Data_Sheet_1_Quantitative Analysis of Methylated Adenosine Modifications Revealed Increased Levels of N6-Methyladenosine (m6A) and N6,2′-O-Dimethyladenosine (m6Am) in Serum From Colorectal Cancer and Gastric Cancer Patients.docx

Colorectal cancer and gastric cancer are the most prevalent gastrointestinal malignancies worldwide, and early detection of these cancers is crucial to reduce their incidence and mortality. RNA methylation plays an important regulatory role in a variety of physiological activities, and it has drawn great attention in recent years. Methylated adenosine (A) modifications such as N6-methyladenosine (m6A), N1-methyladenosine (m1A), 2′-O-methyladenosine (Am), N6,2′-O-dimethyladenosine (m6Am), and N6,N6-dimethyladenosine (m62A) are typical epigenetic markers of RNA, and they are closely correlated to various diseases including cancer. Serum is a valuable source of biofluid for biomarker discovery, and determination of these adenosine modifications in human serum is desirable since they are emerging biomarkers for detection of diseases. In this work, a targeted quantitative analysis method using hydrophilic interaction liquid chromatography–tandem mass spectrometry (HILIC-MS/MS) was developed and utilized to analyze these methylated adenosine modifications in serum samples. The concentration differences between the healthy volunteers and cancer patients were evaluated by Mann–Whitney test, and receiver operator characteristic (ROC) curve analysis was performed to access the potential of these nucleosides as biomarkers. We demonstrated the presence of the m6Am in human serum for the first time, and we successfully quantified the concentrations of A, m6A, m1A, and m6Am in serum samples from 99 healthy controls, 51 colorectal cancer patients, and 27 gastric cancer patients. We found that the levels of m6A and m6Am in serum were both increased in colorectal cancer or gastric cancer patients, compared to that in healthy controls. These results indicate that m6A and m6Am in serum may act as potential biomarkers for early detection and prognosis of colorectal cancer and gastric cancer. In addition, the present work will stimulate investigations on the effects of adenosine methylation on the initiation and progression of colorectal cancer and gastric cancer.

结直肠癌和胃癌是全球范围内最为常见的胃肠道恶性肿瘤，而这些癌症的早期检测对于降低其发病率和死亡率至关重要。RNA甲基化在各种生理活动中发挥着重要的调控作用，近年来引起了广泛关注。甲基化的腺苷（A）修饰，如N6-甲基腺苷（m6A）、N1-甲基腺苷（m1A）、2'-O-甲基腺苷（Am）、N6,2'-O-二甲基腺苷（m6Am）以及N6,N6-二甲基腺苷（m62A），是RNA的典型表观遗传标记，且与包括癌症在内的多种疾病密切相关。血清作为生物标志物发现的重要生物流体来源，测定人类血清中这些腺苷修饰的存在具有重要意义，因为它们是检测疾病的潜在生物标志物。在本研究中，开发并利用了一种基于亲水性相互作用液相色谱-串联质谱（HILIC-MS/MS）的靶向定量分析方法，用于分析血清样本中的甲基化腺苷修饰。通过Mann-Whitney检验评估了健康志愿者与癌症患者之间的浓度差异，并进行了接受者操作特征（ROC）曲线分析，以评估这些核苷作为生物标志物的潜力。我们首次在人类血清中检测到m6Am的存在，并成功定量了来自99名健康对照者、51名结直肠癌患者和27名胃癌患者的血清样本中A、m6A、m1A和m6Am的浓度。我们发现，与健康对照组相比，结直肠癌或胃癌患者的血清中m6A和m6Am的水平均有所升高。这些结果表明，血清中的m6A和m6Am可能作为结直肠癌和胃癌早期检测及预后评估的潜在生物标志物。此外，本研究将激发对腺苷甲基化在结直肠癌和胃癌发生和发展过程中影响的研究。