Identification And Application Of Metabolic-related Markers For Clinically Important Diseases Based On Mass Spectrometry

Background: The screening of clinically important diseases is crucial for the diagnosis,treatment and prevention of diseases,and often can reduce the cost of late treatment,improve the prognosis,and even avoid the occurrence of harm.Early screening and prevention of diseases through the detection of early metabolic or diagnostic markers by specific techniques has become an important part of the modern public health services,such as newborn screening for inherited metabolic diseases,and also becomes an important direction for current translational medicine.Objective: This study attempts to use mass spectrometry to find metabolic or screening markers for clinically common diseases,hemoglobinopathy and prostatic carcinoma(PCa),in order to establish new methods for rapid,high-throughput and low-cost screening of the diseases,to achieve early screening and prevention of hemoglobinopathy and PCa.Methods:(1)We used liquid chromatography-tandem mass spectrometry(LC-MS/MS)to analyze the hemoglobin in patients with hemoglobinopathy,in order to establish a method for microhemoglobin extraction from dried blood spot(DBS)samples.With the use of tryptic cleavage,we selected and identified marker peptides of ?-thalassemia(HbH),?-thalassemia,abnormal hemoglobin diseases(HbE,HbC)and other types of hemoglobin disease,and attempted establish a novel method for efficiently screening of hemoglobin disease based on LC-MS/MS.(2)We also used LC-MS/MS and gas chromatography-mass spectrometry(GC-MS)to analyze more than 110 metabolites such as amino acid,acylcarnitine,and organic acid in blood or urine from PCa patients,as well as culture medium fron different line of PCa cells treated with certain drug,to select the tumor specific biomarkers,then the clinical value of the biomarkers for screening and prognosis of Pca were also evaluated.Results:(1)More than 1600 clinical samples confirmed with hemoglobinopathy were collected.A method for extracting micro hemoglobin from dry blood spot(DBS)samples was successfully established.Specific peptides of ? thalassaemia(HbH),? thalassemia,and abnormal hemoglobin disease(HbE)were analyzed and identified,then a LC-MS/MS based method was developed to qualitatively and quantitatively analyze the specific peptides,and use for hemoglobinopathy screening.Method evaluation has confirmed the performance of the new LC-MS/MS method.(2)By analyzing the blood and urine metabolites in 55 patients with PCa,several amino acid,acyl carnitine,and organic acid-specific metabolites were identified.Method validation was performed to evaluate the clinical application of these abnormal metabolites in diagnosis and classification of PCa.We then confirmed the tumor specificity of the abnormal metabolites through an in-vitro study,and provided a foundation for further establishment of the diagnostic or screening methods for PCa.Conclusion:(1)The LC-MS/MS method used for hemoglobin disease,especially thalassemia screening,has a sensitivity and specificity of more than 98%,and a fast speed for sampling(<60 seconds/case),which turns out to be high throughput,but with low cost.(2)Present study has found different kinds of abnormal metabolites in blood and urine from PCa patients,and the tumor specificity were also confirmed.Our study preliminary revealed the metabolic characteristics of PCa cells,and lays foundation for further exploration of the pathological mechanism and treatment for PCa.