Cracking the homologous recombination deficiency code: how to identify responders to PARP inhibitors

Area of Science:

• Molecular Biology
• Oncology
• Genetics

Background:

• DNA double-strand breaks are critical DNA damage, necessitating tight repair regulation for cellular integrity.
• Homologous recombination deficiency (HRD) is a defect in a key DNA repair pathway, rendering cancer cells more susceptible to PARP inhibitors (PARPi).
• PARPi have demonstrated efficacy in BRCA-mutated ovarian cancer and are expanding to other cancer types and HRD phenotypes.

Purpose of the Study:

• To review and synthesize existing homologous recombination deficiency (HRD) tests.
• To discuss the challenge of developing reliable HRD tests for patient selection in PARPi therapy.
• To categorize HRD detection methods into three main approaches.

Main Methods:

• Review of existing literature on HRD tests and PARPi sensitivity.
• Categorization of HRD detection strategies based on causes, consequences, and activity.
• Synthesis of information regarding the clinical application of HRD testing.

Main Results:

• PARPi efficacy is linked to HRD, extending beyond BRCA mutations.
• A significant challenge lies in developing accurate tests to identify HRD phenotypes.
• Existing HRD tests fall into three main categories: investigating causes, consequences, or HR activity.

Conclusions:

• Accurate detection of HRD is essential for predicting PARPi sensitivity and guiding patient selection.
• Further development and validation of HRD tests are needed to optimize cancer treatment strategies.
• Understanding the different approaches to HRD detection is key to advancing personalized oncology.