H2BC21 and pancreatic adenocarcinoma: Through PPI network construction, we found that several proteins formed the network, including CDK1, ADCY5, GNG7, HIST1H2BJ, VAV3, CXCR5, GRAP2 and HIST2H2BE; 5 of these hub genes (CDK1, ADCY5, GNG7, HIST1H2BJ and GRAP2) were associated with OS, indicating importance of this ceRNA network in PAAD.