Conversely, in vitro cortisol supplementation significantly increased the expression of GHR and IGF1R in epithelial cells. Other authors have reported that GH and IGF-1 can modulate the survival of epithelial cells (Capuco et al., 2001; Flint et al., 2005; Rosenfeld and Hwa, 2009), and the increase in expression of GHR and IGF1R observed in vitro in the study can explain why GH and IGF-1 were previously associated with cell proliferation (Flint et al., 2008; Murney et al., 2015). As cortisol did not change the expression of IGF1, IGFBP3, or IGFBP5, our results demonstrated the direct effect of cortisol on the expression of GHR and IGF1R in mammary tissue, further suggesting that large amounts of cortisol can improve the actions of GH and IGF-1 in mammary cells, as reported in other studies that worked with large amounts by long-term exposure to glucocorticoid and other cells (Savage et al., 2011; Vakili and Cattini, 2012). In fact, the overexpression of GHR and IGF1R genes protects different cells against apoptosis