HMGA1 and thyroid gland undifferentiated (anaplastic) carcinoma: Indeed, papillary thyroid carcinomas (PTC), which are fine differentiated and weakly aggressive, express low levels of HMGA1P6, HMGA1P7 and HMGA1. On the contrary, anaplastic thyroid carcinomas (ATC), which are one of the most malignant human cancers, express very high HMGA1Ps levels that, moreover, correlated with HMGA1 protein levels [100].