Two recent studies demonstrate that natural activators of autophagy (Ery5 and convallatoxin) inhibit angiogenesis. Ery5 treatment
inhibited angiogenesis, reduced HUVEC tube formation and induced cancer cell death .
Convallatoxin (CNT), a natural small molecule
isolated from Antiaris toxicaria, potently induced autophagy in HUVECs, while inhibiting angiogenesis and cell growth .
Interestingly, treatment with VEGF blocked Ery5-induced autophagy and significantly increased cancer cell viability, suggesting
VEGF may play a role in counteracting autophagy to maintain tumor growth.
These results may open a new field of research exploring
how VEGF protects certain types of tumor cells from autophagy-induced cell death. As new research develops potential therapies may
begin to focus on a combination of drugs that activates autophagy while inhibiting VEGF pathways.