Os genes TLR em doenças da cavidade oral

: uma revisão sistemática

Abstract

Introduction: TLR (Toll-like receptor) genes are part of the immune system and are present in cells as cytoplasmic or transmembrane proteins. To date, 10 different TLRs have been discovered in humans (TLR1-10). They are involved in ligand recognition and signal transduction. Several studies indicate that TLRs are involved in the development of oral cavity diseases. Objective: The purpose of this work was to identify the alterations of TLR genes associated with oral cavity diseases, with the aim of validating their use as a prognostic factor or biomarkers of these diseases. Methodology: The search was performed in PubMed, Web of Science, and Cochrane Library databases until January 2023. The selection of articles was performed by 2 researchers according to defined inclusion and exclusion criteria. Diseases were divided into groups according to the number of results obtained. Results: From a total of 452 articles, 93 duplicates and 1 with the wrong link were removed. By reading the title and/or abstract, 243 articles were excluded and from the full-text reading, where 115 articles were evaluated, 23 more were excluded according to the inclusion and exclusion criteria. There were 92 articles included in this study. The results were divided into 6 groups, according to the pathology: Oral Cancer (OC), Periodontal Disease (PD), Sjögren's Syndrome (SS), Oral Lichen Planus (OLP), Behçet's Disease (BD) and Other Diseases. The most studied TLRs were TLR2 and TLR4. TLR10 was the least addressed by the authors. TLR2 and TLR4 showed increased expression in patients with Periodontal Disease and Behcet's disease. TLR4 appears to be involved in the development of Oral cancer and Oral Lichen Planus.
Conclusion: More studies are needed to support the involvement of TLRs genes in oral cavity diseases. Despite this, some TLRs have been identified as a possible cause of progression of these diseases. It is concluded that TLRs may be used in the future as prognostic factors or biomarkers in these diseases.

Date of Award	26 Jul 2023
Original language	Portuguese
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Raquel Silva (Supervisor) & Maria José Correia (Co-Supervisor)