SIX1 and neoplasm: Likewise, the occurrence of sine oculis homeobox homolog 1 (SIX1) overexpression in cervical tumor cells induces the activation of the TGF-β-SMAD pathway, which in turn mediates VEGF-C augmentation leading to the promoting effects on migration of tumor cells, tube formation of lymphatic endothelial cells (LEC) in vitro and lymphangiogenesis in vivo [49].