Zhang Wei, Mao Ye-Qing, Wang Hua, Yin Wen-Juan, Zhu Shao-Xing, Wang Wei-Cheng
Department of Urology, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, Zhejiang 310000 China.
Department of Urology, The First Affiliated Hospital of Zhejiang University, 79 Qinchun Road, Hangzhou, Zhejiang 310003 China.
Cancer Cell Int. 2015 May 6;15:49. doi: 10.1186/s12935-015-0189-x. eCollection 2015.
MicroRNA is a type of endogenous non-coding RNA implicated in various cellular processes, and has been intensely investigated in the field of cancer research for many years. Here, we investigated the functions and mechanisms of miR-124 in prostate cancer, which is a putative tumor suppressor reported in many carcinomas.
Using bioinformatics, talin 1 was indicated as a potential target of miR-124. We examined the expression levels of miR-124 and talin 1 in tissue specimens and cell lines. To explore the relationship between miR-124 and talin 1, miR-124 mimics, miR-124 inhibitors, and talin 1 small interfering RNA (siRNA) were transiently transfected into cancer cell lines, followed by analysis using luciferase reporter assays. Next, to investigate the functions of miR-124 in prostate cancer, we performed cell attachment, migration, and invasion assays. A rescue experiment was also conducted to demonstrate whether miR-124 suppressed cell adhesion and motility by targeting talin 1. Finally, we examined the related signaling pathways of miR-124 and talin 1.
MiR-124 was down-regulated in prostate cancer specimens and cell lines, while talin 1 was over-expressed in prostate cancer specimens and cell lines. These results showed an inverse correlation of miR-124 and talin 1 expression. Similar to talin 1 siRNA, overexpression of miR-124 by transient transfection of mimics led to a significant decrease in talin 1 levels. Luciferase report assays showed that the seed sequence of the talin 1 3'-untranslated region was a target of miR-124. Functional investigations revealed anti-attachment, anti-migration, and invasion-promoting effects of miR-124 in prostate cancer cells. The rescue experiment confirmed that miR-124 exerted its biological functions by targeting talin 1. Finally, we found that miR-124 and talin 1 impaired cellular adhesion and motility through integrins and the focal adhesion kinase/Akt pathway.
Our study demonstrated biological roles and the related mechanism of miR-124 in prostate cancer. The results indicate that talin 1 is very likely a novel player in the anti-metastatic signaling network of miR-124. By down-regulation of talin 1, miR-124 impairs the adhesion, migration, and invasion of prostate cancer cells.
微小RNA是一类参与多种细胞过程的内源性非编码RNA，多年来在癌症研究领域受到广泛研究。在此，我们研究了miR-124在前列腺癌中的功能和机制，miR-124在许多癌症中被认为是一种潜在的肿瘤抑制因子。
利用生物信息学方法，发现踝蛋白1是miR-124的潜在靶点。我们检测了组织标本和细胞系中miR-124和踝蛋白1的表达水平。为了探究miR-124与踝蛋白1之间的关系，将miR-124模拟物、miR-124抑制剂和踝蛋白1小干扰RNA（siRNA）瞬时转染至癌细胞系，随后通过荧光素酶报告基因检测进行分析。接下来，为了研究miR-124在前列腺癌中的功能，我们进行了细胞黏附、迁移和侵袭实验。还进行了一项挽救实验，以证明miR-124是否通过靶向踝蛋白1抑制细胞黏附和运动。最后，我们检测了miR-124和踝蛋白1的相关信号通路。
miR-124在前列腺癌标本和细胞系中表达下调，而踝蛋白1在前列腺癌标本和细胞系中过表达。这些结果表明miR-124与踝蛋白1的表达呈负相关。与踝蛋白1 siRNA类似，通过瞬时转染模拟物过表达miR-124导致踝蛋白1水平显著降低。荧光素酶报告基因检测表明，踝蛋白1 3'非翻译区的种子序列是miR-124的靶点。功能研究揭示了miR-124对前列腺癌细胞具有抗黏附、抗迁移和促进侵袭的作用。挽救实验证实，miR-124通过靶向踝蛋白1发挥其生物学功能。最后，我们发现miR-124和踝蛋白1通过整合素和黏着斑激酶/蛋白激酶B途径损害细胞黏附和运动。
我们的研究证明了miR-124在前列腺癌中的生物学作用及相关机制。结果表明，踝蛋白1很可能是miR-124抗转移信号网络中的一个新成员。通过下调踝蛋白1，miR-124损害前列腺癌细胞的黏附、迁移和侵袭能力。
