ITPR2 Promotes Acute Myeloid Leukemia Progression Through Calcium-Mediated Mitochondrial Dysfunction

Acute myeloid leukemia (AML) is a hematological malignancy of the myeloid lineage with poor clinical outcomes due to limited targeted therapies. This study elucidates the role of inositol 1,4,5-trisphosphate receptor type 2 (ITPR2) in regulating cell apoptosis by modulating mitochondrial calcium (Ca²⁺) levels and underscores the clinical significance of ITPR2.

ITPR2 expression in patients with AML compared with that of healthy controls using the quantitative real-time PCR (RT-qPCR) method. The role of ITPR2 in AML and its association with immune infiltration levels were investigated through bioinformatics analyses. ITPR2 knockdown in Tohoku Hospital Pediatrics-1 (THP-1) cells were achieved using small interfering RNA (siRNA) and 2-aminoethyl diphenylborinate (2-APB), followed by comprehensive molecular characterization employing RT-qPCR, western blotting (WB), cell counting kit-8 (CCK-8) assays, and flow cytometry.

ITPR2 was validated as being highly expressed in patients with AML, and this expression correlated with risk stratification and poor prognosis. Functional enrichment analysis revealed that ITPR2 is involved in Ca²⁺ signaling pathways and mitochondrial-related biological processes, and its expression level was negatively correlated with immune infiltration levels. Knockdown of ITPR2 or inhibition of its activity with 2-APB reduced Ca²⁺ ion concentrations in both the cytoplasm and mitochondria, leading to mitochondrial dysfunction (characterized by elevated intracellular reactive oxygen species (ROS) levels, reduced mitochondrial membrane potential (MMP) levels, and reduced mitochondrial DNA copy number) and eventually AML cell apoptosis.

ITPR2 facilitates AML progression via the Ca²⁺-mitochondrial axis and may serve as a prognostic factor and potential therapeutic target.