Association of CD44 Gene Polymorphism with Survival of NSCLC and Risk of Bone Metastasis

Background: Previous studies have reported CD44 expression influenced the development and progression of tumors. The aim of this study was to investigate whether single-nucleotide polymorphisms (SNPs) of the CD44 gene are as-sociated with survival of non-small cell lung cancer (NSCLC) and occurrence rate of bone metastasis. Material/Methods: A total of 234 patients with NSCLC between 2003 and 2010 were enrolled in this study and 468 healthy per-sons were used as controls. Two polymorphisms, rs13347 and rs187115, in the CD44 gene were genotyped using DNA from blood lymphocytes. For statistical analysis we used the chi-square test, Fisher’s exact test, Kaplan-Meier method, and log-rank test. Results: CD44 gene rs13347 polymorphism was not associated with NSCLC risk. For rs187115, the association with NSCLC risk was observed (P<0.001). Allele G carriers had significantly higher occurrence rates of bone metasta-sis (OR=0.4, 95%CI: 0.20–0.64, P<0.001) and more advanced tumor stage (OR=2.6, 95%CI: 1.50–4.45, P=0.001) compared to carriers of allele A. The survival rates for patients with AA genotype were significantly higher than for patients with the AG+GG genotypes (P<0.001). In multivariate analysis of survival in NSCLC patients, signifi-cant predictors were CD44 gene (AG+GG) (RR=0.48, 95%CI: 0.34–0.68, P<0.001), tumor stage (RR=0.45, 95%CI