Multiple berry types prevent N-nitrosomethylbenzylamine-induced esophageal cancer in rats.
OBJECTIVE
The present study compared the ability of different berry types to prevent chemically-induced tumorigenesis in the rat esophagus. We also determined if berries influence the levels of inflammatory cytokines in the serum of carcinogen-treated rats.


METHODS
Rats were treated with the carcinogen N-nitrosomethylbenzylamine (NMBA) for 5 weeks, then placed on diets containing 5% of either black or red raspberries, strawberries, blueberries, noni, açaí or wolfberry until the end of the study. The effects of the berries on tumor incidence, multiplicity and size were determined, as well as their effects on the levels of selected inflammatory cytokines in serum.


RESULTS
All berry types were about equally effective in inhibiting NMBA-induced tumorigenesis in the rat esophagus. They also reduced the levels of the serum cytokines, interleukin 5 (IL-5) and GRO/KC, the rat homologue for human interleukin-8 (IL-8), and this was associated with increased serum antioxidant capacity.


CONCLUSIONS
Seven berry types were about equally capable of inhibiting tumor progression in the rat esophagus in spite of known differences in levels of anthocyanins and ellagitannins. Serum levels of IL-5 and GRO/KC (IL-8) may be predictive of the inhibitory effect of chemopreventive agents on rat esophageal carcinogenesis.
Department of Internal Medicine and Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA. gary.stoner@osumc.edu
Gary D
GD
Stoner
Li-Shu
LS
Wang
Claire
C
Seguin
Claudio
C
Rocha
Kristen
K
Stoner
Steven
S
Chiu
A Douglas
AD
Kinghorn
D000818:Animals; D016588:Anticarcinogenic Agents / Q000627:therapeutic use*; D000975:Antioxidants / Q000378:metabolism; D001835:Body Weight; D018890:Chemoprevention; D004128:Dimethylnitrosamine / Q000031:analogs & derivatives; D004435:Eating; D004938:Esophageal Neoplasms / Q000139:chemically induced / Q000178:diet therapy* / Q000517:prevention & control*; D005638:Fruit / Q000378:metabolism; D006801:Humans; D015848:Interleukin-5 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood; D008297:Male; D008517:Phytotherapy; D051381:Rats; D017207:Rats, Sprague-Dawley
D016588:Anticarcinogenic Agents; D000975:Antioxidants; D015848:Interleukin-5; D016209:Interleukin-8; C014707:nitrosobenzylmethylamine; D004128:Dimethylnitrosamine