OS9 and pancreatic ductal adenocarcinoma: Interestingly, in pancreatic ductal adenocarcinoma (PDAC), another lncRNA ENST00000480739 could inhibit HIF-1α by up-regulating OS9 (osteosarcoma amplified-9) expression through enhancing the acetylation of H3K27 within OS9 gene promoter [60].