Targeting TLR2/Rac1/cdc42/JNK Pathway to Reveal That Ruxolitinib Promotes Thrombocytopoiesis

• Published in: International journal of molecular sciences Vol. 23; no. 24; p. 16137
• Main Authors: Yang, Shuo, Tang, Xiaoqin, Wang, Long, Ni, Chengyang, Wu, Yuesong, Zhou, Ling, Zeng, Yueying, Zhao, Chunling, Wu, Anguo, Wang, Qiaozhi, Xu, Xiyan, Wang, Yiwei, Chen, Rong, Zhang, Xiao, Zou, Lile, Huang, Xinwu, Wu, Jianming
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 17.12.2022; MDPI
• Subjects: Animals; Antigens; Blood diseases; Blood platelets; Bone marrow; cdc42 GTP-Binding Protein - metabolism; Cdc42 protein; Cell growth; Chemotherapy; Cytoskeleton; Differentiation; Drug dosages; Flow cytometry; Immunofluorescence; Kinases; MAP Kinase Signaling System; Maturation; Megakaryocytes; Mice; Molecular docking; Molecular Docking Simulation; Phalloidin; Pharmacology; rac1 GTP-Binding Protein - metabolism; Rac1 protein; Radiation; Radiation therapy; rusolitinib; Stability analysis; Targeted cancer therapy; Thrombocytopenia; thrombocytopoiesis; Thrombopoiesis; TLR2 protein; TLR2/Rac1/cdc42/JNK; Toll-Like Receptor 2 - metabolism; Toll-like receptors; Transcription factors; thrombocytopoiesis; rusolitinib; radiation; MK; TLR2/Rac1/cdc42/JNK
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms232416137

Thrombocytopenia has long been considered an important complication of chemotherapy and radiotherapy, which severely limits the effectiveness of cancer treatment and the overall survival of patients. However, clinical treatment options are extremely limited so far. Ruxolitinib is a potential candidate. The impact of ruxolitinib on the differentiation and maturation of K562 and Meg-01 cells megakaryocytes (MKs) was examined by flow cytometry, Giemsa and Phalloidin staining. A mouse model of radiation-injured thrombocytopenia (RIT) was employed to evaluate the action of ruxolitinib on thrombocytopoiesis. Network pharmacology, molecular docking, drug affinity responsive target stability assay (DARTS), RNA sequencing, protein blotting and immunofluorescence analysis were applied to explore the targets and mechanisms of action of ruxolitinib. Ruxolitinib can stimulate MK differentiation and maturation in a dose-dependent manner and accelerates recovery of MKs and thrombocytopoiesis in RIT mice. Biological targeting analysis showed that ruxolitinib binds directly to Toll Like Receptor 2 (TLR2) to activate Rac1/cdc42/JNK, and this action was shown to be blocked by C29, a specific inhibitor of TLR2. Ruxolitinib was first identified to facilitate MK differentiation and thrombocytopoiesis, which may alleviate RIT. The potential mechanism of ruxolitinib was to promote MK differentiation via activating the Rac1/cdc42/JNK pathway through binding to TLR2.