Immunotherapy May Inhibit Tumor Growth
Combination of immune stimulants and regulatory molecules blocks angiogenesis
THURSDAY, Dec. 16 (HealthDay News) -- A combination therapy of immune stimulants and regulatory molecules appears to block angiogenesis critical to tumor development, according to research published in the Dec. 15 issue of Cancer Research.
Jonathan Schoenfeld, M.D., of Harvard Medical School in Boston, and colleagues analyzed tumor and blood samples from patients who had responded to a combination treatment of immune stimulants and regulatory molecules.
The researchers found that the combination therapy stimulated a host response that inhibited tumor blood vessels. The patients' antibodies to angiopoietin-1 and angiopoietin-2 blocked Tie-2 binding, downstream signaling, endothelial cell tube formation, and macrophage chemotaxis, while antibodies to macrophage inhibitory factor attenuated matrix metalloproteinase-9 production and macrophage Tie-2 expression.
"Together, these results delineate an immunotherapy-induced host response that broadly targets the angiogenic network in the tumor microenvironment," the authors write.