Li Ning, Xu Jianzhong, Yan Xi, Liu Qing, Zhang Mingqi
Department of Breast Surgery, Changzhi People's Hospital, Changzhi, 046000, China.
Department of Pharmacy, Changzhi People's Hospital, Changzhi, 046000, China.
Cell Biochem Biophys. 2024 Sep;82(3):2205-2216. doi: 10.1007/s12013-024-01327-4. Epub 2024 May 30.
To explore the molecular mechanisms of tumor-associated calcium signal transduction factor 2 (TROP2) affecting the occurrence and development of triple-negative breast cancer (TNBC).
The TCGA database, immunohistochemical staining, and qRT-PCR were used to analyze the expression of TROP2 in TNBC tissues and cells. The protein expressions of TROP2 and inositol 1,4,5-trisphosphate receptor (IPR) after TROP2 knockdown were detected by western blot (WB). Cell proliferation was detected by CCK8 and colony formation assay, Annexin V-APC/PI flow cytometry was used to detect apoptosis, and intracellular calcium ion (Ca) was detected by flow cytometry with Fura 2-AM fluorescent probe. Finally, the morphological changes of the endoplasmic reticulum (ER) were observed by transmission electron microscopy, and the expression of ER stress (ERS)-related proteins was detected by WB and immunofluorescence staining.
TROP2 was up-regulated in TNBC tumor tissues and cells. Silencing TROP2 decreased the proliferation rate and clone formation number, and increased the apoptosis rate and the Ca level in TNBC cells. These phenomena were reversed after the addition of 2-APB. In addition, after TROP2 knockdown, the expressions of IPR and ERS-related proteins were up-regulated, the ER was cystic dilated, and ERS was activated. And the addition of 2-APB significantly inhibited the activation of ERS induced by TROP2 knockdown.
TROP2 regulated the proliferation and apoptosis of TNBC cells through a Ca-dependent ERS signaling pathway.
探讨肿瘤相关钙信号转导因子2（TROP2）影响三阴性乳腺癌（TNBC）发生发展的分子机制。
利用TCGA数据库、免疫组织化学染色和qRT-PCR分析TROP2在TNBC组织和细胞中的表达。通过蛋白质免疫印迹法（WB）检测TROP2敲低后TROP2和肌醇1,4,5-三磷酸受体（IPR）的蛋白表达。采用CCK8法和集落形成实验检测细胞增殖，用Annexin V-APC/PI流式细胞术检测细胞凋亡，并用Fura 2-AM荧光探针通过流式细胞术检测细胞内钙离子（Ca）。最后，通过透射电子显微镜观察内质网（ER）的形态变化，并用WB和免疫荧光染色检测ER应激（ERS）相关蛋白的表达。
TROP2在TNBC肿瘤组织和细胞中上调。沉默TROP2可降低TNBC细胞的增殖率和克隆形成数，并增加细胞凋亡率和Ca水平。添加2-APB后这些现象得到逆转。此外，TROP2敲低后，IPR和ERS相关蛋白的表达上调，ER呈囊性扩张，ERS被激活。添加2-APB可显著抑制TROP2敲低诱导的ERS激活。
TROP2通过Ca依赖的ERS信号通路调节TNBC细胞的增殖和凋亡。
