Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Aberrant choline metabolism in epithelial ovarian cancer: relevance of choline kinase activity and expression

ABSTRACT: Detection of the abnormal phosphatidylcholine (PtdCho) metabolism in EOC by analysis of magnetic resonance profile (MRS), showed a significant increase of PCho content in EOC cells as compared with non tumoral counterparts associated with activation of choline kinase (ChoK), the enzyme responsible for PCho production following choline phosphorylation in the PtdCho biosynthetic pathway (Kennedy’s pathway). The α-isoform of ChoK has an essential role in growth control and signal transduction and it has been implicated in the carcinogenic process. Aim of the study is the evaluation of the biological relevance of ChoK expression and activity to define its possible role as a non-invasively detectable EOC biomarker and druggable target. We specifically silenced ChoKα expression by transient RNA interference in two different EOC cell lines and evaluated the biological effects related to metabolic profiles, cell proliferation, cell cycle regulation and alteration of global gene expression to possibly identify new pathways implicated in altered choline metabolism. Following ChoKα silencing we observed a 70% reduction of mRNA and protein expression with a similar reduction in PCho accumulation as assessed by HMRS analysis. The ChoKα silencing was accompanied by 20% inhibition of cell growth and similar percentage of cells blocked in the G1-phase of cell cycle. No alteration in cell morphology and modulation of the main survival signaling pathways (PI3K and MAPK-related signaling) were observed. By gene expression analysis we found 476 differentially expressed genes (p< 0.01; FDR 25%) in silenced cells. By transcriptome analysis of CHKA silenced cells as compared to controls, among the most relevant co-repressed genes we found CyclinA, related to regulation of cell cycle progression, and cytokines genes (IL-6 and IL-8) related to inflammation and EOC aggressiveness. Acyl-CoA synthetase medium-chain family member 3 (ACSM3), phosphatidic acid phosphatase type 2 (PPAP2A) and Osteoprotegerin were among the most up-regulated genes. All co-modulated genes have been validated by RTqPCR also in independent biological replicates. Ingenuity System Pathways Analysis (IPA) identified a network of molecules most significantly affected by CHKA silencing whose main functions is related to cell morphology cellular assembly and organization, cellular function and maintenance. Also, the cellular functions predicted to be mostly affected by silencing were cellular movement and cell death that are expected to be respectively decreased and increased in silenced cells. a total of 12 samples were analyzed: Two EOC cell line SKOV3 and INTOV11 were transiently silenced with unrelated or CHKA-specific siRNA pool. Three independent experiment were run for each cell line.

ORGANISM(S): Homo sapiens

SUBMITTER: Loris De Cecco

PROVIDER: E-GEOD-39943 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Choline kinase-alpha by regulating cell aggressiveness and drug sensitivity is a potential druggable target for ovarian cancer.

Granata A A Nicoletti R R Tinaglia V V De Cecco L L Pisanu M E ME Ricci A A Podo F F Canevari S S Iorio E E Bagnoli M M Mezzanzanica D D

British journal of cancer 20131126 2

<h4>Background</h4>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).<h4>Methods</h4>To assess its biological relevance, ChoK-alpha expression was downmodulated by transient RNA interference in EOC in vitro models. Gene expres ...[more]

PMID: 24281000

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Dataset Information

Aberrant choline metabolism in epithelial ovarian cancer: relevance of choline kinase activity and expression

Publications

Choline kinase-alpha by regulating cell aggressiveness and drug sensitivity is a potential druggable target for ovarian cancer.

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