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)

Administration of 6-nitro-1,3,8-trichlorodibenzofuran (6-NCDF) caused a dose- and time-dependent increase in uterine wet weight and cytosolic and nuclear estrogen receptor (ER) and progesterone receptor (PR) levels in immature female Sprague-Dawley rats. These estrogenic effects persisted for up to 96 or 144 hr after initial administration of 6-NCDF and could be observed at a dose as low as 2 mumol/kg. In contrast, 6-NCDF (25 mumol/kg) did not increase rat uterine peroxidase activity or epidermal growth factor (EGF) receptor binding activity. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), which exhibits a broad spectrum of antiestrogenic effects in the female rat uterus, inhibited the 17 beta-estradiol-induced increase in uterine wet weights, cytosolic and nuclear ER and PR levels, peroxidase activity, and EGF receptor binding activity. In contrast, 2,3,7,8-TCDD inhibited the uterotropic effects caused by 6-NCDF but did not affect the 6-NCDF-induced uterine ER and PR levels. 6-NCDF is a weak inducer of hepatic microsomal ethoxyresorufin O-deethylase activity and competitively binds to the aryl hydrocarbon (Ah) receptor but not the PR or ER. Thus both 6-NCDF and 2,3,7,8-TCDD, two ligands which bind to the Ah receptor, exhibit both partial estrogenic and antiestrogenic properties and serve as useful models for delineating the complex biochemical interactions between the ER and Ah receptor signal transduction pathways.
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PMID:The effect of 6-nitro-1,3,8-trichlorodibenzofuran as a partial estrogen in the female rat uterus. 131 94

We have purified and characterized a novel 30-kDa glycoprotein (gp30) with TGF alpha-like properties secreted from the estrogen receptor negative breast cancer cell line MDA-MB-231. This factor was immunoprecipitated by an anti-TGF alpha polyclonal antibody and also had TGF alpha-like biological activity, as assayed by EGF radioreceptor assay and anchorage-independent assays. In addition, the novel growth factor stimulated phosphorylation of the EGF receptor and erbB-2 receptor. However, the novel growth factor, unlike EGF and TGF alpha, bound to heparin-Sepharose. Purification of gp30 was obtained to apparent homogeneity by heparin affinity chromatography and subsequent reversed-phase chromatography. Tunicamycin treatment in vivo or N-glycanase deglycosylation in vitro revealed a putative precursor of approximately 22 kDa molecular mass in contrast to the "normal" 16-kDa precursor species for TGF alpha. In vitro translation of total mRNA from MDA-MB-231 cells confirmed the size of the putative precursor. Biochemical characterization of gp30 was begun by V8 protease digestion of the deglycosylated polypeptide and the translated products. Peptide mapping of V8-digested, immunoprecipitated material suggests that the amino acid sequence of this unique protein is distinct from mature TGF alpha and not the result of a posttranslational modification of the precursor. We conclude that this TGF alpha-like (gp30) polypeptide is a novel growth factor with agonistic activity for both EGF and erbB-2 receptors.
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PMID:Purification and characterization of a novel growth factor from human breast cancer cells. 132 10

HER-2/neu oncogene protein, epidermal growth factor receptor, progesterone receptor, and estrogen receptor were examined immunohistochemically in specimens of normal and neoplastic endometrium. Tissues obtained at the time of hysterectomy were snap-frozen at liquid nitrogen temperature and serially sectioned at 4 microns. Normal endometrial epithelial cells stained with anti-epidermal growth factor receptor and anti-HER-2/neu with intensities graded from 0 to 3+. Of the 49 endometrial malignancies studied, seven (14%) contained tissue exhibiting HER-2/neu staining in excess (4+) of any of the normal tissues or the other 42 cancer specimens. Expression of both HER-2/neu and steroid receptors was heterogeneous within these seven tumors. To examine this heterogeneity more closely, sections of these and other tumors were double-stained for HER-2/neu and progesterone receptor. It was found that the cells exhibiting 4+ HER-2/neu staining were progesterone receptor-negative. Conversely, cells that were progesterone receptor-positive within the same specimen exhibited HER-2/neu immunostaining equal to or less than 3+. All specimens containing 4+ HER-2/neu tissue were graded 1 or 2 adenocarcinomas, stage I. Thus, there is an inverse relationship between overexpression of HER-2/neu and progesterone receptor in endometrial cancer. On the other hand, overexpression of HER-2/neu in endometrial cancer does not seem to be related to loss of other differentiated characteristics. The prognostic value of these observations awaits continued study.
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PMID:Immunohistochemical study of HER-2/neu, epidermal growth factor receptor, and steroid receptor expression in normal and malignant endometrium. 134 72

c-myc, c-erbB-2, and Ki-67 expression was examined by immunohistochemistry in 11 normal breast tissues and 42 invasive and 14 noninvasive breast carcinomas. The c-myc product was detected in all breast carcinoma specimens and in 7 of 11 normal breast tissues. Invasive tumors stained more frequently with the anti-myc monoclonal antibody than did noninvasive tumors, while the level of expression in normal breast tissue was much less than that in breast cancer. Membrane staining of the c-erbB-2 protein was demonstrated in 29% (4 of 14) of noninvasive ductal carcinomas and in 45% (19 of 42) of invasive breast carcinomas. None of the 11 normal breast tissue samples was positive. The mean value of Ki-67-positive cells was 0.91 +/- 0.31% for normal breast tissue, 4.57 +/- 1.36% for noninvasive ductal carcinoma, and 12.76 +/- 2.18% for invasive breast cancer. In 42 invasive breast carcinomas, the expression of c-myc, c-erbB-2, and Ki-67 proliferation marker were compared with lymph node status, estrogen receptor status, progesterone receptor status, and age of patients at diagnosis. c-erbB-2 overexpression and Ki-67 overexpression were identified as the only factors associated with lymph node status. We concluded that they might be additional prognostic factors for breast carcinoma.
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PMID:c-myc, c-erbB-2, and Ki-67 expression in normal breast tissue and in invasive and noninvasive breast carcinoma. 134 67

Amplification or increased expression of the c-erbB-2 gene has previously been reported to be a prognostic marker for breast cancer. Gene amplification is usually measured by Southern blotting, whereas increased protein expression is usually detected by immunocytochemistry. We measured c-erbB-2 protein with an enzyme-linked immunosorbent assay (ELISA). High concentrations of oncoprotein were found in 25 of 161 (16%) primary breast cancers and in 3 of 6 (50%) breast cancer metastases. High concentrations were not found in normal breast tissue or benign breast tumors. In the primary cancers, high concentrations of c-erbB-2 protein were found more frequently (a) in estrogen receptor-negative tumors than in estrogen receptor-positive tumors, (b) in progesterone receptor-negative tumors than in progesterone-positive tumors, and (c) in axillary node-positive cancers than in node-negative cancers. Patients with tumors containing high amounts of the c-erbB-2 protein had a significantly shorter (P less than 0.001) disease-free interval and overall survival rate than did patients with low amounts. We conclude that assay of c-erbB-2 protein by ELISA is simple, rapid, and quantitative and offers important prognostic information in breast cancer.
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PMID:Enzyme-linked immunosorbent assay of c-erbB-2 oncoprotein in breast cancer. 135 9

Using permanent-section immunohistochemistry, we investigated the role of HER-2/neu in the development and progression of human breast cancer by measuring its overexpression in a series of hyperplastic (n = 30), dysplastic (n = 15), and malignant neoplastic (n = 708) lesions of ductal epithelium and by evaluating the relationships between overexpression and clinicopathologic features known to have prognostic significance in these lesions. The neoplasms included pure ductal carcinoma in situ (DCIS; n = 59) and infiltrating ductal carcinoma (IDC; n = 649). The latter were all node negative and stratified into IDC combined (n = 237) or not combined (n = 412) with a "significant amount" of DCIS (defined as DCIS greater than or equal to 10% of total tumor cellularity). Overexpression of HER-2/neu was not observed in any of the hyperplastic or dysplastic lesions. In contrast, it was present in 56% of pure DCIS and in 77% of the comedo subtype of this group. Only 15% of IDC overexpressed HER-2/neu. However, the rate of overexpression was significantly higher in the subset of IDC combined with DCIS compared with the subset of IDC not combined with DCIS (22% v 11%, respectively; P less than .0001). These results are consistent with the hypothesis that HER-2/neu plays a more important role in initiation than in progression of ductal carcinomas. They also suggest that overexpression decreases within individual tumors as they evolve from in situ to increasingly invasive lesions or, alternatively, that many invasive carcinomas arise de novo (ie, without progressing through a significant in situ stage) by mechanisms not involving HER-2/neu. In addition, overexpression of HER-2/neu was associated with several poor prognostic features (younger patient age, premenopause, negative estrogen receptor status, negative progesterone receptor status, and high nuclear grade) in the subset of IDC combined with DCIS. With one exception (negative estrogen receptor status) these associations were lost in IDC not combined with DCIS, also suggesting that the role of HER-2/neu changes during the progression of human breast cancer.
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PMID:Overexpression of HER-2/neu and its relationship with other prognostic factors change during the progression of in situ to invasive breast cancer. 135 64

Expression of the c-erbB-2 (neu, HER-2) oncogene is found to be subjected to hormonal and developmental regulation in normal as well as neoplastic mammary cells. We have previously reported that estrogens inhibit c-erbB-2 expression at both the mRNA and protein level in estrogen receptor (ER)-positive, but not in ER-negative, breast cancer cell lines. Reversion of c-erbB-2 inhibition is seen with tamoxifen. The effect on c-erbB-2 expression of several other hormones and factors, which influence mammary cell growth and differentiation, has been studied. Our observations indicate that, in normal and neoplastic mammary cells, c-erbB-2 expression is inversely related to cell proliferation. While estrogens, anti-estrogens and cAMP clearly regulate c-erbB-2 mRNA levels, epidermal growth factor dramatically decreases the c-erbB-2 protein without affecting the level of c-erbB-2 mRNA. Therefore, different signals converging in terms of cell proliferation regulate c-erbB-2 expression by different molecular mechanisms.
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PMID:Hormonal regulation of c-erbB-2 oncogene expression in breast cancer cells. 135 14

Expression of the c-erbB-2 oncoprotein (ErbB-2) and the nm23 anti-metastatic gene product (nucleoside diphosphate [NDP] kinase) was examined in the intraductal and invasive components of 63 fresh human breast cancer tissues. The expression of estrogen receptor (ER) as a marker of hormone dependency and the Ki-67 protein as a proliferative cell marker was also examined. ErbB-2 and ER were positive in 77.8% (28/36) and 64.7% (22/34) of the intraductal components, and in 43.6% (27/62) and 57.1% (36/63) of the invasive components, respectively. NDP kinase was positive in 58% (18/31) of intraductal, and in 30.9% (17/55) of invasive areas. The average Ki-67-positive cell rates were 5.9% in the intraductal, and 10.7% in the invasive components. Thus, the cells within the intraductal component of breast cancer appear to have different characteristics from the invasive component, not only in markers of proliferative ability, but also in the expression of oncogenes and hormone receptors.
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PMID:Estrogen receptor, c-erbB-2 and nm23/NDP kinase expression in the intraductal and invasive components of human breast cancers. 135 59

Biologic properties of breast cancer in men that might reflect alterations in pathogenesis from the disease in women were examined. We studied 22 tumors from males, 18 invasive carcinomas, three of which were papillary, and three in situ tumors of which one was papillary, and one papilloma. Our data support the previously reported high incidence of papillary carcinoma in men. Estrogen receptor status and the expression of cancer-associated antigens recognized by antibodies DF3, B73.2, SP-1, and c-erbB-2 were compared to matched tumors from females. Immunocytochemistry was performed on formalin-fixed, paraffin-embedded sections using standard avidin-biotin techniques; anti-PSA was used to exclude the possibility of metatastic prostate cancer, and 12 cases of gynecomastia were included as nonmalignant controls. The incidence of estrogen receptor positivity was higher in tumors from males (73%) than from females (54%), as has been reported previously. The range of expression of all breast cancer antigens tested in male tumors was similar to that observed in females, but some interesting differences were noted. With the exception of the anti-mucin DF3, all the antibodies reacted only with neoplastic tissues. Expression of the oncoprotein c-erbB-2 was lower (17%) in males than in females (33%), despite the preponderance in men of the large-cell type carcinomas that have been associated with c-erbB-2 expression. Unexpectedly, the pregnancy-associated hormone detected by SP-1 was expressed in 33% of tumors from males and, in contrast to females, was found in less differentiated tumors.
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PMID:Immunocytochemical characterization of male breast cancer. 136 97

A 94 year old man with an invasive ductal carcinoma of the breast (T4N2M1, stage IV), underwent a modified radical mastectomy to improve his quality of life. The estrogen receptor status of both the breast tumor and the metastatic axillar lymph nodes was high. Immunohistochemical staining for epidermal growth factor, epidermal growth factor receptor, or c-erbB-2 protein was negative. The patient received only tamoxifen continuously for 3 months, and later apparently showed a complete remission. Therefore, in advanced male breast cancer with a high estrogen receptor status, operation in conjunction with hormone therapy may lead to a favorable result in some cases.
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PMID:A 94 year old male stage IV breast cancer patient showing complete remission under tamoxifen treatment after operation. 151 97


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