CYP2E1 and breast cancer: To understand the role of CYP2E1 in these processes, the low invasive MCF7 and the highly invasive MDA-MB-231 as well as the MDA-MB-157 breast cancer cells were transiently transfected with CYP2E1 expressing constructs or vectors silencing the expression of this enzyme and cell migration was analysed employing the scratch wound assay.