title: Expression and significance of IGF-1 and IGF-1R in thyroid nodules.
abstract: There are limitations in the diagnosis of thyroid nodules, especially follicular lesions, and their pathogenesis remains unclear. Insulin-like growth factor-1 (IGF-1) has been implicated in tumor cell apoptosis, transformation, invasion, and metastasis; however, its role in thyroid nodules is undetermined. The aim of this study is to investigate the relationship between expression of IGF-1 and thyroid nodule, and evaluate the role of IGF-1 in differential diagnosis and pathogenetic function of benign and malignant thyroid nodules. Sixty-two paraffin-embedded thyroid tissues from patients with thyroid nodules were selected, including 18 follicular adenomas (FA), 17 nodular goiters, 13 papillary thyroid carcinomas (PTC), 2 follicular thyroid carcinomas, and 12 normal controls. IGF-1 and IGF-1R protein and mRNA expression was detected by immunohistochemistry (IHC) and real-time quantitative PCR (qRT-PCR), respectively. Grouping comparisons were employed among the above groups based on the clinical and pathological subtypes. IGF-1 and IGF-1R expression was significantly higher in FA, nodular goiters, and PTC than that in the controls (all P < 0.01). Similarly, IGF-1 mRNA expression was also significantly higher in FA (P < 0.05), nodular goiters (P < 0.01), and PTC (P < 0.01) compared with the controls. IGF-1R mRNA expression was also significantly higher in FA, nodular goiters, and PTC (all P < 0.01) compared with the controls. Compared with FA and nodular goiters, PTC showed significantly higher IGF-1 and IGF-1R protein (P < 0.01, P < 0.05, respectively) and mRNA expression (P < 0.01, P < 0.05, respectively). IGF-1 probably plays an important role in the genesis and development of certain solid cold thyroid nodules, including PTC, nodular goiters, and FA. Detection of IGF-1 and IGF-1R expression in thyroid tissues by IHC or qRT-PCR is hard to distinguish malignant from benign lesions.
authors.affiliation: Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Shaanxi Province, Xi'an, 710061, China.
authors.forename: Ying-Jian
authors.initials: YJ
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Qiang
authors.forename: Jing
authors.initials: J
authors.lastname: Shi
authors.forename: Si-Qing
authors.initials: SQ
authors.lastname: Lv
authors.forename: Mei-Ju
authors.initials: MJ
authors.lastname: Ji
authors.forename: Bing-Yin
authors.initials: BY
authors.lastname: Shi
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D002291:Carcinoma, Papillary; D005260:Female; D015870:Gene Expression; D006044:Goiter, Nodular / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007334:Insulin-Like Growth Factor I / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D017526:Receptor, IGF Type 1 / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D016606:Thyroid Nodule / Q000175:diagnosis* / Q000378:metabolism*
chemical_list: C583557:IGF1 protein, human; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1