Effect and Mechanism of Survivin on Hypoxia-Induced Multidrug Resistance of Human Laryngeal Carcinoma Cells

This study aimed at clarifying the mechanism and role of survivin in hypoxia-induced multidrug resistance (MDR) of laryngeal carcinoma cells. Human laryngeal cancer cells were incubated under hypoxia or normoxia. The expression of survivin was silenced by performing RNA interference. Additionally, by Western blot and real-time quantitative RT-PCR, survivin expression was detected. The sensitivity of human laryngeal carcinoma cells to multiple drugs was measured by CCK-8 assay. Meanwhile, the apoptosis of cells induced by cisplatin or paclitaxel was assessed by Annexin-V/propidium iodide staining analysis. Under hypoxic conditions, the upregulation of survivin was abolished by RNA interference. Then, CCK-8 analysis demonstrated that the sensitivity to multiple agents of laryngeal carcinoma cells could be increased by inhibiting survivin expression (P < 0.05). Moreover, Annexin-V/propidium iodide staining analysis revealed that decreased expression of survivin could evidently increase the apoptosis rate of laryngeal carcinoma cells that were induced by cisplatin or paclitaxel evidently (P < 0.05). Our data suggests that hypoxia-elicited survivin may exert a pivotal role in regulating hypoxia-induced MDR of laryngeal cancer cells by preventing the apoptosis of cells induced by chemotherapeutic drug. Thus, blocking survivin expression in human laryngeal carcinoma cells may provide an avenue for gene therapy.