Burton Casey, Shi Honglan, Ma Yinfa
Department of Chemistry and Center for Biomedical Science & Engineering, MO University of Science and Technology, Rolla, MO 65409, United States.
Department of Chemistry and Center for Biomedical Science & Engineering, MO University of Science and Technology, Rolla, MO 65409, United States.
Clin Chim Acta. 2014 Aug 5;435:42-7. doi: 10.1016/j.cca.2014.04.022. Epub 2014 May 2.
Urinary biomarkers, such as pteridines, require normalization with respect to an individual's hydration status and time since last urination. Conventional creatinine-based corrections are affected by a multitude of patient factors whereas urine specific gravity (USG) is a bulk specimen property that may better resist those same factors. We examined the performance of traditional creatinine adjustments relative to USG to six urinary pteridines in aggressive and benign breast cancers.
6-Biopterin, neopterin, pterin, 6-hydroxymethylpterin, isoxanthopterin, xanthopterin, and creatinine were analyzed in 50 urine specimens with a previously developed liquid chromatography-tandem mass spectrometry technique. Creatinine and USG performance were evaluated with non-parametric Mann-Whitney hypothesis testing.
USG and creatinine were moderately correlated (r=0.857) with deviations occurring in dilute and concentrated specimens. In 48 aggressive and benign breast cancers, normalization by USG significantly outperformed creatinine adjustments which marginally outperformed uncorrected pteridines in predicting pathological status. In addition, isoxanthopterin and xanthopterin were significantly higher in pathological specimens when normalized by USG.
USG, as a bulk property, can provide better performance over creatinine-based normalizations for urinary pteridines in cancer detection applications.
尿生物标志物，如蝶啶，需要根据个体的水合状态和上次排尿后的时间进行标准化。传统的基于肌酐的校正受多种患者因素影响，而尿比重（USG）是一种总体标本特性，可能更能抵抗这些相同因素。我们研究了在侵袭性和良性乳腺癌中，相对于USG，传统肌酐校正对六种尿蝶啶的性能。
采用先前开发的液相色谱-串联质谱技术分析了50份尿液标本中的6-生物蝶呤、新蝶呤、蝶呤、6-羟甲基蝶呤、异黄蝶呤、黄蝶呤和肌酐。通过非参数曼-惠特尼假设检验评估肌酐和USG的性能。
USG与肌酐呈中度相关（r=0.857），在稀释和浓缩标本中出现偏差。在48例侵袭性和良性乳腺癌中，在预测病理状态方面，USG标准化显著优于肌酐校正，而肌酐校正略优于未校正的蝶啶。此外，当通过USG标准化时，病理标本中的异黄蝶呤和黄蝶呤显著更高。
在癌症检测应用中，USG作为一种总体特性，在尿蝶啶的基于肌酐的标准化方面比肌酐具有更好的性能。
