title: Carbonate apatite-facilitated intracellularly delivered siRNA for efficient knockdown of functional genes.
abstract: Gene therapy through intracellular delivery of a functional gene or a gene-silencing element is a promising approach to treat critical diseases. Elucidation of the genetic basis of human diseases with complete sequencing of human genome revealed many vital genes as possible targets in gene therapy programs. RNA interference (RNAi), a powerful tool in functional genomics to selectively silence messenger RNA (mRNA) expression, can be harnessed to rapidly develop novel drugs against any disease target. The ability of synthetic small interfering RNA (siRNA) to effectively silence genes in vitro and in vivo, has made them particularly well suited as a drug therapeutic. However, since naked siRNA is unable to passively diffuse through cellular membranes, delivery of siRNA remains the major hurdle to fully exploit the potential of siRNA technology. Here pH-sensitive carbonate apatite has been developed to efficiently deliver siRNA into the mammalian cells by virtue of its high affinity interactions with the siRNA and the desirable size of the resulting siRNA/apatite complex for effective cellular endocytosis. Moreover, following internalization by cells, siRNA was found to be escaped from the endosomes in a time-dependent manner and finally, more efficiently silenced reporter genes at a low dose than commercially available lipofectamine. Knockdown of cyclin B1 gene with only 10nM of siRNA delivered by carbonate apatite resulted in the significant death of cancer cells, suggesting that the new method of siRNA delivery is highly promising for pre-clinical and clinical cancer therapy.
authors.affiliation: Department of Biomolecular Engineering, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
authors.forename: Sharif
authors.initials: S
authors.lastname: Hossain
authors.forename: Anthony
authors.initials: A
authors.lastname: Stanislaus
authors.forename: Ming Jang
authors.initials: MJ
authors.lastname: Chua
authors.forename: Seiichi
authors.initials: S
authors.lastname: Tada
authors.forename: Yoh-ichi
authors.initials: Y
authors.lastname: Tagawa
authors.forename: Ezharul Hoque
authors.initials: EH
authors.lastname: Chowdhury
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Akaike
mesh_terms: D001031:Apatites / Q000737:chemistry*; D002470:Cell Survival / Q000235:genetics; D003001:Cloning, Molecular; D003587:Cytomegalovirus / Q000235:genetics; D004337:Drug Carriers / Q000737:chemistry*; D004339:Drug Compounding; D055785:Gene Knockdown Techniques / Q000379:methods*; D020868:Gene Silencing; D005822:Genetic Vectors / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D010316:Particle Size; D010957:Plasmids; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000235:genetics; D012995:Solubility; D013499:Surface Properties
chemical_list: D001031:Apatites; D004337:Drug Carriers; D034741:RNA, Small Interfering; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; C030782:carboapatite