GPC1 and chronic pancreatitis: To confirm the aberrant expression of GPC1 at the transcriptional level, an immunohistochemistry assay was performed in normal pancreata (n = 2), chronic pancreatitis (n = 4), nontumor pancreata tissues (n = 169), PDAC (n = 186), metastases (n = 4) and metastatic lymph nodes (n = 7).