A new molecule found in the cancer cells of neuroblastoma – a rare cancer that primarily affects young children – holds the key to developing an effective treatment for the disease, according to a new study published in Cancer Research.
By obtaining and analyzing blood and tumor samples from 26 patients with neuroblastoma, scientists have discovered a molecule – called arginase – which affects the level of arginine found in the area around the tumor.
Arginine is a key energy source for the body’s immune system and acts as one of the building blocks for the body’s functions. Without energy, the body’s immune system becomes lethargic and ineffective.
Neuroblastoma is currently the most common extracranial solid tumor in infancy. More than 650 cases are diagnosed in the US each year, with an estimated 1 case per 7,000 live births.
In neuroblastoma, malignant cancer cells form in certain types of nerve tissue. It most often originates in the adrenal glands, found above the kidneys, but can also be formed around the spine, abdomen, chest and neck area. Symptoms are a result of the tumor pressing on nearby tissue as it grows or by the cancer spreading to the bones
Treatments for the condition have focused on enhancing the body’s natural immune system to produce an anti-neuroblastoma response.
Between 1975 and 2010, the 5-year survival rate for neuroblastoma increased from 86% to 95% for children younger than 1 year. An increase was found in children aged 1-14 years old, with the rate increasing from 34% to 68%.
Researchers have found almost all neuroblastoma cells to have a molecule – GDC – on their surface that distinguishes them from healthy cells. Scientists believe they can use its unique properties by training the body’s immune system to eventually recognize and destroy cancer cells.
However, treatments for neuroblastoma have often been found to be inconsistent. Study author Dr. Francis Mussai, of the University of Birmingham in the UK, says:
“We have known for a while that harnessing the power of the immune system could be an effective way to treat neuroblastoma. But we didn’t know why the immune cells were having such difficulty recognizing and destroying the tumor.”
Speaking to Cancer Research UK, Dr. Mussai likened the effects of neuroblastoma cells to “kryptonite,” which saps Superman of his energy. He explains:
“There didn’t seem to be any direct signal the cancer cells sent to the immune cells. The neuroblastoma cells just acted like kryptonite to the T cells. As soon as they were brought together, all of the normal cancer-fighting abilities of the immune cells were dramatically weakened.”
Study co-author Dr. Carmela De Santo hopes the new findings will pave the way for more new and effective treatments that specifically target the cancer’s kryptonite abilities.
“Now, the challenge is to develop new drugs which stop neuroblastoma from using arginine, and may make immune therapy more effective,” she adds.
Utilizing the body’s immune system to fight cancer is known as immunotherapy. Last month, Medical News Today reported on two studies in which the treatment was used to tackle lung cancer and melanoma.
The treatment has shown early promise in clinical trials, and there is hope that immunotherapy can represent a real breakthrough in the fight against cancer, which is currently the second most common cause of death in the US.
MNT spoke exclusively to Dr. Mussai about the next step following the results of his study. He said he hoped to work along future clinical trials to “understand if immunotherapy can be made more resistant to arginine depletion or if there are ways of targeting arginine by neuroblastoma.”
Written by Peter Lam