Department of Gastrointestinal Surgery, The First People's Hospital of Lianyungang, The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, China.
J BUON. 2021 Mar-Apr;26(2):528-535.
Colorectal carcinoma (CRC) ranks third in incidence but second in mortality worldwide, ascertaining the pathogenesis of CRC is crucial for its treatment. Accumulating studies have shown that E2F1 is a key regulator in CRC progression, which regulates the transcription of genes engaged in DNA replication, mitosis and survival of cancer patients, however, the mechanism of these processes is not fully elucidated.
Here, we determined E2F1 expression in clinical CRC specimens by TCGA database analysis, Microarray immunohistochemical technique and Western blot, respectively. The expression of E2F1 was elevated in CRC tumor tissues, and the patients' total survival time was associated with the level of E2F1. Then the prediction software and meta-analysis were used to predict the miRNAs targeting E2F1. RT-qPCR, TCGA analysis and in situ hybridization experiments were utilized to determine the decreased miR-326 expression in CRC tumor tissues. Luciferase and Western blot assays determined that miR-326 directly targeted E2F1 in CRC cells. Next, CCK8, flow cytometry, Transwell and wound healing assays were used to determine the biological function of miR-326-E2F1 axis in vitro.
miR-326 overexpression significantly inhibited the viability, invasion and migration and promoted the apoptosis of CRC cells, but overexpression of both E2F1 and miR-326 in turn increased cell viability, invasion and migration and decreased cell apoptosis.
This study demonstrates the significant roles of miR-326-E2F1 in CRC progression and may represent a potential target for CRC therapy.
结直肠癌（CRC）在全球的发病率排名第三，但死亡率排名第二，因此确定 CRC 的发病机制对于其治疗至关重要。越来越多的研究表明，E2F1 是 CRC 进展的关键调节因子，它调节参与 DNA 复制、有丝分裂和癌症患者存活的基因的转录，然而，这些过程的机制尚未完全阐明。
在这里，我们通过 TCGA 数据库分析、微阵列免疫组织化学技术和 Western blot 分别确定了临床 CRC 标本中 E2F1 的表达。E2F1 在 CRC 肿瘤组织中表达上调，患者的总生存时间与 E2F1 水平相关。然后使用预测软件和荟萃分析预测靶向 E2F1 的 miRNAs。RT-qPCR、TCGA 分析和原位杂交实验用于确定 CRC 肿瘤组织中 miR-326 的表达降低。荧光素酶和 Western blot 测定表明 miR-326 在 CRC 细胞中直接靶向 E2F1。接下来，CCK8、流式细胞术、Transwell 和划痕愈合实验用于体外确定 miR-326-E2F1 轴的生物学功能。
miR-326 的过表达显著抑制了 CRC 细胞的活力、侵袭和迁移，并促进了细胞凋亡，而 E2F1 和 miR-326 的共表达则反过来增加了细胞活力、侵袭和迁移，并减少了细胞凋亡。
本研究表明 miR-326-E2F1 在 CRC 进展中具有重要作用，可能代表 CRC 治疗的潜在靶点。
