Figure 1.

TP4O causes cell death and inhibits cell proliferation in human CRC cell lines. (A) Cell viability was measured using the WST-8 assay. HCT116, RKO and CCD 841 CoN cells were treated with the indicated concentrations of TP4O for 24 h. Values were compared with 0 µM TP4O as the control, which was considered 100%. Cell viability was decreased in CRC cells in a dose-dependent manner. The IC₅₀ values of TP4O in HCT116 and RKO cells were 661 and 381 µM, respectively. The IC₅₀ value of TP4O in the human normal colon epithelial cell line CCD 841 CoN was 5,347 µM. (B) Cell proliferation was measured using a bromodeoxyuridine assay. HCT116, RKO and CCD 841 CoN cells were treated with the indicated concentrations of TP4O for 24 h. The values were compared with those obtained with 0 µM TP4O, which served as the control (100%). The percentage of cell proliferation decreased in a dose-dependent manner. The data are represented as the mean ± standard deviation. *P<0.05. **P<0.01. The results were obtained from three independent experiments. TP4O, terpinen-4-ol; CRC, colorectal cancer; IC₅₀, half maximal inhibitory concentration.