【作者】 孙兵；

【导师】 李继良；

【作者基本信息】 大连医科大学 ， 外科学， 2004， 硕士

【摘要】 背景:恶性肿瘤是人类死亡的主要原因之一,而且是影响人们生活质量的重要原因。恶性肿瘤的生长和转移不仅依靠肿瘤细胞自身的生物学增殖特性,而且更依赖于新生血管持续不断地为其提供营养和排除代谢产物,以适应其旺盛的新陈代谢的要求。大量的证据表明,肿瘤的生长依赖于新生血管的形成,而且新生血管的形成是肿瘤生长的必需条件;同时新生血管又为肿瘤细胞的浸润转移创造了条件。核糖核酸酶抑制因子(ribonuclease inhibitor,RI)广泛存在于哺乳动物的各种组织器官中,尤以人胎盘中的含量最为丰富。RI是一种分子量为50KD的酸性糖蛋白,其空间构象为“马蹄形”,恰好与“肾形”结构的核糖核酸酶A(RnaseA)及血管形成因子(angiogenin,Ang)紧密结合 ,从而有效地抑制它们的生物学活性 ,特别是Ang的促血管生成的活性受到更强烈的抑制,提示RI可通过抑制Ang的促血管生成活性 ,导致肿瘤得不到氧气、营养物及必要的生长因子而停止生长。并有发现恶性肿瘤患者血中RI的活性明显低于正常 。 目的: 用RT-PCR法 和Western bloting法从蛋白及mRNA水平上对核糖核酸酶抑制因子(RI)在人肺癌及同体癌旁正常肺组织中的表达的检测 ,进一步探讨RI与恶性肿瘤细胞生长的关系。 方法:手术切取26例肺癌及癌旁5厘米以上正常肺组织,液氮速冻,应用Western blotting方法检测人肺癌组织中RI的蛋白表达量;应用RT-PCR的方法检测人肺癌组织中RI的mRNA的表达量。采用χ2检验(chi-square test)分析获得的数据,用SPSS10.0统计软件进行处理。 <WP=5>结果: RI的Western bloting结果:26对标本中24例癌组织中RI的蛋白的表达明显低于癌旁正常肺组织,2例癌组织中RI的蛋白的表达高于癌旁正常肺组织。其中18例鳞癌中,16例癌组织中RI的蛋白的表达明显低于癌旁正常肺组织,2例癌组织中RI的蛋白的表达高于癌旁正常肺组织;8例腺癌中,所有标本癌组织中RI的蛋白的表达均明显低于癌旁正常肺组织。采用配对四格表资料的χ2检验比较肺癌组与正常肺组织组之间RI的蛋白的表达,结果显示肺癌组与正常肺组织组之间有显著性差异(P<0.01);采用四格表的确切概率法比较鳞癌组与腺癌组之间RI的蛋白的表达,结果显示鳞癌组与腺癌组之间RI的蛋白的表达无差异(P>0.1)。RI的RT-PCR的结果: 26对标本中20例癌组织中RI的mRNA含量明显低于癌旁正常肺组织,6例癌组织中RI的mRNA含量高于癌旁正常肺组织。其中18例鳞癌中,14例癌组织中RI的mRNA含量明显低于癌旁正常肺组织,4例癌组织中RI的mRNA含量高于癌旁正常肺组织;8例腺癌中,6例癌组织中RI的mRNA含量明显低于癌旁正常肺组织,2例癌组织中RI的mRNA含量高于癌旁正常肺组织。采用配对四格表资料的χ2检验比较肺癌组与正常肺组织组之间RI的mRNA含量,结果显示肺癌组与正常肺组织组之间有差异(P<0.05);采用四格表的确切概率法比较鳞癌组与腺癌组之间RI的mRNA含量,结果显示鳞癌组与腺癌组之间RI的mRNA含量无差异(P>0.1)。结论:1本研究中所有肺癌及正常肺组织中都有核糖核酸酶抑制因子(RI)的表达。2 肺癌组织中RI的蛋白的表达低于癌旁正常肺组织,鳞癌组织与腺癌组织之间RI的蛋白的表达无差异。3 肺癌组织中RI的mRNA的表达低于癌旁正常肺组织,鳞癌组织与腺癌组织之间RI的mRNA的表达无差异。4核糖核酸酶抑制因子(RI)在肺癌中的表达下调,肺癌的生长可能与RI表达的下调有关,由于RI表达下调,其抑制血管生成因子作用降低,从而可能使癌组织周边新血管的形成未受到有效抑制,使肿瘤得以生长。更多还原

【Abstract】 Background: Malignant tumors are the main diseases that endanger the health and life of human beings and influence the quality of living condition. Malignant proliferation and metastasis are the characteristics of malignant tumors. The growth and metastasis of tumors depend on not only their own biological proliferation character , but also the new blood vessels . The new vessels provides the needed nutrient and removes the metabolism outcome for the tumor cells to adapt the metabolism of tumors. Many studies have demonstrated the link between tumors and new blood vessels on the growth, invasion and metastasis aspects. Ribonuclease inhibitor (RI) is widely spread in the tissues and organs of mammal, especially in placenta. RI is a kind of 50 KD acid glycoprotein, and its horseshoe shape helps its combination tightly with kidney shape RnaseA and angiogenin. This kind of combination can suppress the biological activity of RnaseA and angiogenin, especially angiogenin effectively. This suggestes that RI could inhibit the growth of tumors by suppressing the activity of angiogenin and this function make tumors can not get the needed oxygen ,nutrient and necessary growth factors. It has been demonstrated that the activity of RI in the blood of tumor patients is lower significantly than in normal.Objectives: This study is designed to determine the expression of RI in human lung cancer tissues and the normal tissues beside the pathological changes on the gene and protein level by RT-PCR and Western Blotting. <WP=7>Material and methods: The pathological and normal lung tissues were purchased after operation and were stored in liquid nitrogen immediately. Western blotting was used to examine the protein expression of RI and the result was shown by photograth. RT-PCR was used to detect the mRNA expression of RI and the result was examined by electrophoresis. Chi-square test was used to analyse the experiments data by SPSS 10.0 software.Results: Western bloting of RI Protein : All of the 26 samples showed positive RI expression in this research. 24 samples showed significantly lower RI than the normal lung tissues, while 2 samples showed higher RI expression than normal tissues. In all 18 squamous cell carcinoma samples, 16 samples showed significantly lower RI than the normal lung tissues while 2 samples showed higher RI expression. All 8 adenocarcinoma samples showed significantly lower RI expression. The different expression level of RI between lung cancer tissues and normal lung tissues was significant (P<0.01). The RI expression between squamous cell carcinoma and adenocarcinoma samples had no significance (P>0.1). RT-PCR of RI mRNA: All of the 26 samples showed positive RI mRNA expression in this research. 20 samples showed significantly lower RI mRNA than the normal lung tissues, while 6 samples showed higher RI mRNA expression than normal tissues. In all 18 squamous cell carcinoma samples, 14 samples showed significantly lower RI mRNA than the normal lung tissues while 2 samples showed higher RI mRNA expression. 6 simples in 8 adenocarcinoma samples showed significantly lower RI mRNA expression while 2 samples showed higher RI mRNA expression. The different expression level of RI mRNA between lung cancer tissues and normal lung tissues was significant (P<0.05). The RI mRNA expression between squamous cell carcinoma and adenocarcinoma samples had no significance (P>0.1).<WP=8>Conclusion:1. All the lung cancer tissues showed positive RI protein and mRNA expression in this research.2. The expression of RI protein in lung cancer tissues was significantly lower than normal lung tissues. The RI protein expression between squamous cell carcinoma and adenocarcinoma samples had no significance.3. The expression of RI mRNA in lung cancer tissues was significantly lower than normal lung tissues. The RI mRNA expression between squamous cell carcinoma and adenocarcinoma samples had no significance.4. The expression of RI is declined in lung cancer . The growth of lung cancer is associated with the decline expression更多还原