title: JMJD2A-dependent silencing of Sp1 in advanced breast cancer promotes metastasis by downregulation of DIRAS3.
abstract: Specificity protein 1(Sp1) is a ubiquitous transcription factor and is highly expressed in breast cancer. However, its expression pattern and role in breast cancer progression remain unclear. The purpose of this study is to examine the expression pattern of Sp1 and determine its role in breast cancer progression. Immunohistochemistry (IHC) was performed on breast cancer tissues to reveal the expression pattern of Sp1. Spearman rank correlation was used for clinical statistics. Gene and protein expressions were monitored by IHC analysis, quantitative polymerase chain reaction, and Western blot. Wound-healing and Transwell assays were conducted to assess the role of Sp1 in breast cancer. Co-immunoprecipitation, deletion mutagenesis, chromatin immunoprecipitation, and dual luciferase reporter gene assays were used for investigation of the regulatory network. Sp1 expression was downregulated in late stage breast cancer and in highly invasive breast cancer cell lines. Expression of Sp1 was negatively correlated with TNM staging (P = 0.002) and metastasis status (P = 0.023). Overexpression of Sp1 inhibited breast cancer cell migratory and invasive abilities, whereas knockdown of GTP-binding RAS-like 3 (DIRAS3, also known as ARHI, NOEY2) attenuated the inhibitory effects. Moreover, re-expression of DIRAS3 abolished Sp1 knockdown-mediated cell migration and invasion. Jumonji domain containing 2A (JMJD2A) inhibited Sp1 autoregulation and explains Sp1 expression pattern in breast cancer. Sp1 negatively regulated breast cancer metastasis by transcriptional activation of DIRAS3. Inhibition of Sp1 autoregulation by JMJD2A contributed to Sp1 expression pattern in breast cancer. Our findings provided evidence that targeted therapy against Sp1 might be useful in early stage breast cancer. However, in late stages, development of Sp1 activator may be more promising for breast cancer treatments.
authors.affiliation: Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Xuhui District, Shanghai, 200032, People's Republic of China, 11111010016@fudan.edu.cn.
authors.forename: Liliang
authors.initials: L
authors.lastname: Li
authors.forename: Pan
authors.initials: P
authors.lastname: Gao
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Li
authors.forename: Yiwen
authors.initials: Y
authors.lastname: Shen
authors.forename: Jianhui
authors.initials: J
authors.lastname: Xie
authors.forename: Daming
authors.initials: D
authors.lastname: Sun
authors.forename: Aimin
authors.initials: A
authors.lastname: Xue
authors.forename: Ziqin
authors.initials: Z
authors.lastname: Zhao
authors.forename: Zude
authors.initials: Z
authors.lastname: Xu
authors.forename: Mingchang
authors.initials: M
authors.lastname: Zhang
authors.forename: Beixu
authors.initials: B
authors.lastname: Li
authors.forename: Jieqing
authors.initials: J
authors.lastname: Jiang
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D002465:Cell Movement; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D016329:Sp1 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C117386:DIRAS3 protein, human; D016329:Sp1 Transcription Factor; D056484:Jumonji Domain-Containing Histone Demethylases; C494424:KDM4A protein, human; D020741:rho GTP-Binding Proteins