We identified YKL-40 as the main marker for verifying the influence of tumor cells grown in contact with healthy cells, and we found that YKL-40 may have synergistic effects: in HFs, it can act similarly to insulin-like growth factor-1, leading to an inflammatory condition and promoting an up-regulation of MMP-1 expression, remodeling the ECM. Here, CHI3L1 is linked to Hand-foot syndrome.