Background: Overexpression of vascular endothelial growth factor-C (VEGF-C) has been found to play an important role in malignant progression of various cancer cells, in addition to lymphangiogenesis. However, the mechanisms involved are still largely unknown. Our early research has confirmed that the expression of VEGF-C in bladder cancer was markedly higher than that in normal bladder tissues. VEGF-C can also obviously promote proliferation and invasion of bladder cancer T24 cells. In the present work, we attempted to use proteomic analysis to screen out potential VEGF-C-associated proteins involved in malignant progression of the bladder cancer T24 cells.
Material/Methods: Lentivirus vector-based RNA interference (RNAi) was employed to diminish VEGF-C expression of bladder cancer T24 cells. Then we performed comparative proteome analysis to explore differentially expressed proteins in T24 cells with and without VEGF-C siRNA, by two-dimensional difference gel electrophoresis (2D-DIGE).
Results: Twenty-three proteins were identified. Some proteins (matrix metalloproteinase-9, Keratin 8, Serpin B5, Annexin A8) with significant differences were further confirmed by Western blotting.
Conclusions: The 23 potential VEGF-C-associated proteins identified in our study provide us with further insights into the mechanism of VEGF-C promoting malignant progression of bladder cancer cells.

Keywords: Two-Dimensional Difference Gel Electrophoresis, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Reproducibility of Results, RNA, Small Interfering - metabolism, Proteomics - methods, Neoplasm Proteins - metabolism, Matrix Metalloproteinase 9 - metabolism, Blotting, Western, Urinary Bladder Neoplasms - pathology, Vascular Endothelial Growth Factor C - pharmacology