Polymorphic tandem repeats in the thymidylate synthase gene is associated with its protein expression in human gastrointestinal cancers

摘要: Background. Thymidylate synthase (TS) is a target enzyme of 5-fluorouracil (5-FU), and the TS gene has polymorphic tandem repeated sequence in 5'-untranslated region. We investigated polymorphism on repeat length its relation to number 5-fluoro-dUMP (FdUMP) binding sites human gastrointestinal cancers. Materials Methods. Seventy adenocarcinoma samples were used. Twenty-one patients received UFT® 49 no treatment before surgery. Tandem was determined by PCR amplification genomic DNA. The FdUMP measured 3 H-FdUMP assay. Results. Double- (2R) triple-repeated (3R) sequences found cancer tissues. Three genotypes found: 2R/2R (n = 3), 2R/3R 16) 3R/3R 51). free level for genotype significantly higher than that (+) group. Similar genotype-dependent difference observed (-) Conclusions. Our results suggest link between protein expression. This might offer an advantage selection receive 5-FU-based chemotherapy.