A recent study that reported a role of DKK-2 in chemoresistance in breast cancer it is also noteworthy, with a description of the long non-coding RNA GAS5 as an endogenous “sponge” competing with miRNA-221-3p to regulate its target DKK-2, which in turn, inhibits the activation of Wnt pathway [40]. Here, DKK2 is linked to breast carcinoma.