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2.
Adv Biol (Weinh) ; 8(1): e2300233, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670402

RESUMO

Extracellular vesicles (EVs) are highly sought after as a source of biomarkers for disease detection and monitoring. Tumor EV isolation, processing, and evaluation from biofluids is convoluted by EV heterogeneity and biological contaminants and is limited by technical processing efficacy. This study rigorously compares common bulk EV isolation workflows (size exclusion chromatography, SEC; membrane affinity, MA) alongside downstream RNA extraction protocols to investigate molecular analyte recovery. EV integrity and recovery is evaluated using a variety of technologies to quantify total intact EVs, total and surface proteins, and RNA purity and recovery. A comprehensive evaluation of each analyte is performed, with a specific emphasis on maintaining user (n = 2), biological (n = 3), and technical replicates (n≥3) under in vitro conditions. Subsequent study of tumor EV spike-in into healthy donor plasma samples is performed to further validate biofluid-derived EV purity and isolation for clinical application. Results show that EV surface integrity is considerably preserved in eluates from SEC-derived EVs, but RNA recovery and purity, as well as bulk protein isolation, is significantly improved in MA-isolated EVs. This study concludes that EV isolation and RNA extraction pipelines govern recovered analyte integrity, necessitating careful selection of processing modality to enhance recovery of the analyte of interest.


Assuntos
Vesículas Extracelulares , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/metabolismo , Vesículas Extracelulares/química , Vesículas Extracelulares/metabolismo , Cromatografia em Gel , RNA/análise , RNA/metabolismo , Proteínas de Membrana/análise , Proteínas de Membrana/metabolismo
3.
Nat Commun ; 15(1): 7074, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152110

RESUMO

Glioma represents the most common central nervous system neoplasm in adults. Current classification scheme utilizes molecular alterations, particularly IDH1.R132H, to stratify lesions into distinct prognostic groups. Identification of the single nucleotide variant through traditional tissue biopsy assessment poses procedural risks and does not fully reflect the heterogeneous and evolving tumor landscape. Here, we introduce a liquid biopsy assay, mt-IDH1dx. The blood-based test allows minimally invasive detection of tumor-derived extracellular vesicle RNA using only 2 ml plasma volume. We perform rigorous, blinded validation testing across the study population (n = 133), comprising of IDH1.R132H patients (n = 80), IDH1 wild-type gliomas (n = 44), and age matched healthy controls (n = 9). Results from our plasma testing demonstrate an overall sensitivity of 75.0% (95% CI: 64.1%-84.0%), specificity 88.7% (95% CI: 77.0%-95.7%), positive predictive value 90.9%, and negative predictive value 70.1% compared to the tissue gold standard. In addition to fundamental diagnostic applications, the study also highlights the utility of mt-IDH1dx platform for blood-based monitoring and surveillance, offering valuable prognostic information. Finally, the optimized workflow enables rapid and efficient completion of both tumor tissue and plasma testing in under 4 hours from the time of sampling.


Assuntos
Neoplasias Encefálicas , Glioma , Isocitrato Desidrogenase , Mutação , Humanos , Isocitrato Desidrogenase/genética , Glioma/genética , Glioma/sangue , Glioma/diagnóstico , Glioma/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Biópsia Líquida/métodos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/diagnóstico , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Sensibilidade e Especificidade , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Estudos de Casos e Controles
4.
Cancers (Basel) ; 15(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37568734

RESUMO

Over the last 20 years, gliomas have made up over 89% of malignant CNS tumor cases in the American population (NIH SEER). Within this, glioblastoma is the most common subtype, comprising 57% of all glioma cases. Being highly aggressive, this deadly disease is known for its high genetic and phenotypic heterogeneity, rendering a complicated disease course. The current standard of care consists of maximally safe tumor resection concurrent with chemoradiotherapy. However, despite advances in technology and therapeutic modalities, rates of disease recurrence are still high and survivability remains low. Given the delicate nature of the tumor location, remaining margins following resection often initiate disease recurrence. Photodynamic therapy (PDT) is a therapeutic modality that, following the administration of a non-toxic photosensitizer, induces tumor-specific anti-cancer effects after localized, wavelength-specific illumination. Its effect against malignant glioma has been studied extensively over the last 30 years, in pre-clinical and clinical trials. Here, we provide a comprehensive review of the three generations of photosensitizers alongside their mechanisms of action, limitations, and future directions.

5.
Cell Rep Med ; 4(10): 101196, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37725979

RESUMO

Liquid biopsy, through isolation and analysis of disease-specific analytes, has evolved as a promising tool for safe and minimally invasive diagnosis and monitoring of tumors. It also has tremendous utility as a companion diagnostic allowing detection of biomarkers in a range of cancers (lung, breast, colon, ovarian, brain). However, clinical implementation and validation remains a challenge. Among other stages of development, preanalytical variables are critical in influencing the downstream cellular and molecular analysis of different analytes. Although considerable progress has been made to address these challenges, a comprehensive assessment of the impact on diagnostic parameters and consensus on standardized and optimized protocols is still lacking. Here, we summarize and critically evaluate key variables in the preanalytical stage, including study population selection, choice of biofluid, sample handling and collection, processing, and storage. There is an unmet need to develop and implement comprehensive preanalytical guidelines on the optimal practices and methodologies.


Assuntos
Neoplasias , Humanos , Neoplasias/diagnóstico , Biópsia Líquida , Biomarcadores
6.
Cell Rep Med ; 4(10): 101198, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37716353

RESUMO

The emerging field of liquid biopsy stands at the forefront of novel diagnostic strategies for cancer and other diseases. Liquid biopsy allows minimally invasive molecular characterization of cancers for diagnosis, patient stratification to therapy, and longitudinal monitoring. Liquid biopsy strategies include detection and monitoring of circulating tumor cells, cell-free DNA, and extracellular vesicles. In this review, we address the current understanding and the role of existing liquid-biopsy-based modalities in cancer diagnostics and monitoring. We specifically focus on the technical and clinical challenges associated with liquid biopsy and biomarker development being addressed by the Liquid Biopsy Consortium, established through the National Cancer Institute. The Liquid Biopsy Consortium has developed new methods/assays and validated existing methods/technologies to capture and characterize tumor-derived circulating cargo, as well as addressed existing challenges and provided recommendations for advancing biomarker assays.


Assuntos
Ácidos Nucleicos Livres , Vesículas Extracelulares , Células Neoplásicas Circulantes , Humanos , Biópsia Líquida , Ácidos Nucleicos Livres/genética , Biomarcadores , Células Neoplásicas Circulantes/patologia
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