转录因子 SP1 诱导的 microRNA-146b-3p 通过调节 FAM107A 促进结直肠癌的进展和转移。

Transcription factor SP1-induced microRNA-146b-3p facilitates the progression and metastasis of colorectal cancer via regulating FAM107A.

机构信息

Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Department of Neurology, Wuhan Brain Hospital, General Hospital of the YANGTZE River Shipping, Wuhan 430015, China.

出版信息

Life Sci. 2021 Jul 15;277:119398. doi: 10.1016/j.lfs.2021.119398. Epub 2021 Apr 5.

DOI:10.1016/j.lfs.2021.119398

PMID:33831429

Abstract

BACKGROUND

Recent studies have provided compelling evidence regarding the association of microRNAs (miRNAs) with the progression and development of tumors. Among the miRNAs, the dysregulation of miR-146b-3p expression has been reported in several cancers, however, its effect on colorectal cancer (CRC) remains unexplored. Many studies have suggested a close correlation between the transcription factor (TF)-miRNA signal and cancer. The present study explored the effects of TF-miR-146b-3p axis on CRC and elucidated its downstream regulatory molecule.

MATERIALS AND METHODS

The expression levels of miR-146b-3p in CRC tissues and cell lines were assessed via quantitative real-time polymerase chain reaction (qRT-PCR). The impact of miR-146b-3p on CRC cell proliferation, migration, and invasion were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell proliferation assay and transwell migration and invasion assay. Additionally, the impact of miR-146b-3p on CRC cell cycle and apoptosis was investigated using flow cytometry. The targets of miR-146b-3p, predicted by miRWalk database, were verified using a dual-luciferase reporter system. The expression levels of TFs were detected using qRT-PCR. The effects of miR-146b-3p and SP1 on FAM107A expression were assessed by performing qRT-PCR and western blotting. Chromatin Immunoprecipitation (ChIP) Assay was performed and JASPAR database was utilized to explore the regulatory relationship between the SP1 and miR-146b-3p.

RESULTS

Increased expression of miR-146b-3p in CRC tissues and cell lines correlated with poor overall survival (OS). Upregulation of miR-146b-3p expression remarkably promoted the proliferation, migration, and invasion of CRC cells and suppressed their apoptosis. Furthermore, SP1 overexpression significantly elevated the miR-146b-3p expression, decreased the FAM107A expression, and promoted the G1/S transition. The miR-146b-3p overexpression also enhanced the effects of SP1 overexpression on CRC cell proliferation, migration, and invasion, whereas miR-146b-3p knockdown led to the opposite results.

CONCLUSION

Mechanistically, miR-146b-3p functions as an oncogene by directly targeting FAM107A. Our results highlight the critical regulatory role played by SP1-induced miR-146b-3p expression in CRC development. Our results suggest that SP1/miR-146b-3p/FAM107A axis may be a potential therapeutic target for CRC.

摘要

背景

最近的研究提供了令人信服的证据，证明 microRNAs（miRNAs）与肿瘤的进展和发展有关。在 miRNAs 中，miR-146b-3p 的表达失调已在几种癌症中报道，然而，其对结直肠癌（CRC）的影响仍未得到探索。许多研究表明转录因子（TF）-miRNA 信号与癌症密切相关。本研究探讨了 TF-miR-146b-3p 轴对 CRC 的影响，并阐明了其下游调节分子。

材料和方法

通过实时定量聚合酶链反应（qRT-PCR）评估 CRC 组织和细胞系中 miR-146b-3p 的表达水平。使用 3-(4,5-二甲基噻唑-2-基）-2,5-二苯基四唑溴盐（MTT）细胞增殖测定和 Transwell 迁移和侵袭测定分析 miR-146b-3p 对 CRC 细胞增殖、迁移和侵袭的影响。此外，通过流式细胞术研究 miR-146b-3p 对 CRC 细胞周期和凋亡的影响。通过 miRWalk 数据库预测 miR-146b-3p 的靶标，并通过双荧光素酶报告系统进行验证。通过 qRT-PCR 检测 TF 的表达水平。通过进行 qRT-PCR 和 Western blot 评估 miR-146b-3p 和 SP1 对 FAM107A 表达的影响。进行染色质免疫沉淀（ChIP）测定，并利用 JASPAR 数据库探索 SP1 和 miR-146b-3p 之间的调节关系。

结果

CRC 组织和细胞系中 miR-146b-3p 的表达增加与总生存期（OS）不良相关。miR-146b-3p 表达的上调显著促进了 CRC 细胞的增殖、迁移和侵袭，并抑制了它们的凋亡。此外，SP1 过表达显著提高了 miR-146b-3p 的表达，降低了 FAM107A 的表达，并促进了 G1/S 期转变。miR-146b-3p 的过表达也增强了 SP1 过表达对 CRC 细胞增殖、迁移和侵袭的影响，而 miR-146b-3p 的敲低则导致相反的结果。