This study was performed to investigate the role of PTK7 in esophageal squamous cell carcinoma (ESCC) stem-like cells (CSCs). PTK7 expression in ESCCs identified by RT-qPCR, and CSC-like cells were isolated from populations of NEC and TE-1 cells. The CSC-like cells were verified by flow cytometric analyses performed using CD34 and CD133 antibodies, and RT-qPCR and western blot assays were used to examine the self-renewal capability of CSC-like cells. CSC-like cells treated with PTK7 siRNA or a P53-specific inhibitor (PFTα) were analyzed for their sphere formation capacity and their apoptosis and migration/invasion capabilities by sphere formation, flow cytometry, and transwell assay, respectively. Their levels of P53, MKK3, and cleaved caspase 3 expression were examined by western blot analysis. Our results revealed that a majority of the isolated CSC-like cells were CD34⁺/CD133⁺ double positive cells. Nango, Sox2, and OCT4 were dramatically increased in the separated CSC-like cells, which had the pluripotency and self-renewal properties of stem cells. Additional, PTK7 was dramatically upregulated in the ESCC tissues and CSC-like cells. An investigation of the function of CSC-like cells revealed that knockdown of PTK7 reduced their sphere formation, promoted apoptosis, and suppressed their migration and invasion abilities, all of which could be significantly reversed by PFTα. Mechanistic studies showed that PFTα could attenuate the upregulation of P53, MKK3, and cleaved caspase 3 expression that was induced by PTK7 knockdown in CSC-like cells. PTK7 increased the malignant behaviors of CSC-like cells derived from ESCC cells by regulating p53. Therefore, this study suggests PTK7 as an underlying target for therapy against ESCC.

中文翻译：

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PTK7 促进食管鳞状细胞系中癌症干细胞样细胞的恶性特性。

本研究旨在调查 PTK7 在食管鳞状细胞癌 (ESCC) 干细胞样细胞 (CSC) 中的作用。通过 RT-qPCR 鉴定的 ESCC 中的 PTK7 表达，以及从 NEC 和 TE-1 细胞群中分离出的 CSC 样细胞。通过使用 CD34 和 CD133 抗体进行的流式细胞术分析验证 CSC 样细胞，并使用 RT-qPCR 和蛋白质印迹测定来检查 CSC 样细胞的自我更新能力。分别通过球体形成、流式细胞术和 transwell 测定分析了用 PTK7 siRNA 或 P53 特异性抑制剂 (PFTα) 处理的 CSC 样细胞的球体形成能力及其凋亡和迁移/侵袭能力。通过蛋白质印迹分析检查它们的 P53、MKK3 和切割的 caspase 3 表达水平。⁺ /CD133 ⁺双阳性细胞。Nango、Sox2和OCT4在分离的CSC样细胞中显着增加，具有干细胞的多能性和自我更新特性。此外，PTK7 在 ESCC 组织和 CSC 样细胞中显着上调。对 CSC 样细胞功能的研究表明，PTK7 的敲低减少了它们的球体形成，促进了细胞凋亡，抑制了它们的迁移和侵袭能力，所有这些都可以被 PFTα 显着逆转。机制研究表明，PFTα 可以减弱 CSC 样细胞中 PTK7 敲低诱导的 P53、MKK3 和切割的半胱天冬酶 3 表达的上调。PTK7通过调节p53增加来源于ESCC细胞的CSC样细胞的恶性行为。所以，