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)

The distribution of chromogranin/secretogranin (Cg/Sg) mRNAs, determined by Northern and in situ hybridization, was analyzed in 14 cultured pituitary adenomas characterized by immunohistochemistry and hormone secretion in a defined medium in vitro. There were 5 functional GH adenomas, 1 silent GH adenoma, 7 null cell adenomas, and 1 oncocytoma. The null cell adenomas, oncocytoma, and silent GH adenomas were also analyzed by electron microscopy. Most null cell adenomas and the oncocytoma secreted FSH and LH into the culture medium. GH adenomas, which are examples of well differentiated tumors based on morphological examination, expressed significantly more SgIII mRNA compared to the null cell adenomas and oncocytoma (70 +/- 6% vs. 22 +/- 5%; P < 0.001). GH adenomas also expressed significantly less CgA mRNA compared to the less well differentiated null cell adenomas and oncocytoma (27 +/- 6% vs. 67 +/- 4%; P < 0.001), which could be considered less well differentiated based on ultrastructural morphological features. After treatment with phorbol 12-myristate 13-acetate (10(-7) M) for 7 days, there was an increase in the mRNA for CgB and SgII mRNAs in GH and null cell tumors, while dexamethasone treatment for 7 days increased CgA mRNA in GH and null cell adenomas. GnRH treatment for 7 days increased CgB mRNA in null cell adenomas. Phorbol 12-myristate 13-acetate also decreased the percentage of immunoreactive GH cells and GHm RNA, determined by in situ and Northern hybridization analyses. These results indicate that pituitary adenomas have a distinct pattern of Cg/Sg mRNA expression, which appears to be related to the degree of morphological differentiation of these neoplasms, and suggest that the effects of secretagogues on various Cg/Sg mRNA levels may be related to the stimulation of hormone secretion.
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PMID:Differentiation of human pituitary adenomas determines the pattern of chromogranin/secretogranin messenger ribonucleic acid expression. 768 Mar 55

Several members of the chromogranin/secretogranin (Cg/Sg) family are post-translationally processed in neuroendocrine cells and tumors to smaller peptides, some of which are biologically active. For example, CgA is processed to pancreastatin, parastatin, and other peptides. We analyzed the distribution of pancreastatin and CgA proteins in normal and neoplastic pituitaries as well as the prohormone convertases PC2 and PC3/1 (PC3), the putative processing enzymes for the Cg/Sg family, in 35 pituitary adenomas and 4 non-neoplastic pituitaries by immunohistochemistry and immunoblotting with highly specific antisera. CgA and CgB mRNAs were also examined. Pancreastatin was present in all subtypes of pituitary tumors, although prolactin-secreting adenomas expressed this peptide less frequently than did other tumor types. CgA protein and CgA mRNA expression were also restricted in prolactin adenomas and in normal prolactin cells, as shown by combined in situ hybridization and immunostaining. The prohormone convertases PC2 and PC3 were present in pituitary tumors and in non-neoplastic pituitaries. Immunoblot analysis and immunostaining showed a principal approximately 69-kd PC3 band and a approximately 68-kd PC2 band. Adrenocorticotrophic hormone-secreting adenomas expressed mainly PC3 as determined by immunoblotting and immunohistochemistry, whereas all other adenoma groups expressed predominantly PC2. These results indicate that the enzymes capable of processing CgA and other members of the Cg/Sg family to peptides with biological activity such as pancreastatin are widely expressed in human pituitary adenomas and in non-neoplastic pituitaries, with adrenocorticotrophic hormone tumors expressing predominantly PC3 and other adenomas expressing mainly PC2. The infrequent expression of CgA protein and pancreastatin peptides in normal and neoplastic prolactin cells suggests a unique role of CgA in these tumors.
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PMID:Analysis of the chromogranin A post-translational cleavage product pancreastatin and the prohormone convertases PC2 and PC3 in normal and neoplastic human pituitaries. 774 13

Twenty-five pituitary adenomas were analyzed for expression of various chromogranin/secretogranin (Cg/Sg) messenger RNA (mRNA) transcripts by in situ hybridization (ISH). An additional five adenomas were also analyzed by Northern hybridization. Immunohistochemical staining for CgA and for SgIV (with monoclonal antibody HISL-19) was also performed. Most prolactin and adrenocorticotropin adenomas did not express CgA mRNA or protein, whereas growth hormone (GH) tumors had low to moderate amounts of CgA mRNA by Northern and in situ hybridization analyses and were focally positive for CgA protein. CgB, SgII, SgIII, and SgV mRNA transcripts were present in most adenomas, and SgIV protein was detected in all groups of tumors. A GH and a null cell adenoma cultured for 7 days also expressed CgA/Sg mRNA transcripts and protein. Paraffin sections of some adenomas that were negative for CgA protein had detectable CgA mRNA by in situ hybridization analysis. These results indicate that CgA mRNA and protein are more commonly expressed in glycoprotein hormone-producing tumors compared with other types of pituitary adenomas and that ISH for CgA may detect the mRNA transcripts for CgA even when CgA protein is not detected by immunohistochemistry.
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PMID:Analysis of chromogranin/secretogranin messenger RNAs in human pituitary adenomas. 816 54