Sergent, PetraPinto-Cárdenas, Juan CarlosArreguin Carrillo, Adhara JacielLuna Dávalos, DanielGonzález Pérez, Marisa DanielaMendoza Lechuga, Dora AliciaAlonso Miguel, DanielSchaafsma, EvelienJiménez Cuarenta, AbigailCárdenas Muñoz, DianaZarabanda, YulianaPalisoul, Scott M.Lewis, Petra J.Kolling IV, Fred W.Affonso de Oliveira, Jessica FernandaSteinmetz, Nicole F.Rothstein, Jay L.Lines, LouiseNoelle, Randolph J.Fiering, StevenArias Pulido, Hugo2024-09-172024-09-172024-09-03Sergent, P., Pinto-Cárdenas, J. C., Carrillo, A. J. A., Dávalos, D. L., Pérez, M. D. G., Lechuga, D. A. M., Alonso-Miguel, D., Schaafsma, E., Cuarenta, A. J., Muñoz, D. C., Zarabanda, Y., Palisoul, S. M., Lewis, P. J., Kolling, F. W., 4th, Affonso de Oliveira, J. F., Steinmetz, N. F., Rothstein, J. L., Lines, L., Noelle, R. J., Fiering, S., … Arias-Pulido, H. (2024). An Abscopal Effect on Lung Metastases in Canine Mammary Cancer Patients Induced by Neoadjuvant Intratumoral Immunotherapy with Cowpea Mosaic Virus Nanoparticles and Anti-Canine PD-1. Cells, 13(17), 1478. https://doi.org/10.3390/cells1317147810.3390/cells13171478https://hdl.handle.net/20.500.14352/108215Neoadjuvant intratumoral (IT) therapy could amplify the weak responses to checkpoint blockade therapy observed in breast cancer (BC). In this study, we administered neoadjuvant IT anti-canine PD-1 therapy (IT acPD-1) alone or combined with IT cowpea mosaic virus therapy (IT CPMV/acPD-1) to companion dogs diagnosed with canine mammary cancer (CMC), a spontaneous tumor resembling human BC. CMC patients treated weekly with acPD-1 (n = 3) or CPMV/acPD-1 (n = 3) for four weeks or with CPMV/acPD-1 (n = 3 patients not candidates for surgery) for up to 11 weeks did not experience immune-related adverse events. We found that acPD-1 and CPMV/acPD-1 injections resulted in tumor control and a reduction in injected tumors in all patients and in noninjected tumors located in the ipsilateral and contralateral mammary chains of treated dogs. In two metastatic CMC patients, CPMV/acPD-1 treatments resulted in the control and reduction of established lung metastases. CPMV/acPD-1 treatments were associated with altered gene expression related to TLR1-4 signaling and complement pathways. These novel therapies could be effective for CMC patients. Owing to the extensive similarities between CMC and human BC, IT CPMV combined with approved anti-PD-1 therapies could be a novel and effective immunotherapy to treat local BC and suppress metastatic BC.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article2073-4409https://doi.org/10.3390/cells1317147839273048open access636.09:616-006.04Abscopal effectAnti-canine PD-1Canine NanoString arrayCanine mammary carcinomasCowpea mosaic virusImmune cellsIntratumoral injectionsLung metastasisPlant virusTumor microenvironmentVeterinaria3109 Ciencias Veterinarias