On the other hand, over-expressions of HIF-1α, metallothionein and SLUG have been associated with high tumor-node-metastasis stage and lymph node metastasis in papillary thyroid carcinoma28; hence the evaluation of HIF-1α and MT may be useful in predicting the risk of lymph node metastasis and high tumor-node-metastasis stage and be associated with human cancer microenvironment. Here, HIF1A is linked to metastatic malignant neoplasm in the lymph nodes.