Expression of RECK in pancreatic carcinoma and its relationship with prognosis / 中华肝胆外科杂志

ABSTRACT

Objective To study the expression of reversion-inducing-cysteine-rich protein with Kazal motifs (RECK) in human pancreatic carcinoma tissues and pancreatic carcinoma cell lines; the effects of recombinant lentiviruses carrying RECK gene(LV-RECK) therapy on human pancreatic carcinoma xenograft in nude mice; and to find out the relationship between the expression of RECK and the prognosis of pancreatic carcinoma.Methods Immunohistochemical method was used to detect the expression of RECK in the resected specimens of pancreatic carcinoma and their corresponding normal pancreatic tissues in 42 patients.Western blotting was used to examine the expression of RECK in human pancreatic carcinoma cell lines (PANC-1,MIAPaCa-2,AsPC-1).Statistical analyses were performed to determine the relationship between RECK expression and the clinicopathological characteristics and prognosis in pancreatic carcinoma.Subcutaneous xenograft tumor models of human pancreatic carcinoma were established in nude mice.These nude mice were then divided into the experimental group,the negative control group and the blank control group randomly.The three groups of nude mice were intratumorally injected with LV-RECK,LV-EGFP and normal saline (NS) respectively.The antitumor effect was studied.Immunohistochemical method was used to detect the expression of RECK and microvessel density (MVD).Terminal deoxynucleotidyl transferase mediated dUTP-DIG nick end labeling (TUNEL) was used to detect the apoptosis of tumor cells.Survival analysis was performed.Results All three pancreatic carcinoma cell lines did not express RECK.The overall positive rate of RECK expression was 45.2 ％ (19/42) in pancreatic carcinoma,and 88.1 ％ (37/42) in normal pancreatic tissue.The expression level of RECK was significantly lower in the tumor tissues than in the normal tissues (P＜0.01).The expression of RECK was significantly associated with TNM stage,lymph node metastasis and local infiltration of pancreatic carcinoma (P＜0.05).Kaplan-Meier survival analysis revealed that the survival time was significantly longer in the RECK positive patient group than in the RECK negative patient group.Univariate Cox regression analysis revealed that RECK expression,TNM stage,lymph node metastasis and local infiltration were significantly related with prognosis for pancreatic carcinoma (P＜0.05).Multivariate Cox regression analysis revealed that only RECK expression remained as an independent significant factor in predicting the prognosis of pancreatic carcinoma (P ＜ 0.001).When compared with the negative control and the blank control groups,the volume of subcutaneous xenograft tumor in the experimental group was significantly decreased (P＜0.05).RECK protein in the experimental group was re-expressed.MVD of the experimental group was significantly less than those of the control groups (P＜0.05).Apoptotic index (AI)of the experimental group was significantly higher than those of the control groups (P＜0.05).The survival time of nude mice in the experimental group was significantly longer than those in the control groups (P＜0.05).Conclusions RECK expression was closely related to invasion,metastasis and prognosis of pancreatic carcinoma and it was an independent prognostic marker.RECK gene over-expression inhibited neovascularization of pancreatic carcinoma,induced apoptosis of tumor cells,inhibited the growth of tumor xenograft and improved the prognosis of tumor-bearing mice.These results suggest a possible new treatment for pancreatic carcinoma.