Reversing effect of sorcin in the drug resistance of human nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is one of the most common cancers originating in the nasopharynx, and chemoresistance is an essential aspect of NPC chemotherapy failure. Sorcin has been implicated in multidrug resistance (MDR) of many types of human tumor. However, the effect and mechanism of Sorcin in MDR of human NPC is not fully clear. In this report, we silenced Sorcin in human NPC CNE2/DDP cells, and explored the role of Sorcin in MDR reversal. The results showed an increased cytotoxicity of cisplatin and intracellular accumulation of Rhodamine-123 and glutathione depletion in Sorcin silencing CNE2/DDP cells. We also found a decreased messenger RNA and protein expression of multidrug resistance gene (MDR1), multidrug resistance-associated protein (MRP1), excision repair cross-complementing gene 1 (ERCC1), glutathione S-transferase-π (GST-n), RhoE, Bcl-2, and Survivin in Sorcin silencing CNE2/DDP cells. The increased expression of PTEN and decreased expression of p-Akt and NF-κB suggested that the key cellular signaling pathways were triggered by Sorcin silencing. We concluded that Sorcin silencing would contribute to establish a potent target point for MDR reversal.