The Kumar Lab is studying the biology of blood cancers found in children. Our current focus is on two diseases – infant leukemia and Langerhans Cell Histiocytosis (LCH). Leukemia is the most frequent form of childhood cancer. Infants with leukemia face an exceptionally grim prognosis because the pathogenesis of the disease is different than that of leukemia in older children. The majority of leukemias found in infants involve translocations of the MLL gene on chromosome 11q23.

Our lab is studying experimental models of MLL-rearranged leukemia to discover biological pathways that are dysregulated in the leukemic cells. Using knock-in MLL-AF9 mice, we have identified several genes that are abnormally upregulated in hematopoietic cells compared to corresponding wild type cells. These genes and pathways are also up-regulated in leukemia cells of human patients. We are now studying the role of these activated genes in the pathogenesis of leukemia.

Another rare disease most commonly found in children is LCH. Our knowledge and understanding of the pathophysiology of LCH has been limited, hampering the development of specific and effective treatments. In the tumor cells of children with LCH, we identified mutations in the gene MAP2K1, which encodes for the serine/threonine kinase MEK. We are currently investigating the role of these mutations in the pathogenesis of LCH.