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)

Benign and malignant prostatic tissue was removed in surgery and partitioned for (a) ultrastructural study, (b) tissue culture, and (c) (c) immunochemical study. Fourteen malignant and 18 benign prostatic cancer specimens were examined by transmission electron microscopy (TEM) for the presence of viruses or virus-like particles. Viruses could not be identified with assurity in thin sections. Acinar cells of normal, benign prostatic hypertrophy (BPH), and neoplastic prostate tissue were examined in the scanning electron microscope and TEM and found to be extremely heterogenous in their surface morphologies. Three major types of surface morphologies were present: microvillous, ruffled, and bare. All three types of cells were present in normal, BPH, and neoplastic acini. A collagenase procedure was utilized to remove the stromal cells from glandular structures prior to in vitro cultivation. Partially purified extracts from 71 human urothelial tumors and 75 human urothelial nontumor tissues were used as competing antigens in competition radioimmunoassay in an effort to detect the presence of one of the structural components of type-C ribonucleic acid viruses, the p30 core protein. The urothelial tumors tested included 42 BPH specimens and 18 prostatic carcinoma specimens. Thirty-eight percent of the prostatic carcinoma tissues and 48% of the BPH tissues demonstrated the presence of a protein antigenically similar to the p30 core protein of an oncogenic RNA virus.
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PMID:Morphologic and immunologic studies of human prostatic carcinoma. 6 19

Urogenital tissue specimens were maintained in culture for 2 years. Epithelioid growth was enhanced with use of collagenase digestion rather than trypsinization. Twenty of 34 prostate cancer cell cultures survived more than ten in vitro passages, during which time four of 20 demonstrated epithelioid morphology. One epithelioid line (T-157) survived 32 in vitro passages. The cells demonstrated lack of contact inhibition in culture, were slightly positive in acid phosphatase tests, and reacted positively with cytomegalovirus (CMV)-immune sera in indirect immunofluorescence (IF) tests. These cells, which were proven to be of human male origin, failed to yield infectious virus and could be re-isolated from a nodule induced by the cells when injected sc into weanling athymic nude mice. The serum of the patient from which the tumor cells were derived demonstrated high CMV antibody titers and reacted with the virus-specific membrane and intracellular antigens of CMV-transformed human cells in IF tests. A CMV strain isolated from one of the normal prostate cell cultures established an in vitro long-term persistent infection of human embryo lung cells which resulted in the development of two transformed cell lines. The transformed cells possessed CMV antigenic markers and induced non-differentiated tumors when transplanted into athymic nude mice. The results constitute further evidence of the transforming capacity of CMV, and suggest that the virus may be oncogenic in its natural (human) host.
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PMID:Cytomegalovirus and cancer of the prostate: in vitro transformation of human cells. 6 20

To evaluate the role of small amounts of DHT in prostate tissue as a stimulus to epithelial cell growth (protein synthesis) we studied tissue from patients given various androgen-blocking drugs prior to transurethral resection of the prostate (TURP) and measured epithelial protein synthesis and DHT in the tissue specimens. We also studied the effects on stromal cell protein synthesis of an antiestrogen, tamoxifen. Test drugs prior to TURP included Megace 160 mg per day, Megace 160 mg per day plus Tamoxifen 40 mg per day, Megace 160 mg a day plus ketoconazole 1200 mg per day and tamoxifen 40 mg/day. The tissue was processed immediately and epithelial and stromal cells separated by digestion of tissue with 0.5% collagenase. After separation, epithelial cells were labeled with either [3H]leucine or L-[35S]methionine. Stromal cells were labelled with [3H]proline. DHT was measured in whole prostate tissue. Megace alone and Megace plus tamoxifen significantly decreased both [3H]leucine incorporation into protein and tissue concentration of DHT; Megace plus ketoconazole significantly decreased L-[35S]methionine incorporation into protein and DHT. Tamoxifen significantly decreased stromal protein synthesis. When the data correlating DHT with epithelial protein synthesis using both labeling techniques were combined, the curves were parallel and a strong correlation was noted between DHT and protein synthesis over a wide range of values (P less than 0.001). These results suggest that in hormone-dependent prostate cancer even small amounts of prostate DHT such as may occur from adrenal androgens following castration may significantly stimulate growth of the tumor epithelial cells. Since tamoxifen decreased stromal protein synthesis, estrogen is likely a significant growth stimulus to the increased stromal mass characteristic of benign prostatic hypertrophy.
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PMID:Effect of antiandrogen and/or antiestrogen blockade on human prostate epithelial and stromal cell protein synthesis. 243 6

A nuclear binding (NB) assay has been developed for the measurement in intact viable cells of biologically active (functional) estrogen and progesterone receptors, i.e. those capable of binding to nuclear acceptor sites [Spelsberg et al., Endocrinology 121: 631 (1987)]. This paper describes the application of this assay to analyses of androgen receptors in the guinea pig seminal vesicle and in human prostatic carcinoma. Cells from fresh animal seminal vesicles or human prostate carcinoma are isolated using collagenase and are incubated with [3H]R1881 for 1 h at 22 degrees C, after which nuclei are isolated at 4 degrees C and assayed for DNA and radioactivity. This NB assay demonstrates a saturable, temperature dependent, steroid and tissue specific nuclear binding of [3H]R1881 for the guinea pig-seminal vesicle system. The nuclear binding is of high affinity and low capacity. The NB assay reveals several important aspects of the androgen and estrogen receptors in target tissues: (1) the nuclear acceptor sites for androgen receptor (AR) are steroid receptor specific; (2) there are different concentrations of the androgen and estrogen receptors between the epithelium and the fibromuscular components of the guinea pig seminal vesicle; and finally (3) some biopsies of human prostate cancer appear to contain biologically inactive AR. This assay may be useful in the analyses of functional receptors in biopsies of human cancer cells.
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PMID:A nuclear binding assay for measurement of biologically active androgen receptors in animal tissues and human prostate cancer. 326 Sep 78

To evaluate the role of small amounts of prostatic tissue dihydrotestosterone (DHT) as a stimulus to epithelial cell protein synthesis, we studied tissue from 27 patients given various androgen-blocking drugs for 1 week before transurethral resection of the prostate (TURP) and measured epithelial protein synthesis and DHT levels in the tissue specimens. Test drugs before TURP included megestrol acetate 160 mg per day, with and without Tamoxifen 40 mg per day, or ketoconazole 1200 mg per day. The tissue was processed immediately and epithelial cells separated by digestion of tissue with 0.5% collagenase. After separation, epithelial cells were labelled with either 3H-leucine or L-35S-methionine. The DHT level was measured in whole prostatic tissue. Megestrol acetate alone and with tamoxifen significantly decreased both the incorporation of 3H-leucine into protein and the tissue concentration of DHT; megestrol acetate plus ketoconazole significantly decreased L-35S-methionine incorporation into protein and the DHT level. When the data correlating DHT with protein synthesis using both labelling techniques were combined, the curves were parallel and a strong correlation was noted between DHT and protein synthesis over a wide range of values (P less than 0.001). These results suggest that in hormone-dependent prostatic cancer even small amounts of prostatic DHT such as may occur from adrenal androgens following castration may significantly stimulate protein synthesis of the tumour epithelial cells.
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PMID:Relationship between human prostatic epithelial cell protein synthesis and tissue dihydrotestosterone level. 366 14

Prostatic secretory and basal or stem cells were isolated from rat ventral prostate lobes by collagenase dispersion and density centrifugation in a Percoll gradient. The membrane-bound adenylyl cyclase of secretory cells could be activated in a dose-dependent manner by vasoactive intestinal peptide (VIP ED50 10(-7)M) but not thyrotropin-releasing hormone (TRH). Conversely, only TRH could significantly stimulate the adenylyl cyclase in basal cell membranes (ED50 5 X 10(-7). In two separate studies enzyme activity was stimulated seven- and 13-fold by this peptide. This action of TRH on prostatic basal cells supports previous reports that high levels of immunologically active TRH have been found in prostate tissue and that TRH stimulates the growth of prostatic cancer cells in vitro.
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PMID:Thyrotropin-releasing hormone (TRH) activates the adenylyl cyclase of nonsecretory cells in the rat ventral prostate. 643 3

At present, there is no established diagnostic method by which the metastatic ability of an individual prostatic cancer can be accurately predicted. Metastasis is a multistep process, the first critical step of which is invasion. Tumor invasion has been suggested to involve a variety of hydrolytic enzyme activities; therefore, the tumor levels of these activities might be indicative of the overall metastatic ability of the cancer. In order to evaluate if the quantitative levels of hydrolytic enzymes can be used to predict the metastatic ability of individual prostatic cancers, five different Dunning R-3327 rat prostatic adenocarcinoma sublines, with widely varying metastatic abilities, were assayed for the respective levels of a variety of hydrolytic enzyme activities (collagenase, trypsin-like, cathepsin B, neutral protease, N-acetyl-beta-glucosaminidase, chymotrypsin-like, leucine aminopeptidase, elastase, and plasminogen activator). These studies demonstrated that most hydrolytic activities are not elevated when going from normal prostate to prostatic cancer. In addition, only the levels of elastase and chymotrypsin-like activity were found to be consistently higher in highly metastatic prostatic cancers than in either the normal prostate or low-metastatic prostatic cancers. It was found that, by combining the relative activities of elastase and chymotrypsin-like activity and then dividing by the relative activities of N-acetyl-beta-glucosaminidase, a biochemical metastatic index could be constructed which accurately reflected the respective metastatic ability of the Dunning sublines.
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PMID:Biochemical methods for predicting metastatic ability of prostatic cancer utilizing the dunning R-3327 rat prostatic adenocarcinoma system as a model. 653 99

Death from cancer results from the development of metastases or local progression of tumour. Metastasis and local progression may result from the inappropriate activity of metalloproteinases released by tumour cells or of their regulatory peptides. We have developed quantitative assays for interstitial collagenase, stromelysin 1 and tissue inhibitors of metalloproteinase (TIMP) 1 and 2, which have allowed the study of serum levels of these proteins. Sera from 40 patients with prostatic cancer, stored prior to and after 6 and 12 months' treatment with a gonadotrophin-releasing hormone agonist and an anti-androgen were analysed. Levels were compared with two control groups, comprising 21 patients with active rheumatoid arthritis and 56 age-matched hospital attenders without arthritis or cancer. Contrasting levels have been found in patients with prostatic cancer as compared with hospital controls without cancer and patients with rheumatoid arthritis. Patients with prostatic cancer had higher levels of TIMP-1 and collagenase (P = 0.0001) and lower levels of TIMP-2 (P = 0.003) than controls. Patients with metastatic cancer had significantly higher levels of collagenase than those without metastases (P = 0.02). Patients with rheumatoid arthritis had significantly higher levels of stromelysin than either controls (P = 0.002) or patients with cancer (P = 0.008). Serum tissue inhibitor of metalloproteinase 1 in combination with collagenase levels was as sensitive as prostate-specific antigen as a marker of metastatic disease. These findings provide a basis for the investigation of the role of metalloproteinases and their inhibitors in other malignancies.
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PMID:Serum metalloproteinases and their inhibitors: markers for malignant potential. 808 Jul 38

We have previously shown that a 78-kDa "invasion stimulating factor" (ISF) triggers collagenase IV (MMP-2) secretion and the invasive behavior of metastatic PC-3 ML subclones in modified Boyden chamber assays [Stearns, M. E.; Stearns, M. Autocrine factors, type IV collagenase secretion and prostatic cancer cell invasion. Cancer Metastasis Rev. 12:39-52; 1993. Wang, M.; Stearns, M.; Stearns, M. E. Identification of the receptor for a novel M(r) 78,000 "invasion stimulating factor" from metastatic human prostatic PC-3 ML clones. Cancer Res. 54:2492-2495; 1994.]. Recently, we have shown that interleukin 10 (IL-10) preferentially stimulates tissue inhibitor of metalloproteinase-1 (TIMP-1) production in these cells [Wang, M.; Stearns, M. E. Characterization of a novel TIMP-1 enhancer element. J. Biol. Chem., submitted.]. In this paper, we report that IL-10 (20-40 ng) can inhibit the invasion stimulatory effects of ISF (30-60 ng) on PC-3 ML cells. "Checkerboard analysis" with modified Boyden chambers (precoated with 10 and 100 micrograms collagen IV) shows that IL-10 inhibits the stimulatory effects of ISF on both cell motility and chemoinvasion processes. In support of these data, exogenously supplied TIMP-1 (10 micrograms/ml) and collagenase antibodies (1:200 dilution) both completely blocked invasion. Quantitative ELISAs comparing the molar ratios of TIMP-1:MMP-2 and TIMP-2:MMP-2 further demonstrate that IL-10 (10-40 ng) preferentially activates TIMP-1 secretion to increase the molar ratio of TIMP-1:MMP-2 in the presence of increasing amounts of ISF (0-60 ng). IL-10 did not elevate TIMP-2 secretion or influence the molar ratio of TIMP-2:MMP-2.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:IL-10 blocks collagen IV invasion by "invasion stimulating factor" activated PC-3 ML cells: upregulation of TIMP-1 expression. 855 49

Tumor progression to the stage of metastasis may result in part from the selection of certain primary tumor cell clones which are phenotypically competent for survival, invasion, and growth at secondary sites. Selection for traits such as loss of growth inhibitory responses, acquisition of increased adhesiveness, increased local immunosuppression, and enhanced motility and collagenase activities likely contribute to cancer progression and may be regulated through the action of growth factors. The transforming growth factors (TGF-beta) family of growth factors has often been associated with these traits and tumor progression; therefore, elimination or subversion of TGF-beta-responsive pathways should be considered as a mechanistic framework for metastatic events. In this report, we have compared growth and extracellular matrix responses to TGF-beta in six metastatic and six primary tumor-derived cell lines in a mouse model of prostate cancer. We have found that tumor cell lines derived from focal pulmonary metastasis secreted relatively greater quantities of total TGF-betas, lost most or all TGF-beta1 growth inhibition, but responded to TGF-beta1 through induction of the type IV collagenase matrix metalloproteinase-9, whereas cell lines derived from tumors which proliferated at the primary site retained the growth inhibition but lacked collagenase activity. Synthesis of another extracellular matrix protein, plasminogen activator inhibitor 1, was stimulated by TGF-beta1 in both primary as well as metastatic tumors. These results suggest that acquisition of differential responses to the TGF-beta family could result in phenotypic traits which facilitate tumor metastasis from certain primary site clones.
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PMID:Transforming growth factor beta1 stimulates contrasting responses in metastatic versus primary mouse prostate cancer-derived cell lines in vitro. 876 34


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