【摘 要】
：
Background: 5-methylcytosine (5-mC) represents an important epigenetic modification involved in development and is frequently altered in cancer (1,2).5-mC can be converted to 5-hydroxymethylcytosine (
【机 构】
：
Key Laboratory of Analytical Chemistry for Biology and Medicine(Ministry of Education),Department of
【出 处】
：
第八届全国微全分析系统学术会议、第三届全国微纳尺度生物分离分析学术会议暨第五届国际微化学与微系统学术会议
论文部分内容阅读
Background: 5-methylcytosine (5-mC) represents an important epigenetic modification involved in development and is frequently altered in cancer (1,2).5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) in an enzymatic process.5-hmC modifications are known to be prevalent in DNA of embryonic stem cells and neurons,but the distribution of 5-hmC in human liver tumor and matched control tissues has not been rigorously explored (3).Methods: We developed an online trapping-capillary hydrophilic interaction liquid chromatography (cHILIC)-in source fragmentation-tandem mass spectrometry (MS/MS) system for quantifying 5-mC and 5-hmC in genomic DNA from hepatocellular carcinoma (HCC) tumor tissues and relevant tumor adjacent tissues.A polymer-based hydrophilic monolithic column was prepared and used for the separation of twelve nucleosides by cHILIC coupled with online trapping system.Limits of detection and quantification (LODs and LOQs),recovery and imprecision of the method were determined.Results: LODs for 5-mC and 5-hmC were 0.06 and 0.19 fmol,respectively,which were,to the best of our knowledge,the lowest compared to other previously reported methods using mass spectrometry.The imprecision and recovery of the cHILIC-ESI-qTOF-MS/MS method were determined with the relative standard deviations (RSDs) and relative errors (REs) being less than 14.9% and 15.8%,respectively.There was a 4-5 fold lower 5-hmC content in HCC tumor tissues compared to tumor adjacent tissues.In addition,5-hmC content highly correlated with tumor stage (Tumor nodes metastasis,p = 0.0002; Barcelona clinic liver cancer,p = 0.0003).Conclusions: The marked depletion of 5-hmC may have profound effects on epigenetic regulation in HCC and could be a potential biomarker for the early detection and prognosis of HCC.
其他文献
In digital microfluidics (DMF),transportation of droplets was determined by the on-off output (0 or 1) of its control system,which applies a voltage on the actuation electrodes underneath and thereby
Sample preparation has been playing an important role in the analysis of complex samples.Mesoporous materials as the promising adsorbents have gained increasing research interest in sample preparation
Microchannel plates (MCP),2.1 cm in diameter,0.40 mm thick,and with 3 million uniform holes 7 microns in diameter,have been used for pumping ethanol,2-propanol,methanol,acetone and water.Pumping start
Nanoparticles of various compositions and structures and with diameters ranging from a few nanometers to 150 nm are the subjects of intensive investigation for the treatment,prevention,and diagnosis o
Recently,micro- or nano-HPLC-MS/MS based techniques have been seen rapid development in proteomics study.However,new materials and techniques for sample preparation are also of great significance to a
Over several decades,there have been continued efforts in biosensors for the sensitive and selective detection of disease biomarkers,environmental toxins and bio-warfare agents,etc.[1,2] However,the s
Gold nanoparticles have unique optical properties arising from their ability to support localized surface plasmonc resonance.Gold nanoparticles are also well-known by their ability to alter the emissi
Fluid mixing is commonly involved in various chemical and biological processes.However,it becomes a challenging task in miniaturized fluidic devices/systems due to increased viscous effects.[1,2] In o
This paper reports a microfluidic microparticles sorting generator by using the optical force and hydrodynamic forces.Micro/Nanoparticles ranging in size from 70 nm to 1 μm can be aligned and focused
Single nanopore has drawn wide attention due to its potentials for DNA sequencing,single molecule detection,molecular transport studies,etc.Mainly two types of nanopores can be recognized: soft nanopo