PRPS1 and acute lymphoblastic leukemia: To screen chemotherapeutic drugs which can overcome PRPS1 mutant‐driven drug resistance, we performed cell viability assay by measuring half maximal inhibitory concentration (IC50) to analyze the effects of PRPS1 wild‐type (WT) and PRPS1 mutants (A190T and S103T) in response to multiple chemotherapeutic drugs in Reh human ALL cell line.