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)

Our findings demonstrate the presence of VDR in various human prostate cancer cell lines and in primary cultures derived from normal, BPH and prostate cancer. In addition, 1,25-D induced several bioresponses in these cells including growth inhibition and PSA stimulation. Based on examples in many different malignant cells as well as our data in prostate cells, that vitamin D is anti-proliferative and promotes cellular maturation, it seem clear that vitamin D must be viewed as an important cellular modulator of growth and differentiation if addition to its classical role as regulator of calcium homeostasis. In this respect, vitamin D has the potential to have beneficial actions on various malignancies including prostate cancer. Its ultimate role in prostate cancer remains to be determined, but 1,25-D may prove useful in chemoprevention and/or differentiation therapy. We believe the data currently available provide the basis for an optimistic view on the possible use of vitamin D to treat prostate cancer in patients and that further investigation is clearly warranted to better define its potential therapeutic utility.
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PMID:Vitamin D and prostate cancer. 764 28

It has been suggested that vitamin D deficiency may promote prostate cancer, although the mechanism is not understood. In this study three human prostate carcinoma cell lines, LNCaP, DU-145, and PC-3, were examined both for the presence of specific 1,25 dihydroxyvitamin D3 [1,25(OH)2D3] receptors (VDRs) and also employed to study the effects of hormone on cell proliferation and differentiation. Ligand binding experiments demonstrated classical VDR in all three cell lines examined with an apparent dissociation constant of 7.5, 5.4, and 6.3 x 10(-11) M for LNCaP, DU-145, and PC-3 cells, respectively. Corresponding binding capacity for the three prostate carcinoma cell lines were 27, 31, and 78 fmol/mg protein, respectively. The presence of VDR in the three cell lines was also confirmed by immunocytochemistry. In addition, one major 4.6-kilobase messenger RNA transcript hybridizing with a specific human VDR complementary DNA probe was identified in all three cell lines. Interestingly, both DU-145 and PC-3 but not LNCaP cell lines exhibited 1,25(OH)2D3-stimulated induction of 24-hydroxylase messenger RNA employed as a marker of 1,25(OH)2D3 action. Physiological levels of 1,25(OH)2D3 dramatically inhibited proliferation of the LNCaP and PC-3 cell lines. However, in spite of the presence of high affinity VDR, proliferation of DU-145 cells was not inhibited by 1,25(OH)2D3 at the doses tested. Treatment with 1,25(OH)2D3 caused a dose-dependent stimulation of prostate-specific antigen secretion by LNCaP cells. In conclusion, these results demonstrate that these three human prostate carcinoma cell lines all possess specific VDR and that 1,25(OH)2D3 treatment can elicit both an antiproliferative and a differentiating action on these cancer cells. The findings lend support to the hypothesis that vitamin D might exert beneficial actions on prostate cancer risk.
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PMID:Vitamin D and prostate cancer: 1,25 dihydroxyvitamin D3 receptors and actions in human prostate cancer cell lines. 768 37

The active metabolite of vitamin D, 1,25 (OH)2D3, exerts its cell cycle regulating effects via binding to VDR (Vitamin D Receptor). This complex forms a heterodimer with RXR (Retinoic X Receptor). The VDR-RXR heterodimer binds to promoter regions of cell cycle regulating genes through a vitamin D response element (VDRE). The tumour suppressor gene cyclin kinase inhibitor (Cki) p21, one of the well known cell cycle regulating genes, is one of the genes regulated in this manner. Its tumour suppressive action is through inhibition of cell division. These molecular biological mechanisms and large epidemiological investigations give strong support for the benefits of vitamin D in preventing colon cancer and prostate cancer.
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PMID:[Molecular effects of vitamin D on cell cycle and oncogenesis]. 969 32

Prostate cancer is a major cause of male cancer death. In vitro and in vivo data support a role for 1 alpha,25 Dihydroxyvitamin D(3) (1 alpha,25(OH)(2)D(3)) in regulating the growth and differentiation of the normal prostate gland yet prostate cancer cells appear significantly less sensitive to this action. Vitamin D(3) receptor (VDR) content or mutational status do not correlate clearly with the antiproliferative effects of 1 alpha,25(OH)(2)D(3) and therefore it is unclear why prostate cancer cell lines are significantly less sensitive to this action. We hypothesized that the antiproliferative responses of prostate cancer cells to 1 alpha,25(OH)(2)D(3) are suppressed by a process involving histone deacetylation. Sodium butyrate (NaB) and trichostatin A (TSA) are inhibitors of histone deacetylase (HDAC) activity. Low doses of NaB or TSA (300 microM and 15 nM respectively), which alone were relatively inactive, synergized with 1 alpha,25(OH)(2)D(3) in liquid and semi-solid agar to inhibit the growth of LNCaP, PC-3 and DU-145 prostate cancer cells. Still greater synergy was observed between vitamin D(3) hexafluoride analogs and either NaB or TSA. The mechanism appeared to involve neither the cyclin-dependent kinase inhibitor, p21((waf1/cip1)) nor cell cycle arrest, but rather induction of apoptosis. These data suggest that cells dysregulate the normal pro-apoptotic signals of 1 alpha,25(OH)(2)D(3) during prostate cancer development by a mechanism involving histone deacetylation. Combination therapy with potent vitamin D(3) analogs and clinically approved HDAC inhibitors may overcome this lesion and improve the treatment of both androgen-dependent and independent prostate cancer.
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PMID:Synergistic growth inhibition of prostate cancer cells by 1 alpha,25 Dihydroxyvitamin D(3) and its 19-nor-hexafluoride analogs in combination with either sodium butyrate or trichostatin A. 1131 34

Epidemiological studies have suggested that UV exerts a protective effect on prostate cancer. Accordingly, we determined, in 210 prostate cancer cases, whether parameters of exposure, skin type and polymorphism in MC1R, VDR and TYR were associated with the outcome parameters, histological grade, clinical stage and presence of bone metastases. We used logistic regression analysis, with correction for age and metastases, stage and grade in the models, to determine if the frequencies of individual factors were different in the patient groups. The development of metastases was not associated with UV exposure parameters. Paradoxically, patients with skin type 1 were at significantly reduced risk [P = 0.027, odds ratio (OR) 0.17, 95% CI 0.03-0.82] of developing metastases compared with cases with skin type 4. MC1R Val92/Val92 and VDR ff were associated with increased risk of metastases (ORs 4.30 and 4.98, respectively). Further, cumulative exposure (P = 0.005, OR 0.85/year) and increasing proportion of outdoor occupation (P = 0.001, OR 0.84/unit) were associated with reduced risk of advanced stage tumours. Skin types, MC1R or VDR genotypes were not significantly associated with advanced stage. None of the exposure parameters, skin types or genotypes were associated with tumour grade. While MC1R Val92/Val92 and VDR ff were only associated with bone metastases, TYR genotypes were associated with each of the outcome parameters. Thus, in logistic regression models that included age, but not advanced stage and high grade histology, TYR A1A2 was significantly associated with reduced risk of metastases (P = 0.033, OR 0.41). Similarly, in models that included age but not the other outcome parameters, associations between TYR A2A2 and high-grade and advanced stage were significant (P = 0.040, OR 0.41) or approached significance (P = 0.052, OR 0.44), respectively. These data indicate for the first time that pigmentation response to UV is associated with outcome in prostate cancer.
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PMID:Outcome in prostate cancer associations with skin type and polymorphism in pigmentation-related genes. 1153 53

Prostate cancer is a complex, multifactorial disease with genetic and environmental factors involved in its etiology. The search for genetic determinants involved in the disease has proven to be challenging, in part because such complex diseases are often not amenable to characterization by linkage analysis and positional cloning as is the case for diseases with simple Mendelian genetic inheritance. Prostate cancer susceptibility loci that have been reported so far include HPC1 (1q24-q25), PCAP (1q42-q43), HPCX (Xq27-q28), CAPB (1p36), HPC20 (20q13), HPC2/ELAC2 (17p11) and 16q23. Prostate cancer aggressiveness loci have also been reported (5q31-q33, 7q32 and 19q12). Further complicating the process is the existence of polymorphisms in several genes associated with prostate cancer including, AR, PSA, SRD5A2, VDR and CYP isoforms. These polymorphisms, however, are not thought to be highly penetrant alleles in families at high risk for prostate cancer. It is clear that prostate cancer etiology involves several genetic loci with no major gene accounting for a large proportion of susceptibility to the disease.
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PMID:Heterogeneity of genetic alterations in prostate cancer: evidence of the complex nature of the disease. 1167 16

Exposure to ultraviolet radiation may reduce prostate cancer risk, suggesting that polymorphism in genes that mediate host pigmentation will be associated with susceptibility to this cancer. We studied 210 prostate cancer cases and 155 controls to determine whether vitamin D receptor (VDR, Taql and Fokl variants), tyrosinase (TYR, codon 192 variant) and melanocortin-1 receptor (MC1R, Arg151Cys, Arg160Trp, Val92Met, Asp294His and Asp84Glu variants) genotypes are associated with risk. UV exposure was determined using a questionnaire. MC1R Arg(160)/Arg(160) homozygotes were at increased risk (P = 0.027, odds ratio = 1.94) while TYR A2/A2 homozygotes were at reduced risk of prostate cancer (P = 0.033, odds ratio = 0.48). These associations remained significant after correction for UV-exposure. Stratification of cases and controls by quartiles of exposure, showed that the protective effect of TYR A1A2 (P = 0.006, odds ratio 0.075) and A2A2 (P = 0.003, odds ratio 0.055) was particularly strong in subjects who had received the greatest exposure. Our data show for the first time, that allelism in genes linked with skin pigment synthesis is associated with prostate cancer risk possibly because it mediates the protective effects of UV. Importantly, susceptibility is associated with an interaction between host predisposition and exposure.
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PMID:Prostate cancer risk: associations with ultraviolet radiation, tyrosinase and melanocortin-1 receptor genotypes. 1172 Apr 36

Although many studies have examined the mechanisms of 1,25-dihydroxyvitamin D(3) (calcitriol or 1,25 D) action in different prostate cancer cell lines, little is known regarding the influence of this steroid on the normal prostate. The presence of both VDR and AR in normal prostatic tissues raises the distinct possibility of an important role for this hormone in the normal gland. In order to ascertain the possible role of 1,25 D on both AR and VDR in the normal prostate, the effects of calcitriol and dihydrotestosterone (DHT) on the normal human neonatal prostatic epithelial cell line, 267B-1, were examined. These studies were approached by focusing on how 1,25 D in the presence or absence of DHT affects the distribution of AR and VDR in the cytoplasmic and nuclear compartments of the cells in terms of their protein levels and DNA binding activities. Immunoblot analyses show that 1,25 D increases the AR protein level in both the cytoplasmic and nuclear fractions but not the VDR protein level. On the other hand, the gel shift assays demonstrate that 1,25 D increases both the AR- and VDR-DNA binding activities in the nuclear fraction, whereas there is no increase in DNA binding activities in the cytoplasmic fraction. Addition of DHT along with 1,25 D does not affect the DNA binding activities of both AR and VDR. Overall, these studies suggest that 1,25 D actions on the normal prostate cells may be mediated independently through AR and VDR, respectively.
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PMID:Effects of 1,25-dihydroxyvitamin D3 on the distribution of androgen and vitamin D receptors in human prostate neonatal epithelial cells. 1253 36

In this report we describe that 1,25(OH)(2)D(3)-3-BE, a VDR-affinity labeling analog of 1,25(OH)(2)D(3), showed strong and dose-dependent growth-inhibitory effect in several epithelial cells, i.e., keratinocytes (primary cells), MCF-7 breast cancer, PC-3, and LNCaP prostate cancer and PZ-HPV-7 immortalized normal prostate cell-lines. Furthermore, 10(-6) M of 1,25(OH)(2)D(3)-3-BE induced apoptosis specifically in LNCaP and PC-3 cells; and the effect was much less pronounced at lower doses. We also showed that the effect (of 1,25(OH)(2)D(3)-3-BE) was not due to probable degradation (hydrolysis) of 1,25(OH)(2)D(3)-3-BE or random interaction of this molecule with cellular proteins. Tissue- or cell-specific action of 1,25(OH)(2)D(3) and its mimics is not common due to the ubiquitous nature of VDR. Furthermore, variable effects of 1,25(OH)(2)D(3) and its analogs in various cell-lines potentially limits their application as anticancer agents. We showed that 1,25(OH)(2)D(3)-3-BE displayed similar growth-inhibitory and cytotoxic activities towards androgen sensitive LNCaP and androgen-independent PC-3 cell-lines. Therefore, these results raise the possibility that 1,25(OH)(2)D(3)-3-BE or similar VDR-cross linking analogs of 1,25(OH)(2)D(3) might be considered for further development as potential candidates for prostate cancer.
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PMID:1alpha,25-Dihydroxyvitamin D3-3beta-(2)-bromoacetate, an affinity labeling derivative of 1alpha,25-dihydroxyvitamin D3 displays strong antiproliferative and cytotoxic behavior in prostate cancer cells. 1287 25

Prostate cancer (PCa) cells harbor receptors for vitamin D (VDR) as well as androgens (AR). 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] increases AR expression and enhances androgen actions linking the two receptor systems. 1,25(OH)2D3 exhibits antiproliferative activity in both AR-positive and AR-negative PCa cells. Less calcemic analogs of 1,25(OH)2D3, with more antiproliferative activity, are being developed and will be more useful clinically. The mechanisms underlying differential analog activity are being investigated. In target cells, 1,25(OH)2D3 induces 24-hydroxylase, the enzyme that catalyzes its self-inactivation. Co-treatment with 24-hydroxylase inhibitors enhances the antiproliferative activity of calcitriol. Primary cultures of normal or cancer-derived prostatic epithelial cells express 1alpha-hydroxylase, the enzyme that catalyzes the synthesis of 1,25(OH)2D3, the levels being much lower in the cancer-derived cells and in PCa cell lines. This finding raises the possibility of using 25-hydroxyvitamin D3 [25(OH)D3] as a chemopreventive agent in PCa. In LNCaP human PCa cells, 1,25(OH)2D3 and its analogs exert antiproliferative activity predominantly by cell cycle arrest, but also induce apoptosis, although to a much lesser degree. Growth arrest is mediated by induction of IGF binding protein-3 (IGFBP-3), which in turn increases the expression of the cell cycle inhibitor p21, leading to growth arrest. Other actions of 1,25(OH)2D3 in PCa cells include promotion of pro-differentiation effects and inhibition of tumor cell invasion, metastasis and angiogenesis. Combination therapy with retinoids, other anticancer agents or 24-hydroxylase inhibitors augments the inhibitory activity of 1,25(OH)2D3 in PCa and provides another effective approach in PCa treatment. Small clinical trials have shown that 1,25(OH)2D3 can slow the rate of prostate specific antigen (PSA) rise in PCa patients, demonstrating proof of concept that 1,25(OH)2D3 or its analogs will be clinically effective in PCa therapy. Current research involves further investigation of the role of 1,25(OH)2D3 and its analogs for the therapy or chemoprevention of PCa.
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PMID:The role of vitamin D in prostate cancer. 1289 24


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