Biomarkers Predict p53 Gene Therapy Efficacy in Recurrent Squamous Cell Carcinoma of the Head and Neck.
PURPOSE: Most recurrent squamous cell carcinomas of the head and neck have a dysfunctional p53 tumor suppressor pathway contributing to treatment resistance. We hypothesized that tumor p53 biomarkers may predict the efficacy of normal p53 delivered by gene therapy in these patients. EXPERIMENTAL DESIGN: Tumor p53 biomarkers were evaluated in 116 patients, including 29 treated with methotrexate in a phase III randomized controlled trial. Profiles favorable for p53 gene therapy efficacy were hypothesized to have either normal p53 gene sequences or low-level p53 protein expression, whereas unfavorable p53 inhibitor profiles were predicted to have high-level expression of mutated p53 that can inhibit normal p53 protein function. RESULTS: A statistically significant increase in tumor responses was observed for patients with favorable p53 efficacy profiles compared with those with unfavorable p53 inhibitor profiles [phase I/II trials: favorable (34 of 46, 74%) versus unfavorable (1 of 5, 20%), P = 0.0290; phase III trial: favorable (17 of 24, 71%) versus unfavorable (2 of 11, 18%), P = 0.0088]. In the phase III trial, there was statistically significant increased time to progression (TTP) and survival following p53 gene therapy in patients with favorable p53 profiles compared with unfavorable p53 inhibitor profiles (median TTP, 2.7 months versus 1.4 months, P = 0.0121; median survival, 7.2 months versus 2.7 months, P < 0.0001). In contrast, the biomarker profiles predictive of p53 gene therapy efficacy did not predict methotrexate response, TTP, or survival outcomes. CONCLUSIONS: These results indicate that tumor p53 biomarker profiles may predict p53 gene therapy efficacy in recurrent squamous cell carcinoma of the head and neck. (Clin Cancer Res 2009;15(24):7719-25).
Nemunaitis
John
J
Authors' Affiliations: Mary Crowley Cancer Research Centers, Dallas, Texas; The University of Texas M.D. Anderson Cancer Center; Introgen Therapeutics, Houston, Texas; St. Luke's Cancer Center, Bethlehem, Pennsylvania; WJB Dorn Veterans Affairs Medical Center, Columbia, South Carolina; Emory University School of Medicine, Atlanta, Georgia; University of Louisville, Louisville, Kentucky; Wayne State University, Detroit, Michigan; Hospital General Universitario Vall d' Hebron, Barcelona, Spain; Vanderbilt-Ingram Cancer Center, Nashville, Tennessee; University of Illinois, Chicago, Illinois; IARC, Lyon, France; and University of Miami Sylvester Cancer Center, Miami, Florida.
Clayman
Gary
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Agarwala
Sanjiv S
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Hrushesky
William
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Wells
James R
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Moore
Charles
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Hamm
John
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Yoo
George
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Baselga
Jose
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Murphy
Barbara A
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Menander
Kerstin A
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Licato
Laura L
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Chada
Sunil
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Gibbons
Robert D
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Olivier
Magali
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Hainaut
Pierre
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Roth
Jack A
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Sobol
Robert E
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Goodwin
W Jarrard
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