Contribution of Microhomology to Genome Instability: Connection between DNA Repair and Replication Stress

Area of Science:

• Molecular Biology
• Genetics
• Cancer Research

Background:

• Microhomology-mediated end joining (MMEJ) is a DNA repair pathway for double-strand breaks (DSBs).
• MMEJ was previously considered a backup to homologous recombination (HR) and canonical nonhomologous end joining (C-NHEJ).
• MMEJ plays a significant role in cancer development and genome instability.

Purpose of the Study:

• To review recent findings on MMEJ's role in genome instability.
• To explore MMEJ's interactions with other DNA repair pathways.
• To discuss MMEJ's mechanistic models, its connection to microhomology-mediated break-induced replication (MMBIR), and its therapeutic potential in cancer.

Main Methods:

• Literature review of MMEJ mechanisms and functions.
• Analysis of MMEJ's involvement in DNA DSB repair.
• Exploration of MMEJ's implications in homologous recombination-deficient cancers.

Main Results:

• MMEJ contributes significantly to genome instability.
• MMEJ interacts with and influences other DNA repair pathways.
• MMEJ is upregulated in homologous recombination-deficient cancers, highlighting its importance.

Conclusions:

• MMEJ is a critical DNA repair pathway with implications for cancer.
• Understanding MMEJ's mechanisms and interactions can reveal new therapeutic targets.
• Targeting MMEJ via synthetic lethality presents a promising strategy for cancer treatment.