Expert Review of Molecular Diagnostics最新文献

Introduction: This special report explores the advancements of salivary biomarkers for early detection across various cancer types.

Areas covered: Saliva-based liquid biopsy has emerged as a promising diagnostic tool with a unique capability to capture a wide range of molecular signals that may reflect systemic disease signatures. Novel platforms such as Electric Field-Induced Release and Measurement (EFIRM) and next-generation sequencing (NGS)-based techniques are introduced. This report also addresses the challenges in standardizing saliva collection and biomarkers. Saliva diagnostics hold potential in changing the landscape of cancer detection and disease monitoring. However, barriers in reproducibility, sample variability, and accessibility must be addressed.

Expert opinion: We anticipate that through interdisciplinary collaborations, saliva-based diagnostic tools will be brought to the frontline of clinical practices for routine screening for cancer in the future, opening doors to earlier detection and increased accessibility to precision oncology.

Introduction: Traumatic brain injury (TBI) is a leading cause of death and disability worldwide, with current diagnostic tools often inadequate for predicting long-term outcomes. Omics studies have identified specific biomarkers for TBI, and recently, glycoproteins have emerged as promising novel biomarkers due to their pivotal roles in cellular signaling and structural integrity.

Areas covered: This review explores the biological significance of glycoproteins in TBI, their altered glycosylation patterns post-injury, and their role as diagnostic and prognostic indicators. We summarize analytical techniques for glycoprotein detection, such as mass spectrometry and antibody-based assays. Key glycoproteins, including neurofilament proteins, GFAP, tau, and amyloid precursor proteins, are examined for clinical relevance. This review addresses challenges in glycoprotein biomarker research, like glycosylation complexity and the need for precise detection methods.

Expert opinion: Clinical research from our lab and others have underscored the role of glycoproteins in diagnosing TBI, assessing injury severity, and guiding therapeutic strategies. By addressing the current state and future directions of glycoprotein research, we aim to potentially highlight the path toward improved diagnostic and therapeutic approaches for TBI.

Background: Huntington's disease (HD) is a neurodegenerative condition resulting from CAG trinucleotide expansion in the HTT. We reviewed various molecular tools for diagnosing HD and their respective validations and outlined their advantages and disadvantages.

Methods: We utilized PubMed, employing Huntington's disease OR chorea AND Molecular Diagnosis OR Molecular Diagnostic Techniques as keywords. This review was submitted to the PROSPERO platform (nºCRD42021253951). The PRISMA checklist was used, and bias assessment followed the guidelines outlined in the Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy.

Results: 845 articles were retrieved, 17 were selected for full-text review, and two additional articles were manually included, resulting in 19 that presented the validation method: only three studies reported the limits of detection, reproducibility, sensitivity, and specificity, which are essential for validating these techniques, given the unstable nature of CAG regions; six calculated at least one of these parameters, and 10 did none.

Conclusion: We identified significant variability in the validation methods with only three thoroughly assessing the key validation parameters. The lack of standardized validation approaches may compromise diagnostic accuracy, impacting genetic counseling and clinical management. TPPCR coupled with capillary electrophoresis, demonstrated high accuracy, whereas gel electrophoresis-based methods exhibited lower sensitivity and specificity.

Introduction: Circulating tumor DNA (ctDNA) is a noninvasive and promising biomarker for cancer diagnosis, prognosis, and therapeutic monitoring, offering significant potential for real-time insights into tumor dynamics when compared to traditional tissue-based biopsies. Phase I oncology clinical trials, which primarily focus on assessing the safety, pharmacodynamics, and early activity of novel cancer therapies, might find in the unique biological characteristics of ctDNA, a valuable biomarker to boost the efficiency of testing novel agents.

Areas covered: This review explores the utility of ctDNA as a biomarker in phase I trials, discussing its biological and technical features, clinical relevance, current limitations, and future potential in advancing early clinical drug development.

Expert opinion: Despite being an emerging field in phase I trials, ctDNA analysis has proved to be a remarkable tool for patient inclusion, optimal biological dose determination, and early response assessment. However, several challenges hinder its systematic adoption in early trials, including assay variability, biological and anatomical differences across cancer types, and, most notably, the lack of standardization. Systematic implementation of ctDNA in phase I trials could facilitate the development of robust, reproducible noninvasive biomarker models, which can then be further validated in phae II/III trials.

Introduction: Tumor necrosis factor inhibitors (TNFi) have revolutionized rheumatic and inflammatory diseases therapy. Despite their efficacy, at least 30% of patients do not respond to TNFi therapy. There are five FDA-approved TNFis and several TNFi biosimilars, which are equivalent to their reference drugs. Although all TNFi drugs neutralize the TNF cytokine, they differ in many structural and pharmacokinetic properties. These differences may lead to varying patient responses, making one TNFi, but not another, effective for a given patient. An accurate prediction of a priori responsiveness to therapy, rather than trial and error, would therefore be of great value. Biomarkers that may guide the optimal TNFi choice are an unmet need.

Areas covered: The authors discuss the diagnostic and predictive utilities of Cell-Based Assays (CBAs) for individualized TNFi therapy. Selection of TNFi can be based upon a given patient's immune cell response to the various TNFi drugs to predict their clinical outcomes to those drugs.

Expert opinion: CBAs allow to assess the response of multiple TNFi drugs simultaneously by measuring biomarkers that could distinguish between TNFi responders and non-responders, effectively prioritizing the TNFi of choice. This literature search focuses on biomarkers and techniques that could be used as predictive CBAs for clinical response to TNFi.

Introduction: Diagnosing severe pneumonia accurately is often difficult because its clinical symptoms overlap with other respiratory illnesses. Treatment of severe lower respiratory tract infection (LRTI) should start early. Rapid identification of responsible microorganisms and appropriate, not overly broad, antibiotic therapy is required to optimize prognosis. Unfortunately, the causative pathogen is often unidentified in pneumonia patients, and conventional bacterial cultures lack sensitivity and have slow turnaround times. Multiplex PCR (mPCR) respiratory panels, which quickly detect multiple bacterial pathogens, some common respiratory viruses, and key resistance genes, have become commercially available and may help achieve these objectives.

Areas covered: The authors will describe the available biological and clinical data on the benefits of mPCR in severe LRTI.

Expert opinion: mPCR offers early pathogen and resistance detection. However, mPCR panels do not detect all bacterial pathogens and may not differentiate between colonizing and infecting organisms. Detectable resistance genes do not always indicate phenotypic resistance. It should only be used in patients with adequate lower respiratory tract (LRT) samples. Additionally, evidence on whether mPCR panels improve antimicrobial use and patient outcomes remains limited and conflicting. This review provides a thorough overview of the rationale and clinical evidence for the use of mPCR panels for the detection of viral and bacterial pathogens in pneumonia diagnosis and management, as well as future research directions. [Figure: see text].

Introduction: Liquid biopsy (LB) has shifted the paradigm in cancer diagnosis and management, offering a minimally invasive and dynamic approach to understanding tumor biology. Advanced next-generation sequencing (NGS) technologies have significantly improved the accuracy of LB results, enhancing both its analytical and clinical validity. However, tissue biopsy (TB) remains the gold standard for molecular analysis, often negatively impacting the molecular profiling of tumor patients owing to inadequate tissue samples, or lack thereof.

Areas covered: In this scenario, LB has become a dynamic and easily-to-handle, integrative source of nucleic acids, filling the gap in tissue sample availability for molecular profiling. Moreover, cost-effectiveness analyses have also shown that when LB is correctly applied to clinical settings, healthcare spending can be optimized, enabling an increase in quality-adjusted life years at an affordable cost.

Expert opinion: While LB has the potential to reduce the need for invasive TB and expedite treatment decisions, its cost-effectiveness hinges on long-term clinical outcomes and healthcare resource utilization. In this scenario, 'new era platforms' endowed with advanced liquid handling technologies could not only improve its efficiency and reduce costs but also enable higher-throughput experiments with much larger sample sizes.

Introduction: Despite vaccine availability, Hepatitis B Virus (HBV) remains a major global health threat, especially in areas with low vaccination coverage and poor healthcare. Around 250 million people are chronically infected. Achieving the World Health Organisation's (WHO) 2030 eradication goal is difficult, particularly due to diagnostic challenges in low-resource settings. While HBsAg detection is standard, low antigen levels and mutations hinder its reliability. Though molecular methods for HBV DNA offer high specificity, their cost and complexity limit use in under-resourced areas. Isothermal amplification emerges as a promising alternative, offering a more affordable, effective, and simplified approach to HBV detection, potentially improving access to timely diagnosis and care.

Areas covered: This review evaluates the efficacy of various isothermal techniques to give insights into their benefits and limits, guiding researchers and clinicians in selecting the most effective assays for HBV molecular diagnostics.

Expert opinion: Recombinase Polymerase Amplification (RPA) and Polymerase Spiral Reaction (PSR) are the most promising isothermal assays for HBV detection in field settings. RPA is faster (∼20 min), works at low temperatures (37-42 °C), and uses stable lyophilized reagents, while PSR is simple, can be clubbed with visual detection, making both ideal for a low-resource setup.