Multiple oncogenic and inflammatory pathways regulate PD-L1 expression in digestive system cancers including the EGFR/ERK signaling axis in esophageal squamous cell carcinoma (53), the JAK/STAT pathway in gastric cancer (54), and the ERK/MAPK pathway in hepatocellular carcinoma (55). Here, SOAT1 is linked to hepatocellular carcinoma.