miR-506通过调控MCL-1抑制耐阿立替尼非小细胞肺癌A549细胞上皮间质转化的作用机制

目的:探究miR-506通过调控MCL-1对耐阿立替尼非小细胞肺癌A549细胞上皮间质转化（epithelial mesenchymal transformation，EMT）及侵袭转移的影响和作用机制。方法:收集2017年12月至2018年12月我院肿瘤科收治的经PET-CT结合组织病理活检及药敏试验确诊为耐阿立替尼的74例非小细胞肺癌患者的癌及癌旁组织以及人非小细胞肺癌A549细胞为研究对象，分别采用细胞转染、免疫组化染色（IHC）、qRT-PCR和Western Blot法检测上述临床组织和细胞样本中miR-506、MCL-1、BAX/Bcl-2凋亡信号途径及EMT标志蛋白表达水平；此外，采用Transwell细胞实验观察miR-506过表达和MCL-1敲减对A549细胞迁移和侵袭能力的影响。结果:免疫组化（IHC）结果显示肺癌患者癌组织中浸润性坏死性病理损伤较癌旁组织明显加重，且癌组织中MCL-1的阳性表达率为94.64%，明显高于癌旁组织的23.27%（P＜0.05）。qRT-PCR和Western Blot结果显示，肺癌组织中miR-506、BAX和E-cadherin的表达明显低于癌旁组织，而MCL-1、Bcl-2和N-cadherin的表达显著高于癌旁组织（P＜0.05）。细胞实验结果表明miR-506过表达和MCL-1敲减能够明显上调BAX和E-cadherin的表达，同时抑制Bcl-2和N-cadherin的表达（P＜0.05）；此外，miR-506过表达和MCL-1敲减均能显著抑制肺癌A549细胞的迁移和侵袭能力（P＜0.05）。结论:miR-506可能通过抑制BAX/Bcl-2/MCL-1凋亡途径发挥抑制耐阿立替尼非小细胞肺癌A549细胞EMT及诱导细胞凋亡作用，有望为临床抗肺癌转移及凋亡抑制靶向治疗提供新分子和靶点。

Mechanism of miR-506 inhibiting EMT of alitinib-resistant non-small cell lung cancer A549 cells by regulating MCL-1

Objective:To investigate the effect and mechanism of miR-506 on the EMT and invasion and metastasis of alitinib-resistant non-small cell lung cancer A549 cells by regulating MCL-1.Methods:The cancer and adjacent tissues and A549 cells of human non-small cell lung cancer (NSCLC) were collected from 74 patients with non-small cell lung cancer who were confirmed to be resistant to aritinib by PET-CT combined with histopathological biopsy and drug sensitivity test admitted to the department of oncology of our hospital from December 2017 to December 2018.Cell transfection,immunohistochemical staining (IHC),qRT-PCR and Western Blot were used to detect the apoptosis pathways of miR-506,MCL-1,BAX/Bcl-2 and the expression levels of EMT marker proteins in clinical tissues and cell samples.In addition,Transwell cell assay was used to observe the effects of miR-506 overexpression and MCL-1 knockdown on migration and invasion ability of A549 cells.Results:The results of immunohistochemistry(IHC) showed that the invasive necrotizing pathological injury of the lung cancer patients was significantly worse than that of the adjacent tissues,and the positive expression rate of MCL-1 in the cancer tissues was 94.64%,which was significantly higher than the 23.27% of the adjacent tissues (P＜0.05).The results of qRT-PCR and Western Blot showed that the expressions of miR-506,BAX and E-cadherin in lung cancer tissues were significantly lower than those in adjacent positive tissues,while the expressions of MCL-1,Bcl-2 and N-cadherin were significantly higher than those in adjacent tissues (P＜0.05).Cell experiments showed that miR-506 overexpression and MCL-1 knockdown significantly up-regulated the expression of BAX and E-cadherin,and inhibited the expression of Bcl-2 and N-cadherin (P＜0.05).In addition,both miR-506 overexpression and MCL-1 knockdown significantly inhibited the migration and invasion of lung cancer A549 cells (P＜0.05).Conclusion:miR-506 may plays a crucial role in inhibiting EMT of A549 cells of alitinib-resistant non-small cell lung cancer and inducing apoptosis by inhibiting BAX/Bcl-2/MCL-1 apoptosis pathway,which is expected to provide new molecules and targets for clinical targeted therapies against lung cancer metastasis and apoptosis inhibition.