Abstract:Objective：To observe the effect of antisense hypoxia inducible factor-1α(HIF-1α) on chemosensitivity of human pancreatic cancer cell line BxPC-3 under hypoxia. Methods：BxPC-3 cells were divided into 3 groups:(1)BxPC-3 cells were non-transfected with antisense HIF-1α plasmid and exposed to 0.5% O2 for 4hr (hypoxia control); (2)normoxic BxPC-3 cells were non-transfected with antisense HIF-1α plasmid (normoxia control); (3)BxPC-3 cells were transfected with antisense HIF-1α plasmid and exposed to 0.5% O2 for 4hr (experimental group). Expression of HIF-1α and survivin was detected by RT-PCR and Western Blot. Growth inhibition rates and apoptosis rates of BxPC-3 cells under different dosages of chemotherapeutic agents (5-fluorouracil, doxorubicin and gemcitabine) were measured by MTT colorimetric assay and flow cytometry (FCM). Results：Expression of HIF-1α was obviously down-regulated and at the same time survivin expression was markedly down-regulated in experimental group (P<0.05). Higher dosages (100 mg/L, 200 mg/L and 400 mg/L of 5-fluorouracil, 0.05 mg/L, 0.075 mg/L and 0.1 mg/L of doxorubicin, 10-9 mol/L, 10-8 mol/L and 10-7 mol/L of gemcitabine) caused a greater increase of inhibition in experimental group than in hypoxia control (P<0.05). Conclusions：The results demonstrate that antisense HIF-1α inhibits expression of survivin and enhances chemosensitivity of human pancreatic cancer cell BxPC-3. Blocking HIF-1α in pancreatic cancer cells may offer an avenue for gene therapy.