A drug often used to treat renal cell carcinoma, or kidney cancer, also can kill cells from the most common form of childhood brain cancer, according to City of Hope scientists. The finding suggests the drug may be an effective treatment for children battling medulloblastoma.

Fan Yang studied sunitinib’s effect on brain tumor cells. (Photo by Markie Ramirez)

Researchers led by Hua Yu, Ph.D., professor in the Department of Cancer Immunotherapeutics and Tumor Immunology, and Fan Yang, Ph.D., assistant research professor in the Department of Molecular Medicine, found the drug sunitinib stopped growth of medulloblastoma cells in the lab. It also could make them undergo apoptosis, a form of programmed cell death. The study appeared Jan. 6 in the online version of Molecular Cancer Research.

Sunitinib is one in a growing group of drugs called tyrosine kinase inhibitors. It is in the same family as Gleevec, which revolutionized chronic myeloid leukemia treatment by allowing patients to control their disease with a pill.

Currently, sunitinib is approved by the U.S. Food and Drug Administration to treat certain patients with a type of stomach cancer called gastrointestinal stromal tumor. It also is approved for treating kidney cancer that has spread to other parts of the body. It is not yet approved to treat medulloblastoma.

Sunitinib is known to interfere with a number of cell processes that tumors need to grow and develop, including angiogenesis, the process of blood vessel formation. Tumors usually rely heavily on angiogenesis to nourish themselves and grow. By blocking angiogenesis, sunitinib cuts that lifeline to tumors, effectively choking them to death.

In previous research, Yu’s team worked with Robert Figlin, M.D., Arthur and Rosalie Kaplan Professor of Medical Oncology, to show that sunitinib also can prevent activation of a protein called signal transducer and activator of transcription 3, or STAT3. Figlin, who is chair of the Department of Medical Oncology & Therapeutics Research, contributed to the current study, as well.

STAT3 is well-known for its ability to promote cancer growth while protecting tumor cells from the immune system. Blocking STAT3 could make tumor cells more vulnerable.

“Since medulloblastoma cells are known to have elevated STAT3 levels, we wanted to see if sunitinib could kill them by blocking STAT3 activation,” Yu said. “We found it could.”

Medulloblastoma treatment today usually includes surgery and radiation, which can present challenges to children, especially the very young.

The study results suggest sunitinib is worth studying in clinical trials as a potential new treatment for medulloblastoma, according to the researchers.

Other City of Hope authors on the study include Hong Xin, Ph.D., of the Department of Cancer Immunotherapeutics and Tumor Immunology, Michael Hedvat, student in the Irell & Manella Graduate School of Biological Sciences, and summer student Veronica Jove.

The study was supported by a National Institutes of Health grant.