In this regard, is thought that over-expression of HER2 in human cancer cells due to amplification enhances the preferential binding of the low-affinity arm of ligands to HER2 resulting in increased intracellular signaling [44] that could ultimately lead to the control of ZO-1 and potential regulation of ZO-1 mediated cell-cell interactions. The gene discussed is TJP1; the disease is cancer.