CX3CL1 and neoplasm: FKN has been reported to elicit anti‐tumor responses by facilitating immune cell infiltration into tumors (Lavergne et al, 2003; Ohta et al, 2005; Xin et al, 2005; Tang et al, 2007; Hyakudomi et al, 2008; Park et al, 2012; Kee et al, 2013; Yamauchi et al, 2020, 2021).