DNAzymes(Dzs) are single-stranded DNA catalysts that specifically cleave the mRNA of targeted genes.Compared with other gene-silencing technologies,such as ribozymes,antisense oligonucleotide and small interference RNA(siRNA),DNAzymes have several advantages,including small molecular weight,diversity,low cost and relative stability in serum.With the evolution of molecular technology,the first DNAzyme was generated in vitro in 1994.From then on,DNAzymes have been studied in order to understand their structures,chemistry and biological applications.Particularly,DNAzymes have been widely applied as a new interference strategy in the treatment of many conditions,including cancer,viral diseases,and cardiovascular diseases.This review mainly summarizes the use of DNAzymes in the areas of cancer research and therapy.
Many human tumor cells are characterized by overexpression or mutation of epidermal growth factor receptor (EGFR). Emerging evidence indicates that EGFR, as well as some of its downstream components, can translocate to the nucleus and play roles in transcriptional regulation, signaling conduction and repair of DNA double strands breaks (DSBs). EGFR in its nuclear manifestation promotes DSB repair by interacting with proteins including DNA-PK, ATM, Rad51 and BRCA1, involved in DSB repair, via the PI3K-Akt and Ras-Raf-MAPK pathways. DNA damage repair in tumor cells is emerging as an attractive target in radiotherapy and chemotherapy. Interruption of EGFR functions, or those of its downstream components, presents a promising strategy for confounding DNA damage repair in tumor cells.
LU JingChenYANG LiFangTAO YongGuangSUN LunQuanCAO Ya