Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007097 (carcinoma)
 152,788 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Androgen deprivation therapy (ADT) results in profound morphologic changes in the benign and malignant prostatic epithelium, including acinar shrinkage and distortion, cytoplasmic clearing, and nuclear hyperchromatism. Data on the immunophenotype of prostatic carcinoma following ADT are limited. A-80 is an oncodevelopmental, mucinous glycoprotein that is strongly and consistently upregulated in high-grade prostatic intraepithelial neoplasia and adenocarcinoma; its expression following ADT has not been investigated. We applied a monoclonal antibody to A-80 to paraffin sections of 54 prostatic carcinomas surgically removed after ADT (Leupron with or without flutamide) and found immunoreactions in 53 of 54 samples (98%). Intense staining was seen in cancer glands, solid aggregates, single cells, and mucinous pools as well as in poorly defined acini lined by shrunken and distorted cells that were difficult to identify as malignant. Hemangiopericytoma-like areas showed A-80 staining in the lumina. Normal, metaplastic, hyperplastic, and atrophic ducts were not similarly reactive. Our findings indicate that there is remarkable stability of the upregulated A-80 glycoprotein in prostatic adenocarcinoma after ADT, despite severe architectural and cytologic alterations. The A-80-reactive colloid pools may reflect ruptured neoplastic glands and spillage of secreted material into stromal spaces. Strong A-80 staining, combined with sporadic cytokeratin reactions in the lumina of hemagiopericytomatous areas, suggests that these are souvenirs of carcinomatous glands revealed by antigenic relics of their component cells. The persistence of A-80 immunoreactivity provides a useful marker for recognizing and monitoring prostatic carcinoma after ADT.
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PMID:Stability of the glycoprotein A-80 in prostatic carcinoma subsequent to androgen deprivation therapy. 906 Jun 2

The presence of a tumour significantly changes nitrogen metabolism, including that of amino acids and polyamines, in host animals. In this study, we examine whether developing tumours affect the metabolic relationship of arginine and ornithine, precursors of polyamines, in the testosterone-induced hypertrophic mouse kidney model. Androgen-induced changes in the activity of enzymes involved with ornithine biosynthesis (arginase), its consumption (ornithine aminotransferase, OAT and ornithine decarboxylase, ODC) and the hypertrophy of host mouse kidney were not affected by the presence of an ascitic tumour (EAC) and only slightly by a mammary carcinoma (MaCa). The HPLC determined renal level of arginine and ornithine showed a striking homeostasis and was disturbed neither by testosterone nor EAC. The effect of MaCa and testosterone on the levels of both amino acids, although significant, was not very pronounced. Developing tumours, especially ascitic, altered the renal activity of OAT and ODC, but not of arginase, in testosterone-untreated mice. All examined tumours, EAC, L 1210 and MaCa actively metabolized arginine and ornithine. the tumour content of arginine which coincided with the activity of arginase, resulted in a marked increase of the ornithine/arginine ratio in tumours, when compared with kidneys. These results indicate that the androgen-induced anabolic response in mouse kidney is preserved, in spite of tumour requirements for essential metabolites.
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PMID:Tumour effect on arginine/ornithine metabolic relationship in hypertrophic mouse kidney. 906 93

Bilateral breast tumors, a malignant phyllodes tumor in the right breast and an invasive lobular carcinoma in the left breast, occurred in a 47-year-old woman with 46XX/46XY mosaic karyotype in her peripheral blood lymphocytes and intersex external genitalia. Postmortem examination revealed bilateral ovotestis. Three of the patient's sisters also had breast cancer. In situ hybridization with a Y-specific probe revealed Y-chromosome-specific signal in both tumors, suggesting that the clonal origin of tumors in this patient was Y-containing cells. Androgen-receptor polymorphism also revealed a monoallelic X chromosome pattern in the recurrent phyllodes tumor tissue taken at autopsy, in addition to loss of heterozygosity demonstrated at locus TP53. The slippage of the CA repeats in the tumor was also shown at the loci of D5S82 and D11S527. The mechanistic basis for the occurrence of bilateral malignant tumors of the breast, XX/XY mosaicism, and familial clustering of breast cancer is still unknown. The present study, however, suggests that the sex chromosome abnormality may have modified the cancer phenotype in a manner similar to breast cancer in Klinefelter's syndrome (though phenotypically male) and the Y chromosome may have promoted cell growth.
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PMID:Bilateral breast tumors, malignant phyllodes tumor and invasive lobular carcinoma in a 46,XX/46,XY mosaic female with family history of breast cancer. 908 32

Androgens control cell numbers in the prostate through three separate pathways: (a) inhibition of cell death, (b) induction of cell proliferation (Step-1) and (c) inhibition of cell proliferation (Step-2, proliferative shutoff). The mechanisms underlying these phenomena are incompletely understood. The human prostate carcinoma LNCaP variants express these pathways as follows: LNCaP-FGC express both steps, LNCaP-LNO expresses Step-2, LNCaP-TAC expresses Step-1, and LNCaP-TJA cells express neither step. These cells facilitated the search for mediators of the androgen-induced proliferative shutoff pathway. Androgen exposure for 24 h or longer induced an irreversible proliferative shutoff in LNCaP-FGC cells. The Wang and Brown approach for identifying differentially expressed mRNAs was used to search for mediators of Step-2. Ten unique inserts were identified and from those ten, three genes were further studied. The basal expression of these genes in shutoff-negative variants was not affected by androgen exposure. They were induced by androgens in shutoff-positive LNCaP variants and the androgen receptor-transfected, shutoff-positive, MCF7-AR1 cells. These genes were induced only in the range of androgen concentrations that elicited the shutoff response. Time course analysis showed that their induction precedes the commitment point by 12-18 h. In addition, they were expressed in the normal prostate during proliferative shutoff. These features suggest that the candidate genes have a role in the regulation cascade for proliferative shutoff.
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PMID:Expression of novel genes linked to the androgen-induced, proliferative shutoff in prostate cancer cells. 945 87

Androgen plays a critical role in regulating the growth and differentiation of normal prostate epithelia, as well as the initial growth of prostate cancer cells. Nevertheless, prostate carcinomas eventually become androgen-unresponsive, and the cancer is refractory to hormonal therapy. To gain insight into the mechanism involved in this hormone-refractory phenomenon, we have examined the potential role of the androgen receptor (AR) in that process. We have investigated the expression of AR and two prostate-specific androgen-responsive antigens, prostatic acid phosphatase (PAcP) and prostate-specific antigen (PSA), for the functional activity of AR in LNCaP and PC-3 human prostate carcinoma cells. Our results are as follows. (i) Clone 33 LNCaP cells express AR, PAcP, and PSA, and cell growth is stimulated by 5alpha-dihydrotestosterone (DHT). Stimulation of cell growth correlates with decreased cellular PAcP activity. (ii) In clone 81 LNCaP cells, the expression of PAcP decreases with a concurrent decrease in the degree of androgen stimulation of cell growth, whereas the expression of PSA mRNA level is up-regulated by DHT, as in clone 33 cells. Conversely, in PAcP cDNA-transfected clone 81 cells, an additional expression of cellular PAcP correlates with an increased stimulation by androgen, higher than the corresponding control cells. (iii) PC-3 cells express a low level of functional AR with no detectable PAcP or PSA, and the growth of PC-3 cells is not affected by DHT treatment. Nevertheless, in two PAcP cDNA-transfected PC-3 sublines, the expression of exogenous cellular PAcP correlates with androgen stimulation. This androgen stimulation of cell growth concurs with an increased tyrosine phosphorylation of a phosphoprotein of 185 kDa. In summary, the data indicate that the expression of AR alone is not sufficient for androgen stimulation of cell growth. Furthermore, in AR-expressing prostate cancer cells, the expression of cellular PAcP correlates with androgen stimulation of cell proliferation.
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PMID:Expression of human prostatic acid phosphatase correlates with androgen-stimulated cell proliferation in prostate cancer cell lines. 948 33

Androgen independent prostate cancer is recognized as a chemotherapy resistant disease. Human prostate carcinoma DU-145, LNCaP and PC-3 cells in monolayer in exponential growth were exposed to various concentrations of melphalan, 4-hydroperoxycyclophosphamide or adriamycin for 1 hour. These cells were all responsive to the drugs, with DU-145 cells being the least sensitive and PC-3 cells the most sensitive. When the three human prostate carcinoma cell lines were grown as xenografts in nude or SCID mice and the animals treated with single doses of melphalan, cyclophosphamide or adriamycin, the tumors were not very responsive to the drugs. The DU-145 tumors were highly resistant to each drug. The PC-3 tumors were more sensitive; however, even the PC-3 tumors were less drug responsive than several murine tumors. All three prostate cell lines secreted transforming growth factor-beta (TGF-beta) into the cell culture medium, and when grown as xenograft tumors increased the plasma levels of TGF-beta in the animals. DU-145 cells produced the most TGF-beta and LNCaP cells produced the least. After administration of single doses of each of the chemotherapeutic agents to animals bearing the prostate carcinoma xenografts, there was a time dependent increase in plasma TGF-beta that was greatest in animals bearing the DU-145 tumor and least in animals bearing the LNCaP tumor. Immunohistochemical staining, showed that PC-3 tumors tended to have the most intense staining for TGF-beta and LNCaP tumors the least. In situ hybridization for TGF-beta mRNA showed an increase in TGF-beta mRNA that was time independent after chemotherapy administration in all three tumors. These results support the hypothesis that the drug resistance of prostate carcinoma is manifest in vivo, and that in vivo high levels of TGF-beta may protect these tumors from cytotoxic cancer therapies.
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PMID:Prostate carcinoma response to cytotoxic therapy: in vivo resistance. 950 95

Fibroblast growth factor (FGF) 8, also known as androgen-induced growth factor, was originally isolated from an androgen-dependent mouse mammary Shionogi carcinoma SC-3 cell line, in which it was shown to have androgen-regulated properties. We previously demonstrated that Fgf 8 transcripts were detected in several human prostate and breast cancer cell lines and that recombinant FGF 8 was mitogenic to an androgen-sensitive prostate cancer LNCaP cell line. In this study, to characterize the roles of FGF 8 in clinical hormone-responsive cancers, we established a monoclonal antibody against FGF 8. In Western blots, this antibody specifically interacted with a FGF 8b isoform that was identical between mouse and human but was not identical to other murine 8a and 8c isoforms. In a cell growth assay using SC-3 cells, the newly established anti-FGF 8 antibody blocked androgen- and FGF 8-stimulated growth but not basic FGF-stimulated growth. Immunohistochemical analyses by use of the established anti-FGF 8 antibody demonstrated that FGF 8 was frequently expressed in human prostate cancers, appearing in 40 of 43 cases (93%), whereas both prostatic hyperplasia specimens and normal prostate tissues included in biopsy specimens were negative for FGF 8 expression. On the other hand, FGF 8 was detected in normal ductal and lobular epithelial cells in breast tissues. FGF 8 was also frequently expressed in various breast diseases, including fibroadenomas (5 of 5 cases, 100%), intraductal papillomas (3 of 3 cases, 100%), ductal hyperplasias (3 of 6 cases, 50%), and breast cancers (8 of 12 cases, 67%). Androgen receptors were also immunohistochemically detected in FGF 8-positive prostate cancers (40 of 40 cases, 100%) and FGF 8-positive breast diseases (17 of 19 cases, 89%). These findings strongly suggest that FGF 8 is involved in hormone-related tumorigenesis of the prostate and breast.
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PMID:High frequency of fibroblast growth factor (FGF) 8 expression in clinical prostate cancers and breast tissues, immunohistochemically demonstrated by a newly established neutralizing monoclonal antibody against FGF 8. 960 40

The molecular mechanism of androgen-independent growth of prostate cancer after androgen ablation was explored in LNCaP cells. An androgen-dependent clonal subline of the LNCaP human prostate carcinoma cell line, LNCaP 104-S, progressed to a slow growing stage (104-R1) and then to a faster growing stage (104-R2) during more than 2 yr of continuous culture in the absence of androgen. Androgen-induced proliferation of 104-S cells is inhibited by the antiandrogen Casodex, while proliferation of 104-R1 and 104-R2 cells is unaffected by Casodex. This indicates that proliferation of 104-R1 and 104-R2 cells is not supported by low levels of androgen in the culture medium. Compared with LNCaP 104-S cells, both 104-R1 and 104-R2 cells express higher basal levels of androgen receptor (AR), and proliferation of these two cell lines is paradoxically repressed by androgen. After continuous passage in androgen-containing medium, 104-R1 cells reverted back to an androgen-dependent phenotype. The mechanism of androgenic repression of 104-R1 and 104-R2 sublines was further evaluated by examining the role of critical regulatory factors involved in the control of cell cycle progression. At concentrations that repressed growth, androgen transiently induced the expression of the cyclin-dependent kinase (cdk) inhibitor p21waf1/cip1 in 104-R1 cells, while expression of the cdk inhibitor p27Kip1 was persistently induced by androgen in both 104-R1 and 104-R2 cells. Induced expression of murine p27Kip1 in 104-R2 cells resulted in G1 arrest. Specific immunoprecipitates of Cdk2 but not Cdk4 from androgen-treated 104-R1 cells contained both p21waf1/cip1 and p27Kip1. This observation was confirmed by in vitro assay of histone H1 and Rb (retinoblastoma protein) phosphorylation by the proteins associated with the immune complex. Furthermore, inhibition of Cdk2 activity correlated with the accumulation of p27Kip1 and not p21waf1/cip1. From these results we conclude that androgenic repression of LNCaP 104-R1 and 104-R2 cell proliferation is due to the induction of p27Kip1, which in turn inhibits Cdk2, a factor critical for cell cycle progression and proliferation.
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PMID:Progression of LNCaP prostate tumor cells during androgen deprivation: hormone-independent growth, repression of proliferation by androgen, and role for p27Kip1 in androgen-induced cell cycle arrest. 965 99

Androgen is a mitogen as well as a morphogen for prostatic epithelium. However, the detailed mechanisms of these distinct androgenic actions have not yet been delineated. Therefore, we employed differential display PCR to unveil any potential genes that may be involved in these processes. In this study, we report the isolation and characterization of two alternative splicing forms (p82 and p59) of C9 complementary DNA, the rat homolog of the human deletion of ovarian carcinoma 2 (DOC-2) gene and mouse p96 phosphoprotein, from rat ventral prostate (VP). We found that C9 was up-regulated in rat VP after castration, suggesting that C9 may be regulated by androgen receptor directly or indirectly during prostate degeneration. A similar regulatory pattern was also observed in both the seminal vesicle and dorsolateral prostate, but not in the coagulating gland or other androgen-independent organs. Immunohistochemical analysis of rat VP demonstrated that C9 is detected in the basal epithelia and surrounding stromal cells after prolonged castration. Ribonuclease protection assay and Western blot analysis revealed that p59 is the predominant C9 isoform in rat VP. To unveil the function of C9 in cell growth, we transfected p59 complementary DNA into the C4-2 cells, a derivative of the LNCaP prostatic carcinoma cell line. The p59 stable transfectants exhibited a slower growth rate and an increase in the cell fraction in the G1 phase under our experimental conditions. These data indicate that C9-p59 has growth inhibitory activity for prostatic epithelial cells. Taken together, our results suggest that C9 is up-regulated during prostate degeneration process and may play an active role in the proliferation and differentiation of prostatic epithelium.
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PMID:Regulation of rat DOC-2 gene during castration-induced rat ventral prostate degeneration and its growth inhibitory function in human prostatic carcinoma cells. 968 6

The sequence of events that leads to tumor vessel regression and the functional characteristics of these vessels during hormone-ablation therapy are not known. This is because of the lack of an appropriate animal model and monitoring technology. By using in vivo microscopy and in situ molecular analysis of the androgen-dependent Shionogi carcinoma grown in severe combined immunodeficient mice, we show that castration of these mice leads to tumor regression and a concomitant decrease in vascular endothelial growth factor (VEGF) expression. Androgen withdrawal is known to induce apoptosis in Shionogi tumor cells. Surprisingly, tumor endothelial cells begin to undergo apoptosis before neoplastic cells, and rarefaction of tumor vessels precedes the decrease in tumor size. The regressing vessels begin to exhibit normal phenotype, i.e., lower diameter, tortuosity, vascular permeability, and leukocyte adhesion. Two weeks after castration, a second wave of angiogenesis and tumor growth begins with a concomitant increase in VEGF expression. Because human tumors often relapse following hormone-ablation therapy, our data suggest that these patients may benefit from combined anti-VEGF therapy.
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PMID:Endothelial cell death, angiogenesis, and microvascular function after castration in an androgen-dependent tumor: role of vascular endothelial growth factor. 972 88


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