This effect could have been linked with enhanced OXPHOS and mitogenic ROS production from mitochondria as supported by similar studies in which treatment with PPAR activator bezafibrate combined with PD-1 blockade but not alone, led to CD8+ T cell activation through mitochondrial expansion correlating with decreased tumor growth and increased survival of MC38 tumor-bearing mice [105,113]. The gene discussed is CD8A; the disease is neoplasm.