Characterization of human maligant melanoma cell lines. I. Morphology and growth characteristics in culture.

Seven human malignant melanoma lines were maintained in vitro for various periods of time. One line, established in this laboratory from a metastatic solid tumor by repeated treatment of the primary outgrowth with 0.02 percent EDTA, allowed a continuous culture of melanoma cells free of fibroblasts. By light microscopy, cells in each line could be classified into one of three morphologic types: elongated dendritic, cuboidal, or triangular dendritic. Four of the seven lines exhibited various degrees of pigmentation. The growth pattern was determined by plating efficiency and saturation density for each line. Cytogenetic analysis with the fluorescent banding technique revealed only human chromosomes with gross aneuploidy. Major marker chromosomes specific for each line were identified. None of the parameters studied showed any correlation or interdependence with one another, except for an association of elongated dendritic morphology with poor plating efficiency and low saturation density.