Impact of High ABCA3 Expression in Nasopharyngeal Carcinoma Stem Cells on theResistance to Cisplatin / 医药导报

ABSTRACT

Objective To investigate the role of ATP￣binding cassette ( ABC ) family on the resistance of nasopharyngeal carcinoma (NPC) stem cells (CSCs) to cisplatin. Methods We compared the differences between the drug extravasation capability of CNE￣2 and CNE￣2S by using Rhodamine￣123 efflux assay. We determined the mRNA and protein expression levels of ABC transport family members, including ABCA3,ABCB1,ABCB5,ABCC1,ABCC2 and ABCG2,after 48 h being treated with 1 μmol.L-1 cisplatin by RT￣PC and Western blotting.Rhoamine￣123 efflux and apoptosis by cisplatin in two kinds of cells was examined by ABCA3 gene silencing with specific small￣interfering RNA. Results The IC50 of cisplatin on CNE￣2S was 4.1 fold to that on CNE￣2(P<0.05).For the relative drug effluent activity and Na+K+ ATPase activity,CNE￣2S was 4.8 fold to CNE￣2(P<0.05),suggested that CNE￣2S expressed more ABCA3,ABCB1,ABCC1 and ABCG2 in comparison to CNE￣2(P<0.05).After 48 h treatment with 1 μmol.L-1 cisplatin,ABCA3 specifically highly expressed in CNE￣2S (P<0.05), and knocking down of ABCA3 resulted in reduction of rhodamine￣123 efflux and increase of apoptosis. Conclusion The cisplatin resistance of NPC CSCs is associated with enhanced expression of ABCA3,ABCC1 and ABCG2, suppression of ABCA3 could reverse the resistance of NPC CSCs to cisplatin.