【作者】 黄勇；

【导师】 郑树；

【作者基本信息】 浙江大学 ， 肿瘤学， 2012， 硕士

【摘要】 研究背景：基质金属蛋白酶7(MMP7)是基质金属蛋白酶家族的成员,编码基因定位于llq21-q22,是Wnt/β-catenin信号通路的靶基因之一。MMP7是其家族中分子量最小的分泌性蛋白,不同于家族中的其他成员,其在肿瘤组织中主要由肿瘤细胞而非基质细胞分泌。有研究表明MMP7能够通过作用于Fas／FasL通路而影响正常凋亡信号的传导,从而能使肿瘤细胞逃避杀伤性T细胞(CTL)的杀伤性作用,在肿瘤的发生发展中发挥着重要的作用。有报道显示Fas/FasL信号通路在肿瘤细胞对5-fu治疗的敏感性中同样发挥着重要的作用。在大肠癌中,特别是对于TNM分期Ⅱ期和Ⅲ期的病人,术后哪些应该接受以5-fu为基础的化疗仍然有待进一步明确。MMP7是否能够影响大肠癌细胞对5-FU的敏感性以及在Ⅱ期和Ⅲ期患者中其是否能作为判断预后的预测因子目前仍然不清楚。目的：探讨MMP7对大肠癌细胞5-FU敏感性的影响及其在Ⅱ期和Ⅲ期大肠癌患者中的表达,并分析其表达的量与患者预后之间的关系。方法：基因芯片检测52例大肠癌及其中26例癌旁组织中MMP7mRNA的表达,免疫组化检测76例TNM分期为Ⅱ期和Ⅲ期的大肠癌患者癌组织和癌旁组织MMP7蛋白表达的不同。MTT、克隆形成实验和流式细胞学的方法检测在体外外源性的加入重组人MMP7蛋白对大肠癌细胞5-FU敏感性的影响。免疫组织化学的方法检测MMP7在Ⅱ期和Ⅲ期大肠癌患者癌组织及癌旁组织表达的情况,并统计分析MMP7的表达与患者在术后接受5-FU治疗后的DFS之间的关系。结果：基因芯片和免疫组化显示肿瘤组织MMP7的表达显著高于癌旁组织。在体外,外源性的加入重组人MMP7蛋白能够减少大肠癌细胞SW620,HT29及RKO对5-FU的敏感性。在Ⅱ期和Ⅲ期大肠癌中,MMP7主要表达于肿瘤组织,MMP7高表达的患者的DFS显著比低表达的差。COX多因素风险比例模型分析显示MMP7为独立的预后预测因子。结论：在大肠癌中,MMP7能够降低大肠癌细胞对5-FU的敏感性,MMP7的表达量可以作为Ⅱ期和Ⅲ期大肠癌患者预后不良的一个潜在的预测因子。更多还原

【Abstract】 Background:Matrix metalloproteinase7(MMP7) is a member of a Zinc-dependent endopeptidases family (MMPs). It located in11q21-q22and it is one of the target genes of WNT/β-Catenin signal pathway. Distinguished from other members, MMP7is the smallest one containing only the common catalytic domain and zinc binding region and it is secreted mainly by tumor cells instead of matrix cells in tumors. Current studies suggest that it plays an important role on tumor development by acting on Fas/Fasl signal pathway to influence Fas-mediated apoptosis and making tumor cells escape from the killing of CTL. Because Fas/Fasl signal pathway has also been suggested to play an important role on5-FU sensitivity of tumor cells, it is still unclear whether MMP7can influence the5-FU sensitivity of colorectal cancer cells. In colorectal cancer, It is hard to determine which CRC patients should receive adjuvant chemotherapy, especially for those in stag Ⅱ and Ⅲ. it is also unclear whether MMP7can act as a predictor of prognosis. Purpose:To explore the influence of MMP7to5-FU sensitivity of colorectal cancer cells and the relationship between its expression and the prognosis of stag Ⅱ and Ⅲcolorectal cancer patients which taken5-FU based adjacent chemotherapy after tumor resection.Method:To test the different expression of MMP7in tumor tissue and its adjacent tissue by gene chip and IHC. MTT,colony-forming unit assays and Flow cytometry was taken to test the influence of MMP7to5-FU sensitivity of colorectal cancer cells in vitro. IHC was carried out to determine the expression of MMP7in stag II and III colorectal cancer patients, the relationship between the prognosis of patients and the expression of MMP7was analyzed by SPSS17.0software.Result:MMP7was mainly expressed by tumor tissue not adjacent normal tissue, High expression of MMP7was observed in46of total76cancer samples (60.5%).while in adjacent tissue, only5of total76(6.6%) was detected high MMP7expression. MMP7decreases the susceptibility to5-FU in all three colon cancer cells. Compared to low expression, high MMP7expression was significant related to decrease5-year survival, this was confirmed in univariate analysis based on the cox proportional hazards model (p=0.007). The expression of MMP7was significantly related with disease-free survival in patients with stage Ⅱ and Ⅲ according to Kaplan-Meier curve.Cox proportional hazards was taken to determine whether MMP7was an independent prognostic marker. Conclusion:MMP7can decrease the susceptibility to5-FU in colon cancer cells and MMP7was a potential prognostic marker for patients with stage Ⅱ and Ⅲ colorectal cancer.更多还原