Objective To evaluate the expression of γ-synuclein protein （SNCG） in carcinoma of bile duct andnormal bile duct tissues， and its clinical significance. Methods The expressions of SNCG were detected by SP immuno-histochemical in 60 cases of cholangiocarcinoma and 34 cases of normal bile duct tissues， and to analysis its relationship with the clinical pathological characteristics of cholangiocarcinoma. Results The positive expression rate of SNCG in carcinoma of bile duct tissues was 73.33% （44/60）， which was higher than that in normal bile duct tissues （P＜0.01）. The positive expression of SNCG in carcinoma of bile duct tissues was correlated with the depth of tumor invasion and lymph node metastasis （P＜0.01）， but not related to patients’ age， gender， and the degree of tumor differentiation （P＞0.05）. Conclusions The expression of SNCG is correlated with the cholangiocarcinoma occurrence， development， invasion， and metastasis. SNCG plays an important role in the infiltration and metastasis of carcinoma of bile duct. SNCG is expected to become a new cancer tumor marker， which can provide a basis to prognosize and to formulate the corres-ponding therapy plan.
Objective To establish perineural invasion xenograft model of hilar cholangiocarcinoma. Methods The cultured cells of cholangiocarcinoma cell line QBC939 were inoculated subcutaneously in the nude mice so as toestablish primary subcutaneous model of cholangiocarcinoma. The primary tumor tissues were inoculated intraperitoneallyaround the liver in the nude mice so as to establish the second generation intraperitoneal xenograft model. The successful xenografted tumor tissues were obtained for anatomical and pathological examinations. Results The tumor formation rate of primary subcutaneous xenograft of hilar cholangiocarcinoma was 100% （5/5）， and no nerve infiltration was observed. The tumor formation rate of the second generation intraperitoneal xenograft was 45% （9/20）， and two mice （2/9， 22%） manifested nerve infiltration. The rate of nerve infiltration was 10% （2/20）， and the tumor cells had different size and diversity， irregular shape， low differentiation， decreased cytoplasm and nucleus karyomegaly， visible atypical and fission phase， and no obvious gland tube structure by pathological examination. Conclusions Hilar cholangiocarcinoma cell has the particular features of perineural invasion， it is a good experiment platform for researching the mode and biological characteristics of perineural invasion of hilar cholangiocarcinoma by applicated QBC939 cell lines to establish the perineural invasion xenograft model of cholangiocarcinoma.
When investing the relationship between independent and dependent variables in dose-response meta-analysis, the common method is to fit a regression function. A well-established model should take both linear and non-linear relationship into consideration. Traditional linear dose-response meta-analysis model showed poor applicability since it was based on simple linear function. We introduced a piecewise linear function into dose-response meta-analysis model which overcame this problem. In this paper, we will give a detailed discussion on traditional linear and piecewise linear regression model in dose-response meta-analysis.