Search

BACKGROUND: Plasma cell-free DNA (cfDNA) is derived from cellular death in various tissues. Investigating the tissue origin of cfDNA through cell type deconvolution, we can detect changes in tissue homeostasis that occur during disease progression or in response to treatment. Consequently, cfDNA has emerged as a valuable noninvasive biomarker for disease detection and treatment monitoring. Although there are many methylation-based methods for cfDNA cell type deconvolution, a comprehensive and systematic evaluation of these methods has yet to be conducted. RESULTS: In this study, we benchmark five methods: MethAtlas, cfNOMe toolkit, CelFiE, CelFEER, and UXM. Utilizing deep whole-genome bisulfite sequencing data from 35 human cell types, we generate in silico cfDNA samples with ground truth cell type proportions to assess the deconvolution performance of the five methods under multiple scenarios. Our findings indicate that multiple factors, including reference marker selection, sequencing depth, and reference atlas completeness, jointly influence the deconvolution performance. Notably, an incomplete reference with missing markers or cell types leads to suboptimal results. We observe performance differences among methods under varying conditions, underscoring the importance of tailoring cfDNA deconvolution analyses. To increase the clinical relevance of our findings, we further evaluate each methods performance in potential clinical applications using real-world datasets. CONCLUSIONS: Based on the benchmark results, we propose general guidelines to choose the suitable methods based on sequencing depth of the cfDNA data and completeness of the reference atlas to maximize the performance of methylation-based cfDNA cell type deconvolution.

Non-invasive prenatal testing (NIPT) employs ultra-low-pass sequencing of maternal plasma cell-free DNA to detect fetal trisomy. Its global adoption has established NIPT as a large human genetic resource for exploring genetic variations and their associations with phenotypes. Here, we present methods for analyzing large-scale, low-depth NIPT data, including customized algorithms and software for genetic variant detection, genotype imputation, family relatedness, population structure inference, and genome-wide association analysis of maternal genomes. Our results demonstrate accurate allele frequency estimation and high genotype imputation accuracy (R2>0.84) for NIPT sequencing depths from 0.1× to 0.3×. We also achieve effective classification of duplicates and first-degree relatives, along with robust principal-component analysis. Additionally, we obtain an R2>0.81 for estimating genetic effect sizes across genotyping and sequencing platforms with adequate sample sizes. These methods offer a robust theoretical and practical foundation for utilizing NIPT data in medical genetic research.

Hemangiosarcoma is a highly malignant tumor commonly affecting canines, originating from endothelial cells that line blood vessels, underscoring the importance of early detection. This canine cancer is analogous to human angiosarcoma, and the development of liquid biopsies leveraging cell-free DNA (cfDNA) represents a promising step forward in early cancer diagnosis. In this study, we utilized Whole Genome Sequencing (WGS) to analyze fragment sizes and copy number alterations (CNAs) in cfDNA from 21 hemangiosarcoma-affected and 36 healthy dogs, aiming to enhance early cancer detection accuracy through machine learning models. Our findings reveal that similar to trends in human oncology, hemangiosarcoma samples exhibited shorter DNA fragment sizes compared to healthy controls, with a notable leftward shift in the primary peak. Interestingly, canine hemangiosarcoma DNA fragment sizes demonstrated eight distinct periodic patterns diverging from those typically observed in human angiosarcoma. Additionally, we identified seven novel genomic gains and nine losses in the hemangiosarcoma samples. Applying machine learning to the cfDNA fragment size distribution, we achieved an impressive average Area Under the Curve (AUC) of 0.93 in 10-fold cross-validation, underscoring the potential of this approach for precise early-stage cancer classification. This study confirms distinctive cfDNA fragment size and CNA patterns in hemangiosarcoma-affected vs. healthy dogs and demonstrates the promise of these biomarkers in canine cancer screening, early detection, and monitoring via liquid biopsies. These findings establish a foundation for broader research on cfDNA analysis in various canine cancers, integrating methodologies from human oncology to enhance early detection and diagnostic precision in veterinary medicine. [ABSTRACT FROM AUTHOR]

The management of early-stage colon cancer involves surgical resection of the primary tumor with or without chemotherapy, depending on pathological staging. The benefit of adjuvant chemotherapy for stage II and III colon cancer is approximately 5% and 15%, indicating the need for optimization for risk stratification and patient selection. Several studies have revealed that current clinicopathological factors lack precision. Circulating tumor DNA (ctDNA) is cell-free DNA originating from cancer cells and can be detected even in the absence of radiologically detectable disease among patients with colon cancer. Recent cohort studies revealed that ctDNA is one of the most significant prognostic factors for patients with early-stage colon cancer, surpassing pathological and clinical risk factors. Prospective cohort studies also suggest there may be a predictive role for ctDNA on the decision for consideration of adjuvant therapy. Currently, randomized clinical trials are enrolling to better define this role. In this review article, we review recent literature on ctDNA and its role in patients with colon cancer. We also elaborate on the future clinical utility of ctDNA in clinical practice and the unmet need for research to optimize currently available ctDNA assays. [ABSTRACT FROM AUTHOR]

Second Primary Cancers (SPCs) are defined as cancers that develop either simultaneously or metachronously in the same individual who has been diagnosed with and survived one primary cancer. SPCs exhibit a high incidence rate and represent the primary cause of mortality among survivors of first primary cancers. There is growing concern about the dangers of SPCs. This review summarizes recent studies on the mechanisms of SPCs, including the roles of genomic changes after first primary cancer (FPC) treatments, stromal cell phenotypic and metabolic changes, hormone levels and receptor expression, immunosuppression, aberrant gene methylation, EGFR signaling, and cell-free DNA in SPC development. This comprehensive analysis contributes to elucidating current research trends in SPC mechanisms and enhances our understanding of the underlying pathophysiology. Furthermore, potential applications of intratumoral microbes, single-cell multi-omics, and metabolomics in investigating SPC mechanisms are also discussed, providing new ideas for follow-up studies. [ABSTRACT FROM AUTHOR]

Background: Noninvasive prenatal testing (NIPT) is increasingly used to screen for fetal chromosomal aneuploidy by analyzing cell-free DNA (cfDNA) in peripheral maternal blood. The method provides an opportunity for early detection of large genetic abnormalities without an increased risk of miscarriage due to invasive procedures. Commercial applications for use at clinical laboratories often take advantage of DNA sequencing technologies and include the bioinformatic workup of the sequence data. The interpretation of the test results and the clinical report writing, however, remains the responsibility of the diagnostic laboratory. In order to facilitate this step, we developed NIPTviewer, a web-based application to visualize and guide the interpretation of NIPT data results. Results: NIPTviewer has a database functionality to store the NIPT results and a web interface for user interaction and visualization. The application has been implemented as part of a novel analysis pipeline for NIPT in a diagnostic laboratory at Uppsala University Hospital. The validation data set included 84 previously analyzed plasma samples with known results regarding chromosomes 13, 18, 21, X and Y. They were sequenced in six different experiments, uploaded to NIPTviewer and assigned to a clinical laboratory geneticist for interpretation. The results of all previously analyzed samples were replicated. Conclusion: NIPTviewer facilitates NIPT results interpretation and has been implemented as part of a NIPT analysis routine that was accredited by the national accreditation body for Sweden (Swedac). [ABSTRACT FROM AUTHOR]

Enzyme engineering is limited by the challenge of rapidly generating and using large datasets of sequence-function relationships for predictive design. To address this challenge, we develop a machine learning (ML)-guided platform that integrates cell-free DNA assembly, cell-free gene expression, and functional assays to rapidly map fitness landscapes across protein sequence space and optimize enzymes for multiple, distinct chemical reactions. We apply this platform to engineer amide synthetases by evaluating substrate preference for 1217 enzyme variants in 10,953 unique reactions. We use these data to build augmented ridge regression ML models for predicting amide synthetase variants capable of making 9 small molecule pharmaceuticals. Over these nine compounds, ML-predicted enzyme variants demonstrate 1.6- to 42-fold improved activity relative to the parent. Our ML-guided, cell-free framework promises to accelerate enzyme engineering by enabling iterative exploration of protein sequence space to build specialized biocatalysts in parallel. While machine learning shows promise in expanding protein engineering efforts, its potential is limited by the challenge of gathering large datasets of sequence-function relationships. Here, authors introduce a platform that integrates cell-free DNA assembly and gene expression to accelerate enzyme engineering. [ABSTRACT FROM AUTHOR]

The emergence of liquid biopsy technologies holds great promise in the cancer setting, including in pediatric central nervous system (CNS) tumors. In contrast to broad lower-depth sequencing, commonly referred to as low pass whole genome sequencing (WGS), targeted platforms with a higher depth of coverage have also been established. Here, we review targeted liquid biopsy techniques with applicability to pediatric CNS tumors. These include polymerase chain reaction (PCR), both droplet digital PCR and reverse transcription-based PCR, Sanger sequencing, and next-generation sequencing approaches that incorporate amplicon- and hybrid capture-based methods. The goal of this paper is to facilitate an understanding of these targeted techniques and provide a context for clinical relevance within disease categories, as well as a discussion on optimizing real-world implementation for pediatric CNS tumors. [ABSTRACT FROM AUTHOR]

The treatment landscape for advanced melanoma has transformed significantly with the advent of BRAF and MEK inhibitors (BRAF/MEKi) targeting BRAFV600 mutations, as well as immune checkpoint inhibitors (ICI) like anti-PD-1 monotherapy or its combinations with anti-CTLA-4 or anti-LAG-3. Despite that, many patients still do not benefit from these treatments at all or develop resistance mechanisms. Therefore, prognostic and predictive biomarkers are needed to identify patients who should switch or escalate their treatment strategies or initiate an intensive follow-up. In melanoma, liquid biopsy has shown promising results, with a potential role in predicting relapse in resected high-risk patients or in disease monitoring during the treatment of advanced disease. Several components in peripheral blood have been analyzed, such as circulating tumor cells (CTCs), cell-free DNA (cfDNA), and circulant tumoral DNA (ctDNA), which have turned out to be particularly promising. To analyze ctDNA in blood, different techniques have proven to be useful, including digital droplet polymerase chain reaction (ddPCR) to detect specific mutations and, more recently, next-generation sequencing (NGS) techniques, which allow analyzing a broader repertoire of the mutation landscape of each patient. In this review, our goal is to update the current understanding of liquid biopsy, focusing on the use of ctDNA as a biological material in the daily clinical management of melanoma patients, in particular those with advanced disease treated with ICI. [ABSTRACT FROM AUTHOR]

The progression of colorectal cancer is strongly influenced by environmental and genetic conditions. One of the key factors is tumor heterogeneity which is extensively studied by cfDNA and bulk sequencing methods; however, we lack knowledge regarding its effects at the single-cell level. Motivated by this, we aimed to employ an end-to-end single-cell sequencing workflow from tissue-derived sample isolation to exome sequencing. Our main goal was to investigate the heterogeneity patterns by laser microdissecting samples from different locations of a tissue slide. Moreover, by studying healthy colon control, tumor-associated normal, and colorectal cancer tissues, we explored tissue-specific heterogeneity motifs. For completeness, we also compared the performance of the whole-exome bulk, cfDNA, and single-cell sequencing methods based on variation at the level of a single nucleotide. [ABSTRACT FROM AUTHOR]

Non-invasive prenatal testing (NIPT) has been widely adopted for the screening of chromosomal abnormalities; however, its adoption for monogenic disorders, such as β-thalassaemia, has proven challenging. Haemoglobinopathies are the most common monogenic disorders globally, with β-thalassaemia being particularly prevalent in Cyprus. This study introduces a non-invasive prenatal haplotyping (NIPH) assay for β-thalassaemia, utilizing cell-free DNA (cfDNA) from maternal plasma. The assay determines paternal inheritance by analyzing highly heterozygous single-nucleotide variants (SNVs) in the β-globin gene cluster. To identify highly heterozygous SNVs in the population, 96 randomly selected samples were processed using Illumina DNA-prep NGS chemistry. A custom, high-density NGS genotyping panel, named HAPLONID, was designed with 169 SNVs, including 15 common pathogenic ones. The AmpliSeq for Illumina assay was then applied to cfDNA to evaluate the panel's efficiency in performing NIPT for β-thalassaemia. Analysis revealed 219 highly polymorphic SNVs, and the sequencing of 17 families confirmed successful paternal allele determination. The NIPH assay demonstrated 100% success in diagnostic interpretation. This study achieved the advancement of an integrated NGS-NIPT assay for β-thalassaemia, bringing it one step closer to being a diagnostic assay and thereby enabling a reduction in the number of risky invasive prenatal sampling procedures in Cyprus and elsewhere. [ABSTRACT FROM AUTHOR]

Purpose: Renal cell carcinoma (RCC) is a common malignancy, with patients frequently diagnosed at an advanced stage due to the absence of sufficiently sensitive detection technologies, significantly compromising patient survival and quality of life. Advances in cell-free DNA (cfDNA) methylation profiling using liquid biopsies offer a promising non-invasive diagnostic option, but robust biomarkers for early detection are current not available. This study aimed to identify methylation biomarkers for RCC and establish a DNA methylation signature-based prognostic model for this disease. Methods: High-throughput methylation sequencing was performed on peripheral blood samples obtained from 49 primarily Stage I RCC patients and 44 healthy controls. Comparative analysis and Least Absolute Shrinkage and Selection Operator (LASSO) regression methods were employed to identify RCC methylation signatures.Subsequently, methylation markers-based diagnostic and prognostic models for RCC were independently trained and validated using random forest and Cox regression methodologies, respectively. Results: Comparative analysis revealed 864 differentially methylated CpG islands (DMCGIs), 96.3% of which were hypermethylated. Using a training set from The Cancer Genome Atlas (TCGA) dataset of 443 early-stage RCC tumors and matched normal tissues, we applied LASSO regression and identified 23 methylation signatures. We then constructed a random forest-based diagnostic model for early-stage RCC and validated the model using two independent datasets: a TCGA set of 460 RCC tumors and controls, and a blood sample set from our study of 15 RCC cases and 29 healthy controls. For Stage I RCC tissue, the model showed excellent discrimination (AUC-ROC: 0.999, sensitivity: 98.5%, specificity: 100%). Blood sample validation also yielded commendable results (AUC-ROC: 0.852, sensitivity: 73.9%, specificity: 89.7%). Further analysis using Cox regression identified 7 of the 23 DMCGIs as prognostic markers for RCC, allowing the development of a prognostic model with strong predictive power for 1-, 3-, and 5-year survival (AUC-ROC > 0.7). Conclusions: Our findings highlight the critical role of hypermethylation in RCC etiology and progression, and present these identified biomarkers as promising candidates for diagnostic and prognostic applications. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) lacks a specific biomarker, but is defined by relatively selective toxicity to motor neurons (MN). As others have highlighted, this offers an opportunity to develop a sensitive and specific biomarker based on detection of DNA released from dying MN within accessible biofluids. Here we have performed whole genome bisulfite sequencing (WGBS) of iPSC-derived MN from neurologically normal individuals. By comparing MN methylation with an atlas of tissue methylation we have derived a MN-specific signature of hypomethylated genomic regions, which accords with genes important for MN function. Through simulation we have optimised the selection of regions for biomarker detection in plasma and CSF cell-free DNA (cfDNA). However, we show that MN-derived DNA is not detectable via WGBS in plasma cfDNA. In support of our experimental finding, we show theoretically that the relative sparsity of lower MN sets a limit on the proportion of plasma cfDNA derived from MN which is below the threshold for detection via WGBS. Our findings are important for the ongoing development of ALS biomarkers. The MN-specific hypomethylated genomic regions we have derived could be usefully combined with more sensitive detection methods and perhaps with study of CSF instead of plasma. Indeed we demonstrate that neuronal-derived DNA is detectable in CSF. Our work is relevant for all diseases featuring death of rare cell-types. [ABSTRACT FROM AUTHOR]

Introduction: Placental DNA methylation differences have been associated with timing in gestation and pregnancy complications. Maternal cell-free DNA (cfDNA) partly originates from the placenta and could enable the minimally invasive study of placental DNA methylation dynamics. We will for the first time longitudinally investigate cfDNA methylation during pregnancy by using Methylated DNA Sequencing (MeD-seq), which is compatible with low cfDNA levels and has an extensive genome-wide coverage. We aim to investigate DNA methylation in placental tissues and cfDNA during different trimesters in uncomplicated pregnancies, and in pregnancies with placental-related complications, including preeclampsia and fetal growth restriction. Identified gestational-age and disease-specific differentially methylated regions (DMRs) could lead to numerous applications including biomarker development. Methods and analysis: Our study design involves three sub-studies. Sub-study 1 is a single-centre prospective, observational subcohort embedded within the Rotterdam Periconception cohort (Predict study). We will longitudinally collect maternal plasma in each trimester and during delivery, and sample postpartum placentas (n = 300). In sub-study 2, we will prospectively collect first and second trimester placental tissues (n = 10 per trimester). In sub-study 3 we will retrospectively collect plasma after non-invasive prenatal testing (NIPT) in an independent validation case-control cohort (n = 30–60). A methylation-dependent restriction enzyme (LpnPI) will be used to generate DNA fragments followed by sequencing on the Illumina NextSeq2000 platform. DMRs will be identified in placental tissues and cell types, and in cfDNA related to gestational-age or placental-related complications. (Paired) placental methylation profiles will be correlated to DMRs in cfDNA to aid tissue-of-origin analysis. We will establish a methylation score to predict associated diseases. Discussion: This study will provide insights in placental DNA methylation dynamics in health and disease, and could lead to clinical relevant biomarkers. [ABSTRACT FROM AUTHOR]

Plasma cell‐free DNA (cfDNA) analysis to track estrogen receptor 1 (ESR1) mutations is highly beneficial for the identification of tumor molecular dynamics and the improvement of personalized treatments for patients with metastatic breast cancer (MBC). Plasma‐cfDNA is, up to now, the most frequent liquid biopsy analyte used to evaluate ESR1 mutational status. Circulating tumor cell (CTC) enumeration and molecular characterization analysis provides important clinical information in patients with MBC. In this study, we investigated whether analysis of CTCs and circulating tumor DNA (ctDNA) provide similar or complementary information for the analysis of ESR1 mutations. We analyzed both plasma‐cfDNA (n = 90) and paired CTC‐derived genomic DNA (gDNA; n = 42) from 90 MBC patients for seven ESR1 mutations. Eight out of 90 (8.9%) plasma‐cfDNA samples tested using the ddPLEX Mutation Detection Assay (Bio‐Rad, Hercules, CA, USA), were found positive for one ESR1 mutation, whereas 11/42 (26.2%) CTC‐derived gDNA samples were found positive for at least one ESR1 mutation. Direct comparison of paired samples (n = 42) revealed that the ESR1 mutation rate was higher in CTC‐derived gDNA (11/42, 26.2%) than in plasma‐cfDNA (6/42, 14.3%) samples. Our results, using this highly sensitive ddPLEX assay, reveal a higher percentage of mutations in CTC‐derived gDNAs than in paired ctDNA in patients with MBC. CTC‐derived gDNA analysis should be further evaluated as an important and complementary tool to ctDNA for identifying patients with ESR1 mutations and for guiding individualized therapy. [ABSTRACT FROM AUTHOR]

Background: Cell-free DNA (cfDNA) is present in healthy individuals but is elevated in those undergoing physical exertion, trauma, sepsis, and certain cancers. Maintaining cfDNA concentrations is vital for immune homeostasis and preventing inflammatory responses. Understanding cfDNA release and clearance is essential for using cfDNA as a biomarker in clinical diagnostics. We focused on the fragment size of cfDNA and investigated cfDNA dynamics and half-life, particularly the 100–250 base pair fragments. Methods: Healthy, adult men (n = 5; age 40 ± 4.1 years) were subjected to a 30 min treadmill exercise. Blood samples were collected at 0, 5, 10, 15, 30, and 60 min post-exercise using PAXgene® Blood ccfDNA tubes to stabilize and prevent nuclease-mediated cfDNA degradation and minimize genomic DNA contamination risk. The cfDNA concentration was measured using an electrophoresis-based technique (4150 TapeStation system) to quantify the concentration based on cfDNA fragment size. Results: The results showed a cfDNA half-life of 24.2 min, with a transient increase in 100–250 base pair cfDNA fragments post-exercise, likely due to nuclease activity. These levels rapidly reverted to the baseline within an hour. Conclusions: The rapid clearance of cfDNA underscores its potential as a biomarker for real-time disease monitoring and the evaluation of treatment efficacy. This study is expected to standardize cfDNA investigations, enhancing diagnosis and treatment monitoring across various disease conditions. [ABSTRACT FROM AUTHOR]

Background: Given the poor prognosis of metastatic pancreatic adenocarcinoma (mPDAC), closer disease monitoring through liquid biopsy, most frequently based on serial measurements of cell-free mutated KRAS (KRASmut cfDNA), has become a highly active research focus, aimed at improving patients' long-term outcomes. However, most of the available data show only a limited predictive and prognostic value of single-parameter-based methods. We hypothesized that a combined longitudinal analysis of KRASmut cfDNA and novel protein biomarkers could improve risk stratification and molecular monitoring of patients with mPDAC. Methods: We prospectively collected 160 plasma samples from 47 patients with mPDAC at our institution. Highly sensitive single-target ddPCR assays were employed to detect and quantify KRASmut cfDNA. Additionally, analysis of ten protein biomarkers was performed through Enzyme-linked Immunosorbent Assay (ELISA), and Carbohydrate-Antigen 19-9 (CA 19-9) dynamics were registered. Results: KRASmut cfDNA was detectable in 37/47 (78.7%) patients throughout the course of study, and CA 19-9 levels were elevated in 40 out of 47 (85.1%) patients. KRASmut cfDNA increase at the time of the first follow-up could predict inferior progression-free survival (PFS) (Hazard ratio (HR) = 3.40, p = 0.0003) and overall survival (OS) (HR = 4.91, p < 0.0001). In contrast to CA 19-9 kinetics, which were not predictive of outcome, integrated analysis of KRASmut cfDNA combined with six evaluated circulating protein biomarkers allowed basal risk stratification at the time of the first follow-up (HR = 10.2, p = 0.0014). Conclusions: A combined longitudinal analysis of KRASmut cfDNA with selected protein biomarkers offers significantly improved prognostic value for patients with mPDAC compared to single-parameter methods. This innovative approach is a step forward in the molecular monitoring of mPDAC and should be validated in further prospective studies. [ABSTRACT FROM AUTHOR]

Endometriosis is a chronic, estrogen-dependent disorder associated with the presence of endometrial cells mainly in the pelvic cavity, causing systemic immune inflammation, infertility, epigenetic dysregulation of differential DNA methylation, coelomic metaplasia, and pain. It affects approximately 10–12% of women. Despite decades of research, full pathophysiology, a diagnostic roadmap, and clinical management strategies for endometriosis are not yet fully elucidated. Cell-free DNA (Cf-DNA) in the peripheral blood of diseased and healthy individuals was discovered in the 1950s. Quantifying peripheral Cf-DNA and the specific differential methylation of a group of genes have been proposed as potential non-invasive diagnostic biomarkers for somatic and constitutional genetics and for various other pathological disorders. In this study, we investigated the Cf-DNA levels of 78 young women, 38 of whom had endometriosis confirmed via laparoscopy and 40 of whom were healthy. We found a significant difference between the two groups when Cf-DNA was quantified, with 3.9 times more Cf-DNA in the serum of women with endometriosis. We also identified nine target genes potentially involved in the pathogenesis of endometriosis, with a different methylation profile between the two groups. Our data suggest that the combination of cell-free DNA quantification and the assessment of the epigenetic signature of differential methylation of nine genes can be proposed as a non-invasive predictive and diagnostic test for endometriosis. [ABSTRACT FROM AUTHOR]

Objective: To report the diagnostic accuracy of cell‐free fetal DNA (cfDNA) in detecting fetal chromosomal anomalies in women experiencing miscarriage. Methods: PubMed, MEDLINE, EMBASE and Cochrane databases were searched from inception to June 2024. The inclusion criteria were women experiencing miscarriage (defined as pregnancy loss before 20 weeks of gestation) who underwent cfDNA screening for trisomies 21, 18 and 13, other autosomal aneuploidies, sex‐chromosome aneuploidies and/or copy‐number variants (CNVs). The index test was cfDNA screening for each of the chromosomal anomalies listed. The reference standard was cytogenetic analysis of pregnancy tissue. The quality of the studies was assessed using the revised tool for the quality assessment of diagnostic accuracy studies. Summary estimates of sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio were computed using the hierarchical summary receiver‐operating‐characteristics model. Results: Seven studies (887 women) were included in the systematic review and meta‐analysis. cfDNA had a sensitivity and specificity of 100% (95% CI, 81.5–100%) and 100% (95% CI, 99.1–100%), respectively, for trisomy 21, 100% (95% CI, 54.1–100%) and 100% (95% CI, 99.0–100%), respectively, for trisomy 18, and 88.9% (95% CI, 51.8–99.7%) and 100% (95% CI, 99.1–100%), respectively, for trisomy 13. The respective values for other autosomal trisomies were 75.8% (95% CI, 65.7–84.2%) and 99.4% (95% CI, 97.9–99.9%), while those for CNVs were 60.0% (95% CI, 14.7–94.7%) and 100% (95% CI, 97.4–100%). Failure of cfDNA testing was reported in 7.3% (95% CI, 5.7–9.2%) of cases. Conclusion: cfDNA has high diagnostic accuracy in detecting fetal trisomies 21, 18 and 13 in women experiencing miscarriage, while its accuracy for other autosomal aneuploidies and CNVs is only moderate. © 2024 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Background/Aim: Cholangiocarcinoma (CCA) is an aggressive hepatobiliary malignancy characterized by genomic heterogeneity. KRAS mutations play a significant role in influencing patient prognosis and guiding therapeutic decision-making. This study aimed to determine the prevalence and prognostic significance of KRAS mutations in CCA, asses the detection of KRAS G12/G13 mutations in plasma cell-free DNA (cfDNA), and evaluate the prognostic value of KRAS G12/G13 mutant allele frequency (MAF) in cfDNA in relation to clinicopathological data and patient survival. Materials and Methods: A retrospective analysis of 937 CCA patients was performed using data from cBioPortal to examine KRAS mutation profiles and their association with survival. Plasma from 101 CCA patients was analyzed for KRAS G12/G13 mutations in the cfDNA using droplet digital PCR, and the results were compared with tissuebased sequencing from 78 matched samples. Results: KRAS driver mutations were found in 15.6% of patients, with common variants being G12D (37.0%), G12V (24.0%) and Q61H (8.2%). Patients harboring KRAS mutations exhibited decreased overall and recurrence-free survival. KRAS G12/G13 mutations were detected in 14.9% of cfDNA samples, showing moderate concordance with tissue sequencing, and achieving 80% sensitivity and 93% specificity. Elevated KRAS G12/G13 MAF in cfDNA, combined with high CA19-9 levels, correlated with poorer survival outcomes. Conclusion: The presence of KRAS mutations was associated with poor survival in CCA, underscoring the importance of KRAS mutations as prognostic markers. The detection of KRAS mutations in cfDNA demonstrated potential as a promising non-invasive alternative for mutation detection and, when combined with CA19-9 levels, may improve prognostic efficacy in CCA. [ABSTRACT FROM AUTHOR]

The autonomous and active Long-Interspersed Element-1 (LINE-1, L1) and the non-autonomous Alu retrotransposon elements, contributing to 30% of the human genome, are the most abundant repeated sequences. With more than 90% of their sequences being methylated in normal cells, these elements undeniably contribute to the global DNA methylation level and constitute a major part of circulating-cell-free DNA (cfDNA). So far, the hypomethylation status of LINE-1 and Alu in cellular and extracellular DNA has long been considered a prevailing hallmark of ageing-related diseases and cancer. This study demonstrated that errors in LINE-1 and Alu methylation level measurements were caused by an excessive input quantity of genomic DNA used for bisulfite conversion. Using the minuscule DNA amount of 0.5 ng, much less than what has been used and recommended so far (500 ng-2 μg) or 1 μL of cfDNA extracted from 1 mL of blood, we revealed hypermethylation of LINE-1 and Alu in 407 tumour samples of primary breast, colon and lung cancers when compared with the corresponding pair-matched adjacent normal tissue samples (P < 0.05–0.001), and in cfDNA from 296 samples of lung cancers as compared with 477 samples from healthy controls (P < 0.0001). More importantly, LINE-1 hypermethylation in cfDNA is associated with healthy ageing. Our results have not only contributed to the standardized bisulfite-based protocols for DNA methylation assays, particularly in applications on repeated sequences but also provided another perspective for other repetitive sequences whose epigenetic properties may have crucial impacts on genome architecture and human health. [ABSTRACT FROM AUTHOR]

Donor-derived cell-free DNA (dd-cfDNA) is an emerging non-invasive biomarker for allograft injury detection. This study aimed to evaluate a new, decentralized dd-cfDNA testing kit against a centralized dd-cfDNA testing service broadly utilized in the United States. Kidney transplant recipients with decentralized and centralized dd-cfDNA measurements and concomitant kidney allograft biopsies were included in the study. 580 kidney allograft recipients from 3 referral centers were included for 603 total evaluations. Correlation between assays was evaluated using r-squared (r 2) and Spearman's rank correlation test, and associations with rejection using logistic regression analyses and discrimination using area under the curve. Mean dd-cfDNA levels from decentralized and centralized tests were 0.51% ± 0.81% and 0.43% ± 0.78%, respectively. The assays were highly correlated, with r 2 = 0.95 and Spearman's rank correlation 0.88 (p < 0.0001). Both tests showed significant association with allograft rejection (p < 0.0001) and good and similar discriminations to predict rejection (AUC: 0.758 for the decentralized and AUC: 0.760 for the centralized dd-cfDNA; p = 0.8466). Consistency between the assays was also confirmed across clinical scenarios including post-transplant timepoint, allograft stability, and allograft rejection subcategories. This decentralized dd-cfDNA assessment demonstrates high accuracy and value to non-invasively monitor kidney recipients. [ABSTRACT FROM AUTHOR]

Metastasis in patients with oral squamous cell carcinoma has been associated with a poor prognosis. However, sensitive and reliable tests for monitoring their occurrence are unavailable, with the exception of PET-CT. Circulating tumor cells and cell-free DNA have emerged as promising biomarkers for determining treatment efficacy and as prognostic predictors in solid tumors such as breast cancer and colorectal cancer. Hence, this study aimed to determine the potential role of liquid biopsy, circulating tumor cells, and cell-free DNA as biomarkers of oral squamous cell carcinoma. Thirteen patients with primary oral squamous cell carcinoma who visited our hospital between 2022 and 2023 were recruited, and plasma samples were collected from each patient preoperatively and postoperatively. We examined the relationship between the prognosis, the number of circulating tumor cells per four milliliters of peripheral blood, and the amount of cell-free DNA per milliliter of serum or the gene mutation in cell-free DNA. We observed no correlation between the number of preoperative circulating tumor cells and metastatic events. However, the number of circulating tumor cell clusters or the amount of preoperative cell-free DNA in metastatic cases was higher than that in non-metastatic cases. In oral squamous cell carcinoma, circulating tumor cell clusters or cell-free DNA levels may help inform management decisions regarding metastasis. However, further studies are required to provide a possible window for therapeutic interventions. [ABSTRACT FROM AUTHOR]

Esophageal adenocarcinoma (EAC) is an aggressive cancer characterized by a high risk of relapse post-surgery. Current follow-up methods (serum carcinoembryonic antigen detection and PET-CT) lack sensitivity and reliability, necessitating a novel approach. Analyzing cell-free DNA (cfDNA) from blood plasma emerges as a promising avenue. This study aims to evaluate the cost-effective and genome-wide cell-free reduced representation bisulfite sequencing (cfRRBS) method combined with computational deconvolution for effective disease monitoring in EAC patients. cfDNA methylation profiling with cfRRBS was performed on 162 blood plasma samples from 33 EAC cancer patients and 28 blood plasma samples from 20 healthy donors. The estimated tumor fraction for EAC patients at the time of diagnosis was significantly different from the healthy donor plasma samples (one-sided Wilcoxon rank-sum test: p-value = 0.032). Tumor fractions above 15% and focal gains/amplifications in MYC (chr8), KRAS (chr12), EGFR (chr7) and NOTCH2 (chr1) were observed in four samples of distinct patients at the time metastatic disease was detected. This study showed feasibility to estimate tumor fractions in blood plasma of EAC patients based on cfDNA methylation using cfRRBS and computational deconvolution. Nevertheless, in this study only cancer patients with evidence of metastatic disease show high tumor fractions and copy number alterations. [ABSTRACT FROM AUTHOR]

Background: Esophageal cancer (EC) is a highly lethal disease lacking early detection approaches. We previously identified that OTOP2 and KCNA3 were specifically hypermethylated in circulating cell-free DNA from patients with EC. We then developed a blood-based methylation assay targeting OTOP2 and KCNA3 (named "IEsohunter") for esophageal cancer noninvasive detection. This double-blinded, multicenter, prospective study aimed to comprehensively evaluate its clinical diagnostic performance. Methods: Participants with EC, high-grade intraepithelial neoplasia (HGIN), other malignancies, benign gastrointestinal lesions, or no abnormalities were prospectively enrolled from 5 tertiary referral centers across China. Peripheral blood samples were collected, followed by plasma cell-free DNA methylation analysis using the IEsohunter test based on multiplex quantitative polymerase chain reaction adopting an algorithm-free interpretation strategy. The primary outcome was the diagnostic accuracy of IEsohunter test for EC. Results: We prospectively enrolled 1116 participants, including 334 patients with EC, 71 with HGIN, and 711 controls. The areas under the receiver operating characteristic curves of the IEsohunter test for detecting EC and HGIN were 0.903 (95% CI 0.880–0.927) and 0.727 (95% CI 0.653–0.801), respectively. IEsohunter test showed sensitivities of 78.5% (95% CI 69.1–85.6), 87.3% (95% CI 79.4–92.4), 92.5% (95% CI 85.9–96.2), and 96.9% (95% CI 84.3–99.8) for stage I-IV EC, respectively, with an overall sensitivity of 87.4% (95% CI 83.4–90.6) and specificity of 93.3% (95% CI 91.2–94.9) for EC detection. The IEsohunter test status turned negative (100.0%, 47/47) after surgical resection of EC. Conclusions: The IEsohunter test showed high diagnostic accuracy for EC detection, indicating that it could potentially serve as a tool for noninvasive early detection and surveillance of EC. [ABSTRACT FROM AUTHOR]

The advent of non-invasive prenatal testing (NIPT) in the screening of fetal abnormalities has optimized prenatal care and decreased the rate of invasive diagnostic tests. In this retrospective descriptive study, we began with 1874 singleton pregnancies. After exclusion of some cases, the study cohort ended up with 1674 cases. We analyzed the performance of NIPT based on the results of first trimester screening (FTS) using serum screening combined with NT. The cases were also compared to diagnostic testing/pregnancy outcomes. Notably, in the subgroup with FTS risk < 1000, NIPT was reported to be normal in all cases with no false negative results. In the risk group of 1/300-1/1000, NIPT could detect all trisomy 21 cases with one false positive result. Moreover, in the risk group of 1/11 − 1/300, NIPT could detect all cases of trisomy 21, 13 and 18 with low false positive rate. However, the false positive rate for sex chromosomal abnormalities was high. Taken together, the current study confirms the applicability of NIPT as a tool for detection of fetal trisomies with high sensitivity and specificity. Yet, the high rate of false positive results for sex chromosome abnormalities should be considered in the interpretation of the results. [ABSTRACT FROM AUTHOR]

Glioma is the most common primary malignant brain tumor. Despite significant advances in the past decade in understanding the molecular pathogenesis of this tumor and exploring therapeutic strategies, the prognosis of patients with glioma remains poor. Accurate diagnosis of glioma is very important for the treatment and prognosis. Although the gold-standard method for the diagnosis and prognosis prediction of patients with glioma is tissue biopsy, it still has many limitations. Liquid biopsy can provide information on the auxiliary diagnosis and prognosis of gliomas. In this review, we summarized the application of cell-free DNA (cfDNA) and circulating tumor DNA (ctDNA) in the auxiliary diagnosis and prognosis of glioma. The common methods used to detect ctDNA in gliomas using samples including blood and cerebrospinal fluid (CSF) and the detection techniques for ctDNA, including droplet digital PCR (ddPCR) and next-generation sequencing (NGS), were discussed. Detection of ctDNA from plasma of patients with brain tumors remains challenging because of the blood–brain barrier (BBB). CSF has been proposed as a medium for ctDNA analysis in brain tumors, and mutation detection using plasma ctDNA was less sensitive than CSF ctDNA sequencing. Moreover, ongoing relevant clinical studies were summarized. Finally, we discussed the challenges, and future directions for the studies on ctDNA in glioma. [ABSTRACT FROM AUTHOR]

Background: Aberrant embryo implantation and suboptimal placentation can lead to (severe) complications such as preeclampsia and fetal growth restriction later in pregnancy. Current identification of high-risk pregnancies relies on a combination of risk factors, biomarkers, and ultrasound examinations, a relatively inaccurate approach. Previously, aberrant DNA methylation due to placental hypoxia has been identified as a potential marker of placental insufficiency and, hence, potential (future) pregnancy complications. The goal of the Early Prediction of prEgnancy Complications Testing, or the ExPECT study, is to validate a genome-wide, cell-free DNA (cfDNA) methylation strategy to diagnose preeclampsia accurately. More importantly, the predictive potential of this strategy is also explored to reliably identify high-risk pregnancies early in gestation. Furthermore, a longitudinal study was conducted, including sequential blood samples from pregnant individuals experiencing both uneventful and complicated gestations, to assess the methylation dynamics of cfDNA throughout these pregnancies. A significant strength of this study is its enzymatic digest, which enriches CpG-rich regions across the genome without the need for proprietary reagents or prior selection of regions of interest. This makes it useful for the cost-effective discovery of novel markers. Results: Investigation of methylation patterns throughout pregnancy showed different methylation trends between unaffected and affected pregnancies. We detected differentially methylated regions (DMRs) in pregnancies complicated with preeclampsia as early as 12 weeks of gestation, with distinct differences in the methylation profile between early and late pregnancy. Two classification models were developed to diagnose and predict preeclampsia, demonstrating promising results on a small set of validation samples. Conclusions: This study offers valuable insights into methylation changes at specific genomic regions throughout pregnancy, revealing critical differences between normal and complicated pregnancies. The power of noninvasive cfDNA methylation profiling was successfully proven, suggesting the potential to integrate this noninvasive approach into routine prenatal care. [ABSTRACT FROM AUTHOR]

The eLife article from December 18, 2024, details a proteomics study on circulating extracellular vesicles for biomarker discovery in pancreatic cancer. Researchers analyzed plasma samples from 124 individuals with various pancreatic diseases and controls, identifying a seven-protein signature that accurately diagnosed pancreatic cancer with an 89% prediction accuracy. The study underscores the significance of early detection in improving patient outcomes and offers valuable insights into potential biomarkers for pancreatic cancer diagnosis and prognosis. Conducted ethically with the approval of the Harvard Cancer Center Institutional Review Board, the research highlights the potential of extracellular vesicle proteins as biomarkers for pancreatic cancer. [Extracted from the article]

Background: Prostate cancer recurrence following primary treatment poses a significant clinical challenge, particularly when detected through biochemical recurrence at low PSA levels. Conventional imaging modalities often fail to localize the disease at this early stage. PSMA PET has demonstrated superior sensitivity in detecting recurrent lesions, even in patients with low PSA. Concurrently, liquid biopsy, through analysis of cell-free DNA (cfDNA), offers a minimally invasive approach for monitoring disease. There is scarce evidence about the association between liquid biopsy and PSMA PET/CT findings. This study aimed to assess the correlation between liquid biopsy and tumor burden assessed by PSMA PET/CT in early recurring prostate cancer patients. Results: PSMA PET/CT and liquid biopsies of 32 patients in biochemical recurrence were analyzed. 12 patients (37.5%) had no PSMA PET-measurable disease. Four patients (12.5%) presented local recurrence, seven (21.9%) had recurrence in pelvic lymph nodes, one of whom also had local recurrence. Nine patients (28.1%) presented metastatic recurrence, with or without local or nodal recurrence. PSA levels correlated with molecular imaging data (p < 0.05), including whole body PSMA-TV, whole body PSMA-TL, whole body SUVmean and whole body SUVmax. The mean cfDNA fragment size fraction was inversely correlated with tumour burden measured with whole body PSMA-TV, with a Spearman correlation coefficient of -0.451 and a p-value of 0.009. No correlation was found between cfDNA concentration and PET-PSMA data. Conclusion: This prospective study demonstrated a statistically significant negative correlation between cfDNA fragmentation patterns and PSMA PET/CT volumetric parameters in patients with presumed localized prostate cancer with early biochemical recurrence. These findings underscore the potential of liquid biopsy as a biomarker and a complementary tool to PSMA PET/CT to assess disease progression during the follow-up of these patients. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is the second leading cause of cancer death worldwide. Early detection of precursor lesions or early-stage cancer could hamper cancer development or improve survival rates. Liquid biopsy, which detects tumor biomarkers, such as mutations, in blood, is a promising avenue for cancer screening. Aim: To assess the presence of genetic variants in plasma cell-free tumor DNA from patients with precursor lesions and colorectal cancer using the commercial Oncomine Colon cfDNA Assay. Material and methods: Cell-free DNA (cfDNA) samples from the plasma of 52 Brazilian patients were analyzed. Eight patients did not have any significant lesions (five normal colonoscopies and three hyperplastic polyps), 24 exhibited precursor lesions (13 nonadvanced adenomas, 10 advanced adenomas, and one sessile serrated lesion), and 20 patients with cancer (CRC). The mutation profile of 14 CRC-associated genes were determined by next-generation sequencing (NGS) using the Oncomine Colon cfDNA Assay in the Ion Torrent PGM/S5 sequencer. Results: Thirty-three variants were detected in eight genes (TP53, PIK3CA, FBXW7, APC, BRAF, GNAS, KRAS, and SMAD4). No variants were detected in the AKT1, CTNNB1, EGFR, ERBB2, MAP2K1 and NRAS genes. All variants were considered pathogenic and classified as missense or truncating. The TP53 gene harbored the most variants (48.48%), followed by the KRAS gene (15.15%) and the APC gene (9.09%). It was possible to detect the presence of at least one pathogenic variant in cfDNA in 60% of CRC patients (12/20) and 25% of precursor lesions (6/24), which included variants in three patients with nonadvanced adenoma (3/13 – 23.08%) and three with advanced adenomas (3/10 – 30%). No variants were detected in the eight patients with normal findings during colonoscopy. The detection of mutations showed a sensitivity of 60% and a specificity of 100% for detecting CRC and a sensitivity of 50% and a specificity of 100% for detecting advanced lesions. Conclusion: The detection of plasma NGS-identified mutations could assist in early screening and diagnostic of CRC in a noninvasive manner. [ABSTRACT FROM AUTHOR]

Introduction: Detection of PIK3CA mutations in primary tumors and liquid biopsy samples is of increasing importance for treatment decisions and therapy resistance in many types of cancer. The aim of the present study was to directly compare the efficacy of a relatively inexpensive ultrasensitive real-time PCR with the well-established and highly sensitive technology of ddPCR for the detection of the three most common hotspot mutations of PIK3CA , in exons 9 and 20, that are all of clinical importance in various types of cancer. Patients and methods: We analyzed 42 gDNAs from primary tumors (FFPEs), 29 plasma-cfDNA samples, and 29 paired CTC-derived gDNAs, all from patients with ER+ metastatic breast cancer, and plasma from 10 healthy donors. The same blood draws were used for CTC isolation using EpCAM beads for positive immunomagnetic enrichment. All FFPEs and plasma-cfDNA samples were analyzed in parallel for PIK3CA mutations by ultrasensitive real-time PCR assay and droplet digital PCR. Results: In gDNAs from FFPEs, using ultrasensitive real-time PCR, the p.E545K mutation was detected in 22/42(52.4%), and the p.E542K and p.H1047R mutations were detected in 14/42(33.3%) and 16/42(38.1%), respectively. Using ddPCR, the p.E545K mutation was detected in 22/42(52.4%), p.E542K in 17/42(40.5%), and p.H1047R in 19/42(45.2%) samples, revealing a concordance between the two methodologies of 81%, 78.6% and 78.6% for each mutation respectively. In plasma-cfDNA, using ultrasensitive real-time PCR, the p.E545K mutation was detected in 11/29(38%) and both p.E542K and p.H1047R mutations in 2/29(6.9%).In the same plasma-cfDNA samples using ddPCR, p.E545K was detected in 1/29(3.5%), p.E542K in 2/29(6.9%), and p.H1047R in 3/29(10.5%) samples, revealing a concordance of 65.5%,100% and 93.1% for each mutation respectively. In paired CTC-derived gDNAs p.E545K was detected in 11/29(38%), p.E542K in 3/29(10.3%), and p.H1047R in 7/29(24.1%) samples. Conclusions: This low-cost, high-throughput and ultrasensitive real-time PCR assay provides accurate and specific detection of PIK3CA hotspot mutations in liquid biopsy samples and gives similar results to ddPCR. This assay can be performed in labs where digital PCR instrumentation is not available. In CTC-derived gDNA and paired plasma-cfDNA, PIK3CA mutations detected were not identical, revealing that CTC and plasma-cfDNA give complementary information. [ABSTRACT FROM AUTHOR]

Background: Retinal degeneration is a major cause of irreversible blindness. Stimulation with controlled low-level electrical fields, such as transcorneal electrical stimulation (TES), has recently been postulated as a therapeutic strategy. With promising results, there is a need for detailed molecular characterization of the therapeutic effects of TES. Methods: Controlled, non-invasive TES was delivered using a custom contact lens electrode to the retinas of Royal College of Surgeons (RCS) rats, a model of retinal degeneration. DNA methylation in the retina, brain and cell-free DNA in plasma was assessed by reduced representation bisulfite sequencing (RRBS) and gene expression by RNA sequencing. Results: TES induced DNA methylation and gene expression changes implicated in neuroprotection in the retina of RCS rats. We devised an epigenomic-based retinal health score, derived from DNA methylation changes observed with disease progression in RCS rats, and showed that TES improved the epigenomic health of the retina. TES also induced DNA methylation changes in the superior colliculus: the brain which is involved in integrating visual signaling. Lastly, we demonstrated that TES-induced retinal DNA methylation changes were detectable in cell-free DNA derived from plasma. Conclusion: TES induced DNA methylation changes with therapeutic effects, which can be measured in circulation. Based on these changes, we were able to devise a liquid biopsy biomarker for retinal health. These findings shed light on the therapeutic potential and molecular underpinnings of TES, and provide a foundation for the further development of TES to improve the retinal health of patients with degenerative eye diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: This review provides a comprehensive overview of advancements in melanoma biomarkers, emphasizing the potential of serologic biomarkers for early diagnosis, prognosis, and personalized treatment of melanoma. Notable markers include S100B and lactate dehydrogenase (LDH), already partially integrated into clinical practice, and new candidates like melanoma-inhibiting activity (MIA), osteopontin, and tumor-associated antigen 90 immune complex (TA90-IC), which offer predictive capabilities for treatment outcomes. New biomarkers, including genetic, proteomic, and cellular markers, are emerging as crucial tools. These biomarkers, such as circulating tumor DNA (ctDNA) and RNA, can offer real-time insights into tumor dynamics, enabling non-invasive monitoring through liquid biopsies. Additionally, tumor-educated platelets and circulating immune cells show promise in understanding melanoma's aggressive behavior. Lastly, the review discusses the integration of these biomarkers into clinical protocols and the need for continued research to establish these tools' accuracy, improving patient-specific treatment strategies. Melanoma is one of the most malignant cancers, and the global incidence of cutaneous melanoma is increasing. While melanomas are highly prone to metastasize if diagnosed late, early detection and treatment significantly reduce the risk of mortality. Identifying patients at higher risk of metastasis, who might benefit from early adjuvant therapies, is particularly important, especially with the advent of new melanoma treatments. Therefore, there is a pressing need to develop additional prognostic biomarkers for melanoma to improve early stratification of patients and accurately identify high-risk subgroups, ultimately enabling more effective personalized treatments. Recent advances in melanoma therapy, including targeted treatments and immunotherapy, have underscored the importance of biomarkers in determining prognosis and predicting treatment response. The clinical application of these markers holds the potential for significant advancements in melanoma management. Various tumor-derived genetic, proteomic, and cellular components are continuously released into the bloodstream of cancer patients. These molecules, including circulating tumor DNA and RNA, proteins, tumor cells, and immune cells, are emerging as practical and precise liquid biomarkers for cancer. In the current era of effective molecular-targeted therapies and immunotherapies, there is an urgent need to integrate these circulating biomarkers into clinical practice to facilitate personalized treatment. This review highlights recent discoveries in circulating melanoma biomarkers, explores the challenges and potentials of emerging technologies for liquid biomarker discovery, and discusses future directions in melanoma biomarker research. [ABSTRACT FROM AUTHOR]

Background: Cell loss and mitochondrial dysfunction are key pathological features of idiopathic Parkinson's disease (PD) and multiple system atrophy (MSA). It remains unclear whether disease-specific changes in plasma circulating cell-free nuclear DNA (cf-nDNA) and mitochondrial DNA (cf-mtDNA) occur in patients with PD and MSA. In this study, we investigated whether plasma cf-nDNA, cf-mtDNA levels, as well as cf-mtDNA integrity, are altered in patients with PD and MSA. Methods: TaqMan probe-based quantitative PCR was employed to measure plasma cf-nDNA levels, cf-mtDNA copy numbers, and cf-mtDNA deletion levels in 171 participants, including 76 normal controls (NC), 62 PD patients, and 33 MSA patients. A generalized linear model was constructed to analyze differences in circulating cell-free DNA (cfDNA) biomarkers across clinical groups, while a logistic regression model was applied to assess the predictive values of these biomarkers for developing PD or MSA. Spearman correlations were used to explore associations between the three cfDNA biomarkers, demographic data, and clinical scales. Results: No significant differences in plasma cf-nDNA levels, cf-mtDNA copy numbers, or cf-mtDNA deletion levels were observed among the PD, MSA, and NC groups (all P > 0.05). Additionally, these measures were not associated with the risk of developing PD or MSA. In PD patients, cf-nDNA levels were positively correlated with Hamilton Anxiety Rating Scale scores (Rho = 0.382, FDR adjusted P = 0.027). In MSA patients, cf-nDNA levels were positively correlated with International Cooperative Ataxia Rating Scale scores (Rho = 0.588, FDR adjusted P = 0.011) and negatively correlated with Montreal Cognitive Assessment scores (Rho = −0.484, FDR adjusted P = 0.044). Subgroup analysis showed that PD patients with constipation had significantly lower plasma cf-mtDNA copy numbers than those without constipation (P = 0.049). MSA patients with cognitive impairment had significantly higher cf-nDNA levels compared to those without (P = 0.008). Conclusion: Plasma cf-nDNA level, cf-mtDNA copy number, and cf-mtDNA deletion level have limited roles as diagnostic biomarkers for PD and MSA. However, their correlations with clinical symptoms support the hypothesis that cell loss and mitochondrial dysfunction are involved in PD and MSA development. [ABSTRACT FROM AUTHOR]

Open chromatin regions (OCRs) play a crucial role in transcriptional regulation and gene expression. In recent years, there has been a growing interest in using plasma cell-free DNA (cfDNA) sequencing data to detect OCRs. By analyzing the characteristics of cfDNA fragments and their sequencing coverage, researchers can differentiate OCRs from non-OCRs. However, the presence of noise and variability in cfDNA-seq data poses challenges for the training data used in the noise-tolerance learning-based OCR estimation approach, as it contains numerous noisy labels that may impact the accuracy of the results. For current methods of detecting OCRs, they rely on statistical features derived from typical open and closed chromatin regions to determine whether a region is OCR or non-OCR. However, there are some atypical regions that exhibit statistical features that fall between the two categories, making it difficult to classify them definitively as either open or closed chromatin regions (CCRs). These regions should be considered as partially open chromatin regions (pOCRs). In this paper, we present OCRClassifier, a novel framework that combines control charts and machine learning to address the impact of high-proportion noisy labels in the training set and classify the chromatin open states into three classes accurately. Our method comprises two control charts. We first design a robust Hotelling T2 control chart and create new run rules to accurately identify reliable OCRs and CCRs within the initial training set. Then, we exclusively utilize the pure training set consisting of OCRs and CCRs to create and train a sensitized T2 control chart. This sensitized T2 control chart is specifically designed to accurately differentiate between the three categories of chromatin states: open, partially open, and closed. Experimental results demonstrate that under this framework, the model exhibits not only excellent performance in terms of three-class classification, but also higher accuracy and sensitivity in binary classification compared to the state-of-the-art models currently available. [ABSTRACT FROM AUTHOR]

Circulating tumor DNA (ctDNA) in plasma cell free DNA (cfDNA) of cancer patients is associated with poor prognosis, but is challenging to detect from low plasma volumes. In metastatic castration-resistant prostate cancer (mCRPC), ctDNA assays are needed to prognosticate outcomes of patients treated with androgen receptor (AR) inhibitors. We develop a custom targeted cfDNA sequencing assay, named AR-ctDETECT, to detect ctDNA in limiting plasma cfDNA available from mCRPC patients in the Alliance A031201 randomized phase 3 trial of enzalutamide with or without abiraterone. Of 776 patients, 59% are ctDNA-positive, with 26% having high ctDNA aneuploidy and 33% having low ctDNA aneuploidy but displaying AR gain or structural rearrangement, MYC/MYCN gain, or a pathogenic mutation. ctDNA-positive patients have significantly worse median overall survival than ctDNA-negative patients (29.0 months vs. 47.4 months, respectively). Here, we show that mCRPC patients identified as ctDNA-positive using the AR-ctDETECT assay have poor survival despite treatment with potent AR inhibitors in a phase 3 trial. Liquid biopsy assays are important to prognosticate outcomes of metastatic castration-resistant prostate cancer (mCRPC) patients treated with androgen receptor (AR) inhibitors. Here this group reports detecting circulating tumor DNA in limiting plasma cell-free DNA of mCRPC patients as prognostic marker of poor survival after AR treatment. [ABSTRACT FROM AUTHOR]

Cell-free placental DNA (cfpDNA) is present in maternal circulation during gestation. CfpDNA carries great potential as a research and clinical tool as it provides a means to investigate the placental (epi)genome across gestation, which previously required invasive placenta sampling procedures. CfpDNA has been widely implemented in the clinical setting for noninvasive prenatal testing (NIPT). Despite this, the basic biology of cfpDNA remains poorly understood, limiting the research and clinical utility of cfpDNA. This review will examine the current knowledge of cfpDNA, including origins and molecular characteristics, highlight gaps in knowledge, and discuss future research directions. Author summary: Cell-free DNA are fragments of free-floating DNA released by cells into blood circulation. During pregnancy, the placenta releases cell-free placental DNA (cfpDNA) into maternal blood circulation. CfpDNA can be collected through a routine blood draw and is used for noninvasive prenatal testing (NIPT) to detect risk of the fetus having genetic abnormalities. There remains great untapped potential for the use of cfpDNA to screen not only for a wider range of fetal genetic abnormalities, but also for pregnancy complications affecting the health of both the fetus and pregnant person. This is currently hindered by a poor understanding of the "normal" characteristics of cfpDNA and how exactly it is released from placenta cells. In this review, we will summarize what is currently known about cfpDNA, highlight what remains unclear, and discuss future research directions for advancing the utility of cfpDNA in both research and the clinic. [ABSTRACT FROM AUTHOR]

The article "Shedding Light on Microvascular Inflammation: Understanding Outcomes, But What Sparks the Flame?" published in Transplant International explores the impact of different microvascular inflammation (MVI) phenotypes on allograft outcomes in kidney transplantation. The study, conducted by Drs. Sablik and Sannier with international collaborators, reclassified biopsy specimens according to the 2022 BANFF Classification of Renal Allograft Pathology, identifying new phenotypes like MVI without evidence of an antibody-mediated response. Patients with ABMR and MVI without antibody-mediated response showed increased risks of graft loss, emphasizing the importance of recognizing MVI as distinct histopathological phenotypes with different disease progression and allograft failure outcomes. The study highlights the necessity for broader acknowledgment of MVI phenotypes in clinical practice and the potential for tailored therapeutic strategies based on these insights. [Extracted from the article]

Background: Noninvasive prenatal testing (NIPT) is the most common method for prenatal aneuploidy screening. Low fetal fraction (LFF) is the primary reason for NIPT failure. Consequently, factors associated with LFF should be elucidated for optimal clinical implementation of NIPT. Methods: In this study, NIPT data from January 2019 to December 2022 from the laboratory records and obstetrical and neonatal data from the electronic medical records were collected and analyzed. Subjects with FF >3.50% were assigned to the control group, subjects with FF <3.50% once were assigned to the LFF group, and subjects with FF <3.50% twice were assigned to the repetitive low fetal fraction (RLFF) group. Factors, including body mass index (BMI), gestational age, maternal age, twin pregnancy, and in vitro fertilization (IVF) known to be associated with LFF were assessed by Kruskal–Wallis H test and logistic regression. Clinical data on first trimester pregnancy-associated plasma protein-A (PAPP-A), beta-human chorionic gonadotropin (β-hCG), gestational age at delivery, birth weight at delivery, and maternal diseases were obtained from the hospital's prenatal and neonatal screening systems (twin pregnancy was not included in the data on gestational age at delivery and the control group did not include data on maternal diseases.), and were analyzed using Kruskal–Wallis H test and Chi-square test. Results: Among the total of 63,883 subjects, 63,605 subjects were assigned to the control group, 197 subjects were assigned to the LFF group, and 81 subjects were assigned to the RLFF group. The median of BMI in the three groups was 22.43 kg/m2 (control), 25.71 kg/m2 (LFF), and 24.54 kg/m2 (RLFF). The median gestational age in the three groups was 130 days (control), 126 days (LFF), and 122/133 days (RLFF). The median maternal age in the three groups was 29 (control), 29 (LFF), and 33-years-old (RLFF). The proportion of twin pregnancies in the three groups was 3.3% (control), 10.7% (LFF), and 11.7% (RLFF). The proportion of IVF in the three groups was 4.7% (control), 11.7% (LFF), and 21.3% (RLFF). The factors significantly associated with LFF included BMI [2.18, (1.94, 2.45), p < 0.0001], gestational age [0.76, (0.67, 0.87), p < 0.0001], twin pregnancy [1.62, (1.02, 2.52), p = 0.0353], and IVF [2.68, (1.82, 3.86), p < 0.0001]. The factors associated with RLFF included maternal age [1.54, (1.17, 2.05), p = 0.0023] and IVF [2.55, (1.19, 5.54), p = 0.016]. Multiples of the median (MOM) value of β-hCG and pregnant persons' gestational age at delivery were significantly decreased in the LFF and RLFF groups compared to the control group. Conclusion: According to our findings based on the OR value, factors associated strongly with LFF include a high BMI and the use of IVF. Factors associated less strongly with LFF include early gestational age and twin pregnancy, while advanced maternal age and IVF were independent risk factors for a second LFF result. HIGHLIGHTS: Body mass index, gestational age, maternal age, twin pregnancy, and in vitro fertilization are associated with fetal fraction. We added the repetitive low fetal fraction population and used a large normal population as a control to identify the main factors associated with low fetal fraction. [ABSTRACT FROM AUTHOR]

Simple Summary: Optimal treatment strategies for HNSCC involve multidisciplinary tumor boards considering disease location, stage, and functional outcomes. While early-stage disease may be treated with single-modality approaches, locally advanced cases often require multimodal treatment. Despite aggressive therapies, local and distant recurrences remain a common challenge. Thus, a well-structured follow-up strategy is essential, with a focus on detecting recurrences within the first two years after treatment. However, due to the lack of standardized protocols and clear guidelines, clinical and radiological follow-up practices vary significantly among institutions, and their impact on patient survival remains uncertain. Background: For patients with head and neck squamous cell carcinoma (HNSCC), after a single or multi-modality treatment, a specific follow-up strategy is needed, but there is no agreement between the main international societies on the proper methods and timing of follow-up. Methods: We performed a descriptive review to evaluate the available data and compare the main guidelines, giving some practical guidance to perform effective personalized follow-up strategies. Results and Conclusions: While clinical and endoscopic follow-up alone seems to be appropriate for early-stage HNSCCs, the addition of close radiologic follow-up in locally advanced HNSCCs is still debated, as there are no data indicating that an earlier detection of recurrence correlates with increased survival, while it is mandatory in the first three-six months to define the response to treatment. For patients who have undergone conservative surgery or have major pathological risk factors, the incidence of locoregional recurrence is higher, and locoregional radiologic follow-up (magnetic resonance imaging is preferred to computed tomography) should be considered. Positron emission tomography may be useful in cases of suspected locoregional persistence of disease, differentiating it from post-irradiation outcomes. Distant radiological follow-up can be considered in the detection of the second primary in cases of specific risk factors and for virus-related tumors. For the latter, the use of circulating DNA should always be considered. A brain scan is not recommended without specific symptoms. For all patients who do not fall into the above categories, clinical and endoscopic follow-up should be proposed, reserving radiological investigations only at the onset of symptoms. [ABSTRACT FROM AUTHOR]

Introduction: Colorectal cancer screening programs are effective in reducing incidence and mortality. In Europe, every FIT+ patient is referred to colonoscopy. The available data show that ~75.0% of these patients are negative. It is desirable to select patients at a greater risk of having a positive colonoscopy. Materials and Methods: 711 subjects, aged 50–74, attending the screening program of ASL-NA-3-SUD (Naples, Italy), were enrolled in a cross-sectional study to evaluate the performance of the QuantiDNA™ test and the non-inferiority of an alternative approach (AAP). This evaluation is based on FIT+ and QuantiDNA™+ patients referred to colonoscopy, compared to Standard of Care (SOC) colonoscopy following a FIT+ test alone. A non-inferiority margin (NIM) for colorectal neoplasia (CN) and advanced adenomas (AA) was set at −10% and at −3.8% for CRC. Results: The odds ratio was 1.76 (p-value = 0.009). The detection rate of AAP was 15.9% for colorectal neoplasia, 13.0% for advanced adenoma, and 3.0% for CRC. The risk difference between AAP and SOC was −5.07% (95% C.I. −9.23, −0.90) for colorectal neoplasia, −4.02% (95% C.I. −7.89, −0.16) for advanced adenomas, and −1.04% (95% C.I. −3.16, 1.07) for CRC. This data suggests that AAP is non-inferior to SOC for detecting CN, AA, and CRC. The expected decrease in colonoscopies is 33.4%. Conclusions: The QuantiDNA™ test is straightforward, non-invasive, and well-tolerated. Data from this study indicate that it is effective in the reduction of the need for colonoscopy examinations (−33.4%) and is non-inferior to SOC in the detection of significant colorectal lesions. [ABSTRACT FROM AUTHOR]

Background Diagnosis of tuberculous pleural effusion (TPE) remains challenging. Studies have shown that detecting cell-free Mycobacterium tuberculosis (cf-TB) DNA in pleural effusion can improve TPE diagnosis. This study aimed to evaluate the diagnostic value of our recently developed TB One-Pot assay, which combines cross-priming amplification with CRISPR-Cas12b, in detecting cf-TB for TPE. Methods Pleural effusion samples were collected from inpatients with suspected TPE at Hangzhou Red Cross Hospital. After centrifugation, the precipitate was used for culture, Xpert, and pleural effusion cytologic testing, while the supernatant was used for biochemical and cf-TB assays, including TB One-Pot and the quantitative polymerase chain reaction method (cf-TB-PCR). Assessment of diagnostic performance was based on a comprehensive reference standard. Results A total of 115 patients were included: 88 TPE cases (diagnosed per the comprehensive reference standard) and 27 non-TPE cases. The sensitivity of TB One-Pot in detecting pleural cf-TB for diagnosing TPE was 64.8%, with an area under the curve (AUC) of 0.805, significantly superior to culture and Xpert (P <.05). When compared with cf-TB-PCR (sensitivity, 53.4%; AUC, 0.767) and the adenosine deaminase assay (sensitivity, 52.3%; AUC, 0.761), TB One-Pot demonstrated slightly higher sensitivity and AUC, but the differences were not statistically significant (P >.05). The specificity of TB One-Pot was 96.3%, while the specificity of the other tests was 100%, with no statistically significant differences (P >.05). Conclusions cf-TB provides direct evidence of the etiology of TPE. TB One-Pot for detecting cf-TB in diagnosing TPE outperforms existing TB laboratory tests and may represent a more effective approach for TPE diagnosis in resource-limited settings. [ABSTRACT FROM AUTHOR]