RT Journal Article SR Electronic T1 Periostin Plays a Key Role in Radioresistance of Head and Neck Cancer Cells Via Epithelial-to-Mesenchymal Transition JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 2627 OP 2635 DO 10.21873/anticanres.14233 VO 40 IS 5 A1 JUNG JE PARK A1 YOUNG-SOOL HAH A1 SOMI RYU A1 SO YOUNG CHEON A1 HEE YOUNG CHO A1 JIN PYEONG KIM A1 SEONG JUN WON A1 JONG SIL LEE A1 JEONG SEOK HWA A1 JI HYUN SEO A1 HYO WON CHANG A1 SANG YOON KIM YR 2020 UL http://ar.iiarjournals.org/content/40/5/2627.abstract AB Background/Aim: Head and neck squamous cell carcinoma (HNSCC) is an aggressive head and neck malignancy. The aim of this study was to elucidate the role of periostin (POSTN) in the epithelial-to-mesenchymal transition (EMT) process mediating the acquisition of radioresistance in HNSCC. Materials and Methods: The expression levels of EMT hallmark genes including POSTN and Erk/Akt signaling pathways were compared between radiosensitive and radioresistant HNSCC cells. Results: POSTN mRNA expression was higher in radioresistant HNSCC cells, and silencing POSTN significantly impaired their invasiveness under the effect of EMT process represented by up-regulation of mesenchymal markers and down-regulation of an epithelial marker. Expression levels of Erk and Akt were higher in radioresistant cells. Conclusion: POSTN in association with the Erk and Akt signaling pathways was up-regulated during the EMT process, leading to the conversion of radiosensitive to radioresistant HNSCC cells. POSTN may be a key marker for predicting the radioresistance and therapeutic target of HNSCC.