Background & objective: Sonic hedgehog (SHH) signaling pathway is important for modulating cellular interaction in the development of mammalian embryo. Epidermal growth factor receptor (EGFR) has been involved in the regulation of cell proliferation and differentiation. Proliferating cell nuclear antigen (PCNA) is an indicator of cell proliferation. This study was to investigate the expression of SHH, EGFR and PCNA in pancreatic cancer, and explore their correlations to cell proliferation.
Methods: The expression of SHH, EGFR, and PCNA in 49 specimens of pancreatic cancer and 49 specimens of normal pancreatic tissues adjacent to cancer was detected by immunohistochemistry. Their interrelations were analyzed.
Results: The positive rates of SHH and EGFR were significantly higher in pancreatic cancer than in normal tissue adjacent to cancer (79.6% vs.14.3%, 73.5% vs.16.3%, P<0.05). The expression of SHH and EGFR in pancreatic cancer had no correlation to patientsoage, tumor size, pathologic type, and tumor site (P>0.05), but were correlated to lymph node metastasis and TNM stage (P<0.05). The strong positive rate of PCNA was significantly higher in pancreatic cancer than in normal tissues (83.7% vs. 20.4%, P<0.05). SHH expression was positively correlated to EGFR expression (r1=0.232, P<0.05). SHH and EGFR expression were positively correlated to PCNA expression(r2=0.412, P<0.05û r3=0.186, P<0.05).
Conclusion: SHH and EGFR signal pathways are active in pancreatic carcinoma, and are closely correlated to cancer cell proliferation.