Downregulation of miR‐138 is associated with overexpression of human telomerase reverse transcriptase protein in human anaplastic thyroid carcinoma cell lines

Alterations of several microRNA (miRNA) have been linked to cancer development and its biology. To search for unique miRNA that might play a role in the development of anaplastic thyroid carcinoma (ATC), we examined the expression of multiple miRNA and their functional effects on target genes in human thyroid carcinoma cell lines. We quantitatively evaluated the expression of multiple miRNA in 10 ATC and five papillary thyroid carcinoma (PTC) cell lines, as well as primary tumors from 11 thyroid carcinoma patients (three ATC and eight PTC), using the stem‐loop‐mediated reverse transcription real‐time polymerase chain reaction method. We also examined the target gene specificity of unique miRNA that showed differences in expression between ATC and PTC cell lines. One miRNA, miR‐138, was significantly downregulated in ATC cell lines in comparison with PTC (P