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 PARK, JUNG JE A1 HAH, YOUNG-SOOL A1 RYU, SOMI A1 CHEON, SO YOUNG A1 CHO, HEE YOUNG A1 KIM, JIN PYEONG A1 WON, SEONG JUN A1 LEE, JONG SIL A1 HWA, JEONG SEOK A1 SEO, JI HYUN A1 CHANG, HYO WON A1 KIM, SANG YOON 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.