RESUMO
To detect the expression levels of the lethal-7 (let-7) and K-ras genes in non-small cell lung cancer (NSCLC) and investigate their significance, the expression of let-7 and K-ras was determined in cancerous tissues and pericancerous normal tissues of 31 NSCLC patients using reverse transcription-polymerase chain reaction. Our results using 31 NSCLC patient samples showed that 67.74% had a low let-7 expression (P<0.05), 64.52% had a high K-ras expression (P<0.05), and a significant correlation was observed between let-7 and K-ras gene expression (r=-0.6336) in tumor tissues. Patients with a low let-7 expression had a significantly shorter survival than those with a moderate let-7 expression (P<0.05). Patients with a high K-ras expression also had a significantly shorter survival than those with a moderate K-ras expression (P<0.05). In conclusion, a low expression of let-7 and a high expression of K-ras are correlated with the pathogenesis and prognosis of NSCLC.
