title: HMGB1 attenuates TGF-β-induced epithelial-mesenchymal transition of FaDu hypopharyngeal carcinoma cells through regulation of RAGE expression.
abstract: Abnormal expression of high-mobility group box-1 (HMGB1) protein occurs in many tumors and is closely associated with tumor invasion and metastasis. However, a role for HMGB1 in epithelial-mesenchymal transition (EMT) in hypopharyngeal carcinoma has not been previously reported. We cultured cells of the hypopharyngeal carcinoma cell line FaDu in vitro and then treated them with 5 ng/ml TGF-β1 for 48 h to induce EMT. Vimentin, Snail, and HMGB1 expression patterns were then detected using immunofluorescence staining; HMGB1 mRNA and protein expression were verified by RT-PCR and western blot analyses. HMGB1 was then silenced in FaDu cells using RNAi, followed by detection of Vimentin, Snail, and HMGB1 expressions by immunofluorescence staining. The mRNA expression levels of Vimentin, Snail, HMGB1, and E-cadherin were verified by RT-PCR, while protein expression of HMGB1 and receptor for advanced glycation end products (RAGE) were detected by western blot analysis. The biological behavior of FaDu cells was observed before and after HMGB1 silencing using wound healing and cell invasion assays. Following culture with 5 ng/ml TGF-β1 for 48 h, the morphology of FaDu cells changed from a regular cobblestone-like appearance into a spindle-like shape. Expression levels of Vimentin, Snail, and HMGB1 were upregulated at both mRNA and protein levels as determined by RT-PCR, immunofluorescence, and western blotting. After HMGB1 silencing, mRNA expression levels of the epithelial cell marker E-cadherin were upregulated. Meanwhile, expression levels of the mesenchymal markers Vimentin and Snail were decreased. Western blotting revealed that HMGB1 and RAGE were downregulated. RNAi-mediated inhibition of HMGB1 expression decreased the capacities of FaDu cells for invasion and metastasis as determined by wound healing and cell invasion assays. HMGB1 is essential for maintaining the interstitial cell phenotype in TGF-β1-induced EMT of FaDu cells, and silencing HMGB1 greatly inhibits the invasive and metastatic ability of these cells.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, First Hospital of Jilin University, Changchun, 130021, China.|Department of Medical Genetics, College of Basic Medical Sciences, Jilin University, Changchun, 130021, China.
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, First Hospital of Jilin University, Changchun, 130021, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Medical Genetics, College of Basic Medical Sciences, Jilin University, Changchun, 130021, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, First Hospital of Jilin University, Changchun, 130021, China.
authors.forename: Haonan
authors.initials: H
authors.lastname: Li
authors.affiliation: Center for Stem Cell and Translational Medicine, School of Life Sciences of Anhui University, Hefei, 230601, China. seansean2014@126.com.
authors.forename: Dahai
authors.initials: D
authors.lastname: Liu
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, First Hospital of Jilin University, Changchun, 130021, China. zhuwei3000@hotmail.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
mesh_terms: D045744:Cell Line, Tumor; D058750:Epithelial-Mesenchymal Transition; D015972:Gene Expression Regulation, Neoplastic; D024243:HMGB1 Protein / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D000067759:Receptor for Advanced Glycation End Products / Q000096:biosynthesis* / Q000235:genetics; D053773:Transforming Growth Factor beta1 / Q000235:genetics / Q000378:metabolism*
chemical_list: C000593871:AGER protein, human; D024243:HMGB1 Protein; C585491:HMGB1 protein, human; D009363:Neoplasm Proteins; D000067759:Receptor for Advanced Glycation End Products; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1
keywords: Epithelial–mesenchymal transition (EMT); High-mobility group box-1 (HMGB1); Hypopharyngeal carcinoma; Invasion