Data from Radiotherapy and Cisplatin Increase Immunotherapy Efficacy by Enabling Local and Systemic Intratumoral T-cell Activity

• DOI: 10.1158/2326-6066.c.6550047.v1
• Publication Date: 2023-04-04T19:43:02Z
• Authors: Paula Kroon; Elselien Frijlink; Victoria Iglesias...; Andriy Volkov; Marit M. van Buuren; Ton N. Schumacher; Marcel Verheij; Jannie Borst; Inge Verbrugge
• Keywords: CTL*; CD137

<div>Abstract<p>To increase cancer immunotherapy success, PD-1 blockade must be combined with rationally selected treatments. Here, we examined, in a poorly immunogenic mouse breast model, the potential of antibody-based immunomodulation and conventional anticancer treatments to collaborate anti–PD-1 treatment. One requirement improve anti-PD-1–mediated tumor control was promote tumor-specific cytotoxic T-cell (CTL) priming, which achieved by stimulating CD137 costimulatory receptor. A second overrule PD-1–unrelated mechanisms CTL suppression microenvironment (TME). This radiotherapy cisplatin In context CD137/PD-1–targeting immunotherapy, allowed for elimination altering TME, rather than intrinsic functionality. Combining this radioimmunotherapy regimen low-dose improved CTL-dependent regression contralateral outside radiation field. Thus, systemic may combining protocols that priming (chemo)radiation permit activity both irradiated (occult) metastases.</p></div>