Some metallo-supramolecular helical assemblies with size, shape, charge and amphipathic architectures similar to short cationic α-helical peptides have been shown to target and stabilise DNA G-quadruplexes (G4s) in vitro and downregulate the expression of G4-regulated genes in human cells. To expand the library of metallohelical structures that can act as efficient DNA G4 binders and downregulate genes containing G4-forming sequences in their promoter regions, we investigated the interaction of the two enantiomeric pairs of asymmetric Fe(II) triplex metallohelices with a series of five different DNA G4s formed by the human telomeric sequence (hTelo) and in the promoter regions of c-MYC, c-KIT, and k-RAS oncogenes. The metallohelices display preferential binding to G4s over duplex DNA in all investigated G4-forming sequences and induced arrest of DNA polymerase on template strands containing G4-forming sequences. Moreover, the investigated metallohelices suppressed the expression of c-MYC and k-RAS genes at mRNA and protein levels in HCT116 human cancer cells, as revealed by RT-qPCR analysis and western blotting.

• Klíčová slova
• DNA synthesis, G-quadruplexes, Metallohelices, expression of oncogenes, telomeres,
• MeSH
• DNA chemie   MeSH
• G-kvadruplexy * MeSH
• lidé MeSH
• nádory * MeSH
• onkogeny MeSH
• promotorové oblasti (genetika) MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DNA MeSH

DNA three-way junctions (3WJ) represent one of the simplest supramolecular DNA structures arising as intermediates in homologous recombination in the absence of replication. They are also formed transiently during DNA replication. Here we examine the ability of Fe(II)-based metallohelices to act as DNA 3WJ binders and induce DNA damage in cells. We investigated the interaction of eight pairs of enantiomerically pure Fe(II) metallohelices with four different DNA junctions using biophysical and molecular biology methods. The results show that the metallohelices stabilize all types of tested DNA junctions, with the highest selectivity for the Y-shaped 3WJ and minimal selectivity for the 4WJ. The potential of the best stabilizer of DNA junctions and, at the same time, the most selective 3WJ binder investigated in this work to induce DNA damage was determined in human colon cancer HCT116 cells. These metallohelices proved to be efficient in killing cancer cells and triggering DNA damage that could yield therapeutic benefits.

• MeSH
• DNA * chemie   MeSH
• konformace nukleové kyseliny MeSH
• lidé MeSH
• nádory * genetika   MeSH
• poškození DNA MeSH
• železnaté sloučeniny MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA * MeSH
• železnaté sloučeniny MeSH

The design of efficient and safe gene delivery vehicles remains a major challenge for the application of gene therapy. Of the many reported gene delivery systems, metal complexes with high affinity for nucleic acids are emerging as an attractive option. We have discovered that certain metallohelices-optically pure, self-assembling triple-stranded arrays of fully encapsulated Fe-act as nonviral DNA delivery vectors capable of mediating efficient gene transfection. They induce formation of globular DNA particles which protect the DNA from degradation by various restriction endonucleases, are of suitable size and electrostatic potential for efficient membrane transport and are successfully processed by cells. The activity is highly structure-dependent-compact and shorter metallohelix enantiomers are far less efficient than less compact and longer enantiomers.

• MeSH
• buněčné linie MeSH
• DNA chemie   ultrastruktura   MeSH
• exprese genu MeSH
• fluorescenční protilátková technika MeSH
• genetické vektory * chemie   ultrastruktura   MeSH
• kationty chemie   MeSH
• kovové nanočástice chemie   ultrastruktura   MeSH
• lidé MeSH
• mikroskopie atomárních sil metody   MeSH
• molekulární struktura MeSH
• průtoková cytometrie MeSH
• reportérové geny MeSH
• technika přenosu genů * MeSH
• transfekce MeSH
• viabilita buněk MeSH
• železnaté sloučeniny chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• kationty MeSH
• železnaté sloučeniny MeSH