PROX1 and thyroid cancer: Moreover, in order to determine whether the PROX1 gene is involved in thyroid cancer progression, we determined the effect of PROX1 silencing and overexpression on the cellular processes associated with the metastatic potential of tumor cells, such as proliferation, migration, invasion, apoptosis and anchorage-independent growth, in the FTC-133 human follicular thyroid carcinoma cell line.