肿瘤成纤维细胞通过外泌体miR-21促进膀胱癌细胞侵袭转移

Exosomal miR-21 secreted by CAF promotes invasion and metastasis of bladder cancer cells

目的:探讨外泌体miR-21参与肿瘤相关成纤维细胞(cancer-associated fibroblast,CAF)促进膀胱癌细胞侵袭转移的作用及机制。方法:利用组织块贴壁法分别从膀胱癌和癌旁组织分离CAF和正常成纤维细胞(normal fibroblast,NF),利用荧光实时定量PCR检测膀胱癌组织,CAF、NF和相应外泌体,以及外泌体共孵育的膀胱癌T24细胞中miR-21的相对表达。通过Transwell侵袭迁移实验检测CAF、CAF分泌的外泌体及miR-21对膀胱癌细胞侵袭迁移能力的影响。蛋白质印迹及荧光素酶实验明确miR-21的靶基因。结果:相较于癌旁组织,miR-21在膀胱癌组织,尤其是分期较晚的浸润性膀胱癌组织中高表达。CAF分泌的外泌体中miR-21的表达水平明显高于NF分泌的外泌体。与CAF、CAF分泌的外泌体孵育及转染miR-21,可显著增强T24细胞侵袭迁移的能力。进一步荧光素酶实验证实miR-21可靶向抑制同源性磷酸酶张力蛋白(PTEN)的表达。结论:CAF可释放高表达miR-21的外泌体,经膀胱癌细胞摄取后,通过靶向抑制PTEN,促进膀胱癌细胞侵袭转移的发生。

Objective:To explore the role and potential mechanism of exosomal involved in process of cancer-associated fibroblast(CAF)promoting the invasion and metastasis of bladder cancer cells.Methods:CAF and normal fibroblast(NF)was isolated from bladder cancer and normal tissues adjacent to the cancer,respectively.The expression of was assessed in tissues and cell lines of bladder cancer,CAF,NF and exosomes.The transwell invasion and metastasis assays were applied to test the effect of CAF,CAF induced exosomes and on the invasion and metastasis ability of bladder cancer cells.The confirmation of target gene of was performed with luciferase assay.Results:Compared with controls,was highly expressed in bladder cancer tissues,especially those with late stages.Exosomes released from CAF showed higher expression of than that from NF.Incubation with CAF,CAF secreted exosomes,or transfection of mimics could significantly enhance the ability of T24 cells to invade and migrate.Exosomal absorbed by bladder cancer cells could promote the invasion and metastasis by targeting PTEN.Conclusion:Exosomal could regulate the process of CAF promoting the invasion and metastasis of bladder cancer cells.