Research led by St . Jude Kid’s Research Hospital has identified three genetic alterations to assist identify high-risk pediatric patients with acute megakaryoblastic leukemia (AMKL) who may benefit from allogeneic stem cell transplants.
The study, which appears nowadays in the scientific journal Nature Genetics , is the largest yet using next-generation sequencing technology in order to define the genetic missteps that drive AMKL within children without Down syndrome. AMKL is a cancer associated with megakaryocytes, which are blood cells that produce the platelets that help blood clot. The genetic basis associated with AMKL in children with Down syndrome was previously determined, but the cause was unknown in 30 to forty percent of other pediatric cases.
“Because long-term survival for pediatric AMKL patients without Lower syndrome is poor, just 14 to 34 %, the standard recommendation by many pediatric oncologists has been to treat every patients with allogeneic stem cell transplantation during their initial remission, ” said senior and co-corresponding author Tanja Gruber, M. D., Ph. D., an associate member of the particular St . Jude Department of Oncology. Allogeneic transplants make use of blood-producing stem cells from a genetically matched donor.
“In this study, we identified several hereditary alterations that are important predictors of treatment success, inch she said. “All newly identified pediatric AMKL sufferers without Down syndrome should be screened for these prognostic signals at diagnosis. The results will help identify which patients require allogeneic stem cell transplants during their first remission plus which do not. ”
The alterations are the fusion genes CBFA2T3-GLIS2, KMT2A and NUP98-KDM5A, which are every associated with reduced survival compared to other pediatric AMKL subtypes. Fusion genes are created when genes break and reassemble. Such genes can lead to abnormal proteins that drive the particular unchecked cell division and other hallmarks of cancer.
Researchers also recommended testing AMKL patients pertaining to mutations in the GATA1 gene. GATA1 mutations are a characteristic of AMKL in children with Down syndrome, which almost always survive the leukemia. In this study, AMKL sufferers with GATA1 mutations and no fusion gene had exactly the same excellent outcome. “The results raise the possibility that pediatric AMKL patients without Down syndrome who have mutations within GATA1 may benefit from the same reduced chemotherapy used to deal with the leukemia in patients with Down syndrome, inch Gruber said.
The revised AMKL analysis screening and treatment recommendations are being implemented at St Jude.
AMKL is rare in adults, yet accounts for about 10 percent of pediatric acute myeloid leukemia (AML). This study involved next-generation sequencing of the entire exome or RNA of 89 pediatric AMKL individuals without Down syndrome. The patients were treated from collaborating institutions in the U. S., Europe and Asia.
Along with the sequencing data, researchers analyzed patients’ gene manifestation and long-term survival. The results showed that non-Down symptoms pediatric AMKL can be divided into seven subgroups in line with the underlying genetic alteration, pattern of gene expression plus treatment outcome.
The AMKL subgroups are the newly identified HOX subgroup. About 15 percent from the 89 patients in this study were in the HOX subgroup, which is characterized by several different HOX fusion genes. Normally HOX genes help regulate development, but HOX alterations are already reported in other types of leukemia.
Investigators furthermore identified cooperating mutations that help to fuel AMKL in various subgroups. The cooperating mutations include changes in the RB1 gene and recurring mutations in the RAS and JAK paths in cells. The alterations have been reported in other malignancies.
Materials provided by St . Jude Children’s Research Hospital . Note: Content may be edited for style and duration.