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Hao L, Zhao RT, Welch NL, Tan EKW, Zhong Q, Harzallah NS, Ngambenjawong C, Ko H, Fleming HE, Sabeti PC, Bhatia SN. CRISPR-Cas-amplified urinary biomarkers for multiplexed and portable cancer diagnostics. Nat Nanotechnol 2023; 18:798-807. [PMID: 37095220 PMCID: PMC10359190 DOI: 10.1038/s41565-023-01372-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 03/10/2023] [Indexed: 05/03/2023]
Abstract
Synthetic biomarkers, bioengineered sensors that generate molecular reporters in diseased microenvironments, represent an emerging paradigm in precision diagnostics. Despite the utility of DNA barcodes as a multiplexing tool, their susceptibility to nucleases in vivo has limited their utility. Here we exploit chemically stabilized nucleic acids to multiplex synthetic biomarkers and produce diagnostic signals in biofluids that can be 'read out' via CRISPR nucleases. The strategy relies on microenvironmental endopeptidase to trigger the release of nucleic acid barcodes and polymerase-amplification-free, CRISPR-Cas-mediated barcode detection in unprocessed urine. Our data suggest that DNA-encoded nanosensors can non-invasively detect and differentiate disease states in transplanted and autochthonous murine cancer models. We also demonstrate that CRISPR-Cas amplification can be harnessed to convert the readout to a point-of-care paper diagnostic tool. Finally, we employ a microfluidic platform for densely multiplexed, CRISPR-mediated DNA barcode readout that can potentially evaluate complex human diseases rapidly and guide therapeutic decisions.
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Affiliation(s)
- Liangliang Hao
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Renee T Zhao
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Nicole L Welch
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA
- Harvard Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA, USA
| | - Edward Kah Wei Tan
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Qian Zhong
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Nour Saida Harzallah
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Chayanon Ngambenjawong
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Henry Ko
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Heather E Fleming
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Pardis C Sabeti
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Sangeeta N Bhatia
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
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2
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Abstract
Antimicrobial peptides (AMPs) constitute a promising class of alternatives to antibiotics to curb antimicrobial resistance. Nonetheless, their utility as a systemic agent is hampered by short circulation time and toxicity. Infection sites, analogous to tumors, harbor an aberrant microenvironment that has the potential to be exploited to develop conditionally activated therapeutics with an improved therapeutic index. In particular, we identified strategies to prolong systemic circulation of small, cationic AMPs in a mouse model of bacterial pneumonia. Specifically, we report an albumin-binding domain (ABD)-AMP conjugate as a long-circulating conditional AMP therapeutic with a masked activity that can be liberated by proteases in the infected tissue microenvironment. Our systemically administered conjugate enhanced the pulmonary delivery of active AMP while also reducing AMP exposure to other off-target organs. Importantly, this reduction in off-target exposure improved the safety profile of the AMP. The framework we present can be generalized to quantify and optimize the performance of this emerging class of conditional therapeutics.
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Affiliation(s)
- Chayanon Ngambenjawong
- Koch
Institute for Integrative Cancer Research, Institute for Medical Engineering
and Science, and Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Leslie W. Chan
- Koch
Institute for Integrative Cancer Research, Institute for Medical Engineering
and Science, and Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather E. Fleming
- Koch
Institute for Integrative Cancer Research, Institute for Medical Engineering
and Science, and Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Howard
Hughes Medical Institute, Cambridge, Massachusetts 02139, United States
| | - Sangeeta N. Bhatia
- Koch
Institute for Integrative Cancer Research, Institute for Medical Engineering
and Science, and Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Howard
Hughes Medical Institute, Cambridge, Massachusetts 02139, United States
- Department
of Medicine, Brigham and Women’s
Hospital and Harvard Medical School, Boston Massachusetts 02115, United States
- Broad Institute
of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02139, United States
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3
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Chan LW, Hern KE, Ngambenjawong C, Lee K, Kwon EJ, Hung DT, Bhatia SN. Selective Permeabilization of Gram-Negative Bacterial Membranes Using Multivalent Peptide Constructs for Antibiotic Sensitization. ACS Infect Dis 2021; 7:721-732. [PMID: 33689277 PMCID: PMC8043124 DOI: 10.1021/acsinfecdis.0c00805] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The drug-impermeable bacterial membrane in Gram-negative pathogens limits antibiotic access to intracellular drug targets. To expand our rapidly waning antibiotic arsenal, one approach is to improve the intracellular delivery of drugs with historically poor accumulation in Gram-negative bacteria. To do so, we engineered macromolecular potentiators to permeabilize the Gram-negative membrane to facilitate drug influx. Potentiators, known as WD40, were synthesized by grafting multiple copies of a cationic α-helical antimicrobial peptide, WLBU2, onto a dextran polymer scaffold. WD40 enabled drug uptake in the model pathogen P. aeruginosa, a capability that was not observed with unmodified WLBU2 peptide. WD40 was able to reduce minimum inhibitory concentrations of a drug panel by up to 3 orders of magnitude. Hydrophobic and highly three-dimensional antibiotics exhibited the greatest potentiation. Antibiotic activity was potentiated in several clinical strains and resulted in sensitization of drug-resistant strains to rifampin, a drug not previously used for Gram-negative infections.
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Affiliation(s)
- Leslie W. Chan
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Kelsey E. Hern
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Chayanon Ngambenjawong
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Katie Lee
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02139, United States
| | - Ester J. Kwon
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Deborah T. Hung
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02139, United States
- Department of Molecular Biology, Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts 02114, United States
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Sangeeta N. Bhatia
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02139, United States
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
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Liu GW, Prossnitz AN, Eng DG, Cheng Y, Subrahmanyam N, Pippin JW, Lamm RJ, Ngambenjawong C, Ghandehari H, Shankland SJ, Pun SH. Glomerular disease augments kidney accumulation of synthetic anionic polymers. Biomaterials 2018; 178:317-325. [DOI: 10.1016/j.biomaterials.2018.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 05/31/2018] [Accepted: 06/02/2018] [Indexed: 12/22/2022]
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Ngambenjawong C, Sylvestre M, Gustafson HH, Pineda JMB, Pun SH. Reversibly Switchable, pH-Dependent Peptide Ligand Binding via 3,5-Diiodotyrosine Substitutions. ACS Chem Biol 2018; 13:995-1002. [PMID: 29481044 DOI: 10.1021/acschembio.8b00171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cell type-specific targeting ligands utilized in drug delivery applications typically recognize receptors that are overexpressed on the cells of interest. Nonetheless, these receptors may also be expressed, to varying extents, on off-target cells, contributing to unintended side effects. For the selectivity profile of targeting ligands in cancer therapy to be improved, stimuli-responsive masking of these ligands with acid-, redox-, or enzyme-cleavable molecules has been reported, whereby the targeting ligands are exposed in specific environments, e.g., acidic tumor hypoxia. One possible drawback of these systems lies in their one-time, permanent trigger, which enables the "demasked" ligands to bind off-target cells if released back into the systemic circulation. A promising strategy to address the aforementioned problem is to design ligands that show selective binding based on ionization state, which may be microenvironment-dependent. In this study, we report a systematic strategy to engineer low pH-selective targeting peptides using an M2 macrophage-targeting peptide (M2pep) as an example. 3,5-Diiodotyrosine mutagenesis into native tyrosine residues of M2pep confers pH-dependent binding behavior specific to acidic environment (pH 6) when the amino acid is protonated into the native tyrosine-like state. At physiological pH of 7.4, the hydroxyl group of 3,5-diiodotyrosine on the peptide is deprotonated leading to interruption of the peptide native binding property. Our engineered pH-responsive M2pep (Ac-Y-Î-Î) binds target M2 macrophages more selectively at pH 6 than at pH 7.4. In addition, 3,5-diiodotyrosine substitutions also improve serum stability of the peptide. Finally, we demonstrate pH-dependent reversibility in target binding via a postbinding peptide elution study. The strategy presented here should be applicable for engineering pH-dependent functionality of other targeting peptides with potential applications in physiology-dependent in vivo targeting applications (e.g., targeting hypoxic tumor/inflammation) or in in vitro receptor identification.
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Affiliation(s)
- Chayanon Ngambenjawong
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, Washington 98195, United States
| | - Meilyn Sylvestre
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, Washington 98195, United States
| | - Heather H. Gustafson
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, Washington 98195, United States
| | - Julio Marco B. Pineda
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, Washington 98195, United States
| | - Suzie H. Pun
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, Washington 98195, United States
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Ngambenjawong C, Gustafson HH, Sylvestre M, Pun SH. A Facile Cyclization Method Improves Peptide Serum Stability and Confers Intrinsic Fluorescence. Chembiochem 2017; 18:2395-2398. [PMID: 29044914 DOI: 10.1002/cbic.201700446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Indexed: 01/03/2023]
Abstract
Peptides are a growing class of macromolecules used in pharmaceutics. The path toward the clinical use of candidate peptides involves sequence optimization and cyclization for stability and affinity. For internalized peptides, tagging is also often required for intracellular trafficking studies, although fluorophore conjugation has an impact on peptide binding, permeability, and localization. Herein, a strategy based on cysteine arylation with tetrafluoroterephthalonitrile (4F-2CN), which simultaneously cyclizes peptides and imparts fluorescence, is reported. The 4F-2CN cyclization of an M2 macrophage-targeting peptide yields, in a single step, a peptide with improved serum stability, intrinsic fluorescence, and increased binding affinity. In a murine breast cancer model, it is demonstrated that the intrinsic fluorescence from the cyclized peptide is sufficient for monitoring biodistribution by whole-organ fluorescence imaging and cell internalization by flow cytometry.
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Affiliation(s)
- Chayanon Ngambenjawong
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, 3720 15th Ave NE, Foege, Seattle, WA, 98195, USA
| | - Heather H Gustafson
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, 3720 15th Ave NE, Foege, Seattle, WA, 98195, USA
| | - Meilyn Sylvestre
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, 3720 15th Ave NE, Foege, Seattle, WA, 98195, USA
| | - Suzie H Pun
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, 3720 15th Ave NE, Foege, Seattle, WA, 98195, USA
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Ngambenjawong C, Pun SH. Multivalent polymers displaying M2 macrophage-targeting peptides improve target binding avidity and serum stability. ACS Biomater Sci Eng 2017; 3:2050-2053. [PMID: 29430522 DOI: 10.1021/acsbiomaterials.7b00332] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tumor-associated macrophages (TAMs) display a spectrum of phenotypes ranging from pro-tumoral/anti-inflammatory "M2-like" to anti-tumoral/pro-inflammatory "M1-like" subtypes and, consequently, high intratumoral M2-to-M1 ratios are typically indicative of poor disease prognosis. Cancer immunotherapies that selectively modulate M2-like TAMs, enabling reversal of the M2-to-M1 ratio, represent a promising anti-cancer intervention but are difficult to implement due to the lack of effective targeting systems. In this study, we report the development of high avidity, M2 macrophage-selective targeted drug delivery platforms based on M2 macrophage-targeting peptides (M2pep) grafted onto poly(N-(2-hydroxypropyl) methacrylamide). Furthermore, these M2pep-grafted polymers also exhibit improved serum stability along with M2 macrophage-selective toxicity.
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Affiliation(s)
- Chayanon Ngambenjawong
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, United States
| | - Suzie H Pun
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, United States
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8
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Ngambenjawong C, Gustafson HH, Pun SH. Progress in tumor-associated macrophage (TAM)-targeted therapeutics. Adv Drug Deliv Rev 2017; 114:206-221. [PMID: 28449873 DOI: 10.1016/j.addr.2017.04.010] [Citation(s) in RCA: 456] [Impact Index Per Article: 65.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 04/13/2017] [Accepted: 04/14/2017] [Indexed: 02/06/2023]
Abstract
As an essential innate immune population for maintaining body homeostasis and warding off foreign pathogens, macrophages display high plasticity and perform diverse supportive functions specialized to different tissue compartments. Consequently, aberrance in macrophage functions contributes substantially to progression of several diseases including cancer, fibrosis, and diabetes. In the context of cancer, tumor-associated macrophages (TAMs) in tumor microenvironment (TME) typically promote cancer cell proliferation, immunosuppression, and angiogenesis in support of tumor growth and metastasis. Oftentimes, the abundance of TAMs in tumor is correlated with poor disease prognosis. Hence, significant attention has been drawn towards development of cancer immunotherapies targeting these TAMs; either depleting them from tumor, blocking their pro-tumoral functions, or restoring their immunostimulatory/tumoricidal properties. This review aims to introduce readers to various aspects in development and evaluation of TAM-targeted therapeutics in pre-clinical and clinical stages.
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Affiliation(s)
- Chayanon Ngambenjawong
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, United States
| | - Heather H Gustafson
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, United States
| | - Suzie H Pun
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, United States.
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9
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Abstract
Peptide cyclization is a strategy used to improve stability and activity of peptides. The most commonly used cyclization method is disulfide bridge formation of cysteine-containing peptides, as is typically found in nature. Over the years, an increasing number of alternative chemistries for peptide cyclization with improved efficiency, kinetics, orthogonality, and stability have been reported. However, there has been less appreciation for the opportunity to fine-tune peptide activity via the diverse chemical entities introduced at the site of linkage by different cyclization strategies. Here, we demonstrate how cyclization optimization of an M2 "anti-inflammatory" macrophage-binding peptide (M2pep) resulted in a significant increase in binding affinity of the optimized analog to M2 macrophages while maintaining binding selectivity compared to M1 "pro-inflammatory" macrophages. In this study, we report synthesis and evaluation of four cyclic M2pep(RY) analogs with diverse cyclization strategies: (1) Asp-[amide]-Lys, (2) azido-Lys-[triazole(copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC))]-propargyl-Gly, (3) Cys-[decafluorobiphenyl (DFBP)]-Cys, and (4) Cys-[decafluorobiphenyl sulfone (DFS)]-Cys, whereby the chemical entity or linker at the linkage site is shown in the square bracket and is between the residues involved in cyclization. These peptides are compared to a disulfide-cyclized M2pep(RY) that we previously reported as a serum-stable, affinity-enhanced analog to the original linear M2pep. DFBP-cyclized M2pep(RY) exhibits the highest binding activity to M2 macrophages with apparent dissociation constant (KD) about 2.03 μM compared to 36.3 μM for the original disulfide-cyclized M2pep(RY) and 220 μM for the original linear peptide. DFS-cyclized M2pep(RY) also binds more strongly than the original cyclized analog, whereas amide- and triazole-cyclized M2pep(RY) analogs bind less strongly. We verified that DFBP alone has negligible binding to M2 macrophages and the incorporation of diphenylalanine to the original sequence improves binding activity at the expense of solubility and increased toxicity. In conclusion, we report development of cyclic M2pep(RY) analogs with diverse cyclization strategies leading to the discovery of DFBP-cyclized M2pep(RY) with enhanced M2 macrophage-binding activity.
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Affiliation(s)
- Chayanon Ngambenjawong
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington , Seattle, Washington 98195, United States
| | - Julio Marco B Pineda
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington , Seattle, Washington 98195, United States
| | - Suzie H Pun
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington , Seattle, Washington 98195, United States
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10
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Ngambenjawong C, Gustafson HH, Pineda JM, Kacherovsky NA, Cieslewicz M, Pun SH. Serum Stability and Affinity Optimization of an M2 Macrophage-Targeting Peptide (M2pep). Am J Cancer Res 2016; 6:1403-14. [PMID: 27375788 PMCID: PMC4924508 DOI: 10.7150/thno.15394] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 04/14/2016] [Indexed: 11/05/2022] Open
Abstract
Tumor associated macrophages (TAMs) are a major stromal component of the tumor microenvironment in several cancers. TAMs are a potential target for adjuvant cancer therapies due to their established roles in promoting proliferation of cancer cells, angiogenesis, and metastasis. We previously discovered an M2 macrophage-targeting peptide (M2pep) which was successfully used to target and deliver a pro-apoptotic KLA peptide to M2-like TAMs in a CT-26 colon carcinoma model. However, the effectiveness of in vivo TAM-targeting using M2pep is limited by its poor serum stability and low binding affinity. In this study, we synthesized M2pep derivatives with the goals of increasing serum stability and binding affinity. Serum stability evaluation of M2pepBiotin confirmed its rapid degradation attributed to exolytic cleavage from the N-terminus and endolytic cleavages at the W10/W11 and S16/K17 sites. N-terminal acetylation of M2pepBiotin protected the peptide against the exolytic degradation while W10w and K(17,18,19)k substitutions were able to effectively protect endolytic degradation at their respective cleavage sites. However, no tested amino acid changes at the W10 position resulted in both protease resistance at that site and retention of binding activity. Therefore, cyclization of M2pep was investigated. Cyclized M2pep better resisted serum degradation without compromising binding activity to M2 macrophages. During the serum stability optimization process, we also discovered that K9R and W10Y substitutions significantly enhanced binding affinity of M2pep. In an in vitro binding study of different M2pep analogs pre-incubated in mouse serum, cyclic M2pep with K9R and W10Y modifications (cyclic M2pep(RY)) retained the highest binding activity to M2 macrophages over time due to its improved serum stability. Finally, we evaluated the in vivo accumulation of sulfo-Cy5-labeled M2pep and cyclic M2pep(RY) in both the CT-26 and 4T1 breast carcinoma models. Cyclic M2pep(RY) outperformed M2pep in both tumor localization and selective accumulation in M2-like TAMs. In conclusion, we report cyclic M2pep(RY) as our lead M2pep analog with improved serum stability and M2 macrophage-binding activity. Its enhanced utility as an in vivo M2-like-TAM-targeting agent was demonstrated in two tumor models, and is expected to be applicable for other tumor models or in models of M2 macrophage-related diseases.
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Chu DSH, Bocek MJ, Shi J, Ta A, Ngambenjawong C, Rostomily RC, Pun SH. Multivalent display of pendant pro-apoptotic peptides increases cytotoxic activity. J Control Release 2015; 205:155-61. [PMID: 25596326 DOI: 10.1016/j.jconrel.2015.01.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 01/11/2015] [Accepted: 01/13/2015] [Indexed: 10/24/2022]
Abstract
Several cationic antimicrobial peptides have been investigated as potential anti-cancer drugs due to their demonstrated selective toxicity towards cancer cells relative to normal cells. For example, intracellular delivery of KLA, a pro-apoptotic peptide, results in toxicity against a variety of cancer cell lines; however, the relatively low activity and small size lead to rapid renal excretion when applied in vivo, limiting its therapeutic potential. In this work, apoptotic peptide-polymer hybrid materials were developed to increase apoptotic peptide activity via multivalent display. Multivalent peptide materials were prepared with comb-like structure by RAFT copolymerization of peptide macromonomers with N-(2-hydroxypropyl) methacrylamide (HPMA). Polymers displayed a GKRK peptide sequence for targeting p32, a protein often overexpressed on the surface of cancer cells, either fused with or as a comonomer to a KLA macromonomer. In three tested cancer cell lines, apoptotic polymers were significantly more cytotoxic than free peptides as evidenced by an order of magnitude decrease in IC50 values for the polymers compared to free peptide. The uptake efficiency and intracellular trafficking of one polymer construct was determined by radiolabeling and subcellular fractionation. Despite their more potent cytotoxic profile, polymeric KLA constructs have poor cellular uptake efficiency (<1%). A significant fraction (20%) of internalized constructs localize with intact mitochondrial fractions. In an effort to increase cellular uptake, polymer amines were converted to guanidines by reaction with O-methylisourea. Guanidinylated polymers disrupted function of isolated mitochondria more than their lysine-based analogs, but overall toxicity was decreased, likely due to inefficient mitochondrial trafficking. Thus, while multivalent KLA polymers are more potent than KLA peptides, these materials can be substantially improved by designing next generation materials with improved cellular internalization and mitochondrial targeting efficiency.
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Affiliation(s)
- David S H Chu
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, USA
| | - Michael J Bocek
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, USA
| | - Julie Shi
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, USA
| | - Anh Ta
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, USA
| | - Chayanon Ngambenjawong
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, USA
| | - Robert C Rostomily
- Department of Neurological Surgery, University of Washington, Seattle, WA 98195, USA
| | - Suzie H Pun
- Department of Bioengineering and Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, USA.
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