激活Toll样受体2可以促进胃癌细胞中的OXPHOS和糖酵解

Activation of Toll-like Receptor 2 Via Specific Agonists Promotes OXPHOS and Glycolysis in Gastric Cancer Cells Rather than other Toll-like Receptors

目的:调查TLR家族中哪种TLR受体的配体依赖性激活可引起胃癌细胞的代谢重编程。方法:通过实时荧光定量PCR(RT-qPCR)和蛋白质印迹(WB)在一组人GC细胞中测量TLR家族成员的表达。通过进行Seahorse生物能测定以及测量L-乳酸和活性氧(ROS)的产生,确定激动剂对不同TLR(TLR2、4、9)诱导的人GC细胞的代谢变化;通过RT-qPCR在被刺激的GC细胞中分析了涉及氧化磷酸化和糖酵解的基因的表达;通过Western印迹表征SOD2的表达。结果:由合成分子或全病原体抗原激活的TLR2信号传导增强了胃癌细胞中高表达TLR2的细胞株的糖酵解活性和线粒体呼吸,而配体诱导的TLR4和TLR9活化抑制了线粒体呼吸或细胞外酸化率。同时,涉及葡萄糖代谢和氧化还原系统调节的基因,例如HIF1A,PFKFB3和SOD2,在TLRs下游被上调。结论:由配体诱导的特定TLRs的激活介导了人类GC细胞中不同的代谢表型。TLR2是唯一同时促进OXPHOS和糖酵解的家族成员,这可能导致肿瘤进展。

Objective: To investigate whose ligand dependent activation in the family of Toll-like receptor(TLR) is able to reprogram metabolism of gastric cancer. Methods: The m RNA and protein expression level of TLR family members in human GC cells were measured by RT-qPCR and Western blot respectively. Metabolic changes in human GC cells that were induced by agonists for various TLRs(TLR2, 4, 9) were quantified by Seahorse bioenergetic assay and production of L-lactate and ROS. The expressions of genes involved in the oxidative phosphorylation and glycolysis were also profiled in the stimulated GC cells by RT-qPCR. The protein expression level of SOD2 was quantified by Western blot. Results: The TLR2 signaling activated by either synthetic molecules or whole pathogen antigen significantly enhanced glycolytic activity and mitochondrial respiration in the cells with high level of TLR2, whereas ligand-induced activation of TLR4 and TLR9 inhibited mitochondrial respiration or extracellular acidification rate. Furthermore, the expression of genes involved in the glucose metabolism and redox system regulation, such as HIF1 A, PFKFB3 and SOD2, were upregulated. Conclusion: Our study revealed that activation of various TLRs would lead to different metabolic phenotypes in the human GC cells. Among them, TLR2 promotes both OXPHOS and glycolysis, which may contribute to the progression of gastric cancer.