Zhang Pei, Liu Mingkai, Zhang Shun, Lu Cuijuan, Zu Qianhe, Liang Yuemian, Cui Zhenyu, Liu Jialin, Wang Yanan, Bu Chunyan
Department of Pathology, Affiliated Hospital of Hebei University, No 212, Yuhua East Road, Baoding, Hebei, 071000, China.
Department of Urology, Affiliated Hospital of Hebei University, Baoding, Hebei, 071000, China.
BMC Urol. 2025 Apr 7;25(1):77. doi: 10.1186/s12894-025-01760-4.
Bladder cancer is a common malignant tumor of the urinary tract as well as one of the most common cancers worldwide. Therefore, the study of key molecular targets involved in bladder carcinogenesis and progression is crucial for the prognosis of bladder cancer. Our study aims to investigate the mechanism by which cytokeratin 17 induces epithelial-mesenchymal transition and promotes bladder cancer progression.
In this study, 78 bladder cancer tissue specimens were collected, the expression level of cytokeratin 17 (CK17) in bladder cancer and paracancerous tissues was detected by immunohistochemistry, and the relationship between the CK17 expression level and the prognosis of the patients was analyzed via follow-up visits. Western Blot was performed to detect the expression level of CK17 in common bladder cancer cell lines, and the CK17-silenced and overexpressed cell lines were constructed from the selected T24 cell line with high expression of CK17 and 5637 cell line with low expression of CK17. The effects of CK17 on the proliferation, migration and invasion abilities of bladder cancer cells were evaluated by flow cytometry, Cell Counting Kit-8 (CCK-8) assay, Trans-well assay, and scratch assay. The effect of CK17 on epithelial-mesenchymal transition (EMT) markers was further detected by Western Blot and immunofluorescence, and the phosphorylation levels of AKT Ser473 and Thr308 were detected by Western Blot.
In the clinical samples, CK17 expression was significantly up-regulated in cancer tissues compared with paracancerous tissues, and high levels of CK17 indicated shortened progression free survival and predicted a poorer clinical prognosis. By analyzing the relationship between CK17 and clinicopathological features, we found that the CK17 expression level was correlated with bladder cancer grade and TNM stage. Overexpression of CK17 promoted the proliferation, migration and invasion abilities of bladder cancer cells 5637, and silencing of CK17 inhibited the proliferation, migration and invasion abilities of bladder cancer cells T24. Further, we found that overexpression of CK17 in 5637 cells activated the AKT signaling pathway by increasing the phosphorylation level of AKT (Ser473), so as to up-regulate the expressions of the EMT mesenchymal markers vimentin, N-cadherin, and the transcription factors Slug and twist, while the opposite results were obtained by silencing CK17 in T24 cells.
We found that high expression of CK17 promoted the proliferation, migration and invasion of bladder cancer cells and induced EMT through AKT-Ser473 phosphorylation. These findings suggest that CK17 is significantly associated with malignant progression and poor prognosis of bladder cancer patients, and it may become a new biological target for bladder cancer treatment.
膀胱癌是泌尿系统常见的恶性肿瘤，也是全球最常见的癌症之一。因此，研究参与膀胱癌发生和进展的关键分子靶点对于膀胱癌的预后至关重要。本研究旨在探讨细胞角蛋白17诱导上皮-间质转化并促进膀胱癌进展的机制。
本研究收集了78例膀胱癌组织标本，采用免疫组织化学法检测膀胱癌组织和癌旁组织中细胞角蛋白17（CK17）的表达水平，并通过随访分析CK17表达水平与患者预后的关系。采用蛋白质免疫印迹法检测常见膀胱癌细胞系中CK17的表达水平，并从CK17高表达的T24细胞系和CK17低表达的5637细胞系中构建CK17沉默和过表达细胞系。通过流式细胞术、细胞计数试剂盒-8（CCK-8）法、Trans-well法和划痕试验评估CK17对膀胱癌细胞增殖、迁移和侵袭能力的影响。通过蛋白质免疫印迹法和免疫荧光进一步检测CK17对上皮-间质转化（EMT）标志物的影响，并通过蛋白质免疫印迹法检测AKT Ser473和Thr308的磷酸化水平。
在临床样本中，与癌旁组织相比，癌组织中CK17表达显著上调，高水平的CK17表明无进展生存期缩短，并预示临床预后较差。通过分析CK17与临床病理特征的关系，我们发现CK17表达水平与膀胱癌分级和TNM分期相关。CK17过表达促进了膀胱癌细胞5637的增殖、迁移和侵袭能力，而CK17沉默则抑制了膀胱癌细胞T24的增殖、迁移和侵袭能力。此外，我们发现5637细胞中CK17过表达通过增加AKT（Ser473）的磷酸化水平激活了AKT信号通路，从而上调EMT间质标志物波形蛋白、N-钙黏蛋白以及转录因子Slug和twist的表达，而在T24细胞中沉默CK17则得到相反的结果。
我们发现CK17高表达促进膀胱癌细胞的增殖、迁移和侵袭，并通过AKT-Ser473磷酸化诱导EMT。这些发现表明CK17与膀胱癌患者的恶性进展和不良预后显著相关，它可能成为膀胱癌治疗的新生物靶点。
