Analysis of expression and soluble form of intercellular adhesion molecule-1 in malignant melanoma

The effects of interferon (IFN) on the expression of ICAM-1 in human melanoma cell lines and the shedding of ICAM-1 into spent media were investigated using an indirect binding assay and a double determinant immunoassay (DDIA). While IFN increased the level of expression of ICAM-1 on melanoma cell lines, the susceptibility to IFN differed according to cell line. The enhancing effect of IFN-gamma was concentration-dependent, and it exceeded those of IFN-alpha and IFN-beta. Shedding of ICAM-1 into spent media was detected effectively, and the results agreed well with the expression of ICAM-1 on melanoma cells. Immunostaining of the surgically removed melanoma lesions was positively correlated with the thickness of the primary lesion. The expression of ICAM-1 in primary melanoma lesions was inversely correlated with the disease-free interval. The circulating ICAM-1 with stage 4 melanoma patients significantly exceeded that of stage 1-3 melanoma patients. These observations suggest that ICAM-1 in its soluble form may play an important role in host immunities and may be useful in evaluating the prognosis of patients with melanoma.