title: Immunohistochemical expression of alpha-smooth muscle actin and glucocorticoid and calcitonin receptors in central giant-cell lesions.
abstract: BACKGROUND
  Central giant-cell lesions (CGCLs) are reactive lesions that consist histologically of spindle-shaped stromal cells, (fibroblasts and myofibroblasts) loosely arranged in a fibrous stroma, multinucleated giant cells and mononuclear cells with haemorrhagic areas. This study identified the immunoexpression of alpha-smooth muscle actin in spindle-shaped stromal cells, and glucocorticoid and calcitonin receptors in multinucleated giant cells and mononuclear cells. Their association with the clinical and radiographic characteristics of these lesions was identified.
  
  
  METHODS
  Thirty-five cases of CGCLs were studied. Expression of alpha-smooth muscle actin, glucocorticoid and calcitonin was evaluated by immunohistochemistry. The labelling index was 100 times the quotient of the number of positive cells divided by the total number of cells of each type. Logistic regression analysis was applied.
  
  
  RESULTS
  Alpha-smooth muscle actin was positive (54%) for spindle stromal cells (myofibroblasts). A significant association was observed with root resorption (P = 0.004) and cortical bone destruction (P = 0.024). Glucocorticoid immunoexpression was positive for 99% of the giant cells and 86.7% of the mononuclear cells. Glucocorticoid immunoexpression in the mononuclear cells was associated with root resorption (P = 0.031). A longer evolution time was associated with lower immunoexpression of glucocorticoid (OR 12.4: P = 0.047). Calcitonin immunoexpression was positive in 86% of the giant cells. Immunoexpression of calcitonin was associated with age (P = 0.040).
  
  
  CONCLUSIONS
  Myofibroblasts are important components of CGCLs, stromal cells and alpha-smooth muscle. Actin immunoexpression was associated with root and cortical bone resorption.
authors.affiliation: Department of Health Care, Universidad Autónoma Metropolitana, Xochimilco, México City, México.
authors.forename: Nancy Noya
authors.initials: NN
authors.lastname: Maiz
authors.affiliation: Department of Health Care, Universidad Autónoma Metropolitana, Xochimilco, México City, México.
authors.forename: Estela
authors.initials: E
authors.lastname: de la Rosa-García
authors.affiliation: Department of Health Care, Universidad Autónoma Metropolitana, Xochimilco, México City, México.
authors.forename: María Esther Irigoyen
authors.initials: ME
authors.lastname: Camacho
mesh_terms: D000199:Actins / Q000096:biosynthesis*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001862:Bone Resorption / Q000473:pathology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006101:Granuloma, Giant Cell / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008336:Mandibular Diseases / Q000378:metabolism* / Q000473:pathology; D008439:Maxillary Diseases / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D058628:Myofibroblasts / Q000378:metabolism / Q000473:pathology; D018003:Receptors, Calcitonin / Q000096:biosynthesis*; D011965:Receptors, Glucocorticoid / Q000096:biosynthesis*; D017154:Stromal Cells / Q000378:metabolism / Q000473:pathology; D055815:Young Adult
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D018003:Receptors, Calcitonin; D011965:Receptors, Glucocorticoid
keywords: alpha-smooth muscle actin; calcitonin; central giant-cell lesions; glucocorticoids