Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene Therapy
Telomerase expression represents a good target for cancer gene therapy. The promoters of the core telomerase catalytic [human telomerase reverse transcriptase (hTERT)] and RNA [human telomerase RNA (hTR)] subunits show selective activity in cancer cells but not in normal cells. This property can be...
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| Format: | Article |
| Language: | English |
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Elsevier
2005-11-01
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| Series: | Neoplasia: An International Journal for Oncology Research |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1476558605800375 |
| _version_ | 1819202826003283968 |
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| author | Alan E. Bilsland Aileen Fletcher-Monaghan W. Nicol Keith |
| author_facet | Alan E. Bilsland Aileen Fletcher-Monaghan W. Nicol Keith |
| author_sort | Alan E. Bilsland |
| collection | DOAJ |
| description | Telomerase expression represents a good target for cancer gene therapy. The promoters of the core telomerase catalytic [human telomerase reverse transcriptase (hTERT)] and RNA [human telomerase RNA (hTR)] subunits show selective activity in cancer cells but not in normal cells. This property can be harnessed to express therapeutic transgenes in a wide range of cancer cells. Unfortunately, weak hTR and hTERT promoter activities in some cancer cells could limit the target cell range. Therefore, strategies to enhance telomerasespecific gene therapy are of interest. We constructed a Cre/Lox reporter switch coupling telomerase promoter specificity with Cytomegalovirus (CMV) promoter activity, which is generally considered to be constitutively high. In this approach, a telomerase-specific vector expressing Cre recombinase directs excisive recombination on a second vector, removing a transcriptional blockade to CMV-dependent luciferase expression. We tested switch activation in cell lines over a wide range of telomerase promoter activities. However, Cre/Lox-dependent luciferase expression was not enhanced relative to expression using hTR or hTERT promoters directly. Cell-specific differences between telomerase and CMV promoter activities and incomplete sigmoid switch activation were limiting factors. Notably, CMV activity was not always significantly stronger than telomerase promoter activity. Our conclusions provide a general basis for a more rational design of novel recombinase switches in gene therapy. |
| first_indexed | 2024-12-23T04:10:11Z |
| format | Article |
| id | doaj.art-c08d137303514853a723ca27f3e65ce6 |
| institution | Directory Open Access Journal |
| issn | 1476-5586 1522-8002 |
| language | English |
| last_indexed | 2024-12-23T04:10:11Z |
| publishDate | 2005-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Neoplasia: An International Journal for Oncology Research |
| spelling | doaj.art-c08d137303514853a723ca27f3e65ce62022-12-21T18:00:31ZengElsevierNeoplasia: An International Journal for Oncology Research1476-55861522-80022005-11-017111020102910.1593/neo.05385Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene TherapyAlan E. BilslandAileen Fletcher-MonaghanW. Nicol KeithTelomerase expression represents a good target for cancer gene therapy. The promoters of the core telomerase catalytic [human telomerase reverse transcriptase (hTERT)] and RNA [human telomerase RNA (hTR)] subunits show selective activity in cancer cells but not in normal cells. This property can be harnessed to express therapeutic transgenes in a wide range of cancer cells. Unfortunately, weak hTR and hTERT promoter activities in some cancer cells could limit the target cell range. Therefore, strategies to enhance telomerasespecific gene therapy are of interest. We constructed a Cre/Lox reporter switch coupling telomerase promoter specificity with Cytomegalovirus (CMV) promoter activity, which is generally considered to be constitutively high. In this approach, a telomerase-specific vector expressing Cre recombinase directs excisive recombination on a second vector, removing a transcriptional blockade to CMV-dependent luciferase expression. We tested switch activation in cell lines over a wide range of telomerase promoter activities. However, Cre/Lox-dependent luciferase expression was not enhanced relative to expression using hTR or hTERT promoters directly. Cell-specific differences between telomerase and CMV promoter activities and incomplete sigmoid switch activation were limiting factors. Notably, CMV activity was not always significantly stronger than telomerase promoter activity. Our conclusions provide a general basis for a more rational design of novel recombinase switches in gene therapy.http://www.sciencedirect.com/science/article/pii/S1476558605800375TelomerasehTRhTERTCre recombinasegene therapy |
| spellingShingle | Alan E. Bilsland Aileen Fletcher-Monaghan W. Nicol Keith Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene Therapy Neoplasia: An International Journal for Oncology Research Telomerase hTR hTERT Cre recombinase gene therapy |
| title | Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene Therapy |
| title_full | Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene Therapy |
| title_fullStr | Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene Therapy |
| title_full_unstemmed | Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene Therapy |
| title_short | Properties of a Telomerase-Specific Cre/Lox Switch for Transcriptionally Targeted Cancer Gene Therapy |
| title_sort | properties of a telomerase specific cre lox switch for transcriptionally targeted cancer gene therapy |
| topic | Telomerase hTR hTERT Cre recombinase gene therapy |
| url | http://www.sciencedirect.com/science/article/pii/S1476558605800375 |
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