title: Histone demethylase RBP2 promotes lung tumorigenesis and cancer metastasis.
abstract: The retinoblastoma binding protein RBP2 (KDM5A) is a histone demethylase that promotes gastric cancer cell growth and is enriched in drug-resistant lung cancer cells. In tumor-prone mice lacking the tumor suppressor gene RB or MEN1, genetic ablation of RBP2 can suppress tumor initiation, but the pathogenic breadth and mechanistic aspects of this effect relative to human tumors have not been defined. Here, we approached this question in the context of lung cancer. RBP2 was overexpressed in human lung cancer tissues where its depletion impaired cell proliferation, motility, migration, invasion, and metastasis. RBP2 oncogenicity relied on its demethylase and DNA-binding activities. RBP2 upregulated expression of cyclins D1 and E1 while suppressing the expression of cyclin-dependent kinase inhibitor p27 (CDKN1B), each contributing to RBP2-mediated cell proliferation. Expression microarray analyses revealed that RBP2 promoted expression of integrin-β1 (ITGB1), which is implicated in lung cancer metastasis. Mechanistic investigations established that RBP2 bound directly to the p27, cyclin D1, and ITGB1 promoters and that exogenous expression of cyclin D1, cyclin E1, or ITGB1 was sufficient to rescue proliferation or migration/invasion, respectively. Taken together, our results establish an oncogenic role for RBP2 in lung tumorigenesis and progression and uncover novel RBP2 targets mediating this role.
authors.affiliation: Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang, Taipei, 115, Taiwan.
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Teng
authors.forename: Cheng-Feng
authors.initials: CF
authors.lastname: Lee
authors.forename: Ying-Shiuan
authors.initials: YS
authors.lastname: Li
authors.forename: Yi-Ren
authors.initials: YR
authors.lastname: Chen
authors.forename: Pei-Wen
authors.initials: PW
authors.lastname: Hsiao
authors.forename: Meng-Yu
authors.initials: MY
authors.lastname: Chan
authors.forename: Feng-Mao
authors.initials: FM
authors.lastname: Lin
authors.forename: Hsien-Da
authors.initials: HD
authors.lastname: Huang
authors.forename: Yen-Ting
authors.initials: YT
authors.lastname: Chen
authors.forename: Yung-Ming
authors.initials: YM
authors.lastname: Jeng
authors.forename: Chih-Hung
authors.initials: CH
authors.lastname: Hsu
authors.forename: Qin
authors.initials: Q
authors.lastname: Yan
authors.forename: Ming-Daw
authors.initials: MD
authors.lastname: Tsai
authors.forename: Li-Jung
authors.initials: LJ
authors.lastname: Juan
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000201:enzymology* / Q000473:pathology; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000378:metabolism*; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D018450:Disease Progression; D005260:Female; D055785:Gene Knockdown Techniques; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology* / Q000473:pathology; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D009361:Neoplasm Invasiveness / Q000473:pathology*; D009362:Neoplasm Metastasis; D020411:Oligonucleotide Array Sequence Analysis; D054840:Retinol-Binding Proteins, Cellular / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D023041:Xenograft Model Antitumor Assays
chemical_list: C518459:RBP2 protein, human; D054840:Retinol-Binding Proteins, Cellular