REC-1/STAT3 Reporter (Luc) cells are derived from the human B-cell lymphoma cell line REC-1 by stably integration of a STAT3 firefly luciferase reporter construct. REC-1 is derived from a patient with mantle cell lymphoma (MCL), making it a valuable model for studying this specific type of lymphoma. REC-1 cells are used to investigate the molecular pathways involved in MCL pathogenesis, including the role of cyclin D1 in cell cycle regulation, as well as to evaluate the efficacy of new therapeutic agents, including chemotherapy and targeted therapies. REC-1/STAT3 Reporter (Luc) cells stably express firefly luciferase under the control of the STAT3 response elements, can be used for monitoring the activity of STAT3 signaling pathway.