【作者】 吴琼；

【导师】 王大广；

【作者基本信息】 吉林大学 ， 临床医学（外科学）（专业学位）， 2020， 硕士

【摘要】 应用液相色谱质谱联用技术(LC-MS)对进展期胃癌、早期胃癌和健康人的血液样本进行分析,得出进展期胃癌、早期胃癌、健康人血清样本代谢物代谢谱,找出差异代谢产物。并尝试检验这些标记物对区分胃癌和健康人、早期胃癌和健康人的准确性,为寻找早期胃癌新的生物标志物提供科学依据。方法:1、样本处理:样本采集后14000r/min离心5min,取上清液供LC-MS分析。2、LC-MS分析:通过液相色谱-质谱仪对血清样本进行检测,得到进展期胃癌、早期胃癌和健康人的血液样本代谢图谱和相关原始数据。3、数据处理:采用方差分析、主成分分析、偏最小二乘判别分析、聚类分析等统计方法进行分析,分析胃癌患者和健康人、早期胃癌和健康人的差异代谢产物,绘制ROC曲线验证这些产物对于区分各组的准确性。4、验证组验证:设立独立样本作为验证组,用几种差异代谢物对验证组进行验证、分组和准确性的判断。结果:1、在正负两种离子模式下,得到进展期胃癌、早期胃癌和健康人样本的总离子流程图,可看到各组之间存在峰度值差异;2、通过方差分析,共筛选出316个具有统计学意义的代谢物;主成分分析得分图可以看到各组可以很好的区分开;3、用偏最小二乘判别分析和支持向量机判别分析共得出4个重要差异代谢物;4、绘制ROC曲线显示4种代谢物的面积值均大于0.8,即有较高的准确性。制作含量柱状图可以看出4个代谢物在各组之间存在含量差异。5、以这4种差异代谢物为分组依据对独立样本进行分组,结果显示对进展期胃癌、早期胃癌和健康人具有很好的区分能力。结论:1、精胺、肠抑素、硫酸肝素、三酰甘油在胃癌和健康人之间存在代谢组学差异,可能为潜在生物标记物;2、精胺、肠抑素、硫酸肝素、三酰甘油在早期胃癌与健康人之间存在代谢组学差异,可能为潜在生物标记物;3、精胺、肠抑素、三酰甘油在肿瘤发展中呈降低趋势;硫酸肝素在肿瘤发展中呈先降低后升高的趋势,代谢物的含量变化可能与肿瘤发生发展有关,并可继续探究其代谢机制。更多还原

【Abstract】 Objective:The blood samples of advanced gastric cancer,early gastric cancer and healthy people were analyzed by liquid chromatography-mass spectrometry(lc-ms).The accuracy of these markers in distinguishing gastric cancer from healthy people,early gastric cancer from healthy people was tested to provide scientific basis for the search for new biomarkers for early gastric cancer.Methods:1.Sample processing:Samples were collected and centrifuged at 14000r/min for 5min.The supernatant was taken for lc-ms analysis.2.Lc-ms analysis:We detect the serum samples by liquid chromatography-mass spectrometer,and the metabolic profiles and original data of blood samples of advanced gastric cancer,early gastric cancer and healthy people were obtained.3.Data processing:Variance analysis,principal component analysis,partial least squares discriminant analysis,cluster analysis and other statistical methods were used to analyze the differential metabolites of gastric cancer patients and healthy people,as well as early gastric cancer patients and healthy people,and draw ROC curves to verify the accuracy of these products in differentiating groups.4.Verification group verificationIndependent samples were set up as the verification group,and several different metabolites were used to verify,group and judge the accuracy of the verification group.Results:The total ion flow chart of the samples of advanced gastric cancer,early gastric cancer and healthy people was obtained Under the positive and negative ion modes.A total of 316 metabolites with statistical significance were screened by variance analysis.The score chart of principal component analysis shows that each group can be well separated.Four important differential metabolites were obtained by partial least squares discriminant analysis and support vector machine discriminant analysis.ROC curves were drawn to show that the area values of the four metabolites were all greater than 0.8,indicating high accuracy.The content histogram shows that the contents of the four metabolites are different in each group.These four different metabolites were used as the basis for grouping the independent samples,and the results showed that they had a good ability to distinguish advanced gastric cancer,early gastric cancer and healthy people.Conclusion:There are metabolomic differences between gastric cancer and healthy people,and potential biomarkers include spermine,enterostatin,heparin sulfate,and triacylglycerol.There are metabolomic differences between early and healthy individuals,and potential biomarkers include spermine,enterostatin,heparin sulfate,and triacylglycerol.Spermine,enterostatin and triacylglycerol showed a decreasing trend in tumor development.Heparan sulfate decreased first and then increased in the development of tumor.The change of metabolite content may be related to the development of tumor,and its metabolic mechanism can be further explored.更多还原