CX3CL1 and neoplasm: On the other hand, FKN promotes tumor migration and invasion of circulating tumor cells towards tissues displaying high FKN expression (Korbecki et al, 2020) (Shulby et al, 2004; Marchesi et al, 2008; Erreni et al, 2010; Gaudin et al, 2011; Jamieson‐Gladney et al, 2011; Kim et al, 2012; Marchica et al, 2019).