title: Choline kinase-alpha by regulating cell aggressiveness and drug sensitivity is a potential druggable target for ovarian cancer.
abstract: BACKGROUND
  Aberrant choline metabolism has been proposed as a novel cancer hallmark. We recently showed that epithelial ovarian cancer (EOC) possesses an altered MRS-choline profile, characterised by increased phosphocholine (PCho) content to which mainly contribute over-expression and activation of choline kinase-alpha (ChoK-alpha).
  
  
  METHODS
  To assess its biological relevance, ChoK-alpha expression was downmodulated by transient RNA interference in EOC in vitro models. Gene expression profiling by microarray analysis and functional analysis was performed to identify the pathway/functions perturbed in ChoK-alpha-silenced cells, then validated by in vitro experiments.
  
  
  RESULTS
  In silenced cells, compared with control, we observed: (I) a significant reduction of both CHKA transcript and ChoK-alpha protein expression; (II) a dramatic, proportional drop in PCho content ranging from 60 to 71%, as revealed by (1)H-magnetic spectroscopy analysis; (III) a 35-36% of cell growth inhibition, with no evidences of apoptosis or modification of the main cellular survival signalling pathways; (IV) 476 differentially expressed genes, including genes related to lipid metabolism. Ingenuity pathway analysis identified cellular functions related to cell death and cellular proliferation and movement as the most perturbed. Accordingly, CHKA-silenced cells displayed a significant delay in wound repair, a reduced migration and invasion capability were also observed. Furthermore, although CHKA silencing did not directly induce cell death, a significant increase of sensitivity to platinum, paclitaxel and doxorubicin was observed even in a drug-resistant context.
  
  
  CONCLUSIONS
  We showed for the first time in EOC that CHKA downregulation significantly decreased the aggressive EOC cell behaviour also affecting cells' sensitivity to drug treatment. These observations open the way to further analysis for ChoK-alpha validation as a new EOC therapeutic target to be used alone or in combination with conventional drugs.
authors.affiliation: Unit of Molecular Therapies, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Granata
authors.affiliation: Unit of Molecular Therapies, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Nicoletti
authors.affiliation: Unit of Molecular Therapies, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Tinaglia
authors.affiliation: Unit of Functional Genomics, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy.
authors.forename: L
authors.initials: L
authors.lastname: De Cecco
authors.affiliation: Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
authors.forename: M E
authors.initials: ME
authors.lastname: Pisanu
authors.affiliation: Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Ricci
authors.affiliation: Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Podo
authors.affiliation: 1] Unit of Molecular Therapies, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy [2] Unit of Functional Genomics, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Canevari
authors.affiliation: Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Iorio
authors.affiliation: Unit of Molecular Therapies, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Bagnoli
authors.affiliation: Unit of Molecular Therapies, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Mezzanzanica
mesh_terms: D000077216:Carcinoma, Ovarian Epithelial; D016923:Cell Death / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000235:genetics; D049109:Cell Proliferation / Q000187:drug effects; D002794:Choline / Q000235:genetics / Q000378:metabolism; D002797:Choline Kinase / Q000235:genetics* / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D004317:Doxorubicin / Q000494:pharmacology; D005260:Female; D006801:Humans; D050356:Lipid Metabolism / Q000187:drug effects / Q000235:genetics; D058990:Molecular Targeted Therapy; D009375:Neoplasms, Glandular and Epithelial / Q000188:drug therapy* / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D017239:Paclitaxel / Q000494:pharmacology; D010767:Phosphorylcholine / Q000378:metabolism; D010984:Platinum / Q000494:pharmacology; D034622:RNA Interference / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects; D059467:Transcriptome
chemical_list: D010767:Phosphorylcholine; D010984:Platinum; D004317:Doxorubicin; C517212:CHKA protein, human; D002797:Choline Kinase; D002794:Choline; D017239:Paclitaxel