A compound combination screening approach with potential to identify new treatment options for paediatric acute myeloid leukaemia

Abstract

Paediatric acute myeloid leukaemia (AML) is a heterogeneous disease characterised by genetics and morphology. The introduction of intensive chemotherapy treatments together with patient stratification and supportive therapy has resulted in a moderate improvement in patient prognosis. However, overall survival rates remain unacceptably poor, with only 65% of patients surviving longer than 5 years. Recently age-specific differences in AML have been identified, highlighting the need for tailored treatments for paediatric patients. Combination therapies have the potential to improve patient prognosis, while minimising harmful side-effects. In the laboratory setting, identifying key combinations from large drug libraries can be resource-intensive, prohibiting discovery and translation into the clinic. To minimise redundancy and maximise discovery, we undertook a multiplex screen of 80 apoptotic-inducing agents in paediatric AML pre-clinical models. The screen was designed using an all-pairs testing algorithm, which ensured that all pairs of compounds could be tested, while minimising the number of wells used. We identified a combination of ABT-737, a Bcl-2 family inhibitor and Purvalanol A, a CDK inhibitor, as a potential targeted therapy for AML patients with an MLL rearrangement and an FLT3-ITD. Our approach has the potential to reduce resource-intensity and time associated with the identification of novel combination therapies.

Drug Repurposing for Targeting Acute Leukemia With KMT2A (MLL)—Gene Rearrangements

“…In a study using an alternative multiplex screening approach, Lappin et al screened a library of 80 apoptosis-inducing agents for potential combinations with compounds with therapeutic potential for pediatric AML ( Lappin et al, 2020 ). The screening identified ABT-737, a B-cell lymphoma (BCL)-family inhibitor and Purvalanol A, a CDK2 inhibitor, as a combination with therapeutic potential for MLL -rearranged leukemia and internal tandem duplications of the fms-related tyrosine kinase 3 gene (FLT3-ITD).…”

“…This high-throughput screening approach proved very effective, as it combined the selection of a therapeutically highly relevant drug library as step one, and then the application of an all-pairs testing algorithm for identification of novel partners for combination treatments. This methodology achieves the reduction of consumables and time in the laboratory and opens up opportunities identification of novel combination therapies including the repurposing of therapeutic agents ( Lappin et al, 2020 ).…”

Multiplex Screening for Interacting Compounds in Paediatric Acute Myeloid Leukaemia

“…To test all pairings of 384 compounds, 73,536 (=384 × (384 − 1)/2) individual wells would be required using standard approaches. As described previously, an all-pairs testing algorithm, designed in-house, was used to group compounds into pools of 10 compounds per well, allowing all possible pairwise combinations of 384 drugs to be accommodated in 3878 wells [8]. The 3878 10-compound combinations were created using the Echo liquid handling technology (Labcyte); two paediatric AML cell lines (CMK and MV4-11) were treated with the combinations using the optimum dose per drug, and cell viability was assessed at 48 and 72 h. The heatmaps in Figure 1A highlight the Z-score analysis of each of these individual combinations at both time points across each cell line.…”

“…In this study, we demonstrate the utility of a novel multiplex screening approach [8] to identify potential repurposed combination therapies for the treatment of paediatric AML. We identified the combination of glimepiride, a sulfonylurea used in the management of type 2 diabetes mellitus [25]; pancuronium dibromide, a neuromuscular blocking agent [26]; and vinblastine sulfate, a vinca-alkaloid anticancer agent [27], as a potential therapy for paediatric AML.…”

“…Until recently, our understanding of paediatric AML has been influenced by genomic data collated from adult cases. However, high-throughput sequencing of paediatric samples has revealed that paediatric AML is biologically different from adult AML [8,9]. The Therapeutically Applicable Research to Generate Effective Treatments (TARGET) AML initiative provided a comprehensive characterisation of the mutational, transcriptional and epigenetic landscapes of paediatric AML [10].…”