CXCR4 and diffuse large B-cell lymphoma: Furthermore, rituximab-induced response was hampered by CXCR4 on the surface of DLBCL cells, with inverse correlation between CXCR4 surface expression level and degree of rituximab sensitivity, for rituximab responsive but not for resistant cell lines; implying that CXCR4 plays a role in rituximab sensitivity but not in intrinsic resistance.