DNA Mismatch Repair and Occurrence and Therapy of Cancer
DNA错配修复与癌症的发生及治疗

DNA mismatch repair (MMR) primarily corrects mismatched or unpaired bases incorporated by DNA polymerase, increasing the overall fidelity of DNA replication. DNA MMR system not only ensures the precision of chromosomal replication and maintains genomic stability by correcting the mismatches during the replication and recombination, but also eliminate cancer cells by promoting apoptosis of cells with severely damaged DNA. Defective mismatch repair proteins result in genomic instability, elevated mutation rate and increased incidence of various cancers. It has been found almost universally that while cells that are proficient in MMR are sensitive to chemical agents, cells that are deficient in MMR are more resistant to killing by these agents. While MMR-mediated apoptosis is important for tumor suppression, the drug resistance property of MMR-deficient cells raises concerns for cancer chemotherapy. The genomic maintenance capability of MMR by both its repair and apoptotic functions underscores the importance of the MMR pathway in cancer biology and molecular medicine.