title: Specific repression of mutant K-RAS by 10-23 DNAzyme: sensitizing cancer cell to anti-cancer therapies.
abstract: Point mutations of the Ras family are frequently found in human cancers at a prevalence rate of 30%. The most common mutation K-Ras(G12V), required for tumor proliferation, survival, and metastasis due to its constitutively active GTPase activity, has provided an ideal target for cancer therapy. 10-23 DNAzyme, an oligodeoxyribonucleotide-based ribonuclease consisting of a 15-nucleotide catalytical domain flanked by two target-specific complementary arms, has been shown to effectively cleave the target mRNA at purine-pyrimidine dinucleotide. Taking advantage of this specific property, 10-23 DNAzyme was designed to cleave mRNA of K-Ras(G12V)(GGU-->GUU) at the GU dinucleotide while left the wild-type (WT) K-Ras mRNA intact. The K-Ras(G12V)-specific 10-23 DNAzyme was able to reduce K-Ras(G12V) at both mRNA and protein levels in SW480 cell carrying homozygous K-Ras(G12V). No effect was observed on the WT K-Ras in HEK cells. Although K-Ras(G12V)-specific DNAzymes alone did not inhibit proliferation of SW480 or HEK cells, pre-treatment of this DNAzyme sensitized the K-Ras(G12V) mutant cells to anti-cancer agents such as doxorubicin and radiation. These results offer a potential of using allele-specific 10-23 DNAzyme in combination with other cancer therapies to achieve better effectiveness on cancer treatment.
authors.affiliation: Institute of Biotechnology in Medicine, Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei 11221, Taiwan, ROC.
authors.forename: Szu-Hsien
authors.initials: SH
authors.lastname: Yu
authors.forename: Tong-Hong
authors.initials: TH
authors.lastname: Wang
authors.forename: Lo-Chun
authors.initials: LC
authors.lastname: Au
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001483:Base Sequence; D045744:Cell Line, Tumor; D021881:DNA, Catalytic / Q000235:genetics / Q000494:pharmacology*; D004277:DNA, Single-Stranded / Q000235:genetics / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy* / Q000201:enzymology; D015689:Oncogene Protein p21(ras) / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D017354:Point Mutation; D012333:RNA, Messenger / Q000378:metabolism; D014162:Transfection
chemical_list: D000970:Antineoplastic Agents; D021881:DNA, Catalytic; D004277:DNA, Single-Stranded; D012333:RNA, Messenger; C402582:RNA-cleaving DNA 10-23; D015689:Oncogene Protein p21(ras)