Chemoprevention of oral cancer by lyophilized strawberries.
OBJECTIVE
Oral cancer represents approximately 2.5% of all cancers in the United States, with five- and 10-year survival rates of 62% and 51%. In the present study, lyophilized strawberries (LS) were evaluated for their potential to inhibit tumorigenesis in the hamster cheek pouch (HCP) model of oral cancer and for their ability to modify expression of several genes relevant to oral cancer development.


METHODS
HCPs were painted three times a week for six weeks with 0.2% 7,12-dimethylbenz(a)anthracene (DMBA). Hamsters were given 5% or 10% LS in their diet prior to, during, and after, or only after carcinogen treatment. Animals were sacrificed 12 weeks from the beginning of DMBA treatment and the number of total lesions and tumors was determined.


RESULTS
A significant difference (p<0.01-0.04) in the number of tumors was found between the LS-treated groups and the carcinogen controls. Histological examination of HCPs revealed a significant reduction in mild and severe dysplasia following 12 weeks of treatment with LS. Molecular analysis revealed that genes related to tumor development were modulated by LS.


CONCLUSIONS
These experiments support previous studies in HCP that demonstrated a chemopreventive activity by black raspberries and show, to our knowledge for the first time, that strawberries can inhibit tumor formation in an animal model of oral cancer.
College of Public Health, 400B-2 Cunz Hall, 1841 Neil Avenue, The Ohio State University, Columbus, OH, 43210, U.S.A. bcasto@cph.osu.edu.
Bruce C
BC
Casto
Thomas J
TJ
Knobloch
Rebecca L
RL
Galioto
Zhangsheng
Z
Yu
Brent T
BT
Accurso
Blake M
BM
Warner
D015127:9,10-Dimethyl-1,2-benzanthracene / Q000633:toxicity; D000818:Animals; D014408:Biomarkers, Tumor / Q000235:genetics*; D002273:Carcinogens / Q000633:toxicity; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D002471:Cell Transformation, Neoplastic / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006224:Cricetinae; D031985:Fragaria; D005612:Freeze Drying; D008297:Male; D008647:Mesocricetus; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
D014408:Biomarkers, Tumor; D002273:Carcinogens; D012333:RNA, Messenger; D015127:9,10-Dimethyl-1,2-benzanthracene
Chemoprevention; hamster cheek pouch; oral cancer; strawberries