title: Phenotypic and Functional Characterization of Ductal Carcinoma In Situ-Associated Myoepithelial Cells.
abstract: BACKGROUND
  Ductal carcinoma in situ (DCIS) is contained by myoepithelial cells that are morphologically similar to normal breast tissue myoepithelial cells. However, phenotypic and functional characteristics of DCIS-associated myoepithelial cells are not known. In this study, we aimed to assess the characteristics of DCIS-associated myoepithelial cells.
  
  
  METHODS
  Immunophenotypic and functional characteristics of myoepithelial cells of pure DCIS, the DCIS component of infiltrating duct carcinoma (IDC), and the adjacent normal breast tissue of both groups (30 cases in each group) was assessed using phenotypic (CK5/6, CK14, p63, and calponin) and functional markers (maspin and CXCL14).
  
  
  RESULTS
  There was a decrease in expression of CK14, p63, and calponin in pure DCIS-associated myoepithelial cells compared with normal breast tissue myoepithelial cells (43.3% vs. 80.3%, 3.3% vs. 70%, 46.6 vs. 93.3%, respectively) and in the DCIS component of IDC compared with normal breast tissue myoepithelial cells (56.6% vs. 100%, 3.3% vs. 73.3%, 56.6% vs. 96.6%, respectively). CK5/6 expression was low to absent in myoepithelial cells of pure DCIS and the DCIS component of IDC as well as normal breast tissue myoepithelial cells. Maspin was expressed in all samples of normal breast tissue; however, 20% of pure DCIS and 26.6% of the DCIS component of IDC showed decreased expression. CXCL14 expression was greater in pure DCIS compared with adjacent normal breast tissue and the DCIS component of IDC.
  
  
  CONCLUSIONS
  Decreased expression of myoepithelial cell markers in DCIS suggests that DCIS-associated myoepithelial cells are phenotypically different from their normal counterparts. Two or more markers, preferably p63 and calponin, should be used to distinguish in situ from invasive breast carcinomas.
authors.affiliation: Department of Histopathology, Post Graduate Institute of Medical Education & Research (PGIMER), Sector 12, Chandigarh 60012, India.
authors.forename: Manish
authors.initials: M
authors.lastname: Rohilla
authors.affiliation: Department of Histopathology, Post Graduate Institute of Medical Education & Research (PGIMER), Sector 12, Chandigarh 60012, India. Electronic address: docaman5@hotmail.com.
authors.forename: Amanjit
authors.initials: A
authors.lastname: Bal
authors.affiliation: Department of General Surgery, Post Graduate Institute of Medical Education & Research (PGIMER), Sector 12, Chandigarh 60012, India.
authors.forename: Gurpreet
authors.initials: G
authors.lastname: Singh
authors.affiliation: Department of Histopathology, Post Graduate Institute of Medical Education & Research (PGIMER), Sector 12, Chandigarh 60012, India.
authors.forename: Kusum
authors.initials: K
authors.lastname: Joshi
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000737:chemistry* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000737:chemistry* / Q000473:pathology; D004847:Epithelial Cells / Q000737:chemistry* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D053555:Keratin-5 / Q000032:analysis; D053553:Keratin-6 / Q000032:analysis; D014157:Transcription Factors / Q000032:analysis; D025521:Tumor Suppressor Proteins / Q000032:analysis
chemical_list: D014408:Biomarkers, Tumor; D053555:Keratin-5; D053553:Keratin-6; C115051:TP63 protein, human; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins
keywords: CXCL14; DCIS; Immunohistochemistry; Maspin; Myoepithelial cells