Glioblastoma is the most prevalent and deadliest type of brain cancer, and each year around 10,000 individuals in the U.S. are diagnosed with the disease.
Now, researchers have found a protein that may provide insight into how the disease moves and invades nearby healthy brain tissue.
In addition, the researchers suggest that a cost-effective FDA-approved drug already on the market could slow movement of these deadly cancer cells. The study is published May 1 in the online, open-access journal PloS Biology.
Lead author of the study, Alfredo Quinones-Hinojosa, M.D., an associate professor of neurosurgery and oncology at the Johns Hopkins University School of Medicine, explains:
"The biggest challenge in brain cancer is the migration of cancer cells. We can't control it. If we could catch these cells before they take off into other parts of the brain, we could make malignant tumors more manageable, and improve life expectancy and quality of life. This discovery gives us hope and brings us closer to a cure."
According to Quinones, the life expectancy after being diagnosed with glioblastoma is only 15 months. In addition, surgical cures are virtually impossible as the disease metastasizes so rapidly and advances in chemotherapy and radiation have been slow.
In order to find ways to prevent or limit the spread of the disease, the team focused on NKCC1 in human tumor cells in the lab and in tumor cells injected into mice.
NKCC1 is a protein that transports sodium, potassium and chloride ions, together with water and controls cell volume.
The researchers discovered that NKCC1 makes it easier for cancerous cells to move through tissue and that tumor cells were able to travel faster and further the more present the protein was in the glioblastoma cells. In addition, the team found that when NKCC1 was not present, the cells were able to attach themselves to surrounding cells, as they had larger focal adhesions keeping them more anchored in place. Quinones notes that smaller focal adhesions made cells more mobile and allowed them to travel further.
According to Quinones, the team was able to slow the migration of tumor cells by blocking the protein using diuretic bumetanide - a simple water pill commonly used to reduce fluid retention and swelling. He explains: less mobility means less invasion of surrounding tissue.
Quinones explains that if the cells were made less invasive it would be easier to surgically remove the tumors.
Furthermore, the team were able to correlate human tumor grade with levels of the protein. They found that the less aggressive the tumor, the smaller the amount of NKCC1 present in the cells. This finding indicates that the protein may not only contribute to the increased invasiveness of tumors, but also serve as a potential marker for diagnosis.
Written By Grace Rattue