背景:在全球范围内,女性乳腺癌是癌症死亡的第五大原因。迫切需要探索乳腺癌增殖和转移的分子机制。
方法:TCGA数据库分析用于分析乳腺癌和正常样本中的基因表达以及基因表达与预后之间的关联。免疫组织化学染色,采用qPCR和蛋白质印迹法检测基因表达。进行细胞功能检测以研究TEX19和CDK4异常表达对细胞增殖的影响。迁移,凋亡,细胞周期,和殖民地的形成。采用生物信息学分析方法结合CHX跟踪实验和Co-IP实验对TEX19的下游分子和调控机制进行筛选和验证。此外,建立裸鼠皮下肿瘤发生模型。
结果:TEX19在乳腺癌中显著上调,TEX19水平与肿瘤侵袭和预后有关。TEX19敲低抑制乳腺癌细胞的增殖和迁移,细胞凋亡增加,并在G2期阻断细胞周期。此外,TEX19抑制体内肿瘤的生长。机械上,TEX19上调CDK4蛋白水平,这取决于E3泛素连接酶SKP2。具体来说,TEX19敲低和SKP2蛋白过表达破坏了CDK4蛋白的稳定性并增强了CDK4蛋白的泛素化。此外,CDK4敲低抑制细胞增殖,迁移,和乳腺癌细胞的集落形成,并减轻TEX19过表达对乳腺癌细胞增殖和迁移的促进作用。
结论:TEX19和CDK4在乳腺癌中上调,TEX19通过影响SKP2介导的CDK4的泛素化,从而增加CDK4蛋白的水平,从而促进乳腺癌的进展。
BACKGROUND: Globally, breast cancer in women is the fifth leading cause of cancer death. There is an urgent need to explore the molecular mechanism of breast cancer proliferation and metastasis.
METHODS: TCGA database analysis was used to analyze genes expression in breast cancer and normal samples and the association between gene expression and prognosis. Immunohistochemical staining, qPCR and western blotting was sued to detected gene expression. The cell function tests were conducted to investigate the effects of TEX19 and
CDK4 with abnormal expression on cell proliferation, migration, apoptosis, cell cycle, and colony formation. Bioinformatics analysis methods combined with CHX tracking experiment and Co-IP experiment were performed to screen and verify the downstream molecule and regulatory mechanism of TEX19. Besides, subcutaneous tumorigenesis model in nude mice was constructed.
RESULTS: TEX19 was significantly upregulated in breast cancer, and the TEX19 level was related to tumor invasion and prognosis. TEX19 knockdown inhibited the proliferation and migration of breast cancer cells, increased cell apoptosis, and blocked the cell cycle in the G2 phase. Besides, TEX19 suppressed the growth of tumors in the body. Mechanically, TEX19 upregulated the level of
CDK4 protein, which depended on the E3 ubiquitin ligase SKP2. Specifically, TEX19 knockdown and SKP2 protein overexpression destroyed the stability of
CDK4 protein and enhanced the ubiquitination of
CDK4 protein. Additionally, CDK4 knockdown inhibited the proliferation, migration, and colony formation of breast cancer cells, and alleviated the promotion of TEX19 overexpression on the proliferation and migration of breast cancer cell.
CONCLUSIONS: TEX19 and CDK4 were upregulated in breast cancer, and TEX19 increased the level of
CDK4 protein by influencing SKP2-mediated ubiquitination of
CDK4, thereby promoting the progression of breast cancer.