Role of DDX53 in taxol-resistance of cervix cancer cells in vitro.

Cancer/Testis antigen DDX53 shows high expression level in various tumors and is involved in anti-cancer drug resistance. However, the functional study of DDX53 in cervix cancer remains unknown. In this study, the role of DDX53 in taxol-resistance of cervix cancer cells was investigated. In taxol-resistant HelaTR cells, DDX53 was significantly increased as compared to the parental HeLa cells. HelaTR cells also showed upregulation of multidrug resistant gene MDR1, invasive characteristics and decreased apoptosis. In addition, increased autophagy level was observed in HelaTR cells. Overexpression of DDX53 in HeLa and SiHa markedly led to greater resistance to taxol and cisplatin, whereas knockdown of DDX53 in HelaTR cells restored sensitivity, demonstrating that DDX53 regulated taxol resistance in cervix cancer cells. DDX53 overexpression in HeLa and SiHa cells enhanced invasion, migration and anchorage independent growth, DDX53 knockdown showed inverse effects in HeLaTR cells. When DDX53 expression was suppressed by siRNA, autophagic flux and drug resistance of HelaTR cells were decreased. In addition, DDX53 was upregulated in cervix cancer tissues from patient with a glassy cell carcinoma of cervix. Taken together, these results suggest that DDX53 plays a critical role in taxol-resistance by activating autophagy and a potential therapeutic target for the treatment of taxol-resistant cervix cancer.