ALK and non-small cell lung carcinoma: Importantly, two independent studies showed that ALK inhibitors, alectinib and TAE684, as well as ALK siRNA could effective inhibit the expression of EML4-ALK-induced PD-L1 expression in NSCLC cell models, confirming a positive role of ALK activity on PD-L1 induction in NSCLC [47,48].