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Antibody-Based Immunotherapy: Alternative Approaches for the Treatment of Metastatic Melanoma. Biomedicines 2020; 8:biomedicines8090327. [PMID: 32899183 PMCID: PMC7555584 DOI: 10.3390/biomedicines8090327] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/28/2020] [Accepted: 09/01/2020] [Indexed: 12/13/2022] Open
Abstract
Melanoma is the least common form of skin cancer and is associated with the highest mortality. Where melanoma is mostly unresponsive to conventional therapies (e.g., chemotherapy), BRAF inhibitor treatment has shown improved therapeutic outcomes. Photodynamic therapy (PDT) relies on a light-activated compound to produce death-inducing amounts of reactive oxygen species (ROS). Their capacity to selectively accumulate in tumor cells has been confirmed in melanoma treatment with some encouraging results. However, this treatment approach has not reached clinical fruition for melanoma due to major limitations associated with the development of resistance and subsequent side effects. These adverse effects might be bypassed by immunotherapy in the form of antibody–drug conjugates (ADCs) relying on the ability of monoclonal antibodies (mAbs) to target specific tumor-associated antigens (TAAs) and to be used as carriers to specifically deliver cytotoxic warheads into corresponding tumor cells. Of late, the continued refinement of ADC therapeutic efficacy has given rise to photoimmunotherapy (PIT) (a light-sensitive compound conjugated to mAbs), which by virtue of requiring light activation only exerts its toxic effect on light-irradiated cells. As such, this review aims to highlight the potential clinical benefits of various armed antibody-based immunotherapies, including PDT, as alternative approaches for the treatment of metastatic melanoma.
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Lian X, Huang Y, Zhu Y, Fang Y, Zhao R, Joseph E, Li J, Pellois JP, Zhou HC. Enzyme-MOF Nanoreactor Activates Nontoxic Paracetamol for Cancer Therapy. Angew Chem Int Ed Engl 2018; 57:5725-5730. [PMID: 29536600 PMCID: PMC6621563 DOI: 10.1002/anie.201801378] [Citation(s) in RCA: 173] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/09/2018] [Indexed: 11/08/2022]
Abstract
Prodrug activation, by exogenously administered enzymes, for cancer therapy is an approach to achieve better selectivity and less systemic toxicity than conventional chemotherapy. However, the short half-lives of the activating enzymes in the bloodstream has limited its success. Demonstrated here is that a tyrosinase-MOF nanoreactor activates the prodrug paracetamol in cancer cells in a long-lasting manner. By generating reactive oxygen species (ROS) and depleting glutathione (GSH), the product of the enzymatic conversion of paracetamol is toxic to drug-resistant cancer cells. Tyrosinase-MOF nanoreactors cause significant cell death in the presence of paracetamol for up to three days after being internalized by cells, while free enzymes totally lose activity in a few hours. Thus, enzyme-MOF nanocomposites are envisioned to be novel persistent platforms for various biomedical applications.
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Affiliation(s)
- Xizhen Lian
- Department of Chemistry, Texas A&M University, College Station, TX 77843-3255 (USA)
| | - Yanyan Huang
- Beijing National Laboratory for MolecularSciences; CAS Key, Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy Of Sciences, Beijing, 100190(China)
| | - Yuanyuan Zhu
- Beijing National Laboratory for MolecularSciences; CAS Key, Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy Of Sciences, Beijing, 100190(China)
| | - Yu Fang
- Department of Chemistry, Texas A&M University, College Station, TX 77843-3255 (USA)
| | - Rui Zhao
- Beijing National Laboratory for MolecularSciences; CAS Key, Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy Of Sciences, Beijing, 100190(China)
| | - Elizabeth Joseph
- Department of Chemistry, Texas A&M University, College Station, TX 77843-3255 (USA)
| | - Jialuo Li
- Department of Chemistry, Texas A&M University, College Station, TX 77843-3255 (USA)
| | - Jean-Philippe Pellois
- Department of Biochemistry and Biophysics, Texas A&M University College Station, TX 77843-2128 (USA); Department of Chemistry, Texas A&M University, College Station, TX 77843-3255 (USA)
| | - Hong-Cai Zhou
- Department of Chemistry, Texas A&M University, College Station, TX 77843-3255 (USA)
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Lian X, Huang Y, Zhu Y, Fang Y, Zhao R, Joseph E, Li J, Pellois JP, Zhou HC. Enzyme-MOF Nanoreactor Activates Nontoxic Paracetamol for Cancer Therapy. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201801378] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Xizhen Lian
- Department of Chemistry; Texas A&M University; College Station TX 77843-3255 USA
| | - Yanyan Huang
- Beijing National Laboratory for Molecular Sciences; CAS Key Laboratory of Analytical Chemistry for Living Biosystems; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 China
| | - Yuanyuan Zhu
- Beijing National Laboratory for Molecular Sciences; CAS Key Laboratory of Analytical Chemistry for Living Biosystems; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 China
| | - Yu Fang
- Department of Chemistry; Texas A&M University; College Station TX 77843-3255 USA
| | - Rui Zhao
- Beijing National Laboratory for Molecular Sciences; CAS Key Laboratory of Analytical Chemistry for Living Biosystems; Institute of Chemistry; Chinese Academy of Sciences; Beijing 100190 China
| | - Elizabeth Joseph
- Department of Chemistry; Texas A&M University; College Station TX 77843-3255 USA
| | - Jialuo Li
- Department of Chemistry; Texas A&M University; College Station TX 77843-3255 USA
| | - Jean-Philippe Pellois
- Department of Chemistry; Texas A&M University; College Station TX 77843-3255 USA
- Department of Biochemistry and Biophysics; Texas A&M University; College Station TX 77843-2128 USA
| | - Hong-Cai Zhou
- Department of Chemistry; Texas A&M University; College Station TX 77843-3255 USA
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Abstract
Cancer is a multifactorial disease and is one of the leading causes of death worldwide. The contributing factors include specific genetic background, chronic exposure to various environmental stresses and improper diet. All these risk factors lead to the accumulation of molecular changes or mutations in some important proteins in cells which contributes to the initiation of carcinogenesis. Chemotherapy is an effective treatment against cancer but undesirable chemotherapy reactions and the development of resistance to drugs which results in multi-drug resistance (MDR) are the major obstacles in cancer chemotherapy. Strategies which are in practice with limited success include alternative formulations e.g., liposomes, resistance modulation e.g., PSC833, antidotes/toxicity modifiers e.g., ICRF-187 and gene therapy. Targeted therapy is gaining importance due to its specificity towards cancer cells while sparing toxicity to off-target cells. The scope of this review involves the various strategies involved in targeted therapy like-monoclonal antibodies, prodrug, small molecule inhibitors and nano-particulate antibody conjugates.
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Affiliation(s)
- Viswanadha Vijaya Padma
- Department of Biotechnology, Bharathiar University, 641 046, Coimbatore, Tamil Nadu, India. .,Department of Health and Nutrition Biotechnology, Asia University, 413, Taichung, Taiwan.
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Andrady C, Sharma SK, Chester KA. Antibody-enzyme fusion proteins for cancer therapy. Immunotherapy 2011; 3:193-211. [PMID: 21322759 DOI: 10.2217/imt.10.90] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Advances in biomolecular technology have allowed the development of genetically fused antibody-enzymes. Antibody-enzyme fusion proteins have been used to target tumors for cancer therapy in two ways. In one system, an antibody-enzyme is pretargeted to the tumor followed by administration of an inactive prodrug that is converted to its active form by the pretargeted enzyme. This system has been described as antibody-directed enzyme prodrug therapy. The other system uses antibody-enzyme fusion proteins as direct therapeutics, where the enzyme is toxic in its own right. The key feature in this approach is that the antibody is used to internalize the toxic enzyme into the tumor cell, which activates cell-death processes. This antibody-enzyme system has been largely applied to deliver ribonucleases. This article addresses these two antibody-enzyme targeting strategies for cancer therapy from concept to (pre)clinical trials.
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Affiliation(s)
- Carima Andrady
- Cancer Research UK Targeting & Imaging Group, Department of Oncology, UCL Cancer Institute, Paul O'Gorman Building, University College London, 72 Huntley Street, London WC1E6BT, UK.
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Niculescu-Duvaz D, Negoita-Giras G, Niculescu-Duvaz I, Hedley D, Springer CJ. Directed Enzyme Prodrug Therapies. PRODRUGS AND TARGETED DELIVERY 2011. [DOI: 10.1002/9783527633166.ch12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Abstract
In recent years, nanoparticulate-mediated drug delivery research has examined a full spectrum of nanoparticles that can be used in diagnostic and therapeutic cancer applications. A key aspect of this technology is in the potential to specifically target the nanoparticles to diseased cells using a range of molecules, in particular antibodies. Antibody–nanoparticle conjugates have the potential to elicit effective targeting and release of therapeutic targets at the disease site, while minimizing off-target side effects caused by dosing of normal tissues. This article provides an overview of various antibody-conjugated nanoparticle strategies, focusing on the rationale of cell-surface receptors targeted and their potential clinical application.
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Affiliation(s)
- Francois Fay
- School of Pharmacy, Queen’s University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast, BT9 7BL, UK
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Wolf M, Eskerski H, Bauder-Wüst U, Haberkorn U, Eisenhut M. Alkylating benzamides with melanoma cytotoxicity: experimental chemotherapy in a mouse melanoma model. Melanoma Res 2007; 16:487-96. [PMID: 17119449 DOI: 10.1097/01.cmr.0000232294.14408.6a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The in-vivo antineoplastic potential of the alkylating N-(2-dialkylaminoethyl)benzamides BZA1 and BZA2, novel melanoma targeted anticancer drugs, was evaluated in a mouse melanoma model with nude mice bearing subcutaneous SkMel28, B16 or WM266-4. The maximal tolerated dose (MTD) for the intraperitoneal application of both agents was found to be 24 mg/kg. Treatment was initiated with an intraperitoneal injection of 8 mg/kg of BZA1 or BZA2 on days 0, 2 and 4 in the case of B16 melanoma on days 0, 1 and 2 after the onset of the experiment, when the mean tumor diameter ranged within 4-6 mm. The experiment was terminated when the mean tumor diameter in the control group had reached a value of 12 mm. Tumor growth delay of these agents was compared with dacarbazine (3x250 mg/kg), chlorambucil (3x5 mg/kg) and an untreated control group. Significant tumor growth delay was observed under BZA1, BZA2 and dacarbazine treatment compared with the untreated control group in all three evaluated melanomas with insignificant differences among BZA1, BZA2 and dacarbazine. The insignificant effect of chlorambucil and the strong improvement on growth delay achieved with BZA1 and BZA2 demonstrated melanoma targeting characteristics of the N-(2-dialkylaminoethyl)benzamide structure element. Dacarbazine was more effective in the in-vivo antineoplastic assay compared with the in-vitro cytotoxicity studies, probably due to hepatic bioactivation. Similar side effect intensity of BZA2 and dacarbazine was observed, whereas BZA1 was more toxic. BZA2 might represent an alternative antimelanoma drug, especially in patients not responding to dacarbazine.
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Affiliation(s)
- Markus Wolf
- Department of Radiopharmaceutical Chemistry, German Cancer Research Center (DKFZ), Heidelberg, Germany.
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Abstract
Antibody-directed enzyme prodrug therapy was conceived as a means of restricting the action of cytotoxic drugs to tumor sites. Since antigenic targets were a central component of the approach, colonic cancer, with its virtually universal expression of carcinoembryonic antigen at the cellular level, presented an obvious starting point. The principle of antibody-directed enzyme prodrug therapy is to use an antibody directed at a tumor-associated antigen to vector an enzyme to tumor sites. The enzyme should be retained at tumor sites after it has cleared from blood and normal tissues. A nontoxic prodrug, a substrate for the enzyme, is then given and, by cleaving an inactivating component from the prodrug, a potent cytotoxic agent is generated. One of the potential advantages of such a system is that a small cytotoxic agent, generated within a tumor site, is much more diffusible than a large antibody molecule. Moreover, failure to express the target antigen by cancer cells does not protect them from the bystander action of the cytotoxic agent. This review will primarily consider the studies of the London group since this is the only group that has so far reported clinical trials and it is only through clinical trials that the requirements of a successful antibody-directed enzyme prodrug therapy system can be identified.
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Affiliation(s)
- Kenneth D Bagshawe
- Imperial College London, Department of Medical Oncology, Charing Cross Campus, Fulham Palace Road, London W6 8RF, UK.
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Wolf M, Bauder-Wüst U, Haberkorn U, Mier W, Eisenhut M. Alkylating benzamides with melanoma cytotoxicity: role of melanin, tyrosinase, intracellular pH and DNA interaction. Melanoma Res 2006; 15:383-91. [PMID: 16179865 DOI: 10.1097/00008390-200510000-00006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
N-(2-Dialkylaminoethyl)benzamides have been shown to selectively accumulate in melanoma metastases with high uptake capacity. Therefore, this class of compound has previously been evaluated as a transporter for cytostatic drugs. It has been demonstrated that this significant targeting effect improves the cytotoxicity against melanoma cells. Although these agents are not accumulated by non-melanoma cells, they have been found to be toxic. In order to identify mechanistic reasons for this effect, we investigated the DNA and melanin binding affinities of a selection of four benzamide-drug conjugates, together with their parental cytostatics. An investigation of the influence of the melanin content on the cytotoxicity of these substances in B16 melanoma and Morris hepatoma (MH3924A) cells was performed, together with their influence on melanosomal pH and tyrosinase activity. The suppression of melanin formation with phenylisothiourea and the saturation of melanin binding sites with chloroquine were also investigated. These experiments demonstrated high DNA binding and low melanin affinity, in accordance with the toxicity against tumour cells. Melanin has a concentration-dependent scavenging effect, thereby reducing cytotoxicity. These compounds lead to an increase in the acidic pH of melanosomes, resulting in an increase in tyrosinase activity. The consequence of this reaction chain is an amplification of the scavenging effect for the benzamide-drug conjugates. These effects may be considered as limiting factors for the targeting characteristics of this class of compound, necessitating further modifications to the carrier system.
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Affiliation(s)
- Markus Wolf
- Department of Radiopharmaceutical Chemistry, German Cancer Research Center Heidelberg, Germany
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Rooseboom M, Commandeur JNM, Vermeulen NPE. Enzyme-catalyzed activation of anticancer prodrugs. Pharmacol Rev 2004; 56:53-102. [PMID: 15001663 DOI: 10.1124/pr.56.1.3] [Citation(s) in RCA: 370] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The rationale fo the development of prodrugs relies upon delivery of higher concentrations of a drug to target cells compared to administration of the drug itself. In the last decades, numerous prodrugs that are enzymatically activated into anti-cancer agents have been developed. This review describes the most important enzymes involved in prodrug activation notably with respect to tissue distribution, up-regulation in tumor cells and turnover rates. The following endogenous enzymes are discussed: aldehyde oxidase, amino acid oxidase, cytochrome P450 reductase, DT-diaphorase, cytochrome P450, tyrosinase, thymidylate synthase, thymidine phosphorylase, glutathione S-transferase, deoxycytidine kinase, carboxylesterase, alkaline phosphatase, beta-glucuronidase and cysteine conjugate beta-lyase. In relation to each of these enzymes, several prodrugs are discussed regarding organ- or tumor-selective activation of clinically relevant prodrugs of 5-fluorouracil, axazaphosphorines (cyclophosphamide, ifosfamide, and trofosfamide), paclitaxel, etoposide, anthracyclines (doxorubicin, daunorubicin, epirubicin), mercaptopurine, thioguanine, cisplatin, melphalan, and other important prodrugs such as menadione, mitomycin C, tirapazamine, 5-(aziridin-1-yl)-2,4-dinitrobenzamide, ganciclovir, irinotecan, dacarbazine, and amifostine. In addition to endogenous enzymes, a number of nonendogenous enzymes, used in antibody-, gene-, and virus-directed enzyme prodrug therapies, are described. It is concluded that the development of prodrugs has been relatively successful; however, all prodrugs lack a complete selectivity. Therefore, more work is needed to explore the differences between tumor and nontumor cells and to develop optimal substrates in terms of substrate affinity and enzyme turnover rates fo prodrug-activating enzymes resulting in more rapid and selective cleavage of the prodrug inside the tumor cells.
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Affiliation(s)
- Martijn Rooseboom
- Leiden/Amsterdam Center for Drug Research (L.A.C.D.R.), Division of Molecular Toxicology, Department of Pharmacochemistry, Vrije Universiteit Amsterdam, De Boelelaan 1083, Amsterdam, The Netherlands.
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Wolf M, Bauder-Wüst U, Mohammed A, Schönsiegel F, Mier W, Haberkorn U, Eisenhut M. Alkylating benzamides with melanoma cytotoxicity. Melanoma Res 2004; 14:353-60. [PMID: 15457090 DOI: 10.1097/00008390-200410000-00004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Radioiodinated N-(2-(diethylamino)ethyl)benzamides have recently been discovered as selective agents for melanotic melanoma and are used for scintigraphic imaging in nuclear medicine. Owing to the high binding capacity, benzamide derivatives conjugated with alkylating cytostatics were synthesized and tested for their potential for targeted drug delivery. Conjugates of chlorambucil with procainamide (1), diethylaminoethylamine (2) and 2-pyrrolidin-1-yl-ethylamine (3), as well as 4-(bis(2-chloroethyl)amino)- (6,7) and 4-(N,N-diethyltriazeno)-substituted (8-10) benzamides, were synthesized. Cell uptake studies with B16 melanoma cells revealed high uptake of radioiodinated 1 and 2, while radiolabelled chlorambucil was found to lack this characteristic. These results were confirmed by biodistribution studies in a mouse melanoma model. Viability measurements revealed that all chlorambucil-benzamide derivatives showed higher toxicity against B16 melanoma and SK-MEL-28 cells than did the parent chlorambucil itself, and that the triazene derivatives were more potent than dacarbazine, which is currently used as a standard cytostatic drug in melanoma therapy. Of all the compounds tested in this series, the triazenes 9 and 10 showed the most promising targeting effect. The toxicity of these compounds against hepatoma cells (MH3924A) and, to a lesser extent, against mouse fibroblast (NIH 3T3) and cervix carcinoma (HeLa) cells was also enhanced, but they were not as toxic as dacarbazine (HeLa). These findings support the concept of a selective, benzamide-mediated in vivo delivery of cytostatics in melanoma cells, leading to enhanced efficacy.
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Affiliation(s)
- Markus Wolf
- Department of Radiopharmaceutical Chemistry, German Cancer Research Centre Heidelberg and Department of Nuclear Medicine, University of Heidelberg, Heidelberg, Germany
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Fang J, Song JD. Construction and expression of fusion gene of single chain Fv against human colorectal carcinoma. Shijie Huaren Xiaohua Zazhi 2003; 11:289-293. [DOI: 10.11569/wcjd.v11.i3.289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the construction of the fusion gene of recombinant ND-1scFv against human colorectal carcinoma and yeast cytosine deaminase and the expression of the fusion protein in E. coli.
METHODS: Yeast cytosine deaminase gene was fused with the 3'terminus of gene of ND-1scFv against human colorectal carcinoma by a 18 bp linker with sequences encoding GSGGSG. To construct ND-1scFv-CD gene, plasmid pET 28 a(+)-ND-1scFv-CD was transformed into E. coli BL-21, and induced by IPTG to express the ND-1scFv-CD fusion protein. The expressed product was purified by affinity chromatography using NI-NTA resin, and its immunity was analyzed by ELISA. The cytotoxic activity of the ADEPT system containing ND-1 scFv-CD/5FC against human colon carcinoma cell line was evaluated by MTT assay.
RESULTS: Sequencing results showed that the ND-1scFv-CD gene consisted of 1 269 bp, including ND-1scFv 732 bp and CD 477 bp. SDS-PAGE analysis showed that the expected molecular weight of fusion protein was 47 Kd. Optical density scanning showed that fusion protein expressed in E. coli accounted to 27% of the total bacterial proteins. ELISA analysis revealed that ND-1scFv-CD reserved similar immunity of ND-1scFv. MTT assay showed scFv-CD/5FC was cytotoxic to human colorectal carcinoma cells.
CONCLUSION: ND-1scFv-CD gene against human colorectal carcinoma was constructed and expressed successfully in E. coli. The fusion protein exhibited good immunity and enzymatic activity.
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Senter PD, Springer CJ. Selective activation of anticancer prodrugs by monoclonal antibody-enzyme conjugates. Adv Drug Deliv Rev 2001; 53:247-64. [PMID: 11744170 DOI: 10.1016/s0169-409x(01)00206-x] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A great deal of interest has surrounded the activities of monoclonal antibodies (mAbs), and mAb-drug, toxin and radionuclide conjugates for the treatment of human cancers. In the last few years, a number of new mAb-based reagents have been clinically approved (Rituxan, Herceptin, and Panorex), and several others are now in advanced clinical trials. Successful therapeutic treatment of solid tumors with drug conjugates of such macromolecules must overcome the barriers to penetration within tumor masses, antigen heterogeneity, conjugated drug potency, and efficient drug release from the mAbs inside tumor cells. An alternative strategy for drug delivery involves a two-step approach to cancer therapy in which mAbs are used to localize enzymes to tumor cell surface antigens. Once the conjugate binds to the cancer cells and clears from the systemic circulation, antitumor prodrugs are administered that are catalytically converted to active drugs by the targeted enzyme. The drugs thus released are capable of penetrating within the tumor mass and eliminating both cells that have and have not bound the mAb-enzyme conjugate. Significant therapeutic effects have been obtained using a broad range of enzymes along with prodrugs that are derived from both approved anticancer drugs and highly potent experimental agents. This review focuses on the activities of several mAb-enzyme/prodrug combinations, with an emphasis on those that have provided mechanistic insight, clinical activity, novel protein constructs, and the potential for reduced immunogenicity.
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Affiliation(s)
- P D Senter
- Seattle Genetics, 21823 30th Dr. SE, Bothell, WA 98021, USA.
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