Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:O76050 (neu)
 3,969 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Based on limited but compelling immunohistochemical data demonstrating individual overexpression of the tyrosine kinase growth factor receptors, c-erbB-2 and c-met, in significant percentages of human cholangiocarcinoma (ChC), we investigated if combined overexpression of both c-neu, the rat homologue of c-erbB-2, and c-met, the receptor for hepatocyte growth factor/scatter factor (HGF/SF), might represent a characteristic, early event associated with furan-induced cholangiocarcinogenesis in rat liver. Specifically, through the use of immunohistochemistry, in situ hybridization (ISH), and Western and Northern blotting, we found that both c-neu and c-met are prominently overexpressed in intestinal metaplastic lesions in early putative precancerous cholangiofibrotic tissue formed in the livers of rats after 6 weeks of furan treatment when compared with normal and hyperplastic intrahepatic biliary epithelia. We further demonstrated that c-neu and c-met are concordantly overexpressed in neoplastic glandular epithelia in later-developed primary "intestinal-type" of ChC formed in the livers of furan-treated rats, as well as in subsequently derived transplantable mucin-producing tumors. Overexpression of c-neu and c-met correlated with increased proliferating cell nuclear antigen (PCNA)-labeling indices, which were determined to be three to four times higher in intestinal metaplastic glands in precancerous cholangiofibrotic tissue and in neoplastic glands in the primary "intestinal type" of ChC than in hyperplastic bile ductular structures within either cholangiofibrotic or bile duct-ligated (BDL) livers. The c-neu and c-met receptor proteins overexpressed in different in vivo passages of a transplantable ChC each contained immunoreactive phosphotyrosines, indicating an activated state. However, we did not detect evidence of either gene amplification of c-neu or c-met or of a common transmembrane-activating mutation in c-neu expressed in transplantable ChC. Our findings indicate that altered expression of c-neu and c-met occurs relatively early in the process of furan-induced cholangiocarcinogenesis in rat liver and may play a potentially important role in its pathogenesis. They further indicate a common alteration in tyrosine kinase growth factor receptor expression linking early putative precancerous intestinal metaplastic lesions in liver to later-developed mucin-producing biliary cancer.
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PMID:Overexpression of C-NEU and C-MET during rat liver cholangiocarcinogenesis: A link between biliary intestinal metaplasia and mucin-producing cholangiocarcinoma. 1021 29

Receptor tyrosine kinases play an important role in malignant transformation of epithelial cells by activating signal transduction pathways important for proliferation, invasion and metastasis. In a pilot study (n = 40), we evaluated expression of the c-Met and Her2/neu receptor tyrosine kinases and the c-Met ligand hepatocyte growth factor/scatter factor (HGF/SF) in primary breast cancers and their lymph node metastases using both conventional immunohistochemistry and confocal immunofluorescence. Neither c-Met and HGF/SF nor Her2/neu expression correlated with established prognostic factors such as age, lymph node involvement, estrogen receptor (ER), progesterone receptor (PR), tumor size, or grade. Both staining methods confirmed a significant correlation between c-Met overexpression and a high risk of disease progression. Furthermore, among tumors with c-Met overexpression, only 50% also overexpress Her2/neu, thus identifying a subset of patients with aggressive disease in addition to Her2/neu. Median disease-free survival in patients with c-Met overexpressing tumors was 8 months compared to 53 months when c-Met expression was low (p = 0.037; RR = 3.0). This significant impact of c-Met on tumor aggressiveness independent of Her2/neu was also confirmed by multivariate analysis. In conclusion, the role of c-Met expression as a prognostic variable and consequently as an interesting target for novel therapeutic approaches deserves further analysis in a larger cohort of patients.
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PMID:C-Met overexpression in node-positive breast cancer identifies patients with poor clinical outcome independent of Her2/neu. 1545 88