P2.01-58 Detection of Kras Mutation from Urine of Indonesian Lung Cancer Patients

Abstract

KRAS is one of the most frequently mutated genes in Lung adenocarcinomas and has correlation with smoking history. The prevalence of KRAS mutated genes in Indonesian Lung cancer patients may be very high, because Indonesia is one of country with highest cigarettes consumption in the world. Urine is a potential source of biomarker analysis. In this study we identified KRAS mutation in urine sample from lung adenocarcinoma patients. Seventy four urine samples from naive Lung adenocarcinoma patients were collected and extracted to get DNA as material of biomarker analysis. Analysis of KRAS mutation exon 2 was focused on codon 12 and 13 using Restriction Fragment Length Polymorphism (RFLP) and Sanger Sequencing methods. Analytical sensitivity of those methods was evaluated using dilution of DNA from mutant and normal KRAS cell lines. Gender and smoking history of the patients in correspondence with KRAS mutation were also evaluated. The analytical sensitivity of the methods was at least 3.125% of mutant DNA using RFLP and at least 25% of mutant DNA by Sanger sequencing. KRAS mutation was detected in 15 of 74 urine patients. Eighty percent (12/15) of them are codon 12 mutation and twenty percent (3/15) are codon 13 mutation. In comparison between man and woman, we found that 7 male patients and 5 female patients have KRAS mutation in codon 12. We also found that 71.43% of KRAS mutation was in male patients with smoking history. It is concluded that KRAS mutation was found in urine samples of lung cancer patients and has correlation with smoking history. Urine is a great candidate to be an alternative of lung cancer samples. Comparison using cytological or biopsy samples must be evaluated to determine sensitivity and specificity of urine based KRAS mutation testing.