Li Dan, Guo Yuting, Tian She, Zhu Changhao, Sun Chengyi
Key Laboratory of Hepatobiliary and Pancreatic Surgery and Guizhou Medical University, Guiyang, China.
Department of Hepatic-Biliary-Pancreatic Surgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, China.
J Cancer. 2022 Apr 4;13(7):2200-2212. doi: 10.7150/jca.69617. eCollection 2022.
Pancreatic cancer is one of the most aggressive malignancies globally, with no improvement in the cure rates yet.Caveolin-2 (CAV2) has been repeatedly reported to play an important role in cellular transport and signalling and in exhibiting a pro-oncogenic response in a variety of tumours, although its specific action mechanisms in pancreatic cancer are not well documented. MiRNA is recognized as a therapeutic target for a variety of tumours, making it an important regulator of the Wnt/β-catenin signalling pathway. MiR-4723/Wnt7A constitutes an oncogenic signalling axis in pancreatic cancer by targeting and inhibiting Wnt7A through the activation of MiR4723, but its molecular action mechanism remains unexplored. Therefore, in the present study, we investigated the effect of CAV2 on the MiR-4723/Wnt7A pathway and its action mechanism. We employed TCGA, the GEO database for bioinformatics analysis, cell proliferation assay, wound healing assay, Transwell assay, colony-forming assay, qRT-PCR, and Western blotting to validate the cancer-promoting role of CAV2 in pancreatic cancer and to determine its potential target WNT7A. We then explored CAV2 as a positive regulator of the Wnt7A/β-catenin pathway through immunofluorescence assay, qRT-PCR, and Western blotting. Database analyses, CCK-8 and qRT-PCR revealed that MiR-4723 is an oncogene in pancreatic cancer. Luciferase assay and qRT-PCR revealed that MiR-4723 is a negative regulator of the Wnt7A/β-catenin pathway. To investigate the mechanism of CAV2 action on MiR-4723/Wnt7A, we detected the gene expression of CAV2 through qRT-PCR after MiR-4723 overexpression. Several genes related to endocytosis and epithelial-mesenchymal transition (EMT) were subsequently analysed through immunofluorescence, Western blotting, and qRT-PCR. Overexpression of CAV2 promotes invasion, migration, cloning and metastasis of pancreatic cancer cells. Overexpression of MiR-4723 inhibits CAV2 expression. Here, we are the first to demonstrate that CAV2 exerts a pro-carcinogenic effect on pancreatic cancer through the activation of the Wnt7A/β-catenin signalling pathway. CAV2 can regulate the MiR-4723/Wnt7A signalling axis in pancreatic cancer cell lines by inhibiting endocytosis and promoting EMT, thereby fulfilling the mechanism pro-carcinogenic effects.
胰腺癌是全球最具侵袭性的恶性肿瘤之一，治愈率至今仍未提高。尽管小窝蛋白2（CAV2）在胰腺癌中的具体作用机制尚未完全阐明，但已有多次报道称其在细胞运输和信号传导中发挥重要作用，并在多种肿瘤中表现出促癌反应。微小RNA（miRNA）被认为是多种肿瘤的治疗靶点，是Wnt/β-连环蛋白信号通路的重要调节因子。MiR-4723/Wnt7A通过激活MiR4723靶向抑制Wnt7A，在胰腺癌中构成致癌信号轴，但其分子作用机制仍未被探索。因此，在本研究中，我们研究了CAV2对MiR-4723/Wnt7A通路的影响及其作用机制。我们利用TCGA、GEO数据库进行生物信息学分析，通过细胞增殖试验、伤口愈合试验、Transwell试验、集落形成试验、qRT-PCR和蛋白质免疫印迹法来验证CAV2在胰腺癌中的促癌作用，并确定其潜在靶点WNT7A。然后，我们通过免疫荧光试验、qRT-PCR和蛋白质免疫印迹法探索CAV2作为Wnt7A/β-连环蛋白通路的正向调节因子。数据库分析、CCK-8和qRT-PCR显示MiR-4723是胰腺癌中的一个癌基因。荧光素酶试验和qRT-PCR显示MiR-4723是Wnt7A/β-连环蛋白通路的负向调节因子。为了研究CAV2对MiR-4723/Wnt7A的作用机制，我们在MiR-4723过表达后通过qRT-PCR检测CAV2的基因表达。随后通过免疫荧光、蛋白质免疫印迹法和qRT-PCR分析了几个与内吞作用和上皮-间质转化（EMT）相关的基因。CAV2的过表达促进胰腺癌细胞的侵袭、迁移、克隆和转移。MiR-4723的过表达抑制CAV2的表达。在此，我们首次证明CAV2通过激活Wnt7A/β-连环蛋白信号通路对胰腺癌发挥促癌作用。CAV2可通过抑制内吞作用和促进EMT来调节胰腺癌细胞系中的MiR-4723/Wnt7A信号轴，从而实现其促癌作用机制。
