Children and adolescents with metastatic Ewing’s sarcoma have a lower survival rate than those whose cancer cells remain at the primary tumor site. However, a new discovery by researchers at the St. Baldrick’s Foundation and the University of British Columbia offers hope that the cancer can be stopped from spreading to other parts of the body.
The scientists found that these specific cancer cells put on a protective shield to defend themselves as they circulate in the bloodstream, looking for new locations to grow.
“What we found was that Ewing sarcoma cells can develop an antioxidant response that protects them and allows them to survive as they circulate. This is similar to a person in the Arctic having to put on a thick coat before going outside to protect them.” themselves, they are exposed to dangerously harsh conditions under which they may not survive,” said senior author Dr. Poul Sorensen, a BC Cancer scientist and professor of pathology and laboratory medicine at the University of British Columbia.
“The exciting thing about this study is that if we can target the cells in circulation, we may be able to prevent metastasis from occurring. So that’s the really big goal of this research.”
Ewing’s sarcoma is an aggressive form of bone cancer that can be fatal if not caught early enough. The tumors grow in the bones or soft tissue around the bones of the legs, pelvis, ribs, arms, or spine.
When these cancer cells metastasize, they usually spread to the lungs, bone, or bone marrow. While it’s very rare — about 250 children and young adults in the US are diagnosed with Ewing’s sarcoma each year — it’s the second most common bone cancer in this population.
Although Ewing sarcoma is not a hereditary cancer, there are chromosomal changes that occur after birth. A child’s own genetic makeup and prenatal development determine whether he or she will have it or not, according to St. Jude Children’s Research Hospital.
The most common symptoms are swelling and pain around the tumor site, low-grade fever, fatigue, weight loss, bone pain that worsens during exercise or at night, and limping. The challenge in getting a quick diagnosis is that these symptoms are often first attributed to growing pains, infection, or another medical condition.
Seventy percent of children with this cancer are cured with current treatment methods, usually chemotherapy first and then surgery to remove the cancer. However, if it does spread, the survival rate is less than 30% percent.
dr. Sorensen explained that not all cancer cells can become metastatic. Previous research has shown that there may be genetic reasons why certain tumors mutate and spread, while others do not.
What the study published in Cancer Discovery showed is that when a naturally occurring gene on the surface of the cancer cells, known as IL1RAP, is turned on, it allows the cell to create a protective shield that makes it easier to spread.
dr. Haifeng Zhang, a postdoctoral researcher from the University of British Columbia in Dr. Sorensen at BC Cancer, explained that IL1RAP is rarely expressed in normal tissue and this allows them to develop treatments that target the proteins without damaging the protein. all non-cancerous cells.
Sorensen and Zhang’s colleagues at the St. Baldrick’s Foundation and the National Cancer Institute Pediatric Immunotherapy Discovery and Development Network are working to develop antibodies that can target IL1RAP.
dr. Sorenson said their research shows that these antibodies bind to the outside of the cell and actually kill it. Researchers hope to have a new immunotherapeutic treatment for Ewing sarcoma ready for clinical trial within a year or two.
Other studies are also investigating whether the same shielding behavior is used by other types of cancer cells, including acute myeloid leukemia, melanoma, pancreatic adenocarcinoma, central nervous system tumors, and in some types of lung and breast cancers.
Pediatricians urge parents to ensure that their children and teens are checked regularly and follow up on any referrals to specialists. When Ewing sarcoma is diagnosed early enough, treatments are more successful, researchers emphasize.