原发性胃肠恶性肿瘤胸苷酸合成酶增强子的多态性

目的　检测原发性胃癌、结直肠癌胸苷酸合成酶 (TS)启动基因增强子区段 (TSER)的多态性。方法　采用多聚酶链式反应 (PCR)技术检测 16 0例原发性胃肠恶性肿瘤患者 (胃癌、结直肠癌各 80例 )肿瘤原发灶TSER的表达 ,并测定其DNA序列。结果　 12例表现为双串联重复系列纯合子 ( 2R/ 2R) ,10 9例为三串联重复系列纯合子 ( 3R/ 3R) ,39例为双串联和三串联杂合子( 2R/ 3R) ,而且胃癌与结直肠癌TSER表达差异无显著性 (P >0 .0 5 )。结论　胃肠恶性肿瘤TSER存在多态性 ,表现为纯合子 2R/ 2R、3R/ 3R及两者的杂合子 2R/ 3R ,其中以纯合子 3R/ 3R为主。

Polymorphism of the thymidylate synthase promoter enhancer in primary gastrointestinal cancer

Objective To detect the polymorphism in t he thymidylate synthase promoter enhancer region (TSER) in primary gastrointesti nal cancer.Methods PCR was used to detect TSER in primary foci in 160 cases of primary gastrointestinal carcinoma and DNA sequence was an alyzed by ABI PRISM 310 gene auto-analyzer.Results In 16 0 cases,12 were homozygous with double tandem repeats (2R/2R),109 were homozygo us with triple tandem repeats (3R/3R) and 39 were heterozygous with both alleles (2R/3R).There was no statistically significant difference in TSER genotype bet ween gastric carcinoma and colorectal cancer.Conclusion T here are three genotypes of TSER in primary gastrointestinal carcinoma,homozygo us for 2R/2R,3R/3R and heterozygous with both alleles 2R/3R.3R/3R is the predo minant genotype.