Figure 1: Signaling pathways and positive or negative effects of different hormones on the growth, differentiation, proliferation and establishment of parasitic cells. Some hormone signals are involved in the expression of transcription factors in the cell nucleus (genomic effects). These factors regulate the gene expression or the second messenger expression (no genomic effects), which results in the activation and/or inhibition of signaling cascades. DHEA: dehydroepiandrosterone; P4: Progesterone; EGF: murine epidermal growth factor; E2: 17-β-Estradiol.