SNAI1 and breast cancer: Another opioid agonist, nalbuphine, displaying affinity to MOR and KOR [57] when added to the human breast cancer cell cultures or administered to breast tumour-xenografted mice, resulting in decreased expression of vimentin, N-cadherin, and SNAIL1 but increased E-cadherin both at RNA and protein levels via repression of AKT-NFκB phosphorylation; therefore, this occurred through the inhibition of a powerful mitogenic and pro-migratory signalling pathway [58] (Table 2).