Based on a recent study of patients with immunoresistance to sorafenib and recurrence of HCC, and their anti-tumor response to ICIs (anti-PD-1) treatment, patients that presented no response to treatment, had in their microbiome overproduction of Proteobacteria, in comparison to those with the optimal response, which had an increased amount of Ruminococcus spp. Here, PDCD1 is linked to hepatocellular carcinoma.