This meta-analysis suggests that the TSER polymorphism in TS gene but not TS1494del6 polymorphism might be a protective factor for CRC among Caucasian populations.
Thymidylate synthase is associated with risk of colorectal cancer but not with gastric cancer; however, heterozygous SL (2R/3R) polymorphism is associated with risk of gastric cancer; moreover, the 5' tandem repeat polymorphism of thymidylate synthase gene was an independent predictor of the clinical treatment.
Messenger RNA (mRNA) expression of major 5-FU metabolic enzymes, namely thymidylate synthase, dihydropyrimidine dehydrogenase, thymidine phosphorylase (TP), orotate phosphoribosyl transferase, and β-actin (control) was evaluated using the Danenberg Tumor Profile method. mRNA expression and other clinicopathological data were investigated with regard to CRC relapse.
Proximal CRC tumors are characterized by higher TS expression genotypes than distal tumors, and are at significantly greater risk of early recurrence during the first 20 months after surgery.
Results for other variants varied across individual studies; in our meta-analyses we observed some evidence for SHMT 1420C>T (rs1979277) ((odds ratio) OR = 0.85; 95% confidence interval (CI) = 0.73-1.00 for TT v. CC) and TYMS 5' 28 bp repeat (rs34743033) and CRC risk (OR = 0.84; 95% CI = 0.75-0.94 for 2R/3R v. 3R/3R and OR = 0.82; 95% CI = 0.69-0.98 for 2R/2R v. 3R/3R).
Thymidylate synthetase is the major target of 5-fluorouracil (5-FU), which is widely used for the treatment of gastric cancer (GC) and colorectal cancer (CRC).
Using a dominant model for the variant allele, several SNPs were significantly associated with CRC including MTHFD1 rs8003379 (OR = 1.65; 95% CI = 1.00-2.73) and rs17824591 (OR = 1.98; 95% CI = 1.14-3.41) and the TYMSrs2853533 SNP (OR = 1.38; 95% CI = 1.05-1.80).
Danenberg tumor profile method (DTP) was used in order to measure mRNA expression levels of thymidylate synthase (TYMS), dihydropyrimidine dehydrogenase (DPYD), and thymidine phosphorylase (TYMP) from 180 patients with colorectal cancer.
High expression of TYMS and ERCC1 mRNA was associated with better in vitro chemosensitivity to 5-FU and oxaliplatin, respectively, in patients with colorectal cancer.
Thymidylate synthase (TS) expression levels appear to be related to response to 5-fluorouracil-(5-FU)-based chemotherapy in colorectal cancer (CRC) patients.
In this study, TS mRNA expression was examined in primary tumor and normal tissues from 76 patients with high- risk stage II/III colorectal cancer by laser capture microdissection and polymerase chain reaction.
Variants in the dihydropyrimidine dehydrogenase, methylenetetrahydrofolate reductase and thymidylate synthase genes predict early toxicity of 5-fluorouracil in colorectal cancer patients.
The TS genotype of 68 patients with colorectal cancer was determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis in peripheral blood mononuclear cells and tumour tissue.
Chronic exposure of colorectal cancer cells in culture to fluoropyrimidine analogs induces thymidylate synthase and suppresses p53. A molecular explanation for the mechanism of 5-FU resistance.
Based on these data, we investigated whether patient's gender and TS polymorphism exert an interactive effect on the clinical evolution of patients with advanced colorectal cancer (CRC) subjected to 5 fluorouracil (5FU)-based adjuvant chemotherapy.
The impact of thymidylate synthase (TYMS) and UDP-glucoronosyltransferase 1A (UGT1A) germline polymorphisms on the outcome of colorectal cancer (CRC) patients treated with irinotecan plus 5-fluorouracil (irinotecan/5FU) is still controversial.
To address this issue, we studied TSER genotype, TS expression, and activity with specific polymerase chain reaction and activity assays (TS catalytic activity and FdUMP binding) in normal (liver, mucosa) and malignant (primary tumor and liver metastasis) tissues from 83 patients with CRC.
MSI in five reference loci, MMR enzymes (hMSH2, hMSH6, hMLH1 and hPMS2), thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) expression were assessed in paraffin embedded tumor specimens, and associated with outcome in 340 consecutive patients completely resected for colorectal cancer stages II-IV and subsequently receiving adjuvant 5-fluorouracil therapy.