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)

Amplification and overexpression of the c-erbB-2 gene in 21MT-2 and 21MT-1 human breast carcinoma cells results in progressively elevated levels of constitutively tyrosine-phosphorylated p185erbB-2 and is associated with progressive insulin-like growth factor (IGF) and combined IGF/epidermal growth factor (EGF) independence in culture. In addition, the neu differentiation factor/heregulins (HRGs), a family of ligands that activate p185erbB-2 through direct binding to erbB-3 or erbB-4, are potent mitogens for various nonneoplastic mammary epithelial cells and carcinoma cell lines in the absence of both IGF and EGF in culture. We have investigated the ability of ligand induction with HRGs or the constitutive activation of p185erbB-2 in the 21MT breast carcinoma cells to induced the recruitment of phosphatidylinositol 3-kinase (PI3K) by p185erbB-2 and erbB-3. HRG was found to potently induce the recruitment of the M(r) 85,000 regulatory subunit of PI3K by phosphotyrosine proteins in both nonneoplastic H16N-2 mammary epithelial cells (which express normal c-erbB-2 levels) and in the 21MT-2 and 21MT-1 cell lines, which were all isolated from a single patient with intraductal and invasive ductal carcinoma of the breast and express c-erbB-3 but not c-erbB-4 in culture. The activation of PI3K in these cells was also associated with high-level mitogenic responsiveness to HRG, as well as the IGF/EGF-independent proliferation of the 21MT cell lines in culture. The recruitment of PI3K by phosphotyrosine protein during ligand-induced activation, or that seen constitutively in the 21MT tumor cells, did not involve detectable tyrosine phosphorylation of p85. The HRG-induced recruitment of p85 and the constitutive recruitment of p85 in the 21MT cell lines involved direct association with both p185erbB-2 and erbB-3, although greater levels were recruited directly by erbB-3. Wortmannin, a potent inhibitor of PI3K enzymatic activity, also blocked the autonomous proliferation of the 21MT cells, and this effect was reversible in long-term cultures. These data indicate that PI3K may be an especially important mediator of HRG-induced proliferation in mammary epithelial cells and is involved in the autonomous proliferation of growth factor-independent breast carcinoma cells with c-erbB-2 gene amplification.
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PMID:Phosphatidylinositol 3-kinase recruitment by p185erbB-2 and erbB-3 is potently induced by neu differentiation factor/heregulin during mitogenesis and is constitutively elevated in growth factor-independent breast carcinoma cells with c-erbB-2 gene amplification. 873 65

Tamoxifen as sole initial therapy is gaining importance in the management of post-menopausal breast cancer patients. Age oestrogen (ER) and progesterone (PR) receptor status are accurately considered to select patients for hormonal treatment. However, additional markers are needed. By immunohistochemistry (IHC), we studied tumour expression of ER, PR, pS2, c-erbB-2 and glutathione S-transferase pi (GST pi) on initial core biopsies of 208 post-menopausal patients with a non-metastatic invasive ductal carcinoma, treated by neoadjuvant tamoxifen therapy. A good response to tamoxifen was defined as tumoral regression > or = 50% (110 patients). Relationship between response and age, tumour size, T, N, histological grade, ER and PR contents evaluated by radioimmunoassay, ER, PR, pS2, c-erbB-2 and GST pi expression evaluated by IHC were studied. Univariate and multivariate analysis showed that tumoral regression was linked only to pS2 (P = 0.004) and ER (P = 0.018) IHC expression. According to the immunohistochemical profile, three groups could be defined: pS2- and ER-positive tumours, pS2- or ER-positive tumours and pS2- and ER-negative tumours with response rates of 60%, 45% and 8% respectively. Although prospective studies are needed to confirm these results, we conclude that pS2 and ER immunohistochemical status are useful tools for predicting tumour regression with neoadjuvant tamoxifen in post-menopausal breast carcinoma patients.
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PMID:pS2 protein: a marker improving prediction of response to neoadjuvant tamoxifen in post-menopausal breast cancer patients. 885 85

Thirty cases of invasive ductal carcinoma of the breast were classified to histological subtype according to the General Rules for Clinical and Pathological Recording of Breast Cancer of the Japanese Breast Cancer Society and histologically graded using the Nottingham method and the correlation of histology with proliferative activity was investigated using bromodeoxyuridine (BrdU). In addition, the overexpression of p53 protein, c-erbB-2 oncoprotein and estrogen receptor (ER) were immunohistochemically examined in order to discuss the relationship with histological subtype and histological grade. Histological grade correlated positively to the BrdU labeling index (LI) and overexpression of p53. High grade carcinoma demonstrated c-erbB-2 more frequently and exhibited a low incidence of ER. However, no significant relationship was found between BrdU LI, overexpression of p53 and c-erbB-2 and histological subtype. These results suggest that the histological grade does represent the proliferative activity of tumor cells and that adding the histological grade to the pathological diagnosis in invasive ductal breast carcinoma may be useful from the clinicopathological aspect concerning tumor behavior.
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PMID:Histological grade in invasive ductal carcinoma of breast correlates with the proliferative activity evaluated by BrdU: an immunohistochemical study including correlations with p53, c-erbB-2 and estrogen receptor status. 886 93

Hyperplasia without and with atypia is considered to be a precursor lesion for certain breast carcinomas. The cytogenetic events and the molecular pathology involved in the multistep process from normal to invasive carcinoma are unknown. To characterise the sequence of early genetic abnormalities of chromosome 17q and their biological consequences in the pathogenesis of breast cancer, we performed immunohistochemistry on 451 breast tissues including 180 normal breast specimens, 28 hyperplastic lesions without atypia and 44 with atypia, 100 cases of ductal carcinoma in situ (DCIS) and 99 cases of invasive ductal carcinoma. We correlated the overexpression of the c-ErbB-2 protein, the histological and the recently proposed differentiation classification of DCIS with the extent of DCIS. For fluorescence in situ hybridisation (FISH) analysis, different probes spanning the 17q region including the c-erbB-2 gene locus and those which are found adjacent, were used. Reverse painting and comparative genomic hybridisation (CGH) were performed on several breast cancer cell lines. c-ErbB-2 overexpression was observed in only 29% of DCIS and 23% of invasive carcinomas, but not in hyperplastic and normal tissue. c-ErbB-2 overexpression is correlated with poor differentiation in DCIS but not in invasive carcinoma. In DCIS, there was no correlation with the histological subtype classification. The average extent of DCIS is significantly increased from 13.81 mm in c-ErbB-2 negative cases to 29.37 mm in c-ErbB-2 positive cases. The increase was considered to be a possible consequence of the overexpression and is probably due to the previously described motility enhancing effect of the c-ErbB-2 protein. The histological and differentiation classification of DCIS did not correlate with the extent of disease. Using FISH, amplified genes at 17q12, always including the c-erbB-2 gene, were detected in all cases of DCIS and invasive carcinoma with c-ErbB-2 overexpression. The centromeric region and the NF1 locus, which is located between the centromere and c-erbB-2, were not amplified in any of the DCIS and invasive breast carcinomas, but co-amplification of the myeloperoxidase gene was detected in 3/5 DCIS and 1/5 invasive carcinomas with c-ErbB-2 overexpression. In contrast to c-erbB-2, immunohistochemical overexpression of their respective gene products was not observed. FISH, reverse painting and CGH show similar amplified genes with amplified c-erbB-2 in c-ErbB-2 overexpressing SK-BR-3 and BT474 human breast cancer cells. The amplified genes are part of two different amplicons. Extensive modifications of the 17q chromosomal region, caused by translocation, were also observed in these cell lines. It is concluded that the modifications of chromosome 17q, inducing overexpression of c-ErbB-2 protein, occur at the level of transition from hyperplasia to DCIS. They are preserved in invasive carcinoma with overexpression of c-ErbB-2 protein. This had led to the hypothesis that these modifications at 17q may lead to a larger extent of DCIS.
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PMID:Amplification units and translocation at chromosome 17q and c-erbB-2 overexpression in the pathogenesis of breast cancer. 917 26

We investigated whether the presence of a fibrotic focus (FF) in the primary lesion and in lymph node metastasis is a good predictor of early tumor recurrence or death in patients with invasive ductal carcinoma (IDC). Multivariate relative risk (RR) of tumor recurrence and death according to the presence of FF in the primary tumor was estimated using the Cox proportional hazards regression model with adjustment for other prognostic factors (histologic grade, T classification, nodal status, tumor necrosis, DNA ploidy, c-erbB-2 protein expression, p53 protein expression, and labeling index of proliferating cell nuclear antigen). For the evaluation of the metastatic status in the axillary lymph nodes, RR of multivariate analysis was adjusted for the presence of FF in the metastatic tumor and the number of lymph nodes involved (1-3 and > 3). The presence of FF increased the RR of tumor recurrence significantly for the cases in all stages, and especially for those in stages I and II (RR = 6.9, P < 0.05 and RR = 25.0, P < 0.005, respectively). All cases that died of disease had FF. Among IDCs with FF, 24 cases had FF in lymph node metastasis. Significantly higher RRs of tumor recurrence and death were observed in cases with FF in lymph node metastasis than in those without it (RR = 2.0, P < 0.001 and RR = 5.9, P < 0.05, respectively). It was suggested that the presence of FF is an important predictor of early tumor recurrence or death in patients with IDCs. The presence of FF in lymph node metastatic lesions is also a significant prognostic parameter.
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PMID:Fibrotic focus in invasive ductal carcinoma of the breast: a histopathological prognostic parameter for tumor recurrence and tumor death within three years after the initial operation. 926 37

The number of primary breast cancers occurring in elderly women is increasing in Japan. Optimization of treatment regimens in this age group requires precise evaluation of the biological aggressiveness of these tumors as well as the performance status and extent of tumor spread. In 39 breast cancer patients who were at least 80 years old, we examined several parameters; the form of surgical therapy, the lymph node status, presence or absence of distant metastases, the histological type and grade of atypia, and overexpression of the c-erbB-2 oncoprotein in the cancer cells. They were correlated with the clinical outcome of the patient. Of the 33 patients who underwent a mastectomy and axillary lymph node dissection, five died from cancer recurrence. Only one out of 22 patients without lymph node metastases died from cancer, while four out of the eight patients with metastases to three or more lymph nodes died from cancer recurrence within 2.7 years of surgery. The overall survival curves also differed between patients with low-risk histological tumors or grade 1 or 2 invasive ductal carcinoma and those with grade 3 invasive ductal/lobular carcinoma. Overexpression of c-erbB-2 also affected survival. Regional recurrence occurred in three out of the six patients for whom only lumpectomy or simple mastectomy was performed. These results indicate that, although primary breast cancer occurring in patients over 80 years old was largely of low-grade malignancy, patients with three or more lymph node metastases, invasive ductal/lobular carcinomas of grade 3, or c-erbB-2 overexpression frequently exhibited an aggressive clinical course.
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PMID:Clinicopathological characteristics of primary breast cancer in older geriatric women: a study of 39 Japanese patients over 80 years old. 931 Jan 43

In order to establish nude mice model of early and advanced breast cancers, 15 in-situ breast carcinomas and 31 invasive breast carcinomoas were transplanted in 155 nude mice subcutaneously. A slow-release pellet of 17-beta estradiol was also implanted subcutaneously. During ten months of observation, the in-situ breast cancer tissue eventually did not grow. Light microscopy showed that the implants kept the structure of in-situ carcinoma without invasion. Of 31 invasive carcinomas, only one diagnosed pathologically as multifocal dedifferentiated ductal carcinoma grew well and was serially passaged. It was estrogen- and progesterone-receptor negative, p53 protein negative and c-erbB-2 protein positive. Its DNA ploidy was near tetraploidy.
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PMID:[Transplantation of human primary in-situ and invasive breast carcinoma in nude mice]. 938 65

c-erbB-3, A recently identified member of the type I tyrosine kinase receptor family, has been shown to be overexpressed in invasive ductal carcinoma of breast. In this study, expression of the c-erbB-3 protein was examined in 57 cases of pure ductal carcinoma in situ of the breast (DCIS) by immuno-cytochemical methods. Staining was either absent (17 cases), present at levels equivalent to that found in adjacent normal tissue (20) or greater than in normal tissue (20). In most cases the pattern of staining was cytoplasmic, but in 4 cases with the most intense reaction there was also focal membrane staining. In the same series of cases, c-erbB-2 protein had previously been shown to be overexpressed in 28 of 57 cases, c-erbB-2 overexpression was correlated with normal level of c-erbB-3, and lack of c-erbB-2 expression was correlated with c-erbB-3 overexpression.
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PMID:c-erbB-3 protein expression in ductal carcinoma in situ of the breast. 947 Aug 44

A 44-year-old woman presented with a right huge axillary mass. Both mammography and ultrasonography revealed a primary cancer of 2.8 cm maximum diameter in the right breast and metastases in the axillary lymph nodes, both being confirmed by aspiration cytology as ductal carcinoma. Right standard radical mastectomy with level III axillary lymph node dissection was carried out. Pathologically, the tumor was diagnosed as ductal carcinoma in situ with microinvasion (DCISM), histologic grade 3. The area of stromal invasion measured 1 mm at its widest point. Sixteen of the 17 resected axillary lymph nodes contained metastases, including six level III lymph nodes. Immunohistochemical studies of the tumor revealed overexpression of p53 protein, but not that of c-erbB-2 protein. The frequency of lymph node metastases from DCISM is reported to be very low. Therefore, the present case with extensive involvement of level III lymph nodes was unusual.
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PMID:Microinvasive breast carcinoma with extensive involvement of level III axillary lymph nodes: a case report. 949 Nov 42

In tumors, resistance to chemotherapeutic drugs that alkylate the O6 position of guanine correlates with the levels of the DNA repair protein, O6-alkylguanine DNA alkyltransferase (AGT). The expression of AGT gene in human breast tumors was evaluated at the level of the single cell, to better understand the distribution of alkylation resistant cells within the tumor. Compared to normal breast ductal cells, the level of AGT expression in the breast tumor cells increased 2-fold. There was no significant association between AGT expression and tumor grade and metastatic malignancy. The up-regulation of AGT was not directly linked to the expression of cyclins D1 and D3, estrogen receptor, p53 and c-erbB-2, genes involved in cell cycle regulation and tumor growth. The elevated expression of AGT in human breast ductal carcinoma cells appeared to be a general characteristic of breast tumors, and suggests that prior treatment with analogs of O6-alkylguanine that inactivate AGT protein, should render the AGT expressing tumor cells sensitive to drugs that alkylate O6-guanine.
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PMID:Expression of the O6-alkylguanine-DNA alkyltransferase gene is elevated in human breast tumor cells. 949 26


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