Prevalence of K-RAS mutations and CA125 tumor marker in patients with ovarian carcinoma

BACKGROUND: Ovarian carcinoma is one of the leading causes of cancer-related death among females. K-ras codon 12 mutations are commonly occurring mutations in different types of cancers and leads to resistance against anti-EGFR therapeutics. Hence, determination of mutations in k-ras gene is crucial for predicting response to anti-EGFR therapies. This study aimed to evaluate the prevalence of k-ras gene mutations and CA125 tumor marker in patients with ovarian carcinoma in Tabriz city. METHODS: Genomic DNA was extracted from 67 tissues pertained to women with ovarian carcinoma. Mutations in codon 12 and 13 of k-ras gene were analyzed by Nested PCR and RFLP methods. Titer of CA125 tumor marker was determined by ELISA. RESULTS: Among the 67 patients, 7 patients (10.4%) had mutation in k-ras codon 12 while none of them had mutation in k-ras codon 13. Based on the results, the frequency of various genotypes were 89.55%, 10.44%, and 0%, for GG, GA, and AA alleles, respectively. The p-value for stage I and Grade I tumors were 0.022 and 0.04, respectively, indicating a statistically significant correlation between codon 12 mutation and stage I and Grade I tumors. Furthermore, we found significant correlations among CA125 tumor marker titers and histological grade (p<0.000) and stage (p<0.000). The mean serum CA125 tumor marker levels in malignant carcinomas were 499.84 U/ml. CONCLUSION: The results in this study indicated high prevalence of k-ras codon 12 mutations and high titer of CA125 tumor marker in patients with ovarian carcinoma in the study region.