Assessing risk factors and health disparities in pediatric Acute Lymphoblastic Leukemia 2364

Abstract Description Acute Lymphoblastic Leukemia (ALL) is a hematologic cancer that affects white blood cells within the blood and bone marrow of adults and children. Currently, ALL is one of the most prevalent malignancies in pediatric patients and is most seen among Caucasian and Hispanic descent with lower incidence in African American children. Our study investigated the racial/ethnic differences and risk factors for relapse that could potentially influence the expression of immune cell receptors in ALL outcomes within pediatric patients. The whole blood was collected from 42 pediatric ALL subjects at diagnosis and post-induction chemotherapy and 20 healthy subjects, and expression was determined at the mRNA and cell surface protein level. mRNA and cell surface protein expression of various immune receptors including 2B4, CS1, LLT1, Nkp30 and NKp46 were analyzed in pediatric ALL subjects by qRT-PCR and flow cytometry. ALL patients with a very-high risk of relapse showed increased expression of LLT1 and CS1 on NK cells and monocytes as compared to high-risk or standard-risk patients at diagnosis and post-chemotherapy respectively. Also, there was a significantly increased expression of LLT1 and CS1 on T cells of Caucasians as compared to Hispanics and African Americans at diagnosis. The altered expression of immune receptors in racial/ethnic and risk-stratified groups may provide insights into T-cell- and NK-cell-mediated immune surveillance of pediatric ALL. Funding Sources Team Connor Childhood Cancer Foundation Topic Categories Tumor Immunology: Cellular Responses and Tumor Microevironment (TIME)