A urine metabolomics study based on gas chromatography-mass spectrometry (GC-MS) and multivariate statistical analysis was applied to distinguish rat bladder cancer. Urine samples with different stages were collected from animal models, i.e., the early stage, medium stage, and advanced stage of the bladder cancer model group and healthy group. After resolving urea with urease, the urine samples were extracted with methanol and, then, derived with N, O-Bis(trimethylsilyl) trifluoroacetamide and trimethylchlorosilane (BSTFA + TMCS, 99 : 1, v/v), before analyzed by GC-MS. Three classification models, i.e., healthy control vs. early- and middle-stage groups, healthy control vs. advanced-stage group, and early- and middle-stage groups vs. advanced-stage group, were established to analyze these experimental data by using Random Forests (RF) algorithm, respectively. The classification results showed that combining random forest algorithm with metabolites characters, the differences caused by the progress of disease could be effectively exhibited. Our results showed that glyceric acid, 2, 3-dihydroxybutanoic acid, N-(oxohexyl)-glycine, and D-turanose had higher contributions in classification of different groups. The pathway analysis results showed that these metabolites had relationships with starch and sucrose, glycine, serine, threonine, and galactose metabolism. Our study results suggested that urine metabolomics was an effective approach for disease diagnosis.

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气相色谱-质谱联用与随机森林算法相结合的大鼠膀胱癌尿液代谢组学研究

基于气相色谱-质谱（GC-MS）和多元统计分析的尿液代谢组学研究用于区分大鼠膀胱癌。从动物模型即膀胱癌模型组和健康组的早期，中期和晚期阶段收集不同阶段的尿液样本。用脲酶分解尿素后，尿液样品用甲醇萃取，然后用N，O-双（三甲基甲硅烷基）三氟乙酰胺和三甲基氯硅烷（BSTFA + TMCS，99：1，v / v）衍生，然后通过GC-MS分析。建立了三个分类模型，分别是健康对照组与早期和中期组，健康对照组与晚期组，早期和中期组与晚期组，以通过以下方式分析这些实验数据：使用随机森林（RF）算法，分别。分类结果表明，将随机森林算法与代谢物特征相结合，可以有效地表现出疾病进展造成的差异。我们的研究结果表明，甘油酸，2，3-二羟基丁酸，N-（氧己基）-甘氨酸和D- Turanose在不同组的分类中具有较高的贡献。通路分析结果表明，这些代谢产物与淀粉和蔗糖，甘氨酸，丝氨酸，苏氨酸和半乳糖代谢有关。我们的研究结果表明，尿液代谢组学是诊断疾病的有效方法。2、3-二羟基丁酸，N-（氧己基）-甘氨酸和D-turanose在不同组的分类中具有较高的贡献。通路分析结果表明，这些代谢产物与淀粉和蔗糖，甘氨酸，丝氨酸，苏氨酸和半乳糖代谢有关。我们的研究结果表明，尿液代谢组学是诊断疾病的有效方法。2、3-二羟基丁酸，N-（氧己基）-甘氨酸和D-turanose在不同组的分类中具有较高的贡献。通路分析结果表明，这些代谢产物与淀粉和蔗糖，甘氨酸，丝氨酸，苏氨酸和半乳糖代谢有关。我们的研究结果表明，尿液代谢组学是诊断疾病的有效方法。