c-erbB-2 DNA amplification and mRNA expression in human primary breast tumors and its relationship to other prognostic factors.
In order to evaluate the involvement of cerbB-2 oncogene in the etiology and progression of breast cancer, DNA samples from 157 primary human mammary carcinomas were subjected to Southern and dot blot analyses for the presence of c-erbB-2 protooncogene alterations. None of 157 carcinomas analyzed showed c-erbB-2 rearrangement. Amplification of the c-erbB-2 was found in 28.6% (45/157) of the samples. Gene expression could be analyzed in only 97 of these tumors. High levels of c-erbB-2 transcripts were detected in 25.7% (25/97) of the tumor RNA preparations. Although there was a good correlation between c-erbB-2 overexpression and gene amplification, a significant proportion of the tumors showed overexpression in the absence of gene amplification or gene amplification without overexpression. A significant correlation between c-erbB-2 proto-oncogene alterations with the number of positive lymph nodes and tumor necrosis was found, suggesting that c-erbB-2 genetic alterations have a biological importance in the etiology of breast cancer.
Nagai
M A
MA
Departamento de Clinica Medica, Faculdade de Medicina, Universidade de Sao Paulo, Brazil.
Pacheco
M M
MM
Oshima
C T
CT
Brentani
M M
MM
D001943:Breast Neoplasms / Q000235:genetics* / Q000401:mortality; D015342:DNA Probes; D004273:DNA, Neoplasm / Q000235:genetics*; D005260:Female; D005784:Gene Amplification; D015870:Gene Expression; D018734:Genes, erbB-2; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger / Q000235:genetics*
D015342:DNA Probes; D004273:DNA, Neoplasm; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger