PMID- 33753566 OWN - NLM STAT- MEDLINE DCOM- 20211217 LR - 20240226 IS - 2051-1426 (Electronic) IS - 2051-1426 (Linking) VI - 9 IP - 3 DP - 2021 Mar TI - Regorafenib enhances antitumor immunity via inhibition of p38 kinase/Creb1/Klf4 axis in tumor-associated macrophages. LID - 10.1136/jitc-2020-001657 [doi] LID - e001657 AB - BACKGROUND: Regorafenib and other multikinase inhibitors may enhance antitumor efficacy of anti-program cell death-1 (anti-PD1) therapy in hepatocellular carcinoma (HCC). Its immunomodulatory effects, besides anti-angiogenesis, were not clearly defined. METHODS: In vivo antitumor efficacy was tested in multiple syngeneic liver cancer models. Murine bone marrow-derived macrophages (BMDMs) were tested in vitro for modulation of polarization by regorafenib and activation of cocultured T cells. Markers of M1/M2 polarization were measured by quantitative reverse transcription PCR (RT-PCR), arginase activity, flow cytometry, and ELISA. Knockdown of p38 kinase and downstream Creb1/Klf4 signaling on macrophage polarization were confirmed by using knockdown of the upstream MAPK14 kinase, chemical p38 kinase inhibitor, and chromatin immunoprecipitation. RESULTS: Regorafenib (5 mg/kg/day, corresponding to about half of human clinical dosage) inhibited tumor growth and angiogenesis in vivo similarly to DC-101 (anti-VEGFR2 antibody) but produced higher T cell activation and M1 macrophage polarization, increased the ratio of M1/M2 polarized BMDMs and proliferation/activation of cocultured T cells in vitro, indicating angiogenesis-independent immunomodulatory effects. Suppression of p38 kinase phosphorylation and downstream Creb1/Klf4 activity in BMDMs by regorafenib reversed M2 polarization. Regorafenib enhanced antitumor efficacy of adoptively transferred antigen-specific T cells. Synergistic antitumor efficacy between regorafenib and anti-PD1 was associated with multiple immune-related pathways in the tumor microenvironment. CONCLUSION: Regorafenib may enhance antitumor immunity through modulation of macrophage polarization, independent of its anti-angiogenic effects. Optimization of regorafenib dosage for rational design of combination therapy regimen may improve the therapeutic index in the clinic. CI - (c) Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ. FAU - Ou, Da-Liang AU - Ou DL AUID- ORCID: 0000-0002-8368-1141 AD - Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan. FAU - Chen, Chia-Wei AU - Chen CW AD - Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan. FAU - Hsu, Chia-Lang AU - Hsu CL AD - Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan. AD - Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan. AD - Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan. FAU - Chung, Chih-Hung AU - Chung CH AD - Taiwan International Graduate Program in Molecular Medicine, National Yang-Ming University, Taipei, Taiwan. FAU - Feng, Zi-Rui AU - Feng ZR AD - Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan. FAU - Lee, Bin-Shyun AU - Lee BS AD - Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan. FAU - Cheng, Ann-Lii AU - Cheng AL AD - Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan. AD - National Taiwan University Cancer Center, Taipei, Taiwan. AD - Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan. FAU - Yang, Muh-Hwa AU - Yang MH AUID- ORCID: 0000-0002-8918-1244 AD - Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan chsu1967@ntu.edu.tw mhyang2@vghtpe.gov.tw. AD - Division of Medical Oncology, Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan. FAU - Hsu, Chiun AU - Hsu C AUID- ORCID: 0000-0002-1122-0055 AD - Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan chsu1967@ntu.edu.tw mhyang2@vghtpe.gov.tw. AD - Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan. AD - National Taiwan University Cancer Center, Taipei, Taiwan. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't PL - England TA - J Immunother Cancer JT - Journal for immunotherapy of cancer JID - 101620585 RN - 0 (Angiogenesis Inhibitors) RN - 0 (Antineoplastic Agents) RN - 0 (Creb1 protein, mouse) RN - 0 (Cyclic AMP Response Element-Binding Protein) RN - 0 (Klf4 protein, mouse) RN - 0 (Kruppel-Like Factor 4) RN - 0 (Phenylurea Compounds) RN - 0 (Protein Kinase Inhibitors) RN - 0 (Pyridines) RN - 24T2A1DOYB (regorafenib) RN - EC 2.7.11.24 (p38 Mitogen-Activated Protein Kinases) SB - IM MH - Angiogenesis Inhibitors/pharmacology MH - Animals MH - Antineoplastic Agents/*pharmacology MH - Carcinoma, Hepatocellular/*drug therapy/enzymology/immunology MH - Cell Line, Tumor MH - Coculture Techniques MH - Cyclic AMP Response Element-Binding Protein/*metabolism MH - Kruppel-Like Factor 4/metabolism MH - Liver Neoplasms/*drug therapy/enzymology/immunology MH - Lymphocyte Activation/drug effects MH - Lymphocytes, Tumor-Infiltrating/drug effects/enzymology/immunology MH - Mice, Inbred BALB C MH - Mice, Inbred C57BL MH - Mice, Transgenic MH - Phenotype MH - Phenylurea Compounds/*pharmacology MH - Protein Kinase Inhibitors/*pharmacology MH - Pyridines/*pharmacology MH - Signal Transduction MH - Tumor Microenvironment MH - Tumor-Associated Macrophages/*drug effects/enzymology/immunology MH - p38 Mitogen-Activated Protein Kinases/*metabolism MH - Mice PMC - PMC7986673 OTO - NOTNLM OT - immunomodulation OT - immunotherapy OT - tumor microenvironment COIS- Competing interests: Dr A-L Cheng is a consultant for and a member of the speaker's bureau of Bayer-Schering Pharma. Dr A-L Cheng is a consultant of Novartis, Merck Serono, Eisai, Merck Sharp & Dohme (MSD) Corp., ONXEO, Bayer HealthCare Pharmaceuticals Inc., Bristol-Myers Squibb (BMS) Company, and Ono Pharmaceutical Co., Ltd. Dr C Hsu received research grants from BMS/ONO, Roche, and Ipsen and received honorarium from the following pharmaceutical companies: AstraZeneca, Bayer, BMS/ONO, Eisai, Eli Lilly, Ipsen, Merck Serono, MSD, Novartis, Roche, and TTY Biopharm. EDAT- 2021/03/24 06:00 MHDA- 2021/12/18 06:00 PMCR- 2021/03/22 CRDT- 2021/03/23 06:23 PHST- 2020/12/15 00:00 [accepted] PHST- 2021/03/23 06:23 [entrez] PHST- 2021/03/24 06:00 [pubmed] PHST- 2021/12/18 06:00 [medline] PHST- 2021/03/22 00:00 [pmc-release] AID - jitc-2020-001657 [pii] AID - 10.1136/jitc-2020-001657 [doi] PST - ppublish SO - J Immunother Cancer. 2021 Mar;9(3):e001657. doi: 10.1136/jitc-2020-001657.