title: MiR-18a increased the permeability of BTB via RUNX1 mediated down-regulation of ZO-1, occludin and claudin-5.
abstract: The purposes of this study were to investigate the possible molecular mechanisms of miR-18a regulating the permeability of blood-tumor barrier (BTB) via down-regulated expression and distribution of runt-related transcription factor 1 (RUNX1). An in vitro BTB model was established with hCMEC/D3 cells and U87MG cells to obtain glioma vascular endothelial cells (GECs). The endogenous expressions of miR-18a and RUNX1 were converse in GECs. The overexpression of miR-18a significantly impaired the integrity and increased the permeability of BTB, which respectively were detected by TEER and HRP flux assays, accompanied by down-regulated mRNA and protein expressions and distributions of ZO-1, occludin and claudin-5 in GECs. Dual-luciferase reporter assay was carried out and revealed RUNX1 is a target gene of miR-18a. Meanwhile, mRNA and protein expressions and distribution of RUNX1 were downregulated by miR-18a. Most important, miR-18a and RUNX1 could reversely regulate the permeability of BTB as well as the expressions and distributions of ZO-1, occludin and claudin-5. Finally, chromatin immunoprecipitation verified that RUNX1 interacted with "TGGGGT" DNA sequence in promoter region of ZO-1, occludin and claudin-5 respectively. Taken together, our present study indicated that miR-18a increased the permeability of BTB via RUNX1 mediated down-regulation of tight junction related proteins ZO-1, occludin and claudin-5, which would attract more attention to miR-18a and RUNX1 as potential targets of drug delivery across BTB and provide novel strategies for glioma treatment.
authors.affiliation: Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001, PR China; Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001, PR China.
authors.forename: Yin-Sha
authors.initials: YS
authors.lastname: Miao
authors.affiliation: Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001, PR China; Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001, PR China.
authors.forename: Ying-Yu
authors.initials: YY
authors.lastname: Zhao
authors.affiliation: Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001, PR China; Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001, PR China.
authors.forename: Li-Ni
authors.initials: LN
authors.lastname: Zhao
authors.affiliation: Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001, PR China; Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001, PR China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004, PR China.
authors.forename: Yun-Hui
authors.initials: YH
authors.lastname: Liu
authors.affiliation: Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001, PR China; Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001, PR China; Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001, PR China. Electronic address: xueyixue888@163.com.
authors.forename: Yi-Xue
authors.initials: YX
authors.lastname: Xue
mesh_terms: D001483:Base Sequence; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D047369:Chromatin Immunoprecipitation; D062507:Claudin-5 / Q000378:metabolism*; D050676:Core Binding Factor Alpha 2 Subunit / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation / Q000235:genetics*; D042783:Endothelial Cells / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D005910:Glioma / Q000235:genetics / Q000473:pathology; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D062793:Occludin / Q000378:metabolism*; D010539:Permeability; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D019108:Tight Junctions / Q000378:metabolism; D062826:Zonula Occludens-1 Protein / Q000378:metabolism*
chemical_list: D062507:Claudin-5; D050676:Core Binding Factor Alpha 2 Subunit; C581632:MIRN18 microRNA, human; D035683:MicroRNAs; D062793:Occludin; D012333:RNA, Messenger; D062826:Zonula Occludens-1 Protein
keywords: Blood–tumor barrier; Claudin-5; Occludin; RUNX1; ZO-1; miR-18a