title: Gap junctions: the claymore for cancerous cells.
abstract: BACKGROUND
  Gap junctions play an important role in the cell proliferation in mammalian cells as well as carcinogenesis. However, there are controversial issues about their role in cancer pathogenesis. This study was designed to evaluate genotoxicity and cytotoxicity of Carbenoxolone (CBX) as a prototype of inter-cellular gap junction blocker in MCF7 and BT20 human breast cancer cells.
  
  
  METHODS
  The MCF7and BT20 human breast cancer cell lines were cultivated, and treated at designated confluency with different doses of CBX. Cellular cytotoxicity was examined using standard colorimetric assay associated with cell viability tests. Gene expression evaluation was carried out using real time polymerase chain reaction (PCR).
  
  
  RESULTS
  MCF7 and BT20 cells were significantly affected by CBX in a dose dependent manner in cell viability assays. Despite varying expression of genes, down regulation of pro- and anti-apoptotic genes was observed in these cells.
  
  
  CONCLUSIONS
  Based upon this investigation, it can be concluded that CBX could affect both low and high proliferative types of breast cancer cell lines and disproportionate down regulation of both pre- and anti-apoptotic genes may be related to interacting biomolecules, perhaps via gap junctions.
authors.affiliation: Department of Pharmacology and Toxicology, School of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran ; Research Center for Pharmaceutical Nanotechnology, School of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran ; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Asadi-Khiavi
authors.forename: Hossein
authors.initials: H
authors.lastname: Hamzeiy
authors.forename: Sajjad
authors.initials: S
authors.lastname: Khani
authors.forename: Ailar
authors.initials: A
authors.lastname: Nakhlband
authors.forename: Jaleh
authors.initials: J
authors.lastname: Barar
keywords: Cancer Cells; Cytotoxicity; EGFR; Gap Junction; Gene Expression