title: Cell membrane and intracellular expression of toll-like receptor 9 (TLR9) in colorectal cancer and breast cancer cell-lines.
abstract: BACKGROUND
  Toll-like receptor 9 (TLR9) is a DNA receptor of innate immune system which plays a pivotal role in inflammatory response. Recent evidence reveals over-expression and functionality of TLR9 in a wide variety of cancer cells and its contribution to tumor cell proliferation and survival.
  
  
  OBJECTIVE
  In this study, we assessed the aberrant cell surface expression of TLR9 in cancer using cell-lines model.
  
  
  METHODS
  Three breast cancer cell-lines (MDA-MB-231, MCF7 and SKBR3) and five colorectal adenocarcinoma cell-lines (HT29, HT29/219, SW480, SW48 and SW1116) in addition to one primary foreskin isolated fibroblast cell were analyzed for cell surface and intracellular expression of TLR9 by flow cytometry method.
  
  
  RESULTS
  Maximum surface expression of TLR9 was observed in colorectal cell-line HT29/219 (38.35%), as compared with the bottom line fibroblast normal cells (0.12%). The most intracellular expression was observed in MCF-7 cells (35.63%), whereas MDA-MB-231 expressed the maximum surface/intra cellular expression (277 times).
  
  
  CONCLUSIONS
  Based on the results, we hypothesize that aberrant surface expression of TLR9 on tumor cells may promote tumor growth and invasion. It might also highlight a dual contradictory role for CpG-ODNs, as adjutant in cancer therapy.
authors.affiliation: Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shadab
authors.initials: S
authors.lastname: Shahriari
authors.affiliation: Cancer Immunology Group, Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Somayeh
authors.initials: S
authors.lastname: Rezaeifard
authors.affiliation: School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Moghimi
authors.affiliation: Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.|Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, EMRI, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Khorramizadeh
authors.affiliation: Cancer Immunology Group, Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Faghih
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D002462:Cell Membrane / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D019073:HT29 Cells; D006801:Humans; D061986:MCF-7 Cells; D009838:Oligodeoxyribonucleotides / Q000008:administration & dosage; D051217:Toll-Like Receptor 9 / Q000235:genetics*
chemical_list: D014408:Biomarkers, Tumor; C408982:CPG-oligonucleotide; D009838:Oligodeoxyribonucleotides; C495371:TLR9 protein, human; D051217:Toll-Like Receptor 9
keywords: TLR9; breast cancer; colon cancer