Stem cell factor/c-kit signaling enhances invasion of pancreatic cancer cells via HIF-1α under normoxic condition.

The SCF/c-kit signaling plays an important role in invasion of c-kit-expressing tumor cells, however, the molecular mechanisms have not been studied yet. Using a pancreatic cancer model, we demonstrate that SCF/c-kit binding up-regulates the expression of invasion-related genes through the accumulation of HIF-1α. Furthermore, the expression of HIF-1α induced by SCF is not dependent on the oxygen level, but rather on both the PI3K/Akt and Ras/MEK/ERK signaling pathways. In conclusion, under normoxic conditions, SCF/c-kit binding increases expression of HIF-1α through the PI3K/Akt and Ras/MEK/ERK pathways, and the accumulation of HIF-1α up-regulates expression of invasion-related genes that augment the invasiveness of pancreatic cancer, a fatal cancer. Therefore, our results suggest that the inhibition of both c-kit and HIF-1α may be an effective strategy for pancreatic cancer therapy.