Anti-proliferative Effect On Tumor Cells Of Kaempferol-7-O-β-D-glucoside Isolated From Smilax China L. Rhizome

Anticancer drug research is a significant field in life science. Natural products, with various structures, are important resource of anticancer lead compounds. Smilax china L., popularly known in China as'Baqia', has various pharmacological effects including anti-inflammatory, anticancer, anticoagulation and antioxidant activity.Kaempferol-7-O-β-D-glucoside (KG), a flavonoid glycoside, isolated from Smilax china L. rhizome, displayed marked anticancer activity on a panel of established cancer cells, of which, HeLa human cervix carcinoma cells were the most sensitive. Meanwhile, the cytotoxic effects of KG on normal human cells were much smaller than on cancer cells. This work studied the molecular mechanisms underlying KG induced growth inhibition in HeLa cells. The results showed that KG induced G2/M phase growth arrest correlated with Cyclin B1 and Cdk1 decrease in a p53-independent manner, and also caused an increase in apoptosis, which was confirmed by characteristic morphological changes, evident DNA fragmentation, increased apoptotic sub-G1 population. Furthermore, inhibition of NF-κB nuclear translocation, up-regulation of Bax and down-regulation of Bcl-2, were observed in HeLa cells treated with KG, which indicated that the mitochondrial pathway was involved in the apoptosis signal pathway.In the model of Lewis lung carcinoma, the average tumor weights in 40mg/kg KG injection groups decreased by 34.2%±6.98% compared with those of the control. KG inhibited tumor growth in tumor-bearing mice, increased their viability significantly.In summary, KG displayed a significant anti-tumor effect through cell cycle arrest and apoptotic induction in vitro and vivo which suggested that KG might have therapeutic potential against cervix carcinoma.