PDE8A and familial pancreatic carcinoma: For instance, tumor-released exosomal circ-PDE8A promotes invasive growth via the miR-338/MACC1/MET pathway in pancreatic cancer [26]; exosomal circRNA derived from gastric tumor promotes white adipose browning by targeting the miR-133/PRDM16 pathway [27]; and exosomal circ100284 regulates the cell cycle by acting as a sponge of miR-217 [28].