CCL22 and hepatocellular carcinoma: Among 90 patients with HCC, high HIF‐1α expression strongly correlated with the presence of PVTT and poor prognosis, concomitant with elevated CCL22 expression, indicating that hypoxia/HIF‐1α/CCL20/IDO axis in HCC was important for promoting metastasis through inducing EMT and establishing an immunosuppressive microenvironment.