title: Inhibitory effects of β-cyclodextrin-helenalin complexes on H-TERT gene expression in the T47D breast cancer cell line - results of real time quantitative PCR.
abstract: BACKGROUND
  Nowadays, the encapsulation of cytotoxic chemotherapeutic agents is attracting interest as a method for drug delivery. We hypothesized that the efficiency of helenalin might be maximized by encapsulation in β-cyclodextrin nanoparticles. Helenalin, with a hydrophobic structure obtained from flowers of Arnica chamissonis and Arnica Montana, has anti-cancer and anti-inflammatory activity but low water solubility and bioavailability. β-Cyclodextrin (β-CD) is a cyclic oligosaccharide comprising seven D-glucopyranoside units, linked through 1,4-glycosidic bonds.
  
  
  METHODS
  To test our hypothesis, we prepared β-cyclodextrin- helenalin complexes to determine their inhibitory effects on telomerase gene expression by real-time polymerase chain reaction (q-PCR) and cytotoxic effects by colorimetric cell viability (MTT) assay.
  
  
  RESULTS
  MTT assay showed that not only β-cyclodextrin has no cytotoxic effect on its own but also it demonstrated that β-cyclodextrin- helenalin complexes inhibited the growth of the T47D breast cancer cell line in a time and dose-dependent manner. Our q-PCR results showed that the expression of telomerase gene was effectively reduced as the concentration of β-cyclodextrin-helenalin complexes increased.
  
  
  CONCLUSIONS
  β-Cyclodextrin-helenalin complexes exerted cytotoxic effects on T47D cells through down-regulation of telomerase expression and by enhancing Helenalin uptake by cells. Therefore, β-cyclodextrin could be superior carrier for this kind of hydrophobic agent.
authors.affiliation: Drug Applied Research Center, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran E-mail : Rahmati_bio@yahoo.com, Akbarzadehab@tbzmed.ac.ir, Zarghami@tbzmed.ac.ir.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Ghasemali
authors.forename: Kazem
authors.initials: K
authors.lastname: Nejati-Koshki
authors.forename: Elham
authors.initials: E
authors.lastname: Tafsiri
authors.forename: Mohamad
authors.initials: M
authors.lastname: Rahmati-Yamchi
authors.forename: Abolfazl
authors.initials: A
authors.lastname: Akbarzadeh
authors.forename: Effat
authors.initials: E
authors.lastname: Alizadeh
authors.forename: Mozhgan
authors.initials: M
authors.lastname: Abbasi
authors.forename: Amin
authors.initials: A
authors.lastname: Barkhordari
authors.forename: Majid
authors.initials: M
authors.lastname: Tozihi
authors.forename: Shirafkan
authors.initials: S
authors.lastname: Kordi
authors.forename: Nosratollah
authors.initials: N
authors.lastname: Zarghami
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects*; D005260:Female; D006801:Humans; D053758:Nanoparticles / Q000008:administration & dosage; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D064449:Sequestering Agents / Q000737:chemistry / Q000378:metabolism; D012717:Sesquiterpenes / Q000494:pharmacology*; D045789:Sesquiterpenes, Guaiane; D017550:Spectroscopy, Fourier Transform Infrared; D019098:Telomerase / Q000037:antagonists & inhibitors* / Q000235:genetics; D014407:Tumor Cells, Cultured; D047392:beta-Cyclodextrins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D012333:RNA, Messenger; D064449:Sequestering Agents; D012717:Sesquiterpenes; D045789:Sesquiterpenes, Guaiane; D047392:beta-Cyclodextrins; C001329:helenalin; C509186:TERT protein, human; D019098:Telomerase; C031215:betadex