The possible biological mechanism is not clear, but in vitro studies also showed that lignan ENL in the presence of oestrogens suppressed the oestrogen-induced proliferation in MCF-7 breast cancer cell (Mousavi and Adlercreutz, 1992) and stimulated the synthesis of sex hormone-binding globulin in liver cells (Adlercreutz et al, 1992). This evidence concerns the gene SHBG and breast carcinoma.