Indeed, pilot clinical studies assessing the effectiveness of therapeutic antibodies against canine PD-L1 and PD-1 for advanced spontaneous cancers in dogs have shown some success in canine oral melanoma and undifferentiated sarcoma patients (Maekawa et al., 2017; Igase et al., 2020). The gene discussed is CD274; the disease is undifferentiated (embryonal) sarcoma.