1
|
Somsen BA, Sijbesma E, Leysen S, Honzejkova K, Visser EJ, Cossar PJ, Obšil T, Brunsveld L, Ottmann C. Molecular basis and dual ligand regulation of tetrameric Estrogen Receptor α/14-3-3ζ protein complex. J Biol Chem 2023:104855. [PMID: 37224961 PMCID: PMC10302166 DOI: 10.1016/j.jbc.2023.104855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 05/26/2023] Open
Abstract
Therapeutic strategies targeting Nuclear Receptors (NRs) beyond their endogenous ligand binding pocket have gained significant scientific interest, driven by a need to circumvent problems associated with drug resistance and pharmacological profile. The hub protein 14-3-3 is an endogenous regulator of various NRs, providing a novel entry point for small molecule modulation of NR activity. Exemplified, 14-3-3 binding to the C-terminal F-domain of the Estrogen Receptor alpha (ERα), and small molecule stabilization of the ERα/14-3-3ζ protein complex by the natural product Fusicoccin A (FC-A), was demonstrated to downregulate ERα-mediated breast cancer proliferation. This presents a novel drug discovery approach to target ERα, however, structural and mechanistic insights into ERα/14-3-3 complex formation are lacking. Here, we provide an in-depth molecular understanding of the ERα/14-3-3ζ complex by isolating 14-3-3ζ in complex with an ERα protein construct comprising its Ligand Binding Domain (LBD) and phosphorylated F-domain. Bacterial co-expression and co-purification of the ERα/14-3-3ζ complex, followed by extensive biophysical and structural characterization, revealed a tetrameric complex between the ERα homodimer and the 14-3-3ζ homodimer. 14-3-3ζ binding to ERα, and ERα/14-3-3ζ complex stabilization by FC-A, appeared to be orthogonal to ERα endogenous agonist (E2) binding, E2-induced conformational changes, and cofactor recruitment. Similarly, the ERα antagonist 4-hydroxytamoxifen inhibited cofactor recruitment to the ERα LBD while ERα was bound to 14-3-3ζ. Furthermore, stabilization of the ERα/14-3-3ζ protein complex by FC-A was not influenced by the disease-associated and 4-hydroxytamoxifen resistant ERα-Y537S mutant. Together, these molecular and mechanistic insights provide direction for targeting ERα via the ERα/14-3-3 complex as an alternative drug discovery approach.
Collapse
Affiliation(s)
- Bente A Somsen
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - Eline Sijbesma
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - Seppe Leysen
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - Karolina Honzejkova
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Prague, Czech Republic
| | - Emira J Visser
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - Peter J Cossar
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - Tomáš Obšil
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Prague, Czech Republic
| | - Luc Brunsveld
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands.
| | - Christian Ottmann
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands.
| |
Collapse
|
2
|
Interactions between 14-3-3 Proteins and Actin Cytoskeleton and Its Regulation by microRNAs and Long Non-Coding RNAs in Cancer. ENDOCRINES 2022. [DOI: 10.3390/endocrines3040057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
14-3-3s are a family of structurally similar proteins that bind to phosphoserine or phosphothreonine residues, forming the central signaling hub that coordinates or integrates various cellular functions, thereby controlling many pathways important in cancer, cell motility, cell death, cytoskeletal remodeling, neuro-degenerative disorders and many more. Their targets are present in all cellular compartments, and when they bind to proteins they alter their subcellular localization, stability, and molecular interactions with other proteins. Changes in environmental conditions that result in altered homeostasis trigger the interaction between 14-3-3 and other proteins to retrieve or rescue homeostasis. In circumstances where these regulatory proteins are dysregulated, it leads to pathological conditions. Therefore, deeper understanding is needed on how 14-3-3 proteins bind, and how these proteins are regulated or modified. This will help to detect disease in early stages or design inhibitors to block certain pathways. Recently, more research has been devoted to identifying the role of MicroRNAs, and long non-coding RNAs, which play an important role in regulating gene expression. Although there are many reviews on the role of 14-3-3 proteins in cancer, they do not provide a holistic view of the changes in the cell, which is the focus of this review. The unique feature of the review is that it not only focuses on how the 14-3-3 subunits associate and dissociate with their binding and regulatory proteins, but also includes the role of micro-RNAs and long non-coding RNAs and how they regulate 14-3-3 isoforms. The highlight of the review is that it focuses on the role of 14-3-3, actin, actin binding proteins and Rho GTPases in cancer, and how this complex is important for cell migration and invasion. Finally, the reader is provided with super-resolution high-clarity images of each subunit of the 14-3-3 protein family, further depicting their distribution in HeLa cells to illustrate their interactions in a cancer cell.
Collapse
|
3
|
Fan X, Cui L, Zeng Y, Song W, Gaur U, Yang M. 14-3-3 Proteins Are on the Crossroads of Cancer, Aging, and Age-Related Neurodegenerative Disease. Int J Mol Sci 2019; 20:ijms20143518. [PMID: 31323761 PMCID: PMC6678932 DOI: 10.3390/ijms20143518] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/15/2019] [Accepted: 07/16/2019] [Indexed: 12/14/2022] Open
Abstract
14-3-3 proteins are a family of conserved regulatory adaptor molecules which are expressed in all eukaryotic cells. These proteins participate in a variety of intracellular processes by recognizing specific phosphorylation motifs and interacting with hundreds of target proteins. Also, 14-3-3 proteins act as molecular chaperones, preventing the aggregation of unfolded proteins under conditions of cellular stress. Furthermore, 14-3-3 proteins have been shown to have similar expression patterns in tumors, aging, and neurodegenerative diseases. Therefore, we put forward the idea that the adaptor activity and chaperone-like activity of 14-3-3 proteins might play a substantial role in the above-mentioned conditions. Interestingly, 14-3-3 proteins are considered to be standing at the crossroads of cancer, aging, and age-related neurodegenerative diseases. There are great possibilities to improve the above-mentioned diseases and conditions through intervention in the activity of the 14-3-3 protein family.
Collapse
Affiliation(s)
- Xiaolan Fan
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Lang Cui
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Yao Zeng
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Wenhao Song
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Uma Gaur
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Mingyao Yang
- Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| |
Collapse
|
4
|
Compounds from Cynomorium songaricum with Estrogenic and Androgenic Activities Suppress the Oestrogen/Androgen-Induced BPH Process. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 2017:6438013. [PMID: 28588640 PMCID: PMC5447316 DOI: 10.1155/2017/6438013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/09/2017] [Indexed: 11/22/2022]
Abstract
Objective To investigate the phytoestrogenic and phytoandrogenic activities of compounds isolated from CS and uncover the role of CS in prevention of oestrogen/androgen-induced BPH. Methods Cells were treated with CS compounds, and immunofluorescence assay was performed to detect the nuclear translocation of ERα or AR in MCF-7 or LNCaP cells; luciferase reporter assay was performed to detect ERs or AR transcriptional activity in HeLa or AD293 cells; MTT assay was performed to detect the cell proliferation of MCF-7 or LNCaP cells. Oestrogen/androgen-induced BPH model was established in rat and the anti-BPH, anti-estrogenic, and anti-androgenic activities of CS in vivo were further investigated. Results The nuclear translocation of ERα was stimulated by nine CS compounds, three of which also stimulated AR translocation. The transcriptional activities of ERα and ERβ were induced by five compounds, within which only ECG induced AR transcriptional activity as well. Besides, ECG stimulated the proliferation of both MCF-7 cells and LNCaP cells. CS extract suppressed oestrogen/androgen-induced BPH progress in vivo by downregulation of E2 and T level in serum and alteration of the expressions of ERα, ERβ, and AR in the prostate. Conclusion Our data demonstrates that compounds from CS exhibit phytoestrogenic and phytoandrogenic activities, which may contribute to inhibiting the oestrogen/androgen-induced BPH development.
Collapse
|
5
|
Lee II, Maniar K, Lydon JP, Kim JJ. Akt regulates progesterone receptor B-dependent transcription and angiogenesis in endometrial cancer cells. Oncogene 2016; 35:5191-201. [PMID: 26996671 PMCID: PMC5031502 DOI: 10.1038/onc.2016.56] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 01/20/2016] [Accepted: 02/08/2016] [Indexed: 12/14/2022]
Abstract
Progestins have long been used clinically for the treatment of endometrial cancers, however, the response rates to progestin therapy vary and the molecular mechanisms behind progestin insensitivity are poorly understood. We hypothesized that in PTEN mutated endometrial cancers, hyperactive Akt signaling downregulates Progesterone Receptor B (PRB) transcriptional activity, leading to overall impaired progestin responses. We report that inhibition of Akt with the Akt inhibitor, MK-2206 (MK), in conjunction with progestin (R5020) treatment, is sufficient to upregulate a subset of PRB target genes in Ishikawa cells stably expressing PRB (PRB-Ishikawa). Through gene ontology analysis of Akt-regulated PRB target genes, angiogenesis was found to be the principle process regulated by Akt-PRB. To further interrogate the mechanism by which Akt modulates PRB transcriptional activity, ChIP-Mass Spectrometry was performed to identify potential cofactors that differentially interact with PRB in the presence of the R5020 and MK+R5020. 14-3-3σ was identified as a protein enriched in the MK+R5020 dataset, and it was demonstrated that 14-3-3σ is required for the upregulation in PRB target gene expression following inhibition of Akt. In order to determine the ramifications of MK+R5020 treatment on angiogenesis, in vitro assays were performed and combinatorial MK+R5020 treatment significantly decreased endothelial cell invasion and tube formation more than MK or R5020 treatment alone. Furthermore, we found that combinatorial MK-2206+Progesterone treatments decreased angiogenesis and proliferation in the Ptend/d conditional mouse model of endometrial cancer. Taken together, these findings suggest that a combinatorial therapeutic approach utilizing Akt inhibitors with progestins may improve the efficacy of progestin therapy for the treatment of endometrial cancer.
Collapse
Affiliation(s)
- I I Lee
- Division of Reproductive Science in Medicine, Department of Obstetrics and Gynecology, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - K Maniar
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - J P Lydon
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - J J Kim
- Division of Reproductive Science in Medicine, Department of Obstetrics and Gynecology, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| |
Collapse
|
6
|
Haonon O, Rucksaken R, Pinlaor P, Pairojkul C, Chamgramol Y, Intuyod K, Onsurathum S, Khuntikeo N, Pinlaor S. Upregulation of 14-3-3 eta in chronic liver fluke infection is a potential diagnostic marker of cholangiocarcinoma. Proteomics Clin Appl 2015; 10:248-56. [PMID: 26435198 DOI: 10.1002/prca.201500019] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 08/20/2015] [Accepted: 09/24/2015] [Indexed: 01/16/2023]
Abstract
PURPOSE To discover protein markers in chronic/advanced opisthorchiasis for the early detection of Opisthorchis viverrini (OV)-associated cholangiocarcinoma (CCA). EXPERIMENTAL DESIGN Liver tissues derived from normal hamsters and those with chronic/advanced opisthorchiasis (n = 5 per group) were subjected to 2DE and LC-MS/MS. Candidate protein expression was confirmed in hamster models and human CCA tissue microarray (TMA) using immunohistochemistry and Western blot. RESULT Proteomics analysis detected 14-3-3 eta only in infected hamsters, not in uninfected controls. Immunohistochemistry and Western blot analysis confirmed low expression of 14-3-3 eta in normal hamster livers and demonstrated increased expression through time in infected livers. This protein was also observed in parasite organs, especially during the chronic phase of opisthorchiasis. Moreover, increased expression of 14-3-3 eta, relative to normal hamster livers, was observed during the early stage of CCA induced by OV infection and administration of N-nitrosodimethylamine. Immunohistochemical analysis of human TMA revealed that 14-3-3 eta was highly expressed in CCA (84.23%, 187/222 cases) but was not found in hepatocellular carcinoma or healthy liver tissues. CONCLUSIONS AND CLINICAL RELEVANCE 14-3-3 eta protein has potential as a screening and early diagnostic marker for CCA.
Collapse
Affiliation(s)
- Ornuma Haonon
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Rucksak Rucksaken
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Porntip Pinlaor
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Centre for Research and Development in Medical Diagnostic Laboratory, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Chawalit Pairojkul
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Department of Pathology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Yaovalux Chamgramol
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Department of Pathology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Kitti Intuyod
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Biomedical Science Program, Graduate School, Khon Kaen University, Khon Kaen, Thailand
| | - Sudarat Onsurathum
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Narong Khuntikeo
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Department of Surgery, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Somchai Pinlaor
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| |
Collapse
|
7
|
Chen DY, Dai DF, Hua Y, Qi WQ. p53 suppresses 14-3-3γ by stimulating proteasome-mediated 14-3-3γ protein degradation. Int J Oncol 2014; 46:818-24. [PMID: 25384678 DOI: 10.3892/ijo.2014.2740] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 09/26/2014] [Indexed: 11/05/2022] Open
Abstract
14-3-3 proteins are a family of highly conserved polypeptides that interact with a large number of proteins and play a role in a wide variety of cellular processes. 14-3-3 proteins have been demonstrated overexpressed in several cancers and serving as potential oncogenes. In a previous study we showed one isoform of the 14-3-3 family, 14-3-3γ was negatively regulated by p53 through binding to its promoter and inhibiting its transcription. In the present study we investigated both p53 and 14-3-3γ protein levels in human lung cancerous tissues and normal lung tissues. We found 14-3-3γ expression correlated to p53 overexpression in lung cancer tissues. Ecotopic expression of wild-type p53, but not mutant p53 (R175H) suppressed both endogenous and exogenous 14-3-3γ in colon and lung cancer cell lines. Further examination demonstrated that p53 interacted with C-terminal domain of 14-3-3γ and induced 14-3-3γ ubiquitination. MG132, a specific inhibitor of the 26S proteasome, could block the effect of p53 on 14-3-3γ protein levels, suggesting that p53 suppressed 14-3-3γ by stimulating the process of proteasome-mediated degradation of 14-3-3γ. These results indicate that the inhibitory effect of p53 on 14-3-3γ is mediated also by a post-transcriptional mechanism. Loss of p53 function may result in upregulation of 14-3-3γ in lung cancers.
Collapse
Affiliation(s)
- De-Yu Chen
- Institute of Oncology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Dong-Fang Dai
- Institute of Oncology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Ye Hua
- Institute of Oncology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| | - Wen-Qing Qi
- Institute of Oncology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001, P.R. China
| |
Collapse
|
8
|
Reversal of chemosensitivity and induction of cell malignancy of a non-malignant prostate cancer cell line upon extracellular vesicle exposure. Mol Cancer 2013; 12:118. [PMID: 24103426 PMCID: PMC3851868 DOI: 10.1186/1476-4598-12-118] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 09/16/2013] [Indexed: 02/03/2023] Open
Abstract
Background Extracellular vesicle (EV) trafficking is a fundamental cellular process that occurs in cells and is required for different aspects of pathophysiology. EV trafficking leads to changes in cellular function including apoptosis, angiogenesis and proliferation required for increased tumor formation. Results We report several phenotypic changes mediated by EVs isolated from non-malignant and malignant prostate cells as well as patient biopsied prostate tumor samples. EVs can reverse the resistance of prostate cancer cells to camptothecin EVs isolated from non-malignant PrECs (Prostate Epithelial Cells) can reverse soft agar colony formation of malignant DU145 cells, with the reciprocal effect observed. Isolation of EVs from 2 Gleason grade 8 prostate cancer patients significantly induced soft agar colony formation of non-malignant PrECs. We have identified proteins via antibody and Mass spectrometry analysis that may be responsible for the phenotypic changes. Mass spectrometry analysis of protein lysates using ProteoIQ revealed protein candidates associated with gene ontology annotations that may be responsible for this phenotypic change. Ingenuity Pathway Analysis was used to identify statistically relevant canonical pathways and functions associated the protein IDs and expression values obtained using ProteoIQ. Western blot analysis confirmed the increase of 14-3-3 zeta, pRKIP and prohibitin protein levels in PrEC cells co-cultured with patient EVs. 14-3-3 proteins were also found as common proteins of 3 other Gleason grade 8 patients. Conclusion Our study provides a rational basis to further investigate putative proteins, such as 14-3-3 and prohibitin and genetic factors that may be responsible for phenotypic changes that are associated with prostate cancer progression.
Collapse
|
9
|
De S, Kline D. Evidence for the requirement of 14-3-3eta (YWHAH) in meiotic spindle assembly during mouse oocyte maturation. BMC DEVELOPMENTAL BIOLOGY 2013; 13:10. [PMID: 23547714 PMCID: PMC3620909 DOI: 10.1186/1471-213x-13-10] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 03/13/2013] [Indexed: 11/10/2022]
Abstract
BACKGROUND The 14-3-3 (YWHA) proteins are central mediators in various cellular signaling pathways regulating development and growth, including cell cycle regulation. We previously reported that all seven mammalian 14-3-3 isoforms are expressed in mouse oocytes and eggs and that, 14-3-3η (YWHAH) accumulates and co-localizes in the region of meiotic spindle in mouse eggs matured in vivo. Therefore, we investigated the role of 14-3-3η in spindle formation during mouse oocyte maturation. RESULTS Examination of oocytes matured in vitro demonstrated that 14-3-3η accumulates in both meiosis I and II spindles. To explore if 14-3-3η interacts directly with α-tubulin in meiotic spindles, we performed an in situ proximity ligation assay that can detect intracellular protein-protein interactions at the single molecule level and which allows visualization of the actual interaction sites. This assay revealed a marked interaction between 14-3-3η and α-tubulin at the metaphase II spindle. To demonstrate a functional role for 14-3-3η in oocyte maturation, mouse oocytes were microinjected with a translation-blocking morpholino oligonucleotide against 14-3-3η mRNA to reduce 14-3-3η protein synthesis during oocyte maturation. Meiotic spindles in those cells were examined by immunofluorescence staining of 14-3-3η and α-tubulin along with observation of DNA. In 76% of cells injected with the morpholino, meiotic spindles were found to be deformed or absent and there was reduced or no accumulation of 14-3-3η in the spindle region. Those cells contained clumped chromosomes, with no polar body formation. Immunofluorescence staining of 14-3-3η and α-tubulin in control eggs matured in vitro from uninjected oocytes and oocytes microinjected with the ineffective, inverted form of a morpholino against 14-3-3η, a morpholino against 14-3-3γ, or deionized water showed normal, bipolar spindles. CONCLUSIONS The results indicate that 14-3-3η is essential for normal meiotic spindle formation during in vitro maturation of mouse oocytes, in part by interacting with α-tubulin, to regulate the assembly of microtubules. These data add to our understanding of the roles of 14-3-3 proteins in mouse oocyte maturation and mammalian reproduction.
Collapse
Affiliation(s)
- Santanu De
- Department of Biological Sciences, Kent State University, Kent, OH 44242, USA
| | | |
Collapse
|
10
|
Ito M, Urano T, Hiroi H, Momoeda M, Saito M, Hosokawa Y, Tsutsumi R, Zenri F, Koizumi M, Nakae H, Horie-Inoue K, Fujii T, Yano T, Kozuma S, Inoue S, Taketani Y. The progesterone-responsive gene 14-3-3τ enhances the transcriptional activity of progesterone receptor in uterine cells. J Mol Endocrinol 2012; 49:193-202. [PMID: 22967481 DOI: 10.1530/jme-12-0112] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Members of the 14-3-3 family are intracellular dimeric phosphoserine-binding proteins that can associate with and modulate the activities of many proteins. In our efforts to isolate the genes regulated by progesterone (P(4)) using suppressive subtractive hybridization, we previously found that 14-3-3τ is one of the genes upregulated by P(4). In this study, we demonstrated by quantitative RT-PCR (qRT-PCR), western blot analyses, and immunohistochemistry that 14-3-3τ mRNA and protein levels were increased in the rat uterus after P(4) treatment. Furthermore, qRT-PCR indicated that P(4) increased 14-3-3τ mRNA levels in human endometrial epithelial cells and endometrial stromal cells (ESCs). Western blot and qRT-PCR analyses revealed that in vitro decidualization using cAMP and medroxyprogesterone 17-acetate increased levels of 14-3-3τ mRNA and protein in ESCs. We have shown by qRT-PCR and western blot analyses that P(4) increased the mRNA and protein levels of 14-3-3τ in Ishikawa cells that stably express P(4) receptor-B (PR-B). Immunocytochemistry revealed that 14-3-3τ colocalizes with PR and translocates from the cytoplasm to the nucleus in response to P(4). Moreover, by luciferase reporter assay, we demonstrated that 14-3-3τ enhances the transcriptional activity of PR-B. Taken together, we propose that 14-3-3τ is a P(4)-responsive gene in uterine cells that modulates P(4) signaling.
Collapse
Affiliation(s)
- Masanori Ito
- Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Murata T, Takayama KI, Urano T, Fujimura T, Ashikari D, Obinata D, Horie-Inoue K, Takahashi S, Ouchi Y, Homma Y, Inoue S. 14-3-3ζ, a novel androgen-responsive gene, is upregulated in prostate cancer and promotes prostate cancer cell proliferation and survival. Clin Cancer Res 2012; 18:5617-27. [PMID: 22904106 DOI: 10.1158/1078-0432.ccr-12-0281] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE Androgen receptor is an essential transcriptional factor that contributes to the development and progression of prostate cancer. In this study, we investigated the androgen regulation and functional analysis of 14-3-3ζ in prostate cancer. EXPERIMENTAL DESIGN Using chromatin immunoprecipitation (ChIP) combined with DNA microarray (ChIP-chip) analysis in LNCaP cells, we identified a functional androgen receptor-binding site in the downstream region of the 14-3-3ζ gene. Androgen regulation was examined by quantitative reverse transcription PCR and Western blot analysis. Prostate cancer cells stably expressing 14-3-3ζ and siRNA knockdown were used for functional analyses. We further examined 14-3-3ζ expression in clinical samples of prostate cancer by immunohistochemistry and quantitative reverse transcription PCR. RESULTS Androgen-dependent upregulation of 14-3-3ζ was validated at the mRNA and protein levels. The 14-3-3ζ gene is favorable for cancer-cell survival, as its ectopic expression in LNCaP cells contributes to cell proliferation and the acquired resistance to etoposide-induced apoptosis. 14-3-3ζ expression was associated with androgen receptor transcriptional activity and prostate-specific antigen (PSA) mRNA expression. Immunoprecipitation indicated that 14-3-3ζ was associated with androgen receptor in the nucleus. Clinicopathologic studies further support the relevance of 14-3-3ζ in prostate cancers, as its higher expression is associated with malignancy and lymph node metastasis. CONCLUSIONS 14-3-3ζ is a novel androgen-responsive gene that activates proliferation, cell survival, and androgen receptor transcriptional activity. 14-3-3ζ may facilitate the progression of prostate cancer.
Collapse
Affiliation(s)
- Taro Murata
- Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Godoy A, Kawinski E, Li Y, Oka D, Alexiev B, Azzouni F, Titus MA, Mohler JL. 5α-reductase type 3 expression in human benign and malignant tissues: a comparative analysis during prostate cancer progression. Prostate 2011; 71:1033-46. [PMID: 21557268 PMCID: PMC4295561 DOI: 10.1002/pros.21318] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 11/10/2010] [Indexed: 12/22/2022]
Abstract
BACKGROUND A third isozyme of human 5α-steroid reductase, 5α-reductase-3, was identified in prostate tissue at the mRNA level. However, the levels of 5α-reductase-3 protein expression and its cellular localization in human tissues remain unknown. METHODS A specific monoclonal antibody was developed, validated, and used to characterize for the first time the expression of 5α-reductase-3 protein in 18 benign and 26 malignant human tissue types using immunostaining analyses. RESULTS AND CONCLUSIONS In benign tissues, 5α-reductase-3 immunostaining was high in conventional androgen-regulated human tissues, such as skeletal muscle and prostate. However, high levels of expression also were observed in non-conventional androgen-regulated tissues, which suggest either multiples target tissues for androgens or different functions of 5α-reductase-3 among human tissues. In malignant tissues, 5α-reductase-3 immunostaining was ubiquitous but particularly over-expressed in some cancers compared to their benign counterparts, which suggests a potential role for 5α-reductase-3 as a biomarker of malignancy. In benign prostate, 5α-reductase-3 immunostaining was localized to basal epithelial cells, with no immunostaining observed in secretory/luminal epithelial cells. In high-grade prostatic intraepithelial neoplasia (HGPIN), 5α-reductase-3 immunostaining was localized in both basal epithelial cells and neoplastic epithelial cells characteristic of HGPIN. In androgen-stimulated and castration-recurrent prostate cancer (CaP), 5α-reductase-3 immunostaining was present in most epithelial cells and at similar levels, and at levels higher than observed in benign prostate. Analyses of expression and functionality of 5α-reductase-3 in human tissues may prove useful for development of treatment for benign prostatic enlargement and prevention and treatment of CaP.
Collapse
Affiliation(s)
- Alejandro Godoy
- Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Elzbieta Kawinski
- Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Yun Li
- Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Daizo Oka
- Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Borislav Alexiev
- Department of Pathology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Faris Azzouni
- Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Mark A. Titus
- Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - James L. Mohler
- Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263
- Department of Urology, University at Buffalo School of Medicine and Biotechnology, Buffalo, New York 14261
- Lineberger Comprehensive Cancer Center, University of North Carolina Schoolof Medicine, Chapel Hill, North Carolina 27599
- Department of Surgery, Division of Urology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
- Correspondence to: James L. Mohler, MD, Associate Director for Translational Research and Chair, Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263.
| |
Collapse
|
13
|
ERK/p90(RSK)/14-3-3 signalling has an impact on expression of PEA3 Ets transcription factors via the transcriptional repressor capicúa. Biochem J 2011; 433:515-25. [PMID: 21087211 PMCID: PMC3025492 DOI: 10.1042/bj20101562] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Compounds that inhibit signalling upstream of ERK (extracellular-signal-regulated kinase) are promising anticancer therapies, motivating research to define how this pathway promotes cancers. In the present study, we show that human capicúa represses mRNA expression for PEA3 (polyoma enhancer activator 3) Ets transcription factors ETV1, ETV4 and ETV5 (ETV is Ets translocation variant), and this repression is relieved by multisite controls of capicúa by ERK, p90RSK (p90 ribosomal S6 kinase) and 14-3-3 proteins. Specifically, 14-3-3 binds to p90RSK-phosphorylated Ser173 of capicúa thereby modulating DNA binding to its HMG (high-mobility group) box, whereas ERK phosphorylations prevent binding of a C-terminal NLS (nuclear localization sequence) to importin α4 (KPNA3). ETV1, ETV4 and ETV5 mRNA levels in melanoma cells are elevated by siRNA (small interfering RNA) knockdown of capicúa, and decreased by inhibiting ERK and/or expressing a form of capicúa that cannot bind to 14-3-3 proteins. Capicúa knockdown also enhances cell migration. The findings of the present study give further mechanistic insights into why ETV1 is highly expressed in certain cancers, indicate that loss of capicúa can desensitize cells to the effects of ERK pathway inhibitors, and highlight interconnections among growth factor signalling, spinocerebellar ataxias and cancers.
Collapse
|