McCoy and coworkers [32] confirmed that Bifidobacterium pseudolongum and Lactobacillus johnsonii could significantly enhance the CD8+ T cell responses in the tumor microenvironment (TME) consistent with the improved efficacy of anti-PD-L1 and anti-CTLA-4 therapy on colorectal cancer. The gene discussed is CTLA4; the disease is neoplasm.