摘要Background Considerable evidence suggests that phosphatase of regenerating liver-3 (PRL-3) plays multiple roles in cancer metastasis; however,the molecular mechanisms remain largely unknown.The aim of this study was to identify proteins associated with PRL-3-promoted colon cancer metastasis,by comparative proteomic analysis.Methods Proteomes of human colon cancer LoVo cells transfected with PRL-3 gene (LoVo-PRL-3) or empty vector PAcGFP-C3 (LoVo-control) were compared using 2D gel electrophoresis.Proteins that varied significantly in concentration were selected and identified using mass spectrometry.Expression of translationally controlled tumor protein (TCTP) mRNA and protein in LoVo-PRL-3 and LoVo-control cells was detected by real-time PCR and Western blotting.Small interfering RNA (siRNA) targeting TCTP was used for silencing TCTP expression in LoVo-PRL-3 cells.Functional significance of TCTP in PRL-3-promoted colon cancer cell proliferation,migration and invasion was investigated by Cell Counting Kit-8 assay and transwell chamber.Results Seventeen proteins displaying significant and reproducible differences between LoVo-PRL-3 and LoVo-control cells were identified.Ten proteins were upregulated and seven were downregulated in LoVo-pRL-3 cells when compared with LoVo-control cells.Eight identified proteins are associated with distinct steps of tumor metastasis:ubiquitin-like protein ISG15,interleukin-18,TCTP,serpin B5,annexin A3,macrophage-capping protein,ATP-dependent RNA helicase DDX3X,and cathepsin D.Real-time PCR and Western blotting results showed that both TCTP mRNA and protein were significantly increased in LoVo-PRL-3 cells compared to LoVo-control cells.Transfection with TCTP siRNA significantly reduced the expression of both mRNA and protein levels of TCTP in LoVo-PRL-3 cells.Knockdown of TCTP by siRNA inhibited PRL-3-promoted proliferation,migration and invasion of LoVo-PRL-3 cells.Conclusion Our results imply that TCTP might be a mediator of PRL-3-promoted proliferation,migration and invasion of human colon cancer cells.