MAPK1 and B-cell non-Hodgkin lymphoma: Because ADM is the most commonly used drug for B‐cell NHL treatment and was highly effective in inducing PD‐L1 expression in stromal cells, we used this compound to test whether the ERK pathway might play an important role in mediating drug‐induced PD‐L1 expression in NKtert cells, using both chemical and siRNA approaches.