This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Li, D. Articles by O’Malley, B. W. Search for Related Content PubMed PubMed Citation Articles by Li, D. Articles by O’Malley, B. W., Jr.

The Role of Adenovirus-mediated Retinoblastoma 94 in the Treatment of Head and Neck Cancer

Department of Otolaryngology-Head and Neck Surgery [D. L., K. V. D., S. Y., G. S., S. L., M. G., Y. X., B. W. O.] and Greenebaum Cancer Center [D. L., B. W. O.], University of Maryland School of Medicine, Baltimore, Maryland 21201, and Titan Pharmaceuticals, San Francisco, California 94080 [S. S.]

A truncated retinoblastoma (RB) protein of 94 kDa (RB94), lacking theNH₂ -terminal 112 amino acid residues of the full-length RB, has been found to have great efficacy in tumor suppression. This study investigated the role of adenovirus-mediated RB94 (Ad-RB94) gene therapy for human head and neck squamous cell carcinoma (HNSCC) and explored the cellular and molecular mechanism of tumor inhibition after Ad-RB94 gene transfer. Randomized controlled studies in vitro and in vivo were performed to assess antitumor responses of Ad-RB94 gene transfer against human HNSCC. Human HNSCC cell lines, JHU006 and JHU012, were used in this study. Tumors originated from the HNSCC cell lines were propagated as xenografts in nude mice. Ad-RB94 gene transfer was performed both in vitro and in vivo with replication-defective virus (DL312) and no treatment as controls. Transgene expression, cell viability, and tumor growth were evaluated in transfected cells and tumor implants. To determine the mechanism behind the observed antitumor action, cell cycle analysis was performed, and telomerase activity was examined. Tumors were evaluated for RB94-induced apoptosis. Transgene expression of RB94 was detected by Western blot analysis, real-time quantification reverse transcription-PCR, and immunohistochemistry. RB94 expression led to flattening of cell growth curves and caused tumor regression. Animals treated with Ad-RB94 were seen to have a significant reduction in tumor size when compared with DL312 (P = 0.02, both cell lines) and to no treatment groups (P = 0.01, both cell lines). Cell cycle arrest in the G₂-M phase and increased levels of apoptosis occurred in tumor cells treated with Ad-RB94. In addition, telomerase activity decreased significantly and specifically after Ad-RB94 treatment. This study demonstrates that Ad-RB94 gene transfer effectively inhibits HNSCC tumor cell growth in vitro and in vivo. The unique property of Ad-RB94 gene transfer to arrest HNSCC tumor cells in the G₂-M phase of the cell cycle makes it a good candidate for adjuvant therapy with radiation or chemotherapy, as tumor cells are most sensitive to radiation or cytotoxic drug in this cell cycle phase.

This article has been cited by other articles:

				K. Araki, S. M. Ahmad, G. Li, D. A. Bray Jr, K. Saito, D. Wang, U. Wirtz, S. Sreedharan, B. W. O'Malley Jr, and D. Li Retinoblastoma RB94 Enhances Radiation Treatment of Head and Neck Squamous Cell Carcinoma Clin. Cancer Res., June 1, 2008; 14(11): 3514 - 3519. [Abstract] [Full Text] [PDF]

				M. L. Figueiredo, Y. Kim, M. A.R. St. John, and D. T.W. Wong p12CDK2-AP1 Gene Therapy Strategy Inhibits Tumor Growth in an In vivo Mouse Model of Head and Neck Cancer Clin. Cancer Res., May 15, 2005; 11(10): 3939 - 3948. [Abstract] [Full Text] [PDF]

				J. M. Roig, M. A. Molina, A. Cascante, J. Calbo, N. Carbo, U. Wirtz, S. Sreedharan, C. Fillat, and A. Mazo Adenovirus-Mediated Retinoblastoma 94 Gene Transfer Induces Human Pancreatic Tumor Regression in a Mouse Xenograft Model Clin. Cancer Res., February 15, 2004; 10(4): 1454 - 1462. [Abstract] [Full Text] [PDF]

				X. Zhang, A. S. Multani, J.-H. Zhou, J. W. Shay, D. McConkey, L. Dong, C.-S. Kim, C. J. Rosser, S. Pathak, and W. F. Benedict Adenoviral-mediated Retinoblastoma 94 Produces Rapid Telomere Erosion, Chromosomal Crisis, and Caspase-dependent Apoptosis in Bladder Cancer and Immortalized Human Urothelial Cells but not in Normal Urothelial Cells Cancer Res., February 15, 2003; 63(4): 760 - 765. [Abstract] [Full Text] [PDF]