舒尼替尼诱导自然杀伤细胞2族成员D配体表达对自然杀伤细胞杀伤舌鳞癌CAL27细胞敏感性的影响

Effect of sunitinib-induced natural killer group 2 member D ligand expression on killing sensitivity of natural killer cells to tongue squamous cell carcinoma CAL27 cells

目的探讨舒尼替尼诱导自然杀伤细胞2族成员D(NKG2D)配体(NKG2DL)的表达对自然杀伤(NK)细胞杀伤舌鳞癌CAL27细胞敏感性的影响。方法将对数生长期的CAL27细胞分为未处理组和舒尼替尼组,舒尼替尼组采用舒尼替尼处理,未处理组细胞未经舒尼替尼处理。采用细胞克隆形成实验检测两组CAL27细胞的增殖能力;采用流式细胞术检测两组CAL27细胞的凋亡、NKG2DL(MICA、MICB、ULBP1、ULBP2和ULBP3)阳性细胞的表达及健康人NK细胞的纯度;采用免疫蛋白印迹法检测两组CAL27细胞中NKG2DL(MICA、MICB、ULBP1、ULBP2和ULBP3)蛋白的表达水平。再将舒尼替尼组分为舒尼替尼-NKG2D组和舒尼替尼-对照组,舒尼替尼-NKG2D组加入经NKG2D单抗处理后的NK细胞,舒尼替尼-对照组加入未经NKG2D单抗处理的NK细胞,同时未处理组加入未经NKG2D单抗处理的NK细胞(作为未处理-NK组)。采用乳酸脱氢酶释放法检测NK细胞对CAL27细胞的杀伤敏感性。结果(1)与未处理组相比,舒尼替尼组CAL27细胞的增殖能力降低、凋亡率增加,CAL27细胞中的MICA、MICB、ULBP1和ULBP2蛋白表达水平均升高(均P<0.05),而两组CAL27细胞ULBP3蛋白表达水平差异无统计学意义(P>0.05)。(2)与未处理-NK组相比,NK细胞对经舒尼替尼处理的CAL27细胞的杀伤敏感性增强(均P<0.05)。(3)采用NKG2D抗体封闭NK细胞表面的NKG2D受体后,NK细胞对经舒尼替尼处理的CAL27细胞的杀伤敏感性低于未采用NKG2D单抗处理的CAL27细胞的杀伤敏感性(均P<0.05)。结论舒尼替尼可以抑制舌鳞癌细胞CAL27细胞的增殖,促进其凋亡,上调CAL27细胞中NKG2DL(MICA、MICB、ULBP1、ULBP2)的表达水平,增强NK细胞对CAL27细胞的杀伤敏感性。

Objective To investigate the effect of sunitinib-induced natural killer group 2 member D ligand(NKG2DL)expression on the killing sensitivity of natural killer(NK)cells to tongue squamous cell carcinoma CAL27 cells.Methods CAL27 cells in logarithmic phase were divided into non-treatment group and sunitinib group.The sunitinib group received sunitinib for treatment,while the non-treatment group did not receive sunitinib for treatment.In both groups,cell colony formation assay was used to detect the proliferation ability of CAL27 cells;flow cytometry was employed to detect the apoptosis of CAL27 cells,the expression of NKG2DL(MICA,MICB,ULBP1,ULBP2 and ULBP3)-positive cells,and the purity of healthy people′s NK cells;Western blotting assay was used to detect the expression level of NKG2DL(MICA,MICB,ULBP1,ULBP2 and ULBP3)protein in CAL27 cells.Then the sunitinib group was further divided into sunitinib-NKG2D group and sunitinib-control group.The NK cells treated with NKG2D monoclonal antibody were added into the sunitinib-NKG2D group,while the NK cells not treated with NKG2D monoclonal antibody were added into the sunitinib-control group.At the same time,the NK cells not treated with NKG2D monoclonal antibody were added into the non-treatment group(non-treatment-NK group).Lactate dehydrogenase releasing assay was adopted to determine the killing sensitivity of NK cells to CAL27 cells.Results(1)Compared with the non-treatment group,the sunitinib group exhibited a decreased proliferation ability and an increased apoptosis rate of CAL27 cells,together with elevated expression levels of MICA,MICB,ULBP1,and ULBP2 proteins in CAL27 cells(all P<0.05),whereas there was no statistically significant difference in the expression level of ULBP3 protein in CAL27 cells between the two groups(P>0.05).(2)Compared with the non-treatment-NK group,NK cells had an increased killing sensitivity to sunitinib-treated CAL27 cells(all P<0.05).(3)NK cells harbored a lower killing sensitivity to sunitinib-treated CAL27 cells than to CAL27 cells without NKG2D monoclonal antibody treatment after NKG2D receptors on NK cells surface had been blocked by NKG2D antibody(all P<0.05).Conclusion Sunitinib can inhibit the proliferation of tongue squamous cell carcinoma CAL27 cells,promote their apoptosis,up-regulate the expression level of NKG2DL(MICA,MICB,ULBP1,ULBP2)in CAL27 cells,and enhance the killing sensitivity of NK cells to CAL27 cells.