ABSTRACT
Aim To investigate the sensitization effect of total flavonoids of litchi seed (TFLS) to paclitaxel (PTX) on prostate cancer paclitaxel resistance (PCa-Txr) cells and the synergistic inhibitory effect of TFLS combined with PTX. Methods CCK-8 method was carried out to detect the inhibitory effect of TFLS and PTX on PCa-Txr cells as well as corresponding parental cells. PCa-Txr cells were either pre-treated or simultaneously treated with low cytotoxic dose of TFLS to observe the sensitivity of PCa-Txr cells to PTX. The synergistic inhibitory effect of TFLS combined with PTX on the proliferation of PCa-Txr cells were observed according to the method recommended by Chou T C. Combination index (CI) was used to determine whether TFLS and PTX had synergistic inhibitory effect. Results TFLS significantly inhibited the proliferation of PCa-Txr cells and parental cells in a certain time- and dose-dependent manner. The low dose of TFLS pre-treated or treated with PTX simultaneously failed to increase the sensitivity of PTX on PCa-Txr cells. TFLS combined with PTX significantly inhibited the proliferation of PCa-Txr cells with CI value less than one. Conclusions TFLS inhibits the proliferation of PCa-Txr cells, while TFLS combined with PTX has synergistic inhibitory effect on PCa-Txr cells. However, TFLS fails to increase the sensitivity of PCa-Txr cells to PTX.