ABSTRACT
Objective:To investigate the inducing effects of sunitinib malate on expression of NKG2D ligands in nasopharyngeal carcinoma cell ABCG2high CNE2/DDP.Methods:ABCG2highCNE2/DDP cells and Allo-NK cells were isolated by magnetic activated cell sorting(MACS).Flow cytometry was used to evaluate the purity of isolated cells and the expression of NKG2D-ligands on target cells before and after incubation with sunitinib malate.Then the cytotoxic sensitivity of treated and un-treated ABCG2high CNE2/DDP cells to Allo-NK cells were measured by LDH releasing assay.Results:The positive rate of ABCG2 in ABCG2highCNE2/DDP cells was(91.40?2.32)%.More than 90% of isolated Allo-NK cells were proven to be CD3-CD16+CD56+ cells.The expression of MICA,MICB,ULBP1,ULBP2 and ULBP3 on ABCG2high CNE2/DDP cells incubated with sunitinib malate increased from(2.92?0.33)%,(4.27?0.33)%,(5.80?0.62)%,(11.10?3.15)%,and(7.75?1.14)% to(89.12?4.56)%,(66.10?2.22)%,(67.56?4.19)%,(69.37?8.83)%,and(63.28?3.31)%,respectively.At the E ∶T ratios of 10 ∶1 and 20 ∶1,the cytotoxic sensitivities of ABCG2high CNE2/DDP cells to Allo-NK cells increased from(15.32?13.86)% and(27.26?6.81)% to(41.12?4.12)% and(57.25?2.37)%,respectively,after treatment with sunitinib malate,with significantly difference found in the cytotoxic sensitivities of target cells in each group before and after sunitinib malate treatment(F=15.58,P=0.000).Conclusion:Sunitinib malate can up-regulate expression of NKG2D-ligands(MICA/B,ULBP1-3)in ABCG2high nasopharyngeal carcinoma cells,which results in higher cytotoxic sensitivity to Allo-NK cells.
