Selective EV Protein Sorting and Pathway Perturbation in AML Upon Synergistic FLT3 and Hedgehog Pathway Inhibition

Area of Science:

• Oncology
• Molecular Biology
• Cell Biology

Background:

• Acute myeloid leukaemia (AML) is a blood cancer with poor outcomes, often involving FLT3 mutations.
• Extracellular vesicles (EVs) from AML cells promote a supportive microenvironment and chemoresistance.
• Hedgehog signalling and GLI expression are implicated in AML pathogenesis.

Purpose of the Study:

• To investigate the synergistic effect of FLT3 inhibitor Crenolanib and Hedgehog pathway inhibitor HPI-1 in AML.
• To analyze proteomic changes in AML cells and EVs upon combined inhibition.
• To understand how Crenolanib affects EV cargo and leukaemia niche formation.

Main Methods:

• Comparative proteomics of AML cell lines (MOLM-14, MV4-11) and patient-derived EVs.
• Treatment with Crenolanib (FLT3 inhibitor) and HPI-1 (Hedgehog pathway inhibitor).
• Analysis of cellular and EV proteomes to identify pathway alterations.

Main Results:

• Combined Crenolanib and HPI-1 treatment demonstrated synergistic effects in AML cell lines.
• Proteomic analysis revealed significant alterations in cellular and EV proteomes.
• Crenolanib selectively inhibited the transport of ribosomal proteins (e.g., RPS26, RPL27A) and ErbB pathway proteins (e.g., GAB1, GRB2, SHC1) to EVs.
• EVs from AML patients showed distinct proteomic profiles compared to healthy donors.

Conclusions:

• Combined inhibition of FLT3 and Hedgehog signalling offers a potential therapeutic strategy for AML.
• Crenolanib interferes with leukaemia niche formation by modulating EV composition.
• Ribosomal and ErbB signalling pathways are key targets for AML therapy via EV modulation.