title: Relationship between alpha-methylacyl-coenzyme A racemase expression and mucin phenotype in gastric cancer.
abstract: Alpha-methylacyl-coenzyme A racemase controls β-oxidation of branched-chain fatty acid and their derivatives. Many investigators have described alpha-methylacyl-coenzyme A racemase expression in various neoplasias and their precursor lesions. Although there have been a few reports regarding alpha-methylacyl-coenzyme A racemase expression in gastric neoplasia, these reports did not discuss the relationship between alpha-methylacyl-coenzyme A racemase expression and mucin phenotype. This study analyzed alpha-methylacyl-coenzyme A racemase expression of gastric carcinomas with regard to mucin phenotype. Alpha-methylacyl-coenzyme A racemase expression was evaluated in 85 cases of gastric biopsies including gastric epithelial neoplasia and nonneoplasia and in 108 cases of surgically resected early gastric cancer. In biopsy cases, alpha-methylacyl-coenzyme A racemase was more highly expressed in neoplasia (69.7%, 23/33) than in nonneoplasia (0%, 0/42) (P = .001). Alpha-methylacyl-coenzyme A racemase was overexpressed in 20.0% (2/10) of cases that were indefinite for neoplasia, and the 2 positive cases were ultimately diagnosed as adenocarcinoma. In resected cases of early gastric adenocarcinoma, alpha-methylacyl-coenzyme A racemase expression significantly correlated with mucin phenotype (P = .003), but not with tumor progression, histologic classification, or clinicopathologic features. Alpha-methylacyl-coenzyme A racemase expression was significantly higher in intestinal-phenotype carcinoma (90.2%, 37/40) than in gastric-phenotype carcinoma (56.3%, 18/31) (P = .006) and also correlated with an increase in CDX2 expression (P = .018) and a decrease in MUC5AC expression (P = .048). This tendency was observed in all histologic types. Our results indicate that alpha-methylacyl-coenzyme A racemase is a useful marker for distinguishing gastric neoplasia from nonneoplasia even at an early stage. Alpha-methylacyl-coenzyme A racemase expression is associated with mucin phenotypes of gastric neoplasia, particularly with the expression of CDX2 and MUC5AC.
authors.affiliation: Division of Molecular and Diagnostic Pathology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan.
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Nozawa
authors.forename: Ken
authors.initials: K
authors.lastname: Nishikura
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ajioka
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Aoyagi
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins / Q000096:biosynthesis; D006801:Humans; D007150:Immunohistochemistry; D009077:Mucins / Q000032:analysis*; D010641:Phenotype; D019998:Racemases and Epimerases / Q000032:analysis / Q000096:biosynthesis*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins; D009077:Mucins; D019998:Racemases and Epimerases; C108352:alpha-methylacyl-CoA racemase