IL-17-JAK2/STAT3信号通路通过调控p53降低肝癌细胞化疗凋亡敏感性的研究

IL-17-JAK2/STAT3 signaling pathway reduces chemo-induced apoptosis in hepatocellular carcinoma through regulating p53

目的:通过研究肝癌细胞激活白介素-17-蛋白酪氨酸激酶2/信号转导及转录激活因子3(IL-17-janus protein tyrosine kinase 2/signal transducers and activators 3 of transcription,IL-17-JAK2/STAT3)信号通路调控p53表达并下调化疗的凋亡敏感性,以此探讨肝癌细胞化疗耐药的机制。方法:选取我院2012年5月至2015年1月收治的肝癌患者(病理学确诊)及健康体检者各30例,ELISA检测肝癌患者化疗前后及正常对照组血清中白介素-17(interlrukin-17,IL-17)浓度;培养肝癌HepG2细胞,分别加入anti-IL-17R及IL-17后与奥沙利铂共培养,24 h后提取细胞蛋白,Western blot检测肝癌细胞凋亡相关蛋白BAX,Bcl-2表达情况及JAK2/STAT3信号通路活化情况及p53的表达情况;AG490特异性阻断JAK2/STAT3信号通路后检测p53的表达情况。结果:经奥沙利铂化疗后肝癌患者血清中IL-17的浓度[(143.96±33.20)pg/m L]明显高于化疗前[(77.36±15.66)pg/m L]及正常对照组[(26.61±4.95)pg/m L](P<0.05);肝癌细胞加入anti-IL-17R与奥沙利铂共培养24 h后,BAX表达量明显升高、Bcl-2表达量降低,磷酸化蛋白酪氨酸激酶(p-JAK2)、磷酸化信号转导及转录激活因子(p-STAT3)表达量均明显降低,p53表达量升高;而加入IL-17的肝癌细胞,BAX表达量明显降低、Bcl-2表达量明显升高,p-JAK2、p-STAT3表达量均明显升高,p53表达量明显降低。AG490阻断JAK/STAT通路后,肝癌细胞p53的表达水平明显升高。结论:肝癌细胞化疗过程中通过IL-17激活JAK2/STAT3信号通路调控p53的表达进而下调肝癌细胞凋亡敏感性,由此导致肝癌的化疗抵抗。

Objective：To investigate the regulation of p53 expression by IL-17-janus protein tyrosine kinase 2/signal transducers and activators 3 of transcription（IL-17-JAK2/STAT3） signaling pathway and down-regulation of the apoptotic sensitivity to chemotherapy and to explore the mechanism of drug resistance in hepatocellular carcinoma（HCC）. Methods：Thirty cases of HCC （pathological diag- nosis） and 30 cases of healthy physical examination in our hospital from May 2012 to January 2015 were chosen as research subjects. IL-17 level in serum was detected by ELISA. HepG2 cells were cultured and added to anti-IL-17R,IL-17 and oxaliplatin co-culture for 24 hours,then the protein was exacted to detect the apoptosis related protein BAX and Bcl-2 and key nodes protein of JAK2/ STAT3 signal pathway and the expression of p53 by Western blot. The expression of p53 was detected whileJAK2/STAT3 pathway was blocked with AG490. Results ：After chemotherapy, HCC patients serum IL-17 level [（ 143.96± 33.20） pg/mL] was much higher than that before chemotherapy[（77.36 ± 15.66） pg/mL] and that of healthy check-up group[（26.61 ± 4.95） pg/mL]（P〈0.05）. After HepG2 cells being cultured with anti-IL-17R and oxaliplatin for 24 hours, the expression of BAX was increased while Bcl-2 was decreased, the expressions of p-jak2, p-STAT3 were significantly decreased while p53 was increased. After adding IL-17 to HepG2 cells, BAX was decreased while Bcl-2 was increased significantly, p-jak2, p-STAT3 were significantly increased while p53 was significantly re- duced. After adding AG490 blocking agents, p53 expression was increased. Conclusion：IL-17 could regulate p53 expression throughactivated JAK2/STAT3 signaling pathway, which can reduce the chemotherapy sensitivity of HCC.