ABSTRACT

Prostate cancer (PC) is the most common malignancy in men. As per recent findings, microRNA-300 (miR-300) were found to be overexpressed in numerous types of cancers. In this study, we aimed to explore the effects of miR-300 on the adhesion, invasion, and migration of PC cells by targeting Disabled 1 (DAB1). Firstly, the regulatory role of miRNAs on DAB1 was predicted by screening PC-related differentially expressed genes (DEGs). Immunohistochemistry was applied to determine the positive protein expression of DAB1, after which the target relationship between miR-300 and DAB1 was examined. Loss-of-function and gain-of-function experiments were conducted to determine cell proliferation, adhesion, migration, invasion capability, and cell cycle of PC cells. Our data illustrated that DAB1 had a low expression, while miR-300 was expressed at a relatively high level in PC tissues. Moreover, our clinicopathological analysis revealed that there was a correlation between miR-300 and tumor, node, metastases stage, Gleason score, and lymph node metastasis of PC patients. DAB1 was also found to be poorly expressed in PC based on the findings from the microarray analysis. The results from dual-luciferase reporter gene assay corroborated that miR-300 interacts with DAB1. Importantly, overexpression of miR-300 and/or si-DAB1 resulted in the enhancement of RAC1, MMP2, MMP9, CyclinD1, and CyclinE expressions, whereas the expression of DAB1 and Rap was reduced in PC cells, thus suggesting that down-regulated miR-300 suppressed proliferation, adhesion, migration, and invasion of PC cells. Collectively, our results provided evidence that down-regulation of miR-300 inhibits the adhesion, migration, and invasion of PC cells.

摘要

前列腺癌 (PC) 是男性最常见的恶性肿瘤。根据最近的研究结果，发现 microRNA-300 (miR-300) 在多种癌症中过度表达。在本研究中，我们旨在通过靶向 Disabled 1 ( DAB1 )来探索 miR-300 对 PC 细胞粘附、侵袭和迁移的影响。首先，通过筛选 PC 相关差异表达基因 (DEGs) 来预测miRNAs 对DAB1的调控作用。应用免疫组化法检测DAB1的阳性蛋白表达，进而确定miR-300与DAB1的靶标关系被检查了。进行功能丧失和功能获得实验以确定PC细胞的细胞增殖、粘附、迁移、侵袭能力和细胞周期。我们的数据表明DAB1的表达水平较低，而 miR-300 在 PC 组织中的表达水平相对较高。此外，我们的临床病理分析显示，miR-300 与 PC 患者的肿瘤、淋巴结、转移分期、Gleason 评分和淋巴结转移之间存在相关性。根据微阵列分析的结果，还发现DAB1在 PC 中表达不佳。双荧光素酶报告基因测定的结果证实了 miR-300 与DAB1相互作用。重要的是，miR-300 和/或 si- DAB1 的过表达导致 RAC1、MMP2、MMP9、CyclinD1 和 CyclinE 表达增强，而DAB1和 Rap 在 PC 细胞中的表达降低，从而表明下调的 miR-300 抑制了 PC 的增殖、粘附、迁移和侵袭细胞。总的来说，我们的结果提供了证据，表明 miR-300 的下调抑制了 PC 细胞的粘附、迁移和侵袭。