ABSTRACT
Objective: To investigate the effect of curcumin (Cur) on cycle in HepG2 cells and the action of microtubule system for it. Methods: The proliferation inhibition of Cur on HepG2 cells was evaluated by MTT assay; The effect of Cur on the cycle of HepG2 cells was analyzed by flow cytometry; Confocal laser scanning microscopy (CLSM) was used to observe the changes of microtubule in HepG2 cells after treated with Cur; Western blotting was performed to determine the expression of α-tubulin; The in vitro effects of Cur on tubulin polymerization and depolymerization activities were studied. Results: Cur inhibited the proliferation of HepG2 cells in a dose- and time-dependent manner. With Cur concentration increasing, the proportion of HepG2 cells arrested in G2/M phase was also increased. CLSM showed that Cur could seriously destroy the cell microtubule structure and change the polymerization state of tubulin. Western blotting showed that the decrease of the expression level of α-tubulin was related to Cur concentration. Cur could also interfere the microtubule polymerization and depolymerization activities. Conclusion: Cur could inhibit the proliferation of HepG2 cells by destroying the microtubule structure and downregulating the expression of α-tubulin, and make HepG2 cells arrested in G2/M phase.