title: IMP3 expression is correlated with histologic grade of lung adenocarcinoma.
abstract: Insulin-like growth factor II mRNA binding protein 3 is an oncofetal protein that is expressed in multiple malignancies. This study aimed to determine the correlation of insulin-like growth factor II mRNA binding protein 3 expression with histologic grade of lung adenocarcinoma. Eighty-nine cases, including 11 atypical adenomatous hyperplasias, 10 pure bronchioloalveolar carcinomas, 36 well-differentiated adenocarcinomas and 41 moderately or poorly differentiated adenocarcinomas, were immunohistochemically studied using a monoclonal antibody against insulin-like growth factor II mRNA binding protein 3. Twenty-nine (70.7%) of 41 moderately to poorly differentiated adenocarcinomas were positive for insulin-like growth factor II mRNA binding protein 3, with 26 (89.7%) tumors demonstrating either a strong staining or staining in greater than 30% of tumor cells. Four (40.0%) of 10 bronchioloalveolar carcinomas and 13 (36.1%) of 36 well-differentiated adenocarcinomas exhibited insulin-like growth factor II mRNA binding protein 3 positivity with a variable degree and percentage of tumor cells staining. When bronchioloalveolar carcinomas were present in a pure form or as a component of adenocarcinomas, positive insulin-like growth factor II mRNA binding protein 3 staining was always patchy, with less than 20% of tumor cells stained. Overall, the frequency of positive insulin-like growth factor II mRNA binding protein 3 staining was lower in bronchioloalveolar carcinomas and well-differentiated adenocarcinomas compared to moderately/poorly differentiated adenocarcinomas (P < .01). No insulin-like growth factor II mRNA binding protein 3 signal was detected in any case of atypical adenomatous hyperplasia. These findings show that insulin-like growth factor II mRNA binding protein 3 is strongly and diffusely expressed in a large proportion of moderately/poorly differentiated lung adenocarcinomas, in particular in the solid component of mixed subtype adenocarcinomas, less frequently expressed in well-differentiated adenocarcinomas and bronchioloalveolar carcinomas, and negative in atypical adenomatous hyperplasias. The higher frequency of expression in moderately/poorly differentiated adenocarcinomas suggests that insulin-like growth factor II mRNA binding protein 3 expression may be associated with an aggressive biological behavior.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA.
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Findeis-Hosey
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.forename: Betsy O
authors.initials: BO
authors.lastname: Spaulding
authors.forename: Hanlin L
authors.initials: HL
authors.lastname: Wang
authors.forename: Haodong
authors.initials: H
authors.lastname: Xu
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology*; D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000378:metabolism / Q000473:pathology; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology*; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D009367:Neoplasm Staging; D011230:Precancerous Conditions / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000096:biosynthesis*
chemical_list: C498780:IGF2BP3 protein, human; D009363:Neoplasm Proteins; D016601:RNA-Binding Proteins