title: IQGAP1 modulates the proliferation and invasion of thyroid cancer cells in response to estrogen.
abstract: Thyroid cancer is an endocrine malignancy with a high incidence rate, which is affected by female hormones, particularly estrogens, in its growth and progression. IQ-domain GTPase-activating protein 1 (IQGAP1) is overexpressed in a range of types of cancer and is reported to interact with estrogen receptor α (ERα) in breast cancer cells. However, the association between IQGAP1 and ERα in thyroid cancer cells remains to be elucidated. In this study, the role of IQGAP1 in thyroid cancer cells was examined. The expression of IQGAP1 (190 kDa) was analyzed using western blot analysis, which indicated that IQGAP1 was overexpressed in thyroid cancer tissues and FTC133 cells. However, IQGAP1 knockdown in the FTC133 cells led to a significant downregulation in ERα transcriptional activity, cell proliferation, cell adhesion and cell invasion under 17β-estradiol (E2) conditions. Furthermore, ERα knockdown inhibited the enhanced protein expression levels of phosphorylated ERK1/2 and cyclin D1, which were induced by the overexpression of IQGAP1. Co-immunoprecipitation was also performed in thyroid cancer cells and the results suggested that IQGAP1 directly interacted with ERα in the FTC133 cells and the co-transfected COS-7 cells. Taken together, these findings revealed that IQGAP1 may directly interact with ERα and serve as a signal integrator, mediating ERα transcriptional activity, cell proliferation and cell invasion during the progression of thyroid cancer.
authors.affiliation: Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Meng
authors.affiliation: Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China.
authors.forename: Wenxun
authors.initials: W
authors.lastname: Wu
authors.affiliation: Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China.
authors.forename: Zhifu
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China.
authors.forename: Guijun
authors.initials: G
authors.lastname: Qin
mesh_terms: D000328:Adult; D000818:Animals; D019556:COS Cells; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002522:Chlorocebus aethiops; D019938:Cyclin D1 / Q000235:genetics; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D004967:Estrogens / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D019950:Mitogen-Activated Protein Kinase 1 / Q000235:genetics; D048052:Mitogen-Activated Protein Kinase 3 / Q000235:genetics; D009361:Neoplasm Invasiveness / Q000235:genetics / Q000473:pathology*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D013961:Thyroid Gland / Q000378:metabolism / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D020703:ras GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D004967:Estrogens; C101203:IQ motif containing GTPase activating protein 1; D034741:RNA, Small Interfering; D020703:ras GTPase-Activating Proteins; D019938:Cyclin D1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3