TY - JOUR AB - Anaplastic thyroid cancer (ATC) remains a cancer with one of the worst prognoses, despite novel targeted therapies. The median survival rate has not improved for decades. Epithelial‑to‑mesenchymal transition (EMT) is a crucial step in physiological processes and in cancer progression, but the underlying mechanisms are not yet fully understood. The current study examined the role of microRNA (miR)‑200b in mesenchymal‑to‑epithelial transition in ATC. Total RNA and miR isolation were performed from ATC cell lines transfected with a miR‑200b mimic. After miR‑200b mimic transfection, expression levels of E‑cadherin, vimentin and zinc finger E‑box binding homeobox 1 (ZEB1) were confirmed by reverse transcription‑quantitative PCR and western blotting. Additionally, cell migration was evaluated using miR‑200b mimic and scrambled negative control‑transfected cells. A total of 14 human ATC and 15 non‑cancerous human thyroid tissues were immunohistochemically stained and scored as controls for E‑cadherin, vimentin and ZEB1. In ATC tissues and cell lines, the mesenchymal marker ZEB1 was significantly upregulated and the epithelial marker E‑cadherin was significantly downregulated. Additionally, the mesenchymal marker vimentin was significantly upregulated in ATC tissues and in one ATC cell line. MiR‑200b mimic transfection significantly increased vimentin and ZEB1 expression, but E‑cadherin expression remained below the measurement sensitivity. Furthermore, miR‑200b overexpression decreased cell migration. The current study suggested that miR‑200b may regulate the expression levels of mesenchymal markers such as vimentin and ZEB1 in ATC and may promote mesenchymal‑to‑epithelial transition. AD - Department of Otolaryngology‑Head and Neck Surgery, Wakayama Medical University, Wakayama, Wakayama 641‑8509, Japan Department of Pathology, Wakayama Medical University, Wakayama, Wakayama 641‑8509, Japan Noguchi Thyroid Clinic and Hospital Foundation, Beppu, Oita 874‑0902, Japan AU - Tamagawa,Shunji AU - Enomoto,Keisuke AU - Gunduz,Esra AU - Gunduz,Mehmet AU - Sato,Fuyuki AU - Uchino,Shinya AU - Muragaki,Yasuteru AU - Hotomi,Muneki DA - 2020/10/01 DO - 10.3892/ol.2020.11864 IS - 4 JO - Oncol Lett KW - anaplastic thyroid carcinoma epithelial‑to‑mesenchymal transition microRNA 200b vimentin zinc finger E‑box binding homeobox 1 PY - 2020 SN - 1792-1074 1792-1082 SP - 3 ST - MicroRNA 200b promotes mesenchymal‑to‑epithelial transition in anaplastic thyroid carcinoma T2 - Oncology Letters TI - MicroRNA 200b promotes mesenchymal‑to‑epithelial transition in anaplastic thyroid carcinoma UR - https://doi.org/10.3892/ol.2020.11864 VL - 20 ER -