We selected five S100 genes (S100A2/A10/A11/A14/A16 by using the above analysis, which were highly expressed in PAAD and associated with poor prognosis and chemoresistance of PAAD, for further differential expression analysis between the high (top 25 percentile) and low samples (bottom 25 percentile). The gene discussed is S100A2; the disease is pancreatic adenocarcinoma.