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Advances on Delivery of Cytotoxic Enzymes as Anticancer Agents. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27123836. [PMID: 35744957 PMCID: PMC9230553 DOI: 10.3390/molecules27123836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 04/01/2022] [Accepted: 04/06/2022] [Indexed: 11/17/2022]
Abstract
Cancer is one of the most serious human diseases, causing millions of deaths worldwide annually, and, therefore, it is one of the most investigated research disciplines. Developing efficient anticancer tools includes studying the effects of different natural enzymes of plant and microbial origin on tumor cells. The development of various smart delivery systems based on enzyme drugs has been conducted for more than two decades. Some of these delivery systems have been developed to the point that they have reached clinical stages, and a few have even found application in selected cancer treatments. Various biological, chemical, and physical approaches have been utilized to enhance their efficiencies by improving their delivery and targeting. In this paper, we review advanced delivery systems for enzyme drugs for use in cancer therapy. Their structure-based functions, mechanisms of action, fused forms with other peptides in terms of targeting and penetration, and other main results from in vivo and clinical studies of these advanced delivery systems are highlighted.
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Saeb S, Assche JV, Loustau T, Rohr O, Wallet C, Schwartz C. Suicide gene therapy in cancer and HIV-1 infection: An alternative to conventional treatments. Biochem Pharmacol 2021; 197:114893. [PMID: 34968484 DOI: 10.1016/j.bcp.2021.114893] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 12/16/2022]
Abstract
Suicide Gene Therapy (SGT) aims to introduce a gene encoding either a toxin or an enzyme making the targeted cell more sensitive to chemotherapy. SGT represents an alternative approach to combat pathologies where conventional treatments fail such as pancreatic cancer or the high-grade glioblastoma which are still desperately lethal. We review the possibility to use SGT to treat these cancers which have shown promising results in vitro and in preclinical trials. However, SGT has so far failed in phase III clinical trials thus further improvements are awaited. We can now take advantages of the many advances made in SGT for treating cancer to combat other pathologies such as HIV-1 infection. In the review we also discuss the feasibility to add SGT to the therapeutic arsenal used to cure HIV-1-infected patients. Indeed, preliminary results suggest that both productive and latently infected cells are targeted by the SGT. In the last section, we address the limitations of this approach and how we might improve it.
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Affiliation(s)
- Sepideh Saeb
- Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; University of Strasbourg, Research Unit 7292, DHPI, IUT Louis Pasteur, Schiltigheim, France
| | - Jeanne Van Assche
- University of Strasbourg, Research Unit 7292, DHPI, IUT Louis Pasteur, Schiltigheim, France
| | - Thomas Loustau
- University of Strasbourg, Research Unit 7292, DHPI, IUT Louis Pasteur, Schiltigheim, France
| | - Olivier Rohr
- University of Strasbourg, Research Unit 7292, DHPI, IUT Louis Pasteur, Schiltigheim, France
| | - Clémentine Wallet
- University of Strasbourg, Research Unit 7292, DHPI, IUT Louis Pasteur, Schiltigheim, France
| | - Christian Schwartz
- University of Strasbourg, Research Unit 7292, DHPI, IUT Louis Pasteur, Schiltigheim, France.
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Shafiee F, Aucoin MG, Jahanian-Najafabadi A. Targeted Diphtheria Toxin-Based Therapy: A Review Article. Front Microbiol 2019; 10:2340. [PMID: 31681205 PMCID: PMC6813239 DOI: 10.3389/fmicb.2019.02340] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 09/25/2019] [Indexed: 12/26/2022] Open
Abstract
Cancer remains one of the leading causes of death worldwide. Conventional therapeutic strategies usually offer limited specificity, resulting in severe side effects and toxicity to normal tissues. Targeted cancer therapy, on the other hand, can improve the therapeutic potential of anti-cancer agents and decrease unwanted side effects. Targeted applications of cytolethal bacterial toxins have been found to be especially useful for the specific eradication of cancer cells. Targeting is either mediated by peptides or by protein-targeting moieties, such as antibodies, antibody fragments, cell-penetrating peptides (CPPs), growth factors, or cytokines. Together with a toxin domain, these molecules are more commonly referred to as immunotoxins. Targeting can also be achieved through gene delivery and cell-specific expression of a toxin. Of the available cytolethal toxins, diphtheria toxin (DT) is one of the most frequently used for these strategies. Of the many DT-based therapeutic strategies investigated to date, two immunotoxins, OntakTM and TagraxofuspTM, have gained FDA approval for clinical application. Despite some success with immunotoxins, suicide-gene therapy strategies, whereby controlled tumor-specific expression of DT is used for the eradication of malignant cells, are gaining prominence. The first part of this review focuses on DT-based immunotoxins, and it then discusses recent developments in tumor-specific expression of DT.
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Affiliation(s)
- Fatemeh Shafiee
- Department of Pharmaceutical Biotechnology, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Marc G Aucoin
- Department of Chemical Engineering, Faculty of Engineering, University of Waterloo, Waterloo, ON, Canada
| | - Ali Jahanian-Najafabadi
- Department of Pharmaceutical Biotechnology, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
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Eukaryotic expression vectors bearing genes encoding cytotoxic proteins for cancer gene therapy. Plasmid 2012; 68:69-85. [PMID: 22613563 DOI: 10.1016/j.plasmid.2012.05.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 02/11/2012] [Accepted: 05/09/2012] [Indexed: 01/03/2023]
Abstract
Cancer gene therapy is a promising direction for the treatment of cancer patients. A primary goal of all cancer therapies is to selectively target and kill tumour cells. Such therapies are administered via different approaches, including both viral and non-viral delivery; however, both methods have advantages and disadvantages. Transcriptional targeting enables genes encoding toxic proteins to be expressed directly in cancer cells. Numerous vectors have been created with the purpose of killing cancer cells, and some have successfully suppressed malignant tumours. Data concerning the function of vectors bearing genes that encode cytotoxic proteins under the control of different promoters, including tissue/tumour specific and constitutive promoters, is summarised here. This review focuses on vectors that bear genes encoding diphtheria toxin, Pseudomonas exotoxin A, caspases, gef, streptolysin, and melittin. Data describing the efficacy of such vectors have been summarised. Notably, there are vectors that killed cancer cell lines originating from the same type of cancer with differential efficiency. Thus, there is differential inhibition of cancer cell growth dependent on the cell line. In this review, the constructs employing genes whose expression induces cell death and the efficiency with which they suppress cancer cell growth will be summarised.
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Badr CE, Niers JM, Morse D, Koelen JA, Vandertop P, Noske D, Wurdinger T, Zalloua PA, Tannous BA. Suicidal gene therapy in an NF-κB-controlled tumor environment as monitored by a secreted blood reporter. Gene Ther 2010; 18:445-51. [PMID: 21150937 DOI: 10.1038/gt.2010.156] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The nuclear factor-κB (NF-κB) is known to be activated in many cancer types including lung, ovarian, astrocytomas, melanoma, prostate as well as glioblastoma, and has been shown to correlate with disease progression. We have cloned a novel NF-κB-based reporter system (five tandem repeats of NF-κB responsive genomic element (NF; 14 bp each)) to drive the expression cassette for both a fusion between the yeast cytosine deaminase and uracil phosphoribosyltransferase (CU) as a therapeutic gene and the secreted Gaussia luciferase (Gluc) as a blood reporter, separated by an internal ribosomal entry site (NF-CU-IGluc). We showed that malignant tumor cells have high expression of Gluc, which correlates to high activation of NF-κB. When NF-κB was further activated by tumor necrosis factor-α in these cells, we observed up to 10-fold increase in Gluc levels and therefore transgene expression in human glioma cells served to greatly enhance the sensitization of these cells to the prodrug, 5-fluorocytosine both in cultured cells and in vivo subcutaneous tumor xenograft model. This inducible system provides a tool to enhance the expression of imaging and therapeutic genes for cancer therapy.
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Affiliation(s)
- C E Badr
- Department of Neurology, Neuroscience Center, Massachusetts General Hospital, Boston, MA 02129, USA
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Toxin-based therapeutic approaches. Toxins (Basel) 2010; 2:2519-83. [PMID: 22069564 PMCID: PMC3153180 DOI: 10.3390/toxins2112519] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 10/25/2010] [Accepted: 10/26/2010] [Indexed: 01/08/2023] Open
Abstract
Protein toxins confer a defense against predation/grazing or a superior pathogenic competence upon the producing organism. Such toxins have been perfected through evolution in poisonous animals/plants and pathogenic bacteria. Over the past five decades, a lot of effort has been invested in studying their mechanism of action, the way they contribute to pathogenicity and in the development of antidotes that neutralize their action. In parallel, many research groups turned to explore the pharmaceutical potential of such toxins when they are used to efficiently impair essential cellular processes and/or damage the integrity of their target cells. The following review summarizes major advances in the field of toxin based therapeutics and offers a comprehensive description of the mode of action of each applied toxin.
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Modular Cre/lox system and genetic therapeutics for colorectal cancer. J Biomed Biotechnol 2009; 2009:358230. [PMID: 19809520 PMCID: PMC2754659 DOI: 10.1155/2009/358230] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Revised: 06/09/2009] [Accepted: 07/15/2009] [Indexed: 02/08/2023] Open
Abstract
The Cre/lox system is a powerful tool for targeting therapeutic effectors in a wide variety of human disorders. I review a Cre/lox Wnt-targeted system that has shown promise against Wnt-positive colorectal cancer cell lines. In addition to Wnt-specific targeting of cell death inducers, the modular nature of this gene therapy model system can be exploited by designing positive and negative feedback loops to either amplify or inhibit Wnt activity for experimental or therapeutic benefit. I discuss the structural components and performance parameters of the system, the implication of these findings with respect to cancer stem cells, as well as the general applicability of this system to any disorder characterized by differential gene expression. I also consider the issue of gene delivery as well as in vivo testing requirements necessary for the further characterization and development of this system.
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Glinka EM, Andryushchenko AS, Sapozhnikov AM, Zatsepina OV. Construction of the plasmid for expression of ETA-EGFP fusion protein under control of the cytomegalovirus promoter and its effects in HeLa cells. Plasmid 2009; 62:119-27. [PMID: 19527753 DOI: 10.1016/j.plasmid.2009.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 06/05/2009] [Accepted: 06/08/2009] [Indexed: 11/16/2022]
Abstract
Tumor-targeted vectors encoding toxic protein genes are promising tools for treating malignant tumors. We used the pEGFP-N1 vector to construct a novel plasmid (pCMV-ETA-EGFP) for eukaryotic expression of a truncated Pseudomonas aeruginosa exotoxin A (ETA) that is known to inhibit protein synthesis, and subsequently induce cell death, by inactivation of elongation factor-2. ETA was linked to the enhanced green fluorescent protein (EGFP) gene, and ETA-EGFP gene expression was driven by the cytomegalovirus (CMV) promoter. The time-lapse effects of pCMV-ETA-EGFP expression were examined in transiently transfected HeLa cells. HeLa cells transfected with pCMV-ETA-EGFP or cotransfected with pCMV-ETA-EGFP and small er, Cyrilliccapital IE, CyrillicGFP-N1 showed lower fluorescence intensity than cells transfected with pEGFP-N1 alone. Analysis of the number of dead cells further confirmed the highly toxic effect of the ETA-EGFP fusion protein on cells transfected with pCMV-ETA-EGFP or cotransfected with pCMV-ETA-EGFP and small er, Cyrilliccapital IE, CyrillicGFP-N1. ETA-EGFP fusion protein induced apoptotic cell death through the caspase-3 activation. By using the antibody against a marker nucleolar antigen A3 [Grigoryev, A.A., Bulycheva, T.I., Sheval, E.V., Kalinina, I.A., Zatsepina, O.V., 2008. Cytological indicators of the overall suppression of protein synthesis revealed by staining with new monoclonal antibody. Cell Tissue Biol. 2, 191-199], the distribution of which changes when HeLa cells are treated with known translation inhibitors, we obtained evidence to support the idea that protein synthesis is inhibited in transfected cells in situ. ETA-EGFP fusion protein was identified in lysates of transfected cells using anti-GFP-BL antibodies. Collectively, our results indicate that HeLa cells transfected with pCMV-ETA-EGFP synthesize the ETA-EGFP fusion protein that efficiently inhibits protein synthesis, leading to massive cell death by an apoptosis-mediated pathway with a participation of caspase-3. The constructed vector can be used in suicidal gene therapy of cancer and may also be useful for investigating the general effects of translational downregulation in human cancer cells. We also suggest a novel approach for detecting the activity of new vectors in transfected cells, which is based on the redistribution of nucleolar proteins in transfected cells.
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Affiliation(s)
- Elena M Glinka
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
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Bordonaro M, Lazarova DL, Sartorelli AC. Pharmacological and genetic modulation of Wnt-targeted Cre-Lox-mediated gene expression in colorectal cancer cells. Nucleic Acids Res 2004; 32:2660-74. [PMID: 15141037 PMCID: PMC419474 DOI: 10.1093/nar/gkh596] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Wnt-targeted gene therapy has been proposed as a treatment for human colorectal cancer (CRC). The Cre-Lox system consists of methodology for enhancing targeted expression from tissue-specific or cancer-specific promoters. We analyzed the efficiency of Wnt-specific promoters as drivers of the Cre-mediated activity of a luciferase reporter gene or cell death effector gene in CRC cell lines in the presence and absence of two modulators of Wnt activity, sodium butyrate and lithium chloride. Butyrate is present in the colonic lumen after digestion of fiber-rich foods, whereas the colonic lumen is readily accessible to lithium chloride. In both SW620 and HCT-116 CRC cells, a physiologically relevant concentration of butyrate upregulated reporter and effector activity and altered the Wnt-specific expression pattern. Lithium chloride markedly enhanced Cre-Lox-mediated Wnt-specific reporter expression only in APC wild-type CRC cells. Possibilities for genetic modulation of the proposed CRC therapy included Wnt-specific expression of a floxed Lef1-VP16 fusion that enhanced Wnt-specific cell death and of a floxed dominant-negative Tcf4 that specifically downregulated endogenous Wnt activity. These findings demonstrated that the Cre-Lox system, in combination with pharmacological and genetic modulators, represents effective methodology for enhancing Wnt-targeted gene therapy.
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Affiliation(s)
- Michael Bordonaro
- Department of Pharmacology and Developmental Therapeutics Section, Cancer Center, Yale University School of Medicine, New Haven, CT 06520, USA.
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Berry NB, Cho YM, Harrington MA, Williams SD, Foley J, Nephew KP. Transcriptional targeting in ovarian cancer cells using the human epididymis protein 4 promoter. Gynecol Oncol 2004; 92:896-904. [PMID: 14984958 DOI: 10.1016/j.ygyno.2003.12.024] [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] [Received: 08/06/2003] [Indexed: 12/01/2022]
Abstract
OBJECTIVE Limitations of current ovarian cancer gene therapies include lack of specificity and transduction of normal tissues. One strategy toward overcoming these limitations is to direct gene therapy specifically to ovarian cancer cells by using tissue- and tumor-specific promoters. The whey-acidic protein human epididymis protein 4 (HE4) is frequently overexpressed in ovarian cancer, suggesting that the HE4 promoter is highly transcriptionally active in the disease. The objective of this study was to isolate the HE4 promoter and examine its ability to selectively activate reporter gene expression in an ovarian cancer-specific manner. METHODS To investigate transcriptional targeting in ovarian cancer gene therapy, we isolated a region of the HE4 promoter from -530 to +122 (pHE4-652; relative to the ATG start site of HE4) and placed it upstream of a luciferase reporter gene plasmid to generate pHE4-652-luc. The activity of the pHE4-652-luc reporter construct was characterized in transient transfection assays in a panel of epithelial ovarian cancer cell lines (SKOV-3, SKOV-3x, CP70, HeyC2, A2780, A2780CP, OVCAR-3), non-ovarian tumor cell lines, and primary cultures of normal cells. The activity of two other candidate gene therapy promoters, human telomerase reverse transcriptase (hTERT) and OSP1, was also characterized in these cell lines. RESULTS The HE4 promoter was active in 5/7 ovarian cancer cell lines with the range of activity spanning 0.06- to 3-fold that observed for a positive control, cotransfected reporter construct (SV-40-luc). Minimal pHE4-652 promoter activity, defined as < or =5% of the activity detected with the SV-40-luc construct, was observed in the non-ovarian tumor cell lines and normal cells. The hTERT and the OSP1 promoters were active in the ovarian cancer lines. hTERT activity was highest in the CP70 cell line, and OSP1 activity was highest in the SKOV-3x cell line. Modest OSP1 and hTERT promoter activity was observed in normal cell lines and in selected non-ovarian cancer cell lines. CONCLUSION This is the first report using the pHE4-652 promoter to drive specific reporter gene expression in epithelial ovarian cancer cell lines, and we are continuing to develop this promoter for use in transcriptional targeting in ovarian cancer gene therapy.
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Affiliation(s)
- Nicholas B Berry
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA
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Ayesh B, Matouk I, Ohana P, Sughayer MA, Birman T, Ayesh S, Schneider T, de Groot N, Hochberg A. Inhibition of tumor growth by DT-A expressed under the control of IGF2 P3 and P4 promoter sequences. Mol Ther 2003; 7:535-41. [PMID: 12727117 DOI: 10.1016/s1525-0016(03)00056-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The human IGF2 P3 and P4 promoters are highly active in a variety of human cancers. We here present an approach for patient oriented therapy of TCC bladder carcinoma by driving the diphtheria toxin A-chain (DT-A) expression under the control of the IGF2 P3 and P4 promoter regulatory sequences. High levels of IGF2 mRNA expression from P3, P4 or both promoters were detected in 18 TCC samples (n = 29) by ISH or RT-PCR. Normal bladder samples (n = 4) showed no expression from either promoter. The activity and specificity of the IGF2 P3 and P4 regulatory sequences were established in human carcinoma cell lines by means of luciferase reporter gene assay. These sequences were used to design DT-A expressing, therapeutic vectors (P3-DT-A and P4-DT-A). The activity of both was determined in cell lines (in vitro) and the activity of P3-DT-A was determined in a heterotopic animal model (in vivo). The treated cell lines highly responded to the treatment in a dose-response manner, and the growth rate of the developed tumors in vivo was highly inhibited (70%) after intratumoraly injection with P3-DT-A compared to non-treated tumors (P < 0.0002) or tumors treated by luciferase gene expressing LucP3 vector (P < 0.002).
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Affiliation(s)
- B Ayesh
- Department of Biological Chemistry, Institute of Life Sciences, Hebrew University, Jerusalem 91904, Israel
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Peng W, Verbitsky A, Bao Y, Sawicki J. Regulated expression of diphtheria toxin in prostate cancer cells. Mol Ther 2002; 6:537-45. [PMID: 12377196 DOI: 10.1006/mthe.2002.0694] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Despite their known potential for effectively killing cells, the therapeutic use of plant and bacterial toxins for the treatment of cancer has been slow to enter the clinical setting. This has been due in large part to the lack of gene regulatory elements that control expression of highly toxic genes in a sufficiently tight manner, such that the toxins are only expressed in specific target cells. "Leaky" promoters result in unwanted and harmful cell death. In this study, we tested a novel gene therapy strategy aimed at expressing diphtheria toxin (DT-A) in androgen-independent prostate cancer cells that express the protein BCL2. This strategy relies on both transcriptional regulation and inducibly regulated DNA recombination mediated by the site-directed Flp recombinase to control expression of the toxin. Adenoviruses are used to introduce the genetic elements required for this approach into cultured cells and xenografts. Administration of 4-hydroxytamoxifen, resulting in recombination and expression of the toxin, effectively kills the cancer cells. Our results suggest that following androgen ablation therapy for the treatment of prostate cancer, use of a regulated recombination system to target expression of DT-A to androgen-independent cancer cells would be an effective way to arrest the development of recurrent tumors.
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Affiliation(s)
- Weidan Peng
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania 19096, USA.
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Bao R, Selvakumaran M, Hamilton TC. Targeted gene therapy of ovarian cancer using an ovarian-specific promoter. Gynecol Oncol 2002; 84:228-34. [PMID: 11812079 DOI: 10.1006/gyno.2001.6490] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES The "suicide" gene therapy of cancer using promoters such as cytomegalovirus could cause severe toxicity to normal tissues due to a lack of specificity of prodrug activation. Therefore, we investigated gene therapy of ovarian cancer using ovarian-specific promoter (OSP1) to limit the synthesis of the prodrug activating enzyme HSVtk to ovarian cancer cells. METHODS The HSVtk expressing plasmid pOSP1-HSVtk was created and transfected into an ovarian cancer cell line OVCAR3. The ganciclovir (GCV) sensitivity of the stable transfectants was evaluated with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Tissue specificity of this promoter was evaluated by comparing the sensitivity to GCV between ovarian and nonovarian cancer cell lines after they were transfected with pOSP1-HSVtk. One transfectant sensitive to GCV was implanted intraperitoneally to immunocompromised mice which were treated subsequently with GCV. Furthermore, this ovarian cancer survival model was used to evaluate the in vivo efficacy of cationic lipid mediated pOSP1-HSVtk gene delivery followed by GCV treatment. RESULTS Stable transfectants of OVCAR3 cells bearing OSP1-HSVtk became more sensitive to GCV treatment compared to the parental cell line and vector transfected OVCAR3 cell line. OSP1-HSVtk could specifically sensitize the OVCAR3 ovarian cancer cell line to GCV. SCID mice transplanted with the OVCAR3 transfectant and treated with GCV survived longer than the mice without GCV treatment (P = 0.032). In vivo gene delivery mediated by a cationic lipid (GL67) followed by GCV treatment yielded a longer survival in the OVCAR3 survival model (P = 0.016). CONCLUSIONS The OSP1 promoter can selectively direct suicide gene therapy of ovarian cancer and the in vivo efficacy is improved by using a cationic lipid GL67 as delivery vehicle as opposed to the direct injection of plasmid.
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Affiliation(s)
- Rudi Bao
- Ovarian Cancer Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA
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Casado E, Nettelbeck DM, Gomez-Navarro J, Hemminki A, Gonzalez Baron M, Siegal GP, Barnes MN, Alvarez RD, Curiel DT. Transcriptional targeting for ovarian cancer gene therapy. Gynecol Oncol 2001; 82:229-37. [PMID: 11531272 DOI: 10.1006/gyno.2001.6305] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ovarian carcinoma is a leading cause of cancer death in women. Though advances in conventional therapies have been achieved, long-term survival rates for most patients diagnosed with ovarian cancer are still low. Therefore, novel molecular therapeutic strategies such as gene therapy are being intensively pursued. Such approaches are based on the enormous progress that has been achieved in the elucidation of the molecular foundations of ovarian cancer. In this regard transcriptional control elements (promoters) of genes frequently upregulated or specifically expressed in tumors can be applied in a heterologous context to drive expression of therapeutic genes in targeted gene therapy strategies. This review discusses transcriptional targeting strategies in ovarian cancer gene therapy and gives an overview of tumor-specific promoters (TSPs) that have been applied for this purpose.
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Affiliation(s)
- E Casado
- Division of Human Gene Therapy, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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Abdul-Ghani R, Ohana P, Matouk I, Ayesh S, Ayesh B, Laster M, Bibi O, Giladi H, Molnar-Kimber K, Sughayer MA, de Groot N, Hochberg A. Use of transcriptional regulatory sequences of telomerase (hTER and hTERT) for selective killing of cancer cells. Mol Ther 2000; 2:539-44. [PMID: 11124054 DOI: 10.1006/mthe.2000.0196] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Telomerase (hTER and hTERT) plays a crucial role in cellular immortalization and carcinogenesis. Telomerase activity can be detected in about 85% of different malignant tumors, but is absent in most normal cells. In situ hybridization analysis showed that high levels of hTER and hTERT expression are present in bladder cancer, while no signal was detected in normal tissue. Therefore, in this work we propose to use hTER and hTERT transcriptional regulatory sequences to control the expression of a cytotoxic gene in bladder tumor cells, resulting in the selective destruction of this cell population. Expression vectors containing the diphtheria toxin A-chain (DT-A) gene were linked to hTER and hTERT transcriptional regulatory sequences, respectively. Inhibition of protein synthesis occurred in bladder and hepatocellular carcinoma cells transfected with the plasmids containing the DT-A gene under the control of the hTER or hTERT promoters in correlation with their activity. These studies support the feasibility of using hTER and hTERT transcriptional regulatory sequences for targeted patient-oriented gene therapy of human cancer.
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Affiliation(s)
- R Abdul-Ghani
- Department of Biological Chemistry, University of Pennsylvania Medical Center, Jerusalem, Pennsylvania 91904, Israel
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