@article {https://doi.org/10.1002/elps.202100077,
	title = {Quantitative characterization of human oncogene promoter G-quadruplex DNA-ligand interactions using a combination of mass spectrometry and capillary electrophoresis},
	journal = {ELECTROPHORESIS},
	volume = {42},
	number = {n/a},
	year = {2021},
	month = {05/2021},
	pages = {1450-1460},
	type = {Research},
	chapter = {1450},
	abstract = {<p>Abstract Human c-KIT oncogene is known to regulate cell growth and proliferation, and thus, acts as a probable target in the treatment of gastrointestinal tumors (GIST). To identify small molecule ligands which can specifically bind with the G-quadruplex (G4) in the c-KIT promoter region as potential antitumor agents, we propose the combination of electrospray ionization\&ndash;mass spectrometry (ESI-MS), capillary electrophoresis frontal analysis (CE-FA), and Taylor dispersion analysis (TDA) to accurately investigate the G4/ligands binding properties. First, ESI\&ndash;MS was used for initial screening of natural products (NPs). CE-FA was then used to calculate specific binding constants and the stoichiometry of the native state binding pair in solution. Next, TDA, a micro-capillary flow technique was used to examine the effect of the ligand binding on the diffusivity and particle size of the c-KIT G4. Two of the screened NPs, scopolamine butylbromide (L1) and isorhamnetin-3-O-neohesperidoside (L3), were found to specifically bind to the c-KIT G4 with binding constants of around 104 M\&ndash;1 and 1:1 stoichiometry in a free solution. TDA data showed that ligand binding (both L1 and L3) induced the c-KIT strands to fold into a tightly structured G4 with a decreased hydrodynamic radius. These ligands have the potential to be drug candidates for the regulation of c-KIT gene transcription by stabilizing the G4 structure. This methodology not only increased the speed of analysis but also improved its accuracy and specificity compared with the conventional binding approaches.</p>},
	keywords = {binding constant, c-KIT oncogene, Capillary electrophoresis frontal analysis, Electrospray ionization{\textendash}mass spectrometry, G-quadruplex, Taylor dispersion analysis},
	doi = {https://doi.org/10.1002/elps.202100077},
	url = {https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/abs/10.1002/elps.202100077},
	author = {Wang, Shuangshuang and Yang, Yang and Yang, Yunhe and Li, Huihui and Chen, David D.Y.}
}
