SIK2 and ovarian serous adenocarcinoma: An example of interaction between cancer and stromal cells in the metastatic niche can be observed in serous ovarian cancer: Ca2+ signals in ovarian cancer cells are induced by adipocytes, while Ca2+-dependent phosphorylation of the salt-inducible kinase 2 (SIK2) in ovarian cancer cells leads to the activation of fatty acid oxidation, AKT phosphorylation, and triggering of proliferative and pro-survival pathways [102].