癌症干细胞（CSC）被认为是癌症发生、进展、化疗/放疗耐药、复发和转移的主要原因。间质液压力（IFP）增加是实体瘤的一个关键特征。我们之前的研究表明，肝癌干细胞（LCSC）的分布与肝癌组织内的机械异质性相关。然而，肝癌机械微环境对LCSC干性的调节作用尚不完全清楚。在这里，我们采用细胞压力加载装置来研究正常 IFP (5 mmHg) 以及增加的 IFP (40 和 200 mmHg) 对 LCSC 干性的影响。与对照 LCSC（暴露于 5 mmHg 压力负载）相比，暴露于 40 mmHg 压力负载的 LCSC 表现出 CSC 标志物（CD44、EpCAM、Nanog）表达显着上调、增强的球体和集落形成能力以及致瘤潜力，而持续将压力增加至 200mmHg 会抑制 LCSC 特性。从机制上讲，压力负荷调节 Yes 相关蛋白 (YAP) 活性和 Bcl-2 修饰因子 (BMF) 表达。 YAP 转录调节 BMF 表达以影响 LCSC 的干性。 YAP 的敲低和 BMF 的过表达减弱了压力介导的干性和致瘤性，而 YAP 缺陷和 BMF 缺失则消除了 LCSC 上压力依赖性干性，表明 YAP/BMF 信号轴参与了这一过程。总之，我们的研究结果为克服 CSC 的干性提供了一个潜在目标，并阐明了 IFP 增加在癌症进展中的重要性。© 2024 Wiley periodicals LLC。

Cancer stem cells (CSCs) are considered the major cause of the occurrence, progression, chemoresistance/radioresistance, recurrence, and metastasis of cancer. Increased interstitial fluid pressure (IFP) is a key feature of solid tumors. Our previous study showed that the distribution of liver cancer stem cells (LCSCs) correlated with the mechanical heterogeneity within liver cancer tissues. However, the regulation of liver cancer's mechanical microenvironment on the LCSC stemness is not fully understood. Here, we employed a cellular pressure-loading device to investigate the effects of normal IFP (5 mmHg), as well as increased IFP (40 and 200 mmHg) on the stemness of LCSCs. Compared to the control LCSCs (exposure to 5 mmHg pressure loading), the LCSCs exposed to 40 mmHg pressure loading exhibited significantly upregulated expression of CSC markers (CD44, EpCAM, Nanog), enhanced sphere and colony formation capacities, and tumorigenic potential, whereas continuously increased pressure to 200 mmHg suppressed the LCSC characteristics. Mechanistically, pressure loading regulated Yes-associated protein (YAP) activity and Bcl-2 modifying factor (BMF) expression. YAP transcriptionally regulated BMF expression to affect the stemness of LCSCs. Knockdown of YAP and overexpression of BMF attenuated pressure-mediated stemness and tumorgenicity, while YAP-deficient and BMF-deletion recused pressure-dependent stemness on LCSCs, suggesting the involvement of YAP/BMF signaling axis in this process. Together, our findings provide a potential target for overcoming the stemness of CSCs and elucidate the significance of increased IFP in cancer progression.© 2024 Wiley Periodicals LLC.