RESUMO
PURPOSE: Hypoxia-inducible factor-1alpha (HIF-1alpha) primarily mediates the hypoxic response. HIF-1alpha induction by various stimuli contributes to cell proliferation and survival. To investigate the effect of HIF-1alpha, we used small interfering RNA (siRNA), and expected that cell apoptosis and sensitivity to chemotherapeutic drug increase, when we blocked the HIF-1alpha gene. Thus we performed in vitro and in vivo experiment to clarify the effect of hypoxia-inducible factor-1alpha on tumor growth. MATERIALS AND METHODS: We made control and HIF-1alpha siRNA using vector plasmid and then transfected Mia-paca cell lines with these RNAs. After selection with geneticin, two new cell lines were made, confirmed via immunoblotting. After treating with gemcitabine, each cell line was assayed to confirm the effect of HIF-1alpha siRNA using the cell proliferation assay and capase-3 assay. And then in vivo study was performed using female athymic nude mice. After subcutaneously injecting each new cell lines, intraperitoneal gemicitabine chemotherapy was performed for 3 weeks. During that period, we analyzed the difference of tumor growth rate. RESULTS: The tumor growth of HIF-1alpha siRNA-transfected group was slower than that of the control group both in vitro and in vivo experiment. CONCLUSION: The suppression of HIF-1alpha results in decrease of cell proliferation and increase of chemosensitivity of pancreatic cancer cell line. Therefore, targeting the HIF-1alpha may be useful treatment modality for some pancreatic cancers.