CDC6: A novel canine tumour biomarker detected in circulating extracellular vesicles

Extracellular Vesicles
/References

Andriessen, Anneloes, Laura Bongiovanni, Tom A. P. Driedonks, Elsbeth Liere, Anne Seijger, Charlotte V. Hegeman, Sebastiaan A. Nimwegen, et al. 2021. “CDC6 : A Novel Canine Tumour Biomarker Detected in Circulating Extracellular Vesicles.” Veterinary and Comparative Oncology, November. https://doi.org/10.1111/vco.12781.

Circulating nucleic acids and extracellular vesicles (EV) represent novel biomarkers to diagnose cancer. The non-invasive nature of these so-called liquid biopsies provides an attractive alternative to tissue biopsy-based cancer diagnostics. This study aimed to investigate if circulating cell cycle-related E2F target transcripts can be used to diagnose tumours in canine tumour patients with different types of tumours. Furthermore, we assessed if these mRNAs are localised within circulating EV. We isolated total RNA from the plasma of 20 canine tumour patients and 20 healthy controls. Four E2F target genes (CDC6, DHFR, H2AFZ and ATAD2) were selected based on the analysis of published data of tumour samples available in public databases. We performed reverse transcription and quantitative real-time PCR to analyse the plasma levels of selected E2F target transcripts. All four E2F target transcripts were detectable in the plasma of canine tumour patients. CDC6 mRNA levels were significantly higher in the plasma of canine tumour patients compared to healthy controls. A subset of canine tumour patient and healthy control plasma samples (n = 7) were subjected to size exclusion chromatography in order to validate association of the E2F target transcripts to circulating EV. For CDC6, EV analysis enhanced their detectability compared to total plasma analysis. In conclusion, our study reveals circulating CDC6 as a promising non-invasive biomarker to diagnose canine tumours.

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Background Previous studies found that cigarette smoke (CS) exposure could induce NSCLC malignancy and miRNA dysregulation. Yet, the association of CS-induced miRNA dysregulation and NSCLC malignancy has not been clearly understood. This study aimed to evaluate the effect of CS exposure in smokers on the expression of miR-10b-5p and miR-320b in extracellular vesicles (EVs) from NSCLC patients. Material and methods Bioinformatic analysis was conducted to validate miRNA candidates. Blood and tissue samples were collected from NSCLC patients (n = 21) with smoking and non-smoking history. EVs were isolated from plasma and miRNAs were extracted from the isolated EVs. The miRNAs relative expression was analyzed and compared. Results In silico analysis identified miR-320b and miR-10b-5p as potential biomarkers for diagnosing NSCLC in smokers. Experimental analysis revealed differential expression of EVs-associated miRNAs in NSCLC patients with smoking and non-smoking histories. EVs-associated miR-10b-5p was significantly overexpressed in smoker NSCLC patients (p = 0.000), while miR-320b expression was significantly lower in this group (p = 0.018). Additionally, smoking intensity influenced miRNA expression, with higher smoking intensity correlating with increased miR-10b-5p expression and decreased miR-320b expression. ROC analysis demonstrated that EVs were a superior source of miRNAs compared to plasma for NSCLC diagnostics. miR-10b-5p and miR-320b in EVs showed higher diagnostic performance (AUC 0.878; 0.739) compared to plasma (AUC 0.628; 0.559). Conclusion CS exposure induces different expression of miR-10b-5p and miR-320b in EVs of NSCLC patients with smoking history. EV-related miR-10b-5p and miR-320b showed potential to be utilized as prognostic biomarker for smokers NSCLC patients.

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Extracellular vesicles (EVs) have emerged as promising therapeutics with broad clinical applications as diagnostic biomarkers and therapeutic drug delivery systems. Yet, these biopharmaceuticals pose a challenge in terms of manufacturing due to their complexity and heterogeneity. Despite advancements in the field, current purification technologies lack scalability and/or selectivity. Affinity chromatography (AC) − coupling unmatched specificity and scalability − could be used to simplify purification processing and generate clinical-grade EVs with higher titers and purity. In the present work, we report the implementation of an immuno-AC resin to capture and purify EVs directly from clarified cellular feedstocks. Firstly, to guide and support marker selection, vesicle phenotype characterization was conducted using single particle interferometric reflectance image sensing (SP-IRIS) coupled with immunofluorescence. CD81 was the marker which shown to be more present and more likely to have the other markers (CD63 and CD9). Thus, anti-CD81 VHH ligand was generated and evaluated towards recombinant CD81 protein and CD81 bearing EV particles using surface plasmon resonance (SPR). Different chromatographic studies with Anti-CD81 ligand immobilized onto agarose beads resin were conducted to optimize the process parameters (residence time, dynamic binding capacity and impurity clearance). At residence time of 2 min, on average 40 % of pure triple tetraspanin-positive EV fraction was recovered. The enrichment in EV particles herein obtained, based on scale-up calculations, it would be possible to produce 1 × 1013 EVs from a 1L cell culture, while meeting impurity requirements in a single-step purification process (impurity removal over 2 log reduction value). A single-step purification process is possible, enabling the successful isolation of homogeneous EVs population, counting with a final HCP titer of 60 ng/mL and 9 ng/mL of dsDNA impurities. EV’s morphological integrity and internalization ability were also demonstrated, showcasing elution’s efficiency under mild conditions. Overall, this work contributes to the development of a novel, highly specific, AC technology using a camelid-derived affinity ligand which, bridging the scalability requirements demanded of large-scale production, could potentiate the advent of EV-based therapies.

2025

Extracellular vesicles (EVs) have emerged as promising therapeutics with broad clinical applications as diagnostic biomarkers and therapeutic drug delivery systems. Yet, these biopharmaceuticals pose a challenge in terms of manufacturing due to their complexity and heterogeneity. Despite advancements in the field, current purification technologies lack scalability and/or selectivity. Affinity chromatography (AC) − coupling unmatched specificity and scalability − could be used to simplify purification processing and generate clinical-grade EVs with higher titers and purity. In the present work, we report the implementation of an immuno-AC resin to capture and purify EVs directly from clarified cellular feedstocks. Firstly, to guide and support marker selection, vesicle phenotype characterization was conducted using single particle interferometric reflectance image sensing (SP-IRIS) coupled with immunofluorescence. CD81 was the marker which shown to be more present and more likely to have the other markers (CD63 and CD9). Thus, anti-CD81 VHH ligand was generated and evaluated towards recombinant CD81 protein and CD81 bearing EV particles using surface plasmon resonance (SPR). Different chromatographic studies with Anti-CD81 ligand immobilized onto agarose beads resin were conducted to optimize the process parameters (residence time, dynamic binding capacity and impurity clearance). At residence time of 2 min, on average 40 % of pure triple tetraspanin-positive EV fraction was recovered. The enrichment in EV particles herein obtained, based on scale-up calculations, it would be possible to produce 1 × 1013 EVs from a 1L cell culture, while meeting impurity requirements in a single-step purification process (impurity removal over 2 log reduction value). A single-step purification process is possible, enabling the successful isolation of homogeneous EVs population, counting with a final HCP titer of 60 ng/mL and 9 ng/mL of dsDNA impurities. EV’s morphological integrity and internalization ability were also demonstrated, showcasing elution’s efficiency under mild conditions. Overall, this work contributes to the development of a novel, highly specific, AC technology using a camelid-derived affinity ligand which, bridging the scalability requirements demanded of large-scale production, could potentiate the advent of EV-based therapies.

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