ADHESIVE AND MIGRATORY BEHAVIORS OF NEVUS CELLS DIFFER FROM THOSE OF EPIDERMAL MELANOCYTES AND ARE NOT LINKED TO THE HISTOLOGICAL TYPE OF NEVUS

It has been postulated that acquired nevi undergo life span continuous evolution from junctional, presumably in radial expanding phase at th e dermal epidermal junction, to compound and then to dermal nested nev i, In an attempt to correlate the morphology of nevi with biological d ata, we have investigated whether migratory and adhesive phenotypes of nevus cells could account for histological patterns and possible spat iotemporal changes in nevi. Nevus cells were cultured from compound an d dermal nevi and compared to normal epidermal cultured melanocytes fr om children and adults, All nevus cells showed similar in vitro adhesi ve and migratory indexes on laminin-1, laminin-5/nicein, fibronectin, or collagen IV substrates, suggesting that these intrinsic characteris tics do not account for the tendency to dermal nesting and/or to radia l growth along the dermal-epidermal junction, The cells from epidermal and dermal parts of compound nevi migrated similarly across a reconst ituted basement membrane, The results show that intrinsic adhesive and migratory behaviors of nevus cells were not associated with a histolo gical type of nevus, Interestingly, differences in migratory phenotype and intercellular adhesion capacities between nevus cells and normal melanocytes indicated that they could represent different melanocytic cell subpopulations. Finally, melanocytes from adults and children exp ressed similar levels of the same integrins as all nevus cells but sho wed differences in function of both alpha 3 and alpha 6 integrin subun its and in migratory/adhesive behaviors, which may suggest different s tates of melanocyte maturation.