An improved method for the establishment of cell lines from primary skin melanomas

Fourteen explants of primary skin melanomas and six explants of lymph node metastases were used to establish melanocyte cell lines, and in all twenty experiments the melanocytes became overgrown by fibroblasts. By contrast, eight melanocyte cell lines without fibroblast contamination were established by mechanical cell separation followed by either direct plating in microwells (five out of thirteen primary tumours and three out of four lymph node metastases) or plating of cells from colonies grown in soft agar (three out of five cases). It was also observed that cell crowding and partial (as opposed to total) replacement of the culture medium during the early steps of culture favoured the growth of tumour cells. This observation suggests that melanoma cells are subjected to an autocrine type of growth regulation.