IGF1 and breast cancer: For example, growth factors and growth factor receptors—such as Igf1, Tgfb3, Fgf1, Pgf, and Fgfr3—and oncogenes—such as Mecom, Met, Hes1, Myc, and Kit—were found to be upregulated and present in pathways including PI3K-Akt signaling, breast cancer signaling pathways regulating pluripotency of stem cells, PPAR signaling, etc. Igf1 is a growth factor important for postnatal mammary gland development.