The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou 510630 , Guangdong Province, China; Department of Emergency, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, Liaoning Province, China.
The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou 510630 , Guangdong Province, China; The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000 , Liaoning Province, China.
Tissue Cell. 2022 Aug;77:101817. doi: 10.1016/j.tice.2022.101817. Epub 2022 May 7.
In digestive system, colorectal cancer (CRC) is a common malignant tumor. The phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of the rapamycin (PI3K/AKT/mTOR) signaling pathway plays a central role in CRC, and the aberrant activation of this pathway is associated with tumorigenesis. We aimed to explore the role of Rho GTPase activating protein 9 (ARHGAP9) in the progression of CRC as well as its regulatory effects on the PI3K/AKT/mTOR pathway.
The expression of ARHGAP9 in CRC tumor tissues and cell lines were detected using reverse transcription-quantitative PCR (qRT-PCR). 5-ethynyl-2'-deoxyuridine (EdU) assay was applied to test the cell proliferation. Cell migration and invasion were both assessed through transwell assay. Xenograft mouse models were constructed to explore the effects of ARHGAP9 on CRC in vivo. The expressions of PI3K/AKT/mTOR-activating factors and epithelial-mesenchymal transition (EMT)-related factors were all determined using western blot. LY294002 was employed to block PI3K/AKT/mTOR pathway in CRC cells.
The expression of ARHGAP9 was down-regulated in CRC tumor tissues and cell lines when compared to normal tissues and cells. The over-expression of ARHGAP9 inhibited cell proliferation, invasion, migration and EMT in CRC cell lines while the knockdown of ARHGAP9 promoted them. In addition, ARHGAP9 up-regulation inhibited the activation of PI3K/AKT/mTOR signaling pathway in CRC cell lines while ARHGAP9 down-regulation led to an opposite effect. The over-expression of ARHGAP9 suppressed CRC tumor growth in vivo. When the PI3K/AKT/mTOR pathway was blocked in CRC cells, the effects of ARHGAP9 knockdown on cell proliferation, migration, invasion and EMT were all overturned.
ARHGAP9 inhibited the malignant phenotypes of CRC cells via interdicting PI3K/AKT/mTOR signaling pathway.
在消化系统中，结直肠癌（CRC）是一种常见的恶性肿瘤。磷脂酰肌醇 3-激酶/蛋白激酶 B/雷帕霉素靶蛋白（PI3K/AKT/mTOR）信号通路在 CRC 中起着核心作用，该通路的异常激活与肿瘤发生有关。我们旨在探讨 Rho GTP 酶激活蛋白 9（ARHGAP9）在 CRC 进展中的作用及其对 PI3K/AKT/mTOR 通路的调节作用。
采用逆转录定量 PCR（qRT-PCR）检测 CRC 肿瘤组织和细胞系中 ARHGAP9 的表达。采用 5-乙炔基-2'-脱氧尿苷（EdU）检测法检测细胞增殖。通过 Transwell 测定法检测细胞迁移和侵袭。构建异种移植小鼠模型以探讨 ARHGAP9 对 CRC 的体内作用。采用 Western blot 检测 PI3K/AKT/mTOR 激活因子和上皮-间充质转化（EMT）相关因子的表达。采用 LY294002 阻断 CRC 细胞中的 PI3K/AKT/mTOR 通路。
与正常组织和细胞相比，CRC 肿瘤组织和细胞系中 ARHGAP9 的表达下调。ARHGAP9 的过表达抑制 CRC 细胞系中的细胞增殖、侵袭、迁移和 EMT，而 ARHGAP9 的敲低则促进这些过程。此外，ARHGAP9 的上调抑制 CRC 细胞系中 PI3K/AKT/mTOR 信号通路的激活，而 ARHGAP9 的下调则导致相反的效果。ARHGAP9 的过表达抑制体内 CRC 肿瘤的生长。当 CRC 细胞中的 PI3K/AKT/mTOR 通路被阻断时，ARHGAP9 敲低对细胞增殖、迁移、侵袭和 EMT 的影响均被推翻。
ARHGAP9 通过抑制 PI3K/AKT/mTOR 信号通路抑制 CRC 细胞的恶性表型。
