PDE8A and neoplasm: For example, tumor cells release exosomal circ-PDE8A that in turn facilitates invasive advances in a miR-338-MET transcriptional regulator MACC1-MET protooncogene receptor tyrosine pathway-dependent manner in pancreatic cancer cells, showing that the invasiveness of tumor is enhanced by the transfer of circ-PDE8A facilitated by exosomes (Li Z. H. et al., 2018).