ABSTRACT
To investigate the role of H-fas oncogene in the early stages of human breast carcinogenesis. Methods Thirty cases of human breast cancer, 36 epithelial hyperplasia of usual type and 31 atypical hyperplasia were employed to detect H-ras gene codon 12 mutations by PCR-RFLP and PCR-SSCP assays, and to detect the expression of H-ras protein by immunohistochemistry method. ResultsExpression of H-ras protein were found in 73.3 % (22/30) of breast cancer and 48.4 % (15/31 ) of atypical hyperplasia. No H-ras protein expression was observed in hyperplasia of usual type. All tested sarnples of breast cancer and hyperplsia showed no mutations of H-ras gene codon 12. ConclusionOverexpression of H-ras protein is involved in early stages of breast carcinogenesis, but mutations of H-ras gene codon 12 is rarely present in the stage.