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)

Drawing upon the comprehensive population-based Northern Alberta Breast Cancer Registry containing 704 patients with histologically negative axillary lymph nodes who have been followed for 5-16 years, we have undertaken a retrospective case-control study to evaluate the utility of genomic amplification of specific protooncogenes [c-erbB-2 (nee HER-2/neu), c-erbA, c-myc, int-2, and hst-1] as predictive indicators of clinical outcome in node-negative disease. To this end, 115 women with node-negative breast cancer who had recurred at any time up to 16 years posttreatment (cases) were matched pairwise for appropriate clinicopathological variables (size of primary tumor, menopausal state, estrogen receptor status, anniversary year of treatment, and patient age) with a second group of 115 women (controls) selected from a cohort of 502 node-negative patients who had not relapsed during long-term follow-up. Tumor DNA extracted from archival formalin-fixed, paraffin-embedded tissue blocks were analyzed for protooncogene copy number by slot-blot hybridization. Taking a gene copy number of 3 as the cutoff, 27 of the 230 tumor samples examined contained from 3- to 22-fold elevation in c-erbB-2 genomic equivalents. Twenty-one of the 27 tumors amplified for c-erbB-2 were derived from cases and 6 from controls, signifying that 18% of the node-negative patients who had relapsed harbored excessive copies of the protooncogene in their malignant tissue compared to only 5% for the patients who had remained in remission. Accordingly, the occurrence of amplification of c-erbB-2 proved to be a statistically significant predictor of poor prognosis, especially disease-free interval (P = 0.006). Moreover, this genetic alteration appeared to be independent of and to have greater predictive power than most commonly used prognostic factors. Our findings also indicated that as a clinical test, measurement of c-erbB-2 amplification suffers from low sensitivity; however, when greater than 6 gene copies are present, the test has a positive predictive value for recurrence of 70%. Concurrent analysis of tumor DNA blots with probes for the other four protooncogenes examined revealed that their amplification, which others have reported to arise often, especially in node-positive disease, was seldom found even in our high-risk case group (2-3%). In short, our data strongly suggest that amplification of c-erbB-2 may contribute to the pathogenesis of some forms of node-negative breast cancer and thus may serve as a useful genetic marker to identify a subset of high-risk patients.
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PMID:Correlation between c-erbB-2 amplification and risk of recurrent disease in node-negative breast cancer. 167 Jul 62

Data regarding the prognostic value of HER-2/neu protein expression in breast cancer are conflicting, perhaps because of short follow-up and technical difficulties in the determination (the admixture of benign elements with the biochemical method and the subjectivity of the immunohistochemical assessment). Therefore, using digital image processing, we compared the correlation between and the prognostic value of (a) quantitative immunohistochemical HER-2/neu protein expression and (b) clinical, morphometric, and flow-cytometric DNA ploidy features; histologic grade; and biochemically assessed estrogen receptor content. Paraffin-embedded invasive breast Pancers of 82 patients with long-term follow-up were used. None of the patients had received adjuvant systemic therapy. HER-2/neu protein expression was significantly correlated with DNA index, lymph node status, and tumor size and, in the diploid tumors, was weakly correlated with the percentage of S-phase cells. Strong HER-2/neu protein expression was associated with a worse prognosis (although not significantly, p = 0.07). No differences were detected between cancers with or without axillary lymph node metastases. In survival analysis, the Multivariate Prognostic Index and the morphometric features were much stronger prognosticators than HER-2/neu protein overexpression, which, however, had additional prognostic value to that of many of the features analyzed, especially when more than 35% HER-2/neu protein levels (relative to the high expression SKBR3 cell line) were present. Combined diploidy and HER-2/neu protein content greater than 35% occurred in a small group of patients (n = 3), all of whom died. Likewise, in tetraploid cancers a combination of S-phase cells greater than or equal to 7% and HER-2/neu protein content greater than 35% was an ominous sign. In multivariate analysis, strong HER-2/neu protein overexpression was prognostically over-shadowed by the morphometric features. Nevertheless, it is important to further analyze the intriguing possibility of identifying a subgroup of breast cancer patients with a very poor outcome merely using cytometric analysis of paraffin-embedded material of the primary tumor.
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PMID:Comparative long-term prognostic value of quantitative HER-2/neu protein expression, DNA ploidy, and morphometric and clinical features in paraffin-embedded invasive breast cancer. 167 89

The relationship between c-erbB-2 gene expression (assessed immunohistochemically), S-phase fraction (SPF) and prognosis has been analysed in 172 women with primary breast cancer. c-erbB-2 staining was independent of age, tumour size, number of nodes involved, tumour grade and DNA ploidy, but was more common in oestrogen receptor (ER) negative tumours (P = 0.02) and progesterone receptor (PgR) negative tumours (P = 0.03). A weak correlation between c-erbB-2 staining and SPF was observed (r = 0.18). Amongst women with node negative disease, SPF was significantly related to relapse free survival (RFS, P = 0.04) while c-erbB-2 staining was not (P = 0.2). In contrast, both SPF (P = 0.002) and c-erbB-2 staining (P = 0.016) provided significant prognostic information on RFS for women with node positive disease. Multivariate analysis showed that c-erbB-2 staining and SPF gave independent information on RFS for women with node positive disease.
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PMID:The relationship between c-erbB-2 expression, S-phase fraction and prognosis in breast cancer. 167 55

The erbB-2 gene product, gp185erbB-2, unlike the structurally related epidermal growth factor (EGF) receptor (EGFR), exhibits constitutive kinase and transforming activity. We used a chimeric EGFR/erbB-2 expression vector to compare the mitogenic signaling pathway of the erbB-2 kinase with that of the EGFR, at similar levels of expression, in response to EGF stimulation. The EGFR/erbB-2 chimera was significantly more active in inducing DNA synthesis than the EGFR when either was expressed in NIH 3T3 cells. Analysis of biochemical pathways implicated in signal transduction by growth factor receptors indicated that both phospholipase C type gamma (PLC-gamma) and the p21ras GTPase-activating protein (GAP) are substrates for the erbB-2 kinase in NIH 3T3 fibroblasts. However, under conditions in which activation of the erbB-2 kinase induced DNA synthesis at least fivefold more efficiently than the EGFR, the levels of erbB-2- or EGFR-induced tyrosine phosphorylation of PLC-gamma and GAP were comparable. In addition, the stoichiometry of tyrosine phosphorylation of these putative substrates by erbB-2 appeared to be at least an order of magnitude lower than that induced by platelet-derived growth factor receptors at comparable levels of mitogenic potency. Thus, our results indicate that differences in tyrosine phosphorylation of PLC-gamma and GAP do not account for the differences in mitogenic activity of the erbB-2 kinase compared with either the EGFR or platelet-derived growth factor receptor in NIH 3T3 fibroblasts.
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PMID:The erbB-2 mitogenic signaling pathway: tyrosine phosphorylation of phospholipase C-gamma and GTPase-activating protein does not correlate with erbB-2 mitogenic potency. 167 40

An immunohistochemical study was performed on 211 primary breast carcinomas for c-erbB-2 expression. All patients had involvement of axillary lymph nodes and all were randomised onto one of the Ludwig Breast Cancer Trials I-IV between July 1978 and August 1981. c-erbB-2 overexpression significantly correlated with high S-phase fraction, four or more positive axillary nodes involved, estrogen receptor negative primaries, progesterone receptor negative primaries, high grade tumours and DNA aneuploidy. With a nine year median follow-up c-erbB-2 positive tumours had worse disease-free survival (p = 0.0002) and overall survival (p less than 0.0001). Multivariate analyses using proportional hazard regression models demonstrated that c-erbB-2 positivity continued to predict a poor outcome even when accounting for the effects of other prognostic factors.
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PMID:Association of c-erbB-2 expression and S-phase fraction in the prognosis of node positive breast cancer. 167 97

The structure and expression of the proto-oncogene c-erbB-2 was studied in 86 patients with transitional cell carcinoma. Initial tissue samples comprised 37 grade 1, 32 grade 2 and 13 grade 3 tumours and four cases of carcinoma in situ. At the time of this first tumour sample, amplification of the c-erbB-2 gene was demonstrated by Southern blotting in 1/37 grade 1, 5/32 grade 2 and 6/13 grade 3 tumours (0.005 less than P less than 0.01). Tumour 're-occurrences' were obtained from 23 of these patients on one or more occasions. Amplification was detected in re-occurrences from seven of these 23, none of whom showed amplification in the first tumour sample. DNA was also extracted from exfoliated cells in urine collected from five cases of carcinoma in situ and c-erbB-2 amplification was demonstrated in one of these. No gene amplification was identified in patients' lymphocytes, ten biopsies of normal urothelium and 22 various intravesical pathologies. Increased expression of c-erbB-2 mRNA correlated with amplification of the gene. In addition, raised levels of mRNA were seen in the absence of gene amplification in six tumours. Immunoblotting using the polyclonal antibody 21N, raised against the c-terminus of the c-erbB-2 protein demonstrated increased amounts of a 185 kD immunoreactive protein in tumours with increased c-erbB-2 gene copy number compared with control tissues. In some tumours with high c-erbB-2 gene copy number, a 155 kD immunoreactive protein not detected in controls was expressed at higher level than the 185 kD protein. Immunocytochemistry using a monoclonal antibody AB-3, raised against the c-terminus of the c-erbB-2 protein, showed a positive reaction in the cytoplasm and cell membrane of tumours with gene amplification and in 40% of tumours with no amplification. An association was found between c-erbB-2 amplification and over-expression and the development of tumour re-occurrences. We suggest that c-erbB-2 amplification and over-expression may provide a useful molecular marker in transitional cell carcinoma of the bladder and merits further investigation as a potential prognostic indicator.
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PMID:Amplification and over-expression of c-erbB-2 in transitional cell carcinoma of the urinary bladder. 167 27

An antigen, immunologically related to the external domain of the c-erbB-2 (HER-2/neu) protein, was found shed into the serum of nude mice bearing tumors that overexpress the c-erbB-2 protein (gp185). Utilizing paired combinations from a panel of monoclonal antibodies (TAbs 250-265), with specificity for extracellular epitopes of gp185, an immunoradiometric assay was developed to quantitate this shed antigen. The immunoradiometric assay detected membrane-bound and soluble gp185 as well as a soluble derivative corresponding in sequence to the extracellular domain of gp185 (designated gp75). This recombinantly expressed gp75 was immunoaffinity purified and used to generate a standard curve from which serum samples were quantitated. Increases in antigen levels measured in the sera of tumor-bearing nude mice correlated with both overexpression of the c-erbB-2 protein and increased tumor volume. Positive sera were obtained from mice given implants of NIH3T3 cells transfected with c-erbB-2 complementary DNA (NIH3T3t), or ovarian (SK-OV-3) or breast (MDA-MB-361) tumor cell lines overexpressing the c-erbB-2 protein. In mice bearing NIH3T3t tumors, increases in tumor volume from 80 to 9000 mm3 resulted in levels of shed antigen from 8 to greater than 1000 ng/ml gp75 equivalents. Sera from mice with c-erbB-2-negative tumors or tumors overexpressing the epidermal growth factor receptor were negative in the assay. This assay, and the quantitation of shed antigen levels, may have diagnostic or monitoring utility in cancers, such as breast and ovarian, in which the c-erbB-2 protein is overexpressed.
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PMID:An antigen immunologically related to the external domain of gp185 is shed from nude mouse tumors overexpressing the c-erbB-2 (HER-2/neu) oncogene. 167 37

HER-2/neu oncoprotein overexpression was compared in fresh frozen and paraffin-embedded formalin-fixed invasive breast cancer material from the same patients. The HER-2/neu protein was detected by an immunohistochemical staining method, and the average amount of protein staining per cell was measured using the CAS-200 image analysis system and expressed relative to the amount of HER-2/neu protein of calibration cells of the SKBR3 cell line which are known to have amplification of the HER-2/neu gene and overexpression of the HER-2/neu protein. There was a significant correlation between degree of HER-2/neu protein overexpression and DNA-hyperdiploidy (P less than 0.01, chi 2 test). No significant correlation could be demonstrated between degree of HER-2/neu overexpression and tumor size, lymph node status, number of positive nodes or morphometric features. There was in general a good concordance (r = 0.83) in HER-2/neu expression values between fresh and paraffin-embedded material. Pairwise comparison of the two series (Wilcoxon signed ranks test) revealed no significant differences, indicating that there were no systematic differences between HER-2/neu assessments in fresh and paraffin material. When analysing the HER-2/neu expression values according to thresholds used earlier for overexpression, comparable results for fresh and paraffin material were obtained for most cases. In the fresh and paraffin material a different staining pattern was observed (more membrane staining in the fresh material in contrast to a more diffuse staining pattern in the paraffin material). It was concluded that both fresh-frozen and paraffin-embedded, formalin-fixed material is suitable for assessment of HER-2/neu protein overexpression by image analysis and provides comparable HER-2/neu expression values in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Quantitation of HER-2/neu oncoprotein overexpression in invasive breast cancer by image analysis: a study comparing fresh and paraffin-embedded material. 167 45

c-erbB-2 protein over-expression was studied immunohistochemically in 319 paraffin-embedded breast carcinomas representing 89% of all breast-cancer cases operated in the Tampere University Hospital between 1977 and 1981. The immunohistochemical evaluation of c-erbB-2 was optimized using protease pre-treatment and verified using antibodies for both the external and the internal domains of the protein. c-erbB-2 over-expression was found in 72 (23%) of the 319 cases and was associated with high histological and nuclear grade (p less than 0.0001), DNA aneuploidy (p = 0.003), high tumor S-phase fraction (p less than 0.0001), and lack of estrogen (p less than 0.0001) and progesterone (p = 0.03) receptors. Overall, breast-cancer patients with c-erbB-2 over-expression had about 2.2-fold relative risk (RR) of death (p less than 0.001) as compared with those without over-expression. According to a multivariate analysis, c-erbB-2 over-expression was an independent prognostic factor in the whole material as well as in the node-negative sub-set. In node-negative breast-cancer tumor size, S-phase and c-erbB-2 status defined a large patient group with only 4% 5-year and 15% 10-year mortality rate without adjuvant therapy. In comparison with c-erbB-2-negative tumors, those with over-expression of this gene metastasized 3 times more often (p = 0.0002) to the lungs, liver and brain and 3 times less often to the bone. Our findings suggest that the prognostic value of c-erbB-2 over-expression may be related not only to increased cell proliferation rate but also to a distinctive pattern of metastasis.
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PMID:Association of c-erbB-2 protein over-expression with high rate of cell proliferation, increased risk of visceral metastasis and poor long-term survival in breast cancer. 168 77

The significance of c-erbB-2 protein expression was immunohistochemically investigated in 32 patients with stage III breast cancer with regard to area, shape factor and DNA content of cancer cell nuclei. Thirty-one percent of the tumors showed c-erbB-2-positive cell membrane staining (10 out of 32 cases), and the cancer cells of the c-erbB-2-positive tumors had larger and more irregular nuclei with an increased DNA content. All patients with c-erbB-2 protein-positive tumors died of the disease within six years of their mastectomy. It can be concluded that positive immunohistochemical staining of c-erbB-2 protein indicates an aggressive biological behavior of the cancer cells as well as a poor prognosis in patients with stage III breast cancer.
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PMID:Significance of immunohistochemically detected c-erbB-2 protein expression in stage III breast cancer, with reference to nuclear deformity, DNA content and prognosis. 168 19


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