Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04155 (pS2)
 1,234 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of the major human serum bile acid, glycochenodeoxycholic acid (GCDC), as well as unconjugated chenodeoxycholic acid (CDC), on the MCF-7 human breast cancer cell line have been studied in vitro under oestrogen and bile acid deprived culture conditions. GCDC increased the growth of the breast cancer cells over the range 10-300 microM. At concentrations in excess of the bile acid binding capacity of the medium cell growth was prevented. In contrast 10 microM CDC tended to reduce cell growth. Oestrogen (ER) and progesterone (PgR) receptors, pS2 and total cathepsin D were quantified by monoclonal antibody based immunoassays. Ten to 100 microM GCDC and 10 microM CDC down-regulated ER protein and this was accompanied by induction of the oestrogen-regulated proteins PgR, pS2 and possibly cathepsin D, including increased secretion of the latter two proteins into the culture medium. All these changes were quantitatively similar to those observed with 10 nM oestradiol. The bile acid effects on ER and PgR were not due to interference with the assay procedures. Cells incubated with 50 microM GCDC or 10 microM CDC had higher pmolar concentrations of the bile acids than controls. This study suggests that naturally occurring bile acids influence the growth and steroid receptor function of human breast cancer cells.
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PMID:Bile acids influence the growth, oestrogen receptor and oestrogen-regulated proteins of MCF-7 human breast cancer cells. 156 65

The effects of tamoxifen, three of its in vivo metabolites and 3-hydroxytamoxifen on cellular proliferation and the induction of four oestrogen-regulated RNAs (pNR-1, pNR-2, pNR-25 and cathepsin D) have been measured in MCF-7 breast cancer cells in phenol red-free culture medium. Tamoxifen and 3-hydroxytamoxifen acted as partial oestrogens to stimulate cell growth and the levels of the pNR-2 and pNR-25 RNAs. They were full oestrogens for the induction of cathepsin D RNA and induced the pNR-1 RNA above the level found in oestrogen-treated cells. N-Desmethyltamoxifen and 4-hydroxytamoxifen behaved like tamoxifen except that N-desmethyltamoxifen did not induce the pNR-2 RNA and was only a partial oestrogen for the induction of cathepsin D RNA, and 4-hydroxytamoxifen did not induce the pNR-2 or pNR-25 RNAs. In the presence of oestradiol, the four anti-oestrogens prevented the stimulation of growth and reduced (pNR-2 and pNR-25) or increased (pNR-1) the RNA levels to those present in MCF-7 cells treated with the anti-oestrogen alone. In contrast, for cathepsin D RNA levels there was a synergistic effect of the anti-oestrogens and oestradiol. The concentration at which each anti-oestrogen was effective was related to its affinity for the oestrogen receptor. Metabolite E was a full oestrogen for the induction of cell proliferation and the oestrogen-regulated RNAs. pNR-25 and pNR-2 RNA levels correlated most closely with effects on cell proliferation. These RNAs are therefore potentially the most useful for predicting the response of breast cancer patients to tamoxifen therapy.
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PMID:Oestrogenic activity of tamoxifen and its metabolites on gene regulation and cell proliferation in MCF-7 breast cancer cells. 273 7

The cytosolic levels of pS2, an estrogen-regulated protein, were measured in 100 cases of primary breast cancer and related to several conventional histological and biochemical prognostic factors. The data were statistically analyzed on the basis of two different cutoff point for pS2: 4 and 11 ng/mg of cytosolic proteins. pS2 positivity (cutoff 11 ng/mg) was shown to be associated with small tumor size (p = 0.05), a higher differentiation grade (p = 0.007) and a smaller number of mitoses (p = 0.004), but not with menopausal status, lymph node involvement, cathepsin D levels, or proliferative activity determined by the monoclonal antibody Ki67. With the cutoff of 4 ng/mg, the statistical significance was confirmed only for the number of mitoses (p = 0.03), which was also the most closely related covariate in multivariate analysis (p = 0.008). As regards steroid receptor status, a significant difference was observed between pS2+ and pS2- cases (Chi-square = 8.9; p = 0.04, cutoff 4 ng/mg). in conclusion, pS2 positivity, being preferentially expressed in hormone-dependent cells and related to other well-known positive markers, may either indicate a good prognosis or predict responsiveness to endocrine treatment.
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PMID:Correlation between pS2 protein positivity, steroid receptor status and other prognostic factors in breast cancer. 756 Dec 44

The distribution of PECAM-1/CD31 molecule was investigated in 133 breast carcinomas using monoclonal antibody and frozen sections. Anti-CD31 labels endothelial cells and reflects stromal angiogenesis. The CD31 immunoreactivity was evaluated by computer-assisted analysis of digitized microscopic images. The automatic screening of the whole preparation and the measurements of the mean CD31 immunostained surface was performed in each case. A similar procedure was achieved for p53, cathepsin D, P-gp, pHER-2/neu, Ki67, pS2 estrogen and progesterone antigenic sites immunodetection. The image analysis of positive CD31 surface was variable, ranging from 4% to 33% (mean 14.7%, SD = 5.43). The CD31 positive surface correlated (P < .01) with the Nottingham prognostic index, but not with the tumor size, the node status, the tumor grade, nor with the patient age. Also the CD31 immunoreactivity was independent of the pHER-2/neu, Ki67 antigen, p53, ER, PR and pS2 immunodetectable expression in tumors, but correlates with that of cathepsin D (P = .024) and P-gp (P = .028), which reflects the multi-drug resistance capacity of tumor cells. In conclusion, CD31 positive vessels assessed on frozen sections by image analysis constitute an excellent method of evaluating tumor stromal angiogenesis, and can be further used for clinical purposes. The results also suggest that the CD31/PECAM molecule may be involved in the spread of tumor by interacting with extracellular matrix lysis that results from the tumor cell proteasic activity and with multidrug resistance.
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PMID:CD31 quantitative immunocytochemical assays in breast carcinomas. Correlation with current prognostic factors. 772 41

The effect of structure of the estrogen ligand on the accumulation of tPA mRNA and the activity of extracellular fibrinolytic enzyme has been examined in cultures of MCF-7 cells. Estradiol(E2)-stimulated fibrinolytic activity was preceded by an increase in actinomycin D sensitive tPA mRNA synthesis which peaked at 18 h. Ten A- and D-ring structural analogs of E2 affected tPA mRNA accumulation and extracellular fibrinolytic activity. Only in the case of two A-ring isomers (2- and 4-hydroxyestratrien-17 beta-ol) was the decreased effect of the ligand's structural change on tPA mRNA accumulation and fibrinolysis not explained by a comparable decline in affinity of the ligand for estrogen receptor. Both of these analogs functioned as antiestrogens. The stimulatory capacity of androstanediols on the tPA gene required that the 3-hydroxyl group be positioned in the beta-configuration. Absence of the 17 beta-hydroxy group was beneficial to the maximum accumulation of tPA mRNA. As has been reported for other estrogen responsive genes (progesterone receptor, cathepsin D and pS2), regulation by estrogens is not related directly to the affinity of the ligand for ER, but this activity may be determined by the location of the electronegative isopotential above the A-ring of estrogenic ligands.
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PMID:Induction of tissue plasminogen activator mRNA and activity by structurally altered estrogens. 774 7

The bcl-2 gene encodes a protein which inhibits programmed cell death (apoptosis). This protein was detected by immunohistochemical techniques in 48% of invasive ductal carcinomas of the breast. It was present in well-differentiated carcinomas with hormonal receptors, and proteins synthesized under the control of oestrogens: pS2, cathepsin D and ERD5. In contrast, bcl-2+ carcinomas are less frequently positive for p53 and have a Ki67 score under the mean. bcl-2 protects cells against apoptosis. Accumulation of p53 protein, which is indicative of p53 mutation, would have the same effect; however, these two proteins seem inversely related, an inverse correlation observed by others in breast cancer cell lines and in lymphomas. Tumours positive for bcl-2 escape apoptosis and have worse prognosis but this is not what is found; survival at 5 years, and particularly the absence of recurrence during the first 5 years after surgery, seem to be associated with bcl-2 positivity. The bcl-2 protein seems only to be an important prognostic factor in women over 54 years of age. Moreover, p53-bcl-2+ tumours have a better response to hormonal therapy than p53-bcl-2-tumours.
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PMID:bcl-2 protein in invasive ductal breast carcinomas. 775 87

The pathological and biological features of a consecutive series of impalpable invasive breast carcinoma, detected by mammography in the prevalent round of the breast screening programme, have been compared with a clinically presenting group of carcinomas in age-matched patients. There was a significantly higher prevalence of tubular carcinomas as well-differentiated infiltrating ductal carcinomas in the mammographically detected group, and a lower prevalence of poorly differentiated infiltrating ductal carcinomas. Lymph node metastasis was found in 6.5% of the impalpable group compared with 53% of the clinical group. The prevalence of oestrogen receptor was much higher in the impalpable group (96%) than in the control group (67%), although there were no significant differences for progesterone receptor. The prevalence of pS2 was also much higher in the impalpable group, as was cathepsin D. This finding is surprising in view of the reported relationship between cathepsin D and poorer survival. p53 and c-erb-2 proteins were detectable in fewer impalpable carcinomas. The mean MIBI (Ki-67) index was lower in the impalpable group (11.6) than in the clinical group (15.25). Within the mammographically detected group there was a significant difference in the MIBI index between tubular carcinomas and the different grades of infiltrating ductal carcinomas, with a wide range in each category but no association with size. The impalpable carcinomas detected by mammography differ from clinically presenting carcinomas in many ways, raising the question of whether a proportion or all would progress (dedifferentiate) with time.
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PMID:Pathological and biological features of mammographically detected invasive breast carcinomas. 759 62

A series of 200 breast carcinomas was investigated on frozen sections using PAb 1801 p53 monoclonal antibody and streptavidin biotin peroxidase complex. Densitometric analysis of the immunoprecipitates was assessed by processing digitized microscopic images. p53 was observed in the nucleus of 48% of the tumors. Some tumors (14 of 91) tested in parallel on paraffin sections were negative, although positive on frozen sections. Image analysis showed that the surfaces positive with anti-p53 and the staining intensity were decreased (P < .01) on paraffin sections. The p53 tumor expression was independent of patient age, tumor size, axillary lymph node status, HER-2/neu and cathepsin D expression, and nuclear morphometric parameters. However, p53 correlated with high histological grade (P < .01), lack of estrogen receptor (ER) (P = .0015) and progesterone (PR) (P = .0065) antigenic sites, pS2 detection (P = .03), high Ki-67 immunoreactivity (P = .018), large silver-stained nucleolar organizer region (AgNOR) nuclear surface ratio (P < .02), and degree of hyperploidy (P < .03), and was more often observed in the comedocarcinomas. The results suggest that p53 expression in breast carcinomas is not a totally independent prognostic indicator and that the clinical relevance and prognostic significance of p53 expression in breast carcinomas can be reliably assessed provided that the procedures are standardized, particularly with regard to the use of frozen sections and image analysis processing of the immunodetection.
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PMID:p53 quantitative immunocytochemical analysis in breast carcinomas. 786 46

We have established and characterized a series of variant cell lines in which to identify the critical factors associated with E2-induced malignant progression, and the acquisition to tamoxifen resistance in human breast cancer. Sublines of the hormone-dependent MCF-7 cell line (MCF7/MIII and MCF7/LCC1) form stable, invasive, estrogen independent tumors in the mammary fat pads of ovariectomized athymic nude mice. These cells retain expression of both estrogen (ER) and progesterone receptors (PGR), but retain sensitivity to each of the major structural classes of antiestrogens. The tamoxifen-resistant MCF7/LCC2 cells retain sensitivity to the inhibitory effects of the steroidal antiestrogen ICI 182780. By comparing the parental hormone-dependent and variant hormone-independent cells, we have demonstrated an altered expression of some estrogen regulated genes (PGR, pS2, cathepsin D) in the hormone-independent variants. Other genes remain normally estrogen regulated (ER, laminin receptor, EGF-receptor). These data strongly implicate the altered regulation of a specific subset or network of estrogen regulated genes in the malignant progression of human breast cancer. Some of the primary response genes in this network may exhibit dose-response and induction kinetics similar to pS2, which is constitutively upregulated in the MCF7/MIII, MCF7/LCC1 and MCF7/LCC2 cells.
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PMID:Hormonal carcinogenesis in breast cancer: cellular and molecular studies of malignant progression. 788 Nov 2

We evaluated the prognostic value of tissue polypeptide antigen (TPA), cathepsin D and pS2 in 267 patients operated for primary breast cancer. Cathepsin D, pS2 and cytosol TPA were independent of each other and of N, T, estrogen (ER) and progesterone (PgR) receptors. Cathepsin D was the best prognostic indicator for disease-free survival and pS2 for overall survival. The simultaneous evaluation of the three parameters was an effective discriminator between high and low risk patients in both N- and N+. Considering that cathepsin D, pS2 and cytosol TPA can be easily measured with reliable methods in small amounts of tissue, we conclude that they are a promising panel of biochemical parameters suitable for the assessment of the risk of relapse in patients with breast cancer.
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PMID:Biochemical parameters for prognostic evaluation in patients with breast cancer. 801 Jul 28


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