To evaluate the effect of preoperative transcatheter arterial chemoembolization( TACE) on apoptosis of hepatocellular carcinoma (HCC) cells Methods A total of 136 patients with HCC underwent liver resection One to five courses of TACE prior to liver resection were performed in 79 patients (TACE group), in which one to four courses of chemotherapy alone were performed in 11 patients ( group A), one to five courses of chemotherapy combined with iodized oil were per formed in 33 patients (group B), one to three courses of chemotherapy combined w ith iodized oil and gelatin sponge were performed in 23 patients group C) and on e to three courses of chemotherapy combined with iodized oil, ethanol and gelati n sponge were performed in 12 patients (group D) The other 57 patients only re ceived liver resection (non TACE group) The extent of apoptosis was analyzed by transferase mediated dUTP nick end labeling (TUNEL) staining The expressi ons of Bcl 2 and Bax protein were detected by immunohistochemical method Results The apoptotic index(AI) and level of Bax protein in HCC cells were significantly higher in groups A,B,C and D than those in the non TACE group ( P <0 05) The level of Bcl 2 protein and ratio of Bcl 2 to Bax protein of HCC cells were significantly lower in Groups A, B, C and D than those in the non TACE group ( P <0 05) Conclusion Preoperative TACE regimens may enhance apoptosis of HCC cells by up regulating the expression of Bax protein and down regulating the expression of Bcl 2 prot ein and ratio of Bcl 2 to Bax protein expression To evaluate the effect of preoperative transcatheter arterial chemoembolization (TACE) on apoptosis of hepatocellular carcinoma (HCC) cells Methods A total of 136 patients with HCC underwent liver resection One to five courses of TACE prior to liver resection were performed in 79 patients (TACE group ), in which one to four courses of chemotherapy alone were performed in 11 patients (group A), one to five courses of chemotherapy combined with iodized oil were per formed in 33 patients (group B), one to three courses of chemotherapy combined w ith iodized oil and gelatin sponge were performed in 23 patients group C) and on e to three courses of chemotherapy combined with iodized oil, ethanol and gelati n sponge were performed in 12 patients (group D) The other 57 patients only re ceived liver resection (non TACE group) The extent of apoptosis was analyzed by transferase mediated dUTP nick end labeling (TUNEL) staining The expressi ons of Bcl 2 and Bax protein were dete cted by immunohistochemical method Results The apoptotic index (AI) and level of Bax protein in significantly higher in groups A, B, C and D than those in the non TACE group (P <0 05) The level of Bcl 2 protein and ratio of Bcl 2 to Bax protein of HCC cells were significantly lower in Groups A, B, C and D than those in the non TACE group (P <0 05) Conclusion Preoperative TACE regimens may enhance apoptosis of HCC cells by up regulating the expression of Bax protein and down regulating the expression of Bcl 2 prot ein and ratio of Bcl 2 to Bax protein expression