What does targeting blood vessels have to do with immunotherapy?

Malignant tumors hijack the circulatory system by forming new blood vessels to sustain tumor growth in a process called angiogenesis. Newly targeted immunotherapies are geared towards interfering with pro-angiogenic signals from tumors, aiming to delay their growth and even cause them to shrink. Anti-angiogenic immunotherapy also prevents large tumors from metastasizing. Drugs which induce oxygen starvation primarily act through the vascular endothelial growth factor (VEGF) signaling pathway.1 Additional information on immunotherapy can be found in our resource center here.

1. R.R. Ramjiawan, et al., "Anti-angiogenesis for cancer revisited: Is there a role for combinations with immunotherapy?" Angiogenesis 20(2): 185-204, 2017.