Effects of cortisone with and without heparin on angiogenesis induced by prostaglandin E1 and by S180 cells, and on growth of murine transplantable tumours.

Cortisone acetate, locally applied in sustained-release pellets, is effective in inhibiting angiogenesis induced by prostaglandin E1 in the rabbit cornea. The inhibitory effect of cortisone is not increased by addition of heparin. Similar results were obtained with angiogenesis induced by S180 cells. The effects of cortisone with and without heparin were also studied on 5 transplantable murine tumours: 3 variants of B16 melanoma, Lewis lung carcinoma and fibrosarcoma M4. The effect of cortisone in slowing the growth rate of tumours was modestly potentiated by heparin, but no regression of the tumour mass occurred.