Expression And Significance Of Neural Cadherin In Perihilar Cholangiocarcinoma

Objective：To explore neural cadherin (N-cadherin) expressions in perihilarcholangiocarcinoma, and to determine their potential interest in clinicalmanifestation. Methods：A total of26surgically resected human perihilarcholangiocarcinoma specimens were recruited from Hepatobiliary andPancreatic Surgery Division in our hospital, including19males and7females,with an average age of58±9years old（range:36–82years）. None of thepatients had received chemotherapy and/or radiotherapy before Operation. Allthe cases were confirmed as perihilar cholangiocarcinoma by histopathology. Of26cases, perineural invasion were positive in9cases, and negative in17cases.12/26of cases had lymphatic metastasis. American Joint Committee onCancer stage distribution was as follows: stage I (n=8), stageII-IV (n=18).10/26cases were low differentiated perihilar cholangiocarcinoma,16cases were inmiddle and well differentiated group.（1）We immunohistochemically examinedthe expression of neural cadherin in perihilar cholangiocarcinoma (n=26) andparaneoplastic tissues(n=26)and normal bile duct tissues(n=5). Expression ofN-cadherin in the tumors was defined according to the proportion of positivecells: negative (≤10%of tumor cells positive),positive(＞10%of tumor cells positive);（2）We also evaluated the expression of N-cadherin in perihilarcholangiocarcinoma and paraneoplastic tissues by western blotting. Level ofN-cadherin expression were measured as the ratio to-actinprotein.All data using SPSS17statistical software for statistical processing,measurement data were expressed as means±SD.Chi-square test or Fisher’sexact test were conducted to test whether there was significant differencebetween two groups of enumeration data. Student’s t test was used to find thedifference between two groups of measurement data. The level of significancewas set at P<0.05. Results:（1）N-cadherin in perihilar cholangiocarcinomatissue showed a membranous and cytoplasm staining of the cancer cells;N-cadherin expression was observed in14of26perihilar cholangiocarcinomaand in6of26paraneoplastic tissues (53.84%vs23.08%, χ2=5.200，P<0.05).N-cadherin expression was negative in normal bile duct tissues. The positiverate of N-cadherin expression in low differentiated group was higher than that inmiddle and well differentiated group.There was no significant difference inthe positive expression rate of N-cadherin between cancerous tissues withperineural invasion and cancerous tissues without perineural invasion. Nostatistically significant correlation between N-cadherin expression and tumorsize, tumor stag and age was observed（2）The western blotting showedsignificantly higher N-cadherin expression in the perihilar cholangiocarcinomathan in the paraneoplastic tissues (0.88±0.12vs0.43±0.09, P<0.05).Conclusion:N-cadherin may be involved in the occurrence and development of perihilarcholangiocarcinoma.Hight level expression of N-cadherin appears to beassociated with poor differention.