Protein 4.1R regulates CCDC26 and impacts myeloid leukemia progression.

Area of Science:

• Hematology
• Molecular Biology
• Oncology

Background:

• Myeloid leukemia involves abnormal myeloid progenitor cell proliferation, with unclear molecular drivers.
• Protein 4.1R (EPB41) is a tumor suppressor in other cancers, but its role in myeloid leukemia is unknown.

Purpose of the Study:

• To investigate the function and molecular mechanism of Protein 4.1R in myeloid leukemia.
• To identify downstream targets and signaling pathways regulated by Protein 4.1R.

Main Methods:

• Knockdown of Protein 4.1R in K562 and HEL leukemia cell lines.
• Transcriptome sequencing to identify downstream molecules.
• RNA pull-down and nuclear-cytoplasmic fractionation to study RNA-protein interactions.

Main Results:

• Protein 4.1R knockdown increased cell proliferation, decreased apoptosis, and promoted S-phase entry.
• CCDC26 was identified as a key downstream long non-coding RNA.
• Protein 4.1R directly binds CCDC26 in the nucleus, inhibiting its cytoplasmic export and subsequent MAPK pathway activation.

Conclusions:

• Protein 4.1R inhibits myeloid leukemia progression by sequestering CCDC26 in the nucleus, thereby suppressing MAPK signaling.
• This mechanism highlights the role of Protein 4.1R-CCDC26 interaction in leukemia pathogenesis.
• Findings provide a theoretical basis for targeting this pathway in leukemia therapy.