Figure 1. PARP inhibition down-regulates vimentin expression and inhibits endothelial-to-mesenchymal transition in HUVECs.

Cell extracts from HUVEC either treated with vehicle or 40 µM DPQ were subjected to 2D electrophoresis as described in Materials and Methods. Image analysis software (DeCyder) indicated that seven proteins exhibited decreased expression in HUVEC treated with DPQ compared to untreated cells. Proteins were identified using MALDI-TOF. Spots labeled with arrows indicate proteins that were identified by mass spectrometry (see Figure 2). (A) The spot with the arrow is vimentin. (B) PARP inhibition reduced the expression of both vimentin and Snail1 and up-regulated VE-cadherin in human endothelial cells (HUVEC) as determined by immunoblotting, indirect immunofluorescence (C), and mRNA levels (D). PARP inhibition decreased HUVEC cell migration (E). (**P<0.01, ***P<0.001 PARP inhibitor groups versus DPQ).