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

We have conducted two series of studies, a biochemical study and an immunocytochemical study, to investigate the role of epidermal growth factor receptor (EGFR) expression in primary breast cancer patients. In the biochemical study, a consecutive 115 patients were included and EGFR was measured by a competitive binding assay with multipoint Scatchard analysis. In the immunocytochemical study comprising 126 patients, EGFR status was determined by immunostaining with anti-EGFR antibody EGFR1. Several agreements were found from these two studies. EGFR status was inversely correlated with estrogen receptor (ER) status. No significant correlation was found between EGFR status and tumor size, nodal metastases, or the expression of c-erbB-2 protein. Ki-67 immunoreactivity, a cellular proliferation marker, was enhanced in EGFR positive tumors over EGFR negative tumors, suggesting a linkage of EGFR expression to cellular proliferative activity. Post-operative follow up showed that relapse-free survival for EGFR positive patients was significantly worse than that for EGFR negative patients, particularly in node-positive patients. Multivariate analysis demonstrated a significance of EGFR status as an independent prognostic indicator in primary breast cancer. The group expressing EGFR and c-erbB-2 protein indicated a particularly high risk for relapse.
 ...
PMID:Role of epidermal growth factor receptor expression in primary breast cancer: results of a biochemical study and an immunocytochemical study. 791 67

The prognostic value of c-erbB-2 protein overexpression has been evaluated in 463 patients with operable breast cancer after a median follow-up of 66 months. Overexpression was observed in 99/463 (21%) of the breast tumors. It showed significant positive correlation to histological grade (p < 0.0001) and tumor size (p < 0.02). A relationship of borderline significance was observed between c-erbB-2 protein overexpression and negative or low estrogen receptor (ER) content. No significant correlation was found to lymph node involvement or proliferating tumor cell fraction as determined by the proliferating cell nuclear antigen (PCNA). After a median follow-up of 66 months (range 6 to 109 months), the overall survival of all patients amounted to 63%. Multivariate analysis revealed lymph node involvement, tumor size, histological grade, histological type, c-erbB-2 protein overexpression, progesterone receptor (PR) content, and oral contraceptive use as independent prognostic factors. In an univariate analysis, the overall survival amounted to 72% and 38% of tumor patients with negative and positive c-erbB-2 protein overexpression, respectively. The most significant finding is that c-erbB-2 overexpression has been recognized as an independent predictive factor in subsets of tumor patients who would be expected to have a generally poor prognosis, such as those indicating axillary lymph node involvement, large tumor size (> 2 cm), and PR negativity.
 ...
PMID:C-erbB-2 overexpression in primary breast cancer: independent prognostic factor in patients at high risk. 791 7

Salivary duct carcinoma is an infrequent highly aggressive salivary gland tumor that is histologically similar to ductal carcinoma of the breast. We studied 13 cases by immunohistochemistry for the presence of estrogen and progesterone receptors, cathepsin D, and c-erbB-2 protein to determine whether the similarity to breast carcinoma extended beyond the light microscope to the molecular level and, if so, whether these markers might have therapeutic or prognostic value. Twelve of 13 cases contained sufficient amounts of tumor tissue for evaluation. Of these 12 cases, one (8%) was positive for estrogen receptors, none was positive for progesterone receptors, five (42%) were positive for cathepsin D, and three (25%) were positive for c-erbB-2 protein. Expression of cathepsin D and c-erbB-2 protein does not appear to have prognostic significance in salivary duct carcinoma. The 8% incidence of immunopositivity for estrogen receptors and absence of progesterone receptors in salivary duct carcinoma is considerably less than that seen in breast cancer. Nevertheless, because the occurrence of systemic metastasis in salivary duct carcinoma is such an ominous development largely unresponsive to chemotherapy, antihormonal therapy, such as used in breast cancer, might be considered on a trial basis for those tumors that are estrogen receptor-positive when conventional therapeutic modalities fail.
 ...
PMID:Salivary duct carcinoma. Part II. Immunohistochemical evaluation of 13 cases for estrogen and progesterone receptors, cathepsin D, and c-erbB-2 protein. 791 29

ErB-2 protein levels in breast cancer tissue extracts were determined by an enzyme immuno assay (ErbB-2 EIA "Nichirei") using anti-c-erbB-2 monoclonal antibodies, and compared with the c-erbB-2 gene amplification detected by dot blot hybridization or differential PCR, and with the overexpression detected by immunostaining. The positivities of c-erbB-2 gene amplification and overexpression in breast cancer tissues were 25.0% (14/56) and 39.3% (46/117), respectively. The cut-off values of the Erb B-2 protein in tissue extract by EIA were set at 18.0 ng/mg-protein for gene amplification and 10.4 ng/mg-protein for overexpression, respectively, from the data of breast cancer tissues which were negative for c-erbB-2 gene. The accuracy of the ErbB-2 protein levels in tissue extract with c-erbB-2 gene amplification and overexpression were 90.6% and 79.2% using these cut-off values respectively. The result of c-erbB-2 gene amplification, overexpression, and ErbB-2 protein levels were significantly correlated with negative estrogen receptor (ER) and progesterone receptor (PgR) status in tissue cytosol fraction. These results indicate that measurement of ErbB-2 protein in tissue extract is useful to estimate the c-erbB-2 gene amplification and/or overexpression in breast cancer tissues.
 ...
PMID:[Clinical evaluation of ErbB-2 protein in tissue extract using an enzyme immuno assay (ErbB-2 EIA "Nichirei")]. 791 82

The expression of transforming growth factor-alpha (TGF-alpha), epidermal growth factor receptor (EGF-R) and oncogenes c-erbB-2, c-H-ras, c-myc, as well as estrogen (ER) and progesterone (PR) receptors were studied immunohistochemically in the tissue of 21 benign and 58 malignant human breast lesions. Twenty nine (50%) of 58 carcinomas were positive for EGF-R and c-erbB-2 product, 55 (94.8%) for c-myc product, 9 (15.5%) for c-H-ras product and 17 (29%) for TGF-alpha. Eighteen of 58 (31%) carcinomas were estrogen receptor positive and 22 (38%) were positive for progesterone receptor. No correlation was found between expression of each investigated parameter and the clinical stage or degree of histological differentiation of the carcinomas. However, a significant positive correlation was observed between lymph node involvement and c-erbB-2 and EGF-R/c-erbB-2 positive tumors. A strong correlation was also observed between high levels of EGF-R and low levels of estrogen receptor. In 15 of 17 cases we found simultaneous expression of EGF-R and TGF-alpha. We also found interesting patterns in concomitant expression of the investigated parameters suggesting a possible cascade of events that occur in breast cancer cells.
 ...
PMID:Immunohistochemical detection of TGF-alpha, EGF-R, c-erbB-2, c-H-ras, c-myc, estrogen and progesterone in benign and malignant human breast lesions: a concomitant expression. 791 21

The c-erbB-2 oncogene is frequently amplified and overexpressed in human breast cancer. We have studied the c-erbB-2 protein in conjunction with DNA content in frozen samples from breast cancers using flow cytometry. The cell suspensions were obtained by mechanical disaggregation followed by a short fixation in 1% paraformaldehyde. The level of c-erbB-2 expression was calculated as a fluorescence index, taking into account the relative amount of total cellular fluorescence compared to nonspecific fluorescence. The flow cytometric value correlated with immunohistochemical results obtained with the same monoclonal antibody (c-neu, clone 9G6). Overexpression of c-erbB-2 was significantly more frequent in DNA aneuploid tumors than in DNA diploid ones and correlated with increasing S-phase fraction and estrogen receptor negativity. In 10 DNA multiploid tumors, the different aneuploid stemlines uniformly expressed c-erbB-2, supporting the hypothesis that overexpression is an early event in breast cancer. Of the 172 tumors, the 37 (22%) judged as positive with immunohistochemistry showed a somewhat higher rate of distant recurrence than others (P = 0.14). The fluorescence index was significantly associated with prognosis (P = 0.0012), as it was also among the immunohistochemically positive cases. If the degree of overexpression is important, then flow cytometry could be a feasible technique for classification.
 ...
PMID:Simultaneous analysis of c-erbB-2 expression and DNA content in breast cancer using flow cytometry. 792 85

The relative expression of estrogen receptor (ER) and progesterone receptor (PR) mRNA transcripts was measured in 71 primary breast-cancer biopsies. ER and PR binding activity were estimated in parallel by the dextran-coated-charcoal method. There was a close correlation between the amount of ER mRNA and estradiol binding activity. Tumors from post-menopausal patients contained higher levels of ER mRNA than those from pre-menopausal patients. Northern-blot analysis indicated the presence of a major band of 6.3 kb in all ER mRNA-positive tumors. Some tumors showed, in addition, 3.7- and 2.4-kb transcripts. PR binding activity and overall PR mRNA levels correlated moderately. PR mRNA and ER mRNA were associated. Four PR mRNA species with estimated sizes of 11.4, 4.5, 3.7 and 2.5 kb were detected in 14% of the PR mRNA-positive tumors. The 3.7-kb transcript was detected to varying degrees in all PR mRNA-positive biopsies, accompanied in some tumors by the 2.5-kb species. ER and PR mRNA levels > or = 50 pg/5 micrograms total RNA correlated with prolonged survival of the patients. In addition, high ER mRNA levels were associated with absence or minimal necrosis and vascular invasion together with absence or minimal level of tumor lymphocytic infiltration, but not with age, clinical stage, tumor size or overexpression of c-myc or c-erbB-2 mRNA. PR mRNA was not statistically associated with any of the above clinicopathological features. A bivariate analysis showed that both ER and PR mRNA levels were able to predict overall survival independently of the lymph-node status.
 ...
PMID:Estrogen and progesterone receptor mRNA levels in primary breast cancer: association with patient survival and other clinical and tumor features. 792 40

The expression of epidermal growth factor receptor (EGF-R), c-erbB-2 proto-oncogene, and estrogen receptor (ER) was studied immunohistochemically in a series of 97 human papillomavirus (HPV) lesions of the uterine cervix, with special emphasis on their association with the HPV type, grade of intraepithelial neoplasia (CIN), and the natural history of the disease. EGF-R expression was found in 95 of 97 (98%) specimens, mainly in basal and parabasal cells. Diffuse nuclear and cytoplasmic staining was detected in 36 of 97 (37%) samples, of which 29 were HPV positive. This staining pattern was most prominent in HPV 18-positive and in CIN lesions. Weak or moderate c-erbB-2 expression was found in 26 of 97 (27%) specimens. Estrogen receptor expression was observed in 28 of 77 (36%) samples, epithelial staining was seen in 11 of 77 (14%), and stromal staining occurred in 24 of 77 (31%) specimens. No clear-cut associations were established between the EGF-R, c-erbB-2, or ER expression and HPV type, nor in CIN or the clinical course of HPV infections. This failure for EGF-R, c-erbB-2, and ER to be associated with the specific HPV types, grade of CIN, or the clinical course of cervical HPV lesions suggests that the assessment of these factors is of limited value in explaining the development of HPV-associated CIN and in predicting the prognosis of this disease.
 ...
PMID:Epidermal growth factor receptor, c-erbB-2 proto-oncogene and estrogen receptor expression in human papillomavirus lesions of the uterine cervix. 792 56

Several investigators, the SEER data, and the ECOG/Intergroup study have shown that patients with small tumors (< 0.5 cm) have a recurrence rate of less than 2%, compared to 20-25% for large tumors (> or = 5 cm). Nuclear grade and tumor differentiation are established indicators; however, the interobserver lack of concordance has thwarted their use in clinical trials. The presence of peritumoral lymphatic and blood vessel invasion (PLBI) is associated with a relative risk of recurrence of 4.7. The predictive value of the presence of hormone receptors in tumors is associated with a favorable disease free and overall survival difference of 8-10%; however, this advantage is being eroded by the early appearance of other factors, such as the epidermal growth factor receptor (EGFR), proliferative capacity (S-phase), nuclear grade, and HER-2/neu oncogene. Concordance among the different methods of hormone-receptor assay (immunocytochemical, sucrose gradient, and dextran-coated charcoal) is essential to refine the true value of these factors. DNA flow cytometry measurements of ploidy (DNA content) and S-phase fraction are the most characterized of the prognostic factors. There are conflicting reports regarding the clinical significance of ploidy status, while measurements of S-phase fraction clearly indicate a robust association with disease free and overall survival. Our data continue to show that S-phase, but not ploidy, can predict time to recurrence significantly in untreated patients, even when data are stratified for tumor size. HER-2/neu oncogene is expressed in about 50% of ductal carcinoma in situ and 14% of invasive ductal carcinoma. The presence of this oncogene at high copy number may be a useful independent marker of poor prognosis and may be associated with drug resistance and correlated with tumor recurrence and shorter survival. EGFR could be measured in most breast tumors, and the level of its expression has inversely correlated with estrogen receptor protein expression. The value of EGFR as a predictor of prognosis remains controversial and is still being investigated. Cathepsin-D provides a provocative biologic rationale but is hindered by different and incongruent methods of analysis. The majority of large studies with more than 3-years' follow-up suggests that high cathepsin-D levels may be predictive of greater recurrence and lower survival. Angiogenesis has been implicated as a critical component of the metastatic process. Early studies show that tumor angiogenesis is an independent and highly significant prognostic indicator, and its presence may suggest the selection of "anti-angiogenic therapy."(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Prognostic factors in early breast carcinoma. 800 12

Epidermal growth factor receptor (EGFR) overexpression correlates with both loss of estrogen receptor (ER) and poor prognosis in breast cancer. Interestingly, in normal breast EGFR appears to be expressed more frequently than in malignant tissue, and there may be a different relationship between ER and EGFR. A variety of cellular regulators, such as EGF, TGF alpha, phorbol esters, and steroid hormones, are capable of altering the level of EGFR expression in breast cells. However, much work remains to be done on the mechanistic details of EGFR regulation in this disease. The significance of EGFR as an oncogene in breast cancer is compounded by its potential interactions with other oncogenes such as c-erbB-2 and c-myc. Additionally, several recent studies have placed EGFR prominently in the signal transduction pathway, demonstrating that the EGFR-ligand system may play important roles throughout the course of malignant progression in breast cancer.
 ...
PMID:EGF receptor expression, regulation, and function in breast cancer. 801 62


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>