title: Vitamin D3 analogue EB1089 inhibits the proliferation of human laryngeal squamous carcinoma cells via p57.
abstract: The objective of this study is to evaluate the role of the cyclin-dependent kinase inhibitor p57 in EB1089-inhibited proliferation of human laryngeal squamous carcinoma cells (HEp-2). HEp-2 cells were treated with the vitamin D3 analogue EB1089 for 48 h and total RNA was extracted for reverse transcription-PCR amplification using primers for the p57 coding sequence. Proteins were detected by Western blot analysis. For interference using silencing RNA (siRNA), HEp-2 cells were transfected with siRNA specific for p57 (siRNA-p57) or a negative control sequence (siRNA-con) followed by treatment with 10 nmol/L EB1089. The effects of EB1089 on cell proliferation were evaluated by 5-bromo-2'-deoxyuridine incorporation and '3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide assay. Cell death and cell cycle dynamics were monitored using flow cytometry. EB1089 significantly inhibited HEp-2 cell proliferation and increased p57 mRNA and protein levels; this was blocked by siRNA-p57 but not by siRNA-con. The EB1089-induced suppression of HEp-2 cell proliferation recovered to near-normal levels with siRNA-p57 transfection. EB1089 inhibits the proliferation of HEp-2 cells and p57 plays an important role in this.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, People's Republic of China.
authors.forename: Lianjun
authors.initials: L
authors.lastname: Lu
authors.forename: Jianhua
authors.initials: J
authors.lastname: Qiu
authors.forename: Shunli
authors.initials: S
authors.lastname: Liu
authors.forename: Wenjing
authors.initials: W
authors.lastname: Luo
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002117:Calcitriol / Q000031:analogs & derivatives* / Q000627:therapeutic use; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects; D050761:Cyclin-Dependent Kinase Inhibitor p57 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007822:Laryngeal Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D034741:RNA, Small Interfering / Q000378:metabolism; D013997:Time Factors; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; C493964:CDKN1C protein, human; D050761:Cyclin-Dependent Kinase Inhibitor p57; D034741:RNA, Small Interfering; D002117:Calcitriol; C078903:seocalcitol