CircSPI1 acts as an oncogene in acute myeloid leukemia through antagonizing SPI1 and interacting with microRNAs

Area of Science:

• Hematology
• Molecular Biology
• Oncology

Background:

• PU.1 (SPI1) is critical for myeloid development; its dysregulation is implicated in acute myeloid leukemia (AML).
• Circular RNAs (circRNAs) represent a novel regulatory layer in gene expression, particularly relevant in complex diseases like AML.

Purpose of the Study:

• To investigate the role of circSPI1, a circRNA derived from the SPI1 gene, in the pathogenesis of AML.
• To elucidate the molecular mechanisms by which circSPI1 influences AML cell behavior and clinical outcomes.

Main Methods:

• Expression analysis of circSPI1 in AML versus normal samples.
• Functional studies involving circSPI1 knockdown in AML cell lines.
• Mechanistic investigations of circSPI1 interactions with proteins (e.g., eIF4AIII) and microRNAs (e.g., miR-1307-3p, miR-382-5p, miR-767-5p).
• Correlation analysis of circSPI1-regulated genes with clinical data from AML patients.

Main Results:

• circSPI1 is significantly upregulated in AML compared to normal counterparts.
• circSPI1 knockdown promotes myeloid differentiation and apoptosis in AML cells, indicating an oncogenic role.
• circSPI1 antagonizes PU.1 translation via eIF4AIII and regulates proliferation/apoptosis through interactions with specific microRNAs, independent of SPI1.
• circSPI1-associated gene expression signatures correlate with patient clinical outcomes.

Conclusions:

• circSPI1 functions as an oncogene in AML, promoting disease progression.
• circSPI1 exerts its oncogenic functions through distinct mechanisms involving translational repression of PU.1 and microRNA sponging.
• circSPI1 represents a potential diagnostic biomarker and therapeutic target for AML.