DNA polymerase theta (Polθ): a novel candidate for targeted cancer therapy

Area of Science:

• Molecular Biology
• Genetics
• Cancer Research

Background:

• DNA double-strand breaks (DSBs) represent critical genomic damage.
• Nonhomologous end joining (NHEJ) and homologous recombination (HR) are primary repair pathways, with microhomology-mediated end joining (MMEJ) acting as a backup.
• MMEJ is dependent on DNA polymerase theta (Polθ), hence its alternative name, Polθ-mediated end joining.

Purpose of the Study:

• To review the structure, function, and expression of Polθ in tumorigenesis.
• To highlight synthetic lethal strategies targeting Polθ.
• To discuss Polθ-based drug development, clinical translation, and future research directions.

Main Methods:

• Literature review of Polθ's role in DNA repair and cancer.
• Analysis of Polθ expression patterns in normal and cancerous tissues.
• Examination of current therapeutic strategies and clinical trials involving Polθ inhibitors.

Main Results:

• Polθ is overexpressed in many cancers, unlike its low expression in normal tissues, identifying it as a potential therapeutic target.
• Polθ inhibitors and related strategies are rapidly advancing, with ongoing clinical trials.
• Synthetic lethality approaches exploiting Polθ dependency show therapeutic promise.

Conclusions:

• Polθ is a critical factor in MMEJ repair and a viable target for cancer therapy.
• Targeting Polθ offers a promising strategy for developing novel anti-cancer drugs.
• Further research is needed to overcome current limitations and advance Polθ-targeted cancer treatments.