Significance of TYMS and ERCC1 Gene Polymorphism in Peripheral Venous Blood in Evaluating the Chemotherapeutic Effect on Patients with Gastroenteric Tumor Patients

Objective To investigate the significance of TYMS and ERCC1 gene polymorphism in peripheral venous blood in evaluating chemotherapeutic effect on outcomes of patients with gastroenteric tumor. Methods Experimental groups: (1)Specimens of patients with non-chemotherapy groups: peripheral blood group and tumor tissue group. (2)Specimens of patients with chemotherapy groups: effective chemotherapy group and ineffective group. The genotypes of TYMS and ERCC1 in peripheral blood and tumor tissue were detected by PCR and PCR-RFLP. Results In peripheral blood and tumor tissues of patients with nonchemotherapy, the detection rates of 3R/3R, (2R/2R, 2R/3R) genotypes of TYMS were 72.09% and 27.91% (P<0.01), those of C/C, (T/T, C/T) genotypes of ERCC1 were 81.39% and 18.61% (P<0.01). The detection rates of 3R/3R, (2R/2R, 2R/3R) genotypes of TYMS in patients with chemotherapy were 65.79% and 34.21%; those of C/C, (T/T, C/T) genotypes of ERCC1 were 63.16% and 36.84%. Chemotherapy response rates of TYMS genotype carriers were 18% and 57.69%; those of ERCC1 were 47.91% and 3.57%. Genotypes of TYMS and ERCC1 had correlation with chemotherapy response rate (P<0.01). Chemotherapy response rates between the genotypes were different(P<0.01). Conclusion Tumor tissues could be replaced by peripheral blood sample in detecting TYMS and ERCC1 polymorphism which could be used to evaluate the efficacy of 5-Fu and platinum drugs.