Topoisomerase IIalpha mRNA and protein expression in ovarian carcinoma: correlation with clinicopathological factors and prognosis.
Topoisomerase IIalpha (Top IIalpha) is a nuclear enzyme that plays a central role in DNA metabolism, and is a molecular target for a variety of chemotherapeutic agents. Top IIalpha has recently gained attention as a biomarker for therapy response and patient survival. In this study, we attempted to assess the feasibility of measuring Top IIalpha gene expression in RNA, isolated from archival formalin-fixed paraffin-embedded tissue specimens, which are used routinely in pathology laboratories. We have employed a new technique on the basis of magnetic particles' separation and purification of nucleic acids, and evaluated both protein and mRNA expressions from the same routinely processed tissue blocks. We investigated the expression of Top IIalpha mRNA and protein by real-time reverse transcription polymerase chain reaction and immunohistochemistry, in a cohort of 133 primary ovarian carcinomas, and evaluated the association between Top IIalpha expression and clincopathological variables as well as patient outcome. Elevated Top IIalpha mRNA expression was observed in high-grade tumors (P=0.003) and advanced stage disease (P=0.011). In univariate Kaplan-Meier analysis, patients with higher expression of Top IIalpha nuclear protein had a significantly decreased overall survival (P=0.045). Interestingly, we detected cytoplasmic protein expression of Top IIalpha in a subset of samples. Cytoplasmic expression of Top IIalpha was associated with the expression of chromosomal region maintenance/exportin 1 (CRM1)-a nuclear export protein (P=0.008). Our study suggests that Top IIalpha overexpression is involved in the progression of ovarian cancer in a subset of the patients. Our results encourage the further evaluation of the prognostic and predictive values of Top IIalpha expression in ovarian carcinoma, which might help to assess the patients' risk profile, and the planning of an individualized therapy.
Faggad
Areeg
A
Institute of Pathology, Charité University Hospital, Berlin, Germany.
Darb-Esfahani
Silvia
S
Wirtz
Ralph
R
Sinn
Bruno
B
Sehouli
Jalid
J
Könsgen
Dominique
D
Lage
Hermann
H
Weichert
Wilko
W
Noske
Aurelia
A
Budczies
Jan
J
Müller
Berit M
BM
Buckendahl
Ann-Christin
AC
Röske
Annika
A
Eldin Elwali
Nasr
N
Dietel
Manfred
M
Denkert
Carsten
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000032:analysis; D002277:Carcinoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D004250:DNA Topoisomerases, Type II / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018572:Disease-Free Survival; D005260:Female; D005557:Formaldehyde; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D028884:Karyopherins / Q000096:biosynthesis; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D016612:Paraffin Embedding; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis; D018160:Receptors, Cytoplasmic and Nuclear / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016707:Tissue Fixation; D000097606:Exportin 1 Protein
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D004250:DNA Topoisomerases, Type II; D004268:DNA-Binding Proteins; D005557:Formaldehyde; D028884:Karyopherins; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D000097606:Exportin 1 Protein