Cell Membrane and Intracellular Expression of Toll-Like Receptor 9 (Tlr9) in Colorectal Cancer and Breast Cancer Cell-Lines Publisher Pubmed



Shahriari S¹ ; Rezaeifard S² ; Moghimi HR³ ; Khorramizadeh MR^{1, 4} ; Faghih Z²
Source: Cancer Biomarkers Published:2017

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. © 2017 - IOS Press and the authors. All rights reserved.