Researchers at Huntsman Cancer Institute (HCI) at the University of Utah seem to have shed new light on Ewing’s sarcoma. This sarcoma is known to be a frequent fatal bone cancer which usually afflicts children and young adults. They discovered that patients with poor outcomes seem to have tumors with high levels of a protein called as GSTM4, which may control the effects of chemotherapy.
Ewing’s sarcoma appears to be the second most widespread bone cancer in children and adolescents. The five-year survival rate seems to be considered poor at approximately 30 percent if the cancer has multiplied by the time it is diagnosed. Also, there seems to be a poorer prognosis for patients who have suffered a relapse.
“Doctors and researchers have long known that certain Ewing’s sarcoma patients respond to chemotherapy, but others don’t even though they have the same form of cancer. Our research shows that GSTM4 is found in high levels among those patients where chemotherapy doesn’t seem to work. It’s found in low levels in patients where chemotherapy is having a more positive effect,” says director of HCI’s Center for Children’s Cancer Research, and a Jon and Karen Huntsman Presidential Professor in Cancer Research, Stephen Lessnick, M.D., and Ph.D.
Lessnick further added, “GSTM4 doesn’t seem to suppress the benefits of all chemotherapy drugs, just certain ones. A GSTM4-based test could help to identify the best therapy for each individual patient.”
For the purpose of better understanding this criterion, researchers focused on an abnormal protein known as EWS-FLI, which is noted to be found in nearly all Ewing’s sarcoma tumors.
They discovered that EWS-FLI seems to cause increased amounts of the GSTM4 gene as well as the protein it produces to be expressed in tumors. This was previously unidentified which led them to build the connection between poor outcomes and high levels of GSTM4.
The discovery was known to have been made by focusing on recurring DNA sequences called microsatellites. Microsatellites are at times referred to as ‘junk DNA’ because they are not considered to have a usual role in the genome.
Supposedly, Lessnick along with his team was able to identify GSTM4 by examining how EWS-FLI interacts with certain microsatellites. Lessnick claimed that the next step in research was to focus on testing and treatments which may perhaps lead to better survival rates in patients.
“Personalized medicine is the next frontier in the battle against cancer. We now know all cancers are not the same. By focusing on how these proteins are expressed in individual tumors, we may soon be able to offer the treatment that will work best for each patient, and that could lead to higher cure rates,” he continues.
The research may perhaps result in formation of drugs which could suppress GSTM4 in certain patients. In addition, it could lead to a screening test which will be able to reveal therapies most effective for patients.
The findings of the research have been published in the journal Oncogene.