摘要目的 探讨胰腺导管腺癌(PDAC)中Gli1、MDM2和p53表达的相关性及临床病理意义.方法 应用免疫组化方法检测57对配对的PDAC及癌旁组织石蜡标本中Gli1、MDM2和p53蛋白表达水平,观察其与患者临床病理参数的关系；再以实时定量聚合酶链反应(qRT-PCR)检测14对配对冷冻保存的新鲜PDAC标本中Gli1 mRNA表达水平.siRNA干扰进一步检测三者之间的相关性.结果 免疫组化结果显示,Gli1、MDM2和p53在癌组织中表达(分别为50.9％、57.9％、56.1％)明显高于配对的癌旁组织(分别为33.3％、26.3％、17.5％,t=2.413、2.848、2.960,均P＜0.05)；Gli1表达与肿瘤TNM分期(x2 =8.211,P=0.004)、浸润深度(x2=4.247,P=0.039)及MDM2表达(r=0.299,x2=5.105,P=0.024)相关；MDM2和p53表达分别与胰腺癌浸润深度及TNM分期相关(x2=5.182,P=0.023；x2=5.696,P=0.017).单因素及多因素分析发现,Gli1是影响胰腺癌患者预后的一个独立危险因素(RR=2.290,95％ CI:1.051 ～4.992,P=0.037),并且含Gli1和MDM2共同表达的胰腺癌患者预后更差(P =0.034).Gli1在14例PDAC标本中mRNA表达水平同样高于癌旁组织(t =2.926,P=0.012)；在p53突变型AsPC-1细胞中,Gli1敲除引起MDM2的下调,但p53蛋白表达不受影响.反之,在p53野生型Capan-2细胞中,Gli1敲除同时引起p53的上调及MDM2的下调.结论 Gli1、MDM2和p53在胰腺癌中均呈高表达,并有助于判断胰腺癌患者的预后.Gli1能够调控MDM2及野生型p53表达.三者可能共同参与了胰腺癌的发生进展.

abstractsObjective To study the clinicopathological significance and relationship of Gli1,MDM2 and p53 expression in human pancreatic cancer.Methods The expression of Gli1,MDM2 and p53 proteins in 57 paired paraffin embedded pancreatic ductal adenocarcinoma (PDAC) specimens and adjacent non-cancerous pancreatic tissues was detected by immunohistochemistry.The relationship between their expression and clinicopathological characters was analyzed.Quantitative real-time PCR (qRT-PCR) was used to examine the expression of Gli1 mRNA level in 14 paired fresh PDAC specimens and adjacent noncancerous panereatic tissues.siRNA interference were used to further detect the close relationship among them.Results IHC showed the expression of Gli1 (50.9％),MDM2 (57.9％) and p53 (56.1％) was increased in 57 cases of pancreatic cancer compared to that in paired normal pancreatic tissues (33.3％,26.3％ and 17.5％ respectively,t =2.413,2.848 and 2.960,all P ＜ 0.05).Gli1 expression was positively associated with tumor TNM stage (x2 =8.211,P =0.004),invasion depth (x2 =4.247,P =0.039) and MDM2 expression (r =0.299,x2 =5.105,P =0.024),while expression of MDM2 and p53 was associated with tumor invasion depth (x2 =5.182,P =0.023) and TNM stage (x2 =5.696,P =0.017),respectively.Univariate and multivariate analysis revealed that Gli1 was an independent adverse prognostic indicator for patients with PDAC (RR =2.290,95％ CI:1.051-4.992,P =0.037),and patients with Gli1 and MDM2 co-expression had a significantly poorer overall survival than patients with their negative expression (P =0.034).Gli1 mRNA expression was much higher in 14 cases of PDAC than that in adjacent normal pancreatic tissues (t =2.926,P =0.012).In p53 mutant AsPC-1 cells,Gli1 knockdown down regulated MDM2,but had no effect on p53 expression,whereas Gli1 knockdown down regulated MDM2 and up regulated p53 protein levels in p53 wild-type Capan-2 cells.Conclusions Gli1,MDM2 and p53 are overexpressed in PDAC,and are benefit for predicting patients' prognosis.Gli1 can regulate MDM2 and wildtype p53 expression.Their co-expression might coordinately contribute to the development and progression of PDAC.