1
|
Mizejewski GJ. The Role of Ion Channels and Chemokines in Cancer Growth and Metastasis: A Proposed Mode of Action Using Peptides in Cancer Therapy. Cancers (Basel) 2024; 16:1531. [PMID: 38672613 PMCID: PMC11048196 DOI: 10.3390/cancers16081531] [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: 01/22/2024] [Revised: 04/12/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Metastasis (Met) largely contributes to the major cause of cancer deaths throughout the world, rather than the growth of the tumor mass itself. The present report brings together several of the pertinent contributors to cancer growth and metastatic processes from an activity standpoint. Such biological activities include the following: (1) cell adherence and detachment; (2) cell-to-cell contact; (3) contact inhibition; (4) the cell interfacing with the extracellular matrix (ECM); (5) tumor cell-to-stroma communication networks; (6) chemotaxis; and (7) cell membrane potential. Moreover, additional biochemical factors that contribute to cancer growth and metastasis have been shown to comprise the following: (a) calcium levels in the extracellular matrix and in intracellular compartments; (b) cation voltage and ATP-regulated potassium channels; (c) selective and non-selective cation channels; and (d) chemokines (cytokines) and their receptors, such as CXCL12 (SDF-1) and its receptor/binding partner, CXCR4. These latter molecular components represent a promising group of an interacting and synchronized set of candidates ideal for peptide therapeutic targeting for cancer growth and metastasis. Such peptides can be obtained from naturally occurring proteins such as alpha-fetoprotein (AFP), an onco-fetal protein and clinical biomarker.
Collapse
Affiliation(s)
- Gerald J. Mizejewski
- Division of Translational Medicine, Molecular Diagnostics Laboratory, Albany, NY 12201, USA; ; Tel.: +518-486-5900; Fax: +518-402-5002
- Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201, USA
- Biggs Laboratory, Empire State Plaza, Albany, NY 12237, USA
| |
Collapse
|
2
|
Głowska-Ciemny J, Szymański M, Kuszerska A, Malewski Z, von Kaisenberg C, Kocyłowski R. The Role of Alpha-Fetoprotein (AFP) in Contemporary Oncology: The Path from a Diagnostic Biomarker to an Anticancer Drug. Int J Mol Sci 2023; 24:ijms24032539. [PMID: 36768863 PMCID: PMC9917199 DOI: 10.3390/ijms24032539] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/21/2023] [Accepted: 01/22/2023] [Indexed: 01/31/2023] Open
Abstract
This article presents contemporary opinion on the role of alpha-fetoprotein in oncologic diagnostics and treatment. This role stretches far beyond the already known one-that of the biomarker of hepatocellular carcinoma. The turn of the 20th and 21st centuries saw a significant increase in knowledge about the fundamental role of AFP in the neoplastic processes, and in the induction of features of malignance and drug resistance of hepatocellular carcinoma. The impact of AFP on the creation of an immunosuppressive environment for the developing tumor was identified, giving rise to attempts at immunotherapy. The paper presents current and prospective therapies using AFP and its derivatives and the gene therapy options. We directed our attention to both the benefits and risks associated with the use of AFP in oncologic therapy.
Collapse
Affiliation(s)
- Joanna Głowska-Ciemny
- PreMediCare New Med Medical Center, ul. Czarna Rola 21, 61-625 Poznań, Poland
- Correspondence: (J.G.-C.); (R.K.)
| | - Marcin Szymański
- PreMediCare New Med Medical Center, ul. Czarna Rola 21, 61-625 Poznań, Poland
| | - Agata Kuszerska
- PreMediCare New Med Medical Center, ul. Czarna Rola 21, 61-625 Poznań, Poland
| | - Zbyszko Malewski
- Department of Perinatology and Gynecology, Poznan University of Medical Sciences, 60-535 Poznań, Poland
| | - Constantin von Kaisenberg
- Department of Obstetrics and Gynecology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Rafał Kocyłowski
- PreMediCare New Med Medical Center, ul. Czarna Rola 21, 61-625 Poznań, Poland
- Correspondence: (J.G.-C.); (R.K.)
| |
Collapse
|
3
|
Abstract
In vitro systems capable of reconstituting the process of mouse oogenesis are now being established to help develop further understanding of the mechanisms underlying oocyte/follicle development and differentiation. These systems could also help increase the production of useful livestock or genetically modified animals, and aid in identifying the causes of infertility in humans. Recently, we revealed, using an in vitro system for recapitulating oogenesis, that the activation of the estrogen signaling pathway induces abnormal follicle formation, that blocking estrogen-induced expression of anti-Müllerian hormone is crucial for normal follicle formation, and that the production of α-fetoprotein in fetal liver tissue is involved in normal in vivo follicle formation. In mouse fetuses, follicle formation is not carried out by factors within the ovaries but is instead orchestrated by distal endocrine factors. This review outlines findings from genetics, endocrinology, and in vitro studies regarding the factors that can affect the formation of primordial follicles in mammals.
Collapse
|
4
|
Lin B, Dong X, Wang Q, Li W, Zhu M, Li M. AFP-Inhibiting Fragments for Drug Delivery: The Promise and Challenges of Targeting Therapeutics to Cancers. Front Cell Dev Biol 2021; 9:635476. [PMID: 33898423 PMCID: PMC8061420 DOI: 10.3389/fcell.2021.635476] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 03/12/2021] [Indexed: 01/08/2023] Open
Abstract
Alpha fetoprotein (AFP) plays a key role in stimulating the growth, metastasis and drug resistance of hepatocellular carcinoma (HCC). AFP is an important target molecule in the treatment of HCC. The application of AFP-derived peptides, AFP fragments and recombinant AFP (AFP-inhibiting fragments, AIFs) to inhibit the binding of AFP to intracellular proteins or its receptors is the basis of a new strategy for the treatment of HCC and other cancers. In addition, AIFs can be combined with drugs and delivery agents to target treatments to cancer. AIFs conjugated to anticancer drugs not only destroy cancer cells with these drugs but also activate immune cells to kill cancer cells. Furthermore, AIF delivery of drugs relieves immunosuppression and enhances chemotherapy effects. The synergism of immunotherapy and targeted chemotherapy is expected to play an important role in enhancing the treatment effect of patients with cancer. AIF delivery of drugs will be an available strategy for the targeted treatment of cancer in the future.
Collapse
Affiliation(s)
- Bo Lin
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Xu Dong
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Qiujiao Wang
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Wei Li
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Mingyue Zhu
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Mengsen Li
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China.,Institution of Tumor, Hainan Medical College, Haikou, China
| |
Collapse
|
5
|
Lin B, Wang Q, Liu K, Dong X, Zhu M, Li M. Alpha-Fetoprotein Binding Mucin and Scavenger Receptors: An Available Bio-Target for Treating Cancer. Front Oncol 2021; 11:625936. [PMID: 33718192 PMCID: PMC7947232 DOI: 10.3389/fonc.2021.625936] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 01/07/2021] [Indexed: 12/26/2022] Open
Abstract
Alpha-fetoprotein (AFP) entrance into cancer cells is mediated by AFP receptors (AFPRs) and exerts malignant effects. Therefore, understanding the structure of AFPRs will facilitate the development of rational approaches for vaccine design, drug delivery, antagonizing immune suppression and diagnostic imaging to treat cancer effectively. Throughout the last three decades, the identification of universal receptors for AFP has failed due to their complex carbohydrate polymer structures. Here, we focused on the two types of binding proteins or receptors that may serve as AFPRs, namely, the A) mucin receptors family, and B) the scavenger family. We presented an informative review with detailed descriptions of the signal transduction, cross-talk, and interplay of various transcription factors which highlight the downstream events following AFP binding to mucin or scavenger receptors. We mainly explored the underlying mechanisms involved mucin or scavenger receptors that interact with AFP, provide more evidence to support these receptors as tumor AFPRs, and establish a theoretical basis for targeting therapy of cancer.
Collapse
Affiliation(s)
- Bo Lin
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Qiujiao Wang
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Kun Liu
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Xu Dong
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Mingyue Zhu
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China
| | - Mengsen Li
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical College, Haikou, China.,Institution of Tumor, Hainan Medical College, Haikou, China
| |
Collapse
|
6
|
Moldogazieva NT, Ostroverkhova DS, Kuzmich NN, Kadochnikov VV, Terentiev AA, Porozov YB. Elucidating Binding Sites and Affinities of ERα Agonists and Antagonists to Human Alpha-Fetoprotein by In Silico Modeling and Point Mutagenesis. Int J Mol Sci 2020; 21:ijms21030893. [PMID: 32019136 PMCID: PMC7036865 DOI: 10.3390/ijms21030893] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/24/2020] [Accepted: 01/28/2020] [Indexed: 02/06/2023] Open
Abstract
Alpha-fetoprotein (AFP) is a major embryo- and tumor-associated protein capable of binding and transporting a variety of hydrophobic ligands, including estrogens. AFP has been shown to inhibit estrogen receptor (ER)-positive tumor growth, which can be attributed to its estrogen-binding ability. Despite AFP having long been investigated, its three-dimensional (3D) structure has not been experimentally resolved and molecular mechanisms underlying AFP–ligand interaction remains obscure. In our study, we constructed a homology-based 3D model of human AFP (HAFP) with the purpose of molecular docking of ERα ligands, three agonists (17β-estradiol, estrone and diethylstilbestrol), and three antagonists (tamoxifen, afimoxifene and endoxifen) into the obtained structure. Based on the ligand-docked scoring functions, we identified three putative estrogen- and antiestrogen-binding sites with different ligand binding affinities. Two high-affinity binding sites were located (i) in a tunnel formed within HAFP subdomains IB and IIA and (ii) on the opposite side of the molecule in a groove originating from a cavity formed between domains I and III, while (iii) the third low-affinity binding site was found at the bottom of the cavity. Here, 100 ns molecular dynamics (MD) simulation allowed us to study their geometries and showed that HAFP–estrogen interactions were caused by van der Waals forces, while both hydrophobic and electrostatic interactions were almost equally involved in HAFP–antiestrogen binding. Molecular mechanics/Generalized Born surface area (MM/GBSA) rescoring method exploited for estimation of binding free energies (ΔGbind) showed that antiestrogens have higher affinities to HAFP as compared to estrogens. We performed in silico point substitutions of amino acid residues to confirm their roles in HAFP–ligand interactions and showed that Thr132, Leu138, His170, Phe172, Ser217, Gln221, His266, His316, Lys453, and Asp478 residues, along with two disulfide bonds (Cys224–Cys270 and Cys269–Cys277), have key roles in both HAFP–estrogen and HAFP–antiestrogen binding. Data obtained in our study contribute to understanding mechanisms underlying protein–ligand interactions and anticancer therapy strategies based on ERα-binding ligands.
Collapse
Affiliation(s)
- Nurbubu T. Moldogazieva
- Laboratory of Bioinformatics, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia; (D.S.O.); (N.N.K.); (Y.B.P.)
- Correspondence:
| | - Daria S. Ostroverkhova
- Laboratory of Bioinformatics, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia; (D.S.O.); (N.N.K.); (Y.B.P.)
- Department of Bioengineering, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Nikolai N. Kuzmich
- Laboratory of Bioinformatics, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia; (D.S.O.); (N.N.K.); (Y.B.P.)
- Department of Drug Safety, I.M. Smorodintsev Research Institute of Influenza, WHO National Influenza Centre of Russia, 197376 Saint Petersburg, Russia
| | - Vladimir V. Kadochnikov
- Department of Food Biotechnology and Engineering, Saint Petersburg National Research University of Information Technologies, Mechanics and Optics, 197101 Saint-Petersburg, Russia;
| | - Alexander A. Terentiev
- Deparment of Biochemistry and Molecular Biology, N.I. Pirogov Russian National Research Medical University, 117997 Moscow, Russia;
| | - Yuri B. Porozov
- Laboratory of Bioinformatics, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia; (D.S.O.); (N.N.K.); (Y.B.P.)
- Department of Food Biotechnology and Engineering, Saint Petersburg National Research University of Information Technologies, Mechanics and Optics, 197101 Saint-Petersburg, Russia;
| |
Collapse
|
7
|
Brown AM, Miranda-Alarćon YS, Knoll GA, Santora AM, Banerjee IA. Fetoprotein Derived Short Peptide Coated Nanostructured Amphiphilic Surfaces for Targeting Mouse Breast Cancer Cells. INTERNATIONAL JOURNAL OF NANOSCIENCE 2017. [DOI: 10.1142/s0219581x1650023x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this work, self-assembled tumor targeting nanostructured surfaces were developed from a newly designed amphiphile by conjugating boc protected isoleucine with 2,[Formula: see text] ethylenedioxy bis ethylamine (IED). To target mouse mammary tumor cells, a short peptide sequence derived from the human alpha-fetoprotein (AFP), LSEDKLLACGEG was attached to the self-assembled nanostructures. Tumor targeting and cell proliferation were examined in the presence of nanoscale assemblies. To further obliterate mouse breast tumor cells, the chemotherapeutic drug tamoxifen was then entrapped into the nanoassemblies. Our studies indicated that the targeting systems were able to efficiently encapsulate and release tamoxifen. Cell proliferation studies showed that IED-AFP peptide loaded with tamoxifen decreased the proliferation of breast cancer cells while in the presence of the IED-AFP peptide nanoassemblies alone, the growth was relatively slower. In the presence of human dermal fibroblasts however cell proliferation continued similar to controls. Furthermore, the nanoscale assemblies were found to induce apoptosis in mouse breast cancer cells. To examine live binding interactions, SPR analysis revealed that tamoxifen encapsulated IED-AFP peptide nanoassemblies bound to the breast cancer cells more efficiently compared to unencapsulated assemblies. Thus, we have developed nanoscale assemblies that can specifically bind to and target tumor cells, with increased toxicity in the presence of a chemotherapeutic drug.
Collapse
Affiliation(s)
- Alexandra M. Brown
- Department of Chemistry Fordham University, 441 E. Fordham Road, Bronx, NY 10458, USA
| | | | - Grant A. Knoll
- Department of Chemistry Fordham University, 441 E. Fordham Road, Bronx, NY 10458, USA
| | - Anthony M. Santora
- Department of Chemistry Fordham University, 441 E. Fordham Road, Bronx, NY 10458, USA
| | - Ipsita A. Banerjee
- Department of Chemistry Fordham University, 441 E. Fordham Road, Bronx, NY 10458, USA
| |
Collapse
|
8
|
The alpha-fetoprotein (AFP) third domain: a search for AFP interaction sites of cell cycle proteins. Tumour Biol 2016; 37:12697-12711. [DOI: 10.1007/s13277-016-5131-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/29/2016] [Indexed: 01/28/2023] Open
|
9
|
Mizejewski GJ. The alpha-fetoprotein third domain receptor binding fragment: in search of scavenger and associated receptor targets. J Drug Target 2015; 23:538-51. [DOI: 10.3109/1061186x.2015.1015538] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
10
|
The adenocarcinoma cell surface mucin receptor for alpha-fetoprotein: is the same receptor present on circulating monocytes and macrophages? A commentary. Tumour Biol 2014; 35:7397-402. [PMID: 24916573 DOI: 10.1007/s13277-014-2183-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/02/2014] [Indexed: 12/11/2022] Open
Abstract
The mucin family of proteins is largely expressed on sedentary epithelial cells lining the gastrointestinal, pulmonary, and reproductive tracts and their associated organs and malignant tumors. It is less well-known that mucins are also expressed on circulatory cells of the immune and inflammatory systems, such as monocytes, macrophages, leukemic, and lymphoma cells. The epithelial mucins function in (a) protection and lubrication of mucosal linings, (b) cell adhesion and cell-to-cell contact, (c) cell migration and metastasis, and (d) signal transduction. It would be logical to presume that mucins expressed on circulating mononuclear cells could perform similar functions. Recently, it was proposed that the alpha-fetoprotein (AFP) receptor, known to be present on solid epithelial-derived malignant tumor cells, can be identified as a mucin glycoprotein. Interestingly, it was also reported that AFP binds to a receptor on circulating cells and sedentary tumor cells of lymphoreticular origin, especially monocytes associated with lymphomas and leukemias. The primary objective of the present commentary is to present literature-based evidence that some of the cell surface mucins on sedentary epithelial tumor cells and certain mucins expressed on circulating monocytes/macrophages are identical to the AFP receptor. The secondary objective is to discuss the role of AFP and its derived peptides in the growth suppression of adenocarcinomas and lymphomas using the AFP-mucin receptor concept as a key to the mechanism of tumor growth inhibition.
Collapse
|
11
|
Temelso B, Alser KA, Gauthier A, Palmer AK, Shields GC. Structural Analysis of α-Fetoprotein (AFP)-like Peptides with Anti-Breast-Cancer Properties. J Phys Chem B 2014; 118:4514-26. [DOI: 10.1021/jp500017b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Berhane Temelso
- Dean’s
Office, College of Arts and Sciences, and Department of Chemistry, Bucknell University, Lewisburg, Pennsylvania 17837, United States
- Dean’s Office, College of Science and Technology, and Department of Chemistry & Physics, Armstrong Atlantic State University, 11935 Abercorn Street, Savannah, Georgia 31419, United States
| | - Katherine A. Alser
- Dean’s
Office, College of Arts and Sciences, and Department of Chemistry, Bucknell University, Lewisburg, Pennsylvania 17837, United States
| | - Arianne Gauthier
- Dean’s Office, College of Science and Technology, and Department of Chemistry & Physics, Armstrong Atlantic State University, 11935 Abercorn Street, Savannah, Georgia 31419, United States
| | - Amber Kay Palmer
- Dean’s Office, College of Science and Technology, and Department of Chemistry & Physics, Armstrong Atlantic State University, 11935 Abercorn Street, Savannah, Georgia 31419, United States
| | - George C. Shields
- Dean’s
Office, College of Arts and Sciences, and Department of Chemistry, Bucknell University, Lewisburg, Pennsylvania 17837, United States
- Dean’s Office, College of Science and Technology, and Department of Chemistry & Physics, Armstrong Atlantic State University, 11935 Abercorn Street, Savannah, Georgia 31419, United States
| |
Collapse
|
12
|
Mizejewski GJ. Review of the adenocarcinoma cell surface receptor for human alpha-fetoprotein; proposed identification of a widespread mucin as the tumor cell receptor. Tumour Biol 2013; 34:1317-36. [PMID: 23446764 DOI: 10.1007/s13277-013-0704-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 02/10/2013] [Indexed: 02/06/2023] Open
Abstract
The identification of a tumor cell receptor for alpha-fetoprotein (AFP) has long been sought in the field of medicine. The uptake and endocytosis of AFP by rat tumor cells in 1983 sparked a series of confirmatory reports which were extended to include multiple tumor types in rats, mice, and humans. The following year, French investigators characterized the binding properties of the AFP receptor but they did not purify and characterize the receptor. It was not until 1991-1992 that an AFP receptor was partially purified and characterized from both human monocytes and breast cancer cells. By 1993, monoclonal antibodies had been raised against the "AFP receptor" derived from breast cancer extracts with claims that the receptor was a widespread oncoprotein biomarker for cancer. To date, that receptor has yet to be identified due to its complex multimeric structure and carbohydrate composition. The present report will review the literature of the multiple AFP receptors previously including their cellular uptake, transmembrane passage, and partial biochemical characterization. . In addition, evidence derived from computer modeling, proteolytic/fragmentation cleavage patterns, domain structure analysis, and protein binding software analysis will be presented in a proposed identification of a widespread protein/gene family of transmembrane proteins which fits many, if not most, of the criteria attributed to the AFP receptor. The proposed receptor protein family is tentatively identified as an epithelial cell surface mucin constituting one (or more) of many classes of single-pass transmembrane proteins. Present data do not support the concept that the AFP receptor is a "universal" tumor receptor and/or biomarker, but rather a widespread mucin protein that functions primarily in protecting and lubricating epithelial mucosal layers, and engaging in signal transduction; the mucin only binds AFP as a molecule serving in a subordinate or ancillary function.
Collapse
Affiliation(s)
- G J Mizejewski
- Wadsworth Center, Division of Translational Medicine, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA.
| |
Collapse
|