Insulin-like growth factor type I receptor gene expression and obesity in esophageal adenocarcinoma.
The objective of this exploratory study was to evaluate the role of the insulin-like growth factor I receptor (IGF-IR) in esophageal adenocarcinoma (EADC). Using quantitative PCR, we studied IGF-IR mRNA expression in 52 well-characterized surgically resected EADC and matched histologically normal esophageal tissues, and examined IGF-IR expression levels in relation to clinicopathologic characteristics, body mass index (BMI), and the common IGF-IR polymorphism (G1013A), recently proposed to modify risk of obesity for EADC. Expression levels of IGF-IR mRNA were not significantly different between EADC and matched histologically normal esophageal epithelia. Although no significant associations were found between IGF-IR expression and BMI, tumor differentiation, stage or survival, when stratified by genotype, patients with the polymorphic A variant had significantly higher IGF-IR expression in EADC tissues compared with matched normal epithelia. These findings suggest that G1013A most likely modulates IGF-IR function, possibly by influencing gene transcription or mRNA stability, and represents a plausible mechanistic link underlying the association between obesity and esophageal malignancy.
Zhao
Ronghua
R
Department of Surgery, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Macdonald
Kimberley
K
Casson
Alan G
AG
D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000368:Aged; D001483:Base Sequence; D015992:Body Mass Index; D017931:DNA Primers; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D017526:Receptor, IGF Type 1 / Q000235:genetics*
D017931:DNA Primers; D012333:RNA, Messenger; D017526:Receptor, IGF Type 1