Biopsia líquida y cáncer de próstata. Evidencia actual aplicada a la clínica / Liquid biopsy and prostate cancer. Current evidence applied to clinical practice

CONTEXTO: A pesar de ser una demostrada fuente de biomarcadores, la biopsia líquida aún no ha conseguido dar el paso a la práctica clínica habitual en pacientes con cáncer de próstata. Pocos biomarcadores se someten a una adecuada validación, prospectiva e independiente, de su valor predictivo o pronóstico y ello resulta en una falta de resultados con capacidad de traslación real a la clínica de los diferentes test disponibles. OBJETIVO: Realizar una síntesis, clínicamente pragmática, de la evidencia científica actual sobre la biopsia líquida sanguínea en cáncer de próstata. Adquisición de la evidencia: Revisión no sistemática de la literatura, acotando la búsqueda a trabajos sobre biopsia líquida de origen sanguíneo en cáncer de próstata. Se seleccionaron preferentemente aquellos trabajos en los cuales se estudian end-points clínicos aplicados al cáncer de próstata. Síntesis de la evidencia: Las formas de biopsia líquida más avanzadas en términos clínicos son las células tumorales circulantes (CTC) y el ADN tumoral circulante (ADNtc). Tanto CTC como ADNtc han demostrado su valor pronóstico en enfermedad metastásica. La determinación de ARV7 constituye el primer biomarcador predictivo de la enfermedad. Su traslación a la práctica clínica habitual pasa por la estandarización metodológica y la adecuada validación clínica de las distintas formas de detección disponibles. La detección de CTC en estadios iniciales de la enfermedad depende aún de la optimización de los métodos de detección y del desarrollo de la caracterización biológica de estas células. La información biológica aportada por CTC y ADNtc es distinta; por ello, el estudio de su adecuada conjunción es objeto de la investigación más actual. CONCLUSIONES: La ausencia de protocolos y estándares metodológicos es el factor limitante para llegar a conclusiones de impacto clínico. Por ello, el consenso y la unificación de criterios constituyen el verdadero desafío a corto plazo para la biopsia líquida

CONTEXT: Despite being a validated source of biomarkers, liquid biopsy has not yet succeeded in becoming part of the standard clinical practice in prostate cancer PATIENTS: Few biomarkers undergo adequate validation, prospective and independent, of their predictive and/or prognostic value, which results in a lack of the different available tests in the clinical practice. OBJECTIVE: To carry out a pragmatic synthesis of current scientific evidence on liquid biopsy for prostate cancer PATIENTS: Evidence acquisition: Non-systematic literature review, narrowing the search to papers on liquid biopsy from blood samples in prostate cancer PATIENTS: We mainly selected works evaluating clinical endpoints in prostate cancer. Evidence synthesis: The most clinically advanced forms of liquid biopsy are circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA). Both CTCs and ctDNA have demonstrated their prognostic value in metastatic disease. ARV7 determination is the first predictive biomarker of the disease. Its implementation into routine clinical practice requires methodological standardization and adequate clinical validation of the different available ways to detect it. The detection of CTCs in the early stages of the disease still depends on the optimization of the diagnostic methods and on the development of the biological characterization of these cells. The biological information provided by CTCs and ctDNA is different; therefore, the study of its adequate combination is the object of cutting-edge research. CONCLUSIONS: The absence of protocols and methodological standards is the limiting factor when aiming to reach conclusions that could have a potential impact on clinical practice. Therefore, the real short-term challenge for liquid biopsy is the establishment of consensus and common criterio

Impact of oxidative stress SNPs and dietary antioxidant quality score on prostate cancer.

Purpose: To analyse the relation between antioxidant genotypes and Dietary Antioxidant Quality score (DAQs) effect on prostate cancer (PCa) risk and aggressiveness in a Spanish population.Methods: Men (N = 155 patients and 152 controls) with PSA values >4 ng/ml were enrolled in the project. DAQs were used considering the daily recommended intake for Spanish people (DRI). Genotyping of 5 SNPs rs662 (PON1), rs10432782 (SOD1), rs4880 (SOD2), rs17650792 (GPX1) and rs1001179 (CAT) were included for the analysis.Results: rs17650792 was statistically significant between case and controls subjects. When comparing D´Amico risk, we found that rs662 (CC), rs10432782 (G allele) and rs17650792 (GG) confer a protection. When testing SNP-antioxidant nutrients interactions, we found an intake of vitamin A and rs100179 (T carriers) and selenium and rs17650792 (G carriers) confers a protection of being in low risk classification.Conclusions: We reported by the first time a correlation between rs662 (PON1) and PCa aggressiveness.

Liquid biopsy and prostate cancer. Current evidence applied to clinical practice. / Biopsia líquida y cáncer de próstata. Evidencia actual aplicada a la clínica.

CONTEXT: Despite being a validated source of biomarkers, liquid biopsy has not yet succeeded in becoming part of the standard clinical practice in prostate cancer patients. Few biomarkers undergo adequate validation, prospective and independent, of their predictive and/or prognostic value, which results in a lack of the different available tests in the clinical practice. OBJECTIVE: To carry out a pragmatic synthesis of current scientific evidence on liquid biopsy for prostate cancer patients. EVIDENCE ACQUISITION: Non-systematic literature review, narrowing the search to papers on liquid biopsy from blood samples in prostate cancer patients. We mainly selected works evaluating clinical endpoints in prostate cancer. EVIDENCE SYNTHESIS: The most clinically advanced forms of liquid biopsy are circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA). Both CTCs and ctDNA have demonstrated their prognostic value in metastatic disease. ARV7 determination is the first predictive biomarker of the disease. Its implementation into routine clinical practice requires methodological standardization and adequate clinical validation of the different available ways to detect it. The detection of CTCs in the early stages of the disease still depends on the optimization of the diagnostic methods and on the development of the biological characterization of these cells. The biological information provided by CTCs and ctDNA is different; therefore, the study of its adequate combination is the object of cutting-edge research. CONCLUSIONS: The absence of protocols and methodological standards is the limiting factor when aiming to reach conclusions that could have a potential impact on clinical practice. Therefore, the real short-term challenge for liquid biopsy is the establishment of consensus and common criteria.

The role of miRNAs as biomarkers in prostate cancer.

There is an urged need of non-invasive biomarkers for the implementation of precision medicine. These biomarkers are required to these days for improving prostate cancer (PCa) screening, treatment or stratification in current clinical strategies. There are several commercial kits (Oncotype DX genomic prostate score®, Prolaris®, among others) that use genomic changes, rearrangement or even non-coding RNA events. However, none of them are currently used in the routine clinical practice. Many recent studies indicate that miRNAs are relevant molecules (small single-stranded non-coding RNAs that regulate gene expression of more than 30% of human genes) to be implement non-invasive biomarkers. However, contrasting to others tumors, such as breast cancer where miR-21 seems to be consistently upregulated; PCa data are controversial. Here we reported an extended revision about the role of miRNAs in PCa including data of AR signaling, cell cycle, EMT process, CSCs regulation and even the role of miRNAs as PCa diagnostic, prognostic and predictive tool. It is known that current biomedical research uses big-data analysis like Next Generation Sequencing (NGS) analysis. We also conducted an extensive online search, including the main platforms and kits for miRNAs massive analysis (like MiSeq, Nextseq 550, or Ion S5™ systems) indicating their pros, cons and including pre-analytical and analytical issues of miRNA studies.

Genetic markers a landscape in prostate cancer.

Prostate cancer (PC) is one of the most common cancers worldwide. The observed variability in progression and responses to the same treatment between patients underlie the genetic heterogeneity of the disease. Nowadays, screening and follow-up biomarkers in PC are still having a deep lack of information, which makes difficult the cancer diagnosis, prognosis and the selection of the most suitable therapies. This is making that currently unnecessary biopsies, over-treatments and hormonoresistances have high rates of prevalence among patients. New biomarkers are urgently needed and in this sense genomic biomarkers could be the most suitable tools. These genetic markers will be helpful for improving the precision of prognostic and the predictive current tools which are employed in the clinical practice. A recent literature search up was conducted, including clinical trials and pre-clinical basic research studies. Keywords included germline variants, prostate cancer, biomarkers, androgen deprivation therapy, screening and liquid biopsy; among others. We have reviewed how germline variants, CNVs and repetitive regions are relevant to prostate carcinogenesis, treatment and progression. Moreover, we have also considered novel biomarkers for PC prognosis based on differentially expressed genes. Finally, we have included new strategies in recent markers of liquid biopsy or updated technologies for minimal samples analysis. The improvement of genetic markers use and their application to the clinical practice, will enhance the variability of simple, non-invasive, tools such as liquid biopsy and germline variants, these will reduce the number of PC needle biopsies and current over-treatments that are usual in the management of this cancer.

Circulating Tumor Cells: Markers and Methodologies for Enrichment and Detection.

Cancer is a leading cause of disease worldwide; however, nowadays many points of its initiation processes are unknown. In this chapter, we are focusing on the role of liquid biopsies in cancer detection and progression. CTCs are one of the main components of liquid biopsies, they represent a subset of tumor cells that have acquired the ability to disseminate from the primary tumor and intravasate to the circulatory system. The greatest challenge in the detection of CTCs is their rarity in the blood. Human blood consists of white blood cells (5-10 × 106/mL), red blood cells (5-9 × 109/mL), and platelets (2.5-4 × 108/mL); very few CTCs will be present even in patients with known metastatic disease, with often less than one CTC per mL of blood. CTCs are found in frequencies on the order of 1-10 CTCs per mL of whole blood in patients with metastatic disease, and it is reduced in half for non-metastatic stages. Therefore, accurate methodologies for their capture and analysis are really important. The main aim of the present chapter is to describe different methodologies for CTCs capturing and analysis.

Somatic Mutations in Prostate Cancer: Closer to Personalized Medicine.

The molecular cause of prostate cancer (PCa) is still unclear; however, its progression involves androgen, PI3K/Akt, and PTEN signaling, as cycle and apoptotic pathways. Alterations in oncogenes and tumor suppressor genes as PIK3CA, BRAF, KRAS and TP53 are not very common. Recently, somatic mutations have been discovered in relation to cancer progression mainly in genes such as PIK3CA; however, little data has been described in PCa. Nowadays genetic tools allow us to investigate multiple details about the biological heterogeneity of PCa, to better understand the mechanisms of disease progression and treatment resistance. Therefore, if the most relevant somatic mutations were included during screening, we could identify the best treatment for the right patient, bringing us closer to personalized medicine. The main objective of this article is to provide a review of the principal somatic mutations that appear to have a relevant role in hormonal cancers, like prostate cancer.