title: Osteopontin is not a specific marker in malignant pleural mesothelioma.
abstract: OBJECTIVE
  Osteopontin (OPN) is an integrin-binding protein recently shown to be related to tumorigenesis, progression and metastasis in different experimental models of malignancy. Malignant pleural mesothelioma (MPM) is a fatal disease in which the prognosis remains very poor and the knowledge of predictive factors for outcome is insufficient. The identification of new molecules involved in cancer initiation and development is a fundamental step for improving the curability of this kind of tumor. The purpose of this study is to define the role of OPN in the diagnosis of MPM by determining its prognostic and diagnostic value.
  
  
  METHODS
  A group of 24 surgically staged MPM subjects was compared with a group of 31 subjects with nonmalignant pulmonary diseases, and with 37 healthy controls. Tumor tissue was analyzed for OPN by immunohistochemical tests, and plasma OPN levels were measured by an enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Plasma OPN levels were not significantly higher in either of the patient groups compared with the control group. Immunohistochemical analysis revealed OPN staining of tumor cells in 21 of 24 MPMs. Receiver operating characteristic curve/area under the curve (ROC/AUC) analysis comparing the plasma OPN levels in the healthy group with those of MPM patients showed 40% sensitivity and 100% specificity at a cutoff value of 60.8 ng of OPN per milliliter (AUC 0.6).
  
  
  CONCLUSIONS
  Plasma OPN levels do not discriminate between chronic inflammatory and malignant lung diseases and staining intensity in MPM specimens does not correlate with OPN plasma levels.
authors.affiliation: Lung Cancer Unit, National Cancer Research Institute, Genoa, Italy. laura.paleari@istge.it
authors.forename: Laura
authors.initials: L
authors.lastname: Paleari
authors.forename: Nicola
authors.initials: N
authors.lastname: Rotolo
authors.forename: Andrea
authors.initials: A
authors.lastname: Imperatori
authors.forename: Roberto
authors.initials: R
authors.lastname: Puzone
authors.forename: Fausto
authors.initials: F
authors.lastname: Sessa
authors.forename: Francesca
authors.initials: F
authors.lastname: Franzi
authors.forename: Elisa
authors.initials: E
authors.lastname: Meacci
authors.forename: Pierpaolo
authors.initials: P
authors.lastname: Camplese
authors.forename: Alfredo
authors.initials: A
authors.lastname: Cesario
authors.forename: Michela
authors.initials: M
authors.lastname: Paganuzzi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D008297:Male; D008654:Mesothelioma / Q000175:diagnosis* / Q000378:metabolism*; D008875:Middle Aged; D009362:Neoplasm Metastasis; D053495:Osteopontin / Q000096:biosynthesis*; D010997:Pleural Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D053495:Osteopontin