title: MGMT immunoexpression in adamantinomatous craniopharyngiomas.
abstract: At present, no effective medical treatment exists for recurrent and aggressive craniopharyngiomas that are resistant to conventional therapies, including surgery and adjuvant radiotherapy. Temozolomide is an alkylating chemotherapeutic agent used routinely in the management of high grade gliomas. The response to temozolomide is suggested to be dependent on the tumoral expression of O-6 methylguanine DNA methyltransferase (MGMT). Evidence supports that low MGMT immunoexpression correlates with positive response to temozolomide. Therefore, we aimed to assess MGMT immunoexpression in adamantinomatous craniopharyngiomas, in an effort to predict the likelihood of response to temozolomide. The MGMT immunostaining was performed on 23 adamantinomatous craniofaryngiomas operated at the Sisli Etfal Training and Research Hospital and identified by histological analysis. Paraffin embedded tissue sections were immunostained for MGMT and were evaluated semi-quantitatively. Of the 23 cases evaluated, 22 (96%) demonstrated negative (<10%) and 1 (4%) demonstrated low (10%) MGMT immunoexpression. Data from this study suggest a high proportion of adamantinomatous craniopharyngiomas exhibit negative/low MGMT immunoreactivity and could be treated with temozolomide, if conventional therapy fails.
authors.affiliation: Endocrinology and Metabolism Clinic, Sisli Etfal Training and Research Hospital, Istanbul, Turkey. zuhur744@gmail.com
authors.forename: Sayid Shafi
authors.initials: SS
authors.lastname: Zuhur
authors.forename: Ahmet Murat
authors.initials: AM
authors.lastname: Müslüman
authors.forename: Canan
authors.initials: C
authors.lastname: Tanık
authors.forename: Ozcan
authors.initials: O
authors.lastname: Karaman
authors.forename: Feyza Yener
authors.initials: FY
authors.lastname: Oztürk
authors.forename: Ayşenur
authors.initials: A
authors.lastname: Ozderya
authors.forename: Hanife
authors.initials: H
authors.lastname: Ozkayalar
authors.forename: Yunus
authors.initials: Y
authors.lastname: Aydın
authors.forename: Yüksel
authors.initials: Y
authors.lastname: Altuntaş
mesh_terms: D000293:Adolescent; D000328:Adult; D018906:Antineoplastic Agents, Alkylating / Q000627:therapeutic use; D054316:Biomarkers, Pharmacological / Q000032:analysis / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000032:analysis / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D003397:Craniopharyngioma / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D015254:DNA Modification Methylases / Q000032:analysis / Q000378:metabolism*; D045643:DNA Repair Enzymes / Q000032:analysis / Q000378:metabolism*; D003606:Dacarbazine / Q000031:analogs & derivatives / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D000077204:Temozolomide; D025521:Tumor Suppressor Proteins / Q000032:analysis / Q000378:metabolism*; D055815:Young Adult
chemical_list: D018906:Antineoplastic Agents, Alkylating; D054316:Biomarkers, Pharmacological; D014408:Biomarkers, Tumor; D025521:Tumor Suppressor Proteins; D003606:Dacarbazine; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D045643:DNA Repair Enzymes; D000077204:Temozolomide