Chk1 gene scilencing potentiates human hepatoma Huh7 cells to curcumin-induced apoptosis / 中国癌症杂志

ABSTRACT

Background and purpose:Checkpoint kinase 1 and 2 have been proposed to be potential therapeutic targets to sensitize cancers to radioor chemo-therapeutics. However, little is known about whether Chk1/2 is also a suitable target for sensitizing cancers to curcumin. In the present study, we investigated effects of Chk1/2 siRNA on curcumin-induced apopotosis in hepatoma cell line Huh7 and evaluated the effectiveness of Chk1/2 as a therapeutic target to potentiate human hepatoma to curcumin. Methods:Effect of curcumin on the cell cycle checkpoint-associated proteins was detected by Western blot. The knockdown efficacy of Chk1/2 siRNA was measured by RT-PCR and Western blot. Effect of Chk1/2 siRNA on curcumin-induced apoptosis in Huh7 cells was evaluated by DAPI staining. Effect of Chk1/2 siRNA on cell cycle distribution in curcumin-treated Huh7 cells was analyzed by flow cytometry. Results:Curcumin significantly inhibited phosphorylation of cell cycle checkpoint-associtaed proteins Chk1(S317), Cdc25C(S216) and Cdk1(Y15). Chk1 siRNA decreased Chk1 mRNA and protein by 95% and 92% and Chk2 siRNA decreased Chk2 mRNA and protein by 60% and 55% respectively as compared with negative control siRNA (P