Cancer Stem Cells, DNA Methylation and DNA Sequences: Their Diagnostic and Therapeutical Applications

Dear Colleagues,

DNA methylation is an essential epigenetic mechanism for controlling gene expression in both embryonic and adult stem cells. There is a fine-tuned balance between the regulation of gene activation and repression during normal cellular activity, and either hypo- or hypermethylation could induce the expression or inhibition of genes, respectively. Changes in methylation status are acknowledged to be hallmarks for cancer initiation and progression, with the potential to transform normal stem cells into a cancer stem cell (CSC) phenotype. The basic function of the immune system is to provide the host with protection from invading foreign antigens in parallel with the state of self-tolerance, i.e., maintaining its unique antigenic profile. Cellular structures such as nuclei and mitochondria house the vast bulk of DNA. Changes in DNA sequences have gained attention as potential biomarkers since they can be detected as extracellular cell-free DNA (cfDNA) in a wide range of diseases, including cancer. Recently, cfDNA testing has seen a resurgence due to the widespread use of liquid biopsies and the growing need for disease screening, activity monitoring, and drug response assessments. Studies on the immunological effects of cfDNA, in addition to their immunomodulatory or therapeutic advantages, are still in their infancy. The main aim of this Special Issue (Topic) is to discuss the impact of aberrant DNA methylation statuses on CSC functions, including self-renewal, differentiation, drug resistance, and metastasis formation, in addition to analyzing recent findings on the role of different DNA-sensing receptors in the recognition of foreign or self-DNA sequences as potent danger-associated molecular patterns. Further, emphasizing the immunomodulatory as well as pro- and anti-tumor capacities of different DNA sequences, and thus their subsequent potential for anticancer therapy, this Special Issue (Topic) also intends to summarize the results of recent experimental studies.

Dr. Ferenc Sipos
Dr. Györgyi Műzes
Topic Editors