Department of Gastroenterology, The Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, China.
Eur Rev Med Pharmacol Sci. 2022 Mar;26(6):2049-2056. doi: 10.26355/eurrev_202203_28353.
The aim of this study was to investigate the effects of micro ribonucleic acid (miR)-490-5p on the proliferation and apoptosis of colon cancer cells, and to explore its potential mechanism.
The mRNA expression of miR-490-5p in 30 pairs of colon cancer tissues and adjacent normal tissues was detected via reverse transcription-polymerase chain reaction (RT-PCR). Human colon cancer SW480 cell lines were cultured in vitro and divided into Control group and miR-490-5p overexpression group (miR-490-5p mimic group). The nonsense sequence and miR-490-5p mimic were transfected using liposome transfection technique into colon cancer cells in control group and miR-490-5p mimic group, respectively. Cell proliferation and apoptosis in each group were then observed. At the same time, the effect of miR-490-5p on the growth of colon cancer in vivo was explored using subcutaneous tumorigenesis assay. The protein expressions of extracellular signal-regulated kinase (ERK)1/2 signaling pathway and cyclin-dependent kinase 1 (CDK1) were determined via Western blotting. Furthermore, immunohistochemical staining was performed to verify the protein expression of CDK1 in vivo.
The expression of miR-490-5p in colon cancer tissues was significantly lower than that in adjacent normal tissues (p<0.05). After transfection with miR-490-5p mimic in vitro, EdU staining and colony formation assay showed that the proliferation ability of SW480 cells was significantly weakened (p<0.05). Meanwhile, the number of colonies in miR-490-5p mimic group was markedly less than that in Control group (p<0.05). The results of Western blotting revealed that overexpression of miR-490-5p remarkably up-regulated the Bax/Bcl-2 and C-Caspase3/T-Caspase3 ratios in cancer cells (p<0.05). Subsequent results indicated that the subcutaneous tumorigenesis of colon cancer cells was markedly inhibited by overexpression of miR-490-5p (p<0.05). According to the results of Western blotting, the activation of ERK signaling pathway and the protein expression of CDK1 were significantly suppressed by overexpression of miR-490-5p (p<0.05). In vivo experiments further revealed that the protein expression of CDK1 in colon cancer tissues increased significantly (p<0.05).
MiR-490-5p was found lowly expressed in colon cancer patients. In addition, overexpression of miR-490-5p inhibited the proliferation and promoted the apoptosis of colon cancer cells via down-regulating CDK1 both in vitro and in vivo.
本研究旨在探讨微小 RNA（miR）-490-5p 对结肠癌细胞增殖和凋亡的影响，并探讨其潜在机制。
采用逆转录-聚合酶链反应（RT-PCR）检测 30 对结肠癌组织和相邻正常组织中 miR-490-5p 的 mRNA 表达。体外培养人结肠癌细胞 SW480 系，并分为对照组和 miR-490-5p 过表达组（miR-490-5p 模拟组）。采用脂质体转染技术分别将无意义序列和 miR-490-5p 模拟物转染至对照组和 miR-490-5p 模拟组的结肠癌细胞中。然后观察各组细胞的增殖和凋亡情况。同时，通过皮下肿瘤生成实验探讨 miR-490-5p 对体内结肠癌生长的影响。采用 Western blot 检测细胞外信号调节激酶（ERK）1/2 信号通路和周期蛋白依赖性激酶 1（CDK1）的蛋白表达。此外，采用免疫组织化学染色法验证体内 CDK1 的蛋白表达。
miR-490-5p 在结肠癌组织中的表达明显低于相邻正常组织（p<0.05）。体外转染 miR-490-5p 模拟物后，EdU 染色和集落形成实验显示 SW480 细胞的增殖能力明显减弱（p<0.05）。同时，miR-490-5p 模拟组的集落数明显少于对照组（p<0.05）。Western blot 结果显示，过表达 miR-490-5p 可显著上调癌细胞中 Bax/Bcl-2 和 C-Caspase3/T-Caspase3 比值（p<0.05）。后续结果表明，过表达 miR-490-5p 可显著抑制结肠癌细胞的皮下肿瘤生成（p<0.05）。根据 Western blot 结果，过表达 miR-490-5p 可显著抑制 ERK 信号通路的激活和 CDK1 的蛋白表达（p<0.05）。体内实验进一步显示，结肠癌组织中 CDK1 的蛋白表达明显增加（p<0.05）。
miR-490-5p 在结肠癌患者中表达水平较低。此外，miR-490-5p 过表达可通过下调 CDK1 来抑制结肠癌细胞的增殖并促进其凋亡，无论是在体外还是体内。
