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)

Cardiovascular complications are a well recognized side-effect of antihormonal therapy in men with prostatic carcinoma. We studied changes in plasma lipoproteins in patients with prostate cancer during treatment with several androgen suppression therapies. Estrogen, orchiectomy, and a combination of LHRH agonist and antiandrogen (flutamide) reduced plasma testosterone concentrations (89-92%) and plasma estradiol decreased by 85%, 44%, and 54%, respectively. Estrogen induced hypertriglyceridemia and elevation of plasma HDL cholesterol, phospholipid, and apolipoprotein A-I and A-II concentrations. Low density lipoprotein (LDL) cholesterol decreased but LDL apolipoprotein B did not. These results suggest that the cardiovascular complications that occur during estrogen administration are not mediated through changes in lipoprotein profile, other than the hypertriglyceridemic effect. Orchiectomy caused hypercholesterolemia and an increase in both total and LDL apolipoprotein B, all of which are strong determinants of cardiovascular disease. The high density lipoprotein (HDL) concentration was not affected despite a reduction in plasma testosterone, perhaps due to a simultaneous decrease in estradiol. Combination therapy had no effect on plasma lipid and apolipoprotein B concentrations, but very low density lipoprotein (VLDL) apolipoprotein B decreased, and LDL apolipoprotein B increased. The HDL cholesterol and apolipoprotein A-I concentrations increased but A-II and phospholipids did not. These results suggest enhanced lipoprotein lipase activity, consistent with the reciprocal changes in VLDL and LDL apolipoprotein B levels, apolipoprotein B enrichment of LDL particles, and increase in HDL cholesterol. The higher apolipoprotein A-I to A-II ratio indicates an increase in HDL2 subfraction due to inhibition of endothelial hepatic lipase, increased secretion of apolipoprotein A-I, or both. These effects are attributed to estradiol, which decreased less than after orchiectomy, and to additional adrenal androgen inhibition by flutamide. We conclude that estradiol plays an important role in determining plasma lipoprotein concentrations in men, and androgens exert an antagonist effect. The lipoprotein profile resulting from the combination treatment is more beneficial than that resulting from orchiectomy or estrogen administration.
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PMID:Changes in plasma lipoproteins during various androgen suppression therapies in men with prostatic carcinoma: effects of orchiectomy, estrogen, and combination treatment with luteinizing hormone-releasing hormone agonist and flutamide. 327 21

Allelic loss studies have been instrumental in identifying tumor suppressor gene loci in a variety of cancers. In this study we analyzed prostate cancer specimens from 52 patients for allelic loss using 8 polymorphic probes for the short arm of chromosome 8. Overall, 32 of 51 (63%) informative tumors showed loss of at least one locus on chromosome 8p. The most frequently deleted region is observed at chromosome 8p22-8p21.2. Loss of one allele is identified in 14 of 23 (61%) tumors at D8S163, in 15 of 32 (47%) tumors at lipoprotein lipase, and in 20 of 29 (69%) tumors at MSR, all on 8p22. Loss of one allele is identified in 16 of 27 (59%) tumors at D8S220 at 8p21.3-8p21.2. In addition to frequent loss of one allele at the MSR locus, one metastatic prostate cancer sample demonstrated homozygous deletion of MSR sequences. Loci telomeric and centromeric to this region are largely retained. A chromosome 8p deletion map is constructed and defines the smallest region of overlap to a 14-cM interval at 8p22 between D8S163 and lipoprotein lipase, flanking the MSR locus. Evidence of chromosome 8q multiplication at locus D8S39 was detected in 5 of 32 (16%) tumors, all of which demonstrated loss with at least one probe on chromosome 8p. This study extends the previous finding of frequent loss of chromosome 8p in prostate cancer by defining a common region of loss of heterozygosity at 8p22 and a homozygous deletion of the MSR locus contained within this region. This is the first homozygous deletion identified in the genome of a human prostate cancer and the highest rate of loss yet reported on chromosome 8p in cancer. These results strongly suggest the presence of a tumor suppressor gene in this region which is frequently inactivated in prostate cancer.
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PMID:Homozygous deletion and frequent allelic loss of chromosome 8p22 loci in human prostate cancer. 768 19

Loss of heterozygosity at chromosome 8p21-22 is common in human prostate cancer, suggesting the presence of one or more tumor suppressor genes at this locus. A homeobox gene that is expressed specifically in adult human prostate, NKX3.1, the expression of which is regulated by androgen, maps to chromosome 8p21. Fine structure in situ mapping showed that NKX3.1 is proximal to MSR32 (macrophage scavenger receptor type II) and LPL (human lipoprotein lipase) and very close to NEFL (human neurofilament light chain) on 8p21. Single-strand conformational polymorphism analysis of 48 radical prostatectomy cancer specimens and 3 metastases for the entire coding region of NKX3.1 showed no tumor-specific sequence alterations in 50 specimens and total absence of the gene in 1 specimen known to have a biallelic deletion of 8p21. NKX3.1 was found to have a polymorphism at nucleotide 154 in codon 52 that resulted in a CGC-->TGC sequence change and an Arg-->Cys amino acid alteration (R52C). This polymorphism was present in 20% of DNA samples. If NKX3.1 is a target of the 8p21 LOH, it is not via disruption of the coding region of the gene.
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PMID:Coding region of NKX3.1, a prostate-specific homeobox gene on 8p21, is not mutated in human prostate cancers. 937 51

PAGE4 is an X chromosome-linked cancer-testis antigen that was identified by expressed sequence tags database mining and a functional genomic approach. PAGE4 is preferentially expressed in normal male and female reproductive tissues and also in a variety of cancers including prostate. In the present study, we have used in situ hybridization to show that PAGE4 mRNA is expressed only in the epithelial cells of normal and prostate-cancer specimens. Analysis of the protein product encoded by the PAGE4 mRNA reveals that it encodes a Mr 16,000 protein and is detected in tissue extracts from both normal prostate and prostate cancer. Cell fractionation analysis of PAGE4 protein indicates that PAGE4 is localized in the cytoplasm of the cell. Furthermore, cDNA microarray analysis indicates that the expression of lipoprotein lipase, a gene frequently deleted in prostate cancer, is down-regulated in a cell line that expresses PAGE4.
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PMID:PAGE4 is a cytoplasmic protein that is expressed in normal prostate and in prostate cancers. 1248 49

A high fat intake has been associated with prostate cancer risk, and gene polymorphisms of lipoprotein lipase (LPL) play an important role in plasma lipoprotein metabolism. We herein analyzed the association of LPL gene polymorphisms with the risk of prostate cancer in a Japanese population. Three single nucleotide polymorphisms (SNPs) of LPL designated as Ser447stop, HindIII and PvuII were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method in 273 prostate cancer patients, 205 benign prostatic hyperplasia (BPH) patients and 230 male controls. The men with the CG + GG genotypes of the Ser447stop polymorphism had an increased risk of prostate cancer compared to those with the CC genotype [age-adjusted odds ratio (aOR) = 1.625; 95% CI = 1.068-2.471; p = 0.023]. Furthermore, the increased risk associated with the CG + GG genotypes was more strongly observed in patients with high-grade cancers (aOR = 2.843; 95% CI = 1.252-6.458; p = 0.039) or metastatic diseases (aOR = 2.300; 95% CI = 1.042-5.074; p = 0.013), whereas the risk was not significant in those with low- to intermediate-grade cancers or nonmetastatic diseases. In the HindIII and PvuII polymorphisms, there was no significant difference between the prostate cancer patients and the controls, and no significant results as for tumor grade and stage. None of the 3 polymorphisms showed any association with the risk of BPH. Our results suggest that the LPL Ser447stop polymorphism is a common genetic modifier for the development of prostate cancer, particularly that of high-grade and/or high-stage, in a Japanese population.
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PMID:Association of lipoprotein lipase gene polymorphism with risk of prostate cancer in a Japanese population. 1538 77

Many types of cancer cells require a supply of fatty acids (FA) for growth and survival, and interrupting de novo FA synthesis in model systems causes potent anticancer effects. We hypothesized that, in addition to synthesis, cancer cells may obtain preformed, diet-derived FA by uptake from the bloodstream. This would require hydrolytic release of FA from triglyceride in circulating lipoprotein particles by the secreted enzyme lipoprotein lipase (LPL), and the expression of CD36, the channel for cellular FA uptake. We find that selected breast cancer and sarcoma cells express and secrete active LPL, and all express CD36. We further show that LPL, in the presence of triglyceride-rich lipoproteins, accelerates the growth of these cells. Providing LPL to prostate cancer cells, which express low levels of the enzyme, did not augment growth, but did prevent the cytotoxic effect of FA synthesis inhibition. Moreover, LPL knockdown inhibited HeLa cell growth. In contrast to the cell lines, immunohistochemical analysis confirmed the presence of LPL and CD36 in the majority of breast, liposarcoma, and prostate tumor tissues examined (n = 181). These findings suggest that, in addition to de novo lipogenesis, cancer cells can use LPL and CD36 to acquire FA from the circulation by lipolysis, and this can fuel their growth. Interfering with dietary fat intake, lipolysis, and/or FA uptake will be necessary to target the requirement of cancer cells for FA.
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PMID:Lipoprotein lipase links dietary fat to solid tumor cell proliferation. 2128 54