STAT3 and cancer: To gain insights into the molecular mechanisms underlying the pro-tumorigenic action of APLN, we screened nine important cancer pathways (BMP, MAPK (SRE), nuclear factor-кB (NF-кB), p38, p53, PI3K/Akt (FHRE), STAT3 (APRE), STAT5 (LHRE) and TGF-β by luciferase reporter assays.