MAPK3 and ovarian carcinoma: Overexpression of β-hCG promoted cell migration and invasion in ES-2 and SKOV3 ovarian cancer cell lines by transwell assays and wound healing in vitro and in a nude mouse model in vivo, while silencing β-hCG resulted in the opposite effect.[13] The effect of β-hCG was mediated by the activation of extracellular signal-regulated kinase 1/2 and matrix metalloprotease-2.[11] Overexpression of β-hCG also increased the expression of mesenchymal cell markers and decreased the expression of epithelial cell markers, thus improving EMT and metastasis of ovarian cancer.