The effects of fluorouracil (5-FU) and interferon-gamma (IFN-gamma) on the regulation of thymidylate synthase (TS) gene expression were investigated in the human colon cancer H630 cell line.
For these studies, we used a TS-depleted human colon cancer HCT-C cell that had been transfected with either the human TS cDNA or the Escherichia coli TS gene.
Inhibitors of the enzyme thymidylate synthase (TS), such as the fluoropyrimidines 5-fluorouracil and 5'-fluoro-2'-deoxyuridine (FdUrd) or the antifolates AG337, ZD1694, and BW1843U89, are widely used in the chemotherapy of cancer, particularly cancer of the colon and rectum.
Enzyme prodrug gene therapy: synergistic use of the herpes simplex virus-cellular thymidine kinase/ganciclovir system and thymidylate synthase inhibitors for the treatment of colon cancer.
Cell death due to thymine (dThd) deficiency, associated with the cytotoxic action of 5-fluorouracil in colon cancer, is regulated in thymidylate synthase-deficient (TS(-)) human colon carcinoma cells via the Fas (CD95, APO-1) death receptor.
In vivo transfection experiments revealed that the presence of the selected RNA sequence resulted in a significant increase in the expression of a heterologous luciferase reporter construct in human colon cancer H630 and TS-overexpressing HCT-C:His-TS+ cells, but not in HCT-C18 cells expressing a functionally inactive TS.
Tamoxifen and gonadal steroids inhibit colon cancer growth in association with inhibition of thymidylate synthase, survivin and telomerase expression through estrogen receptor beta mediated system.
TS mRNA expression determined by real-time reverse transcription-PCR correlated with TS protein levels determined by TS immunoblot and immunohistochemistry in cultured colon cancer cell lines and paraffin-embedded primary tumor tissue.
Transfection of TS1058 siRNA into human colon cancer RKO cells resulted in a dose-dependent inhibition of TS expression with an IC(50) value of 10 pM but had no effect on the expression of alpha-tubulin or topoisomerase I. Inhibition of TS expression by TS1058 was maximal at 48 h and remained suppressed for up to 5 days.
TYMS and PGK1, as well as their epitope peptides, might be appropriate target molecules for specific immunotherapy of HLA-A2(+) colon cancer patients because of the positive role of TYMS and PGK1 in chemoresistance (5-fluorouracil) and angiogenesis of tumor cells, respectively.
We investigated on colon cancer cells the effect of geraniol on thymidylate synthase and thymidine kinase expression, two enzymes related to 5-fluorouracil cytotoxicity.
Polymorphism of the thymidylate synthase gene and thymidylate synthase levels in colon cancer cell lines and different tissues of colorectal cancer patients.
Recently, it has become apparent that rTSb overexpression can cause the downregulation of TS protein in a colon cancer cell line through the production of > or = 1 previously unknown signaling molecules.
In this study, a comprehensive gene expression analysis at the levels of both transcriptional and post-transcriptional regulation was conducted to identify response markers using human genome array with TS-depleted human colon cancer HCT-C18 (TS-) cells and HCT-C18 (TS+) cells stably transfected with the human TS cDNA expression plasmid.
MSI status and TS expression were unrelated and TS was not prognostic, suggesting that TS levels cannot explain therapeutic resistance to 5-FU reported in MSI-H colon cancers.