title: Decrease in serine protease HtrA1 expression correlates with grade and recurrence in meningiomas.
abstract: OBJECTIVE
  HtrA1 is a serine protease which was shown to be down-regulated in a variety of human cancers. It is considered to be a tumor suppressor and suggested as a prognostic marker and a therapeutic candidate. In order to investigate any possible implication of HtrA1 in meningioma we studied 100 cases.
  
  
  METHODS
  We used immunohistochemistry to determine HtrA1 expression in tumor tissue. Expression levels were evaluated with respect to tumor grade and recurrence.
  
  
  RESULTS
  Our data revealed a strong association between decrease in HtrA1 expression and increase in meningioma grade (p=0.005). Most importantly, patients with higher HtrA1 expression had a lower rate of recurrence (p<0.001).
  
  
  CONCLUSIONS
  According to our results HtrA1 appeared as an immunohistochemical marker to predict behaviour of the meningioma, mainly the recurrence. Although the exact mechanisms of HtrA1 are still largely unknown, we think that further in vivo and in vitro studies explaining the molecular targets of HtrA1 would have a great importance with regard to its role as a therapeutic agent for meningioma.
authors: Department of Pathology, Ministry of Health, Diskapi Yildirim Beyazit Education and Research Hospital, Ankara, Turkey. Electronic address: evrimin@yahoo.com.
authors: Evrim
authors: E
authors: Önder
authors: Department of Pathology, Ministry of Health, Diskapi Yildirim Beyazit Education and Research Hospital, Ankara, Turkey.
authors: Ata Türker
authors: AT
authors: Arıkök
authors: Department of Neurosurgery, Ministry of Health, Diskapi Yildirim Beyazit Education and Research Hospital, Ankara, Turkey.
authors: Hakan
authors: H
authors: Seçkin
authors: Department of Pathology, Ministry of Health, Diskapi Yildirim Beyazit Education and Research Hospital, Ankara, Turkey.
authors: Murat
authors: M
authors: Alper
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D005260:Female; D000074289:High-Temperature Requirement A Serine Peptidase 1; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D008577:Meningeal Neoplasms / Q000378:metabolism* / Q000473:pathology*; D008579:Meningioma / Q000378:metabolism* / Q000473:pathology*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000473:pathology*; D011379:Prognosis; D012697:Serine Endopeptidases / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D000074289:High-Temperature Requirement A Serine Peptidase 1; C474012:HTRA1 protein, human; D012697:Serine Endopeptidases
keywords: Grade; HtrA1; Immunohistochemistry; Meningioma; Recurrence