Here, histopathological analysis of colons confirmed that L. paracasei sh2020 administration might help to maintain intestinal homeostasis by modulating gut microbiota, which was a novel and promising strategy to mitigate the immune checkpoint inhibitor-associated colitis.32 In all, L. paracasei sh2020 could ameliorate gut microbiota changes induced by anti-PD-1 therapy, and thus restore the homeostasis of gut microecology. This evidence concerns the gene PDCD1 and colitis.