title: High mobility group AT-hook 2 is overexpressed in hepatoblastoma.
abstract: Hepatoblastoma is the most frequent malignant hepatic tumor in children. Expression of high mobility group AT-hook 2, an architectural nuclear factor and marker for hepatic progenitor cells, has not been studied in detail in hepatocellular neoplasms. Immunohistochemical stains using antibodies against high mobility group AT-hook 2, β-catenin, glypican-3, p53, and Ki-67 were performed in 15 hepatoblastomas, 15 fibrolamellar hepatocellular carcinomas, 34 hepatocellular carcinomas (12, ≤30 years old; 22, >30 years old), and 22 hepatic adenomas. High mobility group AT-hook 2 was expressed in all 15 hepatoblastomas, including all fetal and embryonal components, significantly higher than in 41.7% (5/12) of hepatocellular carcinomas of 30 years or younger (P = .001) and in 9% (2/22) of hepatocellular carcinomas of older than 30 years (P < .001). Aberrant β-catenin expression was detected in 80% (12/15) of hepatoblastomas, 41.6% (5/12) of hepatocellular carcinomas of 30 years or younger, and 18.2% (4/22) of hepatocellular carcinomas of older than 30 years. All 15 fibrolamellar hepatocellular carcinomas and 22 hepatic adenomas were negative for high mobility group AT-hook 2 or β-catenin. High mobility group AT-hook 2 and β-catenin expression correlated positively (P = .017; τ = 0.522) in 34 hepatocellular carcinomas. β-Catenin and glypican-3 exhibited a distinct spatial distribution within hepatoblastomas; glypican-3 was more frequently expressed in fetal components (P = .007), whereas β-catenin tended to be more frequently expressed in embryonal components (P = .062). In conclusion, high mobility group AT-hook 2 is expressed in all hepatoblastomas and could be used as a sensitive marker in their diagnosis. High mobility group AT-hook 2 was also expressed in a subset of hepatocellular carcinomas in association with β-catenin expression; this might represent a subtype of hepatocellular carcinoma with hepatic progenitor cell differentiation.
authors.affiliation: Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan, Republic of China.
authors.forename: Chung-Ta
authors.initials: CT
authors.lastname: Lee
authors.forename: Lizhi
authors.initials: L
authors.lastname: Zhang
authors.forename: Taofic
authors.initials: T
authors.lastname: Mounajjed
authors.forename: Tsung-Teh
authors.initials: TT
authors.lastname: Wu
mesh_terms: D018248:Adenoma, Liver Cell / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor; D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D053673:Glypicans / Q000096:biosynthesis; D025743:HMGA2 Protein / Q000096:biosynthesis*; D018197:Hepatoblastoma / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007223:Infant; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D051176:beta Catenin / Q000096:biosynthesis
chemical_list: D014408:Biomarkers, Tumor; D053673:Glypicans; D025743:HMGA2 Protein; D051176:beta Catenin