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.

The management and screening of prostate cancer (PC) is still the main problem in clinical practice. In this study, we investigated the role of aggressiveness genetic markers for PC stratification. We analyzed 201 plasma samples from PC patients and controls by digital PCR. For selection and validation, 26 formalin-fixed paraffin-embedded tissues, 12 fresh tissues, and 24 plasma samples were characterized by RNA-Seq, immunochemistry, immunofluorescence, Western blot, and extracellular-vesicles analyses. We identified three novel non-invasive biomarkers; all with an increased expression pattern in patients (PCA3: p = 0.002, S100A4: p ≤ 0.0001 and MRC2: p = 0.005). S100A4 presents the most informative AUC (area under the curve) (0.735). Combination of S100A4, MRC2, and PCA3 increases the discriminatory power between patients and controls and between different more and less aggressive stages (AUC = 0.761, p ≤ 0.0001). However, although a sensitivity of 97.47% in PCA3 and a specificity of 90.32% in S100A4 was reached, the detection signal level could be variable in some analyses owing to tumor heterogeneity. This is the first time that the role of S100A4 and MRC2 has been described in PC aggressiveness. Moreover, the combination of S100A4, MRC2, and PCA3 has never been described as a non-invasive biomarker for PC screening and aggressiveness.

Background: Components of liquid biopsy are promising non-invasive biomarkers for monitoring the renal cell carcinoma (RCC) status. Present study tries to evaluate the role of exosomes and mitochondrial DNA (mtDNA) as promise, novel and stable biomarkers that could improve current ones in RCC. Methods: A total of 140 fractions obtained by ultracentrifugations of whole blood samples stored in EDTA anticoagulant from 28 (13 patients and 15 controls) were included in present study. An exosome collection protocol and exhaustive analysis of all phases obtained by ultracentrifugations (named from B to F) was performed. Subsequently, an analysis of dPCR (digital PCR) using the QuantStudio™ 3D Digital PCR platform and the quantification of mtDNA copy number using by QuantStudioTM 12K Flex Real-Time PCR System (qPCR) was developed. Moreover, Next Generation Sequencing (NGS) analyses were included using MiSeq system (Illumina, CA, USA). Results: F fraction, which contains all exosomes´ data and all mitochondrial markers (hypervariable region 1 (HV1) and apocytochrome b of complex III (MT-CYB)) were statistically identified in dPCR and qPCR (p values < 0.05) when a comparison between cases and controls was performed. Moreover, the studied mitochondrial genes shown a relevant significance in RCC aggressiveness analyses (metastasis and stages 4).Conclusions: To sum up, this is the first time a relation between mtDNA genetic markers in exosome and clinical management of RCC is suggested.