Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04626 (erbB-2)
 5,251 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Uterine carcinosarcoma histologically comprises the components of epithelial and mesenchymal malignancies, and is known to be clinically highly aggressive. To reveal the significance of the expression of tyrosine-kinase-receptor-type oncoproteins in this tumor type, the incidence and distribution of the KIT, EGFR, and HER-2 (c-erbB-2) oncoproteins were immunohistochemically examined in 16 surgically resected cases. For 6 cases, the EGFR and HER-2 amplifications were also examined by fluorescence in situ hybridization (FISH). In the epithelial component, overexpressions of KIT, EGFR, and HER-2 were detected in 4 (25%), 5 (31%), and 9 (56%) cases, respectively, whereas these overexpressions in the mesenchymal component were detected in 6 (38%), 8 (50%), and 1 (6%) cases, respectively. KIT and EGFR were co-overexpressed in the mesenchymal component of 4 cases and in the epithelial component of 2 cases. However, HER-2 overexpression was mostly detected in the epithelial component only, and tended to occur independently of KIT and/or EGFR overexpression. By FISH, one of the 4 cases with HER-2 overexpression showed low-level gene amplification. In two cases with EGFR overexpression, the gain of EGFR alleles and/or polyploidization of chromosome 7 had occurred. The expression patterns of KIT, EGFR, and HER-2 differed between the epithelial and mesenchymal components, and the regulation of their expression appeared important in the acquisition of mesenchymal metaplasia in uterine carcinosarcoma. Structural and/or numerical alterations of chromosomes might be in part involved in EGFR and/or HER-2 overexpression in this tumor type.
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PMID:Different expression patterns of KIT, EGFR, and HER-2 (c-erbB-2) oncoproteins between epithelial and mesenchymal components in uterine carcinosarcoma. 1461 76

Although KIT and EGFR overexpressions are reported to occur in breast cancer, their pathological significance is still unclear. We examined KIT, EGFR, and c-erbB-2 overexpressions immunohistochemically in 150 cases of surgically resected breast cancer and their correlation with the histological type and grade and mesenchymal and/or myoepithelial immunophenotype of primary tumors. To facilitate the analysis, we constructed a tissue microarray comprising 2-mm diameter tissues cored from the representative tissue block of each tumor. KIT, EGFR, and c-erbB-2 overexpressions were detected in 15 (10%), 12 (8%), and 23 (15%), respectively. The KIT was more frequent in the group comprising comedo-type ductal carcinoma in situ and invasive ductal carcinomas (IDCs) of the solid-tubular subtype than in the group of other histological types (P=0.027), and the EGFR was more frequent in IDCs of solid-tubular type than in other histological types (P <0.05). KIT and EGFR overexpressions were correlated with nuclear grade 3 (P=0.0095 and 0.0005) and tended to be concurrent (P=0.005). KIT overexpression was correlated with vimentin and S-100 expression (P=0.003 and P=0.005), and EGFR overexpression was correlated with S100 expression (P=0.0001). These correlations with grade and mesenchymal/myoepithelial markers were not observed for c-erbB-2 overexpression. KIT and EGFR appeared to be indicators of high-grade breast carcinoma groups that often contain the carcinomas with mesenchymal and/or myoepithelial differentiation, which are distinct from the group with c-erbB-2 overexpression.
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PMID:Correlation of KIT and EGFR overexpression with invasive ductal breast carcinoma of the solid-tubular subtype, nuclear grade 3, and mesenchymal or myoepithelial differentiation. 1564 55

It was hypothesized that four histopathological types or subtypes of breast carcinoma were undifferentiated types characterized by bidirectional differentiation toward both luminal epithelial and myoepithelial cells and had characteristic molecular changes: invasive ductal carcinoma (IDC) with a large central acellular zone, atypical medullary carcinoma (a subgroup in Grade 3 solid-tubular carcinoma), matrix-producing carcinoma, and spindle-cell carcinoma (or carcinoma with spindle-cell metaplasia). In 32 cases of the undifferentiated type and 37 cases of the relatively differentiated types, we immunohistochemically examined the expressions of myoepithelial markers and KIT, epidermal growth factor receptor (EGFR), and c-erbB-2 oncoproteins. Vimentin, S-100, and alpha-smooth muscle actin were positive in 28 (88%), 22 (69%), and 15 (47%) of the undifferentiated types, but were positive in seven (19%), one (3%), and one (3%) of relatively differentiated types (P < 0.0001). KIT and EGFR overexpressions were detected more frequently in the undifferentiated types (34 and 88%, respectively) than in relatively differentiated types (3 and 3%, respectively) (P < 0.0001, for both). In 11 (85%) of 13 cases with KIT overexpression, EGFR overexpression concurred. c-erbB-2 overexpression was almost equally detected in both the undifferentiated and relatively differentiated types, and did not correlate with KIT or EGFR overexpression. Phosphotyrosine was detected in 16 (67%) of 24 cases with KIT, EGFR, and/or c-erbB-2 overexpression but only in six (18%) of 34 cases without KIT, EGFR, or c-erbB-2 overexpression (P = 0.0002). The undifferentiated-type breast carcinomas appeared to show mammary epithelial stem cell-like features, and they could be identified by KIT and/or EGFR overexpressions.
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PMID:Frequent KIT and epidermal growth factor receptor overexpressions in undifferentiated-type breast carcinomas with 'stem-cell-like' features. 1595 55

Metaplastic breast carcinoma, a rare tumor composed of adenocarcinomatous and nonglandular growth patterns, is characterized by a propensity for distant metastases and resistance to standard anticancer therapies. We sought confirmation that this tumor is a basal-like breast cancer, expressing epidermal growth factor receptor (EGFR) and stem cell factor receptor (KIT). EGFR activating mutations and high copy number (associated with response to tyrosine kinase inhibitor gefitinib) and KIT activating mutations (associated with imatinib sensitivity) were then investigated. Seventy-seven metaplastic cases were identified (1976-2006); 38 with tumor blocks available underwent pathologic confirmation before EGFR and KIT immunohistochemical analyses. A tissue microarray of malignant glandular and metaplastic elements was constructed and analyzed immunohistochemically for cytokeratin 5/6, estrogen receptor, progesterone receptor, and p63, and by fluorescence in situ hybridization for EGFR and HER-2/neu. DNA isolated from individual elements was assessed for EGFR and KIT activating mutations. All assessable cases were negative for estrogen receptor, progesterone receptor, and (except one) HER2. The majority were positive for cytokeratin 5/6 (58%), p63 (59%), and EGFR overexpression (66%); 24% were KIT positive. No EGFR or KIT activating mutations were present; 26% of the primary metaplastic breast carcinomas were fluorescence in situ hybridization-positive, displaying high EGFR copy number secondary to aneusomy (22%) and amplification (4%). We report here that metaplastic breast carcinoma is a basal-like breast cancer lacking EGFR and KIT activating mutations but exhibiting high EGFR copy number (primarily via aneusomy), suggesting that EGFR tyrosine kinase inhibitors should be evaluated in this molecular subset of breast carcinomas.
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PMID:Molecular analysis of metaplastic breast carcinoma: high EGFR copy number via aneusomy. 1841 8

Salivary duct carcinomas (SDCs) and adenoid cystic carcinomas (ACCs) are the most aggressive and the most frequent carcinomas of the salivary glands, respectively. Little is known about them in terms of molecular/biochemical characterization and conventional treatments are ineffective. On cryopreserved material, we analyzed the expression/activation status of TRK-A, HER-2/neu, and KIT receptors by means of immunoprecipitation and Western blot analysis experiments, and the presence of their cognate ligands by means of Western blot analysis and/or reverse transcription-polymerase chain reaction in 9 SDCs, 12 ACCs, and 8 normal glands. The amplification status of HER-2/neu was also investigated by means of fluorescent in situ hybridization analysis on fixed material. The receptor tyrosine kinase (RTK)-deregulated profile of the SDCs was characterized by the overexpression of activated TRK-A in the presence of its ligand, and the overexpression of HER-2/neu sustained by gene amplification. The RTK signature of the ACCs was represented by the overexpression of activated KIT and TRK-A and their cognate ligands, and the overexpression of activated HER-2/neu, in the absence of gene amplification, possibly sustained by epidermal growth factor receptor heterodimerization. In conclusion, SDCs and ACCs, although sharing TRK-A autocrine loop activation, have different pathologically activated RTK-deregulated profiles that may be potential targets for pharmacological RTK inhibitors.
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PMID:TRK-A, HER-2/neu, and KIT Expression/Activation Profiles in Salivary Gland Carcinoma. 1879 22

Neuroendocrine (carcinoid) tumors (NETs) are endocrine neoplasms occurring most frequently in gastrointestinal and bronchopulmonary (BP) systems. The majority of patients present with advanced disease for which few treatment options exist. We assessed 104 NETs (74 cases) for biomarkers targeted by anticancer drugs under development for other forms of cancer. Activating mutations were assessed in epidermal growth factor receptor (EGFR), stem cell factor receptor (KIT), and platelet-derived growth factor receptor alpha (PDGFRA), as well as non-response mutations in KRAS. Copy number of EGFR and HER-2/neu was quantified with fluorescence in situ hybridization. Immunohistochemical analyses were performed for EGFR, KIT, PDGFRA, somatostatin receptor subtypes 2A and 5 (SSTR5), vascular endothelial growth factor receptor 1, mammalian target of rapamycin (mTOR), insulin-like growth factor 1 receptor (IGF1R), heat shock protein 90 (Hsp90), and transforming growth factor-beta receptor 1 (TGFBR1). NETs lacked HER2-overexpression predictive of anti-HER2 response and KIT and PDGFRA activating mutations indicative of imatinib sensitivity. High EGFR aneusomy (20% of all cases) and elevated EGFR copy number (39%) were found, but few KRAS mutations associated with non-response to anti-EGFR therapy (3%). Hsp90, TGFBR1, IGF1R, and SSTR5 exhibited highest levels of immunohistochemical staining in the largest percents of tumors. In subsequent in vitro studies, anticancer drug 17-(allylamino)-17-demethoxygeldanamycin (17-AAG) (targeting Hsp90) inhibited proliferation of BP NET lines NCI-H727, NCI-H720, and NCI-H835 with IC(50) values of 70.4, 310, and 788 nM respectively; BMS-754807 (targeting IGF1R/IR) inhibited growth with IC(50) values of 428 nM, 2.8 microM, and 1 microM. At growth-inhibiting concentrations, 17-AAG (24 h) induced loss of EGFR and IGF1R in the IGF1R-expressing NCI-H727 line, and BMS-754807 (24 h) inhibited constitutive IGF1R autophosphorylation. Our results support further research into Hsp90, IGF1R, and EGFR as targets for developing new anticancer therapeutics for some NETs.
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PMID:Molecular markers for novel therapies in neuroendocrine (carcinoid) tumors. 2038 47