Angiogenesis by human melanoma and breast cancer cells.

The induction of new vasculature is essential for tumor growth and survival. Through studies of the angiogenic properties of human breast cancer and melanoma cell lines by implantation in rabbit cornea, results show that both breast tumor and melanoma cells produce an angiogenic factor. Melanoma cells had approximately twice the activity compared to breast tumor cells. Initiation of angiogenesis by 1 X 10(6) melanoma cells occurred in 3 days, reached maximum at 7 days, and resolved in 21 days. Implantation of 2 X 10(6) breast tumor cells initiated angiogenesis in 6 days, reached maximum in 10 days and resolved in 24 days. The difference in the time of angiogenic induction may be related to the aggressiveness of each tumor type.