Department of General Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai, P.R. China.
Division of Gastroenterology and Hepatology, Digestive Disease Institute, Tongji Hospital, Tongji University School of Medicine, Shanghai, P.R. China.
Int J Med Sci. 2017 Aug 8;14(10):937-942. doi: 10.7150/ijms.19565. eCollection 2017.
Better understanding the molecular mechanisms responsible for the genesis and progression of colorectal cancer would help advance the novel therapeutics. miR-224 has been identified to be elevated in colorectal cancer and promote human colorectal cancer cell line SW480 proliferation and invasion. However, the effect of miRNAs on cancer cell proliferation could be significantly changeable among different cell lines. HCT116 is a commonly used cell line for colorectal cancer study and the target gene responsible for the function of miR-224 in its proliferation is unclear. miR-224 expression was determined by quantitative reverse transcription polymerase chain reactions (PCRs) in human colorectal cancer tissues compared with their corresponding matched peritumoral tissues. HCT116 cell viability and cell proliferation were determined by CCK-8, EdU incorporation assays and flow cytometry for cell cycle. Target gene of miR-224 was confirmed by Western blots and siRNA for Smad4. miR-224 was significantly increased by 29.49 fold in colorectal cancer tissues compared with their corresponding matched peritumoral tissues based on 12 colorectal cancer patients. miR-224 mimic significantly increased HCT116 cell viability, EdU positive cells rate, and decreased G1 phase cell population and increased S phase cell population. miR-224 inhibitor had opposite effects. Smad4 could be negatively regulated by miR-224 in HCT116 cells and was responsible for its effects in proliferation. miR-224 mediates HCT116 cell proliferation by targeting Smad4.
更好地了解导致结直肠癌发生和进展的分子机制将有助于推进新的治疗方法。miR-224 已被确定在结直肠癌中升高，并促进人结直肠癌细胞系 SW480 的增殖和侵袭。然而，miRNAs 对不同细胞系中癌细胞增殖的影响可能会有很大的变化。HCT116 是一种常用于结直肠癌研究的细胞系，miR-224 在其增殖中的靶基因尚不清楚。通过定量逆转录聚合酶链反应（PCRs）在人结直肠癌组织与相应的癌旁组织中比较 miR-224 的表达。通过 CCK-8、EdU 掺入测定和流式细胞术检测细胞周期来确定 HCT116 细胞活力和增殖。通过 Western blot 和 Smad4 的 siRNA 来验证 miR-224 的靶基因。基于 12 例结直肠癌患者，miR-224 在结直肠癌组织中比相应的癌旁组织显著增加了 29.49 倍。miR-224 模拟物显著增加了 HCT116 细胞活力、EdU 阳性细胞率，减少了 G1 期细胞群体，增加了 S 期细胞群体。miR-224 抑制剂则有相反的效果。miR-224 可以在 HCT116 细胞中负调控 Smad4，并负责其增殖作用。miR-224 通过靶向 Smad4 介导 HCT116 细胞增殖。
