CXCR4 and non-Hodgkin lymphoma: Since a post-treatment decrease in bone marrow-expressed CXCR4 was recently reported to be associated with favorable treatment response and significantly better prognosis in a small cohort of non-Hodgkin lymphoma patients [32], we wanted to investigate the effect of plerixafor (500 μM) and/or rituximab (10 μg/mL) on the cell surface expression level of CXCR4.