Autophagy Targeting and Hematological Mobilization in FLT3-ITD Acute Myeloid Leukemia Decrease Repopulating Capacity...

Area of Science:

• Hematology
• Cancer Biology
• Molecular Oncology

Background:

• FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutations are common in acute myeloid leukemia (AML).
• Tyrosine kinase inhibitors (TKIs) targeting FLT3-ITD can induce remission but often fail to prevent relapse due to resistant leukemic-initiating cells.
• The hematopoietic niche plays a role in AML cell persistence and resistance to therapy.

Purpose of the Study:

• To investigate the role of Vps34 in FLT3-ITD AML.
• To evaluate Vps34 inhibition as a strategy to overcome TKI resistance and prevent relapse in FLT3-ITD AML.
• To assess the combination of Vps34 inhibition with stem cell mobilization for AML treatment.

Main Methods:

• In vitro studies mimicking the hematopoietic niche using low oxygen cultures.
• Ex vivo analysis of AML blasts treated with Vps34 inhibitors.
• In vivo studies using FLT3-ITD AML cell lines in mice, treated with gilteritinib (FLT3 TKI) and/or Vps34 inhibitors, with or without G-CSF and AMD3100 mobilization.

Main Results:

• Vps34 inhibition decreased the repopulating capacity of FLT3-ITD AML cells in vitro.
• Ex vivo, Vps34 inhibition led to slower proliferation recovery and increased apoptosis in AML blasts.
• In vivo, FLT3 TKI treatment induced remission but was followed by rapid relapse; Vps34 inhibition significantly reduced relapse rates, especially when combined with G-CSF and AMD3100 mobilization.

Conclusions:

• Vps34 plays a critical role in the survival and repopulating capacity of FLT3-ITD AML cells.
• Vps34 inhibition is a promising strategy to target persistent leukemic stem cells and prevent relapse in AML.
• Combining Vps34 inhibition with stem cell mobilization agents offers a potential therapeutic window to eradicate residual disease and improve outcomes in FLT3-ITD AML.