Eradicating disseminated tumors, even in brain, by injecting specific antibodies

MedicalResearch.com eInterview with Ronald Levy, M.D.
Professor and Chief Division of Oncology
Stanford University, 269 Campus Drive
Stanford, California 94305, USA

MedicalResearch.com: What are the main findings of the study?

Dr. Levy: Injection of antibodies that deplete Treg cells directly into a tumor can evoke an immune response that cures  the animal of distant, untreated tumors.

This effect eliminates cancer even in the brain.

The dose of antibodies locally injected can be as low as 1/100 the dose used for systemic injection and therefore should avoid the usual autoimmune side effects of these antibodies.
The antibodies used are directed against CTLA4 and OX40 antigens.

MedicalResearch.com: Were any of the findings unexpected?

Dr. Levy: We did not know that Tregs expressed CTLA4 or OX40 antigens.

This is the case only for Tregs in the tumor and not those in the blood or other body compartments.

MedicalResearch.com: What should clinicians and patients take away from your report?

We may be able eventually to trigger an immune response in the host against their own cancer and to do so with the use of antibodies.

Clinical trials are now under way to test this concept in patients with melanoma, lymphoma and colon cancer.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

We need to find out whether this works in patients with cancer.

Citation:

Depleting tumor-specific Tregs at a single site eradicates disseminated tumors

Aurélien Marabelle, Holbrook Kohrt, Idit Sagiv-Barfi, Bahareh Ajami, Robert C. Axtell, Gang Zhou, Ranjani Rajapaksa, Michael R. Green, James Torchia, Joshua Brody, Richard Luong, Michael D. Rosenblum, Lawrence Steinman, Hyam I. Levitsky, Victor Tse, Ronald Levy

J Clin Invest. 2013; doi:10.1172/JCI64859

Last Updated on March 19, 2014 by Marie Benz MD FAAD