The Relevance of Common K-RAS Gene Mutations and K-RAS mRNA Expression with Clinicopathological Findings and Survival in Breast Cancer

INTRODUCTION: Studies have shown the role of mutation and gene expression of K-RAS in luminal breast cancer. In the current study, the status of common K-RAS mutations and mRNA expression in breast cancer were investigated. The aim of this research was determining the relationship of these molecular finding with clinicopathological features and 5 year overall survival. MATERIAL AND METHODS: In this case control study, we examined tumor tissue obtained from patients who had breast surgery which their paraffin tissue samples were available in the pathology department. Samples who had codon 12 and 13 mutations in exon 2 of K-RAS gene were considered as case group and tumor tissues without these mutations were considered as control group. The expression of K-RAS mRNA was explored by real-time polymerase chain reaction (RT-PCR) and the results were reviewed with clinicopathological features and survival of patients. RESULTS: The results of the present study showed that 14% and 10% of patients had K-RAS mutations in codons 12 and 13, respectively. There was a significant relationship between K-RAS mutations with T staging and PR positivity in tumors. Five years overall survival was 8% in case group compare to control group who had 69% 5y OS. Furthermore, K-RAS mRNA expression had a significant relationship with T and N staging and 5 year survival. In conclusion, it seems that two molecular markers of mutation and K-RAS gene expression may be used simultaneously to estimate the prognosis of breast cancer. CONCLUSION: It seems that two molecular markers of mutation and K-RAS gene expression may be used simultaneously to estimate the prognosis of breast cancer.