Inhibition by beta-carotene-rich algae Dunaliella of spontaneous mammary tumourigenesis in mice.

Effects of beta-carotene-rich algae Dunaliella on spontaneous mammary tumourigenesis were studied in SHN mice. In both breeder and virgin mice, mammary tumourigenesis was significantly inhibited in the experimental groups fed diets supplemented with spray dried powder of D. bardawil and oily solution of D. salina Teod. extract compared with the control. There was little difference between the experimental and the control groups in plasma prolactin level, endocrine organ weights and pattern of oestrous cycles. Moreover, mammary gland susceptibility to mammotrophic hormones was affected little by Dunaliella. These results suggest that the inhibition by Dunaliella of spontaneous mammary tumourigenesis of mice may not be through their modulation of endocrine systems.