Department of Anorectal, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong 264000, P.R. China.
Department of General Surgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong 264000, P.R. China.
Mol Med Rep. 2019 Nov;20(5):4449-4458. doi: 10.3892/mmr.2019.10717. Epub 2019 Oct 1.
MicroRNAs (miRNAs) play a vital role in the progression of cancer, however, only limited data on miRNAs in rectal cancer are available. The aim of the present study was to investigate whether miR‑195 could inhibit the progression of rectal cancer. The miR‑195 mimic was transfected into 2 types of human rectal cancer cells (SW837 and SW1463). Cell viability and apoptosis were analyzed by Cell Counting Kit‑8 (CCK‑8) assay and flow cytometry, and cell migration and invasion were assessed by scratch test and Transwell assay. The results revealed that insulin‑like growth factor 1 (IGF1) was predicted as a potential target of miR‑195 by Targetscan7.2, and the result was verified by dual‑luciferase reporter assay. The co‑transfection of IGF1 was performed to confirm the underlying mechanism of tumor suppressor of miR‑195 in rectal cancer. The activation of PI3K/AKT signaling was determined by western blotting. The levels of miR‑195 in SW837 and SW1463 cells were revealed to be lower than in human rectal mucosa epithelial cells. After the transfection with miR‑195, the cell viability was decreased, while the apoptosis was significantly increased (SW837: 5.21% vs. 20.96%; SW1463: 4.19% vs. 25.22%). Moreover, cell migration and invasion were significantly inhibited in the mimic group. miR‑195 specifically targeted IGF1, however, the co‑transfection of IGF1 could partially reverse the inhibitory effects of miR‑195 on rectal cancer cells. It was also determined that the phosphorylation of PI3K and AKT were significantly inhibited in the mimic group. The tumor suppressive ability of miR‑195 in rectal cancer cell proliferation and metastasis was mediated by blocking IGF1 expression and inhibiting the PI3K/AKT pathway.
微小 RNA（miRNA）在癌症的进展中起着至关重要的作用，然而，目前关于直肠癌中 miRNA 的数据有限。本研究旨在探讨 miR-195 是否能抑制直肠癌的进展。将 miR-195 模拟物转染入两种人直肠癌细胞（SW837 和 SW1463）中。通过细胞计数试剂盒-8（CCK-8）检测和流式细胞术分析细胞活力和细胞凋亡，通过划痕试验和 Transwell 试验评估细胞迁移和侵袭。结果显示，胰岛素样生长因子 1（IGF1）被 Targetscan7.2 预测为 miR-195 的潜在靶标，双荧光素酶报告基因检测结果验证了这一预测。共转染 IGF1 以证实 miR-195 在直肠癌中的肿瘤抑制作用的潜在机制。通过 Western blot 检测 PI3K/AKT 信号通路的激活情况。结果显示，SW837 和 SW1463 细胞中的 miR-195 水平低于人直肠黏膜上皮细胞。转染 miR-195 后，细胞活力降低，而细胞凋亡明显增加（SW837：5.21%比 20.96%；SW1463：4.19%比 25.22%）。此外，模拟组细胞迁移和侵袭明显受到抑制。miR-195 特异性靶向 IGF1，然而，共转染 IGF1 可以部分逆转 miR-195 对直肠癌细胞的抑制作用。同时还发现，模拟组中 PI3K 和 AKT 的磷酸化明显受到抑制。miR-195 通过阻断 IGF1 表达和抑制 PI3K/AKT 通路抑制直肠癌细胞增殖和转移的肿瘤抑制作用。
