Department of Medicine, Division of Gastroenterology and Hepatology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
Department of Medicine, Division of Gastroenterology and Hepatology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
Biochim Biophys Acta Mol Cell Res. 2024 Oct;1871(7):119789. doi: 10.1016/j.bbamcr.2024.119789. Epub 2024 Jun 22.
The transcriptional regulator Krüppel-like factor 5 (KLF5) is highly expressed in squamous epithelial cells of the esophagus. Increased KLF5 activity induces tumorigenesis and promotes metastasis in several cancers, although this function appears to be context-dependent. Here, we demonstrate that acute KLF5 inhibition, both genetically and with the potent KLF5 inhibitor ML264, causes non-transformed human primary esophageal squamous epithelial cells to enter the epithelial to mesenchymal transition (EMT). Moreover, chronic KLF5 inhibition with ML264 leads to the development of cells with a mesenchymal phenotype characterized by the expression of mesenchymal markers and functionally by reduced cell growth and increased migration and cellular invasion. This EMT resulting from chronic KLF5 inhibition is not driven by β-Catenin or TGF-β signaling. Pharmacologically, ML264 inhibits KLF5 by promoting proteasomal-mediated degradation. Taken together, we demonstrate that reduced KLF5 activity reprograms epithelial cells towards a mesenchymal phenotype and enhances their migratory and invasive potential. These findings have potential implications not only for esophageal cancers but also for normal processes such as esophageal tissue repair following injury.
转录调节因子 Krüppel 样因子 5(KLF5)在食管的鳞状上皮细胞中高度表达。尽管这种功能似乎依赖于上下文,但增加的 KLF5 活性会诱导几种癌症的肿瘤发生和促进转移。在这里,我们证明急性 KLF5 抑制,无论是通过遗传还是使用强效 KLF5 抑制剂 ML264,都会导致非转化的人原发性食管鳞状上皮细胞进入上皮间质转化(EMT)。此外,用 ML264 进行慢性 KLF5 抑制会导致具有间充质表型的细胞发育,其特征是表达间充质标志物,并具有功能,例如细胞生长减少、迁移和细胞侵袭增加。这种由慢性 KLF5 抑制引起的 EMT 不是由 β-连环蛋白或 TGF-β 信号驱动的。药理学上,ML264 通过促进蛋白酶体介导的降解来抑制 KLF5。总之,我们证明降低 KLF5 活性会使上皮细胞向间充质表型重编程,并增强其迁移和侵袭潜力。这些发现不仅对食管癌有潜在影响,而且对正常过程(例如受伤后食管组织修复)也有潜在影响。