Internalization of extracellular double-stranded DNA as a potential marker of cancer stem cells in Epstein–Barr virus-induced B-cell lymphoma

BackgroundAt present, there are no universal markers of tumor stem cells known, including for B-lymphomas. Previously, we have shown that Epstein-Barr virus-induced B-cell lymphoma culture contains cells capable of internalizing TAMRA-labeled DNA. These cells form sphere-forming centers and are essential for the development of xenografts genetically identical to the initial culture.ObjectiveTo analyze the stem characteristics of cells that internalize DNA.MethodsSorting and RNA sequencing of two subpopulations (TAMRA + and TAMRA-) of Epstein-Barr virus-induced B-cell lymphoma culture and a series of quantitative real-time reverse transcription PCR were performed.ResultsTAMRA + cells were shown to have increased synthesis of mRNA of genes associated with the maintenance of a poorly differentiated state (<i>SOX2, NANOG, POU5F1, CYP26A1</i>), self-renewal (<i>FZD5, FZD7, TCF3, LEF1</i>) and epithelial-mesenchymal transition (<i>MMP2, ITGB7</i>). Transcriptomic analysis revealed that in TAMRA + cells, the synthesis of mitochondrial genes, as well as caspases and some apoptosis inhibitors, is reduced. TAMRA + cells possess clonogenic properties, increased level of synthesis of mRNA for key genes associated with self-renewal and poorly differentiated state maintenance.ConclusionsInternalization of the TAMRA-DNA probe is the marker of B-lymphoma cancer stem cells and can be used to detect tumor stem cells and develop new approaches to targeted treatment of B-lymphoma.