Virus might fight brain tumors better if armed with bacterial enzyme, study shows

January 13, 2011, Ohio State University Medical Center

New research shows that oncolytic viruses, which are engineered to destroy cancer cells, might be more effective in treating deadly brain tumors if equipped with an enzyme that helps them penetrate the tumor.

The enzyme, called chondroitinase, helps the cancer-killing virus clear its way through the thickets of that fill space between cells and impede the virus's movement through the tumor, say researchers at the Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute who conducted the study.

When tested in animals transplanted with a human glioblastoma, the most common and deadly form of brain cancer, the enzyme-armed virus improved survival by 52 percent compared with controls and in some cases eliminated the tumor entirely.

The findings were published online in the journal Clinical Cancer Research.

"Our results show for the first time that an oncolytic virus with this enzyme can spread more effectively through the tumor and underscores the potential of using chondroitinases to enhance the capacity of oncolytic viruses to destroy ," says study leader Balveen Kaur, associate professor of .

The enzyme is derived from the intestinal called Proteus vulgaris. The enzyme removes sugar chains that branch from molecules called proteoglycans, which fill the narrow spaces between cells. By cutting away these branches, the enzyme clears a path that helps the virus spread through the tumor.

During this study, Kaur and her collaborators injected human glioblastoma cells under the skin of eight animals, and then, after tumors developed, treated the tumors with the enzyme-armed virus. These mice survived an average of 28 days, with two remaining tumor-free after 80 days. Control animals, treated with a virus that lacked the enzyme, survived 16 days.

In another experiment, mice with human gliobastomas transplanted into the brain survived 32 days versus 21 days for control animals, an improvement of 52 percent. Again, two animals lived more than 80 days and showed no trace of the tumor afterward.

Additional studies showed that the enzyme-laden virus had penetrated tumors in the animals' brain significantly better than the enzyme-free control virus.

"Overall, our results indicate that an oncolytic virus armed with this enzyme can have a significantly greater anticancer effect compared with a similar without the ," Kaur says.

Related Stories

Recommended for you

New approach attacks 'undruggable' cancers from the outside in

January 23, 2018
Cancer researchers have made great strides in developing targeted therapies that treat the specific genetic mutations underlying a patient's cancer. However, many of the most common cancer-causing genes are so central to ...

Study: Cells of three advanced cancers die with drug-like compounds that reverse chemo failure

January 23, 2018
Researchers at Southern Methodist University have discovered three drug-like compounds that successfully reverse chemotherapy failure in three of the most commonly aggressive cancers—ovarian, prostate and breast.

'Hijacker' drives cancer in some patients with high-risk neuroblastoma

January 23, 2018
Researchers have identified mechanisms that drive about 10 percent of high-risk neuroblastoma cases and have used a new approach to show how the cancer genome "hijacks" DNA that regulates other genes. The resulting insights ...

Enzyme inhibitor combined with chemotherapy delays glioblastoma growth

January 23, 2018
In animal experiments, a human-derived glioblastoma significantly regressed when treated with the combination of an experimental enzyme inhibitor and the standard glioblastoma chemotherapy drug, temozolomide.

Scientists block the siren call of two aggressive cancers

January 23, 2018
Aggressive cancers like glioblastoma and metastatic breast cancer have in common a siren call that beckons the bone marrow to send along whatever the tumors need to survive and thrive.

Researchers identify a protein that keeps metastatic breast cancer cells dormant

January 23, 2018
A study headed by ICREA researcher Roger Gomis at the Institute for Research in Biomedicine (IRB Barcelona) has identified the genes involved in the latent asymptomatic state of breast cancer metastases. The work sheds light ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.