Baicalein Exerts Anticancer Effect in Nasopharyngeal Carcinoma In Vitro and In Vivo.

Baicalein, an active ingredient separated from Astragalus membranaceus, has shown its anticancer ability in various cancers. However, its effect on nasopharyngeal carcinoma has not been explored yet. The present study aimed to investigate the effect of baicalein on the growth, proliferation, apoptosis, and cell cycle of human nasopharyngeal carcinoma cells, as well as transplanted nude mouse xenograft. The results showed that baicalein inhibited the growth and proliferation of CNE1 and CNE2 cells in a time- and concentration-dependent manner. It also caused a significant increase in the number of cells in the G₀/G₁ phase and a decrease in the G₂/M phase, thereby reducing the number of cells entering mitosis and inhibiting the proliferation of tumor cells. Baicalein also significantly induced apoptosis of CNE1 and CNE2 cells. Western blots showed that baicalein decreased the expression of Bcl-xl and Mcl-1 and increased the expression of Bax, Bad, and caspase 3, 8, and 9. In CNE1- and CNE2-transplanted tumors of mice, baicalein significantly inhibited tumor growth. In conclusion, baicalein could inhibit the growth and proliferation of human nasopharyngeal carcinoma cells, change their cell cycle, and induce apoptosis. Baicalein also effectively limits both CNE1- and CNE2-transplanted tumors in nude mice. Downregulation of Bcl-xl and Mcl-1 proteins and upregulation of Bax and Bad may be involved in the mechanism.