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1.
BMC Cancer ; 24(1): 482, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627648

RESUMEN

BACKGROUND: Therapies for metastatic castration-resistant prostate cancer (mCRPC) include targeting the androgen receptor (AR) with androgen receptor inhibitors (ARIs) and prostate-specific membrane antigen (PSMA). Having the ability to detect AR, AR splice variant 7 (AR-V7), or PSMA in circulating tumor cells (CTCs) or circulating exosomal cell-free RNA (cfRNA) could be helpful to guide selection of the appropriate therapy for each individual patient. The Vortex Biosciences VTX-1 system is a label-free CTC isolation system that enables the detection of the expression of multiple genes in both CTCs and exosomal cfRNA from the same blood sample in patients with mCRPC. Detection of both AR-V7 and PSMA gene expression in both CTCs and cfRNA simultaneously has not yet been reported. METHODS: To characterize the combined VTX-1-AdnaDetect workflow, 22Rv1 cancer cells were spiked into blood from healthy donors and processed with the VTX-1 to mimic patient samples and assess performances (capture efficiency, purity, AR and AR-V7 expression). Then, we collected 19 blood samples from 16 patients with mCRPC and therapeutic resistance to androgen receptor inhibitors (ARIs). Plasma was separated and the plasma-depleted blood was processed further with the VTX-1 to collect CTCs. Both plasma exosomal cfRNA and CTCs were subsequently analyzed for AR, AR-V7, PSMA, and prostate-specific antigen (PSA) mRNA expression using the AdnaTest ProstateCancerPanel AR-V7 assay. RESULTS: AR-V7 expression could be detected in 22Rv1 cells spiked into blood from healthy volunteers as well as in CTCs and plasma-derived exosomal cfRNA from patients with mCRPC by processing blood with the VTX-1 CTC isolation system followed by the AdnaTest ProstateCancerPanel AR-V7 assay. 94.7% of patient blood samples (18/19) had detectable AR expression in either CTCs or exosomal cfRNA (16 in CTCs, 12 in cfRNA). 15.8% of the 19 patient blood samples (3/19) were found to have AR-V7-positive (AR-V7+) CTCs, one of which was also AR-V7+ in the exosomal cfRNA analysis. 42.1% of patient blood samples (8/19) were found to be PSMA positive (PSMA+): 26.3% (5/19) were PSMA+ in the CTC analysis and 31.6% (6/19) were PSMA+ in the exosomal cfRNA analysis. Of those 8 PSMA+ samples, 2 had detectable PSMA only in CTCs, and 3 had detectable PSMA only in exosomal cfRNA. CONCLUSION: VTX-1 enables isolation of CTCs and plasma exosomes from a single blood draw and can be used for detecting AR-V7 and PSMA mRNA in both CTCs and cfRNA in patients with mCRPC and resistance to ARIs. This technology facilitates combining RNA measurements in CTCs and exosomal cfRNA for future studies to develop potentially clinically relevant cancer biomarker detection in blood.


Asunto(s)
Ácidos Nucleicos Libres de Células , Exosomas , Células Neoplásicas Circulantes , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Antagonistas de Receptores Androgénicos/farmacología , Antagonistas de Receptores Androgénicos/uso terapéutico , Biomarcadores de Tumor/genética , Ácidos Nucleicos Libres de Células/genética , Ácidos Nucleicos Libres de Células/metabolismo , Exosomas/genética , Exosomas/metabolismo , Células Neoplásicas Circulantes/patología , Próstata/patología , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Isoformas de Proteínas/genética , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , ARN Mensajero/genética
2.
Front Oncol ; 10: 572895, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33117705

RESUMEN

Lung cancer is the leading cause of cancer-related mortality worldwide. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapies, based on the evaluation of EGFR mutations, have shown dramatic clinical benefits. EGFR mutation assays are mainly performed on tumor biopsies, which carry risks, are not always successful and give results relevant to the timepoint of the assay. To detect secondary EGFR mutations, which cause resistance to 1st and 2nd generation TKIs and lead to the administration of a 3rd generation drug, effective and non-invasive monitoring of EGFR mutation status is needed. Liquid biopsy analytes, such as circulating tumor cells (CTCs) and circulating tumor DNA (cfDNA), allow such monitoring over the course of the therapy. The aim of this study was to develop and optimize a workflow for the evaluation of cfDNA and CTCs in NSCLC patients all from one blood sample. Using Vortex technology and EntroGen ctEGFR assay, EGFR mutations were identified at 0.5 ng of DNA (∼83 cells), with a sensitivity ranging from 0.1 to 2.0% for a total DNA varying from 25 ng (∼4 CTCs among 4000 white blood cells, WBCs) to 1 ng (∼4 CTCs among 200 WBCs). The processing of plasma-depleted-blood provided comparable capture recovery as whole blood, confirming the possibility of a multimodality liquid biopsy analysis (cfDNA and CTC DNA) from a single tube of blood. Different anticoagulants were evaluated and compared in terms of respective performance. Blood samples from 24 NSCLC patients and 6 age-matched healthy donors were analyzed with this combined workflow to minimize blood volume needed and sample-to-sample bias, and the EGFR mutation profile detected from CTCs and cfDNA was compared to matched tumor tissues. Despite the limited size of the patient cohort, results from this non-invasive EGFR mutation analysis are encouraging and this combined workflow represents a valuable means for informing therapy selection and for monitoring treatment of patients with NSCLC.

3.
Cytometry A ; 93(12): 1240-1245, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30211979

RESUMEN

Clinicians continue to rely on invasive tissue biopsies as a mean to assess a patient's disease and prescribe appropriate treatment regimens. Biopsies not only are risky and expensive but also limit the understanding of disease. Circulating tumor cells (CTCs) can be isolated from a simple blood draw and offer a promising potential to both diagnose and monitor cancer progression. The VTX-1 Liquid Biopsy System automates the isolation of clinically relevant CTC populations, while simplifying their collection for easy analysis, ultimately expanding the clinical possibilities for CTCs. We present here the key features and performance of this automated system for isolating CTCs directly from whole blood, both with cell spiking experiments and patient samples. As a first step toward the characterization of CTCs for research applications and transfer to clinical practice, we present workflows for both molecular analyses and automated cell enumeration and biomarker quantification with the BioView imaging platform. © 2018 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.


Asunto(s)
Biopsia Líquida/métodos , Neoplasias/patología , Células Neoplásicas Circulantes/patología , Automatización de Laboratorios/métodos , Recuento de Células/métodos , Línea Celular Tumoral , Separación Celular/métodos , Humanos , Coloración y Etiquetado/métodos
4.
SLAS Technol ; 23(1): 16-29, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29355087

RESUMEN

Tumor tissue biopsies are invasive, costly, and collect a limited cell population not completely reflective of patient cancer cell diversity. Circulating tumor cells (CTCs) can be isolated from a simple blood draw and may be representative of the diverse biology from multiple tumor sites. The VTX-1 Liquid Biopsy System was designed to automate the isolation of clinically relevant CTC populations, making the CTCs available for easy analysis. We present here the transition from a cutting-edge microfluidic innovation in the lab to a commercial, automated system for isolating CTCs directly from whole blood. As the technology evolved into a commercial system, flexible polydimethylsiloxane microfluidic chips were replaced by rigid poly(methyl methacrylate) chips for a 2.2-fold increase in cell recovery. Automating the fluidic processing with the VTX-1 further improved cancer cell recovery by nearly 1.4-fold, with a 2.8-fold decrease in contaminating white blood cells and overall improved reproducibility. Two isolation protocols were optimized that favor either the cancer cell recovery (up to 71.6% recovery) or sample purity (≤100 white blood cells/mL). The VTX-1's performance was further tested with three different spiked breast or lung cancer cell lines, with 69.0% to 79.5% cell recovery. Finally, several cancer research applications are presented using the commercial VTX-1 system.


Asunto(s)
Automatización de Laboratorios/métodos , Células Sanguíneas , Separación Celular/métodos , Biopsia Líquida/métodos , Microfluídica/métodos , Células Neoplásicas Circulantes , Automatización de Laboratorios/instrumentación , Separación Celular/instrumentación , Humanos , Biopsia Líquida/instrumentación , Microfluídica/instrumentación , Reproducibilidad de los Resultados
5.
J Strength Cond Res ; 21(1): 48-51, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17313258

RESUMEN

Aerobic capacity and body composition were measured at 3 time points over a 1-year period in 26 Division 1A women soccer players from Texas A&M University, in order to determine whether there were seasonal changes in these parameters. Subjects were tested in December, immediately following a 4-month competitive season; in April, following 15 weeks of strength and conditioning; and immediately prior to the start of the regular season in August, following a 12-week summer strength and conditioning program. A periodized strength and conditioning program design was incorporated in order to optimize anaerobic and oxidative capacity immediately prior to the regular competitive season. Significant differences in VO2max were measured between August (49.24 +/- 4.38 ml x kg(-1) x min(-1)) and December (44.87 +/- 4.61 ml x kg(-1) x min(-1)). No significant changes in aerobic capacity were found between April (47.43 +/- 4.01 ml x kg(-1) x min(-1)) and August (49.64 +/- 5.25 ml x kg(-1) x min(-1)). Significant increases in body fat were measured between August (15.71 +/- 2.92%) and December (18.78 +/- 2.79%), before and after the competitive season, respectively. No significant changes in body fat were found between April (16.24 +/- 2.95%) and August (15.71 +/- 2.92%). The results of this study suggest that decreases in muscle mass over the course of a regular competitive season contribute to decreases in aerobic capacity in collegiate women soccer players. Although it is unknown whether this decrease in muscle mass is the result of inadequate training or a normal adaptation to the physiological demands imposed by soccer, the results of the current study suggest that resistance training volume should be maintained during the competitive season, in order to maintain preseason levels of muscle mass.


Asunto(s)
Consumo de Oxígeno/fisiología , Educación y Entrenamiento Físico/métodos , Estaciones del Año , Fútbol/fisiología , Adolescente , Adulto , Composición Corporal , Femenino , Humanos
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