GREB1 and breast cancer: Among these, two are interesting in this context: (1) AKAP1 encodes an A-kinase anchor proteins that anchors PKA to mitochondria; correct localization of PKA is required for oocyte maturation (Newhall et al., 2006; Nishimura et al., 2013) and (2) GREB1 encodes an early response gene in the estrogen-regulated pathway and is involved in hormone-dependent breast cancer cell growth (Rae et al., 2005).