The expression of PD-L1 in different cancers can be regulated by a number of transcriptional factors, including HIF-1, STAT3, NF-κΒ, and AP-1 and certain oncogenic pathways such as JAK/STAT, RAS/ERK, or PI3K/AKT/MTOR (see Figure 2). The gene discussed is SOAT1; the disease is cancer.