Recent advances in DNA methylation in tumorigenesis and diagnosis

DNA methylation is the process of adding a methyl group to the 5'-carbon of the cytosine residue in the CpG dinucleotide sequence, and it is one of the key components of epigenetic modifications. DNA methylation occurs alongside various biological processes. Abnormal DNA methylation is often associated with the onset of various severe diseases. As a century-old problem that threatens human life, in-depth studies of tumors have revealed abundant evidence of dysregulated DNA methylation. Numerous studies have indicated that DNA hypermethylation tends to impact the transcription of many tumor suppressor genes, leading to the immortalization of tumor cells. In this review, we systematically summarize the progression of DNA methylation in tumor types with currently high incidence rates. We also summarize the current clinical methods of DNA methylation detection and treatment, and provide an in-depth analysis of the advantages and limitations of these methods. In addition, we discuss the future limitations and challenges facing DNA methylation research, aiming to advance its clinical application in tumor diagnosis and treatment.