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)

Quantitative imaging of estrogen receptors (ER's), progesterone receptors (PR's), estrogen-regulated protein (pS2), and growth fraction (Ki67) immunocytochemical assays were performed in 52 meningiomas. The results were correlated with clinical (age, sex, hormonal status, and tumor volume and location) and morphological (histological types and grades) data. The authors observed a lack of ER's in all meningiomas but the presence of PR's in 53% of these meningiomas. The immunoreactivity was restricted to tumor cell nuclei. The PR immunocytochemical assay was correlated with tumor location, histological type, histological grade, and pS2 immunocytochemical assay, but not with Ki67 immunocytochemical assay; high PR content was observed in cisternae, transitional, meningothelial, and low-grade meningiomas. Only 11 meningiomas showed more than 1% Ki67 immunoreactive nuclei. These meningiomas were usually located in the convexity and were of high histological grade. Estrogen-regulated protein immunoreactivity was observed in 34 meningiomas but the number of immunoreactive nuclei was low. The pS2 immunocytochemical assay was not related to clinicopathological features but was preferentially observed in PR-negative meningiomas. The results of this study are compared with those previously reported, and the function and regulation of PR's in meningiomas is discussed. The results indicate that 1) regulation of PR's and pS2 proteins in meningiomas differs from regulation in estrogen-dependent tissues such as breast or endometrium; 2) interruption of hormonal therapy in women presenting with a meningioma is not absolutely necessary; 3) meningiomas have different biological properties according to their clinicopathological features; and 4) future studies of hormonal clinical trials should be performed on well-defined meningioma subgroups.
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PMID:Quantitative imaging of estrogen and progesterone receptors, estrogen-regulated protein, and growth fraction: immunocytochemical assays in 52 meningiomas. Correlation with clinical and morphological data. 752 35

Autonomous expression of progesterone receptors (PR) in human meningiomas is well established. To evaluate whether, similar to progesterone receptors, other estrogen-inducible proteins are also autonomously expressed in meningiomas, concentrations of pS2 and cathepsin-D (Cath-D) were measured in 52 meningiomas. No pS2 protein was detectable in 52/52 tested meningiomas. The Cath-D protein was measurable in all 52 meningiomas, but the mean concentration of Cath-D in meningioma cytosols was 2.4-fold lower than that of a group of 54 breast tumors (p < 0.001). These results indicate that autonomous expression is a PR-related rather than an estrogen receptor-related phenomenon and, consequently, that estradiol is probably not responsible for PR synthesis in human meningiomas. To evaluate the role of other, non-estradiol-dependent signalling pathways in PR synthesis, the effects of EGF, Forskolin and phorbol ester on PR synthesis were tested in vitro. No PR was detectable after the addition of EGF to six different primary cultures. Forskolin and TPA addition caused a morphological change in meningioma cells, but did not induce PR or pS2 synthesis in two different primary meningioma cultures. We conclude that PR synthesis in human meningiomas cannot be triggered by switching on the signalling pathways activated by these growth factors.
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PMID:Progesterone receptor synthesis in human meningiomas: relation to the estrogen-induced proteins pS2 and cathepsin-D and influence of epidermal growth factor, Forskolin and phorbol ester in vitro. 968 Dec 95

The abundant expression of progesterone receptors (PR) in human meningiomas is well established. It is unknown, however, how PR expression is regulated, especially since estrogen receptors (ER) are virtually absent in these tumors. At the mRNA level, ER splice variants occur in meningioma but these appear not to be involved in the apparently autonomous PR expression. In an earlier study, because other ER-inducible proteins were either not expressed at all (pS2) or were expressed at a very low level compared to their expression in breast cancer (Cathepsin-D), the authors have postulated that the autonomous PR expression in meningioma is PR promoter-related rather than ER-related and have studied PR expression in cultured meningioma cells. PR levels appeared to decrease rapidly in vitro in monolayer as well as in three dimensional spheroid cultures. Culture conditions thus are not yet sufficient for the quantitative evaluation of PR expression. To evaluate whether PR deterioration is associated with cell turnover (meningiomas grow much faster in vitro than in vivo), the relationship between expression of the apoptotic proteins Bcl-2 and Bax and PR expression was investigated. Bcl-2 expression was found to be highest in meningioma with low PR levels, and in breast cancer tissue with high PR levels. Bax expression was not related to PR expression in any of the two tissues. Given the potential benefit of antiprogestin treatment and the occurrence in meningiomas of a protein capable of binding to the estrogen-responsive element, the expression of PR in meningioma remains a fascinating phenomenon which requires further investigation.
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PMID:Occurrence, regulation, and significance of progesterone receptors in human meningioma. 1110 90