Abstract | PURPOSE: EXPERIMENTAL DESIGN: We addressed the effect of p12 expression on tumor growth by using a well-established squamous cell carcinoma VII/SF floor of mouth xenograft mouse model. The effect of therapy on tumor growth was determined for: (a) no treatment, (b) PBS, (c) vehicle (1,2-dioleoyloxy-3-trimethylammonium propane: cholesterol liposomes / 5% dextrose), (d) empty vector controls, and (e) p12-encoding vector experimental groups. RESULTS: p12 gene therapy significantly induced antitumor effects as compared with controls, including (a) size and weight of p12-treated tumors decreased by 51% to 72% compared with all controls (P < 0.02), (b) tumor growth rate post- therapy was inhibited by 55% to 64% compared with empty vector controls (P < 0.0001), and (c) p12 expression was higher in p12-treated than controls (P < 0.002) by two-tailed t test analyses. Mechanistically, p12 treatment affected cell turnover kinetics as assessed by apoptotic and cell proliferation indices. p12 therapy significantly increased terminal nucleotidyl transferase-mediated nick end labeling (P < 0.05) and morphology-based apoptotic indices (P < 0.05) as well as significantly decreased Ki-67 cell proliferation indices (P < 0.001) compared with controls, resulting in a net cell turnover reduction in p12-treated tumors. CONCLUSIONS: We show that this novel therapeutic modality can significantly induce antitumor responses in vivo. These results support a role for p12 as a novel tumor growth suppressor gene therapy and suggest that optimization and/or combination with current therapies may hold considerable promise in preparation for clinical trials.
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Authors | Marxa L Figueiredo, Yong Kim, Maie A R St John, David T W Wong |
Journal | Clinical cancer research : an official journal of the American Association for Cancer Research
(Clin Cancer Res)
Vol. 11
Issue 10
Pg. 3939-48
(May 15 2005)
ISSN: 1078-0432 [Print] United States |
PMID | 15897596
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- CDK2AP1 protein, human
- Tumor Suppressor Proteins
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Topics |
- Animals
- Apoptosis
- Carcinoma, Squamous Cell
(genetics, pathology, veterinary)
- Cell Proliferation
- Disease Models, Animal
- Disease Progression
- Genetic Therapy
- Head and Neck Neoplasms
(genetics, pathology, veterinary)
- Mice
- Transplantation, Heterologous
- Tumor Suppressor Proteins
(genetics, pharmacology)
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