Background: Glycogen synthase kinase-3β (GSK3β) expression and activity are upregulated in pancreatic cancer tissues. In our previous study, we found that stromal cell-derived factor-1/ chemokine receptor C-X-C motif chemokine receptor 4 (SDF-1α/CXCR4) upregulated matrix metalloproteinase 2 (MMP-2) and promoted invasion in PANC1 and SW-1990 pancreatic cancer cells by activating p38 mitogen-activated protein kinase (p38 MAPK). Additionally, inhibition of GSK3β reduced MMP-2 secretion.
Methods: To investigate the molecular mechanism of GSK3β in pancreatic cancer tissues, we created stable PANC1 cells up-regulation of GSK3β by transfecting GSK3β overexpression plasmid, and down-regulation of GSK3β using two different types of RNA interference.
Results: Western blotting showed that overexpression of GSK3β up-regulated CXCR4 and MMP-2 expression; suppression of GSK3β down-regulated CXCR4 and MMP-2 protein expression. Up-regulation of MMP2 induced by overexpression of GSK3β was blocked by inhibition of CXCR4. Overexpression of GSK3β promoted PANC1 cell invasion, and down-regulation of GSK3β suppressed PANC1 cell invasion in the transwell invasion assays. However, inhibition of CXCR4 using shRNA attenuated the ability of GSK3β to promote PANC1 cell invasion.
Conclusions: This study demonstrated that GSK3β promotes PANC1 cell invasion via the CXCR4/MMP-2 pathway.
Keywords: CXCR4; Glycogen synthase kinase-3β (GSK3β); MMP-2.