VTN and neoplasm: Studies found that hK6 was secreted to the extracellular matrix and involved in the degradation of matrix proteins including fibronectin, laminin, vitronectin, collagen and induced E-cadherin ectodomain shedding, reduced the cell-cell adhesion [11,12] and led to keratinocyte to promote tumor proliferation, migration, invasion and metastasis [13].