Anagh A. Sahasrabuddhe, Xiaofei Chen, Kaiyu Ma, Rui Wu, Huan-Chang Liang, Richa Kapoor, Rishi R. Chhipa, Ozlem Onder, Courtney McFetridge, John S. Van Arnam, Xiao Zhang, Jennifer J.D. Morrissette, Vinodh Pillai, Marilyn M. Li, Philippe Szankasi, Venkatesha Basrur, Kevin P. Conlon, Tobias D. Raabe, Nathanael G. Bailey, Cory M. Hogaboam, Robert Rottapel, Junhyong Kim, Cristina López, Matthias Schlesner, Reiner Siebert, Kostiantyn Dreval, Ryan D. Morin, Loredana Moro, Michele Pagano, Louis M. Staudt, Megan S. Lim, Kojo S.J. Elenitoba-Johnson
{"title":"The FBXO45-GEF-H1 axis controls germinal center formation and B-cell lymphomagenesis","authors":"Anagh A. Sahasrabuddhe, Xiaofei Chen, Kaiyu Ma, Rui Wu, Huan-Chang Liang, Richa Kapoor, Rishi R. Chhipa, Ozlem Onder, Courtney McFetridge, John S. Van Arnam, Xiao Zhang, Jennifer J.D. Morrissette, Vinodh Pillai, Marilyn M. Li, Philippe Szankasi, Venkatesha Basrur, Kevin P. Conlon, Tobias D. Raabe, Nathanael G. Bailey, Cory M. Hogaboam, Robert Rottapel, Junhyong Kim, Cristina López, Matthias Schlesner, Reiner Siebert, Kostiantyn Dreval, Ryan D. Morin, Loredana Moro, Michele Pagano, Louis M. Staudt, Megan S. Lim, Kojo S.J. Elenitoba-Johnson","doi":"10.1158/2159-8290.cd-24-0442","DOIUrl":null,"url":null,"abstract":"The role of ubiquitin-mediated degradation mechanisms in the pathogenesis of diffuse large B cell (DLBCL) and follicular lymphoma (FL) is not completely understood. We show that conditional deletion of the E3 ubiquitin ligase Fbxo45 in germinal center B-cells results in B-cell lymphomagenesis in homozygous (100%) and heterozygous (48%) mice. Mechanistically, FBXO45 targets the RHO guanine exchange factor ARHGEF2/GEF-H1 for ubiquitin-mediated degradation. Double genetic ablation of Fbxo45 and Arhgef2 ameliorated lymphoma formation. Transgenic knock-in mice harboring a GEF-H1 mutant unable to bind FBXO45 develop B-cell lymphomas with ~50% penetrance. Genome sequencing in human lymphomas identified mutually-exclusive FBXO45 copy number losses and ARHGEF2 gains, with combined frequencies ranging from 26.32% in FL to 45.12% in DLBCL. Notably, FBXO45 silencing enhances sensitivity to MEK1/2 inhibition. These results identify FBXO45 and ARHGEF2 as a novel tumor-suppressor and oncogene pair involved in the pathogenesis of B-cell lymphomas with significant implications for targeted therapies.","PeriodicalId":9430,"journal":{"name":"Cancer discovery","volume":"30 1","pages":""},"PeriodicalIF":29.7000,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cancer discovery","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1158/2159-8290.cd-24-0442","RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ONCOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The role of ubiquitin-mediated degradation mechanisms in the pathogenesis of diffuse large B cell (DLBCL) and follicular lymphoma (FL) is not completely understood. We show that conditional deletion of the E3 ubiquitin ligase Fbxo45 in germinal center B-cells results in B-cell lymphomagenesis in homozygous (100%) and heterozygous (48%) mice. Mechanistically, FBXO45 targets the RHO guanine exchange factor ARHGEF2/GEF-H1 for ubiquitin-mediated degradation. Double genetic ablation of Fbxo45 and Arhgef2 ameliorated lymphoma formation. Transgenic knock-in mice harboring a GEF-H1 mutant unable to bind FBXO45 develop B-cell lymphomas with ~50% penetrance. Genome sequencing in human lymphomas identified mutually-exclusive FBXO45 copy number losses and ARHGEF2 gains, with combined frequencies ranging from 26.32% in FL to 45.12% in DLBCL. Notably, FBXO45 silencing enhances sensitivity to MEK1/2 inhibition. These results identify FBXO45 and ARHGEF2 as a novel tumor-suppressor and oncogene pair involved in the pathogenesis of B-cell lymphomas with significant implications for targeted therapies.
期刊介绍:
Cancer Discovery publishes high-impact, peer-reviewed articles detailing significant advances in both research and clinical trials. Serving as a premier cancer information resource, the journal also features Review Articles, Perspectives, Commentaries, News stories, and Research Watch summaries to keep readers abreast of the latest findings in the field. Covering a wide range of topics, from laboratory research to clinical trials and epidemiologic studies, Cancer Discovery spans the entire spectrum of cancer research and medicine.