GNRH1 and cancer: As can be seen in Figure 4B, crizotinib* (IC50 = 2.6 μM), MJ55* (IC50 = 2.6 μM), and [d-Lys6(MJ55*)]–GnRH-I (IC50 = 3.0 μM) were less effective on healthy fibroblast cells than on EBC-1 cancer cells.