Controversial roles played by toll like receptor 4 in urinary bladder cancer; A systematic review

Abstract

Introduction: Urinary bladder cancer (UBC) is a prevalent human cancer. The main mechanisms which lead to eradication or progression the disease has yet to be clarified. Toll like receptor (TLR) 4 is a membrane receptor which is expressed either on immune cells or tumor cells. This review article was aimed to clear the main mechanisms played by TLR4 and its related intracellular pathways on outcome of UBC.

Method: PubMed, Scopus and Google scholar databases have been used for searching related research articles which have evaluated the roles played by TLR4 and its related intracellular pathways on outcome of UBC.

Results: Collected information from the related articles revealed that TLR4 either participates in induction of immune responses against UBC or development of the malignancy. There are limited investigations regarding the genetic variations of TLR4 in UBC.

Discussion: According to the results it seems that TLR4/ligands interaction outcome is dependent on several factors including TLR4 ligand doses, interaction of TLR4 with its ligands on immune cells or tumor cells, and other TLRs/ligand interaction simultaneously.

Keywords: Bladder cancer; MYD88; TLR4; TRIF.