title: Tenascin-X is a novel diagnostic marker of malignant mesothelioma.
abstract: Tenascin XB (TNXB) was previously identified as a gene that is more highly expressed in malignant mesothelioma compared with ovarian/peritoneal serous carcinoma based on gene expression array analysis. The objective of this study was to validate this finding at the mRNA and protein levels. Effusions (n = 91; 71 ovarian carcinomas, 10 breast carcinomas, and 10 malignant mesotheliomas) were assayed for TNXB mRNA expression using quantitative polymerase chain reaction. Tenascin-X protein expression was studied in 183 effusions (137 carcinomas of different origin, 37 mesotheliomas, and 9 reactive effusions) and 178 solid lesions (122 ovarian/peritoneal carcinomas and 56 mesotheliomas) using immunohistochemistry. Quantitative polymerase chain reaction analysis showed significantly higher TNXB mRNA level in mesotheliomas compared with ovarian and breast carcinomas (P < 0.001). By immunohistochemistry, tenascin-X protein expression was significantly higher in malignant mesothelioma compared with metastatic carcinoma in effusions (34 of 37 vs. 31 of 137 positive cases; sensitivity = 92% and specificity = 77%; P < 0.001). Reactive mesothelial cells had focal or no tenascin-X expression. Tenascin-X protein was detected in 41 of 56 mesothelioma biopsy specimens and was uniformly absent from all 122 ovarian carcinomas (sensitivity = 73% and specificity = 100%; P < 0.001). Our data suggest that tenascin-X may be a new diagnostic marker of malignant mesothelioma in the differential diagnosis of cancers involving the serosal cavities, particularly in the differential diagnosis between this tumor and ovarian/peritoneal serous carcinoma.
authors.affiliation: Department of Pathology, Norwegian Radium Hospital, Norway.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yuan
authors.forename: Dag André
authors.initials: DA
authors.lastname: Nymoen
authors.forename: Helene Tuft
authors.initials: HT
authors.lastname: Stavnes
authors.forename: Anne Katrine
authors.initials: AK
authors.lastname: Rosnes
authors.forename: Ola
authors.initials: O
authors.lastname: Bjørang
authors.forename: Chuanyue
authors.initials: C
authors.lastname: Wu
authors.forename: Jahn M
authors.initials: JM
authors.lastname: Nesland
authors.forename: Ben
authors.initials: B
authors.lastname: Davidson
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008654:Mesothelioma / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D016066:Pleural Effusion, Malignant / Q000175:diagnosis* / Q000235:genetics; D011237:Predictive Value of Tests; D012333:RNA, Messenger / Q000378:metabolism; D012334:RNA, Neoplasm / Q000032:analysis; D019063:Tenascin / Q000235:genetics / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D019063:Tenascin; C081865:tenascin X