mir-218 modulates ARF6 expression and inhibits pancreatic ductal adenocarcinoma invasion

Background Pancreatic ductal adenocarcinoma is an extremely malignant disease with the majority of patients having metastatic disease upon diagnosis. Recently, it was shown the SLIT2 plays a regulatory role in melanoma invasion through the control of invadopodia. Therefore, we sought to determine the mechanism behind miR-218 inhibition of pancreatic cancer invasion. Methods mir-218 target genes were discovered using three miRNA target prediction websites. Modulation of mir-218 target ARF6 was determined by transfection with antagomirs and mimics to mir-218. Pancreatic cancer migration and invasion were measured using Boyden chamber assays. Invasion was further measured using matrix degradation assays. Results We found that mir-218 modulates ARF6 RNA and protein expression in pancreatic cancer. mir-218 did not inhibit pancreatic cancer cell migration, but did inhibit invasion. mir-218 did not affect the formation of invadopodia in pancreatic cancer cells, but did inhibit the total area of matrix degradation caused by functional invadopodia. Conclusions This work suggests that miR-218 is a suppressor of pancreatic ductal adenocarcinoma invasion through a pathway that regulates invadopodia maturation.