Sonic Hedgehog Expression Correlates With Distant Metastasis in Pancreatic Adenocarcinoma

Objectives: To investigate the expression and clinical significance of Sonic hedgehog (Shh) in pancreatic adenocarcinoma. Methods: The expression of Shh protein was examined in 34 surgical specimens of primary pancreatic adenocarcinoma, 21 nonmalignant specimens of the pancreas by immunohistochemistry streptavidin-perosidase (SP) method. In addition, semiquantitative reverse transcriptase polymerase chain reaction was carried out to analyze Shh mRNA expression in 22 pairs of freshly resected pancreatic adenocarcinoma tissues and their adjacent nontumorous tissues. Results: The positive expression rate of Shh protein was 64.7% (22/34) in 34 surgical specimens of primary pancreatic adenocarcinoma and 0% (0/21) in 21 nonmalignant specimens of the pancreas. The expression rate of Shh was higher in pancreatic adenocarcinoma tissues than that of nonmalignant pancreatic tissues (chi(2) = 22.647, P = 0.000). Sonic hedgehog protein expression correlated with TNM stages and distant metastasis. Moreover, the expression levels of Shh mRNA were higher in pancreatic adenocarcinoma tissues than that of the matched adjacent nontumorous tissues. Conclusions: Sonic hedgehog might play a pivotal role during tumorigenesis of pancreatic adenocarcinoma, and high Shh expression might be associated with the malignant potential of pancreatic cancer.