Abstract
BACKGROUND AND OBJECTIVE: It has been proven that the insulin-like growth factor 1 receptor (IGF-1R) gene is an important regulator of many aspects of growth, differentiation, and development. The insulin-like growth factor 2 receptor (IGF-2R) gene is a negative mediator for carcinogenesis. The aim of this study is to investigate the relationship of IGF-1R+1013(G/A) and IGF-2R+1619(G/A) single nucleotide polymorphism (SNP) with platinum-based chemotherapy outcomes in advanced non-small cell lung cancer (NSCLC). METHODS: A total of 132 patients with NSCLC were routinely treated with platinum-based chemotherapy, and their clinical responses were evaluated after four cycles of chemotherapy. IGF-1R+1013(G/A) and IGF-2R+1619(G/A) were genotyped using polymerase chain reaction-restrictive fragment length polymorphism. The relationship between IGF-1R+1013(G/A) and IGF-2R+1619(G/A) genotypes and the clinical benefit rate, as well as the median survival time (MST), was analyzed. RESULTS: No significant association was found between IGF-1R+1013(G/A) and IGF-2R+1619(G/A) polymorphisms with clinical benefit (P>0.05). Further, we found that the two SNPs could not work together (P=0.975). The MST of patients with IGF-1R+1013(G/A) genotypes with A allele (GA+AA) was significantly shorter than that of GG genotype carriers (P=0.017). There was no significant difference in MST in patients with IGF-2R+1619(G/A) A allele (GA+AA) carrier and GG genotype carrier (P=0.575). The two SNPs showed a synergistic effect on MST. Patients who carried a mutant allele A of IGF-1R+1013(G/A) and a mutant allele A of IGF-2R+1619(G/A) had a MST of 12 months, which was significantly shorter than that of patients with other genotypes (P<0.05). Estimation by the Cox proportional hazards model showed that IGF-1R+1013(G/A) polymorphism is an independent prognostic factor (P=0.020), and IGF-1R+1013(G/A) polymorphism in combination with IGF-2R +1619(G/A) polymorphism is an independent prognostic factor in advanced NSCLC (P=0.025). CONCLUSIONS: IGF-1R+1013(G/A) polymorphism alone or in combination with IGF-2R +1619(G/A) polymorphism was associated with the overall survival period in patients with advanced NSCLC after treatment with platin-based chemotherapy, which might be a prognostic factor in platin-treated patients with advanced NSCLC.