Objective    To study the role and mechanism of protein kinase D3 (PKD3) in promoting migration and invasion of non-small cell lung cancer (NSCLC) cells.      Methods    Human NSCLC A549 cells were infected with a high titer of Ade-LacZ

Ade-PKD3 or Ade-PKD3-DN adenovirus or transfected with siRNA of non-specific control (si-CTL) and siRNA of PKD3 (si-PKD3)

respectively. Exp

ression of PKD3

MT1-MMP

MMP-2 mRNAs  and proteins in NSCLC A549 cells was detected by real-time RT-PCR and Western blot analysis

respectively. Migration of A549 cells infected with adenovirus or transfected with siRNA was detected at different time points by wound healing assay.      Results    The titer of Ade-LacZ

Ade-PKD3 or Ade-PKD3-DN adenovirus reached 2.4×10

9

3.0×10

9

and 3.2×10

9

PFU/ml

respectively. Western blotting showed that the PKD3 or dominant negative mutant PKD3 (PKD3-DN) was over-expressed. The migration level of A549 cells infected with Ade-PKD3 was significantly higher than that of those infected with Ade-LacZ in 4 and 20 h after cell scratching (P0.01)

whereas dramatically reduced after infection with Ade-PKD3-DN in 8 and 20 h after cell scratching (P0.01). Furthermore

PKD3 knocked down by siRNA transfection not only inhibited the migration of A549 cells in 16

24 and 36 h after cell scratch

but also down-regulated the expression of MT1-MMP

MMP-2 at mRNA and protein levels.     Conclusion    Expression of PKD3 can significantly increase the migration of NSCLC A549 cells by up-regulating the expressions of MT1-MMP and MMP-2 .