Infant acute leukemias (arising in children less than one year old) makes up a unique subset of leukemias that are particularly lethal and that are characterized by recurrent mutations in one gene. This gene has been termed the mixed lineage leukemia (or MLL) gene, and mutations in MLL are found in the majority of infant leukemias as well as in smaller proportions of childhood and adult leukemias. The mutations in MLL are intriguing, because they are the result of chromosomal breakage which abnormally joins the MLL gene to a variety of partner genes.

Delay in blood cell count recovery after chemotherapy is the most commonly observed toxicity in pediatric acute myeloid leukemia (AML), and 80% of patients develop severe toxicities during treatment.  Delay in therapy due to a low white blood cell (WBC) count places individuals at risk for severe infections, and is associated with an increased mortality.  We are investigating genetic markers for risk for AML treatment-related toxicities, such as unexpectedly prolonged periods of low WBC count after chemotherapy.  The genetic marker we are studying is an enzyme called telomerase, which maint

Pediatric acute lymphoblastic leukemia (ALL) is the most common childhood cancer, with approximately 2400 new cases/year in the United States.  Patients are put into remission using chemotherapy, and over 70% stay in remission.  If a patient relapses, it is hard to achieve a long-term cure, and they often succumb to their disease.  The best chance for maintaining a remission after relapse is often through a stem cell transplant (SCT), in which the patient's bone marrow is replaced with hematopoietic stem cells (HSC) from either a donor or cord blood unit.  Part of the reason a cure is achie

Cure rates of childhood acute lymphoblastic leukemia (ALL) have improved dramatically in the past decades. However, in 15-20% of children with ALL, the leukemia comes back after therapy and most children who relapse eventually succumb to the disease. Relapsed ALL is in fact one of the leading cause of death in children with cancer. Most importantly, ALL relapse is significantly more frequent in Hispanic children compared to Caucasians, and the underlying causes are largely unknown.

After brain cancer, the most common solid tumor in children is neuroblastoma. Some versions of neuroblastoma are highly deadly, with fewer than half of patients cured despite surgery, radiation, high dose chemotherapy, bone marrow transplantation, and treatment with vitamin A forms that cause cells to mature and stop dividing. It is widely believed by most pediatric hematologists/oncologists that we have reached a plateau in our use of these treatments, and further refinements will only bring minimal improvements in increasing patient survival.