title: Immunohistochemical evaluation of type IV collagen and laminin-332 γ2 chain expression in well-differentiated oral squamous cell carcinoma and oral verrucous carcinoma: a new recommended cut-off.
abstract: BACKGROUND
  Invasion and metastasis are two characteristics of malignant tumors, which perform by proteolytic destruction of the components of basement membrane (BM) and cell migration. The aim of this study was to evaluate the immunohistochemical (IHC) assessment of type IV collagen and laminin-332 γ2 (Ln-332 γ2) chain expression in well-differentiated oral squamous cell carcinoma (OSCC) and oral verrucous carcinoma (OVC), because these two lesions have same histopathologic findings whereas they have different biological behaviors.
  
  
  METHODS
  Destruction of BM and cell migration were evaluated by IHC in 15 cases of epithelial hyperplasia with no dysplasia (A group), 15 cases of OVC (B group) and 15 cases of well-differentiated OSCC (C group).
  
  
  RESULTS
  There was a significant difference in type IV collagen immunohistochemical staining between three groups, but there were no significant differences between B and C groups. Expression of Ln-332 γ2 chain was not detected in A group. Ln-332 γ2 chain labeling index had significantly difference between B and C groups. The number of Ln-332 γ2 chain immunostaining positive cells was less than 5% in B group and over than 5% in C group which there were significantly differences between these two groups.
  
  
  CONCLUSIONS
  Isolated immunohistochemical study of type IV collagen does not clearly define that a lesion is invasive or non-invasive and evaluation of Ln-332 γ2 chain expression (cut-off 5%) may be useful as a marker for description of biological differences and diagnosis of OVC from well-differentiated OSCC, especially in doubtful cases.
authors.affiliation: Dental Research Center, Department of Oral and Maxillofacial Pathology, Dental School, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Massoumeh
authors.initials: M
authors.lastname: Zargaran
authors.forename: Nosratollah
authors.initials: N
authors.lastname: Eshghyar
authors.forename: Pejman Bakianian
authors.initials: PB
authors.lastname: Vaziri
authors.forename: Hamed
authors.initials: H
authors.lastname: Mortazavi
mesh_terms: D000328:Adult; D000368:Aged; D001485:Basement Membrane / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D018289:Carcinoma, Verrucous / Q000378:metabolism* / Q000473:pathology; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000096:biosynthesis*; D002465:Cell Movement; D016009:Chi-Square Distribution; D024141:Collagen Type IV / Q000032:analysis / Q000096:biosynthesis*; D003937:Diagnosis, Differential; D004848:Epithelium / Q000473:pathology; D005260:Female; D006801:Humans; D006965:Hyperplasia; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000378:metabolism* / Q000473:pathology; D000097794:Kalinin
chemical_list: D015815:Cell Adhesion Molecules; D024141:Collagen Type IV; D000097794:Kalinin