RAD51-IN-2 is a small molecule inhibitor targeting the RAD51 protein, which plays a central role in homologous recombination (HR), a key DNA repair pathway. Its primary application lies in cancer research, particularly in the development of strategies to sensitize tumor cells to DNA-damaging treatments such as chemotherapy and radiation. By inhibiting RAD51, RAD51-IN-2 disrupts the repair of DNA double-strand breaks, leading to increased genomic instability and cell death in cancer cells, especially those already deficient in other DNA repair mechanisms.

This compound is widely used in studies exploring synthetic lethality, particularly in cancers with BRCA1 or BRCA2 mutations, where HR is already compromised. It shows potential in overcoming resistance to PARP inhibitors, another class of drugs exploiting DNA repair deficiencies. Researchers also use RAD51-IN-2 to probe the mechanisms of DNA repair and to evaluate the role of RAD51 in replication stress and tumor survival. Due to its ability to enhance the cytotoxicity of genotoxic agents, it is being investigated in combination therapies to improve treatment efficacy in resistant or aggressive cancers.