Determination of Exosome Mitochondrial DNA as a Biomarker of Renal Cancer Aggressiveness

Abstract

Here, the role of non-invasive biomarkers in liquid biopsy was evaluated, mainly in exosomes and mitochondrial DNA (mtDNA) as promising, novel, and stable biomarkers for renal cell carcinoma (RCC). A total of 140 fractions (named from B to F) obtained by ultracentrifugations of whole blood samples from 28 individuals (13 patients and 15 controls) were included. Nanoparticle Tracking Analysis (NTA) was conducted to characterized exosomal fraction. Subsequently, an analysis of digital PCR (dPCR) using the QuantStudio™ 3D Digital PCR platform was performed and the quantification of mtDNA copy number by QuantStudioTM 12K Flex Real-Time PCR System (qPCR) was developed. Moreover, Next Generation Sequencing (NGS) analyses were included using MiSeq system (Illumina, San Diego, CA, USA). An F fraction, which contains all exosome data and all mitochondrial markers, was identified in dPCR and qPCR with statistically significant power (adjusted p values ≤ 0.03) when comparing cases and controls. Moreover, present analysis in mtDNA showed a relevant significance in RCC aggressiveness. To sum up, this is the first time a relation between exosomal mtDNA markers and clinical management of RCC is analyzed. We suggest a promising strategy for future liquid biopsy RCC analysis, although more analysis should be performed prior to application in routine clinical practice.

Small but Mighty—Exosomes, Novel Intercellular Messengers in Neurodegeneration

“…(4) The activity-dependent increase in the number of exosomes released by cells [49] is comparable to gas cells that showed increased nuclear blebbing upon removal of gas from the swim bladder of perch fish [24]. More recently, mitochondrial proteins and DNA were detected in plasma exosomes of some cancer patients and their presence is associated with aggressiveness of the cancer [50,51]. Mitochondrial breakdown is often observed in degenerating cells [52,53].…”

Extracellular vesicles isolated from hyperuricemia patients might aggravate airway inflammation of COPD via senescence-associated pathway

“…Meanwhile, in the present study, the intervention of EVs derived from patients with HUA could increase the expression of cell senescence specific markers (CDKN1A/p21, CDKN2A/p16 and IL-1A) [ 50 , 51 ] and DNA damage response marker 53BP1 proteins [ 52 ] in COPD cell model. Studies have confirmed that mtDNA in outer vesicles can activate the alert state of receptor cells [ 53 , 54 ]. DNA transfer in exosomes has a functional effect on recipient cells and can regulate the unique gene expression pathway in normal recipient cells [ 55 ].…”

Skin Cancer Research Goes Digital: Looking for Biomarkers within the Droplets

“…In the early 2000s, advances in microfluidics and informatics, coupled with novel water-in-oil emulsion systems for sample partitioning, have allowed the development of more sophisticated equipment capable of subdividing PCR reactions into smaller reaction volumes [ 51 ]. Since then, different digital PCR platforms have been released, and are nowadays available, including the microfluidic chamber-based Biomark ® system from Fluidigm [ 52 ], micro-well chip-based Quantstudio 12k/3D ® from Thermo Fisher Scientific [ 53 ], droplet-based QX100 and QX200 Droplet Digital PCR ® from Bio-Rad [ 30 ], the RainDrop dPCR ® from RainDance technologies [ 54 ], the Crystal digital PCR ® from Stilla Technologies [ 55 ], the BEAMing ® technology from Sysmex Inostics [ 56 ], the Lab On An Array (LOAA) Digital PCR ® system from Optolane [ 57 ] and the QIAcuity Digital PCR ® system from Qiagen [ 58 ]. These systems have proven suitable for cancer research, showing similar results in terms of nucleic acid quantification, specificity and sensitivity.…”