| Abstract | CONTEXT: Currently, there is no effective treatment for iodine-resistant thyroid cancers. OBJECTIVE: As a new approach to treatment, the efficacy of replication-selective, human thyroglobulin (TG) enhancer and promoter-driven, adenovirus (AdhTGEP)-mediated oncolysis was investigated using two well-differentiated thyroid cancer cell lines, XTC (TG positive) and FTC-133 (TG negative), and other control tumor and nontumor cell lines (all TG negative). DESIGN: A cohort study design was used. SETTING: The study setting was laboratory bench-top experiments. SUBJECTS/PARTICIPANTS: In vitro TG-expressing and nonexpressing thyroid cell culture lines, nonthyroid tumor cell lines, as well as preclinical thyroid tumor-bearing mice were studied. INTERVENTION: Adenoviral infection of cell lines was determined by immunohistochemistry, selective replication by one-step growth assays, and cytotoxicity by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrozolium (MTS) assay. In vivo tumor growth inhibition was determined by a single intratumoral injection of 1 x 10(9) plaque-forming units AdhTGEP, AdLacZ (control virus), or PBS to 50- to 75-mm(3) tumors. XTC cells showed intense immunohistochemical staining, whereas FTC-133 and all other control cell lines showed minimal staining for viral infection with AdhTGEP. MAIN OUTCOME MEASURES: Cell survival and tumor growth inhibition after adenoviral infection were the main outcome measures. RESULTS: One-step growth assays showed at least a more than 60-fold titer of AdhTGEP in XTC than in FTC-133 cells. Cytotoxicity assays showed approximately 68% cell kill in XTC and minimal cell kill in FTC-133 and all other control cell lines at a multiplicity of infection of 250. There was significant in vivo growth inhibition of AdhTGEP-treated XTC tumors (67 +/- 49 mm(3)) compared with AdLacZ-treated XTC (228 +/- 45 mm(3); P < 0.01), PBS-treated XTC (372 +/- 70 mm(3); P < 0.001), or AdhTGEP-treated FTC-133 tumors (598 +/- 168 mm(3)). CONCLUSION: Replication-selective virus-mediated oncolysis is a potential therapy for recurrent, well-differentiated, TG-secreting thyroid cancer that is unresponsive to standard treatment. |
| Authors | Susan Kesmodel, Indira Prabakaran, Robert Canter, Chandrakala Menon, Kathy Molnar-Kimber, Douglas Fraker
(Affiliation: Division of Endocrine and Oncologic Surgery, HUP, 4 Silverstein Building, 3400 Spruce Street, Philadelphia, Pennsylvania 19104, USA.)
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| Journal | The Journal of clinical endocrinology and metabolism
(J Clin Endocrinol Metab)
Vol. 90
Issue 6
Pg. 3440-8
(Jun 2005)
ISSN: 0021-972X United States |
| PMID | 15797967
(Publication Type: Clinical Trial, Journal Article, Research Support, Non-U.S. Gov't)
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| Chemical References |
- DNA Primers
- Thyroglobulin
|
| Topics |
- Adenoviridae
(genetics, physiology)
- Base Sequence
- Cell Line
- Cell Survival
(drug effects)
- Cohort Studies
- DNA Primers
- Enhancer Elements, Genetic
- Gene Therapy
- Humans
- Promoter Regions, Genetic
- Thyroglobulin
(genetics)
- Thyroid Neoplasms
(pathology, therapy)
- Transfection
- Virus Replication
|
