Brain Cancer Research Goes Viral

An enzyme known as chondroitinase might help oncolytic viruses (cancer-fighting viruses) more effectively destroy cancer cells in brain tumors by clearing out protein molecules that deter the virus’s mission.

While we normally associate viruses with negative connotations, scientists at Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and the Richard J. Solove Research Institute show for the first time that cancer-targeting viruses with the enzyme chondroitinase, which is derived from the intestinal bacteria called Proteus vulgaris, can spread more efficiently through tumors. In doing so, the enzyme removes sugar chains that extend from molecules called proteoglycans that fill the spaces between cells.

Researchers injected human glioblastoma (brain tumor) cells just under the skin of mice. After tumors developed, they treated them with the enzyme-laden virus. Two of the eight animals remained tumor-free after 80 days with an overall average survival of 28 days. Mice who were treated with a virus that lacked the enzyme survived an average of 16 days.

In another experiment, mice injected with the enzyme-armed virus survived 32 days versus 21 days in those injected with the virus without the enzyme.

Glioblastoma is the most common and aggressive form of brain cancer in the U.S. population, accounting for more than half of all parenchymal brain tumor cases and 20 percent of all intracranial tumors.