1
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Márquez-López A, Fanarraga ML. AB Toxins as High-Affinity Ligands for Cell Targeting in Cancer Therapy. Int J Mol Sci 2023; 24:11227. [PMID: 37446406 DOI: 10.3390/ijms241311227] [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: 05/15/2023] [Revised: 06/30/2023] [Accepted: 07/06/2023] [Indexed: 07/15/2023] Open
Abstract
Conventional targeted therapies for the treatment of cancer have limitations, including the development of acquired resistance. However, novel alternatives have emerged in the form of targeted therapies based on AB toxins. These biotoxins are a diverse group of highly poisonous molecules that show a nanomolar affinity for their target cell receptors, making them an invaluable source of ligands for biomedical applications. Bacterial AB toxins, in particular, are modular proteins that can be genetically engineered to develop high-affinity therapeutic compounds. These toxins consist of two distinct domains: a catalytically active domain and an innocuous domain that acts as a ligand, directing the catalytic domain to the target cells. Interestingly, many tumor cells show receptors on the surface that are recognized by AB toxins, making these high-affinity proteins promising tools for developing new methods for targeting anticancer therapies. Here we describe the structure and mechanisms of action of Diphtheria (Dtx), Anthrax (Atx), Shiga (Stx), and Cholera (Ctx) toxins, and review the potential uses of AB toxins in cancer therapy. We also discuss the main advances in this field, some successful results, and, finally, the possible development of innovative and precise applications in oncology based on engineered recombinant AB toxins.
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Affiliation(s)
- Ana Márquez-López
- The Nanomedicine Group, Institute Valdecilla-IDIVAL, 39011 Santander, Spain
| | - Mónica L Fanarraga
- The Nanomedicine Group, Institute Valdecilla-IDIVAL, 39011 Santander, Spain
- Molecular Biology Department, Faculty of Medicine, Universidad de Cantabria, 39011 Santander, Spain
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2
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Kim HS, Bae JH, Kim G, Song JJ, Kim HS. Construction and Functionalization of a Clathrin Assembly for a Targeted Protein Delivery. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2204620. [PMID: 36456203 DOI: 10.1002/smll.202204620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 11/02/2022] [Indexed: 06/17/2023]
Abstract
Protein assemblies have drawn much attention as platforms for biomedical applications, including gene/drug delivery and vaccine, due to biocompatibility and functional diversity. Here, the construction and functionalization of a protein assembly composed of human clathrin heavy chain and light chain for a targeted protein delivery, is presented. The clathrin heavy and light chains are redesigned and associated with each other, and the resulting triskelion unit further self-assembled into a clathrin assembly with the size of about 28 nm in diameter. The clathrin assembly is dual-functionalized with a protein cargo and a targeting moiety using two different orthogonal protein-ligand pairs through one-pot reaction. The functionalized clathrin assembly exhibits about a 900-fold decreased KD value for a cell-surface target due to avidity compared to a native targeting moiety. The utility of the clathrin assembly is demonstrated by an efficient delivery of a protein cargo into tumor cells in a target-specific manner, resulting in a strong cytotoxic effect. The present approach can be used in the creation of protein assemblies with multimodality.
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Affiliation(s)
- Hong-Sik Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Jin-Ho Bae
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Gijeong Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Ji-Joon Song
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Hak-Sung Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
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3
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Tian S, Liu Y, Appleton E, Wang H, Church GM, Dong M. Targeted intracellular delivery of Cas13 and Cas9 nucleases using bacterial toxin-based platforms. Cell Rep 2022; 38:110476. [PMID: 35263584 PMCID: PMC8958846 DOI: 10.1016/j.celrep.2022.110476] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 12/26/2021] [Accepted: 02/11/2022] [Indexed: 02/06/2023] Open
Abstract
Targeted delivery of therapeutic proteins toward specific cells and across cell membranes remains major challenges. Here, we develop protein-based delivery systems utilizing detoxified single-chain bacterial toxins such as diphtheria toxin (DT) and botulinum neurotoxin (BoNT)-like toxin, BoNT/X, as carriers. The system can deliver large protein cargoes including Cas13a, CasRx, Cas9, and Cre recombinase into cells in a receptor-dependent manner, although delivery of ribonucleoproteins containing guide RNAs is not successful. Delivery of Cas13a and CasRx, together with guide RNA expression, reduces mRNAs encoding GFP, SARS-CoV-2 fragments, and endogenous proteins PPIB, KRAS, and CXCR4 in multiple cell lines. Delivery of Cre recombinase modifies the reporter loci in cells. Delivery of Cas9, together with guide RNA expression, generates mutations at the targeted genomic sites in cell lines and induced pluripotent stem cell (iPSC)-derived human neurons. These findings establish modular delivery systems based on single-chain bacterial toxins for delivery of membrane-impermeable therapeutics into targeted cells.
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Affiliation(s)
- Songhai Tian
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA.
| | - Yang Liu
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Nephrology, The First Hospital of Jilin University, Changchun, 130021, China
| | - Evan Appleton
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA 02115, USA
| | - Huan Wang
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - George M Church
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA 02115, USA
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA.
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4
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The Cytotoxic Necrotizing Factors (CNFs)-A Family of Rho GTPase-Activating Bacterial Exotoxins. Toxins (Basel) 2021; 13:toxins13120901. [PMID: 34941738 PMCID: PMC8709095 DOI: 10.3390/toxins13120901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 11/29/2021] [Accepted: 12/01/2021] [Indexed: 11/17/2022] Open
Abstract
The cytotoxic necrotizing factors (CNFs) are a family of Rho GTPase-activating single-chain exotoxins that are produced by several Gram-negative pathogenic bacteria. Due to the pleiotropic activities of the targeted Rho GTPases, the CNFs trigger multiple signaling pathways and host cell processes with diverse functional consequences. They influence cytokinesis, tissue integrity, cell barriers, and cell death, as well as the induction of inflammatory and immune cell responses. This has an enormous influence on host-pathogen interactions and the severity of the infection. The present review provides a comprehensive insight into our current knowledge of the modular structure, cell entry mechanisms, and the mode of action of this class of toxins, and describes their influence on the cell, tissue/organ, and systems levels. In addition to their toxic functions, possibilities for their use as drug delivery tool and for therapeutic applications against important illnesses, including nervous system diseases and cancer, have also been identified and are discussed.
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Bae J, Kim H, Kim G, Song J, Kim H. Dendrimer-Like Supramolecular Assembly of Proteins with a Tunable Size and Valency Through Stepwise Iterative Growth. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2102991. [PMID: 34719882 PMCID: PMC8693032 DOI: 10.1002/advs.202102991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/15/2021] [Indexed: 06/13/2023]
Abstract
The assembly of proteins in a programmable manner provides insight into the creation of novel functional nanomaterials for practical applications. Despite many advances, however, a rational protein assembly with an easy scalability in terms of size and valency remains a challenge. Here, a simple bottom-up approach to the supramolecular protein assembly with a tunable size and valency in a programmable manner is presented. The dendrimer-like protein assembly, simply called a "protein dendrimer," is constructed through a stepwise and alternate addition of a building block protein. Starting from zeroth-generation protein dendrimer (pG0 ) of 27 kDa, the protein dendrimer is sequentially grown to pG1 , pG2 , pG3 , to pG4 with a molecular mass of 94, 216, 483, and 959 kDa, respectively. The valency of the protein dendrimers at the periphery increases by a factor of two after each generation, allowing a tunable valency and easy functionalization. The protein dendrimers functionalizes with a targeting moiety and a cytotoxic protein cargo shows a typical feature of multi-valency in the avidity and a highly enhanced cellular cytotoxicity, exemplifying their utility as a protein delivery platform. The present approach can be effectively used in the creation of protein architectures with new functions for biotechnological and medical applications.
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Affiliation(s)
- Jin‐Ho Bae
- Department of Biological SciencesKorea Advanced Institute of Science and Technology (KAIST)Daejeon34141Korea
- Present address:
ProEn TherapeuticsSeongnam‐si13105Korea
| | - Hong‐Sik Kim
- Department of Biological SciencesKorea Advanced Institute of Science and Technology (KAIST)Daejeon34141Korea
| | - Gijeong Kim
- Department of Biological SciencesKorea Advanced Institute of Science and Technology (KAIST)Daejeon34141Korea
| | - Ji‐Joon Song
- Department of Biological SciencesKorea Advanced Institute of Science and Technology (KAIST)Daejeon34141Korea
| | - Hak‐Sung Kim
- Department of Biological SciencesKorea Advanced Institute of Science and Technology (KAIST)Daejeon34141Korea
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Shiga Toxins as Antitumor Tools. Toxins (Basel) 2021; 13:toxins13100690. [PMID: 34678982 PMCID: PMC8538568 DOI: 10.3390/toxins13100690] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/12/2021] [Accepted: 09/22/2021] [Indexed: 11/16/2022] Open
Abstract
Shiga toxins (Stxs), also known as Shiga-like toxins (SLT) or verotoxins (VT), constitute a family of structurally and functionally related cytotoxic proteins produced by the enteric pathogens Shigella dysenteriae type 1 and Stx-producing Escherichia coli (STEC). Infection with these bacteria causes bloody diarrhea and other pathological manifestations that can lead to HUS (hemolytic and uremic syndrome). At the cellular level, Stxs bind to the cellular receptor Gb3 and inhibit protein synthesis by removing an adenine from the 28S rRNA. This triggers multiple cellular signaling pathways, including the ribotoxic stress response (RSR), unfolded protein response (UPR), autophagy and apoptosis. Stxs cause several pathologies of major public health concern, but their specific targeting of host cells and efficient delivery to the cytosol could potentially be exploited for biomedical purposes. Moreover, high levels of expression have been reported for the Stxs receptor, Gb3/CD77, in Burkitt's lymphoma (BL) cells and on various types of solid tumors. These properties have led to many attempts to develop Stxs as tools for biomedical applications, such as cancer treatment or imaging, and several engineered Stxs are currently being tested. We provide here an overview of these studies.
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7
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Lingwood C. Therapeutic Uses of Bacterial Subunit Toxins. Toxins (Basel) 2021; 13:toxins13060378. [PMID: 34073185 PMCID: PMC8226680 DOI: 10.3390/toxins13060378] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/17/2021] [Accepted: 05/18/2021] [Indexed: 02/07/2023] Open
Abstract
The B subunit pentamer verotoxin (VT aka Shiga toxin-Stx) binding to its cellular glycosphingolipid (GSL) receptor, globotriaosyl ceramide (Gb3) mediates internalization and the subsequent receptor mediated retrograde intracellular traffic of the AB5 subunit holotoxin to the endoplasmic reticulum. Subunit separation and cytosolic A subunit transit via the ER retrotranslocon as a misfolded protein mimic, then inhibits protein synthesis to kill cells, which can cause hemolytic uremic syndrome clinically. This represents one of the most studied systems of prokaryotic hijacking of eukaryotic biology. Similarly, the interaction of cholera AB5 toxin with its GSL receptor, GM1 ganglioside, is the key component of the gastrointestinal pathogenesis of cholera and follows the same retrograde transport pathway for A subunit cytosol access. Although both VT and CT are the cause of major pathology worldwide, the toxin–receptor interaction is itself being manipulated to generate new approaches to control, rather than cause, disease. This arena comprises two areas: anti neoplasia, and protein misfolding diseases. CT/CTB subunit immunomodulatory function and anti-cancer toxin immunoconjugates will not be considered here. In the verotoxin case, it is clear that Gb3 (and VT targeting) is upregulated in many human cancers and that there is a relationship between GSL expression and cancer drug resistance. While both verotoxin and cholera toxin similarly hijack the intracellular ERAD quality control system of nascent protein folding, the more widespread cell expression of GM1 makes cholera the toxin of choice as the means to more widely utilise ERAD targeting to ameliorate genetic diseases of protein misfolding. Gb3 is primarily expressed in human renal tissue. Glomerular endothelial cells are the primary VT target but Gb3 is expressed in other endothelial beds, notably brain endothelial cells which can mediate the encephalopathy primarily associated with VT2-producing E. coli infection. The Gb3 levels can be regulated by cytokines released during EHEC infection, which complicate pathogenesis. Significantly Gb3 is upregulated in the neovasculature of many tumours, irrespective of tumour Gb3 status. Gb3 is markedly increased in pancreatic, ovarian, breast, testicular, renal, astrocytic, gastric, colorectal, cervical, sarcoma and meningeal cancer relative to the normal tissue. VT has been shown to be effective in mouse xenograft models of renal, astrocytoma, ovarian, colorectal, meningioma, and breast cancer. These studies are herein reviewed. Both CT and VT (and several other bacterial toxins) access the cell cytosol via cell surface ->ER transport. Once in the ER they interface with the protein folding homeostatic quality control pathway of the cell -ERAD, (ER associated degradation), which ensures that only correctly folded nascent proteins are allowed to progress to their cellular destinations. Misfolded proteins are translocated through the ER membrane and degraded by cytosolic proteosome. VT and CT A subunits have a C terminal misfolded protein mimic sequence to hijack this transporter to enter the cytosol. This interface between exogenous toxin and genetically encoded endogenous mutant misfolded proteins, provides a new therapeutic basis for the treatment of such genetic diseases, e.g., Cystic fibrosis, Gaucher disease, Krabbe disease, Fabry disease, Tay-Sachs disease and many more. Studies showing the efficacy of this approach in animal models of such diseases are presented.
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Affiliation(s)
- Clifford Lingwood
- Division of Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada;
- Departments of Laboratory Medicine & Pathobiology, and Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
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8
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Shilova O, Shramova E, Proshkina G, Deyev S. Natural and Designed Toxins for Precise Therapy: Modern Approaches in Experimental Oncology. Int J Mol Sci 2021; 22:ijms22094975. [PMID: 34067057 PMCID: PMC8124712 DOI: 10.3390/ijms22094975] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 04/29/2021] [Accepted: 05/05/2021] [Indexed: 02/08/2023] Open
Abstract
Cancer cells frequently overexpress specific surface receptors providing tumor growth and survival which can be used for precise therapy. Targeting cancer cell receptors with protein toxins is an attractive approach widely used in contemporary experimental oncology and preclinical studies. Methods of targeted delivery of toxins to cancer cells, different drug carriers based on nanosized materials (liposomes, nanoparticles, polymers), the most promising designed light-activated toxins, as well as mechanisms of the cytotoxic action of the main natural toxins used in modern experimental oncology, are discussed in this review. The prospects of the combined therapy of tumors based on multimodal nanostructures are also discussed.
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Affiliation(s)
- Olga Shilova
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry RAS, 117997 Moscow, Russia; (E.S.); (G.P.)
- Correspondence: (O.S.); (S.D.)
| | - Elena Shramova
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry RAS, 117997 Moscow, Russia; (E.S.); (G.P.)
| | - Galina Proshkina
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry RAS, 117997 Moscow, Russia; (E.S.); (G.P.)
| | - Sergey Deyev
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry RAS, 117997 Moscow, Russia; (E.S.); (G.P.)
- Center of Biomedical Engineering, Sechenov University, 119991 Moscow, Russia
- Research Centrum for Oncotheranostics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia
- Correspondence: (O.S.); (S.D.)
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9
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Liu Y, Tian S, Thaker H, Dong M. Shiga Toxins: An Update on Host Factors and Biomedical Applications. Toxins (Basel) 2021; 13:222. [PMID: 33803852 PMCID: PMC8003205 DOI: 10.3390/toxins13030222] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/13/2021] [Accepted: 03/15/2021] [Indexed: 12/18/2022] Open
Abstract
Shiga toxins (Stxs) are classic bacterial toxins and major virulence factors of toxigenic Shigella dysenteriae and enterohemorrhagic Escherichia coli (EHEC). These toxins recognize a glycosphingolipid globotriaosylceramide (Gb3/CD77) as their receptor and inhibit protein synthesis in cells by cleaving 28S ribosomal RNA. They are the major cause of life-threatening complications such as hemolytic uremic syndrome (HUS), associated with severe cases of EHEC infection, which is the leading cause of acute kidney injury in children. The threat of Stxs is exacerbated by the lack of toxin inhibitors and effective treatment for HUS. Here, we briefly summarize the Stx structure, subtypes, in vitro and in vivo models, Gb3 expression and HUS, and then introduce recent studies using CRISPR-Cas9-mediated genome-wide screens to identify the host cell factors required for Stx action. We also summarize the latest progress in utilizing and engineering Stx components for biomedical applications.
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Affiliation(s)
- Yang Liu
- Department of Nephrology, The First Hospital of Jilin University, Changchun 130021, China
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Songhai Tian
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Hatim Thaker
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Min Dong
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
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10
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Chen YA, Lai YR, Wu HY, Lo YJ, Chang YF, Hung CL, Lin CJ, Lo UG, Lin H, Hsieh JT, Chiu CH, Lin YH, Lai CH. Bacterial Genotoxin-Coated Nanoparticles for Radiotherapy Sensitization in Prostate Cancer. Biomedicines 2021; 9:biomedicines9020151. [PMID: 33557143 PMCID: PMC7913852 DOI: 10.3390/biomedicines9020151] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/17/2021] [Accepted: 01/20/2021] [Indexed: 12/25/2022] Open
Abstract
Prostate cancer (PCa) is one of the most commonly diagnosed cancers in men and usually becomes refractory because of recurrence and metastasis. CD44, a transmembrane glycoprotein, serves as a receptor for hyaluronic acid (HA). It has been found to be abundantly expressed in cancer stem cells (CSCs) that often exhibit a radioresistant phenotype. Cytolethal distending toxin (CDT), produced by Campylobacter jejuni, is a tripartite genotoxin composed of CdtA, CdtB, and CdtC subunits. Among the three, CdtB acts as a type I deoxyribonuclease (DNase I), which creates DNA double-strand breaks (DSBs). Nanoparticles loaded with antitumor drugs and specific ligands that recognize cancerous cell receptors are promising methods to overcome the therapeutic challenges. In this study, HA-decorated nanoparticle-encapsulated CdtB (HA-CdtB-NPs) were prepared and their targeted therapeutic activity in radioresistant PCa cells was evaluated. Our results showed that HA-CdtB-NPs sensitized radioresistant PCa cells by enhancing DSB and causing G2/M cell-cycle arrest, without affecting the normal prostate epithelial cells. HA-CdtB-NPs possess maximum target specificity and delivery efficiency of CdtB into the nucleus and enhance the effect of radiation in radioresistant PCa cells. These findings demonstrate that HA-CdtB-NPs exert target specificity accompanied with radiomimetic activity and can be developed as an effective strategy against radioresistant PCa.
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Affiliation(s)
- Yu-An Chen
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 33302, Taiwan; (Y.-A.C.); (Y.-R.L.); (H.-Y.W.); (Y.-J.L.); (Y.-F.C.)
- Department of Life Sciences, National Chung Hsing University, Taichung 40227, Taiwan;
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; (C.-J.L.); (U.-G.L.); (J.-T.H.)
| | - Yi-Ru Lai
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 33302, Taiwan; (Y.-A.C.); (Y.-R.L.); (H.-Y.W.); (Y.-J.L.); (Y.-F.C.)
| | - Hui-Yu Wu
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 33302, Taiwan; (Y.-A.C.); (Y.-R.L.); (H.-Y.W.); (Y.-J.L.); (Y.-F.C.)
| | - Yen-Ju Lo
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 33302, Taiwan; (Y.-A.C.); (Y.-R.L.); (H.-Y.W.); (Y.-J.L.); (Y.-F.C.)
| | - Yu-Fang Chang
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 33302, Taiwan; (Y.-A.C.); (Y.-R.L.); (H.-Y.W.); (Y.-J.L.); (Y.-F.C.)
| | - Chiu-Lien Hung
- Targeted Drug and Delivery Technology Division, Biomedical Technology and Device Research Laboratories, Industrial Technology Research Institute, Hsinchu 30011, Taiwan;
| | - Chun-Jung Lin
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; (C.-J.L.); (U.-G.L.); (J.-T.H.)
| | - U-Ging Lo
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; (C.-J.L.); (U.-G.L.); (J.-T.H.)
| | - Ho Lin
- Department of Life Sciences, National Chung Hsing University, Taichung 40227, Taiwan;
| | - Jer-Tsong Hsieh
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; (C.-J.L.); (U.-G.L.); (J.-T.H.)
- Department of Medical Research, School of Medicine, China Medical University and Hospital, Taichung 40447, Taiwan
| | - Cheng-Hsun Chiu
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 33302, Taiwan; (Y.-A.C.); (Y.-R.L.); (H.-Y.W.); (Y.-J.L.); (Y.-F.C.)
- Molecular Infectious Disease Research Center, Department of Pediatrics, Chang Gung Memorial Hospital, Linkou 33305, Taiwan
- Correspondence: (C.-H.C.); (Y.-H.L.); (C.-H.L.)
| | - Yu-Hsin Lin
- Department of Medical Research, School of Medicine, China Medical University and Hospital, Taichung 40447, Taiwan
- Center for Advanced Pharmaceutics and Drug Delivery Research, Department and Institute of Pharmacology, Institute of Biopharmaceutical Sciences, Faculty of Pharmacy, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
- Correspondence: (C.-H.C.); (Y.-H.L.); (C.-H.L.)
| | - Chih-Ho Lai
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan 33302, Taiwan; (Y.-A.C.); (Y.-R.L.); (H.-Y.W.); (Y.-J.L.); (Y.-F.C.)
- Department of Medical Research, School of Medicine, China Medical University and Hospital, Taichung 40447, Taiwan
- Molecular Infectious Disease Research Center, Department of Pediatrics, Chang Gung Memorial Hospital, Linkou 33305, Taiwan
- Department of Nursing, Asia University, Taichung 41354, Taiwan
- Correspondence: (C.-H.C.); (Y.-H.L.); (C.-H.L.)
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11
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Encarnação JC, Napolitano V, Opassi G, Danielson UH, Dubin G, Popowicz GM, Munier-Lehmann H, Buijs J, Andersson K, Björkelund H. A real-time cell-binding assay reveals dynamic features of STxB-Gb3 cointernalization and STxB-mediated cargo delivery into cancer cells. FEBS Lett 2020; 594:2406-2420. [PMID: 32473599 DOI: 10.1002/1873-3468.13847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/16/2020] [Accepted: 05/19/2020] [Indexed: 12/17/2022]
Abstract
The interaction between the Shiga toxin B-subunit (STxB) and its globotriaosylceramide receptor (Gb3) has a high potential for being exploited for targeted cancer therapy. The primary goal of this study was to evaluate the capacity of STxB to carry small molecules and proteins as cargo into cells. For this purpose, an assay was designed to provide real-time information about the StxB-Gb3 interaction as well as the dynamics and mechanism of the internalization process. The assay revealed the ability to distinguish the process of binding to the cell surface from internalization and presented the importance of receptor and STxB clustering for internalization. The overall setup demonstrated that the binding mechanism is complex, and the concept of affinity is difficult to apply. Hence, time-resolved methods, providing detailed information about the interaction of STxB with cells, are critical for the optimization of intracellular delivery.
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Affiliation(s)
- João Crispim Encarnação
- Ridgeview Instruments AB, Uppsala, Sweden.,Department of Immunology, Pathology and Genetics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Valeria Napolitano
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.,Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Giulia Opassi
- Department of Chemistry-BMC, Uppsala University, Uppsala, Sweden
| | | | - Grzegorz Dubin
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Grzegorz M Popowicz
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany.,Center for Integrated Protein Science Munich at Chair of Biomolecular NMR, Department Chemie, Technische Universität München, Garching, Germany
| | - Hélène Munier-Lehmann
- Unité de Chimie et Biocatalyse, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR3523, Paris, France
| | - Jos Buijs
- Ridgeview Instruments AB, Uppsala, Sweden.,Department of Immunology, Pathology and Genetics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Karl Andersson
- Ridgeview Instruments AB, Uppsala, Sweden.,Department of Immunology, Pathology and Genetics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
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12
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Sohn YK, Kim HS. Targeted delivery of a human Bcl-2-specific protein binder effectively induces apoptosis of cancer cells. Biochem Biophys Res Commun 2020; 526:447-452. [PMID: 32228885 DOI: 10.1016/j.bbrc.2020.03.113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 03/20/2020] [Indexed: 01/02/2023]
Abstract
Bcl-2 family proteins are critical switches to control cell death and survival, and Bcl-2 is a key regulator in pro-survival signaling, causing various diseases including cancers. Bcl-2 has drawn a considerable attention as a potential target for developing a pro-apoptotic agent for cancers. We here present the development of a specific protein binder against human Bcl-2 and its cytosolic delivery to effectively induce apoptosis of cancer cells. The protein binder composed of leucine-rich repeat modules was selected for human Bcl-2, and its binding affinity was increased up to 60 nM through a modular evolution-based approach. The protein binder was efficiently delivered into cancer cells by an intracellular delivery system using a translocation domain from a bacterial exotoxin, resulting in a strong suppression of anti-apoptotic signaling in cancer cells. Our results demonstrate that the human Bcl-2-specific protein binder can act as a potent therapeutic agent for cancers.
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Affiliation(s)
- Yoo-Kyoung Sohn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Hak-Sung Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea.
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13
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Schmit NE, Neopane K, Hantschel O. Targeted Protein Degradation through Cytosolic Delivery of Monobody Binders Using Bacterial Toxins. ACS Chem Biol 2019; 14:916-924. [PMID: 31025848 PMCID: PMC7316569 DOI: 10.1021/acschembio.9b00113] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
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Monobodies
are small engineered binding proteins that, upon expression
in cells, can inhibit signaling of cytosolic oncoproteins with outstanding
selectivity. Efficacy may be further increased by inducing degradation
of monobody targets through fusion to the von Hippel–Lindau
(VHL) substrate receptor of the Cullin2-E3 ubiquitin ligase complex.
However, potential therapeutic use is currently limited, because of
the inability of monobody proteins to cross cellular membranes. Here,
we use a chimeric bacterial toxin, composed of the Shiga-like toxin
B (Stx2B) subunit and the translocation domain of Pseudomonas
aeruginosa exotoxin A (ETA-II) for delivery of VHL–monobody
protein fusions to target endogenous tyrosine kinases in cancer cells.
Depending on the expression of the Stx2B receptor Gb3 on the cell
surface, we show that monobodies are taken up by an endocytic route,
but are not degraded in lysosomes. Delivery of monobodies fused to
a nuclear localization signal resulted in accumulation in the nucleus,
thereby indirectly, but unequivocally, demonstrating cytosolic delivery.
Delivery of VHL fused to monobodies targeting the Lck tyrosine kinase
in T-cells resulted in reduced Lck protein levels, which was dependent
on the expression of Gb3. This led to the inhibition of proximal signaling
events downstream of the T-cell receptor complex. This work provides
a prime example of the delivery of a stoichiometric protein inhibitor
of an endogenous target protein to cells and inducing its degradation
without the need of genetic manipulation of target cells. It lays
the foundation for further in vivo exploitation of
this delivery system.
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Affiliation(s)
- Nadine Eliane Schmit
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Katyayanee Neopane
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Oliver Hantschel
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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14
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Lichtenstein BR, Höcker B. Engineering an AB 5 Protein Carrier. Sci Rep 2018; 8:12643. [PMID: 30139944 PMCID: PMC6107655 DOI: 10.1038/s41598-018-30910-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 08/07/2018] [Indexed: 11/18/2022] Open
Abstract
The promise of biologic therapeutics is hindered by the challenge to deliver their activity to biochemically relevant sites within diseased cells. The favourable application of the natural protein carriers of the AB5 toxin family to this challenge has been restricted owing to still unresolved requirements for assembling non-native cargo into carrier complexes. Here, we clarify the properties of fusion peptides which allow co-assembly of a selected fluorescent protein cargo with the non-toxic B subunit of a heat-labile enterotoxin. We establish the influence of sequence length, sequence identity and secondary structure of these linking domains on the assembly and disassembly of the complexes. Through our engineering framework we identify several non-native, reduced length fusion sequences that robustly assemble with the native carriers, maintain their ability to deliver protein cargo to cells, and demonstrate substantially refined in vitro properties. Constructs based upon these sequences should prove directly applicable to a variety of protein delivery challenges, and the described design framework should find immediate application to other members of the AB5 protein carrier family.
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Affiliation(s)
- Bruce R Lichtenstein
- Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany. .,Department of Biochemistry, University of Bayreuth, 95447, Bayreuth, Germany.
| | - Birte Höcker
- Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany. .,Department of Biochemistry, University of Bayreuth, 95447, Bayreuth, Germany.
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15
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Stewart MP, Langer R, Jensen KF. Intracellular Delivery by Membrane Disruption: Mechanisms, Strategies, and Concepts. Chem Rev 2018; 118:7409-7531. [PMID: 30052023 PMCID: PMC6763210 DOI: 10.1021/acs.chemrev.7b00678] [Citation(s) in RCA: 382] [Impact Index Per Article: 63.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intracellular delivery is a key step in biological research and has enabled decades of biomedical discoveries. It is also becoming increasingly important in industrial and medical applications ranging from biomanufacture to cell-based therapies. Here, we review techniques for membrane disruption-based intracellular delivery from 1911 until the present. These methods achieve rapid, direct, and universal delivery of almost any cargo molecule or material that can be dispersed in solution. We start by covering the motivations for intracellular delivery and the challenges associated with the different cargo types-small molecules, proteins/peptides, nucleic acids, synthetic nanomaterials, and large cargo. The review then presents a broad comparison of delivery strategies followed by an analysis of membrane disruption mechanisms and the biology of the cell response. We cover mechanical, electrical, thermal, optical, and chemical strategies of membrane disruption with a particular emphasis on their applications and challenges to implementation. Throughout, we highlight specific mechanisms of membrane disruption and suggest areas in need of further experimentation. We hope the concepts discussed in our review inspire scientists and engineers with further ideas to improve intracellular delivery.
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Affiliation(s)
- Martin P. Stewart
- Department of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, USA
- The Koch Institute for Integrative Cancer Research,
Massachusetts Institute of Technology, Cambridge, USA
| | - Robert Langer
- Department of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, USA
- The Koch Institute for Integrative Cancer Research,
Massachusetts Institute of Technology, Cambridge, USA
| | - Klavs F. Jensen
- Department of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, USA
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16
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Luginbuehl V, Meier N, Kovar K, Rohrer J. Intracellular drug delivery: Potential usefulness of engineered Shiga toxin subunit B for targeted cancer therapy. Biotechnol Adv 2018; 36:613-623. [PMID: 29432805 DOI: 10.1016/j.biotechadv.2018.02.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 01/30/2018] [Accepted: 02/05/2018] [Indexed: 12/15/2022]
Abstract
A treasure trove of intracellular cancer drug targets remains hidden behind cell membranes. However, engineered pathogen-derived toxins such as Shiga toxins can deliver small or macromolecular drugs to specific intracellular organelles. After binding to ganglioglobotriaosylceramide (Gb3, CD77), the non-toxic subunit B (StxB) of the Shiga-holotoxin is endocytosed and delivers its payload by a unique retrograde trafficking pathway via the endoplasmic reticulum to the cytosol. This review provides an overview of biomedical applications of StxB-based drug delivery systems in targeted cancer diagnosis and therapy. Biotechnological production of the Stx-material is discussed from the perspective of developing efficacious and safe therapeutics.
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Affiliation(s)
- Vera Luginbuehl
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Nicolas Meier
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Karin Kovar
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Jack Rohrer
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland.
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17
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Ryou JH, Sohn YK, Kim DG, Kyeong HH, Kim HS. Engineering and cytosolic delivery of a native regulatory protein and its variants for modulation of ERK2 signaling pathway. Biotechnol Bioeng 2018; 115:839-849. [PMID: 29240226 DOI: 10.1002/bit.26516] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 10/30/2017] [Accepted: 12/04/2017] [Indexed: 12/24/2022]
Abstract
The modulation of a cell signaling process using a molecular binder followed by an analysis of the cellular response is crucial for understanding its role in the cellular function and developing pharmaceuticals. Herein, we present the modulation of the ERK2-mediated signaling pathway through the cytosolic delivery of a native regulatory protein for ERK2, that is, PEA-15 (phosphoprotein enriched in astrocytes, 15 kDa), and its engineered variants using a bacterial toxin-based delivery system. Based on biochemical and structural analyses, PEA-15 variants with different phosphorylation sites and a high affinity for ERK2 were designed. Semi-rational approach led to about an 830-fold increase in the binding affinity of PEA-15, resulting in more effective modulation of the ERK2-mediated signaling. Our approach enabled an understanding of the cellular function of the ERK2-mediated signaling process and the effect of PEA-15 phosphorylation on its action as an ERK2 blocker. We demonstrated the utility and potential of our approach by showing an efficient cytosolic delivery of these PEA-15 variants and the effective suppression of cell proliferation through the inhibition of the ERK2 function. The present approach can be used broadly for modulating the cell signaling processes and understanding their roles in cellular function, as well as for the development of therapeutics.
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Affiliation(s)
- Jeong-Hyun Ryou
- Graduate School of Medical Science & Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Yoo-Kyoung Sohn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Dong-Gun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Hyun-Ho Kyeong
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Hak-Sung Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
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18
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Abstract
Over the past two decades, hundreds of new somatic mutations have been identified in tumours, and a few dozen novel cancer therapeutics that selectively target these mutated oncoproteins have entered clinical practice. This development has resulted in clinical breakthroughs for a few tumour types, but more commonly patients' overall survival has not improved because of the development of drug resistance. Furthermore, only a very limited number of oncoproteins, largely protein kinases, are successfully targeted, whereas most non-kinase oncoproteins inside cancer cells remain untargeted. Engineered small protein inhibitors offer great promise in targeting a larger variety of oncoproteins with better efficacy and higher selectivity. In this article, I focus on a promising class of synthetic binding proteins, termed monobodies, that we have shown to inhibit previously untargetable protein-protein interactions in different oncoproteins. I will discuss the great promise alongside the technical challenges inherent in converting monobodies from potent pre-clinical target validation tools to next-generation protein-based therapeutics.
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Affiliation(s)
- Oliver Hantschel
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
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19
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Kim HY, Kang JA, Ryou JH, Lee GH, Choi DS, Lee DE, Kim HS. Intracellular Protein Delivery System Using a Target-Specific Repebody and Translocation Domain of Bacterial Exotoxin. ACS Chem Biol 2017; 12:2891-2897. [PMID: 29019389 DOI: 10.1021/acschembio.7b00562] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
With the high efficacy of protein-based therapeutics and plenty of intracellular drug targets, cytosolic protein delivery in a cell-specific manner has attracted considerable attention in the field of precision medicine. Herein, we present an intracellular protein delivery system based on a target-specific repebody and the translocation domain of Pseudomonas aeruginosa exotoxin A. The delivery platform was constructed by genetically fusing an EGFR-specific repebody as a targeting moiety to the translocation domain, while a protein cargo was fused to the C-terminal end of the delivery platform. The delivery platform was revealed to efficiently translocate a protein cargo to the cytosol in a target-specific manner. We demonstrate the utility and potential of the delivery platform by showing a remarkable tumor regression with negligible toxicity in a xenograft mice model when gelonin was used as the cytotoxic protein cargo. The present platform can find wide applications to the cell-selective cytosolic delivery of diverse proteins in many areas.
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Affiliation(s)
- Hee-Yeon Kim
- Graduate School of Nanoscience and Technology (WCU), Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Jung Ae Kang
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute , 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do 580-185, Korea
| | - Jeong-Hyun Ryou
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Gyeong Hee Lee
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute , 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do 580-185, Korea
| | - Dae Seong Choi
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute , 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do 580-185, Korea
| | - Dong Eun Lee
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute , 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do 580-185, Korea
| | - Hak-Sung Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
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