Upregulation of bax Gene
Expression Promotes Paclitaxel-induced Apoptosis in Esophageal Carcinoma Cells
PENG Wei-Dan*, ZHANG Jie, HUI Hong-Xiang, XU
Yan-Ming, ZHU Feng, YANG An-Gang, WANG Cheng-Ji
( Department of Biochemistry, Fourth Military Medical University, Xi’an 710033,
China )
Abstract An
inducible mammalian expression vector of bax gene was constructed and
the control ability of metallothionein II promoter in esophageal carcinoma cell
line was systematically identified with luciferase report gene. After the
transfection of it into human esophageal carcinoma cell line Eca109, Bax
protein expression was analyzed by immunolcytochemical method.
Paclitaxel-induced apoptosis was determined by TUNEL assay, DNA ladder assay
and flow cytometry. Results showed that 140 μmol/L ZnSO4 for 12 h is
optimal for induction of bax gene expression. Under these conditions,
a clonal transfectant X1097#, expressing bax gene effectively, was
obtained. It was found that, X1097# had higher apoptotic rate and was more
sensible than Eca109. These results implied that Bax protein may play an
important role in paclitaxel-induced apoptosis. Therefore, bax protein may be
promising as an helping drug to improve therapeutic effects of paclitaxel.
Key words bax； apoptosis； paclitaxel； inducible
*Corresponding author： Tel, 86-29-3374516； e-mail, [email protected]