HDR is a double-edged sword in the context of cancer. On one hand, efficient HDR can prevent the accumulation of mutations that lead to cancer. On the other hand, cancer cells often exploit HDR to survive chemotherapy and radiotherapy, which create DSBs to kill cancer cells. Understanding HDR pathways helps in designing better therapeutic strategies. For example, inhibitors of PARP, a protein involved in another DNA repair pathway, are used to treat cancers with defective HDR mechanisms, such as BRCA1/2 mutations.
