JAK2/STAT3信号通路调控细胞自噬水平对胃癌血管生成的影响机制研究

Mechanism of JAK2/STAT3 signal pathway regulating cellular autophagy levels on gastric cancer angiogenesis

目的:基于酪氨酸蛋白激酶2(JAK2)/信号转导和转录激活因子3(STAT3)信号通路调控细胞自噬水平,观察其对胃癌血管生成的影响机制。方法:利用Human Protein Atlas和GEPIA数据库在线分析胃癌组织及正常组织JAK2、STAT3的表达水平、患者预后生存情况。免疫组化检测正常胃组织、胃癌组织及癌旁组织标本p-JAK2、p-STAT3的表达水平,并分析p-JAK2、p-STAT3表达水平与患者临床病理参数的关系。利用脂质体转染法将靶向JAK2的miR-375转染至BGC-823细胞并分为3组,control组、si-mimic NC组、si-JAK2组。采用qRT-PCR检测JAK2、STAT3 mRNA表达水平;Western blot检测p-JAK2、p-STAT3、微管相关蛋白轻链3(LC3)、酵母自噬相关基因6的哺乳动物同源体(Beclin1)、血管内皮生长因子(VEGF)的表达水平;透射电镜观察细胞自噬泡的形成;血管形成实验检测细胞血管生成能力。结果:Human Protein Atlas和GEPIA在线数据库显示胃癌组织JAK2、STAT3的表达水平高于正常组织,且JAK2、STAT3表达越高,预后生存期越短(P<0.05)。免疫组化结果显示胃癌组织p-JAK2、p-STAT3的表达水平明显高于癌旁组织和正常胃组织(P<0.05)。p-JAK2、p-STAT3表达越高,肿瘤越大,浸润深度越严重,分化程度越低,淋巴结越容易发生转移。细胞实验显示,与control组和si-mimic NC组相比,si-JAK2组细胞p-JAK2、p-STAT3、VEGF水平明显降低,LC3、Beclin1表达水平、自噬能力明显升高,血管生成能力明显降低(P<0.05)。control组和si-mimic NC组上述差异无统计学意义(P>0.05)。结论:JAK2、STAT3在胃癌组织和细胞中表达量均升高,具有促癌作用,可能通过激活JAK2/STAT3信号通路抑制细胞自噬水平、增加血管生成能力,为调控自噬途径治疗胃癌提供新思路。

Objective:Based on the janus protein tyrosine protein kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling pathway to regulate cell autophagy level,to observe their mechanism of influence on angiogenesis of gastric cancer.Methods:Human Protein Atlas and GEPIA databases were used to analyze the expression levels of JAK2 and STAT3 in gastric cancer tissues and normal tissues,as well as the prognosis and survival of patients.Immunohistochemistry was used to detect the expression levels of p-JAK2 and p-STAT3 in normal gastric tissue,gastric cancer tissue and adjacent tissue specimens,and analyze the relationship between the expression levels of p-JAK2 and p-STAT3 and the clinical pathological parameters of patients.To miR-375 targeting JAK2 was transfected into BGC-823 cells using liposome transfection method and divided into 3 groups:control group,si-mimic NC group,and si-JAK2 group.qRT-PCR was used to detect JAK2 and STAT3 mRNA expression levels;Western blot was used to detect p-JAK2,p-STAT3,microtubule-associated protein light chain 3(LC3),and yeast autophagy-related gene 6 in lactation Animal homologs(Beclin1),vascular endothelial growth factor(VEGF)expression levels;transmission electron microscopy to observe the formation of autophagic vesicles;angiogenesis test to detect the angiogenesis ability of cells.Results:Human Protein Atlas and GEPIA online databases showed that the expression levels of JAK2 and STAT3 in gastric cancer tissues were higher than those in normal tissues,and the higher the expression of JAK2 and STAT3,the shorter the prognostic survival(P<0.05).The results of immunohistochemistry showed that the expression levels of p-JAK2 and p-STAT3 in gastric cancer tissues were significantly higher than those in adjacent tissues and normal gastric tissues(P<0.05).The higher the expression of p-JAK2 and p-STAT3,the larger the tumor,the more severe the depth of invasion,the lower the degree of differentiation,and the easier it is for lymph node metastasis to occur.Cell experiments showed that compared with the control group and the si-mimic NC group,the levels of p-JAK2,p-STAT3,and VEGF in the si-JAK2 group were significantly reduced,and the expression levels of LC3,Beclin1,autophagy and angiogenesis were significantly increased.The ability of angiogenesis was significantly reduced(P<0.05).The above difference between the control group and the si-mimic NC group was not statistically significant(P>0.05).Conclusion:JAK2 and STAT3 are elevated in gastric cancer tissues and cells,and have cancer-promoting effects,which may inhibit cell autophagy and increase angiogenesis by activating the JAK2/STAT3 signaling pathway,and provide new ideas for regulating autophagy pathways in the treatment of gastric cancer.