Direct evidence of mitochondrial G-quadruplex DNA by using fluorescent anti-cancer agents.
G-quadruplex (G4) is a promising target for anti-cancer treatment. In this paper, we provide the first evidence supporting the presence of G4 in the mitochondrial DNA (mtDNA) of live cells. The molecular engineering of a fluorescent G4 ligand, 3,6-bis(1-methyl-4-vinylpyridinium) carbazole diiodide (BMVC), can change its major cellular localization from the nucleus to the mitochondria in cancer cells, while remaining primarily in the cytoplasm of normal cells. A number of BMVC derivatives with sufficient mitochondrial uptake can induce cancer cell death without damaging normal cells. Fluorescence studies of these anti-cancer agents in live cells and in isolated mitochondria from HeLa cells have demonstrated that their major target is mtDNA. In this study, we use fluorescence lifetime imaging microscopy to verify the existence of mtDNA G4s in live cells. Bioactivity studies indicate that interactions between these anti-cancer agents and mtDNA G4 can suppress mitochondrial gene expression. This work underlines the importance of fluorescence in the monitoring of drug-target interactions in cells and illustrates the emerging development of drugs in which mtDNA G4 is the primary target.
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan.
Wei-Chun
WC
Huang
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan.
Ting-Yuan
TY
Tseng
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan.
Ying-Ting
YT
Chen
Institute of Biomedical Engineering, National Chung-Hsing University, Taichung 40227, Taiwan.
Cheng-Chung
CC
Chang
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan.
Zi-Fu
ZF
Wang
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan.
Chiung-Lin
CL
Wang
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan.
Tsu-Ning
TN
Hsu
Department of Biochemical Science and Technology, National Taiwan University, Taipei 10617, Taiwan.
Pei-Tzu
PT
Li
Department of Biochemical Science and Technology, National Taiwan University, Taipei 10617, Taiwan.
Chin-Tin
CT
Chen
Institute of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei 10051, Taiwan.
Jing-Jer
JJ
Lin
Department of Otolaryngology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10051, Taiwan.
Pei-Jen
PJ
Lou
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan tcchang@po.iams.sinica.edu.tw.
Ta-Chau
TC
Chang
D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000633:toxicity; D002227:Carbazoles / Q000737:chemistry* / Q000633:toxicity; D002460:Cell Line; D004272:DNA, Mitochondrial / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D054856:G-Quadruplexes; D006367:HeLa Cells; D006801:Humans; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D011726:Pyridinium Compounds / Q000737:chemistry* / Q000633:toxicity
C000606971:3,6-bis(1-methyl-2-vinylpyridinium)carbazole; D000970:Antineoplastic Agents; D002227:Carbazoles; D004272:DNA, Mitochondrial; D005456:Fluorescent Dyes; D011726:Pyridinium Compounds; C000606972:o-BMVC-12C-P