title: Psoriasis and melanocytic naevi: does the first confer a protective role against melanocyte progression to naevi?
abstract: BACKGROUND
  Some of the cytokines that have effects on melanogenesis are also reported to be involved in psoriasis.
  
  
  OBJECTIVE
  We therefore studied the relationship between psoriasis and melanocytic naevi. In particular, the aim of our study was to investigate the number of melanocytic naevi in patients with psoriasis vs. controls.
  
  
  METHODS
  We performed a prospective case-control study, analysing 93 adult patients with psoriasis and 174 adult aged-matched controls. For each participant a questionnaire was completed to establish personal data, personal medical history, and personal and familial history of skin cancer and psoriasis. We analysed interleukin (IL)-1α, IL-6 and tumour necrosis factor (TNF)-α gene expression at the peripheral blood mononuclear cell level in patients with psoriasis and in controls.
  
  
  RESULTS
  In our study, patients with psoriasis presented a lower number of areas with naevi in comparison with controls (P < 0·0001). Nobody had ever had squamous cell carcinoma or melanoma in the psoriatic group; moreover, there was a significant difference in familial history of melanoma between the two groups (none in the psoriatic group vs. 8% in the control group; P < 0·05). IL-1α, IL-6 and TNF-α expression levels were higher in patients with psoriasis.
  
  
  CONCLUSIONS
  People with psoriasis had fewer melanocytic naevi. This suggests that the proinflammatory cytokine network in psoriasis skin might inhibit melanogenesis, melanocyte growth and/or progression to naevi.
authors.affiliation: Sezione di Dermatologia Clinica, Allergologica e Venereologica, Dipartimento di Patologia Sistematica, Università di Napoli Federico II, 80131 Naples, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Balato
authors.forename: L
authors.initials: L
authors.lastname: Di Costanzo
authors.forename: A
authors.initials: A
authors.lastname: Balato
authors.forename: C
authors.initials: C
authors.lastname: Patruno
authors.forename: M
authors.initials: M
authors.lastname: Scalvenzi
authors.forename: F
authors.initials: F
authors.lastname: Ayala
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D053582:Interleukin-1alpha / Q000235:genetics / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009508:Nevus, Pigmented / Q000150:complications* / Q000151:congenital / Q000235:genetics / Q000473:pathology; D010375:Pedigree; D010641:Phenotype; D011446:Prospective Studies; D011565:Psoriasis / Q000150:complications* / Q000235:genetics / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D055815:Young Adult
chemical_list: D053582:Interleukin-1alpha; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha