title: Reduced cohesin destabilizes high-level gene amplification by disrupting pre-replication complex bindings in human cancers with chromosomal instability.
abstract: Gene amplification is a hallmark of cancer with chromosomal instability although the underlying mechanism by which altered copy numbers are maintained is largely unclear. Cohesin, involved in sister chromatid cohesion, DNA repair, cell cycle progression and transcriptional regulation of key developmental genes, is frequently overexpressed in human cancer. Here we show that cohesin-dependent change in DNA replication controls the copy numbers of amplified genes in cancer cells with chromosomal instability. We found that the down-regulation of elevated cohesin leads to copy number-associated gene expression changes without disturbing chromosomal segregation. Highly amplified genes form typical long-range chromatin interactions, which are stabilized by enriched cohesin. The spatial proximities among cohesin binding sites within amplified genes are decreased by RAD21-knockdown, resulting in the rapid decline of amplified gene expression. After several passages, cohesin depletion inhibits DNA replication initiation by reducing the recruitment of pre-replication complexes such as minichromosome maintenance subunits 7 (MCM7), DNA polymerase α, and CDC45 at replication origins near the amplified regions, and as a result, decreases the DNA copy numbers of highly amplified genes. Collectively, our data demonstrate that cohesin-mediated chromatin organization and DNA replication are important for stabilizing gene amplification in cancer cells with chromosomal instability.
authors.affiliation: Cancer Research Institute, Seoul National University, Seoul 110-799, Republic of Korea Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 110-799, Republic of Korea.
authors.forename: Jiyeon
authors.initials: J
authors.lastname: Yun
authors.affiliation: Cancer Research Institute, Seoul National University, Seoul 110-799, Republic of Korea.
authors.forename: Sang-Hyun
authors.initials: SH
authors.lastname: Song
authors.affiliation: Cancer Research Institute, Seoul National University, Seoul 110-799, Republic of Korea Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 110-799, Republic of Korea.
authors.forename: Jee-Youn
authors.initials: JY
authors.lastname: Kang
authors.affiliation: Cancer Research Institute, Seoul National University, Seoul 110-799, Republic of Korea.
authors.forename: Jinah
authors.initials: J
authors.lastname: Park
authors.affiliation: Cancer Research Institute, Seoul National University, Seoul 110-799, Republic of Korea Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 110-799, Republic of Korea.
authors.forename: Hwang-Phill
authors.initials: HP
authors.lastname: Kim
authors.affiliation: Cancer Research Institute, Seoul National University, Seoul 110-799, Republic of Korea Department of Internal Medicine, Seoul National University Hospital, Seoul 110-744, Republic of Korea.
authors.forename: Sae-Won
authors.initials: SW
authors.lastname: Han
authors.affiliation: Cancer Research Institute, Seoul National University, Seoul 110-799, Republic of Korea Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 110-799, Republic of Korea Department of Internal Medicine, Seoul National University Hospital, Seoul 110-744, Republic of Korea kimty@snu.ac.kr.
authors.forename: Tae-You
authors.initials: TY
authors.lastname: Kim
mesh_terms: D001665:Binding Sites; D000076246:CCCTC-Binding Factor; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D002842:Chromatids / Q000737:chemistry / Q000378:metabolism; D002843:Chromatin / Q000737:chemistry / Q000378:metabolism; D043171:Chromosomal Instability; D020090:Chromosome Segregation; D055028:Comparative Genomic Hybridization; D004256:DNA Polymerase I / Q000235:genetics / Q000378:metabolism; D004261:DNA Replication; D004268:DNA-Binding Proteins; D005784:Gene Amplification; D018628:Gene Dosage; D015972:Gene Expression Regulation, Neoplastic; D045325:HCT116 Cells; D056945:Hep G2 Cells; D006801:Humans; D064168:Minichromosome Maintenance Complex Component 7 / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D010750:Phosphoproteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
chemical_list: D000076246:CCCTC-Binding Factor; C113571:CDC45 protein, human; C000619697:CTCF protein, human; D018797:Cell Cycle Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; C429022:RAD21 protein, human; D034741:RNA, Small Interfering; D012097:Repressor Proteins; D004256:DNA Polymerase I; C101624:MCM7 protein, human; D064168:Minichromosome Maintenance Complex Component 7