ABSTRACT
Objective@#To investigate the associations between genetic variations of DNA polymerase kappa (POLK) and treatment response to platinum-based chemotherapy of small cell lung cancer (SCLC), and to analyze the influencing factors on survival.@*Methods@#Five haplotype-tagging single nucleotide polymorphisms (htSNPs) of POLK were genotyped by Sequenom MassARRAY methods in 1 030 SCLC patients who received platinum-based chemotherapy, and had different response and survival time. The associations between SNPs and treatment response were analyzed by computing the odds ratios (ORs) and 95% confidence intervals (CIs) from logistic regression model. Cox regression was used for survival analysis between SNPs and overall survival by computing the hazard ratios (HRs) and 95% CIs.@*Results@#Among 1 030 cases, 558 (54.2%) cases received cis-platinum and etoposide treatment while others treated with carboplatin and etoposide. Seven hundred and eighty eight patients were chemotherapy responders in the study with a response rate of 76.5%. The median follow-up time of these patients was 22.0 months. Patients were followed up to get their survival information. The median survival time of these patients was 22.5 months. Six hundred and seventy three patients (65.3%) had died by the last date of follow-up to get their survival information (Dec 21, 2017). Five htSNPs of POLK were not associated with the chemotherapy response of SCLC patients who received platinum-based chemotherapy (all P>0.05). Multivariate Cox proportional hazards regression model analysis showed that, rs73120833 of POLK was significantly associated with the overall survival (OS) of SCLC patients, compared with POLK rs73120833 T allele, C allele can prolong OS (adjusted HR=0.87, 95% CI=0.77-0.97, P=0.021). The remaining 4 SNPS, including rs10077427, rs3756558, rs4549504 and rs5744545, were not significantly associated with overall survival. Age≤56, KPS> 80, limited-stage, chemotherapy response and radiation therapy can remarkably prolong OS (all P<0.05).@*Conclusion@#These results suggest that POLK genetic polymorphism rs73120833 plays an important role on the prognosis of SCLC patients, which can be potential genetic biomarker for SCLC personalized treatment.
ABSTRACT
PURPOSE: Mismatch repair (MMR) deficiency plays a critical role in rectal cancer. This study aimed to explore the associations between genetic variations in seven MMR genes and adverse events (AEs) and survival of patients with rectal cancer treated with postoperative chemoradiotherapy (CRT). MATERIALS AND METHODS: Fifty single nucleotide polymorphisms in seven MMR (MLH1, MLH3, MSH2, MSH3, MSH6, PMS1 and PMS2) genes were genotyped by Sequenom MassARRAY method in 365 patients with locally advanced rectal cancer receiving postoperative CRT. The associations between genotypes and AEs were measured by odds ratios and 95% confidence intervals (CIs) by unconditional logistic regression model. The associations between genetic variations and survival were computed by the hazard ratios and 95% CIs by Cox proportional regression model. RESULTS: The most common grade ≥ 2 AEs in those 365 patients, in decreasing order, were diarrhea (44.1%), leukopenia (29.6%), and dermatitis (18.9%). Except 38 cases missing, 61 patients (18.7%) died during the follow-up period. We found MSH3 rs12513549, rs33013 and rs6151627 significantly associated with the risk of grade ≥ 2 diarrhea. PMS1 rs1233255 had an impact on the occurrence of grade ≥2 dermatitis. Meanwhile, PMS1 rs4920657, rs5743030, and rs5743100 were associated with overall survival (OS) time of rectal cancer. CONCLUSION: These results suggest that MSH3 and PMS1 polymorphisms may play important roles in AEs prediction and prognosis of rectal cancer patients receiving postoperative CRT, which can be potential genetic biomarkers for rectal cancer personalized treatment.