HMGA2 and cancer: HMGA2 or High Mobility Group AT-Hook 2 is a nuclear non histone chromatin-associated protein that acts as a transcription factor regulating the expression of various genes; this gene is not expressed in normal tissues, but is expressed in malignant tumors and has been proposed as a malignancy marker in thyroid [33, 40–44] and other types of cancers [45, 46].