EGLN1 and intrahepatic cholangiocarcinoma: The ICC of HK‐2 cells with knockdown of PHD2, which is believed to be the primary HIF prolyl hydroxylase in cell culture experiments (Strowitzki et al., 2019), produced similar results (Figure S6).These results indicated that the PHD‐VHL axis of HIF degradation was unrelated to HIF ring formation.