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Rood MTM, Raspe M, ten Hove JB, Jalink K, Velders AH, van Leeuwen FWB. MMP-2/9-Specific Activatable Lifetime Imaging Agent. SENSORS (BASEL, SWITZERLAND) 2015; 15:11076-91. [PMID: 25985157 PMCID: PMC4481940 DOI: 10.3390/s150511076] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 05/01/2015] [Accepted: 05/06/2015] [Indexed: 12/13/2022]
Abstract
Optical (molecular) imaging can benefit from a combination of the high signal-to-background ratio of activatable fluorescence imaging with the high specificity of luminescence lifetime imaging. To allow for this combination, both imaging techniques were integrated in a single imaging agent, a so-called activatable lifetime imaging agent. Important in the design of this imaging agent is the use of two luminophores that are tethered by a specific peptide with a hairpin-motive that ensured close proximity of the two while also having a specific amino acid sequence available for enzymatic cleavage by tumor-related MMP-2/9. Ir(ppy)3 and Cy5 were used because in close proximity the emission intensities of both luminophores were quenched and the influence of Cy5 shortens the Ir(ppy)3 luminescence lifetime from 98 ns to 30 ns. Upon cleavage in vitro, both effects are undone, yielding an increase in Ir(ppy)3 and Cy5 luminescence and a restoration of Ir(ppy)3 luminescence lifetime to 94 ns. As a reference for the luminescence activation, a similar imaging agent with the more common Cy3-Cy5 fluorophore pair was used. Our findings underline that the combination of enzymatic signal activation with lifetime imaging is possible and that it provides a promising method in the design of future disease specific imaging agents.
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Affiliation(s)
- Marcus T M Rood
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden 2300RC, The Netherlands.
| | - Marcel Raspe
- Division of Cell Biology I, Netherlands Cancer Institute, Amsterdam 1066CX, The Netherlands.
| | - Jan Bart ten Hove
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden 2300RC, The Netherlands.
- Laboratory of BioNanoTechnology, Wageningen University, Wageningen 6700EK, The Netherlands.
| | - Kees Jalink
- Division of Cell Biology I, Netherlands Cancer Institute, Amsterdam 1066CX, The Netherlands.
| | - Aldrik H Velders
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden 2300RC, The Netherlands.
- Laboratory of BioNanoTechnology, Wageningen University, Wageningen 6700EK, The Netherlands.
| | - Fijs W B van Leeuwen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden 2300RC, The Netherlands.
- Laboratory of BioNanoTechnology, Wageningen University, Wageningen 6700EK, The Netherlands.
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102
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Okusanya OT, DeJesus EM, Jiang JX, Judy RP, Venegas OG, Deshpande CG, Heitjan DF, Nie S, Low PS, Singhal S. Intraoperative molecular imaging can identify lung adenocarcinomas during pulmonary resection. J Thorac Cardiovasc Surg 2015; 150:28-35.e1. [PMID: 26126457 DOI: 10.1016/j.jtcvs.2015.05.014] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 04/15/2015] [Accepted: 05/02/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND More than 80,000 people undergo resection of a pulmonary tumor each year, and the only method to determine if the tumor is malignant is histologic analysis. We propose that a targeted molecular contrast agent could bind lung adenocarcinomas, which could be identified using real-time optical imaging at the time of surgery. METHODS Fifty patients with a biopsy-proven lung adenocarcinoma were enrolled. Before surgery, patients were systemically administered 0.1 mg/kg of a fluorescent folate receptor alpha (FRα)-targeted molecular contrast agent by intravenous infusion. During surgery, tumors were imaged in situ and ex vivo, after the lung parenchyma was dissected to directly expose the tumor to the imaging system. RESULTS Tumors ranged from 0.3 to 7.5 cm (mean: 2.6 cm), and 46 of 50 (92%) lung adenocarcinomas were fluorescent. No false uptake occurred, and in 2 cases, intraoperative imaging revealed tumor metastases (3 mm and 6 mm) that were not recognized preoperatively. Four adenocarcinomas were not fluorescent, and immunohistochemistry showed that these adenocarcinomas did not express FRα. Tumor fluorescence was independent of nodule size, uptake of 2-deoxy-2-((18)F)fluoro-D-glucose, histology, and tumor differentiation. Molecular imaging could identify only 7 of the 50 adenocarcinomas in situ in the patient without bisection. The most important predictor of the success of molecular imaging in locating the tumor in situ was the distance of the nodule from the pleural surface. CONCLUSIONS Intraoperative molecular imaging with a targeted contrast agent can identify lung adenocarcinomas, and this technology is currently useful in patients with subpleural tumors, irrespective of size. With further refinements, this tool may prove useful in locating adenocarcinomas that are deeper in the lung parenchyma, in lymph nodes, and at pleural and resection margins.
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Affiliation(s)
- Olugbenga T Okusanya
- Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pa
| | - Elizabeth M DeJesus
- Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pa
| | - Jack X Jiang
- Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pa
| | - Ryan P Judy
- Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pa
| | - Ollin G Venegas
- Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pa
| | - Charuhas G Deshpande
- Department of Pathology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pa
| | - Daniel F Heitjan
- Department of Biostatistics & Epidemiology, University of Pennsylvania, Philadelphia, Pa
| | - Shuming Nie
- Departments of Biomedical Engineering and Chemistry, Emory University, Atlanta, Ga
| | - Philip S Low
- Department of Chemistry, Purdue University, West Lafayette, Ind
| | - Sunil Singhal
- Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pa.
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104
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Raju SC, Hauff SJ, Lemieux AJ, Orosco RK, Gross AM, Nguyen LT, Savariar E, Moss W, Whitney M, Cohen EE, Lippman SM, Tsien RY, Ideker T, Advani SJ, Nguyen QT. Combined TP53 mutation/3p loss correlates with decreased radiosensitivity and increased matrix-metalloproteinase activity in head and neck carcinoma. Oral Oncol 2015; 51:470-5. [PMID: 25735654 PMCID: PMC4427339 DOI: 10.1016/j.oraloncology.2015.01.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 01/22/2015] [Accepted: 01/25/2015] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Patients with head and neck squamous cell carcinoma (HNSCC) containing TP53 mutation and 3p deletion ("double-hit") have poorer prognosis compared to patients with either event alone ("single-hit"). The etiology for worse clinical outcomes in patients with "double-hit" cancers is unclear. We compared radiosensitivity of cell lines containing both TP53 mutations and deletion of Fragile Histidine Triad (FHIT, the gene most commonly associated with 3p deletion) to "single-hit" lines with only TP53 mutation. We compared radiosensitivity in a "single-hit" cell line with TP53 mutation converted to "double-hit" using RNA interference targeting FHIT. Finally, we compared matrixmetalloproteinase-2/9 (MMP-2/9) activity, a previously-established biomarker for tumor aggressiveness, in xenograft tumors derived from these cell lines. MATERIALS/METHODS TP53 mutation and FHIT deletion profiles of HNSCC lines were established using Cancer Cell Line Encyclopedia (CCLE). We used RNA-interference to convert a "single-hit" cell line (SCC4) to "double-hit". Cultured cells were examined for radiosensitivity and cisplatin sensitivity. MMP-2/9 activity was evaluated in "double-hit" versus "single-hit" tumors using ratiometric activatable cell-penetrating peptide (RACPP) in tongue (n=17) and flank xenografts (n=4). RESULTS Radiotherapy caused greater double-stranded DNA breaks in "single-hit" vs naturally occurring and engineered "double-hit" cells. In-vivo, "double-hit" xenografts demonstrated higher MMP-2/9 activity compared to "single-hit" xenografts (p<0.01). There was no difference in cisplatin sensitivity between the cell lines. CONCLUSIONS TP53 mutation combined with FHIT deletion correlates with decreased radiosensitivity in HNC cell lines. Xenograft from "double-hit" cells exhibit increased MMP-2/9 activity. These findings may in part account for the worse clinical outcome seen in patients with HNSCC "double-hit" tumors.
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Affiliation(s)
- Sharat C Raju
- Division of Head and Neck Surgery, University of California, San Diego, CA, USA
| | - Samantha J Hauff
- Division of Head and Neck Surgery, University of California, San Diego, CA, USA
| | - Aaron J Lemieux
- Division of Head and Neck Surgery, University of California, San Diego, CA, USA
| | - Ryan K Orosco
- Division of Head and Neck Surgery, University of California, San Diego, CA, USA
| | - Andrew M Gross
- Bioinfomatics and Systems Biology, University of California, San Diego, CA, USA
| | - Linda T Nguyen
- Division of Head and Neck Surgery, University of California, San Diego, CA, USA
| | | | - William Moss
- Division of Head and Neck Surgery, University of California, San Diego, CA, USA
| | - Michael Whitney
- Department of Pharmacology, University of California, San Diego, CA, USA
| | | | | | - Roger Y Tsien
- Department of Pharmacology, University of California, San Diego, CA, USA; Howard Hughes Medical Institute, San Diego, CA, USA
| | - Trey Ideker
- Bioinfomatics and Systems Biology, University of California, San Diego, CA, USA; Division of Medical Genetics, University of California, San Diego, CA, USA
| | - Sunil J Advani
- Department of Radiation Medicine and Applied Sciences, University of California, San Diego, CA, USA
| | - Quyen T Nguyen
- Division of Head and Neck Surgery, University of California, San Diego, CA, USA; Department of Pharmacology, University of California, San Diego, CA, USA; Moores Cancer Center, San Diego, CA, USA.
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105
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Wong PT, Choi SK. Mechanisms of Drug Release in Nanotherapeutic Delivery Systems. Chem Rev 2015; 115:3388-432. [DOI: 10.1021/cr5004634] [Citation(s) in RCA: 349] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Pamela T. Wong
- Michigan
Nanotechnology Institute
for Medicine and Biological Sciences, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Seok Ki Choi
- Michigan
Nanotechnology Institute
for Medicine and Biological Sciences, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States
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106
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van Duijnhoven SMJ, Robillard MS, Langereis S, Grüll H. Bioresponsive probes for molecular imaging: concepts and in vivo applications. CONTRAST MEDIA & MOLECULAR IMAGING 2015; 10:282-308. [PMID: 25873263 DOI: 10.1002/cmmi.1636] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 01/24/2015] [Accepted: 02/03/2015] [Indexed: 12/30/2022]
Abstract
Molecular imaging is a powerful tool to visualize and characterize biological processes at the cellular and molecular level in vivo. In most molecular imaging approaches, probes are used to bind to disease-specific biomarkers highlighting disease target sites. In recent years, a new subset of molecular imaging probes, known as bioresponsive molecular probes, has been developed. These probes generally benefit from signal enhancement at the site of interaction with its target. There are mainly two classes of bioresponsive imaging probes. The first class consists of probes that show direct activation of the imaging label (from "off" to "on" state) and have been applied in optical imaging and magnetic resonance imaging (MRI). The other class consists of probes that show specific retention of the imaging label at the site of target interaction and these probes have found application in all different imaging modalities, including photoacoustic imaging and nuclear imaging. In this review, we present a comprehensive overview of bioresponsive imaging probes in order to discuss the various molecular imaging strategies. The focus of the present article is the rationale behind the design of bioresponsive molecular imaging probes and their potential in vivo application for the detection of endogenous molecular targets in pathologies such as cancer and cardiovascular disease.
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Affiliation(s)
- Sander M J van Duijnhoven
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.,Department of Minimally Invasive Healthcare, Philips Research, Eindhoven, The Netherlands
| | - Marc S Robillard
- Department of Minimally Invasive Healthcare, Philips Research, Eindhoven, The Netherlands
| | - Sander Langereis
- Department of Minimally Invasive Healthcare, Philips Research, Eindhoven, The Netherlands
| | - Holger Grüll
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.,Department of Minimally Invasive Healthcare, Philips Research, Eindhoven, The Netherlands
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107
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Rosenthal EL, Warram JM, Bland KI, Zinn KR. The status of contemporary image-guided modalities in oncologic surgery. Ann Surg 2015; 261:46-55. [PMID: 25599326 DOI: 10.1097/sla.0000000000000622] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE To review the current trends in optical imaging to guide oncologic surgery. BACKGROUND Surgical resection remains the cornerstone of therapy for patients with early stage solid malignancies and more than half of all patients with cancer undergo surgery each year. The technical ability of the surgeon to obtain clear surgical margins at the initial resection remains crucial to improve overall survival and long-term morbidity. Current resection techniques are largely based on subjective and subtle changes associated with tissue distortion by invasive cancer. As a result, positive surgical margins occur in a significant portion of tumor resections, which is directly correlated with a poor outcome. METHODS A comprehensive review of studies evaluating optical imaging techniques is performed. RESULTS A variety of cancer imaging techniques have been adapted or developed for intraoperative surgical guidance that have been shown to improve functional and oncologic outcomes in randomized clinical trials. There are also a large number of novel, cancer-specific contrast agents that are in early stage clinical trials and preclinical development that demonstrate significant promise to improve real-time detection of subclinical cancer in the operative setting. CONCLUSIONS There has been an explosion of intraoperative imaging techniques that will become more widespread in the next decade.
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Affiliation(s)
- Eben L Rosenthal
- *Departments of Surgery and †Radiology, The University of Alabama at Birmingham, Birmingham, AL
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108
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Zhou JZ, Riquelme MA, Gao X, Ellies LG, Sun LZ, Jiang JX. Differential impact of adenosine nucleotides released by osteocytes on breast cancer growth and bone metastasis. Oncogene 2015; 34:1831-42. [PMID: 24837364 PMCID: PMC4315766 DOI: 10.1038/onc.2014.113] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 03/19/2014] [Accepted: 04/03/2014] [Indexed: 12/23/2022]
Abstract
Extracellular ATP has been shown to either inhibit or promote cancer growth and migration; however, the mechanism underlying this discrepancy remained elusive. Here we demonstrate the divergent roles of ATP and adenosine released by bone osteocytes on breast cancers. We showed that conditioned media (CM) collected from osteocytes treated with alendronate (AD), a bisphosphonate drug, inhibited the migration of human breast cancer MDA-MB-231 cells. Removal of the extracellular ATP by apyrase in CM abolished this effect, suggesting the involvement of ATP. ATP exerted its inhibitory effect through the activation of purinergic P2X receptor signaling in breast cancer cells evidenced by the attenuation of the inhibition by an antagonist, oxidized ATP, as well as knocking down P2X7 with small interfering RNA (siRNA), and the inhibition of migration by an agonist, BzATP. Intriguingly, ATP had a biphasic effect on breast cancer cells-lower dosage inhibited but higher dosage promoted its migration. The stimulatory effect on migration was blocked by an adenosine receptor antagonist, MRS1754, ARL67156, an ecto-ATPase inhibitor, and A2A receptor siRNA, suggesting that in contrast to ATP, adenosine, a metabolic product of ATP, promoted migration of breast cancer cells. Consistently, non-hydrolyzable ATP, ATPγS, only inhibited but did not promote cancer cell migration. ATP also had a similar inhibitory effect on the Py8119 mouse mammary carcinoma cells; however, adenosine had no effect owing to the absence of the A2A receptor. Consistently, ATPγS inhibited, whereas adenosine promoted anchorage-independent growth of MDA-MB-231 cells. Our in vivo xenograft study showed a significant delay of tumor growth with the treatment of ATPγS. Moreover, the extent of bone metastasis in a mouse intratibial model was significantly reduced with the treatment of ATPγS. Together, our results suggest the distinct roles of ATP and adenosine released by osteocytes and the activation of corresponding receptors P2X7 and A2A signaling on breast cancer cell growth, migration and bone metastasis.
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Affiliation(s)
- Jade Z. Zhou
- Departments of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
| | - Manuel A. Riquelme
- Departments of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
| | - Xiaoli Gao
- Departments of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
| | - Lesley G. Ellies
- Department of Pathology, University of California, San Diego, La Jolla, CA 92093-0063, USA
| | - Lu-Zhe Sun
- Cellular and Structural Biology, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
- Cancer Therapy and Research Center, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
| | - Jean X. Jiang
- Departments of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
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109
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DSouza AV, Elliott JT, Gunn JR, Barth RJ, Samkoe KS, Tichauer KM, Pogue BW. Nodal lymph flow quantified with afferent vessel input function allows differentiation between normal and cancer-bearing nodes. BIOMEDICAL OPTICS EXPRESS 2015; 6:1304-17. [PMID: 25909014 PMCID: PMC4399669 DOI: 10.1364/boe.6.001304] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 03/11/2015] [Accepted: 03/12/2015] [Indexed: 05/27/2023]
Abstract
Morbidity and complexity involved in lymph node staging via surgical resection and biopsy could ideally be improved using node assay techniques that are non-invasive. While visible blue dyes are often used to locate the sentinel lymph nodes from draining lymphatic vessels near a tumor, they do not provide an in situ metric to evaluate presence of cancer. In this study, the transport kinetics of methylene blue were analyzed to determine the potential for better in situ information about metastatic involvement in the nodes. A rat model with cancer cells in the axillary lymph nodes was used, with methylene blue injection to image the fluorescence kinetics. The lymphatic flow from injection sites to nodes was imaged and the relative kinetics from feeding lymphatic ducts relative to lymph nodes was quantified. Large variability existed in raw fluorescence and transport patterns within each cohort resulting in no systematic difference between average nodal uptake in normal, sham control and cancer-bearing nodes. However, when the signal from the afferent lymph vessel fluorescence was used to normalize the signal of the lymph nodes, the high signal heterogeneity was reduced. Using a model, the lymph flow through the nodes [Formula: see text] was estimated to be 1.49 ± 0.64 ml/g/min in normal nodes, 1.53 ± 0.45 ml/g/min in sham control nodes, and reduced to 0.50 ± 0.24 ml/g/min in cancer-cell injected nodes. This summarizes the significant difference (p = 0.0002) between cancer-free and cancer-bearing nodes in normalized flow. This process of normalized flow imaging could be used as an in situ tool to detect metastatic involvement in nodes.
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Affiliation(s)
- Alisha V DSouza
- Thayer School of Engineering, Dartmouth College, Hanover NH 03755, USA ;
| | | | - Jason R Gunn
- Thayer School of Engineering, Dartmouth College, Hanover NH 03755, USA
| | - Richard J Barth
- Department of Medicine, Geisel School of Medicine, Hanover NH 03755, USA
| | - Kimberley S Samkoe
- Thayer School of Engineering, Dartmouth College, Hanover NH 03755, USA ; Department of Surgery, Geisel School of Medicine, Hanover NH 03755, USA
| | - Kenneth M Tichauer
- Biomedical Engineering, Illinois Institute of Technology, Chicago IL 60616, USA
| | - Brian W Pogue
- Thayer School of Engineering, Dartmouth College, Hanover NH 03755, USA ; Department of Surgery, Geisel School of Medicine, Hanover NH 03755, USA ;
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Buckel L, Savariar EN, Crisp JL, Jones KA, Hicks AM, Scanderbeg DJ, Nguyen QT, Sicklick JK, Lowy AM, Tsien RY, Advani SJ. Tumor radiosensitization by monomethyl auristatin E: mechanism of action and targeted delivery. Cancer Res 2015; 75:1376-1387. [PMID: 25681274 DOI: 10.1158/0008-5472.can-14-1931] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 02/04/2015] [Indexed: 12/19/2022]
Abstract
Intrinsic tumor resistance to radiotherapy limits the efficacy of ionizing radiation (IR). Sensitizing cancer cells specifically to IR would improve tumor control and decrease normal tissue toxicity. The development of tumor-targeting technologies allows for developing potent radiosensitizing drugs. We hypothesized that the anti-tubulin agent monomethyl auristatin E (MMAE), a component of a clinically approved antibody-directed conjugate, could function as a potent radiosensitizer and be selectively delivered to tumors using an activatable cell-penetrating peptide targeting matrix metalloproteinases and RGD-binding integrins (ACPP-cRGD-MMAE). We evaluated the ability of MMAE to radiosensitize both established cancer cells and a low-passage cultured human pancreatic tumor cell line using clonogenic and DNA damage assays. MMAE sensitized colorectal and pancreatic cancer cells to IR in a schedule- and dose-dependent manner, correlating with mitotic arrest. Radiosensitization was evidenced by decreased clonogenic survival and increased DNA double-strand breaks in irradiated cells treated with MMAE. MMAE in combination with IR resulted in increased DNA damage signaling and activation of CHK1. To test a therapeutic strategy of MMAE and IR, PANC-1 or HCT-116 murine tumor xenografts were treated with nontargeted free MMAE or tumor-targeted MMAE (ACPP-cRGD-MMAE). While free MMAE in combination with IR resulted in tumor growth delay, tumor-targeted ACPP-cRGD-MMAE with IR produced a more robust and significantly prolonged tumor regression in xenograft models. Our studies identify MMAE as a potent radiosensitizer. Importantly, MMAE radiosensitization can be localized to tumors by targeted activatable cell-penetrating peptides.
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Affiliation(s)
- Lisa Buckel
- Department of Radiation Medicine and Applied Sciences
| | | | | | | | - Angel M Hicks
- Department of Radiation Medicine and Applied Sciences
| | | | | | | | | | - Roger Y Tsien
- Department of Pharmacology.,Howard Hughes Medical Institute
| | - Sunil J Advani
- Department of Radiation Medicine and Applied Sciences.,Center for Advanced Radiotherapy Technologies University of California San Diego
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111
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Fuchs AV, Gemmell AC, Thurecht KJ. Utilising polymers to understand diseases: advanced molecular imaging agents. Polym Chem 2015. [DOI: 10.1039/c4py01311e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This review describes how the highly tuneable size, shape and chemical functionality of polymeric molecular imaging agents provides a means to intimately probe the various mechanisms behind disease formation and behaviour.
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Affiliation(s)
- Adrian V. Fuchs
- Centre for Advanced Imaging and Australian Institute for Bioengineering and Nanotechnology
- The University of Queensland
- St Lucia
- Australia
| | - Anna C. Gemmell
- Centre for Advanced Imaging and Australian Institute for Bioengineering and Nanotechnology
- The University of Queensland
- St Lucia
- Australia
| | - Kristofer J. Thurecht
- Centre for Advanced Imaging and Australian Institute for Bioengineering and Nanotechnology
- The University of Queensland
- St Lucia
- Australia
- ARC Centre of Excellence in Bio-Nano Science and Technology
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112
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Microscopic lymph node tumor burden quantified by macroscopic dual-tracer molecular imaging. Nat Med 2014; 20:1348-53. [PMID: 25344739 PMCID: PMC4224611 DOI: 10.1038/nm.3732] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 07/03/2014] [Indexed: 12/24/2022]
Abstract
Lymph node biopsy (LNB) is employed in many cancer surgeries to identify metastatic disease and stage the cancer, yet morbidity and diagnostic delays associated with LNB could be avoided if non-invasive imaging of nodal involvement was reliable. Molecular imaging has potential in this regard; however, variable delivery and nonspecific uptake of imaging tracers has made conventional approaches ineffective clinically. A method of correcting for non-specific uptake with injection of a second untargeted tracer is presented, allowing tumor burden in lymph nodes to be quantified. The approach was confirmed in an athymic mouse model of metastatic human breast cancer targeting epidermal growth factor receptor, a cell surface receptor overexpressed by many cancers. A significant correlation was observed between in vivo (dual-tracer) and ex vivo measures of tumor burden (r = 0.97, p < 0.01), with an ultimate sensitivity of approximately 200 cells (potentially more sensitive than conventional LNB).
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113
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Metildi CA, Felsen CN, Savariar EN, Nguyen QT, Kaushal S, Hoffman RM, Tsien RY, Bouvet M. Ratiometric activatable cell-penetrating peptides label pancreatic cancer, enabling fluorescence-guided surgery, which reduces metastases and recurrence in orthotopic mouse models. Ann Surg Oncol 2014; 22:2082-7. [PMID: 25319581 PMCID: PMC4400250 DOI: 10.1245/s10434-014-4144-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Indexed: 11/18/2022]
Abstract
BACKGROUND The aim of this study was to evaluate the efficacy of using matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9)-cleavable ratiometric activatable cell-penetrating peptides (RACPPs) conjugated to Cy5 and Cy7 fluorophores to accurately label pancreatic cancer for fluorescence-guided surgery (FGS) in an orthotopic mouse model. METHODS Orthotopic mouse models were established using MiaPaCa-2-GFP human pancreatic cancer cells. Two weeks after implantation, tumor-bearing mice were randomized to conventional white light reflectance (WLR) surgery or FGS. FGS was performed at far-red and infrared wavelengths with a customized fluorescence-dissecting microscope 2 h after injection of MMP-2 and MMP-9-cleavable RACPPs. Green fluorescence imaging of the GFP-labeled cancer cells was used to assess the effectiveness of surgical resection and monitor recurrence. At 8 weeks, mice were sacrificed to evaluate tumor burden and metastases. RESULTS Mice in the WLR group had larger primary tumors than mice in the FGS group at termination [1.72 g ± standard error (SE) 0.58 vs. 0.25 g ± SE 0.14; respectively, p = 0.026). Mean disease-free survival was significantly lengthened from 5.33 weeks in the WLR group to 7.38 weeks in the FGS group (p = 0.02). Recurrence rates were lower in the FGS group than in the WLR group (38 vs. 73 %; p = 0.049). This translated into lower local and distant recurrence rates for FGS compared to WLR (31 vs. 67 for local recurrence, respectively, and 25 vs. 60 % for distant recurrence, respectively). Metastatic tumor burden was significantly greater in the WLR group than in the FGS group (96.92 mm(2) ± SE 52.03 vs. 2.20 mm(2) ± SE 1.43; respectively, χ (2) = 5.455; p = 0.02). CONCLUSIONS RACPPs can accurately and effectively label pancreatic cancer for effective FGS, resulting in better postresection outcomes than for WLR surgery.
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Affiliation(s)
- Cristina A Metildi
- Department of Surgery, University of California San Diego, San Diego, CA, USA
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114
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Hauff SJ, Raju SC, Orosco RK, Gross AM, Diaz-Perez JA, Savariar E, Nashi N, Hasselman J, Whitney M, Myers JN, Lippman SM, Tsien RY, Ideker T, Nguyen QT. Matrix-metalloproteinases in head and neck carcinoma-cancer genome atlas analysis and fluorescence imaging in mice. Otolaryngol Head Neck Surg 2014; 151:612-8. [PMID: 25091190 PMCID: PMC4469264 DOI: 10.1177/0194599814545083] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 07/07/2014] [Indexed: 12/22/2022]
Abstract
OBJECTIVE (1) Obtain matrix-metalloproteinase (MMP) expression profiles for head and neck squamous cell carcinoma (HNSCC) specimens from the Cancer Genomic Atlas (TCGA). (2) Demonstrate HNSCC imaging using MMP-cleavable, fluorescently labeled ratiometric activatable cell-penetrating peptide (RACPP). STUDY DESIGN Retrospective human cohort study; prospective animal study. SETTING Translational research laboratory. SUBJECTS AND METHODS Patient clinical data and mRNA expression levels of MMP genes were downloaded from TCGA data portal. RACPP provides complementary ratiometric fluorescent contrast (increased Cy5 and decreased Cy7 intensities) when cleaved by MMP2/9. HNSCC-tumor bearing mice were imaged in vivo after RACPP injection. Histology was evaluated by a pathologist blinded to experimental conditions. Zymography confirmed MMP-2/9 activity in xenografts. RACPP was applied to homogenized human HNSCC specimens, and ratiometric fluorescent signal was measured on a microplate reader for ex vivo analysis. RESULTS Expression of multiple MMPs including MMP2/9 is greater in patient HNSCC tumors than matched control tissue. In patients with human papilloma virus positive (HPV+) tumors, higher MMP2 and MMP14 expression correlates with worse 5-year survival. Orthotopic tongue HNSCC xenografts showed excellent ratiometric fluorescent labeling with MMP2/9-cleavable RACPP (sensitivity = 95.4%, specificity = 95.0%). Fluorescence ratios were greater in areas of higher tumor burden (P < .03), which is useful for intraoperative margin assessment. Ex vivo, human HNSCC specimens showed greater cleavage of RACPP when compared to control tissue (P = .009). CONCLUSIONS Human HNSCC tumors show increased mRNA expression of multiple MMPs including MMP2/9. We used RACPP, a ratiometric fluorescence assay of MMP2/9 activity, to show improved occult tumor identification and margin clearance. Ex vivo assays using RACPP in biopsy specimens may identify patients who will benefit from intraoperative RACPP use.
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Affiliation(s)
- Samantha J Hauff
- Division of Head and Neck Surgery, University of California, San Diego, California, USA
| | - Sharat C Raju
- Division of Head and Neck Surgery, University of California, San Diego, California, USA
| | - Ryan K Orosco
- Division of Head and Neck Surgery, University of California, San Diego, California, USA
| | - Andrew M Gross
- Bioinformatics and Systems Biology Program, University of California, San Diego, California, USA
| | - Julio A Diaz-Perez
- Division of Head and Neck Surgery, University of California, San Diego, California, USA
| | - Elamprakash Savariar
- Department of Pharmacology, University of California, San Diego, California, USA
| | - Nadia Nashi
- Division of Head and Neck Surgery, University of California, San Diego, California, USA
| | - Jonathan Hasselman
- Division of Head and Neck Surgery, University of California, San Diego, California, USA
| | - Michael Whitney
- Department of Pharmacology, University of California, San Diego, California, USA
| | - Jeffrey N Myers
- Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Scott M Lippman
- Moores Cancer Center, University of California, San Diego, California, USA
| | - Roger Y Tsien
- Department of Pharmacology, University of California, San Diego, California, USA Howard Hughes Medical Institute, San Diego, California, USA
| | - Trey Ideker
- Bioinformatics and Systems Biology Program, University of California, San Diego, California, USA Division of Medical Genetics, University of California, San Diego, California, USA
| | - Quyen T Nguyen
- Division of Head and Neck Surgery, University of California, San Diego, California, USA Moores Cancer Center, University of California, San Diego, California, USA
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115
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Zhu B, Rasmussen JC, Sevick-Muraca EM. A matter of collection and detection for intraoperative and noninvasive near-infrared fluorescence molecular imaging: to see or not to see? Med Phys 2014; 41:022105. [PMID: 24506637 DOI: 10.1118/1.4862514] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Although fluorescence molecular imaging is rapidly evolving as a new combinational drug/device technology platform for molecularly guided surgery and noninvasive imaging, there remains no performance standards for efficient translation of "first-in-humans" fluorescent imaging agents using these devices. METHODS The authors employed a stable, solid phantom designed to exaggerate the confounding effects of tissue light scattering and to mimic low concentrations (nM-pM) of near-infrared fluorescent dyes expected clinically for molecular imaging in order to evaluate and compare the commonly used charge coupled device (CCD) camera systems employed in preclinical studies and in human investigational studies. RESULTS The results show that intensified CCD systems offer greater contrast with larger signal-to-noise ratios in comparison to their unintensified CCD systems operated at clinically reasonable, subsecond acquisition times. CONCLUSIONS Camera imaging performance could impact the success of future "first-in-humans" near-infrared fluorescence imaging agent studies.
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Affiliation(s)
- Banghe Zhu
- Center for Molecular Imaging, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030
| | - John C Rasmussen
- Center for Molecular Imaging, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030
| | - Eva M Sevick-Muraca
- Center for Molecular Imaging, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030
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116
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Chi C, Du Y, Ye J, Kou D, Qiu J, Wang J, Tian J, Chen X. Intraoperative imaging-guided cancer surgery: from current fluorescence molecular imaging methods to future multi-modality imaging technology. Theranostics 2014; 4:1072-84. [PMID: 25250092 PMCID: PMC4165775 DOI: 10.7150/thno.9899] [Citation(s) in RCA: 260] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 07/31/2014] [Indexed: 12/20/2022] Open
Abstract
Cancer is a major threat to human health. Diagnosis and treatment using precision medicine is expected to be an effective method for preventing the initiation and progression of cancer. Although anatomical and functional imaging techniques such as radiography, computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) have played an important role for accurate preoperative diagnostics, for the most part these techniques cannot be applied intraoperatively. Optical molecular imaging is a promising technique that provides a high degree of sensitivity and specificity in tumor margin detection. Furthermore, existing clinical applications have proven that optical molecular imaging is a powerful intraoperative tool for guiding surgeons performing precision procedures, thus enabling radical resection and improved survival rates. However, detection depth limitation exists in optical molecular imaging methods and further breakthroughs from optical to multi-modality intraoperative imaging methods are needed to develop more extensive and comprehensive intraoperative applications. Here, we review the current intraoperative optical molecular imaging technologies, focusing on contrast agents and surgical navigation systems, and then discuss the future prospects of multi-modality imaging technology for intraoperative imaging-guided cancer surgery.
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117
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Reissmann S. Cell penetration: scope and limitations by the application of cell-penetrating peptides. J Pept Sci 2014; 20:760-84. [DOI: 10.1002/psc.2672] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 06/06/2014] [Accepted: 06/10/2014] [Indexed: 12/23/2022]
Affiliation(s)
- Siegmund Reissmann
- Friedrich Schiller University, Biological and Pharmaceutical Faculty; Institute of Biochemistry and Biophysics; Dornburger Strasse 25 07743 Jena Germany
- Jena Bioscience GmbH; Loebstedter Strasse 80 07749 Jena Germany
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118
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Luke GP, Myers JN, Emelianov SY, Sokolov KV. Sentinel lymph node biopsy revisited: ultrasound-guided photoacoustic detection of micrometastases using molecularly targeted plasmonic nanosensors. Cancer Res 2014; 74:5397-408. [PMID: 25106426 DOI: 10.1158/0008-5472.can-14-0796] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metastases rather than primary tumors are responsible for killing most patients with cancer. Cancer cells often invade regional lymph nodes (LN) before colonizing other parts of the body. However, due to the low sensitivity and specificity of current imaging methods to detect localized nodal spread, an invasive surgical procedure--sentinel LN biopsy--is generally used to identify metastatic cancer cells. Here, we introduce a new approach for more sensitive in vivo detection of LN micrometastases, based on the use of ultrasound-guided spectroscopic photoacoustic (sPA) imaging of molecularly activated plasmonic nanosensors (MAPS). Using a metastatic murine model of oral squamous cell carcinoma, we showed that MAPS targeted to the epidermal growth factor receptor shifted their optical absorption spectrum to the red-near-infrared region after specific interactions with nodal metastatic cells, enabling their noninvasive detection by sPA. Notably, LN metastases as small as 50 μm were detected at centimeter-depth range with high sensitivity and specificity. Large sPA signals appeared in metastatic LN within 30 minutes of MAPS injection, in support of the clinical utility of this method. Our findings offer a rapid and effective tool to noninvasively identify micrometastases as an alternate to sentinal node biopsy analysis.
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Affiliation(s)
- Geoffrey P Luke
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas. Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas
| | - Jeffrey N Myers
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Stanislav Y Emelianov
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas. Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas. Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
| | - Konstantin V Sokolov
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas. Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
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119
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Ho ML, Judd J, Kuypers BE, Yamagami M, Wong FF, Suh J. Efficiency of Protease-Activatable Virus Nanonodes Tuned Through Incorporation of Wild-Type Capsid Subunits. Cell Mol Bioeng 2014. [DOI: 10.1007/s12195-014-0334-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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120
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Judd J, Ho ML, Tiwari A, Gomez EJ, Dempsey C, Van Vliet K, Igoshin OA, Silberg JJ, Agbandje-McKenna M, Suh J. Tunable protease-activatable virus nanonodes. ACS NANO 2014; 8:4740-6. [PMID: 24796495 PMCID: PMC4046807 DOI: 10.1021/nn500550q] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/30/2014] [Indexed: 05/19/2023]
Abstract
We explored the unique signal integration properties of the self-assembling 60-mer protein capsid of adeno-associated virus (AAV), a clinically proven human gene therapy vector, by engineering proteolytic regulation of virus-receptor interactions such that processing of the capsid by proteases is required for infection. We find the transfer function of our engineered protease-activatable viruses (PAVs), relating the degree of proteolysis (input) to PAV activity (output), is highly nonlinear, likely due to increased polyvalency. By exploiting this dynamic polyvalency, in combination with the self-assembly properties of the virus capsid, we show that mosaic PAVs can be constructed that operate under a digital AND gate regime, where two different protease inputs are required for virus activation. These results show viruses can be engineered as signal-integrating nanoscale nodes whose functional properties are regulated by multiple proteolytic signals with easily tunable and predictable response surfaces, a promising development toward advanced control of gene delivery.
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Affiliation(s)
- Justin Judd
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
| | - Michelle L. Ho
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
| | - Abhinav Tiwari
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
| | - Eric J. Gomez
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
| | - Christopher Dempsey
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
| | - Kim Van Vliet
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida 32611, United States
| | - Oleg A. Igoshin
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
| | - Jonathan J. Silberg
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
| | - Mavis Agbandje-McKenna
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida 32611, United States
| | - Junghae Suh
- Department of Bioengineering and Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States
- Address correspondence to
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121
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van Duijnhoven SMJ, Robillard MS, Nicolay K, Grüll H. In vivo biodistribution of radiolabeled MMP-2/9 activatable cell-penetrating peptide probes in tumor-bearing mice. CONTRAST MEDIA & MOLECULAR IMAGING 2014; 10:59-66. [PMID: 24823643 DOI: 10.1002/cmmi.1605] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Revised: 03/05/2014] [Accepted: 03/20/2014] [Indexed: 01/12/2023]
Abstract
Matrix metalloproteinases (MMPs) play a pivotal role in cancer progression and present therefore an interesting biomarker for early diagnosis, staging and therapy evaluation. Consequently, MMP-specific molecular imaging probes have been proposed for noninvasive visualization and quantification of MMP activity. An interesting approach is MMP-2/9 activatable cell-penetrating peptides (ACPP) that accumulate in the tumor tissue after activation. However, a recent study revealed that probe activation occurred already in the vasculature followed by nonspecific tumor targeting. In the latter study, biodistribution was determined 6 and 24 h post-ACPP injection. An alternative explanation could still be that the kinetics of tumor-specific activation is faster than that of blood activation plus subsequent nonspecific uptake in tumor. The aim of this study was to assess if tumor-specific ACPP activation occurs in mice with MMP-2/9 positive subcutaneous HT-1080 tumors at 3 h post-injection. As control, we studied the MMP-2/9 sensitive ACPP in mice bearing subcutaneous BT-20 tumors with low MMP-2/9 expression to test if probe cleavage correlates with tumoral MMP expression. Ex vivo biodistribution showed no improved tumoral ACPP activation in HT-1080 tumor-bearing mice at 3 h post-injection compared with previous reported data collected at 24 h post-injection. Furthermore, tumoral uptake and relative tumoral activation for ACPP were similar in both BT-20 and HT-1080 tumor-bearing mice. In conclusion, this study suggests that tumoral ACPP uptake in these tumor models originates from probe activation in the vasculature instead of tumor-specific MMP activation. Novel ACPPs that target tissue-specific proteases without nonspecific activation may unleash the full potential of the elegant ACPP concept.
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Affiliation(s)
- Sander M J van Duijnhoven
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands; Center for Imaging Research and Education, Eindhoven, The Netherlands
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122
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Montrose K, Yang Y, Krissansen GW. The tetrapeptide core of the carrier peptide Xentry is cell-penetrating: novel activatable forms of Xentry. Sci Rep 2014; 4:4900. [PMID: 24811205 PMCID: PMC4014984 DOI: 10.1038/srep04900] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 04/10/2014] [Indexed: 12/12/2022] Open
Abstract
Here we describe a structure-function analysis of the cell-penetrating peptide Xentry derived from the X-protein of the hepatitis B virus. Remarkably, the tetrapeptide core LCLR retains the cell-penetrating ability of the parental peptide LCLRPVG, as either an L- or D-enantiomer. Substitution of the cysteine with leucine revealed that the cysteine is essential for activity. In contrast, the C-terminal arginine could be substituted in the L-isomer with lysine, histidine, glutamic acid, glutamine, and asparagine, though the resulting peptides displayed distinct cell-type-specific uptake. Substitution of the leucines in the D-isomer with other hydrophobic residues revealed that leucines are optimal for activity. Surprisingly, linear di- and tetra-peptide forms of Xentry are not cell-permeable. Protease-activatable forms of Xentry were created by fusing Xentry to itself via a protease-cleavable peptide, or by attaching a heparin mimic peptide to the N-terminus. These novel activatable forms of Xentry were only taken up by MCF-7 cells after cleavage by matrix metalloproteinase 9, and could be used to deliver drugs specifically to tumours.
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Affiliation(s)
- Kristopher Montrose
- Department of Molecular Medicine & Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1005, New Zealand
| | - Yi Yang
- Department of Molecular Medicine & Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1005, New Zealand
| | - Geoffrey W Krissansen
- Department of Molecular Medicine & Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1005, New Zealand
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123
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Crisp JL, Savariar EN, Glasgow HL, Ellies LG, Whitney MA, Tsien RY. Dual targeting of integrin αvβ3 and matrix metalloproteinase-2 for optical imaging of tumors and chemotherapeutic delivery. Mol Cancer Ther 2014; 13:1514-25. [PMID: 24737028 DOI: 10.1158/1535-7163.mct-13-1067] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Activatable cell-penetrating peptides (ACPP) provide a general strategy for molecular targeting by exploiting the extracellular protease activities associated with disease. Previous work used a matrix metalloproteinase (MMP-2 and 9)-cleavable sequence in the ACPP to target contrast agents for tumor imaging and fluorescence-guided surgery. To improve specificity and sensitivity for MMP-2, an integrin α(v)β(3)-binding domain, cyclic-RGD, was covalently linked to the ACPP. This co-targeting strategy relies on the interaction of MMP-2 with integrin α(v)β(3), which are known to associate via the hemopexin domain of MMP-2. In U87MG glioblastoma cells in culture, dual targeting greatly improved ACPP uptake compared with either MMP or integrin α(v)β(3) targeting alone. In vivo, dual-targeted ACPP treatment resulted in tumor contrast of 7.8 ± 1.6, a 10-fold higher tumor fluorescence compared with the negative control peptide, and increased probe penetration into the core of MDA-MB-231 tumors. This platform also significantly improved efficacy of the chemotherapeutic monomethylauristatin E (MMAE) in both MDA-MB-231 orthotopic human and syngeneic Py230 murine breast tumors. Treatment with cyclic-RGD-PLGC(Me)AG-MMAE-ACPP resulted in complete tumor regression in one quarter of MDA-MB-231 tumor-bearing mice, compared with no survival in the control groups. This rational mechanism for amplified delivery of imaging and potent chemotherapeutic agents avoids the use of antibodies and may be of considerable generality.
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Affiliation(s)
- Jessica L Crisp
- Authors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, Maryland
| | - Elamprakash N Savariar
- Authors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, Maryland
| | - Heather L Glasgow
- Authors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, MarylandAuthors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, Maryland
| | - Lesley G Ellies
- Authors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, Maryland
| | - Michael A Whitney
- Authors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, Maryland
| | - Roger Y Tsien
- Authors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, MarylandAuthors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, MarylandAuthors' Affiliations: Departments of Pharmacology, Pathology, and Chemistry and Biochemistry, Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California; and Howard Hughes Medical Institute, Bethesda, Maryland
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124
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De la Garza-Ramos R, Bydon M, Macki M, Huang J, Tamargo RJ, Bydon A. Fluorescent techniques in spine surgery. Neurol Res 2014; 36:928-38. [DOI: 10.1179/1743132814y.0000000340] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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125
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Felsen CN, Savariar EN, Whitney M, Tsien RY. Detection and monitoring of localized matrix metalloproteinase upregulation in a murine model of asthma. Am J Physiol Lung Cell Mol Physiol 2014; 306:L764-74. [PMID: 24508733 DOI: 10.1152/ajplung.00371.2013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Extracellular proteases including matrix metalloproteinases (MMPs) are speculated to play a significant role in chronic lung diseases, such as asthma. Although increased protease expression has been correlated with lung pathogenesis, the relationship between localized enzyme activity and disease progression remains poorly understood. We report the application of MMP-2/9 activatable cell-penetrating peptides (ACPPs) and their ratiometric analogs (RACPPs) for in vivo measurement of protease activity and distribution in the lungs of mice that were challenged with the allergen ovalbumin. MMP-2/9 activity was increased greater than twofold in whole, dissected lungs from acutely challenged mice compared with control mice (P=1.8×10(-4)). This upregulation of MMP-2/9 activity was localized around inflamed airways with 1.6-fold higher protease-dependent ACPP uptake surrounding diseased airways compared with adjacent, pathologically normal lung parenchyma (P=0.03). MMP-2/9 activity detected by ACPP cleavage colocalized with gelatinase activity measured with in situ dye-quenched gelatin. For comparison, neutrophil elastase activity and thrombin activity, detected with elastase- and thrombin-cleavable RACPPs, respectively, were not significantly elevated in acutely allergen-challenged mouse lungs. The results demonstrate that ACPPs, like the MMP-2/9-activated and related ACPPs, allow for real-time detection of protease activity in a murine asthma model, which should improve our understanding of protease activation in asthma disease progression and help elucidate new therapy targets or act as a mechanism for therapeutic drug delivery.
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Affiliation(s)
- Csilla N Felsen
- Howard Hughes Medical Institute, Univ. California San Diego, 9500 Gilman Dr., George Palade 310, La Jolla, CA 92093-0647.
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126
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Lin IT, Tsai YL, Kang CC, Huang WC, Wang CL, Lin MY, Lou PJ, Shih JY, Wang HC, Wu HD, Tsai TH, Jan IS, Chang TC. BMVC test, an improved fluorescence assay for detection of malignant pleural effusions. Cancer Med 2014; 3:162-73. [PMID: 24408009 PMCID: PMC3930401 DOI: 10.1002/cam4.179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 10/31/2013] [Accepted: 11/25/2013] [Indexed: 01/05/2023] Open
Abstract
The diagnosis of malignant pleural effusions is an important issue in the management of malignancy patients. Generally, cytologic examination is a routine diagnostic technique. However, morphological interpretation of cytology is sometimes inconclusive. Here an ancillary method named BMVC test is developed for rapid detection of malignant pleural effusion to improve the diagnostic accuracy at low cost. A simple assay kit is designed to collect living cells from clinical pleural effusion and a fluorescence probe, 3,6-Bis(1-methyl-4-vinylpyridinium) carbazole diiodide (BMVC), is used to illuminate malignant cells. The fluorescence intensity is quantitatively analyzed by ImageJ program. This method yields digital numbers for the test results without any grey zone or ambiguities in the current cytology tests due to intra-observer and inter-observer variability. Comparing with results from double-blind cytologic examination, this simple test gives a good discrimination between malignant and benign specimens with sensitivity of 89.4% (42/47) and specificity of 93.3% (56/60) for diagnosis of malignant pleural effusion. BMVC test provides accurate results in a short time period, and the digital output could assist cytologic examination to become more objective and clear-cut. This is a convenient ancillary tool for detection of malignant pleural effusions.
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Affiliation(s)
- I-Ting Lin
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 106, Taiwan
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127
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Weinstain R, Savariar EN, Felsen CN, Tsien RY. In vivo targeting of hydrogen peroxide by activatable cell-penetrating peptides. J Am Chem Soc 2014; 136:874-7. [PMID: 24377760 PMCID: PMC3929323 DOI: 10.1021/ja411547j] [Citation(s) in RCA: 181] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A hydrogen peroxide (H2O2)-activated cell-penetrating peptide was developed through incorporation of a boronic acid-containing cleavable linker between polycationic cell-penetrating peptide and polyanionic fragments. Fluorescence labeling of the two ends of the molecule enabled monitoring its reaction with H2O2 through release of the highly adhesive cell-penetrating peptide and disruption of fluorescence resonance energy transfer. The H2O2 sensor selectively reacts with endogenous H2O2 in cell culture to monitor the oxidative burst of promyelocytes and in vivo to image lung inflammation. Targeting H2O2 has potential applications in imaging and therapy of diseases related to oxidative stress.
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Affiliation(s)
- Roy Weinstain
- Department of Pharmacology, ‡Department of Chemistry and Biochemistry, and §Howard Hughes Medical Institute, University of California San Diego , La Jolla, California 92093, United States
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128
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Ma X, Cheng Z, Jin Y, Liang X, Yang X, Dai Z, Tian J. SM5-1-conjugated PLA nanoparticles loaded with 5-fluorouracil for targeted hepatocellular carcinoma imaging and therapy. Biomaterials 2014; 35:2878-89. [PMID: 24411331 DOI: 10.1016/j.biomaterials.2013.12.045] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 12/18/2013] [Indexed: 12/19/2022]
Abstract
SM5-1 is a humanized mouse antibody which has a high binding specificity for a membrane protein of about 230 kDa overexpressed in hepatocellular carcinoma (HCC), melanoma and breast cancer. In this study, SM5-1-conjugated poly D, L (lactide-coglycolide) (PLA) PLA containing Cy7 (PLA-Cy7-SM5-1) was prepared to study the targeting specificity of the bioconjugate to HCC-LM3-fLuc cell. Then, SM5-1-conjugated PLA containing 5-fluorouracil (5-FU) (PLA-5FU-SM5-1) and PLA containing 5-FU (PLA-5FU) were prepared for treatment of subcutaneous HCC-LM3-fLuc tumor mice. The results showed that PLA-5FU-SM5-1, PLA-5FU and 5-FU induced a 45.07%, 23.56% and 19.05% tumor growth inhibition rate, respectively, on day 31 post-treatment as determined by bioluminescent intensity. In addition, in order to evaluate the antitumor efficacy of PLA-5FU-SM5-1, HCC-LM3-fLuc cells were injected into the liver to establish the experimental orthotopic liver tumor models. The experiments showed that PLA-5FU-SM5-1, PLA-5FU and 5-FU induced a 53.24%, 31.00%, and 18.11% tumor growth inhibition rate, respectively, on day 31 post-treatment determined by the bioluminescent intensity of the abdomen in tumor-bearing mice. Furthermore, we have calculated the three-dimensional location of the liver cancer in mice using a multilevel adaptive finite element algorithm based on bioluminescent intensity decay calibration. The reconstruction results demonstrated that PLA-5FU-SM5-1 inhibited the tumor rapid progression, which were consistent with the results of subcutaneous tumor mice experiments and in vitro cell experiment results.
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Affiliation(s)
- Xibo Ma
- Key Laboratory of Molecular Imaging of Chinese Academy of Sciences, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhen Cheng
- Molecular Imaging Program at Stanford (MIPS), Bio-X Program, Department of Radiology, Stanford University, California 94305-5344, USA
| | - Yushen Jin
- Nanomedicine and Biosensor Laboratory, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150080, China
| | - Xiaolong Liang
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing, China
| | - Xin Yang
- Key Laboratory of Molecular Imaging of Chinese Academy of Sciences, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhifei Dai
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing, China
| | - Jie Tian
- Key Laboratory of Molecular Imaging of Chinese Academy of Sciences, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China.
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129
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Zhu B, Wu G, Robinson H, Wilganowski N, Hall MA, Ghosh SC, Pinkston KL, Azhdarinia A, Harvey BR, Sevick-Muraca EM. Tumor margin detection using quantitative NIRF molecular imaging targeting EpCAM validated by far red gene reporter iRFP. Mol Imaging Biol 2013; 15:560-8. [PMID: 23619897 DOI: 10.1007/s11307-013-0637-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE Wide-field surgical excision reduces the chance of residual disease, but can also lead to disfigurement and devastating morbidities when resection is close to critical structures. We hypothesize that near-infrared fluorescence (NIRF) imaging can enable accurate detection of tumor margins for image-guided resection. EXPERIMENTAL DESIGN An orthotopic model of human prostate cancer (PCa) was used to assess primary tumor margins using a NIRF-labeled antibody against epithelial cell adhesion molecule (EpCAM). PCa cells stably expressing far red fluorescent gene reporter, iRFP, enabled colocalization with NIRF signals for direct assessment of tumor margins. RESULTS Using receiver operating characteristic analysis, far red fluorescence was validated against standard pathology of primary and metastatic lesions with >96 % accuracy. Primary tumor margins were more accurately detected by quantitative NIRF imaging using the EpCAM-targeting antibody as compared to a NIRF-labeled isotype control antibody. CONCLUSIONS NIRF molecular imaging may enable real-time and accurate assessment of tumor margins.
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Affiliation(s)
- Banghe Zhu
- Center for Molecular Imaging, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, 1825 Pressler Street, Houston, TX, 77030, USA
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130
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Abstract
A glowing new era in cancer surgery may be dawning. Using fluorescently labelled markers, surgical molecular navigation means that tumours and nerves can be displayed in real time intra-operatively in contrasting pseudocolours, which allows more complete tumour resection while preserving important structures. These advances can potentially cause a paradigm shift in cancer surgery, improving patient outcome and decreasing overall health-care costs.
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Affiliation(s)
- Quyen T. Nguyen
- The Division of Otolaryngology — Head and Neck Surgery, University of California at San Diego, La Jolla, California 92093–0647, USA
| | - Roger Y. Tsien
- The Department of Pharmacology, Howard Hughes Medical Institute, University of California at San Diego, La Jolla, California 92093–0647, USA
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131
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Very long-term memories may be stored in the pattern of holes in the perineuronal net. Proc Natl Acad Sci U S A 2013; 110:12456-61. [PMID: 23832785 DOI: 10.1073/pnas.1310158110] [Citation(s) in RCA: 172] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A hypothesis and the experiments to test it propose that very long-term memories, such as fear conditioning, are stored as the pattern of holes in the perineuronal net (PNN), a specialized ECM that envelops mature neurons and restricts synapse formation. The 3D intertwining of PNN and synapses would be imaged by serial-section EM. Lifetimes of PNN vs. intrasynaptic components would be compared with pulse-chase (15)N labeling in mice and (14)C content in human cadaver brains. Genetically encoded indicators and antineoepitope antibodies should improve spatial and temporal resolution of the in vivo activity of proteases that locally erode PNN. Further techniques suggested include genetic KOs, better pharmacological inhibitors, and a genetically encoded snapshot reporter, which will capture the pattern of activity throughout a large ensemble of neurons at a time precisely defined by the triggering illumination, drive expression of effector genes to mark those cells, and allow selective excitation, inhibition, or ablation to test their functional importance. The snapshot reporter should enable more precise inhibition or potentiation of PNN erosion to compare with behavioral consequences. Finally, biosynthesis of PNN components and proteases would be imaged.
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132
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Abstract
The ability of cell-penetrating peptides to cross plasma membranes has been used for various applications, including the delivery of bioactive molecules to inhibit disease-producing cellular mechanisms. Selective drug delivery into target cells improves drug distribution and decreases dosing and toxicity. In this review, the authors outline the main challenges in the field, namely clarification of mechanisms of entry into cells, as well as current and future perspectives regarding cell-penetrating peptides application for human therapeutics. Here, the authors discuss some of the factors that influence efficacy of delivery and review the current status of preclinical studies and clinical trials involving the use of cell-penetrating peptide-mediated delivery of therapeutics.
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133
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Abstract
Although the modern surgical era is highlighted by multiple technological advances and innovations, one area that has remained constant is the dependence of the surgeon's vision on white-light reflectance. This renders different body tissues in a limited palette of various shades of pink and red, thereby limiting the visual contrast available to the operating surgeon. Healthy tissue, anatomic variations, and diseased states are seen as slight discolorations relative to each other and differences are inherently limited in dynamic range. In the upcoming years, surgery will undergo a paradigm shift with the use of targeted fluorescence imaging probes aimed at augmenting the surgical armamentarium by expanding the "visible" spectrum available to surgeons. Such fluorescent "smart probes" will provide real-time, intraoperative, pseudo-color, high-contrast delineation of both normal and pathologic tissues. Fluorescent surgical molecular guidance promises another major leap forward to improve patient safety and clinical outcomes, and to reduce overall healthcare costs. This review provides an overview of current and future surgical applications of fluorescence imaging in diseased and nondiseased tissues and focus on the innovative fields of image processing and instrumentation.
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Affiliation(s)
- Ryan K Orosco
- Division of Head and Neck Surgery, University of California San Diego, La Jolla, CA 92093-0647, USA
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134
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Chi C, Ye J, Ding H, He D, Huang W, Zhang GJ, Tian J. Use of indocyanine green for detecting the sentinel lymph node in breast cancer patients: from preclinical evaluation to clinical validation. PLoS One 2013; 8:e83927. [PMID: 24358319 PMCID: PMC3865279 DOI: 10.1371/journal.pone.0083927] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 11/10/2013] [Indexed: 02/05/2023] Open
Abstract
Assessment of the sentinel lymph node (SLN) in patients with early stage breast cancer is vital in selecting the appropriate surgical approach. However, the existing methods, including methylene blue and nuclides, possess low efficiency and effectiveness in mapping SLNs, and to a certain extent exert side effects during application. Indocyanine green (ICG), as a fluorescent dye, has been proved reliable usage in SLN detection by several other groups. In this paper, we introduce a novel surgical navigation system to detect SLN with ICG. This system contains two charge-coupled devices (CCD) to simultaneously capture real-time color and fluorescent video images through two different bands. During surgery, surgeons only need to follow the fluorescence display. In addition, the system saves data automatically during surgery enabling surgeons to find the registration point easily according to image recognition algorithms. To test our system, 5 mice and 10 rabbits were used for the preclinical setting and 22 breast cancer patients were utilized for the clinical evaluation in our experiments. The detection rate was 100% and an average of 2.7 SLNs was found in 22 patients. Our results show that the usage of our surgical navigation system with ICG to detect SLNs in breast cancer patients is technically feasible.
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Affiliation(s)
- Chongwei Chi
- Intelligent Medical Research Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Jinzuo Ye
- Intelligent Medical Research Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Haolong Ding
- The Breast Center, Cancer Hospital, Shantou University Medical College, Shantou, China
| | - De He
- The Breast Center, Cancer Hospital, Shantou University Medical College, Shantou, China
| | - Wenhe Huang
- The Breast Center, Cancer Hospital, Shantou University Medical College, Shantou, China
| | - Guo-Jun Zhang
- The Breast Center, Cancer Hospital, Shantou University Medical College, Shantou, China
- * E-mail: (GJZ); (JT)
| | - Jie Tian
- Intelligent Medical Research Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
- * E-mail: (GJZ); (JT)
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135
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Whitney M, Savariar EN, Friedman B, Levin RA, Crisp JL, Glasgow HL, Lefkowitz R, Adams SR, Steinbach P, Nashi N, Nguyen QT, Tsien RY. Ratiometric activatable cell-penetrating peptides provide rapid in vivo readout of thrombin activation. Angew Chem Int Ed Engl 2012; 52:325-30. [PMID: 23080482 PMCID: PMC3694763 DOI: 10.1002/anie.201205721] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 09/01/2012] [Indexed: 01/10/2023]
Affiliation(s)
- Michael Whitney
- Department of Pharmacology, UCSD School of Medicine, University of California San Diego, La Jolla, USA
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