title: Concomitant induction of apoptosis and autophagy by prostate apoptosis response-4 in hypopharyngeal carcinoma cells.
abstract: The tumor-suppressive activity of prostate apoptosis response-4 (Par-4) has been demonstrated in a variety of human cancers. In this study, for the first time to our knowledge, we demonstrated that a higher intensity of Par-4 was significantly correlated with a better response in patients with hypopharyngeal carcinoma undergoing radiotherapy alone or concurrent chemoradiotherapy. Mechanistically, an elevated expression of Par-4 induced apoptosis of hypopharyngeal carcinoma cells and sensitized cells toward chemotherapeutic agents or X-ray irradiation. Along with apoptotic incitation, intriguingly, autophagic flux also increased on Par-4 stimulation and contributed to cell death. Moreover, the expressions of multiple common regulators involved in apoptosis and autophagy were regulated by Par-4. Taken together, our results suggested a prognostic role of Par-4 in hypopharyngeal carcinoma and showed novel activity of Par-4 in apoptosis and autophagy induction.
authors.affiliation: Institute of Medical Sciences, Tzu-Chi University, Hualien, Taiwan.
authors.forename: Ling-Jung
authors.initials: LJ
authors.lastname: Wang
authors.affiliation: Department of Otolaryngology, Tzu-Chi University, Hualien, Taiwan.
authors.forename: Peir-Rong
authors.initials: PR
authors.lastname: Chen
authors.affiliation: Department of Otorhinolaryngology, Buddhist Tzu Chi General Hospital, Taichung, Taiwan.
authors.forename: Lee-Ping
authors.initials: LP
authors.lastname: Hsu
authors.affiliation: School of Medicine, Tzu-Chi University, Hualien, Taiwan; Department of Radiation Oncology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
authors.forename: Wen-Lin
authors.initials: WL
authors.lastname: Hsu
authors.affiliation: School of Medicine, Tzu-Chi University, Hualien, Taiwan; Department of Radiation Oncology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
authors.forename: Dai-Wei
authors.initials: DW
authors.lastname: Liu
authors.affiliation: Research Center of Excellence for Environment Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Dermatology, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chung-Hsing
authors.initials: CH
authors.lastname: Chang
authors.affiliation: Department of Bioscience Technology, Chung Yuan Christian University, Taoyuan, Taiwan; Center for Nanotechnology, Chung Yuan Christian University, Taoyuan, Taiwan.
authors.forename: Yih-Chih
authors.initials: YC
authors.lastname: Hsu
authors.affiliation: Institute of Medical Sciences, Tzu-Chi University, Hualien, Taiwan; Department of Life Sciences, Tzu-Chi University, Hualien, Taiwan. Electronic address: jwlee@mail.tcu.edu.tw.
authors.forename: Jeng-Woei
authors.initials: JW
authors.lastname: Lee
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D001343:Autophagy; D045744:Cell Line, Tumor; D002470:Cell Survival; D059248:Chemoradiotherapy; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy / Q000648:ultrastructure; D010766:Phosphorylation; D000071456:Sequestosome-1 Protein; D016019:Survival Analysis
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; C099718:SQSTM1 protein, human; D000071456:Sequestosome-1 Protein; C101296:prostate apoptosis response-4 protein