APOBEC3B Does Not Promote Tumor Progression in Tp53 Hemizygous Mice

Area of Science:

• Oncology
• Genetics
• Molecular Biology

Background:

• APOBEC3B (A3B) is a source of somatic mutations in human cancers, linked to tumor progression.
• The role of A3B-induced mutations in accelerating tumor progression remains unclear.

Purpose of the Study:

• To investigate if APOBEC3B (A3B) overexpression accelerates tumor development.
• To establish and validate a mouse model for studying A3B's role in tumorigenesis.

Main Methods:

• Generated a single-copy A3B transgenic mouse model via microinjection.
• Validated A3B expression and activity in various tissues and tumors.
• Interbred A3B mice with Tp53 hemizygous and homozygous mice for tumor progression analysis.

Main Results:

• A3B expression and deaminase activity were confirmed in the transgenic mice.
• No significant difference in tumor development or survival was observed between A3B-expressing and non-expressing Tp53 hemizygous mice.
• Tumors with A3B expression showed increased high-VAF mutations, but not the APOBEC signature.

Conclusions:

• A Cre-inducible A3B transgenic mouse model with a single A3B gene copy was successfully developed.
• A3B overexpression did not accelerate tumor development in Tp53 hemizygous mice.
• The validated A3B mouse model is a valuable tool for future cancer research.