肿瘤微环境（TME）中普遍存在的溶血磷脂酸（LPA）会对多种癌症产生不利影响。在卵巢癌中，18:0 和 20:4 LPA 种类选择性地与较短的无复发生存期相关，表明对细胞信号网络有明显的影响。巨噬细胞代表了 TME 中高度相关的细胞类型，但 LPA 对这些细胞的影响仍然不清楚。在这里，我们通过无偏磷酸蛋白质组学发现了人类单核细胞来源的巨噬细胞中不同的 LPA 物种特异性反应，其中 87 个和 161 个磷酸位点分别被 20:4 和 18:0 LPA 上调，并且只有 24 个共享位点。下调磷酸位点的特异性更为明显（163 个位点对 5 个位点）。考虑到 TME 中高水平的 20:4 LPA 及其与不良生存率的选择性关联，这一发现可能具有重要意义。通路分析确定 RHO/RAC1 GTPase 信号传导是主要受影响的靶点，包括 AHRGEF 和 DOCK 鸟嘌呤交换因子、ARHGAP GTPase 激活蛋白和调节蛋白激酶。与这些发现一致的是，暴露于 20:4 导致肌动蛋白丝网络发生强烈改变，从而增强巨噬细胞迁移。此外，20:4 LPA 诱导 p38 磷酸化，这是 18:0 LPA 未反映的反应，而 AKT 的模式则相反。此外，RNA 分析确定了参与胆固醇/脂质代谢的基因作为 20:4 LPA 的选择性靶标。这些发现表明，两种 LPA 物种协同调节不同的途径，以支持 TME 内促肿瘤巨噬细胞所必需的功能。其中包括通过 AKT 激活实现细胞存活以及通过 RHO/RAC1 和 p38 信号传导实现细胞迁移。

Lysophosphatidic acid (LPA) species, prevalent in the tumor microenvironment (TME), adversely impact various cancers. In ovarian cancer, the 18:0 and 20:4 LPA species are selectively associated with shorter relapse-free survival, indicating distinct effects on cellular signaling networks. Macrophages represent a cell type of high relevance in the TME, but the impact of LPA on these cells remains obscure. Here, we uncovered distinct LPA-species-specific responses in human monocyte-derived macrophages through unbiased phosphoproteomics, with 87 and 161 phosphosites upregulated by 20:4 and 18:0 LPA, respectively, and only 24 shared sites. Specificity was even more pronounced for downregulated phosphosites (163 versus 5 sites). Considering the high levels 20:4 LPA in the TME and its selective association with poor survival, this finding may hold significant implications. Pathway analysis pinpointed RHO/RAC1 GTPase signaling as the predominantly impacted target, including AHRGEF and DOCK guanine exchange factors, ARHGAP GTPase activating proteins, and regulatory protein kinases. Consistent with these findings, exposure to 20:4 resulted in strong alterations to the actin filament network and a consequent enhancement of macrophage migration. Moreover, 20:4 LPA induced p38 phosphorylation, a response not mirrored by 18:0 LPA, whereas the pattern for AKT was reversed. Furthermore, RNA profiling identified genes involved in cholesterol/lipid metabolism as selective targets of 20:4 LPA. These findings imply that the two LPA species cooperatively regulate different pathways to support functions essential for pro-tumorigenic macrophages within the TME. These include cellular survival via AKT activation and migration through RHO/RAC1 and p38 signaling.