ACVR1 and lymphoma: Furthermore, SMAD1 has been long recognized as a chemosensitizer in DLBCL.[49] Recently, Stelling et al. reported that SMAD1 expression restoration by DNA demethylating agent decitabine would suppress DLBCL.[50] Our results align well with these reports and support the critical role of BMP‐ACVR1‐pSMAD1/5 signaling in lymphoma therapy.