Abstract A202: RNAi as a tool to identify novel molecular vulnerabilities in myeloid leukemias

Abstract

Abstract Therapies and outcomes of patients with Acute Myeloid Leukemia (AML) and advanced myelodysplastic syndrome (MDS) remain very poor and AML is one of the deadliest cancers in relation to incidence. Mostly, because critical targets regulating myeloid cell viability have not been identified. Genomic profiling approaches, including gene expression or sequencing may identify genes and proteins involved in leukemogenesis. However candidates identified with these more “traditional” methods may not necessarily be good drug targets or represent molecular vulnerabilities that can be targeted. Therefore, we pursued a functional genomcis approach using RNAi to identify novel targets that can be exploited for drug development and discovery in order to improve treatment strategies in AML and MDS. First, we established a platform for High-Throughput RNAi (siRNA) gene silencing in typical difficult to transfect suspension cells. Using reverse lipid based transfection conditions we were able to establish conditions that achieve up to 80–90% transfection as measured by a universal silencing control. After successful establishment of our siRNA platform in 3 cell lines, we performed several siRNA screens of the human kinome and other cancer associated genes (i.e. apoptotic and cell cycle genes) with siRNA's alone or in combination with 5-Azacytidine or Cytarabine. In this abstract we will present our experience with siRNA screens in myeloid cells as well as data to support the tremendous opportunity the RNAi approach holds in identifying direct druggable targets in acute leukemias. Our ultimate goal is to develop a “Functional Genomics Pathway Vulnerability Profiling” in AML. Functional genomics using RNAi provide a fast and attractive approach to identify molecular targets in AML/MDS and this approach holds particular promise to develop and design rational (combination) therapies that can be rapidly translated into the clinic. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A202.