Abstract: 【Abstract】 Objective To investigate the effect of overexpression or inhibition of cyclin-dependent kinase 2 （CDK2） on the metabolome of human melanoma cells. Methods The recombinant eukaryotic expression plasmid pcDNA3.1（+）-CDK2+myc was transfected into A375 human melanoma cells for CDK2 overexpression; A375 cells were divided into 3 groups to be treated with the CDK2 inhibitor Roscovitine at final concentrations of 0 （control）, 0.9 and 1.8 μmol/L for 24 hours; Western blot analysis was performed to determine the CDK2 protein expression. An untargeted metabolomics approach was used to investigate metabolomic changes in A375 cells after overexpression or inhibition of CDK2. The number and type of differentially significant metabolites （DSMs）were determined. Correlation analysis, Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway analysis and clustering analysis of representative metabolic pathways were carried out. Results The CDK2 expression level was significantly up-regulated in A375 cells after transfection with the pcDNA3.1（+）-CDK2+myc plasmid, whereas the treatment with 0.9 and 1.8 μmol/L Roscovitine down-regulated its expression. A total of 483 DSMs were identified in CDK2-overexpressed A375 cells, and 306 DSMs were identified in CDK2-inhibited A375 cells; down-regulated DSMs constituted the majority among all DSMs. There were correlations among DSMs such as organic acids and their derivatives, organoheterocyclic compounds, benzenoids, nucleosides/nucleotides and their analogues, as well as correlations between defined and undefined DSMs. The DSMs were mainly involved in metabolic pathways, such as amino acid metabolism and lipid metabolism. The biosynthesis of amino acids, protein digestion and absorption, and aminoacyl-tRNA biosynthesis were common metabolic pathways regulated by overexpression or inhibition of CDK2. However, the types of DSMs involved in these pathways were different. Conclusion Overexpression or inhibition of CDK2 can significantly change the metabolome of A375 cells.

Key words: Melanoma, experimental, Cyclin-dependent kinases, Metabolomics, A375 cells