title: The role of tumor necrosis factor-alpha (TNF-alpha) in bone resorption present in middle ear cholesteatoma.
abstract: Cholesteatoma may cause bone erosion, with high morbidity and mortality rates. Tumor necrosis factor-alpha (TNF-a) is one of the main cytokines involved in this process. Our goal was to evaluate the role of TNF-a in Bone Resorption and its effect on cholesteatoma.
  
  
  METHODS
  analysis and critical literature review.
  
  
  RESULTS
  Different studies have demonstrated that TNF-a is capable of causing bone erosion. It may stimulate the differentiation and maturation of osteoclasts or it may act on the bone matrix, exposing it to the action of the osteoclasts. It is possible to inhibit TNF-a, reducing its effects and prevent bone loss in illnesses such as rheumatoid arthritis,and there has been no specific investigation regarding cholesteatomas. All studies agree on the importance of TNF-a in the bone resorption process present in cholesteatomas, and on the degree of destruction observed; however, there is no consensus as to its location. These differences are probably due to receptor site.
  
  
  CONCLUSIONS
  TNF-a, present in cholesteatomas, promotes bone resorption, along with other cytokines (RANKL and IL-1) related to complications.
authors.affiliation: Otorhinus Clinic and Hospital Santa Marcelina, Brazil.
authors.forename: Rodrigo Faller
authors.initials: RF
authors.lastname: Vitale
authors.forename: Fernando de Andrade Quintanilha
authors.initials: Fde A
authors.lastname: Ribeiro
mesh_terms: D001862:Bone Resorption / Q000378:metabolism* / Q000473:pathology; D018424:Cholesteatoma, Middle Ear / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: D014409:Tumor Necrosis Factor-alpha