To investigate the change in the effect of CX3CL1 on cancer cells without a signal peptide and chemokine domain in vitro, we performed MTS assay and Transwell migration assay on MOC2 cells transfected with signal peptide–deleted CX3CL1 plasmids (MOC2Δs-CX3CL1) and MOC2 cells transfected with chemokine domain–deleted CX3CL1 plasmids (MOC2Δcd-CX3CL1) and compared with the MOC2 and MOC2CX3CL1 groups. The gene discussed is CX3CL1; the disease is cancer.