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)

The effect of prolonged administration of a rat C-erbB-2/neu (C-erbB-2) antisense oligonucleotide on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and on the labeling and apoptotic indices of gastric cancer was examined in Wistar rats After oral treatment with MNNG for 25 weeks, the rats received intraperitoneal injections of a C-erbB-2 antisense-liposome complex or a sense-liposome complex at a dose of 50 microgram oligonucleotide/kg body weight every other day until the end of the experiment in week 52. In week 52, the incidence of gastric cancers was significantly lover in rats treated with the C-erbB-2 antisense oligonucleotide than in rats treated with the sense oligonucleotide. Administration of the C-erbB-2 antisense oligonucleotide also significantly decreased the bromodeoxyuridine-labeling index and significantly increased the apoptotic index of gastric cancers. The mean cellular fluorescence of gastric antral cells in MNNG-treated rats was positively correlated with the dose of FITC-labeled C-erbB-2 antisense oligonucleotide. Our findings indicate that the antisense oligonucleotide inhibits gastric carcinogenesis through decreased cell proliferation and increased apoptosis induction and suggest that antisense strategies may provide new treatment for gastric cancer.
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PMID:Inhibition by rat C-erbB-2/neu antisense oligonucleotide of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats. 1052 5

Using immunohistochemistry, expression of p53, transforming growth factor-alpha (TGF-alpha), epidermal growth factor receptor (EGFR), c-erbB-2/neu and proliferating cell nuclear antigen (PCNA) was examined in 26 fresh frozen tissue specimens of oropharyngeal squamous cell carcinomas (SCCs). p53 gene mutations were examined by polymerase chain reaction (PCR)/DNA sequencing methods in 22 carcinomas. The findings were examined for correlations with patients' clinicopathological parameters. Expressions of p53 and PCNA were also examined in 21 formalin-fixed corresponding tissues. Of the fresh frozen tissue specimens, 77% (20/26) showed expression and 68% (15/22) showed mutations (substitutions) of the p53, with significant clustering of the mutations in exons 5 (8/22; 36%), 7 (4/22; 18%) and 8 (5/22; 23%). No mutations were found in exon 6. There was a discordance between expression of p53 protein and mutations of the gene. Parallel to expression and mutations of the p53 found in most of the specimens, expression of TGF-alpha, EGFR, c-erbB-2/neu and PCNA was found in 88% (22/25), 92% (23/25), 58% (14/24) and 91% (21/23) of the specimens, respectively. For the formalin-fixed tissue specimens, 62% (13/21) and 90% (19/21) expressed p53 and PCNA, respectively. Examining for correlations with patients' clinicopathological parameters, expression of p53, TGF-alpha, EGFR and c-erB-2/neu seemed to negatively correlate with the increase of the tumour grade. The present work suggests that: (1) lack of negative growth regulation due to inactivation of the p53 gene together with activation of other proto-oncogenes are necessary genetic events in the carcinogenesis of oropharyngeal SCCs; (2) in oropharyngeal SCCs, p53 gene mutations were clustered in exons 5 (codons 130-186), 7 (codons 230-248) and 8 (codons 271-282) which perhaps suggests that tobacco carcinogens probably affect the mutational hot spots of the p53 gene at codons 157, 175, 186, 248, 273 and 282; and (3) fresh frozen and formalin-fixed tissue specimens give similar results when an immunohistochemical method is applied. The importance of p53, TGF-alpha, EGFR, c-erbB-2/neu and PCNA as biomarkers in oropharyngeal SCCs deserves particular attention because it might offer further understanding of the development of these carcinomas.
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PMID:Expression of biomarkers (p53, transforming growth factor alpha, epidermal growth factor receptor, c-erbB-2/neu and the proliferative cell nuclear antigen) in oropharyngeal squamous cell carcinomas. 1062 52

Primary fallopian tube carcinoma is a rare form of female cancer and the genetic basis of its carcinogenesis remains unclear. Eighteen cases of primary fallopian tube adenocarcinoma were studied. Immunohistochemical staining for p53, HER-2/neu and c-myc genes were performed. Overexpression of p53 was detected in 12 cases (67%), HER-2/neu in 16 cases (89%), and c-myc in 11 cases (61%). The potential relevance of overexpression of the three genes with clinicopathological features was examined, but no significant correlation was found. The high incidence of p53, HER-2/neu and c-myc overexpression in fallopian tube adenocarcinoma suggests these genes may play a role in its tumorigenesis.
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PMID:Overexpression of p53 and HER-2/neu and c-myc in primary fallopian tube carcinoma. 1062 73

In gastric cancer, the process of carcinogenesis is thought to occur as a stepwise accumulation of genetic abnormalities. However, the mechanisms of the process of multistage carcinogenesis is still unknown for gastric cancer. Gene abnormalities seen in gastric cancer, including ras, myc, c-erbB-2, met, K-sam and cript are summarized herein. Abnormalities of cancer suppressor genes, including p53, RB and APC are also described. In our studies, the biological malignancy of patients with c-erbB-2 amplification was higher than that of patients without amplification. Moreover, the cases with amplification of c-erbB-2 were found to be highly correlated with distant organ metastasis. However, very little is currently known of the molecular abnormalities leading to gastric cancer. In order to clarify the multiple gene abnormalities in gastric cancer, we used the method of restriction landmark genomic scanning (RLGS). RLGS provides a useful method for genomic analysis of gastric cancer. In the future, new analytical methods that will permit screening of all gene abnormalities at once promise to improve our understanding of the mechanisms of gastric cancer.
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PMID:[Molecular biology in gastric cancer]. 1063 96

We examined risk factors for breast cancer after subdividing cases based on the presence of HER-2/neu oncogene amplification in their tumors. Data were from the Carolina Breast Cancer Study, a population-based, case-control study of 577 invasive breast cancer patients, diagnosed during 1993-1996 and ages 20-74 years, and 790 controls frequency-matched on race and age. Information on breast cancer risk factors was obtained from structured personal interviews. About 20% of paraffin-embedded tissues from the breast cancers of cases were identified as positive for HER-2/neu amplification (HER-2/neu+) by differential PCR. Early age at menarche, higher waist:hip ratio, and family history of breast or ovarian cancer were associated with elevated odds ratios (ORs) for both HER-2/neu+ and HER-2/neu- breast cancers. Breastfeeding for at least 1 year was inversely associated with HER-2/neu+ breast cancer [OR, 0.3; 95% confidence interval (CI), 0.1-0.7] more so than HER-2/neu- breast cancer (OR, 0.8; 95% CI, 0.5-1.2). Most of the remaining risk factors had ORs around 1.0 for both HER-2/neu+ and HER-2/neu- breast cancers, although a few exhibited possible associations with one disease subtype in analyses stratified by menopausal status. These study results suggest that most recognized breast cancer risk factors do not operate through HER-2/neu amplification in breast carcinogenesis. Differential effects of long-term breastfeeding by HER-2/neu amplification status have been observed in earlier studies and are provocative; however, the direction and magnitude of the associations have not been consistent.
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PMID:Risk of breast cancer according to the status of HER-2/neu oncogene amplification. 1066 65

Ovarian cancer remains the leading cause of death from gynecologic malignancy in Western countries. This cancer results from a succession of genetic alterations involving oncogenes and tumor suppressor genes which have a critical role in normal cell growth regulation. Mutations and/or overexpression of three oncogenes, HER-2/neu, c-myc and K-ras, and of the tumor suppressor gene p53, have frequently been observed in sporadic ovarian cancer. In the context of high risk families, the most frequently involved genes are BRCA1 and BRCA2. We review the function of these different proteins, the incidence of mutations in their genes in carcinogenesis and as potential prognostic factors in sporadic and hereditary ovarian cancer.
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PMID:Major oncogenes and tumor suppressor genes involved in epithelial ovarian cancer (review). 1067 91

The purpose of this study was to analyse erbB-1 and erbB-2 oncogenes in non-dysplastic oral leukoplakia to see if we could pinpoint the first steps towards dysplasia and possible carcinogenesis. Fresh biopsy specimens of leukoplakia in 13 patients with no history of oral cancer were examined using the competitive-differential polymerase chain reaction. The mean gene copy numbers of erbB-1 and erbB-2 were calculated from the formula to compare the absolute quantities of reference gene and oncogene from 24 patients who did not have leukoplakia. Healthy mucosa was taken as controls. In eight patients with leukoplakias, the results indicated aberrations of the erbB-1 oncogene, and two patients had gene dosage changes of erbB-2. There were no signs of deletions or amplifications in the controls. These results suggest that aberrations of erbB-1 and erbB-2 are additional markers in premalignant oral lesions at the beginning of the carcinogenic process, and that genetic alterations in histologically non-dysplastic premalignant oral lesions are common.
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PMID:Aberrations of erbB-1 and erbB-2 oncogenes in non-dysplastic leukoplakias of the oral cavity. 1068 11

The neu (c-erbB-2, Her-2) protooncogene is amplified and overexpressed in 20-30% of human breast cancers. Although transgenic mouse models have illustrated the role of Neu in the induction of mammary tumors, Neu expression in these models is driven by a strong viral promoter of questionable relevance to the human disease. To ascertain whether expression of activated Neu under the control of the endogenous promoter in the mammary gland could induce mammary tumors we have generated mice that conditionally express activated Neu under the transcriptional control of the intact endogenous Neu promoter. Expression of oncogenic neu in the mammary gland resulted in accelerated lobulo-alveolar development and formation of focal mammary tumors after a long latency period. However, expression of activated Neu under the normal transcriptional control of the endogenous promoter was not sufficient for the initiation of mammary carcinogenesis. Strikingly, all mammary tumors bear amplified copies (2-22 copies) of the activated neu allele relative to the wild-type allele and express highly elevated levels of neu transcript and protein. Thus, like human erbB-2-positive breast tumors, mammary tumorigenesis in this mouse model requires the amplification and commensurate elevated expression of the neu gene.
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PMID:Amplification of the neu/erbB-2 oncogene in a mouse model of mammary tumorigenesis. 1071 6

We examined a 34-year-old premenopausal woman who had noticed a left-breast lump a month previously. She had no past history of malignancies but had a family history of breast and ovarian cancers. Her mother had suffered from ovarian cancer when aged 47 years and had died of the disease at age 52. The younger two of the patient's four aunts had developed breast cancer when they were 37 and 48 years old. A physical examination showed an ill-defined mass, 1.5 cm in diameter, located in the upper outer quadrant of the patient's left breast. Mammography revealed diffuse microcalcification in both breasts but ultrasonography revealed an irregular tumorous lesion only in the left breast. Aspiration breast cytology revealed adenocarcinoma of the left breast. Modified radical mastectomy of the left breast and excision of a biopsy specimen from the right breast were carried out simultaneously. Histopathologically the left-breast tumor was an atypical medullary carcinoma with cartilaginous metaplasia, of histological grade 3, and the right-breast specimen showed fibrocystic changes with atypical ductal hyperplasia. Estrogen receptors were positive, but progesterone receptor was not detected on the tumor cells, which were immunopositive for nuclear p53 although c-erbB-2 overexpression was not observed. A nonsense germline mutation of the BRCA1 gene (exon5) was detected. The patient has been well since the operation (10 months). These findings may provide useful information about the carcinogenesis and biological behavior of BRCA1-associated breast cancers.
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PMID:Atypical medullary carcinoma of the breast with cartilaginous metaplasia in a patient with a BRCA1 germline mutation. 1077 May 66

17 beta-hydroxysteroid dehydrogenases (17 beta-HSDs) are involved in the interconversion of biologically active and inactive sex steroids and are considered to play important roles in the in situ metabolism of estrogen in various estrogen dependent tissues. 17 beta-HSD type 1 catalyzes primarily the reduction of estrone (E1) to estradiol (E2), whereas 17 beta-HSD type 2 catalyzes primarily the oxidation of E2 to E1. However, the possible biological roles of these estrogen metabolizing isozymes in human breast cancer, especially in carcinogenesis of the human breast, have not been examined in detail. Because of the potential roles of estrogens in the early stages of human breast carcinogenesis, we have examined the immunolocalization of 17 beta-HSD type 1 and type 2 isozymes and estrogen receptor alpha(ER alpha) in both normal human breast tissue and in breast cancers, including ductal carcinoma in situ (DCIS), proliferative disease without atypia (PDWA) or fibrocystic disease and atypical ductal hyperplasia (ADH). We also correlated these findings with clinicopathological findings, Ki67 antigen, progesterone receptor (PR), c-erbB-2, and p53. 17 beta-HSD type 2 immunoreactivity was sporadically detected in non-proliferative or Ki67 negative ductal epithelia of normal breast, but rarely in breast carcinoma cells. 17 beta-HSD type 1 immunoreactivity was detected in 12/22 (54.5%) PDWA cases, 8/26 (30.8%) ADH cases, and 25/40 (62.5%) DCIS cases, respectively. 17 beta-HSD type 1 immunoreactivity was not statistically correlated with the age of the patients, Ki67 labeling index (LI), and PR LI, p-53 and c-erbB-2 immunoreactivity. There was no significant correlation between ER alpha LI and 17 beta-HSD type 1 immunoreactivity. There was a positive correlation between ER alpha and Ki67 LI in PDWA, whereas a negative correlation was detected between ER alpha and Ki67 LI in DCIS. There was no correlation between ER alpha and Ki67 LI in ADH. These results suggest that in human breast epithelial cells, development of ADH and DCIS may be associated with the loss and/or deviation of oestrogen dependent regulation of cell proliferation.
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PMID:17 beta-Hydroxysteroid dehydrogenase type 1 and type 2 in ductal carcinoma in situ and intraductal proliferative lesions of the human breast. 1081 Apr 3


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