Researchers from Lund University in Sweden have discovered two new types of B-cell precursor acute lymphocytic leukemia (ALL) in children: "DUX4-rearranged" and "ETV6/RUNX1-like." These two new types join the six major types of childhood ALL already classified, including ETV6-RUNX1, TCF3-PBX1, TCF3-HLF, high hyperdiploidy (51-67 chromosome), hypodiploidy (<45 chromosomes), and MLL (KMT2A).
The researchers analyzed the genome of leukemia cells from more than 200 children using next-generation sequencing to examine changes in cancer cells. The study – published in Nature Communications – indicated that the new types of leukemia represent 10 percent of all childhood leukemia.
The first type, DUX4-rearranged, occurs when the inactive DUX4 in blood cells become activated upon gene rearrangement. The second type, ETV6/RUNX1-like, resembles a previously known type of childhood leukemia, but is caused by other genetic mutations.
"Finding the critical mutations in the diseased cells are an important condition for understanding the mechanisms of the disease and ultimately discovering new therapies," said Thoas Fioretos, a professor and senior consultant at the Division of Clinical Genetics and the principal investigator of the study, in a statement. The researchers said they hope these findings can lead to improved diagnosis and monitoring of this patient population and lead to new treatment options.
Source: Lilljebjörn H, Henningsson R, Hyrenius-Wittsten A, et al. Identification of ETV6-RUNX1-like and DUX4-rearranged subtypes in paediatric B-cell precursor acute lymphoblastic leukaemia. Nature Comm. 2016 June 6. [Epub ahead of print]