Objectives: The aim of the study was to observe the effect of antisense hypoxia-inducible factor 1alpha (HIF-1alpha) on progression, metastasis, and chemosensitivity of pancreatic cancer.
Methods: BxPc-3 cells transfected with antisense HIF-1alpha plasmid were exposed to 0.5% O2 for 4 hours. Expressions of HIF-1alpha, survivin, and beta1 integrin were detected by reverse transcriptase -polymerase chain reaction and Western blotting. Growth inhibition rates and apoptosis rates of BxPc-3 cells under different dosages of chemotherapy agents (5-fluorouracil, doxorubicin, and gemcitabine) were measured by MTT colorimetric assay and flow cytometry. The migration of BxPc-3 cells was assayed using transwell cell culture chambers. Subcutaneous transplantation of BxPc-3 cells in nude mice for 8 weeks was to assess progression and metastasis of pancreatic cancer.
Results: Expression of HIF-1alpha was obviously down-regulated, and at the same time, survivin and beta1-integrin expressions were markedly down-regulated in the experimental group (P < 0.05). Higher dosages (100, 200, and 400 mg/L of 5-fluorouracil; 0.05, 0.075, and 0.1 mg/L of doxorubicin; and 10(-9), 10(-8), and 10(-7) mol/L of gemcitabine) caused a greater increase of inhibition in the experimental group than in control (P < 0.05). The number of migrated BxPc-3 cells in the experimental group was far less than in control (P < 0.05). In vivo, the tumor size and weight in the experimental group were significantly lower than those in control (P < 0.05).
Conclusion: Our data demonstrate that antisense HIF-1alpha inhibits expressions of survivin and beta1 integrin, enhancing apoptosis in human pancreatic cancer cells and restraining the progression and metastasis of pancreatic cancer. Therefore, HIF-1alpha may play a very important role in progression, metastasis, and chemosensitivity of human pancreatic cancer. Blocking HIF-1alpha in pancreatic cancer cells may offer an avenue for gene therapy.