N-cadherin, a mesenchymal marker, attenuates Cx43 gap junction assembly in non-transformed cells by causing its internalization via the clathrin-independent pathway [48] and at the same time, its colocalization with Cx43, necessary for successful Cx43 membrane trafficking in the advanced stages of breast cancer to maintain cancer stem cell dormancy in bone metastatic niches [51]. This evidence concerns the gene GJA1 and breast cancer.