Apoptosis in tumor cells was induced by regulating the expression of two apoptosis\|associated proteins at the same time to investigate the possibility of curing tumor by gene therapy.The bax gene and hammerhead ribozyme specially targeted to bcl\|2 mRNA whose expression can be induced by ZnSO 4 were transfected into human esophageal carcinoma cell line Eca109 simultaneously and selected by G418.Transfectant was induced by 120 μmol/L ZnSO 4 for two days.The expression of the Bcl\|2 and Bax protein was identified by indirect immunofluorescent.Apoptosis was determined by TUNEL assay,apoptosis peak analysis and agarose gel electrophoresis.Results showed that the expression of Bcl\|2 was decreased whereas the expression of Bax was increased after being co\|transfected.30% or so apoptotic cells were induced.Moreover,the sensitivity to paclitaxel was enhanced 4 times and the effective time of paclitaxel was shortened nearly by half.These data demonstrate that regulating the expression of two apoptosis\|associated genes at the same time can induce apoptosis in tumor cells and accelerate apoptosis induced by chemotherapeutic drugs.It is more effective to cure tumor by correcting abnormal expression of multiple genes than by adjusting expression of single gene.