Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using the thyroid follicular cell as a model for multi-stage carcinogenesis, we have investigated the role of two potential negative growth regulators ('anti-oncogenes') in epithelial tumour progression--transforming growth factor-beta 1 (TGF beta 1) and p53. Normal follicular cells, as expected, showed marked growth inhibition in response to TGF beta 1. Adenoma cells were equally inhibited. In contrast, spontaneously and SV40-immortalised follicular cell lines showing features of malignant transformation (notably loss of growth factor dependence) had lost all responsiveness to TGF beta 1, accompanied by a partial loss of its receptors. p53 protein was below detectable limits in normal and in adenoma cells but in contrast very high levels were observed in all three transformed lines. In the SV40-immortalised cells, this was expected in view of the known stabilising effect of the viral large T protein. In the spontaneous line we found strong evidence for point mutation of p53, which is known to have the same effect. Both mechanisms result in loss of p53 tumour suppressor function despite increased protein content. We conclude that loss of inhibition by TGF beta and inactivation of p53 are important steps in in vitro immortalisation and/or in vivo tumour progression in human thyroid follicular cells, and speculate that p53 may mediate or be required for the inhibitory signal normally induced by TGF beta 1.
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PMID:Correlated abnormalities of transforming growth factor-beta 1 response and p53 expression in thyroid epithelial cell transformation. 182 Sep 69

It is well known that TSH is the main factor responsible for thyrocyte proliferation and growth. Recent studies have shown that other growth factors, including transforming growth factor-beta 1 (TGF-beta 1), have an important role in the control of thyrocyte proliferation and differentiation. The aim of the study was to evaluate the expression of the TGF-beta 1 gene in thyroid follicular adenoma (FA) by Northern analysis, and its protein localization by immunohistochemistry. Surgically removed thyroid tissue from 56 patients with thyroid FA was screened for the study. Normal thyroid tissue from 4 patients with papillary carcinoma was used as a control. Sixteen FA (8 with a "cold" and 8 with a "hot" scintiscan pattern) having homogeneous histological characteristics were subsequently selected. FA showed greater TGF-beta 1 gene expression than control tissue. There was not a statistically significant difference between "cold" and "hot" FA. Immunohistochemistry analysis showed that TGF-beta 1 was located in various histological structures of the adenomas (thyrocytes, endothelium, perinervium and connective tissue); on the other hand, perinodular and control tissue did not show appreciable TGF-beta 1 protein. Our data suggest that TGF-beta 1 may be involved in the pathogenesis of FA. The different TGF-beta 1 distribution in thyrocytes, endothelium, perinervium and connective tissue in FA suggests that TGF-beta 1 may be variably expressed during the natural history of FA. Since no significant difference in TGF-beta 1 gene expression between "hot" and "cold" adenomas was found, it appears that other factors are involved in their functional differentiation.
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PMID:Transforming growth factor-beta 1 is more expressed in thyroid follicular adenoma than in normal tissue. 807 17

Using the differential display method, latent transforming growth factor-beta 1 (TGF-beta 1) binding protein 1 (LTBP-1) mRNA was identified as one of the enriched mRNAs in ovarian carcinoma tissues after isolation of genes responsible for the development of ovarian cancer. Semi-quantitative reverse transcription (RT)-PCR analysis showed that expression of LTBP-1 and TGF-beta 1 mRNAs was much higher in both serous and mucinous adenocarcinomas than in their benign counterparts, including serous and mucinous cystadenomas and cystadenomas of low malignant potential (LMPs). Immunohistochemical analysis demonstrated that only proliferating benign adenoma cells were immunoreactive for both LTBP-1 and TGF-beta 1 proteins. In contrast, most serous and mucinous adenocarcinoma cells and their surrounding stroma were intensely immunoreactive for LTBP-1 and TGF-beta 1. LTBP-1 and TGF-beta 1 proteins, and their complex forms were identified in ovarian carcinoma cell lines and in their culture media by western blot analysis, suggesting these products were produced in ovarian carcinoma cells. RT-PCR analysis demonstrated that LTBP-1L, one of the LTBP-1 transcripts that has a strong activity in targeting the latent form of TGF-beta 1 to extracellular matrix (ECM), was predominantly expressed in ovarian carcinomas. Taken together, the results suggest that upregulation of LTBP-1 in ovarian carcinoma cells may have an important role in distributing TGF-beta1 in the stromal tissues surrounding carcinoma cells.
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PMID:Overexpression of latent transforming growth factor-beta 1 (TGF-beta 1) binding protein 1 (LTBP-1) in association with TGF-beta 1 in ovarian carcinoma. 1137 59