title: Apoptosis and apoptotic pathway in actinic prurigo by immunohistochemistry.
abstract: BACKGROUND
  Actinic prurigo (AP) is an idiopathic photodermatosis, this entity requires exposure to UV-B and -A to develop lesions. Apoptosis is a physiological death program that can be initiated by a permanently active mechanism (extrinsic pathway) or irreparable damage (intrinsic pathway).
  
  
  METHODS
  Descriptive study, the sample size comprised 64 paraffin blocks of tissue with a diagnosis of AP. In H&E-stained slides, the diagnosis of AP was corroborated, and 1-µm-thick sections were processed for immunohistochemistry (IHC). A database was constructed with SPSS version 20, Inc., Chicago, IL, USA, and descriptive statistics were analyzed by X2 test and comparison of means.
  
  
  RESULTS
  A total of 64 cases were processed, of which 40 (62.5%) were cheilitis AP and 24 (37.5%) were AP in the skin. Of the 40 cheilitis samples, 27 were positive for Bcl-2 and caspase 3 (67.5%), p53 was expressed in 30 (75%). Of the skin lesions, p53 and caspase 3 were expressed in 18 of 24 cases (75%), and 13 were positive for Bcl-2 (54%).
  
  
  CONCLUSIONS
  We propose that apoptosis is the last step in the type IV subtype a-b hypersensitivity response-activation of the intrinsic pathway indicates that external factors, such as UV-A and -B are the trigger.
authors.affiliation: Department of Dermatology, Dr. Manuel Gea González General Hospital, Calzada de Tlalpan 4800, Sección XVI Delegación Tlalpan, México, D.F. C.P 14080, elisavega50@gmail.com.
authors.forename: Juan-Carlos
authors.initials: JC
authors.lastname: Cuevas-González
authors.forename: María-Elisa
authors.initials: ME
authors.lastname: Vega-Memíje
authors.forename: Francisco-Javier
authors.initials: FJ
authors.lastname: García-Vázquez
authors.forename: Erika
authors.initials: E
authors.lastname: Rodríguez-Lobato
authors.forename: José-Eduardo
authors.initials: JE
authors.lastname: Farfán-Morales
mesh_terms: D017209:Apoptosis; D006801:Humans; D007150:Immunohistochemistry; D010787:Photosensitivity Disorders / Q000473:pathology*; D012873:Skin Diseases, Genetic / Q000473:pathology*