STAT3 and diffuse large B-cell lymphoma: Considering that the immunohistochemical expression of S1PR1 was independently associated with poor clinical outcome of DLBCL patients in the present study, the S1P/S1PR1 pathway is suspected to play a role in contributing to the aggressive behavior of DLBCL and, in addition to STAT3, is considered to be a promising therapeutic target in DLBCL.