Food Factors for Cancer Prevention

Abstract

The prophylactic effect of an oral Lactobacillus casei preparation (Biolactis powder: BLP) on the recurrence of superficial bladder cancer and the mechanisms involved are reviewed. The immunopotentiating effect of BLP was assessed in tumor-bearing BALB/c mice and its inhibitory effect on N-butyl-N- (4-hydroxybutyl)nitrosamine-induced bladder carcinogenesis was assessed in male Wistar rats and C3H/He mice. The safety and efficacy of BLP in preventing bladder cancer recurrence after transurethral resection were assessed in two clinical trials. In BALB/c mice, BLP reduced the growth of secondary tumors and augmented proliferation and cytokine production by splenocytes. It also significantly inhib- ited bladder tumor formation in rats and mice, and the tumors developing in BLP-treated animals showed a lower grade of malignancy. In a randomized clinical trial, BLP significantly prolonged the recurrence-free interval by 1.8-fold compared to that in the controls. In a double-blind trial, BLP significantly delayed recurrence in patients with multiple primary or single recurrent tumors and downgraded the recurrent lesions. BLP appears to modify the intestinal flora and reduce the produc- tion of chemical carcinogens, resulting in significant anti tumor and prophylactic activity in animals and humans.