Inhibition of azoxymethane-induced colon cancer by orange juice

Previous research has shown that hesperidin, a flavanone glycoside in orang e juice, inhibits colon carcinogenesis and that feeding double-strength ora nge juice delays the onset of chemically induced mammary cancer in rats. Th is study determined whether feeding single-strength. pasteurized orange jui ce would inhibit azoxymethane (AOM)-induced colon cancer in male Fischer 34 4 rats. Colon cancer was initiated by injecting AOM (15 mg/kg body wt) at 2 2 and 29 days of age. One week after the second AOM injection, orange juice replaced drinking water for the experimental group (n = 30). The rats were killed 28 weeks later, and tumors were removed for histological analysis. Feeding orange juice reduced tumor incidence by 22% (p < 0.05). Tumor reduc tion was associated with a decreased labeling index and proliferation zone in the colonic mucosa. Hesperidin, other flavonoids, limonin 17-beta-D-gluc opyranoside, and other limonoid glucosides are potential chemopreventive ag ents in orange juice that could account for the decreased colon tumorigenes is associated with feeding orange juice.