ICOS and hepatocellular carcinoma: The frequencies of ICOS+ and CCR7+ CXCR5+CD45RA−CD4+ T cells were higher in HCC patients than in HC (P = 0.002 and P < 0.001, respectively, Figure 2B), and the percentage of ICOS+ Tfh cells was correlated with the incidence of cirrhosis in HCC patients (P = 0.039, Supplementary Table 2).