Different gDNA content in the subpopulations of prostate cancer extracellular vesicles: Apoptotic bodies, microvesicles, and exosomes

Abstract

BackgroundExtracellular vesicles (EVs) are cell-derived membrane vesicles. EVs contain several RNAs such as mRNA, microRNAs, and ncRNAs, but less is known of their genomic DNA (gDNA) content. It is also unknown whether the DNA cargo is randomly sorted or if it is systematically packed into specific EV subpopulations. The aim of this study was to analyze whether different prostate cancer (PCa) cell-derived EV subpopulations (apoptotic bodies, microvesicles, and exosomes) carry different gDNA fragments.MethodsEV subpopulations were isolated from three PCa cell lines (LNCaP, PC-3, and RC92a/hTERT) and the plasma of PCa patients and healthy donors, and characterized by transmission electron microscopy, nanoparticle tracking analysis and total protein content. gDNA fragments of different genes were detected by real time quantitative PCR and confirmed by DNA sequencing.ResultsWe report that the concentration of EVs was higher in the cancer patients than in the healthy controls. EV subpopulations differed from each other in terms of total protein and DNA content. Analysis of gDNA fragments of MLH1, PTEN, and TP53 genes from the PCa cell-derived EV subpopulations showed that different EVs carried different gDNA content, which could even harbor specific mutations. Altogether, these results suggest that both nucleic acids and proteins are selectively and cell-dependently packed into the EV subtypes.ConclusionsEVs derived from PCa cell lines and human plasma samples contain double-stranded gDNA fragments which could be used to detect specific mutations, making EVs potential biomarkers for cancer diagnostics and prognostics.

Differential fates of biomolecules delivered to target cells via extracellular vesicles

“…Perhaps the difference lies in the fact that chromosomal DNA becomes fragmented primarily during apoptosis, and such fragmentation does not occur in our studies. Interestingly, EVs from cancer patients have recently been shown to contain genomic DNA fragments (25)(26)(27) that may be derived from the fragmented chromosomes of tumor cells undergoing apoptosis.…”

Exosomes and tumor-mediated immune suppression

“…The presence in the TEX cargo of DNA, mRNA, and miRs is important for the role of TEX as information-carrying vehicles. TEX derived from tumor cell lines and EVs from the plasma of cancer patients contain double-stranded genomic DNA (gDNA) (81). Analyses of gDNA fragments of MLH1, PTEN, or TP53 genes showed that different exosomes had distinct gDNA content that could include specific mutations (81,82).…”

“…TEX derived from tumor cell lines and EVs from the plasma of cancer patients contain double-stranded genomic DNA (gDNA) (81). Analyses of gDNA fragments of MLH1, PTEN, or TP53 genes showed that different exosomes had distinct gDNA content that could include specific mutations (81,82). TEX have the ability to carry and transfer oncogenic mutations to recipient cells (83).…”

Large extracellular vesicles carry most of the tumour DNA circulating in prostate cancer patient plasma

“…Some studies have also reported the presence of double stranded genomic DNA (gDNA) in diverse types of EVs [11]. Results from one of the first studies on DNA in EVs demonstrated that different EV populations (apoptotic bodies, microvesicles and exosomes) harbour either TP53 or PTEN mutations [12], suggesting specific EV types might package different parts of the genome. EVs can also carry mitochondrial DNA, retrotransposons and oncogenes (i.e.…”