A number of evidences support this discovery: i) anaplastic thyroid carcinoma cell lines expressing high levels of miR-146a display low D6/ACKR2 expression and blocking miR-146a in the same cells restored D6/ACKR2 expression; ii) reporter assays prove that D6/ACKR2 mRNA 3'UTR contains a specific sequence targeted by miR-146a in anaplastic thyroid carcinoma cell lines; iii) human specimens from normal and neoplastic thyroid tissues show an inverse correlation between miR-146a expression and D6/ACKR2 content. This evidence concerns the gene ACKR2 and thyroid gland undifferentiated (anaplastic) carcinoma.