells, extracellular matrix, and soluble factors. Essentially every step has been found to be regulated by inducers and inhibitors. Prostate cancer has the ability to produce angiogenic factors such as metalloproteinases, vascular endothelial growth factor, fibroblast growth factor 2, transforming growth factor-beta and cyclooxygenase-2. In several studies in prostate cancer an increased microvessel density is associated with poorer prognosis. On the other hand several endogenous inhibitors of angiogenesis have been described in prostate cancer e.g., angiostatin, endostatin, prostate specific antigen (PSA), thrombospondin-1, interleukin 10, interferons and retinoids. The expanding insight in the process of angiogenesis has resulted in a large number of pharmaceutical agents that have been tested in preclinical studies and are currently tested in clinical trials. These agents inhibit endothelial cell proliferation or migration and induce apoptosis. This ultimately will affect the formation of new vessels thereby inducing tumor dormancy. Because antiangiogenic treatment is cytostatic rather than cytotoxic, patients will need long-term therapy to prevent regrowth of the tumor. Prostate cancer is an ideal tumor for antiangiogenic studies because of the availability of a reliable tumor marker, PSA, the indolent clinical course of this cancer and the low rate of proliferation even in metastatic sites. Furthermore, clinical studies showed limited side effects, which is advantageous in this elderly patient group. Whether the ultimate antiangiogenic treatment is effective as a single agent or in combination with radiation therapy, chemotherapy or immunotherapy remains to be determined.
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PMID:Angiogenesis in prostate cancer: its role in disease progression and possible therapeutic approaches. 1243 18

Bradykinin (BK) is an autocrine growth factor for lung and prostate cancers. BK also facilitates tumor extension by increasing tissue permeability and stimulating angiogenesis. Peptide BK antagonists are in development as potential new drugs for lung cancer. Newer nonpeptide BK antagonists have even higher potency against lung cancer, in vitro and in vivo. These compounds have now been applied to the study of prostate cancers, and have been found to be effective. Prostate cancer cell line PC3 is derived from a late-stage, hormone-independent, metastatic tumor; its growth is difficult to inhibit. Our established BK antagonists, while less effective against this line of prostate cancer in xenografts in nude mice than against lung cancer, are active and have led the way to development of new peptide and nonpeptide agents for prostate cancer. In addition to inhibiting cancer cell growth directly, they inhibit angiogenesis mediated by vascular endothelial growth factor, and inhibit increased tissue permeability mediated by membrane metalloproteases in these tumors. This class of compounds offers hope for development of new drugs for refractory prostate cancer.
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PMID:Bradykinin antagonists as new drugs for prostate cancer. 1248 92

All neoplasms require angiogenesis and resulting neovascularity for growth beyond 1 mm(2). Quantitative microvessel density (MVD) has been shown to provide staging and prognostic significance in human prostate cancer (CaP). recently, it has been demonstrated that loss of the wild-type allele of the p53 tumour suppressor gene results in reduced expression of thrombospondin-1 (TSP-1), a potent inhibitor of angiogenesis. There is also an increased expression of vascular endothelial growth factor which promotes neovascularization. p53 gene mutation and MVD were investigated in men with prostate cancer. Sections from 103 radical prostatectomy cases were evaluated with immunohistochemistry to detect mutant p53 proteins. Quantitative MVD was performed on the cases exhibiting p53 positive staining and compared with negative fields of similar Gleason grade on the same histologic sections. Twenty of the 103 cases (19.4%) revealed positive p53 staining nuclei. In 19 of these 20 cases, the MVD in p53 positive areas was greater than corresponding control regions (overall P<0.0001). Extent of p53 abnormality, as well as MVD, correlated with pathologic stage. These data suggest that mutations of the p53 tumour suppressor gene may be associated with increased angiogenesis in CaP. In addition to providing staging and prognostic information, this relationship potentially has therapeutic implications.
Prostate Cancer Prostatic Dis 1997 Sep
PMID:The relation of p53 protein nuclear accumulation and angiogenesis in human prostatic carcinoma. 1249 32

Studies on angiogenic cytokines usually are initially based upon their expression by available established cell lines. Our hypothesis is that established epithelial prostate cancer (CaP) cell lines do not accurately reflect angiogenic cytokine expression as compared to epithelial and stromal components of primary cultures generated from clinical CaP specimens. Serum free and growth factor free conditioned medium (CM) was collected from PC3, LNCaP, and their orthotopic selected prostate cancer sublines. Surgically acquired and pathologically confirmed neoplastic prostate tissue was selectively grown for selection of epithelial or stromal components, and CM was also collected. CM was assayed for urokinase (u-PA), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and tumor necrosis factor alpha (TNF-alpha). u-PA was expressed only by androgen independent cell lines, but was detectable in the epithelial and stromal cultures of androgen sensitive primary cultures. bFGF was not secreted by cell lines nor epithelial primary cultures. VEGF was universally expressed, but TNF-alpha was not secreted by cells lines nor primary cultures. These data suggest that the expression of angiogenic cytokines by established epithelial CaP cell lines does not reflect epithelial and stromal primary cultures.Prostate Cancer and Prostatic Diseases (2001) 4, 106-111
Prostate Cancer Prostatic Dis 2001
PMID:Differential expression of angiogenic cytokines by cell lines and primary cultures of human prostate cancer. 1249 47


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