Effects of a topically applied bioadhesive berry gel on loss of heterozygosity indices in premalignant oral lesions. Clin Cancer Res 2008 Apr 15;14(8):2421-30
Date
04/17/2008Pubmed ID
18413833Pubmed Central ID
PMC3498466DOI
10.1158/1078-0432.CCR-07-4096Scopus ID
2-s2.0-42249107318 (requires institutional sign-in at Scopus site) 92 CitationsAbstract
PURPOSE: The aim of this study was to assess the effects of topical application of a 10% (w/w) freeze-dried black raspberry (FBR) gel on oral intraepithelial neoplasia (IEN) variables that included histologic diagnoses and loss of heterozygosity (LOH) indices. Microsatellite instability and/or LOH at tumor suppressor gene-associated chromosomal loci have been associated with a higher risk for oral IEN progression to oral squamous cell carcinoma. Previously, our laboratories have shown that FBRs are well tolerated and possess potent antioxidant, apoptotic, and differentiation-inducing properties.
EXPERIMENTAL DESIGN: Each participant with IEN served as their own internal control. Before treatment, all lesions were photographed, and lesional tissue was hemisected to obtain a pretreatment diagnosis and baseline biochemical and molecular variables. Gel dosing (0.5 g applied four times daily for 6 weeks) was initiated 1 week after the initial biopsy. Genomic DNA was isolated from laser-captured basilar and suprabasilar surface epithelial cells followed by PCR amplification using primer sets that targeted known and presumed tumor suppressor gene loci associated with INK4a/ARF, p53, and FHIT. Allelic imbalance was determined by sequence analysis using normal participant tissues to establish microsatellite marker peak patterns and allele sizes.
RESULTS: Confirming earlier phase I data, none of the 27 participants developed FBR gel-associated toxicities. Furthermore, our results show histologic regression in a subset of patients as well as statistically significant reduction in LOH at tumor suppressor gene-associated loci.
CONCLUSIONS: These preliminary data suggest that further evaluation of berry gels for oral IEN chemoprevention is warranted.
Author List
Shumway BS, Kresty LA, Larsen PE, Zwick JC, Lu B, Fields HW, Mumper RJ, Stoner GD, Mallery SRMESH terms used to index this publication - Major topics in bold
Administration, TopicalAdult
Aged
Female
Follow-Up Studies
Fruit
Gels
Genes, Tumor Suppressor
Humans
Loss of Heterozygosity
Male
Middle Aged
Mouth Neoplasms
Phytotherapy
Precancerous Conditions