title: Transcriptome-Based Analysis of Molecular Pathways for Clusterin Functions in Kidney Cells.
abstract: Clusterin (CLU) is a chaperone-like protein and plays a protective role against renal ischemia-reperfusion injury (IRI); however, the molecular pathways for its functions in the kidney are not fully understood. This study was designed to investigate CLU-mediating pathways in kidney cells by using bioinformatics analysis. CLU null renal tubular epithelial cells (TECs) expressing human CLU cDNA (TEC-CLU(hCLU) ) or empty vector (TEC-CLU(-/-) ) were exposed to normoxia or hypoxia (1% O2 ). Transcriptome profiling with a significant twofold change was performed using SurePrint G3 Mouse Gene Expression 8 × 60 K microarray, and the signaling pathways was ranked by using Ingenuity pathway analysis. Here, we showed that compared to CLU null controls, ectopic expression of human CLU in CLU null kidney cells promoted cell growth but inhibited migration in normoxia, and enhanced cell survival in hypoxia. CLU expression affected expression of 3864 transcripts (1893 up-regulated) in normoxia and 3670 transcripts (1925 up-regulated) in hypoxia. CLU functions in normoxia were associated mostly with AKT2/PPP2R2B-dependent PI3K/AKT, PTEN, VEGF, and ERK/MAPK signaling and as well with GSK3B-mediated cell cycle progression. In addition to unfolded protein response (UPR) and/or endoplasmic reticulum (ER) stress, CLU-enhanced cell survival in hypoxia was also associated with PIK3CD/MAPK1-dependent PI3K/AKT, HIF-α, PTEN, VEGF, and ERK/MAPK signaling. In conclusion, our data showed that CLU functions in kidney cells were mainly mediated in a cascade manner by PI3K/AKT, PTEN, VEGF, and ERK/MAPK signaling, and specifically by activation of UPR/ER stress in hypoxia, providing new insights into the protective role of CLU in the kidney. J. Cell. Physiol. 231: 2628-2638, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Experimental Medicine Program, Graduate School, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Ghida
authors.initials: G
authors.lastname: Dairi
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Qiunong
authors.initials: Q
authors.lastname: Guan
authors.affiliation: Vancouver Prostate Centre, Vancouver, BC, Canada.
authors.forename: Mani
authors.initials: M
authors.lastname: Roshan-Moniri
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Vancouver Prostate Centre, Vancouver, BC, Canada.
authors.forename: Colin C
authors.initials: CC
authors.lastname: Collins
authors.affiliation: Vancouver Prostate Centre, Vancouver, BC, Canada.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ong
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Vancouver Prostate Centre, Vancouver, BC, Canada.
authors.forename: Martin E
authors.initials: ME
authors.lastname: Gleave
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Christopher Y C
authors.initials: CY
authors.lastname: Nguan
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Caigan
authors.initials: C
authors.lastname: Du
mesh_terms: D000818:Animals; D015687:Cell Hypoxia / Q000235:genetics; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation; D002470:Cell Survival / Q000235:genetics; D051152:Clusterin / Q000235:genetics* / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007668:Kidney / Q000378:metabolism*; D008810:Mice, Inbred C57BL; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics*; D059467:Transcriptome / Q000235:genetics*
chemical_list: D051152:Clusterin; D020033:Protein Isoforms; C494922:Akt2 protein, mouse; D051057:Proto-Oncogene Proteins c-akt