PT - JOURNAL ARTICLE AU - Xiao, Ruipei AU - Zhao, Wenli AU - Lin, Wei AU - Xiao, Yudian AU - Ren, Jie AU - Zhou, Yang AU - Meng, Wei AU - Bi, Enguang AU - Jiang, Ling TI - Bendamustine–rituximab elicits dual tumoricidal and immunomodulatory responses via cGAS–STING activation in diffuse large B-cell lymphoma AID - 10.1136/jitc-2024-009212 DP - 2024 Nov 01 TA - Journal for ImmunoTherapy of Cancer PG - e009212 VI - 12 IP - 11 4099 - http://jitc.bmj.com/content/12/11/e009212.short 4100 - http://jitc.bmj.com/content/12/11/e009212.full SO - J Immunother Cancer2024 Nov 01; 12 AB - Background Bendamustine–rituximab (BR) therapy stands out as a promising alternative for elderly patients with diffuse large B-cell lymphoma (DLBCL), demonstrating notable efficacy when conventional regimens pose challenges. Despite its clinical success, the intricate mechanisms underlying BR therapy have remained elusive.Methods DLBCL cell lines were used to investigate the mechanism of BR therapy in vitro. RNA-seq and Western blot were used to explore the target pathways of BR therapy. STING was knocked out using Crispr-cas9 and inhibited using H-151 to investigate its role in BR therapy. Bulk RNA-seq and single-cell RNA-seq data from patients were analyzed to investigate the association between STING and pyroptosis pathways, validated using STING downregulated cells. Flow cytometry, transwell experiments and co-culture experiments were performed to investigate the inflammatory phenotype of DLBCL cells after BR treatment and its effect on T-cell recruitment and activation.Results This study elucidates that BR elicits direct tumoricidal effects by promoting apoptosis and inducing cell cycle arrest. The synergistic impact with rituximab is further potentiated by complement addition, demonstrating the pivotal role of in vivo antibody-dependent cellular cytotoxicity. Moreover, our investigation reveals that, through a cGAS–STING-dependent pathway, prolonged exposure to BR induces pyroptosis in DLBCL cells. Activation of the cGAS–STING pathway by BR therapy triggers the release of inflammatory factors and upregulates major histocompatibility complex molecules, shaping an immunologically hot tumor microenvironment.Conclusions This unique dual influence not only directly targets DLBCL cells but also engages the patient’s immune system, paving the way for innovative combination therapies. The study provides comprehensive insights into the multifaceted actions of BR in DLBCL, offering a foundation for refined and personalized treatment strategies in elderly patients.Data are available in a public, open access repository. Data are available upon reasonable request. Four scRNA-seq samples from preview study were obtained from GEO (https://www.nicbi.nlm.nih.gov/geo/) under accession code GSE182434. Three scRNA-seq samples from preview study were obtained from heiDATA (https://heidata.uni-heidelberg.de/) under accession code VRJUNV. DLBCL GDC data (project NCICCR-DLBCL and CTSP-DLBCL1) were download from https://api.gdc.cancer.gov/data/894155a9-b039-4d50-966c-997b0e2efbc2. Sample clinical data were download from https://api.gdc.cancer.gov/data/529be438-e42c-4725-a3f3-66f6fd42ffae. RNA-seq data of this study are available in GEO (https://www.nicbi.nlm.nih.gov/geo/) under accession code GSE249466. All data used in this study are publicly available for download. All data are available on request from the authors.