SiRNA Knock-Down Of HIF-1α Resulted In Dramatically Changes In Cell Cycle And Viability Of U87 Cell Line

HIF-1 is a transcription factor, composed of HIF-1α and HIF-1β subunits and functions as a masterregulator of oxygen homeostasis in all metazoan species. Upon hormonal stimulation or in oxygendeficientmicro-environment, HIF-1α is activated by ROS through a complex signaling network.Some studies showed that overexpression of HIF-1α is a negative prognostic indicator in manyhuman cancers such as breast, cervix, oropharynx, ovary and uterus. Moreover, significantassociationsbetween HIF-1α overexpression and patient mortalityhave been shown in cancers of thebrain. Here we aimed that to evaluate the effect of selective gene silencing ofHIF-1α with specificshort interfering RNA (siRNA) on the cell cycle and viability of U87 cell line as a human primaryglioblastoma cell line. U87 cells culturedin DMEM with 10% FBS supplementedwith penicillin andstreptomycin. Transfer of a specific siRNA against HIF-1α was performed by Lipofectamine®2000.RT-PCR analysis was performed after 24, 48 and 72 hours posttransfection.Using flowcytometry test and MTT assay, cell cycle and viability of transfected cells were analyzed. Using RTPCRmethod, we showed a significant down-regulation of HIF-1α in 48 hours transfectedcells incomparison with un-transfected cells. Moreover, we found knock down of HIF-1α significantly affectthe cell cycle and survival of u87 cells. Our results highlight the importance of Hif-1a as a candidatetarget in the field of cancer therapy.