Genetic polymorphisms and treatment response in advanced non-small cell lung cancer

Background: Genetic polymorphisms involved in DNA repair and apoptosis are suspected to influence patient response to cancer treatment. To evaluate the effect of genetic variations on chemotherapy and/or radiotherapy, we genotyped four single nucleotide polymorphisms (SNPs) in ATM (A60G), ERCC1 (Asn118Asn), APE1 (Asn148Glu), and iASPP (A67T), and examined their associations with treatment response among patients with advanced non-small cell lung cancer (NSCLC). Methods: Included in the study were 230 patients diagnosed with inoperable advanced NSCLC. Of these patients, 76 received platinum-based chemotherapy, 125 received chemotherapy plus radiation, and 29 received radiotherapy only. The SNPs were genotyped using the TaqMan methods. Results: Among the patients who received chemotherapy only, ERCC1 (Asn118Asn) genotype was significantly associated with treatment response. Patients with either one or two T alleles (T/T+C/T) at Asn118Asn were more likely not to respond to platinum-based chemotherapy compared to those without the T allele (OR=4.10, 95% Cl: 1.31-12.85). For patients who were treated with both chemotherapy and radiotherapy, treatment response seemed to differ substantially between patients with different genotypes of iASPP (A67T). Patients carrying an A allele (A/T + A/A) at A67T were more likely to respond to combined chemotherapy and radiotherapy compared to those not carrying the A allele (OR = 0.25, 95% CI: 0.08-0.74). An association with treatment response was also suggested for the selected polymorphism in APE1, but no association was found for the ATM polymorphism. Conclusion: We found that SNPs in ERCC1 and iASPP were associated with response to chemotherapy or combined chemotherapy and radiotherapy in NSCLC patients. These findings support the notion that genetic variations related to DNA repair or apoptosis may affect the effect of chemotherapy or radiation on NSCLC. (c) 2006 Elsevier Ireland Ltd. All rights reserved.