Growth speed plays a greater role than MMR status in determining the long-term survival of colon carcinoma cells treated with 5-FU

Introduction: Whether mutations in the hMLH1 gene, which is a component of the mismatch repair system, increase or decrease the sensitivity of colon carcinomas to 5-fluorouracil (5-FU) is a matter of controversy. We investigated the effect of growth speed and MMR status on long term survival of colon carcinoma cells after 5-FU treatment. Materials and methods: We used the HCT116 cell line which was either transfected with hMLH1 plasmid (MMR+) or with empty vector (MMR-) or the semiisogenic cell pair HCT116Chr3 (MMR+) and HCT116Chr2 (MMR-). MMR- and MMR+ cells were treated with 30µM 5-FU for 48h and clonogenic su…