Ad-mTERT-Δ19, a Conditional Replication-Competent Adenovirus Driven by the Human Telomerase Promoter, Selectively Replicates in and Elicits Cytopathic Effect in a Cancer Cell-Specific Manner

Autor: Chae-Ok Yun, Ha Youn Shin, Joohyuk Sohn, Jungho Kim, Joo Hang Kim, Hansaem Lee, Eun Hee Kim, Jai Myung Yang, Hoguen Kim
Rok vydání: 2003
Předmět:
Telomerase
Time Factors
Transcription
Genetic
cells
Tetrazolium Salts
medicine.disease_cause
Mice
Genes
Reporter
Coloring Agents
Promoter Regions
Genetic
Gene Transfer Techniques
Up-Regulation
Lac Operon
embryonic structures
Molecular Medicine
biological phenomena
cell phenomena
and immunity
Oncolytic adenovirus
Sp1 Transcription Factor
Blotting
Western
Genetic Vectors
Molecular Sequence Data
Mice
Nude
Antineoplastic Agents
Biology
Adenoviridae
Proto-Oncogene Proteins c-myc
Cell Line
Tumor
Genetics
medicine
Animals
Humans
Telomerase reverse transcriptase
neoplasms
Molecular Biology
Base Sequence
Models
Genetic
Neoplasms
Experimental
beta-Galactosidase
Telomere
Thiazoles
enzymes and coenzymes (carbohydrates)
Gene Expression Regulation
Viral replication
Cell culture
Cancer cell
Cancer research
Neoplasm Transplantation
HeLa Cells
Zdroj: Human Gene Therapy. 14:1415-1428
ISSN: 1557-7422
1043-0342
Popis: Human telomerase reverse transcriptase (hTERT), the catalytic subunit of telomerase, functions to stabilize telomere length during chromosomal replication. Previous studies have shown that hTERT promoter is highly active in most tumor and immortal cell lines but inactive in normal somatic cell types. The use of wild-type hTERT promoter, however, may be limited by its inability to direct high level and cancer cell-specific expression necessary for effective targeted gene therapy. To improve cancer cell specificity and the strength of the hTERT promoter, a modified hTERT, m-hTERT promoter was generated in which additional copies of c-Myc and Sp1 binding sites were incorporated adjacent to the promoter. As assessed using relative lacZ expression, hTERT and m-hTERT promoter activity was significantly upregulated in cancer cells but not in normal cells, and within these upregulated cancer cells, m-hTERT promoter strength was substantially higher than that of the wild-type hTERT. Next, to restrict viral replication to tumor cells, a conditional replication-competent adenoviruses, Ad-TERT-Delta19 and Ad-mTERT-delta19 were generated in which the E1A gene, which is essential for viral replication, was placed under the control of the hTERT and m-hTERT promoter, respectively. While the wild-type Ad-TERT-delta19 replicated in and induced cytopathic effect in cancer and in some normal cell lines, Ad-mTERT-delta19 enhanced viral replication and cytopathic effect only in cancer cells. Furthermore, the growth of established human cervical carcinoma in nude mice was significantly suppressed by intratumoral injection of Ad-mTERT-delta19. Taken together, present results strongly suggest that the use of the m-hTERT promoter is not only useful in the regulation of therapeutic gene expression but also that replication-competent oncolytic adenovirus under the control of the m-hTERT promoter may be a new promising tool for the treatment of human malignancies.
Databáze: OpenAIRE
Externí odkaz: