title: Based on Molecular Profiling of Gene Expression, Palmoplantar Pustulosis and Palmoplantar Pustular Psoriasis Are Highly Related Diseases that Appear to Be Distinct from Psoriasis Vulgaris.
abstract: There is a controversy surrounding the existence of palmoplantar pustulosis (PPP) and palmoplantar pustular psoriasis (PPPP) as separate clinical entities or as variants of the same clinical entity. We used gene expression microarray to compare gene expression in PPP and PPPP.
  
  
  
  Skin biopsies from subjects with PPP (3), PPPP (6), psoriasis vulgaris (10) and acral skin from normal subjects (7) were analyzed using gene expression microarray. Principal component analysis showed that PPP and PPPP were different from psoriasis vulgaris and normal acral skin. However gene expression of PPP and PPPP clustered together and could not be used to differentiate PPP from PPPP. Gene-wise comparison between PPP and PPPP found no gene to be differentially expressed at a false discovery rate lower than 0.05. Surprisingly we found a higher expression of several genes involved in neural pathways (e.g. GPRIN and ADAM23) in PPP/PPPP as compared to psoriasis vulgaris and normal acral skin. Immunohistochemistry confirmed those findings and showed a keratinocyte localization for those proteins.
  
  
  
  PPP and PPPP could not be differentiated using gene expression microarray suggesting that they are not distinct clinical entities. Increased expression of GPRIN1, and ADAM23 in keratinocytes suggests that these proteins could be new therapeutic targets for PPP/PPPP.
authors.affiliation: Innovaderm Research, Montreal, Quebec, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Bissonnette
authors.affiliation: Laboratory of Investigative Dermatology, Rockefeller University, New York, New York, United States of America.
authors.forename: Mayte
authors.initials: M
authors.lastname: Suárez-Fariñas
authors.affiliation: Laboratory of Investigative Dermatology, Rockefeller University, New York, New York, United States of America.
authors.forename: Xuan
authors.initials: X
authors.lastname: Li
authors.affiliation: Laboratory of Investigative Dermatology, Rockefeller University, New York, New York, United States of America.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Bonifacio
authors.affiliation: Janssen Research & Development, LLC, Spring House, Pennsylvania, United States of America.
authors.forename: Carrie
authors.initials: C
authors.lastname: Brodmerkel
authors.affiliation: Laboratory of Investigative Dermatology, Rockefeller University, New York, New York, United States of America.
authors.forename: Judilyn
authors.initials: J
authors.lastname: Fuentes-Duculan
authors.affiliation: Laboratory of Investigative Dermatology, Rockefeller University, New York, New York, United States of America.
authors.forename: James G
authors.initials: JG
authors.lastname: Krueger
mesh_terms: D020869:Gene Expression Profiling; D006801:Humans; D011565:Psoriasis / Q000235:genetics*