Department of Medical Biotechnology, Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute (CHRI), Chettinad Academy of Research and Education (CARE), Kelambakkam, Chennai 603103, Tamil Nadu, India.
Microrna. 2020;9(5):354-362. doi: 10.2174/2211536609666201209152228.
MicroRNA, a non-coding RNA molecule plays a vital role in post transcriptional gene expression. MicroRNA-122, a liver specific microRNA was found to be downregulated in liver cancer and is associated with hepatocarcinogenesis. Being confirmed as tumor suppressor microRNA in liver carcinogenesis, we aimed to study the expression of microRNA-122 in colon cancer cell lines and the role of microRNA-122 in cell proliferation, invasion and migration of colon cancer cells.
The expression of microRNA-122 is quantified using qRT-PCR by TaqMan universal primers. Colon cancer cell lines (SW480, SW620, HCT116) were transfected with microRNA-122 mimic and further studied for determining cell proliferation using CCK-8 kit, migration using Scratch assay, invasion using Transwell assay, apoptosis using Annexin-V FITC kit, and also gene expression.
Gene expression results displayed decreased expression of microRNA-122 in colon cancer cell lines. Transfection with microRNA-122 mimics impaired the cell proliferation and migration compared with control. FACS analysis confirmed that the percentage of microRNA-122 mimic transfected cells undergoing early apoptosis was increased. Gene expression of AEG-1, PI3K, CDK6, and PCNA were found to be downregulated in microRNA-122 overexpressed cells. Migratory and invasion potential of transfected cells was lessened in mimic transfected cells compared to control.
The overexpression of microRNA-122 inhibited the cellular proliferation, migration, invasion and increased percentage of cells undergoing early apoptosis, suggesting its anti-cancer potential. Studying the role of microRNA-122 and its interactions with oncogenes might pave the way to understand the underlying mechanism in colon cancer.
微小 RNA 是一种非编码 RNA 分子，在转录后基因表达中起着至关重要的作用。研究发现，微小 RNA-122（一种肝脏特异性微小 RNA）在肝癌中表达下调，与肝癌发生有关。微小 RNA-122 在肝癌发生中被确认为肿瘤抑制微小 RNA，我们旨在研究微小 RNA-122 在结肠癌细胞系中的表达及其在结肠癌细胞增殖、侵袭和迁移中的作用。
使用 TaqMan 通用引物通过 qRT-PCR 定量检测微小 RNA-122 的表达。用微小 RNA-122 模拟物转染结肠癌细胞系（SW480、SW620、HCT116），进一步用 CCK-8 试剂盒测定细胞增殖，用划痕实验测定迁移，用 Transwell 测定侵袭，用 Annexin-V FITC 试剂盒测定凋亡，并进行基因表达分析。
基因表达结果显示结肠癌细胞系中微小 RNA-122 的表达降低。与对照相比，转染微小 RNA-122 模拟物可损害细胞增殖和迁移。FACS 分析证实，经微小 RNA-122 模拟物转染的细胞中早期凋亡的细胞比例增加。在微小 RNA-122 过表达细胞中，AEG-1、PI3K、CDK6 和 PCNA 的基因表达下调。与对照相比，转染细胞的迁移和侵袭潜力在模拟物转染细胞中降低。
微小 RNA-122 的过表达抑制了细胞增殖、迁移和侵袭，并增加了早期凋亡细胞的比例，提示其具有抗癌潜力。研究微小 RNA-122 的作用及其与癌基因的相互作用可能为理解结肠癌的潜在机制铺平道路。
