Understanding the FLT3-ITD maintenance and relapse pathways by RNAi screens

Tandem duplication mutations in the tyrosine kinase receptor 3 (FLT3-ITD) are a sign of poor prognosis for patients, who are normally treated with FLT3 inhibitors such as gilteritinib. Given the importance of this mutation in the prognosis and relapse of patients, we wanted to screen a list of gene candidates related to FLT3-ITD maintenance and development.

A list of genes was generated from RNASeq data (patient and cell lines), epigenetic landscape and gene response to inhibitors. An dox-inducible lentiviral RNAi drop-out screen was used to test the importance of these genes in the maintenance and gilteritinib resistance of MOLM-14 and MV4;11 (FLT3-ITD+) cell lines both in vitro and in vivo. Notably, sgRNAs for more than 20% of the candidate genes were either depleted or enriched in the screen providing functional proof for preselection strategy of candidates. Candidates include with e.g., BCL2, DUSP5 and AIF1L regulators of cell viability, cell signalling and of the cytoskeleton that are currently further investigated both in vivo and in vitro in cell lines and in patient PDX.

Publication History

Article published online:
17 May 2022