Institute of Clinical Medicine College, Guangzhou University of Chinese Medicine, Guangzhou, China.
Institute of Brain Science and Brain-Like Intelligence, Linyi People's Hospital, Linyi, China.
Cancer Med. 2023 Mar;12(5):5889-5907. doi: 10.1002/cam4.5381. Epub 2022 Oct 25.
Gliomas are a group of primary intracranial tumors with high morbidity and mortality. The previous researches indicated a crucial role of CKS2 (cyclin-dependent kinases regulatory subunit 2) in hepatocellular carcinoma and breast cancer; however, little is known about the molecular mechanism of CKS2 in the tumorigenesis and epithelial-mesenchymal transition-like (EMT) process in glioma.
Datasets for bioinformatics analysis were obtained from the GEO, TCGA and CGGA databases. qRT-PCR, western blotting (WB), and immunohistochemistry (IHC) assays were used to investigate the expression patterns of CKS2 among glioma and brain tissues. Glioma cells were transfected with small interfering RNA/overexpression plasmid against CKS2, then clone formation assay, CCK-8, wound healing, Transwell assay, and flow cytometry were performed to detect changes in cell viability, invasiveness, and the apoptosis rate. Markers of cell invasion, apoptosis, EMT and TGFβ/SMAD signaling were evaluated by WB and immunofluorescence (IF) assays.
We found that CKS2 overexpression correlates with poor prognosis in human glioma and knockdown of CKS2 could inhibit cell proliferation, migration, invasion, and induced apoptosis in glioma cells. Besides, we also found that knockdown of CKS2 could reverse the EMT process via modulating EMT-related molecules. Glioma cells with overexpression of CKS2 were constructed to confirmed the fact that CKS2 induced nucleocytoplasmic translocation of SMAD2/3 and activated TGFβ/SMAD pathway, then upregulated its downstream targets expression, while inhibition of TGFβ/SMAD (by TGFβ inhibitor LY2157299 or SMAD4 siRNA) could reverse the tumor-promoting effects and malignant phenotype caused by CKS2 overexpression.
We identified CKS2 as a critical contributor to the gliomagenesis, which might provide a novel therapeutic target for inhibiting the spread and infiltration of glioma.
神经胶质瘤是一组具有高发病率和死亡率的原发性颅内肿瘤。先前的研究表明 CKS2（细胞周期蛋白依赖性激酶调节亚基 2）在肝癌和乳腺癌中具有重要作用；然而，CKS2 在神经胶质瘤的肿瘤发生和上皮-间充质转化样（EMT）过程中的分子机制知之甚少。
从 GEO、TCGA 和 CGGA 数据库中获取生物信息学分析数据集。使用 qRT-PCR、western blot（WB）和免疫组织化学（IHC）检测 CKS2 在神经胶质瘤和脑组织中的表达模式。用 CKS2 的小干扰 RNA/过表达质粒转染神经胶质瘤细胞，然后进行克隆形成试验、CCK-8、划痕愈合、Transwell 试验和流式细胞术，检测细胞活力、侵袭性和细胞凋亡率的变化。通过 WB 和免疫荧光（IF）检测细胞侵袭、凋亡、EMT 和 TGFβ/SMAD 信号转导的标志物。
我们发现 CKS2 的过表达与人类神经胶质瘤的不良预后相关，而 CKS2 的敲低可抑制神经胶质瘤细胞的增殖、迁移、侵袭，并诱导其凋亡。此外，我们还发现 CKS2 的敲低可通过调节 EMT 相关分子逆转 EMT 过程。构建 CKS2 过表达的神经胶质瘤细胞以证实 CKS2 诱导 SMAD2/3 的核质易位并激活 TGFβ/SMAD 通路，进而上调其下游靶基因的表达，而 TGFβ/SMAD（通过 TGFβ 抑制剂 LY2157299 或 SMAD4 siRNA）的抑制可逆转 CKS2 过表达引起的促肿瘤作用和恶性表型。
我们确定 CKS2 是神经胶质瘤发生的关键贡献者，这可能为抑制神经胶质瘤的扩散和浸润提供新的治疗靶点。
