MPO and cancer: In our former studies, toxic effects of ellipticine to several cancer cells were found to be dependent on expression of CYP1A1, 1B1, 3A4 and peroxidases LPO, COX and MPO in these cells (Bořek-Dohalská et al., 2004; Poljaková et al., 2007; 2009; Martínková et al., 2009).