Michaela Feodoroff, Isabel Mogollón, Firas Hamdan, Tamara J. Luck, Romika Kumari, Paolo Bottega, Janita Sandberg, Erika Romppanen, Lassi Paavolainen, Minna Malmstedt, Patrick Penttilä, Olli Kallioniemi, Tuomas Mirtti, Antti Rannikko, Mikaela Grönholm, Vincenzo Cerullo, Vilja Pietiäinen
Introduction Clear cell renal cell carcinoma (ccRCC) remains a significant therapeutic challenge due to its biological heterogeneity, variable clinical behavior, and limited efficacy of single-agent systemic therapies. Combination strategies targeting multiple tumor-promoting pathways may improve therapeutic outcomes. Methods We evaluated combination treatment strategies integrating targeted systemic drugs with oncolytic adenovirus therapy using representative patient-derived cancer cell (PDC) models. Anti-tumor efficacy and immune-mediated cytotoxicity were assessed to investigate treatment responses across different patient-derived models. Results Combination treatment enhanced anti-tumor activity compared with either monotherapy alone and promoted immune-mediated cytotoxicity involving CD8+ T cells and natural killer (NK) cells. Treatment responses varied across the three PDC models, reflecting interpatient heterogeneity and suggesting potential value for biomarker-guided patient stratification. Discussion These findings demonstrate the potential of combining targeted therapy with oncolytic virotherapy to overcome current therapeutic limitations in ccRCC. Moreover, the use of advanced three-dimensional human-relevant PDC models provides a scalable platform for evaluating combination therapies, supporting personalized treatment strategies, and facilitating the development of therapeutic approaches applicable to ccRCC and other cancer types.