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 ability of a cell to modify the extracellular matrix is important in several pathophysiological alterations including tumorigenesis. Cell transformation is accompanied by changes in the surrounding stroma as a result of the action of specific proteases such as the urokinase plasminogen activator (uPA), which has been associated with invasive potential in many tumor types. In this study, we analyzed the release of vesicle-associated uPA by the aggressive prostatic carcinoma cell line PC3 and the implications of this release for the invasive behaviour of prostatic tumor cells. Zymography and Western blot analysis revealed the presence of vesicle-associated uPA in the high-molecular weight form. Vesicles adhered to and degraded both collagen IV and reconstituted basal membrane (Matrigel), and plasminogen enhanced the degradation in a dose-dependent manner. Addition of membrane vesicles shed by PC3 cells to cultures of the poorly invasive prostate cancer cell line LnCaP enhanced the adhesive and invasive capabilities of the latter, suggesting a mechanism involving substrate recognition and degradation. Together, these findings indicate that membrane vesicles can promote tumor invasion and point to the important role of vesicle-associated uPA in the extracellular compartment.
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PMID:Vesicle-associated urokinase plasminogen activator promotes invasion in prostate cancer cell lines. 1123 92

Components of vascular basement membrane are involved in regulating angiogenesis. Recently, tumstatin (the NC1 domain of alpha3 chain of type IV collagen) was identified as possessing anti-angiogenic activity. In the present study, the anti-angiogenic activity of tumstatin was localized to the putative 54-132-amino acid Tum-5 domain, and the activity mediated by alpha(v)beta(3) integrin interaction in an RGD-independent manner. The recombinant Tum-5 produced in Escherichia coli and Pichia Pastoris specifically inhibited proliferation and caused apoptosis of endothelial cells with no significant effect on nonendothelial cells. Tum-5 also inhibited tube formation of endothelial cells on Matrigel and induced G1 endothelial cell cycle arrest. Moreover, anti-angiogenic effect of Tum-5 was also examined in vivo using both a Matrigel plug assay in C57BL/6 mice and human prostate cancer (PC-3) xenografts in nude mice. The in vivo results demonstrate that Tum-5 at 1 mg/kg significantly inhibited growth of PC-3 tumors in association with a decrease in CD31 positive vasculature. These in vivo studies also show that, at molar equivalents, human Tum-5 is at least 10-fold more active than human endostatin. In addition, these studies for the first time suggest that through the action of endogenous inhibitors, alpha(v)beta(3) integrin may also function as a negative regulator of angiogenesis. Taken together, these findings demonstrate that Tum-5, a domain derived from tumstatin, is an effective inhibitor of tumor-associated angiogenesis and a promising candidate for the treatment of cancer.
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PMID:Identification of the anti-angiogenic site within vascular basement membrane-derived tumstatin. 1127 65

Aminopeptidase N (AP-N) degrades collagen type IV and is proposed to play a role in tumor invasion. However, the precise functions of AP-N in tumor cells and the relationship of AP-N to prostate cancer remains unclear. In our study, we examined a possible role for zinc in the regulation of AP-N enzymatic activity in relation to tumor cell invasion in human prostate. AP-N purified from human prostate was irreversibly inhibited by low concentrations of zinc (Ki = 11.2 microM) and bestatin. AP-N, which has zinc in the active center, was also inhibited by the chelating agents, EDTA, o-phenanthroline and EGTA. EDTA was shown to remove zinc from the enzyme. When the effects of zinc and bestatin on invasion of PC-3 cells were investigated in vitro using a Transwell cell-culture chamber, zinc and bestatin effectively suppressed cell invasion into Matrigel at the concentration range of 50-100 microM. These results strongly suggest that the suppression of PC-3 cell invasion by zinc is based on the inhibition of AP-N activity by zinc. We also evaluated the expression of AP-N to investigate the relationship with the progression of prostate disease in human cancerous prostate. AP-N was found to be located at the cytoplasmic membranes of prostate gland epithelial cells and to be expressed more in prostate cancer, while the expression of prostate-specific antigen (PSA), which is a useful marker for prostate cancer, was shown in normal and cancer tissues, suggesting that AP-N is potentially a good histological marker of prostate cancer. Thus, highly expressed AP-N in human cancerous prostate probably plays an important role in the invasion and metastasis of prostate cancer cells.
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PMID:Aminopeptidase N regulated by zinc in human prostate participates in tumor cell invasion. 1127 5

Tumor-stromal interactions have been suggested to be a critical factor in both tumor invasion and tumor metastasis. Here, we examined the role of tumor-stromal interactions using co-cultures of prostate cancer (PC) cells derived from primary and metastatic tumors with primary or immortalized stromal (fibroblast and smooth muscle) cells and their effect on matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) expression. Co-cultures of PC and stromal cells showed enhanced levels of pro-MMP-9 and reduced levels of TIMP-1 and TIMP-2. Whereas enhanced expression of pro-MMP-9 occurred in PC cells, the TIMPs were down-regulated in stromal cells. Induction of pro-MMP-9 and reduction of TIMP expression did not require cell-cell contact and were mediated by a soluble factor(s) present in the conditioned medium of the effector cell. Collagen I is a potent inducer of pro-MMP-9 in PC cells. Consistently, preliminary characterization of the soluble factor in the fibroblast conditioned medium revealed m.w. of approximately 100 to 250 kDa, and its effect on pro-MMP-9 expression was partly inhibited by an anti-alpha2 integrin antibody, a major collagen I receptor. Expression of pro-MMP-9 protein and mRNA was also induced in metastatic PC-3 cells grown in human fetal bone implants in SCID mice. Together, these findings demonstrate the importance of tumor-stromal interactions in the regulation of MMP and TIMP expression and their potential role in PC progression.
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PMID:Differential regulation of matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 expression in co-cultures of prostate cancer and stromal cells. 1147 54

Prostate cancer is the second leading cause of male cancer-related deaths in the United States. Interestingly, prostate cancer preferentially metastasizes to bone. Once in the bone microenvironment, advanced prostate cancer becomes highly resistant to therapeutic modalities. Several factors, such as, extracelluar matrix components, have been implicated in the spread and propagation of prostatic carcinoma. The prostate cell line, PC3, adhere and spread on collagen I to a greater degree than on fibronectin (FN) or poly-L-lysine (PLL). Flow cytometry analysis reveals the presence of the alpha(1), alpha(2) and alpha(3) collagen binding integrin subunits. Antibody function blocking studies reveal that PC3 cells can utilize alpha(2)beta(1) and alpha(3)beta(1) integrins to adhere to collagen I. Cells plated on collagen I exhibit increased rates of proliferation over cells plated on FN or tissue culture plastic. Additionally, cells plated on collagen I show increased expression of cyclin D1, a molecule associated with progression through G1 phase of the cell cycle. Inhibitor studies point to a role for phosphatidylinositol 3-kinase (PI3K), map kinase (MAPK) and p70 S6 kinase in collagen I-mediated PC3 cell proliferation and cyclin D1 expression. Type I collagen may facilitate the colonization and growth of metastatic prostate tumor cells in the bone microenvironment.
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PMID:Type I collagen-mediated proliferation of PC3 prostate carcinoma cell line: implications for enhanced growth in the bone microenvironment. 1169 83

The dietary effect of phytosterols (PS) versus cholesterol on the growth and metastasis of the PC-3 human prostate cancer cells in SCID mice was studied. Also, their direct effect on the growth and migration of these cells in vitro was analysed. In the in vivo experiment, SCID mice were fed a diet containing 2% of either PS mixture or cholesterol plus 0.2% cholic acid and implanted with 2 x 10(6) tumour cells per mouse. Tumour growth was monitored for 8 weeks post inoculation. Animals fed the PS diet had tumours 40-43% smaller than those fed the cholesterol diet. Furthermore, the number of mice with lymph node and lung metastasis was almost one-half that of the cholesterol-fed group. In the in vitro studies, both beta-sitosterol and campesterol inhibited the growth of PC-3 cells by 70% and 14%, respectively, while cholesterol supplementation increased the growth by 18% when compared with controls. PS inhibited the invasion of PC-3 cells into Matrigel-coated membranes by 78% while cholesterol increased it by 43% as compared with the cells in the control media. Migration of tumour cells through 8 microm pore membranes was reduced by 60-93% when the PC-3 cells were in PS media, as compared with a 67% increase after cholesterol supplementation. PS supplementation reduced the binding of PC-3 cells to laminin by 15-38% and fibronectin by 23% while cholesterol increased binding to type IV collagen by 36%. It was concluded that PS indirectly (in vivo as a dietary supplement) and directly (in tissue culture media) inhibited the growth and metastasis of PC-3 cells. beta-Sitosterol was more effective than campesterol in offering this protection in most of the parameters studied.
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PMID:In vitro and in vivo (SCID mice) effects of phytosterols on the growth and dissemination of human prostate cancer PC-3 cells. 1191 49

The diagnostic potential of a new bone resorption marker, type I collagen-cross-linked N telopeptide (NTx), for bone metastasis of prostate cancer was evaluated. Ninty-one prostate cancer patients underwent bone scintigraphy, and urine NTx/creatinine (NTx/Cr) was measured. Urine NTx/Cr levels were compared with bone scintigraphic results. Urine NTx/Cr levels in the bone metastasis-positive group (n = 47) were 92.9 +/- 105.1 nmol/L of bone collagen, which is equivalent to per millimole of urinary creatinine (nmol/L BCE/mmol/L Cr), significantly higher than the level of the bone metastasis-negative group (n = 44) (59.0 +/- 41.6 nmol/L BCE/mmol/L Cr). When patients were classified by the extent of disease grade (EOD grade) nomenclature, the urine NTx/Cr level of the EOD (4+) group was 209.5 +/- 186.5 nmol/L BCE/mmol/L Cr. This level was significantly higher than those of the EOD (-) group (59.0 +/- 41.6 nmol/L BCE/mmol/L Cr), EOD (1+) group (59.0 +/- 47.8 nmol/L BCE/mmol/L Cr), and EOD (2+) group (81.1 +/- 41.3 nmol/L BCE/mmol/L Cr). However, no significant difference was observed between the EOD (-) and EOD (1+) groups. The mean change in urine NTx/Cr level 3 to 17 months after the first bone scintigraphy and urine NTx/Cr examination in the bone metastasis-progression group (n = 8) was 11.0 +/- 31.2 nmol/L BCE/mmol/L Cr, significantly higher than that in the bone metastasis-regression group (n = 15) (-26.8 +/- 40.7 nmol/L BCE/mmol/L Cr). In conclusion, urine NTx /Cr can be measured noninvasively and reflects the state of bone metastasis. However, the sensitivity of urine NTx/Cr is not as high as that of bone scintigraphy. Therefore, it may provide an auxiliary diagnostic index for bone scintigraphy.
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PMID:Correlation of urine type I collagen-cross-linked N telopeptide levels with bone scintigraphic results in prostate cancer patients. 1207 23

Stem cells are believed to regulate normal prostatic homeostasis and to play a role in the etiology of prostate cancer and benign prostatic hyperplasia. We show here that the proximal region of mouse prostatic ducts is enriched in a subpopulation of epithelial cells that exhibit three important attributes of epithelial stem cells: they are slow cycling, possess a high in vitro proliferative potential, and can reconstitute highly branched glandular ductal structures in collagen gels. We propose a model of prostatic homeostasis in which mouse prostatic epithelial stem cells are concentrated in the proximal region of prostatic ducts while the transit-amplifying cells occupy the distal region of the ducts. This model can account for many biological differences between cells of the proximal and distal regions, and has implications for prostatic disease formation.
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PMID:Proximal location of mouse prostate epithelial stem cells: a model of prostatic homeostasis. 1208 83

The metastatic spread of cancer cells involves a complex process of detachment via antiadhesion molecules and attachment and migration through adhesion. In the prostate, androgens are generally thought to contribute to the development and progression of prostate cancer by promoting cell proliferation and survival through poorly defined mechanisms. We have reported previously that PC-3 prostate cancer cells, which are unresponsive to androgens, show androgen-dependent detachment and ultimately apoptosis when stably transfected with a full-length human androgen receptor (AR) cDNA. We now demonstrate that treatment of these cells with 5alpha-dihydrotestosterone (DHT) for 24 or 48 h increased the expression of antiadhesion mucin MUC-1 at the cell surface as detected by flow cytometry with two independent antibodies. This increase in protein was concordant with up-regulation of MUC-1 mRNA in the AR-transfected PC-3 sublines, as determined by quantitative RT-PCR. Treatment with DHT for 48 h also down-regulated the cell surface expression of alpha2beta1-integrin but having little effect on the levels of alpha3beta1- and alpha5beta1-integrins. Androgen also decreased, in a dose-dependent manner, the adhesion of AR-transfected PC-3 cells to collagen type I, which was shown to be specifically inhibited by blocking antibody to alpha2beta1-integrin. The present data demonstrate that DHT can modulate expression of adhesion and antiadhesion molecules and suggest that this effect of androgen might contribute to prostate cancer progression.
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PMID:Androgen modulation of adhesion and antiadhesion molecules in PC-3 prostate cancer cells expressing androgen receptor. 1223 1

In the collagen type I C-telopeptide an aspartyl-glycine site within the sequence AHDGGR is susceptible to molecular rearrangement. In newly synthesized collagen this site is in the native form, denoted alpha L. During aging a spontaneous reaction occurs resulting in three age-modified forms: an isomerized form (beta L) a racemized form (alpha D), and an isomerized/racemized form (beta D). In this study, we measured the urinary excretion of the four forms of C-telopeptides (CTX) in healthy adults and in patients with bone diseases. Levels of all CTX forms were higher in healthy postmenopausal women (P<0.001) compared with premenopausal controls. Levels decreased within 3 days of bisphosphonate treatment indicating that all CTX forms reflect bone resorption. In hyperthyroidism, characterized by a generalized increased bone turnover, native (alpha L) and age-modified (beta L, alpha D and beta D) forms increased to a similar extent compared to controls, resulting in normal ratios between the alpha L and age-modified forms of CTX. Conversely, in Paget's disease and prostate cancer-induced bone metastases, conditions characterized by focal increased bone turnover, alpha L CTX levels were more elevated than those of age-related CTX forms, resulting in increased ratios between native and age-modified CTX. For example, the ratio alpha L/alpha D was increased 7-fold in Paget's disease (P<0.001) and 2-fold in prostate cancer-induced bone metastases (P<0.002). In conclusion, the study suggests that in conditions with a localized alteration in bone turnover the ratio between alpha L CTX and the age-modified forms is significantly elevated. This may provide a new diagnostic and monitoring tool for diseases such as metastatic bone cancer and Paget's disease.
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PMID:Investigation of bone disease using isomerized and racemized fragments of type I collagen. 1238 13


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