DNA repair mechanisms of tumor cells and chemotherapy sensitivity

DNA damage caused by chemotherapeutic drugs plays an important role in the tumor chemo- therapy.The DNA repair pathways that are activated in response to DNA damage induce resistance to chemo-therapeutic drugs or radiation and depress the effect of these agents on tumor cells.Down-regulated DNA repair capacity has shown a better effect through inducing tumor cell hypersensitivity to chemotherapeutic drugs.It has emerged as an important comprehensive approach by down-regulated expression of DNA repair genes in the treatment of cancer. Key words: DNA repair ;  Chemosensitivity ;  Drug resistance ;  Polymorphism,single nucleotide ;