The influence of soybean extract on the expression level of selected drug transporters, transcription factors and cytochrome P450 genes encoding phase I drug-metabolizing enzymes.

Objective: Soybean phytoestrogens, such as genistein and daidzein, reduce climacteric symptoms and the risk of certain chronic diseases such as cancer and cardiovascular diseases. Despite their widespread use in functional foods and dietary supplements, there is very little data available on their safety and herb-drug interactions, especially with antineoplastic agents. Hence, the aim of our study was to assess the effects of soybean extracts on the expression level of CYP genes and their transcriptional factors.