Multiple MTS assay as the alternative method to determine survival fraction of the irradiated HT-29 colon cancer cells

A multiple colorimetric assay has been introduced to evaluate the proliferation and determination of survival fraction (SF) of irradiated cells. The estimation of SF based on the cell‑growth curve information is the major advantage of this assay. In this study, the utility of multiple‑MTS assay for the SF estimation of irradiated HT‑29 colon cancer cells, which were plated before irradiation, was evaluated. The SF of HT‑29 colon cancer cells under irradiation with 9 MV photon was estimated using multiple‑MTS assay and colony assay. Finally, the correlation between two assays was evaluated. Results showed that there are no significant differences between the SF obtained by two assays at different radiation doses (P > 0.05), and the survival curves have quite similar trends. In conclusion, multiple MTS‑assay can be a reliable method to determine the SF of irradiated colon cancer cells that plated before irradiation.