ABSTRACT
Objective This study was to determine the role of the Xeroderma pigmentosum group D (XPD) Asp312Asn polymorphism in predicting response to Oxaliplatin based chemotherapies and survival in patients with metastatic colorectal cancer.Methods This study enrolled a total of 106 patients treated with FOLFOX4 (n =72) or XELOX (n =34) regimen.The genotype of XPD Asp312Asn was analyzed by TaqMan probe based real-Time polymerase chain reaction (PCR).Logistic regression was used to predict the response to the treatments.Cox proportion hazards models and Kaplan-Meier method were applied to predict the survival.Results The effective rate of chemotherapy in 106 patients with colorectal cancer was 57.6％ (61/106).There was no significant difference in the distribution of G/G,G/A and A/A genotypes between the two groups (P ＞ 0.05).Multivariate survival analysis showed that the survival time of patients with A/A genotype,carcinoembryonic antigen (CEA) (＞5 ng/ml) and age (＞65 years) was relatively short,with statistical significance (P ＜ 0.05).Conclusions XPD Asp312Asn single nucleic acid polymorphism can be used as a predictor of survival in patients with metastatic colorectal cancer,but it is not associated with oxaliplatin sensitivity and needs further study.
ABSTRACT
Objective To investigate the predictive value of combined analysis on single nucleotide polymorphisms (SNPs) of X-ray cross-complementing1 ( XRCC1 ) gene 194 and 399 codon,xeroderma pigmentosum group D (XPD) gene 312 codon and glutathione S-transferase P1 (GSTP1) gene 105 codon in platinum based chemotherapy.Methods Direct sequencing was performed to detect XRCC1,XPD and GSTP1 genotypes in peripheral blood from 50 cancer patients receiving platinum-based chemotherapy.Genetic polymorphisms of these genes related to sensitivity of platinum were reviewed.Results Favorable genotypes were Arg/Trp and Trp/Trp in XRCC1 194 codon,Arg/Arg in XRCC1 399 codon,Asn/Asn in XPD 312 codon and Val/Val in GSTP1 105 codon.The response rate to chemotherapy was 57.1％,75.0％,60.9％,85.7％ and 87.5％,respectively.The response rate for patients possessing ≥2 favorable genotypes and those possessing 1 or 0 favorable genotype was 78.9％,36.4％ and 0,respectively.Patients possessing ≥2 favorable genotypes demonstrated higher sensitivity to platinum based chemotherapy,compared with those possessing 1 or 0 favorable genotype ( x2 =25.79,P ＜ 0.01 ).Conclusions Combination analysis of genomic polymorphisms of XRCC1,XPD and GSTP1 may be useful in predicting sensitivity of platinum based chemotherapy.