Accumulating evidence in recent years indicates that DNA methylation(5-methyl-2-deoxycytidine,5-mdC) and hydroxymethylation(5-hydroxymethyl-2-deoxycytidine, 5-hmd C) have been implicated in various biological processe...Accumulating evidence in recent years indicates that DNA methylation(5-methyl-2-deoxycytidine,5-mdC) and hydroxymethylation(5-hydroxymethyl-2-deoxycytidine, 5-hmd C) have been implicated in various biological processes, and the aberrations of these DNA cytosine modifications is tightly associated with cancer. N6-methyl-2-deoxyadenosine(m~6dA), as a newly discovered epigenetic modification in genome of mammals, has been demonstrated to play vital regulatory roles in tumorigenesis. However, the content information of m~6dA in human tumor tissues is still limited and pan-cancer analysis of these DNA epigenetic modifications is lacked. Herein, we developed a sensitive and robust stable isotopediluted hydrophilic interaction liquid chromatography-tandem mass spectrometry(HILIC-MS/MS) method for accurate quantification of m~6dA, 5-mdC and 5-hmdC in genomic DNA from 82 pairs of human tumor tissues and matched tumor-adjacent normal tissues. The types of tumors included esophagus cancer, lung cancer, breast cancer, liver cancer, pancreatic cancer, gastric cancer, stromal tumor and colorectal cancer.Compared to the normal tissues, we revealed the level of m6dA was increased in tumor tissues of esophagus cancer, lung cancer and liver cancer, whereas the level of m~6dA was diminished in tumor tissues of pancreatic cancer and gastric cancer;while the contents of 5-mdC and 5-hmdC exhibited significant decrease in tumor tissues of most types of cancer. It is worth noting that we revealed, for the first time,the content of genomic m~6dA in pancreatic cancer, stromal tumor and colorectal cancer. The significant changes of these DNA epigenetic modifications indicate they may serve as indicators of cancers. In addition, this study will benefit for better understanding of the regulatory roles of these DNA epigenetic modifications in cancers.展开更多
基金sponsored by Strategic Priority Research Program of the Chinese Academy of Science[grant No.XDA17010106]the National Key Research and Development Program of China[grant Nos.2018YFC1505703 and 2018YFC1506704].
基金financially supported by National Natural Science Foundation of China (No. 22176167)the Key R&D Program of Zhejiang Province (No. 2021C03125)Natural Science Foundation of Zhejiang Province (No. LY19B050007)。
文摘Accumulating evidence in recent years indicates that DNA methylation(5-methyl-2-deoxycytidine,5-mdC) and hydroxymethylation(5-hydroxymethyl-2-deoxycytidine, 5-hmd C) have been implicated in various biological processes, and the aberrations of these DNA cytosine modifications is tightly associated with cancer. N6-methyl-2-deoxyadenosine(m~6dA), as a newly discovered epigenetic modification in genome of mammals, has been demonstrated to play vital regulatory roles in tumorigenesis. However, the content information of m~6dA in human tumor tissues is still limited and pan-cancer analysis of these DNA epigenetic modifications is lacked. Herein, we developed a sensitive and robust stable isotopediluted hydrophilic interaction liquid chromatography-tandem mass spectrometry(HILIC-MS/MS) method for accurate quantification of m~6dA, 5-mdC and 5-hmdC in genomic DNA from 82 pairs of human tumor tissues and matched tumor-adjacent normal tissues. The types of tumors included esophagus cancer, lung cancer, breast cancer, liver cancer, pancreatic cancer, gastric cancer, stromal tumor and colorectal cancer.Compared to the normal tissues, we revealed the level of m6dA was increased in tumor tissues of esophagus cancer, lung cancer and liver cancer, whereas the level of m~6dA was diminished in tumor tissues of pancreatic cancer and gastric cancer;while the contents of 5-mdC and 5-hmdC exhibited significant decrease in tumor tissues of most types of cancer. It is worth noting that we revealed, for the first time,the content of genomic m~6dA in pancreatic cancer, stromal tumor and colorectal cancer. The significant changes of these DNA epigenetic modifications indicate they may serve as indicators of cancers. In addition, this study will benefit for better understanding of the regulatory roles of these DNA epigenetic modifications in cancers.