血小板细胞外囊泡（PEV）在肿瘤发展中发挥着重要作用。然而，其生物发生的机制尚未完全阐明。蛋白激酶Cα（PKCα）是血小板活化的重要调节因子，但PKCα对EV生成的影响尚不清楚。我们使用小颗粒流式细胞术发现，与良性乳腺疾病患者相比，乳腺癌患者的 PEV 数量有所增加。与此同时，乳腺癌血小板中活化的 PKCα 水平也随之增加。用 PKCα 激动剂佛波醇 12-肉豆蔻酸酯 13-乙酸酯 (PMA) 处理血小板可增加 PKCα 磷酸化并诱导 PEV 产生，而 PKCα 抑制剂 GÖ6976 则显示出相反的效果。值得注意的是，将良性肿瘤患者的血小板与 MDA-MB-231 细胞的培养上清液一起孵育可诱导血小板中的 PKCα 磷酸化。质谱和免疫共沉淀分析表明，三磷酸鸟苷结合蛋白家族的成员 Dynamin 2 (DNM2) 可能与激活的 PKCα 协同调节乳腺癌血小板产生 PEV。在小鼠肺转移模型中观察到类似的结果。此外，PEV 被乳腺癌细胞吞噬，并通过 miR-1297 传递促进癌细胞迁移和侵袭。这些发现表明，PKCα 与 DNM2 协同诱导 PEV 产生，而 PEV 释放可能由乳腺癌环境中的因素触发。© 作者。

Platelet extracellular vesicles (PEVs) play an important role in tumor development. However, the mechanisms underlying their biogenesis have not been fully elucidated. Protein kinase Cα (PKCα) is an important regulator of platelet activation, but the effect of PKCα on EV generation is unclear. We used small-particle flow cytometry and found that the number of PEVs was increased in patients with breast cancer compared to those with benign breast disease. This was accompanied by increased levels of activated PKCα in breast cancer platelets. Treating platelets with the PKCα agonist phorbol 12-myristate 13-acetate (PMA) increased the phosphorylation PKCα and induced PEV production, while the PKCα inhibitor GÖ6976 showed the opposite effects. Notably, incubating platelets from patients with benign tumors with the culture supernatant of MDA-MB-231 cells induced PKCα phosphorylation in the platelets. Mass spectrometry and coimmunoprecipitation assays showed that Dynamin 2 (DNM2), a member of the guanosine-triphosphate-binding protein family, might cooperate with activated PKCα to regulate PEV production by breast cancer platelets. Similar results were observed in a mouse model of lung metastasis. In addition, PEVs were engulfed by breast cancer cells and promoted cancer cell migration and invasion via miR-1297 delivery. These findings suggested that PKCα cooperates with DNM2 to induce PEV generation, and PEV release might triggered by factors in the breast cancer environment.© The author(s).