PHPS1通过调控口腔鳞状细胞癌内ROS/SHP-2/AMPK活性促进PD-L1丝氨酸磷酸化进而加速肿瘤凋亡  

PHPS1 enhances PD-L1 serine phosphorylation by regulating ROS/SHP-2/AMPK activity to promote apoptosis of oral squamous cell carcinoma cells

作　　者：张晋弘[1] 刘昕[2] 刘健[2] ZHANG Jinhong;LIU Xin;LIU Jian(Department of Stomatology,First Hospital of Hebei Medical University,Shijiazhuang 050031,China;Department of Stomatology,Fourth Hospital of Hebei Medical University,Shijiazhuang 050011,China)

机构地区：[1]河北医科大学第一医院口腔科,河北石家庄050031 [2]河北医科大学第四医院口腔科,河北石家庄050011

出　　处：《南方医科大学学报》2024年第12期2469-2476,共8页Journal of Southern Medical University

基　　金：2023年度医学科学研究重点课题计划项目(20230157);2019年河北省政府资助临床医学优秀人才培养项目。

摘　　要：目的探讨PHPS1通过对口腔鳞状细胞癌细胞ROS/酪氨酸磷酸酶SHP-2/AMPK活性进而促进PD-L1丝氨酸磷酸化进而加速肿瘤凋亡的机制研究,分析腺苷酸活化蛋白激酶(AMPK)对于低氧环境下肿瘤内血管生成的影响。方法6~8周龄健康裸鼠16只,皮下移植瘤模型分为Control组和PHPS1组,8只/组,培育14 d后观察肿瘤的生长情况,并将其切片进行HE染色固定并拍照。将人口腔鳞状细胞癌Ca9-22细胞系培养后分为Control组、PHPS1组、Control+Compound C组(Compound C为AMPK抑制剂)、PHPS1+Compound C组在1%低氧环境下培养,通过Western blotting对细胞内SHP-2、AMPK、HIF-1α、PD-L1、caspase-8、caspase-3和BAX含量进行检测。结果裸鼠成瘤与血管新生实验结果显示PHPS1抑制了裸鼠体内肿瘤生长和血管新生(P<0.05)。Western blotting分析显示PHPS1降低了SHP-2、HIF-1α、PD-L1、ERK2、STAT3和VEGF的表达,同时增加了AMPK的表达(P<0.05)。加入AMPK抑制剂后,PHPS1对HIF-1α和PD-L1的抑制作用减弱(P<0.05)。此外,PHPS1促进了caspase-3、caspase-8、PD-L1 S195磷酸化和Bax蛋白的表达,这些效应在加入AMPK抑制剂后也有所减弱(P<0.05)。HE染色结果表明PHPS1组肿瘤血管生成数量减少(P<0.01)。结论在缺氧环境下可以通过调节SHP-2/AMPK活性进而促进PD-L1丝氨酸磷酸化进而加速肿瘤凋亡。Objective To investigate the mechanism of PHPS1 for promoting apoptosis of oral squamous cell carcinoma cells and the role of AMPK in regulating tumor angiogenesis under hypoxic conditions.Methods Human oral squamous cell carcinoma Ca9-22 cells cultured in hypoxic conditions(1%O2)were inoculated subcutaneously in 16 nude mice,which were divided into control group and PHPS1 group(n=8)for treatment with 10%DMSO and 10%PHPS1 respectively.Tumor growth in the mice was monitored till 14 days after the treatment,and the xenografts were examined pathologically using HE staining.In Ca9-22 cells cultured in 1%O2,the effect of PHPS1,compound C(an AMPK inhibitor),and their combination on expressions of SHP-2,AMPK,HIF-1α,PD-L1,caspase-8,caspase-3 and BAX were evaluated using Western blotting.Results In the tumorbearing nude mice,PHPS1 treatment significantly inhibited tumor growth and neovascularization.HE staining showed significantly reduced tumor angiogenesis in PHPS1-treated mice.In Ca9-22 cells in hypoxic cultures,PHPS1 treatment significantly decreased the expression levels of SHP-2,HIF-1α,PD-L1,ERK2,STAT3 and VEGF and increased the expression of AMPK.The inhibitory effects of PHPS1 on HIF-1αand PD-L1 were obviously attenuated by the addition of compound C.PHPS1 also enhanced the expressions of caspase-3,caspase-8 and Bax proteins and increased the phosphorylation levels of PDL1 and S195 in Ca9-22 cells,and these effects were effectively attenuated by compound C.Conclusion PHPS1 can enhance PDL1 serine phosphorylation by regulating SHP-2/AMPK activity to promote apoptosis of oral squamous cell carcinoma cells under hypoxic conditions.

关 键 词：SHP-2 AMPK 口腔鳞状细胞癌 PD-L1 

分 类 号：R739.8[医药卫生—肿瘤]