腹膜转移是导致胃癌预后不良的最常见危险因素之一。我们之前报道过胃癌细胞的细胞外囊泡可以促进腹膜转移。然而，它们对缺氧条件下胃癌诱导的腹膜转移的影响仍不清楚。本研究旨在阐明耐缺氧胃癌细胞来源的细胞外囊泡如何影响常氧胃癌细胞的腹膜转移。蛋白质组学分析显示，耐缺氧胃癌细胞及其相应的细胞外囊泡中 Caveolin1 和层粘连蛋白 β2 的水平升高。重要的是，Caveolin1被发现在介导Laminin β2分选至耐缺氧胃癌细胞的细胞外囊泡中发挥核心作用，随后，细胞外囊泡相关的Laminin β2通过激活AKT途径促进常氧胃癌细胞的腹膜转移。进一步研究证实，Rho 相关卷曲螺旋激酶 1 介导的 Y14 残基磷酸化对 Caveolin1 的激活是促进层粘连蛋白 β2 分选至细胞外囊泡的关键因素。此外，Y14 磷酸化的 Caveolin1 通过激活 Rab11 增强了层粘连蛋白 β2 的分选。最后，我们的研究表明，对血浆细胞外囊泡相关的 Caveolin1 和细胞外囊泡相关的层粘连蛋白 β2 进行综合评估可以为胃癌腹膜转移的发生提供准确的预测工具。© 2024。作者，独家许可施普林格自然有限公司。

Peritoneal metastasis is one of the most common risk factors contributing to the poor prognosis of gastric cancer. We previously reported that extracellular vesicles from gastric cancer cells could facilitate peritoneal metastasis. However, their impact on gastric cancer-induced peritoneal metastasis under hypoxic conditions remains unclear. This study aims to elucidate how hypoxia-resistant gastric cancer cell-derived extracellular vesicles affect the peritoneal metastasis of normoxic gastric cancer cells. Proteomic analysis revealed elevated levels of Caveolin1 and Laminin β2 in hypoxia-resistant gastric cancer cells and their corresponding extracellular vesicles. Importantly, Caveolin1 was found to play a central role in mediating Laminin β2 sorting into extracellular vesicles derived from hypoxia-resistant gastric cancer cells, and subsequently, extracellular vesicle-associated Laminin β2 promoted peritoneal metastasis in normoxic gastric cancer cells by activating the AKT pathway. Further investigation confirmed that Caveolin1 activation by Rho-related Coiled-coil kinase 1-mediated phosphorylation of Y14 residue is a key factor facilitating Laminin β2 sorting into extracellular vesicles. Moreover, Y14 phosphorylated- Caveolin1 enhanced Laminin β2 sorting by activating Rab11. Finally, our study demonstrated that a combined assessment of plasma extracellular vesicle-associated Caveolin1 and extracellular vesicle-associated Laminin β2 could provide an accurate predictive tool for peritoneal metastasis occurrence in gastric cancer.© 2024. The Author(s), under exclusive licence to Springer Nature Limited.