ACS患者P2Y12受体拮抗剂抗血小板反应异质性的新机制:circFAM13B-miR126-PI3KR2信号轴的ceRNA调控

Dual antiplatelet therapy with P2Y12 inhibitor on top of aspirin is the cornerstone for the treatment of acute coronary syndrome (ACS), however, the heterogeneity of antiplatelet responsiveness increases the risk of serious ischemic and bleeding events. It has been confirmed that non-coding RNAs are enriched in platelet. Our previous study showed that the platelet circular RNA circFAM138 and miR126 as well as the target gene of PI3KR2 were associated with P2Y12 receptors antiplatelet responsiveness. Both circFAM13B and PI3KR2 share the microRNA response element of miR126. These findings indicated that the network regulation among circFAM13B, miR126, and PI3KR2 might contribute to the antiplatelet responsiveness of P2Y12 receptors. However, the mechanism remains unknown. In the project, we will confirm the association between platelet derived circFAM13B and miR126, and the antiplatelet responsiveness of the P2Y12 inhibitors in the patients with ACS. In the animal model, the influence of the circFAM13B and miR126 to the PI3KR2 expression and the antiplatelet responsiveness of the P2Y12 inhibitors will be investigated. Thereafter, we will approve that circFAM13B could function as a competing endogenous RNA to regulate PI3KR2 expression, and consequently the P2Y12 receptor antiplatelet responsiveness, by sponging miR126 in the differentiated human megakaryocyte model. The study will be warranted to provide the new target for the personalized antiplatelet therapy in patients with ACS.

P2Y12受体拮抗剂（P2Y12RI）是急性冠脉综合征（ACS）治疗的基石，但存在抗血小板反应异质性所致严重缺血/出血的风险。已知血小板富含非编码RNA，我们前期发现，血小板环状RNAcircFAM13B、miR126及靶基因PI3KR2分别与P2Y12RI反应性密切相关，且circFAM13B和PI3KR2均具备miR126应答原件，提示三者之间网络调控可能影响P2Y12RI反应性，但确切机制尚不清楚。鉴于此，本课题拟首先在ACS患者中，明确血小板circFAM13B及miR126与P2Y12RI反应性的关系；在动物模型中，分析circFAM13B和miR126的变化对PI3KR2表达和P2Y12RI反应性的影响；在细胞模型中，阐明circFAM13B和miR126通过竞争性内源RNA途径调控PI3KR2，进而影响P2Y12RI反应性的机制，以期为ACS患者个体化抗血小板治疗探索新靶点。

P2Y12受体拮抗剂是急性冠脉综合征（ACS）治疗的基石，但存在因抗血小板反应异质性所致严重缺血/出血的风险。本课题研究内容包括在ACS 患者的血小板中探索 miR126 及circFAM13B的表达与 P2Y12 受体拮抗剂抗血小板反应异质性相关性；在细胞模型中，对miR126 及circFAM13B通过调控血小板活化通路上的靶基因PI3KR2，进而影响 P2Y12 受体拮抗剂抗血小板反应性的机制进行了研究；并在动物模型中对P2Y12 受体拮抗剂抗血小板反应性以及血小板中 PI3KR2 靶基因和相关信号分子表达的影响进行了分析。本研究的重要结果包括，在ACS患者中发现血小板miR-126及circFAM13B的表达与P2Y12受体拮抗剂（氯吡格雷及替格瑞洛）的抗血小板反应异质性密切相关，且血小板miR-126功能性SNP（rs4636297）与P2Y12受体拮抗剂抗血小板治疗反应相关。在过表达或敲减miR-126-3p的MEG-01细胞系中，在证实miR-126-3p能够与PI3KR2靶向结合的基础上，发现血小板miR-126通过靶向负向调控PI3KR2的蛋白表达，进而促进P2Y12受体拮抗剂抗血小板活性；在证实circFAM13B可与miR-126靶向结合的基础上，发现血小板circFAM13B通过负向调控PI3KR2，进而促进P2Y12受体拮抗剂抗血小板活性。在动物实验中，成功构建了miR-126巨核细胞/血小板条件性敲除C57BL/6J小鼠模型，发现血小板miR-126能够对ADP诱导的血小板聚集功能及凝血酶诱导的血小板表面αIIbβIII结合纤维蛋白原能力产生负向调控作用，进而证实血小板miR-126能够正向调控P2Y12受体拮抗剂（替格瑞洛）抗血小板反应性；此外，血小板miR-126对三氯化铁诱导的颈动脉血栓形成能力具有负向调控作用。本课题聚焦环状RNA功能机制的前沿领域，通过独辟蹊径地探索血小板环状RNA在P2Y12受体拮抗剂抗血小板疗效异质性中的功能机制，证实了miR-126和circFAM13B可能通过协同靶向调控PI3KR2，进而促进P2Y12受体拮抗剂抗血小板药物的疗效，为ACS患者个体化抗栓治疗提供新的疗效监测标志物和新的治疗靶点，创新性地拓展了血小板环状RNA在抗栓精准用药领域的应用。