title: Activation of tumor suppressor p53 gene expression by magnetic thymine-imprinted chitosan nanoparticles.
abstract: Chitosan is a natural biodegradable polysaccharide that has been used to enhance gene delivery, owing to the ease with which chitosan nanoparticles enter the nucleus of cells. To study the effects of nuclear delivery of telomeric gene sequences, which contain thymine, we formed magnetic thymine-imprinted chitosan nanoparticles (TIPs) by the precipitation of chitosan, mixed with thymine and magnetic nanoparticles (to aid in separations). The mean size of the TIPS was 116 ± 18 nm; the dissociation constant for thymine was 21.8 mg mL(-1). We then treated human hepatocellular carcinoma (HepG2) with TIPs nanoparticles bearing bound thymine or a bound telomeric DNA sequence. The expression of the tumor suppressor p53 gene increased when TIPs were applied and decreased when telomere-bound TIPs were applied.
authors.affiliation: Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan.
authors.forename: Mei-Hwa
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, USA.
authors.forename: James L
authors.initials: JL
authors.lastname: Thomas
authors.affiliation: Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 81148, Taiwan. linhy@ntu.edu.tw.
authors.forename: Jian-Zhou
authors.initials: JZ
authors.lastname: Chen
authors.affiliation: Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
authors.forename: Jeng-Shiung
authors.initials: JS
authors.lastname: Jan
authors.affiliation: Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 81148, Taiwan. linhy@ntu.edu.tw.
authors.forename: Hung-Yin
authors.initials: HY
authors.lastname: Lin
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D048271:Chitosan / Q000737:chemistry*; D018014:Gene Transfer Techniques; D016158:Genes, p53; D056945:Hep G2 Cells / Q000737:chemistry* / Q000473:pathology; D006801:Humans; D008113:Liver Neoplasms / Q000737:chemistry* / Q000473:pathology; D053758:Nanoparticles / Q000737:chemistry*; D013941:Thymine / Q000737:chemistry*; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism
chemical_list: D016159:Tumor Suppressor Protein p53; D048271:Chitosan; D013941:Thymine