HIF1A and hepatocellular carcinoma: The average HIF-1α or CA IX density was largest for combinational group I and smallest for group IV in HCC Cohort 1 and PC Cohort 2 (one-way analysis of variance, p<0.001 and p = 0.008 for HIF-1α, and p = 0.012 and p<0.001 for CA IX, respectively; Fig. 5).