BRCA1 deficiency is also associated with significantly increased expression levels of several protooncogenes, including c-Fos, Ha-Ras, and c-Myc, with a higher expression in tumors, while premalignant mammary epithelial cells displayed an intermediate state between tumors and controls.
Alterations of the p53 tumor suppressor gene and its association with activation of the c-K-ras-2 protooncogene in premalignant and malignant lesions of the human uterine endometrium.
The results of this study indicates no detectable mutations in the 12th codon of the first exon of the Ki-ras gene in any premalignant or malignant melanocytic lesion examined.
Significant elevation of Ha-ras, Ki-ras, and myc oncogene expression were found both in premalignant and malignant tumours as compared to the normal tissue.