title: NHERF1, a novel GPER associated protein, increases stability and activation of GPER in ER-positive breast cancer.
abstract: G protein-coupled estrogen receptor (GPER) plays an important role in mediating the effects of estradiol. High levels of GPER have been implicated to associate with the malignant progress of invasive breast cancer (IBC). However, the mechanisms by which GPER protein levels were regulated remain unclear. In this study, PDZ protein Na+/H+ exchanger regulatory factor (NHERF1) was found to interact with GPER in breast cancer cells. This interaction was mediated by the PDZ2 domain of NHERF1 and the carboxyl terminal PDZ binding motif of GPER. NHERF1 was demonstrated to facilitate GPER expression at post-transcriptional level and improve GPER protein stability by inhibiting the receptor degradation via ubiquitin-proteasome pathway in a GPER/NHERF1 interaction-dependent manner. In addition, GPER protein levels are positively associated with NHERF1 protein levels in a panel of estrogen receptor (ER)-positive breast cancer cells. Furthermore, analysis of clinical IBC data from The Cancer Genome Atlas (TCGA) showed no significant difference in GPER mRNA levels between ER-positive IBC and normal breast tissues. However, gene set enrichment analysis (GSEA) showed that GPER signaling is ultra-activated in ER-positive IBC when compared with normal and its activation is positively associated with NHERF1 mRNA levels. Taken together, our findings identify NHERF1 as a new binding partner for GPER and its overexpression promotes protein stability and activation of GPER in ER-positive IBC. Our data indicate that regulation of GPER stability by NHERF1 may contribute to GPER-mediated carcinogenesis in ER-positive IBC.
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Meng
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.|Beijing Key Laboratory for Tumor Invasion and Metastasis, Beijing International Cooperation Base for Science and Technology on China-UK Cancer Research, Beijing, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Qin
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.|Beijing Key Laboratory for Tumor Invasion and Metastasis, Beijing International Cooperation Base for Science and Technology on China-UK Cancer Research, Beijing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Xiong
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.|Beijing Key Laboratory for Tumor Invasion and Metastasis, Beijing International Cooperation Base for Science and Technology on China-UK Cancer Research, Beijing, China.
authors.forename: Junfang
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Tao
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.
authors.forename: Qiqi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.|Beijing Key Laboratory for Tumor Invasion and Metastasis, Beijing International Cooperation Base for Science and Technology on China-UK Cancer Research, Beijing, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.|Molecular Laboratory for Gene Therapy and Tooth Regeneration, Capital Medical University School of Stomatology, Beijing, China.
authors.forename: Songlin
authors.initials: S
authors.lastname: Wang
authors.affiliation: Beijing Key Laboratory for Tumor Invasion and Metastasis, Beijing International Cooperation Base for Science and Technology on China-UK Cancer Research, Beijing, China.|Cardiff China Medical Research Collaborative, Cardiff University School of Medicine, Cardiff, United Kingdom.
authors.forename: Wen G
authors.initials: WG
authors.lastname: Jiang
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China.|Beijing Key Laboratory for Tumor Invasion and Metastasis, Beijing International Cooperation Base for Science and Technology on China-UK Cancer Research, Beijing, China.
authors.forename: Junqi
authors.initials: J
authors.lastname: He
mesh_terms: D001665:Binding Sites / Q000235:genetics; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D057809:HEK293 Cells; D006801:Humans; D061986:MCF-7 Cells; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D034622:RNA Interference; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D017923:Sodium-Hydrogen Exchangers / Q000235:genetics / Q000378:metabolism*
chemical_list: D047628:Estrogen Receptor alpha; C109584:GPER1 protein, human; D010750:Phosphoproteins; D011960:Receptors, Estrogen; D043562:Receptors, G-Protein-Coupled; D017923:Sodium-Hydrogen Exchangers; C093376:sodium-hydrogen exchanger regulatory factor
keywords: EBP50; G protein-coupled receptor; carcinogenesis; protein degradation; protein-protein interaction