Combined antitumor effect of ursolic acid and 5-fluorouracil on human esophageal carcinoma cell Eca-109 in vitro

To study the combined antitumor effect and possible mechanisms of ursolic acid with 5-fluorouracil (5-FU) on human esophageal carcinoma cell Eca-109 in vitro. Eca-109 cells were treated with ursolic acid (10-50 mu mol/L) and/or 5-fluorouracil (48.0-768.8 mu mol/L) for 48 h in vitro. And then cell proliferation was determined by MTT assay. Cell cycle and apoptosis rate were analyzed by flow cytometry (FCM). The morphological changes of apoptosis were observed by fluorescent microscopy. At last the expression of P27(kip1), bcl-2 and bax were detected by western blot. In comparison with single agent treatment, the combination of ursolic acid and 5-fluorouracil produced greater efficacy in growth inhibition, cell cycle arrest at G0/G1 phase, and apoptosis induction (P < 0.05). Western blot analysis showed that the combination use of ursolic acid and 5-fluorouracil suppressed the expression of bcl-2 and increased the expressions of bax and P27(kip1). Ursolic acid combined with 5-fluorouracil showed adjuvant antiproliferative effects on human esophageal carcinoma cell Eca-109 in vitro, which mainly due to the induction of cell cycle arrest as well as apoptosis.