title: Expression of Y-Box binding protein-1 following hypericin-mediated photodynamic therapy in well-differentiated nasopharyngeal cancer in vivo.
abstract: The Y-Box binding protein, YB-1, belongs to a group in the DNA and RNA binding protein family. YB-1 is known to be expressed in a number of different cancers and reported to protect cells against DNA-damaging agents such as ultraviolet light. The purpose of this study was to determine if YB-1 levels are altered in photodynamic therapy (PDT)-treated nasopharyngeal cancer (NPC) cells. In this report, we show for the first time that YB-1 is expressed at both the mRNA and protein levels in well-differentiated NPC in vivo. YB-1 mRNA expression in tumor tissues from a murine well-differentiated HK1/NPC model showed no significant difference in mRNA levels following hypericin-PDT. Localization of the YB-1 protein by immuno-histochemistry revealed the presence of cytoplasmic YB-1 in the more mature and better differentiated cells of the untreated group, as well as cells that survived PDT treatment. Expression of the YB-1 protein may possibly influence the cellular stress response to hypericin-PDT and protect the cells from phototoxicity.
authors.affiliation: Department of Anatomy, National University of Singapore, Singapore.
authors.forename: Hong-Yan
authors.initials: HY
authors.lastname: Du
authors.forename: Malini
authors.initials: M
authors.lastname: Olivo
authors.forename: Ying-Jie
authors.initials: YJ
authors.lastname: Chen
authors.forename: George
authors.initials: G
authors.lastname: Yip
authors.forename: Puay-Hoon
authors.initials: PH
authors.lastname: Tan
authors.forename: Ken
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Masafumi
authors.initials: M
authors.lastname: Tsujimoto
authors.forename: Boon-Huat
authors.initials: BH
authors.lastname: Bay
mesh_terms: D000818:Animals; D000873:Anthracenes; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002277:Carcinoma / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009303:Nasopharyngeal Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D010569:Perylene / Q000031:analogs & derivatives* / Q000627:therapeutic use; D010778:Photochemotherapy; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D011838:Radiation-Sensitizing Agents / Q000627:therapeutic use*
chemical_list: D000873:Anthracenes; D000970:Antineoplastic Agents; D012333:RNA, Messenger; D011838:Radiation-Sensitizing Agents; D010569:Perylene; C004965:hypericin