In pairwise comparisons of the patients with melanoma at stages I, II, and III with control group, all differences in VEGF, MMP-9, TIMP-1, and YKL-40 serum levels between patients and controls were statistically significant except for the difference in YKL-40 concentration between melanoma stage I patients and healthy individuals (Fig. 1). Here, CHI3L1 is linked to melanoma.