GNRH1 and breast cancer: LH-RH analogue AN-207 containing cytotoxic radical AN-201 also strongly inhibits DOX-resistant MX-1 human breast cancers in vivo (Kahan et al, 1999), indicating that 2-pyrrolino-DOX is non-cross-resistant with DOX, in analogy with similar highly potent derivatives of DOX such as Nemorubicin (Nagy and Schally, 2001).