Department of General Surgery, 900 Hospital of the Joint Logistics Supports Force, Fuzhou, 350025, Fujian, China.
Department of Oncology, 900 Hospital of the Joint Logistics Supports Force, No.156 West Second Ring North Road, Gulou District, Fuzhou, 350025, Fujian, China.
Clin Transl Oncol. 2022 Nov;24(11):2166-2174. doi: 10.1007/s12094-022-02869-w. Epub 2022 Jul 4.
This study was designed to explore the role of COPZ1 in breast cancer as well as discuss its specific reaction mechanism.
With the help of RT-qPCR and western blot, the expression of BMI1 and COPZ1 were measured. Then, the proliferation, colony formation and apoptosis were evaluated by CCK-8, colony formation and TUNEL assays, separately. Luciferase reporter assay and ChIP were applied to assess the relative activity of COPZ1 promoter as well as its binding with BMI1. Moreover, western blot was utilized to measure the expression of proliferation-, apoptosis- and autophagy-related proteins.
According to GEPIA2 database, COPZ1 was upregulated in breast cancer tissues and was associated with the poor prognosis (P = 0.03). Results obtained from RT-qPCR and western blot verified that COPZ1 expression was greatly increased at both mRNA and protein levels in breast cancer cells as compared to control cells (P < 0.05 or P < 0.001). COPZ1 knockdown inhibited the proliferation, induced the autophagy and promoted the apoptosis of breast cancer cells. HumanTFDB predicted the binding sites of BMI1 and COPZ1. The increased relative luciferase activity of COPZ1 promoter following BMI1 overexpression (P < 0.001) and the binding of BMI1 with COPZ1 promoter indicated that BMI1 could activate COPZ1. Further experiments suggested that the effects of COPZ1 knockdown on the proliferation, apoptosis and autophagy of breast cancer cells were reversed by BMI1 overexpression, implying that BMI1 promoted the proliferation and repressed the autophagy of breast cancer cells via activating COPZ1.
To sum up, BMI1 exhibited promotive effects on the malignant progression of breast cancer through the activation of COPZ1. These findings might offer a preliminary theoretical basis for COPZ1 participation in autophagy in breast cancer cells.
本研究旨在探讨 COPZ1 在乳腺癌中的作用，并探讨其具体反应机制。
利用 RT-qPCR 和 Western blot 测量 BMI1 和 COPZ1 的表达。然后，通过 CCK-8、集落形成和 TUNEL 测定分别评估增殖、集落形成和细胞凋亡。应用荧光素酶报告基因和 ChIP 评估 COPZ1 启动子的相对活性及其与 BMI1 的结合。此外，Western blot 用于测量增殖、凋亡和自噬相关蛋白的表达。
根据 GEPIA2 数据库，COPZ1 在乳腺癌组织中上调，并与不良预后相关（P = 0.03）。RT-qPCR 和 Western blot 的结果验证了与对照细胞相比，乳腺癌细胞中 COPZ1 的表达在 mRNA 和蛋白水平上均显著增加（P < 0.05 或 P < 0.001）。COPZ1 敲低抑制乳腺癌细胞的增殖，诱导自噬并促进细胞凋亡。HumanTFDB 预测了 BMI1 和 COPZ1 的结合位点。BMI1 过表达后 COPZ1 启动子的相对荧光素酶活性增加（P < 0.001），以及 BMI1 与 COPZ1 启动子的结合表明 BMI1 可以激活 COPZ1。进一步的实验表明，通过 BMI1 过表达，COPZ1 敲低对乳腺癌细胞增殖、凋亡和自噬的影响被逆转，这表明 BMI1 通过激活 COPZ1 促进乳腺癌细胞的增殖并抑制自噬。
总之，BMI1 通过激活 COPZ1 对乳腺癌的恶性进展表现出促进作用。这些发现可能为 COPZ1 参与乳腺癌细胞自噬提供初步的理论基础。
