Liquid biopsy enters the clinic - implementation issues and future challenges

Enhancing Electrochemical Biosensing of Circulating Nucleic Acids at the Electrode-Biomolecule-Electrolyte Interfaces

The detection and analysis of circulating cell-free nucleic acid (ccfNA) biomolecules are redefining a new era of molecular targeted cancer therapies. However, the clinical translation of electrochemical ccfNA biosensing remains hindered by unresolved challenges in analytical specificity and sensitivity. In this Perspective, we present a novel electrochemical framework for improving ccfNA biosensor performance by optimizing the critical electrode-biomolecules-electrolyte interfaces. We highlight and elucidate related research works on modification-free electrode sensor surfaces, nucleic acids as biological scaffolds, and redesigning redox reporter systems. We conclude by providing an outlook into the future research developments of ccfNA electrochemical biosensing, emphasizing the potential to overcome current analytical limitations by controlling the complex interplay of target biomolecules and redox species at the electrode surface. These advances are poised to significantly impact the development of electrochemical ccfNA technologies, improving both cancer diagnostics and therapeutic monitoring.

Further Optimizing Care of Patients With Operable Hormone Receptor-Sensitive Breast Cancer

Harmonized global collaborations are crucial to improving outcomes in hormone sensitive operable breast cancer.

Testing BRCA 1-2 Mutations in Metastatic Prostate Cancer: Results of a Survey of the Italian Association of Medical Oncology

BACKGROUND

20% of prostate cancer (PC) patients harbor germinal or somatic alterations in homologous recombination repair (HRR) genes, including BRCA1/2. BRCA mutations represent predictive biomarkers for treatment with polyadenosine diphosphate-ribose inhibitors (PARPi). Olaparib has shown efficacy in metastatic castration-resistant PC (mCRPC) and is currently approved in Italy for mCRPC with BRCA1/2 mutations. National and international guidelines strongly recommend BRCA testing in PC. However, genetic testing presents challenges in clinical practice that may limit access to PARPi.

METHODS

we conducted a survey directed towards members of the Italian Association of Medical Oncology to highlight the level of implementation of national recommendations and issues associated with genetic testing. Through an anonymous questionnaire, the survey collected clinical data of PC patients undergoing BRCA testing and the main difficulties to face in conducting the analysis.

RESULTS

The survey was completed by 108 participants (5% of AIOM members). 52.8% of respondents test BRCA in all metastatic PC patients. If tissue analysis is invalid, only 17% use liquid biopsy, and 15.7% always consider a re-biopsy of a metastatic lesion. A quarter of respondents have to outsource genetic testing to another center and 17.6% have a split process between different institutions. Long timelines, lack of a predefined procedure, and unavailability of liquid biopsy represent the main issues based on respondents' opinions.

CONCLUSIONS

BRCA testing in PC still presents several difficulties in clinical practice that can limit access to PARPi treatment. Better implementation of molecular testing to identify BRCA-mutated patients is crucial for tailored treatment in mCRPC.

The changing treatment landscape of EGFR-mutant non-small-cell lung cancer

The discovery of the association between EGFR mutations and the efficacy of EGFR tyrosine-kinase inhibitors (TKIs) has revolutionized the treatment paradigm for patients with non-small-cell lung cancer (NSCLC). Currently, third-generation EGFR TKIs, which are often characterized by potent central nervous system penetrance, are the standard-of-care first-line treatment for advanced-stage EGFR-mutant NSCLC. Rational combinations of third-generation EGFR TKIs with anti-angiogenic drugs, chemotherapy, the EGFR-MET bispecific antibody amivantamab or local tumour ablation are being investigated as strategies to delay drug resistance and increase clinical benefit. Furthermore, EGFR TKIs are being evaluated in patients with early stage or locally advanced EGFR-mutant NSCLC, with the ambitious aim of achieving cancer cure. Despite the inevitable challenge of acquired resistance, emerging treatments such as new TKIs, antibody-drug conjugates, new immunotherapeutic approaches and targeted protein degraders have shown considerable promise in patients with progression of EGFR-mutant NSCLC on or after treatment with EGFR TKIs. In this Review, we describe the current first-line treatment options for EGFR-mutant NSCLC, provide an overview of the mechanisms of acquired resistance to third-generation EGFR TKIs and explore novel promising treatment strategies. We also highlight potential avenues for future research that are aimed at improving the survival outcomes of patients with this disease.

Bile-Derived cfDNA of Syncytin-1 and SLC7A11 as a Potential Molecular Marker for Early Diagnosis of Cholangiocarcinoma

PURPOSE

Liquid biopsy technology has received widespread attention in the early diagnosis of cholangiocarcinoma (CCA).

METHODS

We collected bile samples from 48 patients with CCA and 48 patients with gallstones at Shandong Provincial third Hospital. We quantified bile circulating free DNA (cfDNA) of syncytin-1 and SLC7A11, calculated the correlation between syncytin-1 and SLC7A11 expression and clinical parameters by Spearman rank correlation, plotted Receiver Operating Characteristic (ROC) curves, and compared the Area Under Curve (AUC) values to explored early diagnostic utility in patients.

RESULTS

We first found the bile cfDNA of syncytin-1 and SLC7A11 levels in CCA were higher than in gallstones (3.06 vs. 1.32, p < 0.001; 2.39 vs. 1.30, p < 0.001). And there was significant correlation between syncytin-1 and SLC7A11 expression (p = 0.025). Additionally, bile cfDNA of syncytin-1 or SLC7A11 was differentially expressed in gallstones, cholangiocarcinoma stage I-II, and cholangiocarcinoma stage III-IV (p < 0.001; p < 0.001). The AUC of bile cfDNA of syncytin-1 was 0.805 (p < 0.001, specificity of 87.0%), the AUC of bile cfDNA of SLC7A11 was 0.755 (p < 0.001, specificity of 80.4%), and combination of bile cDNA of syncytin-1/SLC7A11/CA19-9 markers improved diagnostic efficiency in CCA patients (AUC: 0.927, p < 0.001).

CONCLUSION

The bile cfDNA of syncytin-1 and SLC7A11 was high expression in cholangiocarcinoma, which may be used as a novel biomarker for early diagnosis.

Atomic force microscopy combined with microfluidics for label-free sorting and automated nanomechanics of circulating tumor cells in liquid biopsy

Liquid biopsies are expected to advance cancer management, and particularly physical cues are gaining attention for indicating tumorigenesis and metastasis. Atomic force microscopy (AFM) has become a standard and important tool for detecting the mechanical properties of single living cells, but studies of developing AFM-based methods to efficiently measure the mechanical properties of circulating tumor cells (CTCs) in liquid biopsy for clinical utility are still scarce. Herein, we present a proof-of-concept study based on the complementary combination of AFM and microfluidics, which allows label-free sorting of individual CTCs and subsequent automated AFM measurements of the mechanical properties of CTCs. With the use of a microfluidic system containing contraction-expansion microchannels, specific cancer cell types were separated and harvested in a marker-independent manner. Subsequently, automated AFM indentation and force spectroscopy experiments were performed on the enriched cells under the precise guidance of the label-free identification of cells using a deep learning optical image recognition model. The effectiveness of the presented method was verified on three experimental sample systems, including mixed microspheres with different sizes, a mixture of different types of cancer cells, and a mixture of cancer cells and blood cells. The study illustrates a feasible framework based on the integration of AFM and microfluidics for non-destructive and efficient nanomechanical phenotyping of CTCs in bodily fluids, which offers additional possibilities for the clinical applications of AFM-based nanomechanical analysis and will also benefit the field of mechanobiology as well as cancer liquid biopsy.

Detection of Circulating Tumor DNA in Liquid Biopsy: Current Techniques and Potential Applications in Melanoma

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.

Circulating tumour DNA in early stage and locally advanced NSCLC: ready for clinical implementation?

Circulating tumour DNA (ctDNA) can be released by cancer cells into biological fluids through apoptosis, necrosis or active release. In patients with non-small-cell lung cancer (NSCLC), ctDNA levels correlate with clinical and pathological factors, including histology, tumour size and proliferative status. Currently, ctDNA analysis is recommended for molecular profiling in patients with advanced-stage NSCLC. In this Review, we summarize the increasing evidence suggesting that ctDNA has potential clinical applications in the management of patients with early stage and locally advanced NSCLC. In those with early stage NSCLC, detection of ctDNA before and/or after surgery is associated with a greater risk of disease recurrence. Longitudinal monitoring after surgery can further increase the prognostic value of ctDNA testing and enables detection of disease recurrence earlier than the assessment of clinical or radiological progression. In patients with locally advanced NSCLC, the detection of ctDNA after chemoradiotherapy is also associated with a greater risk of disease progression. Owing to the limited number of patients enrolled and the different technologies used for ctDNA testing in most of the clinical studies performed thus far, their results are not sufficient to currently support the routine clinical use of ctDNA monitoring in patients with early stage or locally advanced NSCLC. Therefore, we discuss the need for interventional studies to provide evidence for implementing ctDNA testing in this setting.

Next-generation sequencing-based evaluation of the actionable landscape of genomic alterations in solid tumors: the "MOZART" prospective observational study

BACKGROUND

The identification of the most appropriate targeted therapies for advanced cancers is challenging. We performed a molecular profiling of metastatic solid tumors utilizing a comprehensive next-generation sequencing (NGS) assay to determine genomic alterations' type, frequency, actionability, and potential correlations with PD-L1 expression.

METHODS

A total of 304 adult patients with heavily pretreated metastatic cancers treated between January 2019 and March 2021 were recruited. The CLIA-/UKAS-accredit Oncofocus assay targeting 505 genes was used on newly obtained or archived biopsies. Chi-square, Kruskal-Wallis, and Wilcoxon rank-sum tests were used where appropriate. Results were significant for P < .05.

RESULTS

A total of 237 tumors (78%) harbored potentially actionable genomic alterations. Tumors were positive for PD-L1 in 68.9% of cases. The median number of mutant genes/tumor was 2.0 (IQR: 1.0-3.0). Only 34.5% were actionable ESCAT Tier I-II with different prevalence according to cancer type. The DNA damage repair (14%), the PI3K/AKT/mTOR (14%), and the RAS/RAF/MAPK (12%) pathways were the most frequently altered. No association was found among PD-L1, ESCAT, age, sex, and tumor mutational status. Overall, 62 patients underwent targeted treatment, with 37.1% obtaining objective responses. The same molecular-driven treatment for different cancer types could be associated with opposite clinical outcomes.

CONCLUSIONS

We highlight the clinical value of molecular profiling in metastatic solid tumors using comprehensive NGS-based panels to improve treatment algorithms in situations of uncertainty and facilitate clinical trial recruitment. However, interpreting genomic alterations in a tumor type-specific manner is critical.

Role of the International Society of Liquid Biopsy (ISLB) in establishing quality control frameworks for clinical integration

Liquid biopsy (LB) has revolutionized molecular pathology, offering non-invasive insights into tumor biology. However, widespread adoption is hindered by a lack of standardized protocols, requiring robust quality control and harmonized workflows. Large-scale studies are needed to establish effective standard operating procedures (SOPs), particularly for circulating tumor DNA (ctDNA) assays tailored to different disease stages. The International Society of Liquid Biopsy (ISLB) has addressed these challenges by forming a Quality Control and Accreditation Committee, focused on developing frameworks for pre-analytical, analytical, and interpretive processes. Key priorities include mitigating pre-analytical variability with stringent guidelines for blood handling and ensuring adherence to international standards like ISO 15189 and CLIA/CAP. ISLB emphasizes harmonized methodologies, with advanced techniques like droplet digital PCR and next-generation sequencing requiring unified workflows. Collaboration with global initiatives, including the European Society of Medical Oncology (ESMO), American Society of Clinical Oncology (ASCO), and International Liquid Biopsy Standardization Alliance (ILSA), supports the validation of ctDNA testing. These efforts are vital for integrating LB into clinical care, advancing precision oncology, and improving patient outcomes through reliable and standardized applications.

Leveraging nanomaterials for ultrasensitive biosensors in early cancer detection: a review

Cancer remains a major global health challenge with a high mortality rate, as evidenced by the rise in new cases every year. Conventional diagnostic methods like PET scans, MRIs, and biopsies, despite being widely used, suffer from significant drawbacks such as high radiation exposure, difficulty in distinguishing malignant from benign tumors, and invasiveness. Early detection, which is crucial for improving treatment outcomes and survival rates, is hindered by the asymptomatic nature of early-stage cancer and the limitations of current diagnostic tools. Cancer biomarkers, detectable in body fluids, offer valuable diagnostic information, and recent advances in nanotechnology have led to the development of highly sensitive nano-biosensors. This review explores recent advancements (2022-2024) in the field of ultrasensitive nano-biosensors, emphasizing the strategic integration of nanomaterials to enhance sensitivity and accuracy in cancer biomarker detection. It highlights how precise nanomaterial positioning in sensor components like electrodes and bioreceptors enables early cancer diagnosis at low biomarker concentrations. These innovations underscore the transformative potential of nanomaterials in revolutionizing early cancer diagnostics, improving patient care, and enhancing survival outcomes.

Longitudinal genomic profiling using liquid biopsies in metastatic nonsquamous NSCLC following first line immunotherapy

Tumor genomic profiling is often limited to one or two timepoints due to the invasiveness of tissue biopsies, but longitudinal profiling may provide deeper clinical insights. Using ctDNA data from IMpower150 study, we examined genetic changes in metastatic non-squamous NSCLC post-first-line immunotherapy. Mutations were most frequently detected in TP53, KRAS, SPTA1, FAT3, and LRP1B at baseline and during treatment. Mutation levels rose prior to radiographic progression in most progressing patients, with specific mutations (SPTA1, STK11, KEAP1, SMARCA4, TBX3, CDH2, and MLL3) significantly enriched in those with progression or nondurable response. However, ctDNA's role in detecting hyperprogression and pseudoprogression remains uncertain. STK11, SMARCA4, KRAS, SLT2, and KEAP1 mutations showed the strongest correlation with poorer overall survival, while SMARCA4, STK11, SPTA1, TBX3, and KEAP1 mutations correlated with shorter progression-free survival. Overall, longitudinal liquid biopsy profiling provided valuable insights into lung cancer biology post-immunotherapy, potentially guiding personalized therapies and future drug development.

Size-Coded Hydrogel Microbeads for Extraction-Free Serum Multi-miRNAs Quantifications with Machine-Learning-Aided Lung Cancer Subtypes Classification

Classifying lung cancer subtypes, which are characterized by multi-microRNAs (miRNAs) upregulation, is important for therapy and prognosis evaluation. Liquid biopsy is a promising approach, but the pretreatment of RNA extraction is labor-intensive and impairs accuracy. Here we develop size-coded hydrogel microbeads for extraction-free quantification of miR-21, miR-205, and miR-375 directly from serum. The hydrogel microbead is immobilized with an miRNA capture probe, which well retains target miRNA and provides good nonfouling capability for nonspecific biomolecules in serum. The porous structure of microbeads allows efficient DNA cascade amplification reaction and generates a fluorescence signal. The microbeads are clustered into three groups according to size via flow cytometry sorting, and the group fluorescence is integrated for the corresponding miRNA quantification. With machine-learning-assisted data analysis, it achieves good lung cancer diagnosis accuracy and 80% accuracy for subtype classification for 108 serum samples, including lung cancer patients and healthy controls.

Minimal residue disease detection in early-stage breast cancer: a review

Over the past five years, circulating tumor DNA (ctDNA) testing has emerged as a game-changer in cancer research, serving as a less invasive and highly sensitive method to monitor tumor dynamics. CtDNA testing has a wide range of potential applications in breast cancer (BC) management, including diagnosis, monitoring treatment responses, identifying resistance mutations, predicting prognosis, and detecting future relapses. In this review, we focus on the prognostic and predictive value of ctDNA testing for BC in both neoadjuvant and adjuvant settings. We also examine the rationale behind mainstream minimal residue disease (MRD) tracking methods and highlight key considerations for successful MRD testing. Clinical evidence has shown that ctDNA-based MRD testing can accurately detect molecular relapse 8-12 months before clinical relapse in early-stage BC. Compared to advanced-stage BC, detecting ctDNA in early-stage BC is more challenging and requires ultra-sensitive testing methods due to the low levels of ctDNA released into the bloodstream, particularly in post-surgical settings, after effective neoadjuvant chemotherapy, and in late adjuvant settings that require longer follow-up. Therefore, future efforts are needed to generate additional clinical evidence in these settings to support the clinical utility and widespread adoption of ctDNA-based MRD testing.

Diagnostic accuracy of MRI-based radiomic features for EGFR mutation status in non-small cell lung cancer patients with brain metastases: a meta-analysis

Objective

This meta-analysis aims to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) based radiomic features for predicting epidermal growth factor receptor (EGFR) mutation status in non-small cell lung cancer (NSCLC) patients with brain metastases.

Methods

We systematically searched PubMed, Embase, Cochrane Library, Web of Science, Scopus, Wanfang, and China National Knowledge Infrastructure (CNKI) for studies published up to April 30, 2024. We included those studies that utilized MRI-based radiomic features to detect EGFR mutations in NSCLC patients with brain metastases. Sensitivity, specificity, positive and negative likelihood ratios (PLR, NLR), and area under the curve (AUC) were calculated to evaluate the accuracy. Quality assessment was performed using the quality assessment of prognostic accuracy studies 2 (QUADAS-2) tool. Meta-analysis was conducted using random-effects models.

Results

A total of 13 studies involving 2,348 patients were included. The pooled sensitivity and specificity of MRI-based radiomic features for detecting EGFR mutations were 0.86 (95% CI: 0.74-0.93) and 0.83 (95% CI: 0.72-0.91), respectively. The PLR and NLR were calculated as 5.14 (3.09, 8.55) and 0.17 (0.10, 0.31), respectively. Substantial heterogeneity was observed, with I² values exceeding 50% for all parameters. The AUC for the receiver operating characteristic analysis was 0.91 (95% CI: 0.88-0.93). Subgroup analysis indicated that deep learning models and studies conducted in Asian showed higher diagnostic accuracy compared to their respective counterparts.

Conclusions

MRI-based radiomic features demonstrate a high potential for accurately detecting EGFR mutations in NSCLC patients with brain metastases, particularly when advanced deep learning techniques were employed. However, the variability in diagnostic performance across different studies underscores the need for standardized radiomic protocols to enhance reproducibility and clinical utility.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024544131.

Prognostic value of circulating tumor DNA at diagnosis and its early decrease after one cycle of neoadjuvant chemotherapy for patients with advanced epithelial ovarian cancer. An ancillary analysis of the CHIVA phase II GINECO trial

OBJECTIVE

To evaluate the prognostic impact of circulating tumor DNA (ctDNA) detection at diagnosis (T0) and its early decrease after one cycle (T1) of neoadjuvant chemotherapy (NACT) in patients with advanced epithelial ovarian cancer (EOC) included in the CHIVA trial (NCT01583322).

METHODS

Blood samples were collected at T0 and before each administration of NACT. Circulating tumor DNA detection was performed by next-generation sequencing. Multivariate analysis was performed. A p-value of 0.05 was considered significant. Progression-free survival (PFS) and overall survival (OS) were compared between groups defined by ctDNA kinetic profile. Cox survival model was used to search variables associated with PFS and OS. Kaplan-Mayer curve was used to graphically express the differences in PFS and OS. A log-rank test compared the two curves.

RESULTS

188 patients were included. Blood samples were available for 168 patients at T0 and for 160 patients at T0 and T1 to assess ctDNA ratio kinetics. At T0, 107 patients (63.7 %) had detectable ctDNA. At T1, 137 (85.6 %) patients had negative ctDNA or a decrease of more than 80 %. There was a significant benefit in either PFS (p = 0.0017) or OS (p = 0.0036) in favor of early decrease of ctDNA ratio. A favorable decrease was associated with a greater likelihood of being able to perform CRS (OR: 3.94 (CI95 % 1.45-10.70), p = 0.0074).

CONCLUSIONS

Early decrease of ctDNA ratio can provide prognostic information early in the management of patients, allowing a more accurate information to patients and an early preparation for CRS (prehabilitation).

Liquid Biopsy for Spinal Tumors: On the Frontiers of Clinical Application

STUDY DESIGN

Narrative review.

OBJECTIVES

This article aims to provide a narrative review of the current state of research for liquid biopsy in spinal tumors and to discuss the potential application of liquid biopsy in the clinical management of patients with spinal tumors.

METHODS

A comprehensive review of the literature was performed using PubMed, Google Scholar, Medline, Embase and Cochrane databases, and the review was limited to articles of English language. All the relevant articles which were identified to be related to liquid biomarker study in spinal tumors, were studied in full text.

RESULTS

Liquid biopsy has revolutionized the field of precision medicine by guiding personalized clinical management of cancer patients based on the liquid biomarker status. In recent years, more research has been done to investigate its potential utilization in patients with tumors from the spine. Herein, we review the liquid biomarkers that have been proposed in different spine malignancies including chordoma, chondrosarcoma, Ewing sarcoma, osteosarcoma, astrocytoma and ependymoma. We also discuss the wide window of opportunity to utilize these liquid biomarkers in diagnosis, treatment response, monitoring, and detection of minimal residual disease in patients with spinal tumors.

CONCLUSIONS

Liquid biomarkers, especially blood-derived circulating tumor DNA, has a promising clinical utility as they are disease-specific, minimally invasive, and the procedure is repeatable. Prospective studies with larger populations are needed to fully establish its use in the setting of spinal tumors.

Cancer phylogenetic inference using copy number alterations detected from DNA sequencing data

Cancer is an evolutionary process involving the accumulation of diverse somatic mutations and clonal evolution over time. Phylogenetic inference from samples obtained from an individual patient offers a powerful approach to unraveling the intricate evolutionary history of cancer and provides insights that can inform cancer treatment. Somatic copy number alterations (CNAs) are important in cancer evolution and are often used as markers, alone or with other somatic mutations, for phylogenetic inferences, particularly in low-coverage DNA sequencing data. Many phylogenetic inference methods using CNAs detected from bulk or single-cell DNA sequencing data have been developed over the years. However, there have been no systematic reviews on these methods. To summarize the state-of-the-art of the field and inform future development, this review presents a comprehensive survey on the major challenges in inference, different types of methods, and applications of these methods. The challenges are discussed from the aspects of input data, models of evolution, and inference algorithms. The different methods are grouped according to the markers used for inference and the types of the reconstructed trees. The applications include using phylogenetic inference to understand intra-tumor heterogeneity, metastasis, treatment resistance, and early cancer development. This review also sheds light on future directions of cancer phylogenetic inference using CNAs, including the improvement of scalability, the utilization of new types of data, and the development of more realistic models of evolution.

Microfluidic Nanoparticle Separation for Precision Medicine

A deeper understanding of disease heterogeneity highlights the urgent need for precision medicine. Microfluidics, with its unique advantages, such as high adjustability, diverse material selection, low cost, high processing efficiency, and minimal sample requirements, presents an ideal platform for precision medicine applications. As nanoparticles, both of biological origin and for therapeutic purposes, become increasingly important in precision medicine, microfluidic nanoparticle separation proves particularly advantageous for handling valuable samples in personalized medicine. This technology not only enhances detection, diagnosis, monitoring, and treatment accuracy, but also reduces invasiveness in medical procedures. This review summarizes the fundamentals of microfluidic nanoparticle separation techniques for precision medicine, starting with an examination of nanoparticle properties essential for separation and the core principles that guide various microfluidic methods. It then explores passive, active, and hybrid separation techniques, detailing their principles, structures, and applications. Furthermore, the review highlights their contributions to advancements in liquid biopsy and nanomedicine. Finally, it addresses existing challenges and envisions future development spurred by emerging technologies such as advanced materials science, 3D printing, and artificial intelligence. These interdisciplinary collaborations are anticipated to propel the platformization of microfluidic separation techniques, significantly expanding their potential in precision medicine.

FRET-Based Nanoprobe with Adaptive Background Suppression for Reliable Detection of ONOO-/ClO- in Whole Blood: Facilitating Monitoring of Sepsis Progression and Hemolytic Disorders

Abnormal fluctuations in blood biomarker levels serve as critical indicators of the disease. However, detecting endogenous substances in whole blood using fluorescent probes is challenging due to its complex composition. This challenge primarily arises from two factors: the high autofluorescence of whole blood and the intrinsic fluorescence of the probe, both contributing to significant background fluorescence in the detection system. To overcome these obstacles, we introduced a donor-acceptor "one-to-many" FRET-based sensing strategy integrated with blood autofluorescence suppression to design a multifunctional fluorescent nanoprobe. The donor effectively suppresses blood autofluorescence through the inner filter effect and efficiently quenches donor fluorescence by adjusting the acceptor-to-donor ratio, achieving a "zero" background in whole blood detection. Leveraging this excellent background fluorescence quenching effect, we successfully detected endogenous ONOO- and ClO- levels in whole blood samples from mice with sepsis or hemolytic diseases. Furthermore, we monitored the changes in the ONOO- and ClO- levels throughout the disease course, revealing a positive correlation between the ONOO- and ClO- concentrations and disease severity. This innovative sensing strategy for achieving a "zero" background in whole blood detection provides valuable insights for designing fluorescent probes to directly detect endogenous substances in whole blood.

Research Progress of Liquid Biopsy Based on DNA Methylation in Tumor Diagnosis and Treatment

Liquid biopsy has been gradually applied to the clinical diagnosis and treatment of tumors because of its non-invasive and real-time reflection of the tumor status, as well as the convenience of sample collection, which allows the detection of primary or metastatic malignant tumors and reflects the heterogeneity of the tumors. DNA methylation, which is a type of epigenetic modification, is essential in the progression of tumors. This review introduces the common DNA methylation analysis methods and discusses their advantages and disadvantages, focusing on the new progress of DNA methylation-based liquid biopsy in tumor diagnosis and treatment.

Genomic predictors of radiation response: recent progress towards personalized radiotherapy for brain metastases

Radiotherapy remains a key treatment modality for both primary and metastatic brain tumors. Significant technological advances in precision radiotherapy, such as stereotactic radiosurgery and intensity-modulated radiotherapy, have contributed to improved clinical outcomes. Notably, however, molecular genetics is not yet widely used to inform brain radiotherapy treatment. By comparison, genetic testing now plays a significant role in guiding targeted therapies and immunotherapies, particularly for brain metastases (BM) of lung cancer, breast cancer, and melanoma. Given increasing evidence of the importance of tumor genetics to radiation response, this may represent a currently under-utilized means of enhancing treatment outcomes. In addition, recent studies have shown potentially actionable mutations in BM which are not present in the primary tumor. Overall, this suggests that further investigation into the pathways mediating radiation response variability is warranted. Here, we provide an overview of key mechanisms implicated in BM radiation resistance, including intrinsic and acquired resistance and intratumoral heterogeneity. We then discuss advances in tumor sampling methods, such as a collection of cell-free DNA and RNA, as well as progress in genomic analysis. We further consider how these tools may be applied to provide personalized radiotherapy for BM, including patient stratification, detection of radiotoxicity, and use of radiosensitization agents. In addition, we describe recent developments in preclinical models of BM and consider their relevance to investigating radiation response. Given the increase in clinical trials evaluating the combination of radiotherapy and targeted therapies, as well as the rising incidence of BM, it is essential to develop genomically informed approaches to enhance radiation response.

Utilizing DNA Logic Device for Precise Detection of Circulating Tumor Cells via High Catalytic Activity Au Nanoparticle Anchoring

As medical advancements turn most cancers into manageable chronic diseases, new challenges arise in cancer recurrence monitoring. Detecting circulating tumor cells (CTCs) is crucial for monitoring cancer recurrence, but the current methods are cumbersome and costly. This study developed a new CTC detection system combining DNA aptamer recognition, hybridization chain reaction (HCR) technology, and DNA logic devices, enabling the one-step recognition of CTCs by identifying multiple membrane proteins. After catalytically active Au nanoparticles were attached through reduction synthesis in situ onto the DNA hybridization strands of the CTCs surface, a 3,3',5,5'-tetramethylbenzidine (TMB) colorimetric reaction was used to detect CTCs concentration via peroxidase-like catalysis. With this CTCs detection reporting system, we achieved an LOD of 4 cells/mL using an ultraviolet-visible (UV-vis) spectrophotometer. At certain concentrations, CTCs could even be detected visually without the need for an instrument. The development of this CTCs detection reporting system provided a convenient, reliable, and cost-effective detection strategy for widespread CTCs-based cancer recurrence monitoring.

Emerging role of circulating piRNAs in the diagnosis of heart transplant rejection

BACKGROUND

Liquid biopsy offers a potential alternative to decrease or eliminate endomyocardial biopsy for diagnosing allograft rejection. p-element-induced wimpy testis-interacting RNAs (piRNAs) are novel and promising disease biomarkers for their intrinsic characteristics such as stability in body fluids; however, their role in allograft rejection remains unexplored.

METHODS

A training set based on small RNA sequencing technology was performed to identify piRNAs in endomyocardial tissue (n = 8) and serum samples (n = 40) from patients following heart transplantation. A validation set of the potential piRNAs identified in the training study was conducted in an independent larger cohort for the detection of acute cellular rejection (ACR, n = 105) and antibody-mediated rejection (AMR, n = 61).

RESULTS

We identified 20,292 piRNAs in endomyocardial tissue and 24,602 piRNAs in serum samples from patients following heart transplantation. We identified 7 piRNAs with a coincident expression profile in both types of samples and potential capacity for the noninvasive detection of cardiac rejection. Validation in a large independent cohort demonstrated that a panel of these piRNAs showed excellent performance for detecting grade ≥2R ACR (area under the receiver operating characteristic curve [AUC] = 0.819; p < 0.0001) and grade 1R ACR (AUC = 0.721; p = 0.001). Furthermore, our piRNA panel showed a potential discrimination ability of pAMR2 (AUC = 0.967; p < 0.0001).

CONCLUSIONS

To the best of knowledge, this study is the first to report the presence of piRNAs in both endomyocardial tissue and serum samples of patients after heart transplant, including their association with allograft rejection events. We propose a novel piRNA panel for the detection of cardiac allograft rejection.

Exosome-Derived miRNAs in Liquid Biopsy for Lung Cancer

Exosome-derived microRNAs (miRNAs) are potential biomarkers for lung cancer detection and monitoring through liquid biopsy. These small, non-coding RNA molecules are found within exosomes, which are extracellular vesicles released from cells. Their stability in biofluids, such as blood, positions them as candidates for minimally invasive diagnostics. Multiple studies have shown that lung cancer patients exhibit distinct miRNA profiles compared to healthy individuals. This finding suggests that exosome-derived miRNAs could serve as valuable biomarkers for diagnosis, prognosis, and evaluating therapeutic responses. This review summarizes recent research on exosome-derived miRNAs in liquid biopsies, including blood, pleural effusion, and pleural lavage, as biomarkers for lung cancer, focusing on publications from the last five years.

LBFextract: Unveiling transcription factor dynamics from liquid biopsy data

Motivation

The analysis of circulating cell-free DNA (cfDNA) holds immense promise as a non-invasive diagnostic tool across various human conditions. However, extracting biological insights from cfDNA fragments entails navigating complex and diverse bioinformatics methods, encompassing not only DNA sequence variation, but also epigenetic characteristics like nucleosome footprints, fragment length, and methylation patterns.

Results

We introduce Liquid Biopsy Feature extract (LBFextract), a comprehensive package designed to streamline feature extraction from cfDNA sequencing data, with the aim of enhancing the reproducibility and comparability of liquid biopsy studies. LBFextract facilitates the integration of preprocessing and postprocessing steps through alignment fragment tags and a hook mechanism. It incorporates various methods, including coverage-based and fragment length-based approaches, alongside two novel feature extraction methods: an entropy-based method to infer TF activity from fragmentomics data and a technique to amplify signals from nucleosome dyads. Additionally, it implements a method to extract condition-specific differentially active TFs based on these features for biomarker discovery. We demonstrate the use of LBFextract for the subtype classification of advanced prostate cancer patients using coverage signals at transcription factor binding sites from cfDNA. We show that LBFextract can generate robust and interpretable features that can discriminate between different clinical groups. LBFextract is a versatile and user-friendly package that can facilitate the analysis and interpretation of liquid biopsy data.

Data and Code Availability and Implementation

LBFextract is freely accessible at https://github.com/Isy89/LBF. It is implemented in Python and compatible with Linux and Mac operating systems. Code and data to reproduce these analyses have been uploaded to 10.5281/zenodo.10964406.

Exosomal integrins in tumor progression, treatment and clinical prediction (Review)

Integrins are a large family of cell adhesion molecules involved in tumor cell differentiation, migration, proliferation and neovascularization. Tumor cell‑derived exosomes carry a large number of integrins, which are closely associated with tumor progression. As crucial mediators of intercellular communication, exosomal integrins have gained attention in the field of cancer biology. The present review examined the regulatory mechanisms of exosomal integrins in tumor cell proliferation, migration and invasion, and emphasized their notable roles in tumor initiation and progression. The potential of exosomal integrins as drug delivery systems in cancer treatment was explored. Additionally, the potential of exosomal integrins in clinical tumor prediction was considered, while summarizing their applications in diagnosis, prognosis assessment and treatment response prediction. Thus, the present review aimed to provide guidance and insights for future basic research and the clinical translation of exosomal integrins. The study of exosomal integrins is poised to offer new perspectives and methods for precise cancer treatment and clinical prediction.

Optimizing outcomes and personalizing care with targeted agents in advanced cholangiocarcinoma

Traditional chemotherapy and immunotherapy-based systemic treatments for locally advanced or metastatic cholangiocarcinoma have been associated with poor clinical outcomes driven partly by molecular heterogeneity promoting early treatment resistance and a higher toxicity profile associated with these regimens. Few patients are eligible for upfront surgical resection and clinical studies have been traditionally difficult to conduct due to the orphan nature of this disease. However, increasing use of genomic profiling in clinical practice have led to active investigations of aberrant albeit promising mechanistic therapeutic targets such as IDH-1, FGFRs, BRAFV600E, HER-2 and NTRK. This review article aims to highlight the complex genomic landscape of this difficult-to-treat disease, followed by a discussion of evidence-based biological mechanisms that can be actioned using targeted agents. We explore the clinical rationale behind a targeted therapeutic strategy, the role of liquid biopsies in guiding clinical decisions and future treatment pathways for cholangiocarcinoma management. We also discuss the challenges and opportunities originating from recent clinical trials evaluating targeted treatments and our own institutional experience at UCLH that have aimed to address some of these biological complexities and have translated into improved patient outcomes via effective molecularly driven patient selection strategies. We also provide perspectives on emerging novel, next generation targeted inhibitors overcoming treatment resistance to previous targeted agents with demonstrated clinical value in a challenging patient population.

Colocalization of Cancer-Associated Biomarkers on Single Extracellular Vesicles for Early Detection of Cancer

Detection of cancer early, when it is most treatable, remains a significant challenge because of the lack of diagnostic methods sufficiently sensitive to detect nascent tumors. Early-stage tumors are small relative to their tissue of origin, heterogeneous, and infrequently manifest in clinical symptoms. The detection of early-stage tumors is challenging given the lack of tumor-specific indicators (ie, protein biomarkers, circulating tumor DNA) to enable detection using a noninvasive diagnostic assay. To overcome these obstacles, we have developed a liquid biopsy assay that interrogates circulating extracellular vesicles (EVs) to detect tumor-specific biomarkers colocalized on the surface of individual EVs. We demonstrate the technical feasibility of this approach in human cancer cell line-derived EVs, where we show strong correlations between assay signal and cell line gene/protein expression for the ovarian cancer-associated biomarkers bone marrow stromal antigen-2, folate receptor-α, and mucin-1. Furthermore, we demonstrate that detecting distinct colocalized biomarkers on the surface of EVs significantly improves discrimination performance relative to single biomarker measurements. Using this approach, we observe promising discrimination of high-grade serous ovarian cancer versus benign ovarian masses and healthy women in a proof-of-concept clinical study.

NCI workshop on ctDNA in cancer treatment and clinical care

Detection of cell-free circulating tumor DNA (ctDNA) from solid tumors is a fast-evolving field with significant potential for improving patient treatment outcomes. The spectrum of applications for ctDNA assays is broad and includes very diverse intended uses that will require different strategies to demonstrate utility. On September 14-15, 2023, the National Cancer Institute held an in-person workshop in Rockville, MD titled "ctDNA in Cancer Treatment and Clinical Care." The goal of the workshop was to examine what is currently known and what needs to be determined for various ctDNA liquid biopsy use cases related to treatment and management of patients with solid tumors and to explore how the community can best assess the value of ctDNA assays and technology. Additionally, new approaches were presented that may show promise in the future. The information exchanged in this workshop will provide the community with a better understanding of this field and its potential to affect and benefit decision-making in the treatment of patients with solid tumors.

Omics-Enhanced Nanomedicine for Cancer Therapy

Cancer nanomedicine has emerged as a promising approach to overcome the limitations of conventional cancer therapies, offering enhanced efficacy and safety in cancer management. However, the inherent heterogeneity of tumors presents increasing challenges for the application of cancer nanomedicine in both diagnosis and treatment. This heterogeneity necessitates the integration of advanced and high-throughput analytical techniques to tailor nanomedicine strategies to individual tumor profiles. Omics technologies, encompassing genomics, epigenomics, transcriptomics, proteomics, metabolomics, and more, provide unparalleled insights into the molecular and cellular mechanisms underlying cancer. By dissecting tumor heterogeneity across multiple levels, these technologies offer robust support for the development of personalized and precise cancer nanomedicine strategies. In this review, the principles, techniques, and applications of key omics technologies are summarized. Especially, the synergistic integration of omics and nanomedicine in cancer therapy is explored, focusing on enhanced diagnostic accuracy, optimized therapeutic strategies and the assessment of nanomedicine-mediated biological responses. Moreover, this review addresses current challenges and outlines future directions in the field of omics-enhanced nanomedicine. By offering valuable insights and guidance, this review aims to advance the integration of omics with nanomedicine, ultimately driving improved diagnostic and therapeutic strategies for cancer.

Atomic force microscopy as a nanomechanical tool for cancer liquid biopsy

Liquid biopsies have been receiving tremendous attention for their potential to reshape cancer management. Though current studies of cancer liquid biopsy primarily focus on applying biochemical assays to characterize the genetic/molecular profiles of circulating tumor cells (CTCs) and their secondary products shed from tumor sites in bodily fluids, delineating the nanomechanical properties of tumor-associated materials in liquid biopsy specimens yields complementary insights into the biology of tumor dissemination and evolution. Particularly, atomic force microscopy (AFM) has become a standard and versatile toolbox for characterizing the mechanical properties of living biological systems at the micro/nanoscale, and AFM has been increasingly utilized to probe the nanomechanical properties of various tumor-derived analytes in liquid biopsies, including CTCs, tumor-associated cells, circulating tumor DNA (ctDNA) molecules, and extracellular vesicles (EVs), offering additional possibilities for understanding cancer pathogenesis from the perspective of mechanobiology. Herein, the applications of AFM in cancer liquid biopsy are summarized, and the challenges and future directions of AFM as a nanomechanical analysis tool in cancer liquid biopsy towards clinical utility are discussed and envisioned.

A Tandem-Locked Fluorescent Probe Activated by Hypoxia and a Viscous Environment for Precise Intraoperative Imaging of Tumor and Instant Assessment of Ferroptosis-Mediated Therapy

Noninvasive fluorescence detection of tumor-associated biomarker dynamics provides immediate insights into tumor biology, which are essential for assessing the efficacy of therapeutic interventions, adapting treatment strategies, and achieving personalized diagnosis and therapy evaluation. However, due to the absence of a single biomarker that effectively reflects tumor development and progression, the currently available optical diagnostic agents that rely on "always-on" or single pathological activation frequently show nonspecific fluorescence responses and limited tumor accumulation, which inevitably compromises the accuracy and reliability of tumor imaging. Herein, based on intramolecular charge transfer (ICT) and twisted intramolecular charge-transfer (TICT) hybrid mechanisms, we report a tandem-locked probe, NTVI-Biotin, for simultaneously specific imaging-guided tumor resection and ferroptosis-mediated tumor ablation evaluation under the coactivation of nitro reductase (NTR)/viscosity. The dual-stimulus-responsive design strategy ensures that NTVI-Biotin exclusively activates near-infrared (NIR) fluorescence signals upon interaction with both NTR and elevated viscosity levels through triggering ICT on while inhibiting the TICT process. Meanwhile, functionalization with a tumor-targeting hydrophilic biotin-poly(ethylene glycol) moiety enhances tumor accumulation. The probe's dual-response and tumor-targeting design minimizes nonspecific tissue activation, allowing for precise tumor identification and lesion removal with a superior tumor-to-normal tissue (T/N > 6) ratio. More importantly, NTVI-Biotin was capable of evaluating ferroptosis-mediated chemotherapeutics by real-time monitoring of the alternations of NTR/viscosity levels. The results reveal that the increased tumor signals of NTVI-Biotin following the combination of ferroptosis and chemotherapy correlate well with the tumor growth inhibition, demonstrating the potential of NTVI-Biotin to assess therapeutic efficacy.

Opportunities and challenges of using circulating tumor DNA to predict lung cancer immunotherapy efficacy

Immune checkpoint inhibitors (ICIs), particularly anti-programmed death 1 (PD-1)/ programmed death ligand 1 (PD-L1) antibodies, have led to significant progress in lung cancer treatment. However, only a minority of patients have responses to these therapies. Detecting peripheral blood of circulating tumor DNA (ctDNA) allows minimally invasive diagnosis, characterization, and monitoring of lung cancer. ctDNA has potential to be a prognostic biomarker and a predictor of the response to ICI therapy since it can indicate the genomic status and tumor burden. Recent studies on lung cancer have shown that pretreatment ctDNA analysis can detect residual proliferative disease in the adjuvant immunotherapy setting and evaluate tumor burden in patients with metastatic disease. Early ctDNA dynamics can not only predict the clinical outcome of ICI therapy but also help distinguish between pseudoprogression and real progression. Furthermore, in addition to quantitative assessment, ctDNA can also detect genetic predictors of response to ICI therapy. However, barriers still exist in the application of ctDNA analysis in clinical lung cancer treatment. The predictive value of ctDNA in lung cancer immunotherapy requires further identification and resolution of these challenges. This review aims to summarize the existing data of ctDNA analysis in patients receiving immunotherapy for lung cancer, understand the limitations of clinical treatment, and discuss future research directions.

Neoadjuvant Chemotherapy Shortens the cfDNA Telomere Length in Breast Cancer Patients

Introduction: Cancer is a genetic disease that affects people worldwide, and breast cancer is the most common cancer in women. Studies have been conducted on molecular parameters to predict tumor behavior and develop therapeutic strategies. Telomeres, which are at the end of chromosomes, have been studied for their relationship with breast cancer, but more research is needed to understand their role in the disease. Circulating-free DNA (cfDNA) is DNA that is free in the bloodstream and is considered a promising target for early cancer detection, treatment response monitoring, and prognosis assessment. This study is aimed at comparing cfDNA telomere length of breast cancer patients and healthy individuals and analyzing the impact of neoadjuvant chemotherapy on telomere length in cfDNA. Materials and Methods: Blood samples were collected from 33 breast cancer patients undergoing neoadjuvant chemotherapy before and after treatment. The quantitative PCR method is used to measure the average telomere lengths. Results: This study found that the telomere length of cfDNA in breast cancer patients before and after treatment is significantly shorter than in the control group. Neoadjuvant chemotherapy is found to shorten the cfDNA telomere length, especially in the treatment-responsive group. Conclusion: Our study suggests that telomere length in cfDNA may be a useful biomarker for predicting therapy response and possible reoccurrence of the disease in breast cancer patients.

Nucleic acid detection with single-base specificity integrating isothermal amplification and light-up aptamer probes

We report a novel platform for label-free nucleic acid detection using isothermal amplification and light-up aptamer probes. This assay converts double-stranded amplicons into single-stranded targets to enable sequence-specific hybridization with split dapoxyl aptamer probes, offering attomolar sensitivity and single-base specificity.

Recent advances in fluorescent probes for ATP imaging

Adenosine-5'-triphosphate (ATP) is a critical biological molecule that functions as the primary energy currency within cells. ATP synthesis occurs in the mitochondria, and variations in its concentration can significantly influence mitochondrial and cellular performance. Prior studies have established a link between ATP levels and a variety of diseases, such as cancer, neurodegenerative conditions, ischemia, and hypoglycemia. Consequently, researchers have developed many fluorescent probes for ATP detection, recognizing the importance of monitoring intracellular ATP levels to understand cellular processes. These probes have been effectively utilized for visualizing ATP in living cells and biological samples. In this comprehensive review, we categorize fluorescent sensors developed in the last five years for ATP detection. We base our classification on fluorophores, structure, multi-response channels, and application. We also evaluate the challenges and potential for advancing new generations of fluorescence imaging probes for monitoring ATP in living cells. We hope this summary motivates researchers to design innovative and effective probes tailored to ATP sensing. We foresee imminent progress in the development of highly sophisticated ATP probes.

A scenario-drafting study to explore potential future implementation pathways of circulating tumor DNA testing in oncology

Circulating tumor DNA (ctDNA) detection has multiple promising applications in oncology, but the road toward implementation in clinical practice is unclear. We aimed to support the implementation process by exploring potential future pathways of ctDNA testing. To do so, we studied four ctDNA-testing applications in two cancer types and elicited opinions from 30 ctDNA experts in the Netherlands. Our results showed that the current available evidence differed per application and cancer type. Tumor profiling and monitoring treatment response were found most likely to be implemented in non-small cell lung cancer (NSCLC) within 5 years. For colorectal cancer, applications of ctDNA testing were found to be at an early stage in the implementation process. Demonstrating clinical utility was found a key aspect for successful implementation, but there was no consensus regarding the evidence requirements. The next step toward implementation is to define how clinical utility of biomarkers should be evaluated. Finally, these data indicate that specific challenges for each clinical application and tumor type should be appropriately addressed in a deliberative process involving all stakeholders to ensure implementation of ctDNA testing and timely access for patients.

Circulating tumor DNA methylation detection as biomarker and its application in tumor liquid biopsy: advances and challenges

Circulating tumor DNA (ctDNA) methylation, an innovative liquid biopsy biomarker, has emerged as a promising tool in early cancer diagnosis, monitoring, and prognosis prediction. As a noninvasive approach, liquid biopsy overcomes the limitations of traditional tissue biopsy. Among various biomarkers, ctDNA methylation has garnered significant attention due to its high specificity and early detection capability across diverse cancer types. Despite its immense potential, the clinical application of ctDNA methylation faces substantial challenges pertaining to sensitivity, specificity, and standardization. In this review, we begin by introducing the basic biology and common detection techniques of ctDNA methylation. We then explore recent advancements and the challenges faced in the clinical application of ctDNA methylation in liquid biopsies. This includes progress in early screening and diagnosis, identification of clinical molecular subtypes, monitoring of recurrence and minimal residual disease (MRD), prediction of treatment response and prognosis, assessment of tumor burden, and determination of tissue origin. Finally, we discuss the future perspectives and challenges of ctDNA methylation detection in clinical applications. This comprehensive overview underscores the vital role of ctDNA methylation in enhancing cancer diagnostic accuracy, personalizing treatments, and effectively monitoring disease progression, providing valuable insights for future research and clinical practice.

A drug-mediated organic electrochemical transistor for robustly reusable biosensors

Reusable point-of-care biosensors offer a cost-effective solution for serial biomarker monitoring, addressing the critical demand for tumour treatments and recurrence diagnosis. However, their realization has been limited by the contradictory requirements of robust reusability and high sensing capability to multiple interactions among transducer surface, sensing probes and target analytes. Here we propose a drug-mediated organic electrochemical transistor as a robust, reusable epidermal growth factor receptor sensor with striking sensitivity and selectivity. By electrostatically adsorbing protonated gefitinib onto poly(3,4-ethylenedioxythiophene):polystyrene sulfonate and leveraging its strong binding to the epidermal growth factor receptor target, the device operates with a unique refresh-in-sensing mechanism. It not only yields an ultralow limit-of-detection concentration down to 5.74 fg ml-1 for epidermal growth factor receptor but, more importantly, also produces an unprecedented regeneration cycle exceeding 200. We further validate the potential of our devices for easy-to-use biomedical applications by creating an 8 × 12 diagnostic drug-mediated organic electrochemical transistor array with excellent uniformity to clinical blood samples.

Roles and Applications of Circulating Tumor-Derived RNAs in Sarcoma Patients: A Systematic Review

Sarcomas are a heterogeneous group of malignancies with a high mortality rate. Detection of circulating tumor-derived material, such as circulating RNA in the peripheral blood of patients, has shown to be useful in diagnosis, prediction of prognosis and disease monitoring in several malignancies. This systematic review aims to probe the existing methods for detecting circulating tumor-derived RNAs from patients affected by sarcoma and their possible clinical application. A systematic review of the literature indexed in PubMed was performed. Each article had to analyze circulating RNA in human specimens obtained from liquid biopsies of patients affected by sarcoma. A total of 26 articles were included. We evaluated 1381 patients; 72% were affected by bone sarcoma and 28% by soft tissue sarcoma. By PCR-based methods, all the studies investigated circulating tumor RNA, mostly in the peripheral blood. Nearly half of the authors investigated the tumor expression and/or release of miRNA (42%). Several authors pointed out that circulating tumor-derived RNA has proven to have potential application in a clinical setting for sarcomas. To the best of our knowledge, this is the first review in the literature to attempt to put together data specifically on ctRNA in patients affected by sarcoma.

Detection of EGFR mutations in patients with suspected lung cancer using paired tissue-plasma testing: a prospective comparative study with plasma ddPCR assay

Detecting EGFR mutations in plasma using droplet digital PCR (ddPCR) assay offers a promising diagnostic tool for lung cancer patients. The performance of plasma-based ddPCR assay relative to traditional EGFR mutation testing in tissue biopsies among Asian patients with suspected lung cancer remains underexplored. Consecutive patients admitted for diagnostic workup for suspected lung cancer were recruited. Peripheral blood samples were collected on the same day of tissue biopsies. Tissue samples were subjected to EGFR mutation analysis via real-time PCR, whereas plasma samples were processed for ddPCR assay to evaluate for EGFR mutation status. The tissue re-biopsy rate was 43.8% while 0.7% of patients failed blood taking. Despite repeat biopsy, 15.2% of patients could not achieve histological diagnosis. Of the 202 patients newly diagnosed with lung cancer, EGFR mutations were detected in 13.4% of plasma samples, compared to 44.3% in tissue samples. Plasma ddPCR for EGFR mutations detection were barely detectable in stages I and II non-small cell lung cancer (NSCLC), but the sensitivity was 25.0%, 56.3%, and 75.0% in stages III, IVA, and IVB NSCLC, respectively. Plasma EGFR mutations were highly specific among all stages of lung cancer. Concordance rates of plasma ddPCR assay also rose with more advanced stages, recorded at 41.9% for stages I and II, 71.9% for stage III, 86.3% for stage IV. In stage IV lung cancer, the false negative rate for the plasma ddPCR assay was 34.4%, whereas that for the tissue testing was 19.2% due to insufficient tissue samples. Plasma-based EGFR genotyping using ddPCR is a non-invasive method that offers early diagnosis and serves as a valuable adjunct to tissue-based testing for patients with advanced-stage lung cancer. However, its usefulness is limited in the context of early-stage lung cancer, indicating a need for further research to improve its accuracy in these patients.

LC-MS/MS analysis reveals plasma protein signatures associated with lymph node metastasis in colorectal cancer

Objectives

Colorectal cancer (CRC) is a major global health concern, ranking as the third most common cancer and the fourth leading cause of cancer-related deaths worldwide. Currently, the diagnostic accuracy of Lymph node metastasis (LNM) is currently unsatisfactory. Therefore, there is an urgent need to develop a reliable tool that can accurately predict lymph node metastasis (LNM) in patients diagnosed with CRC.

Methods

We conducted an extensive proteomics investigation aimed at examining lymph node metastasis (LNM) in individuals diagnosed with colorectal cancer (CRC). In the discovery stage, employing a mass spectrometry-based proteomic approach, we analyzed a cohort of 60 colorectal cancer patients (NM=30, LNM=30), identifying distinct molecular profiles that differentiate patients with and without lymph node metastasis (LNM). Subsequently, we validated the protein classifier associated with lymph node metastasis.

Results

We elucidated a combinatorial predictive protein biomarker that can distinguish patients with and without lymph node metastasis by LC-MS/MS. The classifier achieved an area under the curve (AUC) of 0.892 (95% CI, 0.842-0.941), while in the testing cohort, it attained an AUC of 0.929 (95% CI, 0.824-1.000). Furthermore, the four protein markers demonstrated an AUC of 0.84 (95% CI, 0.783-0.890) in the validation cohort. Additionally, we categorized patients into three types based on immunophenotyping. Type 1 primarily consisted of patients with negative lymph node metastasis (NM), characterized by immune cells such as NK cells, CD4 T effector memory cells, and memory B cells. Type 2 mainly included patients with positive lymph node metastasis (LNM), characterized by immune cells such as mesangial cells, epithelial cells, and mononuclear cells. In Type 1, a prominent upregulation observed in immune inflammation, as well as in glucose and lipid metabolism. In Type 2, significant upregulation was evident in pathways such as pyrimidine metabolism and cell cycle regulation. The findings of this study suggest that immune mechanisms may exert a pivotal role in the process of lymph node metastasis in CRC.

Conclusions

Here, we present plasma protein signatures associated with lymph node metastasis in colorectal cancer (CRC). However, further validation across multiple centers is necessary to generalize these findings.

Aggregation-Induced Emission Luminogen: Role in Biopsy for Precision Medicine

Biopsy, including tissue and liquid biopsy, offers comprehensive and real-time physiological and pathological information for disease detection, diagnosis, and monitoring. Fluorescent probes are frequently selected to obtain adequate information on pathological processes in a rapid and minimally invasive manner based on their advantages for biopsy. However, conventional fluorescent probes have been found to show aggregation-caused quenching (ACQ) properties, impeding greater progresses in this area. Since the discovery of aggregation-induced emission luminogen (AIEgen) have promoted rapid advancements in molecular bionanomaterials owing to their unique properties, including high quantum yield (QY) and signal-to-noise ratio (SNR), etc. This review seeks to present the latest advances in AIEgen-based biofluorescent probes for biopsy in real or artificial samples, and also the key properties of these AIE probes. This review is divided into: (i) tissue biopsy based on smart AIEgens, (ii) blood sample biopsy based on smart AIEgens, (iii) urine sample biopsy based on smart AIEgens, (iv) saliva sample biopsy based on smart AIEgens, (v) biopsy of other liquid samples based on smart AIEgens, and (vi) perspectives and conclusion. This review could provide additional guidance to motivate interest and bolster more innovative ideas for further exploring the applications of various smart AIEgens in precision medicine.

Development and validation of a multi-marker liquid bead array assay for the simultaneous detection of PIK3CA and ESR1 hotspot mutations in single circulating tumor cells (CTCs)

Background

PIK3CA and ESR1 mutations are associated with progression and therapy resistance in metastatic breast cancer (MBC). CTCs are highly heterogeneous and their analysis at single cell level can provide unique information for mutational profiling and the existence of different sub-clones related to tumor progression. We have developed a novel multi-marker liquid bead array assay based on combination of an enzymatic mutation enrichment method, multiplex PCR-based assay, and liquid bead array technology for the simultaneous detection of PIK3CA and ESR1 hotspot mutations in liquid biopsy samples. We focus on single CTCs, however the assay can be used for bulk CTC and ctDNA analysis.

Materials and methods

Single CTCs were isolated from an ER+/HER2+ MBC patient from CellSearch® cartridges using the VyCAP Puncher System and subjected to whole genome amplification followed by nuclease-assisted minor-allele enrichment with probe-overlap (NaME-PrO) enrichment. The assay was validated for analytical sensitivity and specificity for the simultaneous detection of PIK3CA (E545K, E542K, H1047R, H1047L) and ESR1 (Y537S, Y537C, Y537N, D538G, L536H) mutations in single CTCs, while its clinical performance was evaluated on 22 single CTCs and three single white blood cells (WBCs).

Results

The developed multi-marker liquid bead array assay is novel, highly specific and sensitive for both mutation panels. The assay can reliably detect mutation-allelic-frequencies (MAFs) as low as 0.1 %. The presence of PIK3CA and ESR1 mutations was detected in 13.6 % and 72.7 % of single CTCs, respectively. The developed assay is sample-saving since it requires only 2 μL of amplified DNA to check for nine hotspot PIK3CA and ESR1 mutations in a single cell. The developed liquid bead array assay (Luminex, US), based on a 96 microwell plate format, enables the simultaneous analysis of 96 single cells.

Conclusions

The developed novel multi-marker liquid bead array assay for the simultaneous detection of PIK3CA and ESR1 hotspot mutations in single CTCs is highly specific, highly sensitive, high-throughput, and sample-, cost-, and time-saving. This multi-marker liquid bead array assay can be extended to detect up to 100 mutations in many genes at once and can be applied for bulk CTC and ctDNA analysis.

The detection, biological function, and liquid biopsy application of extracellular vesicle-associated DNA

Cell-derived extracellular vesicles (EVs), which carry diverse biomolecules such as nucleic acids, proteins, metabolites, and lipids reflecting their cell of origin, are released under both physiological and pathological conditions. EVs have been demonstrated to mediate cell-to-cell communication and serve as biomarkers. EV-associated DNA (EV-DNA) comprises genomic and mitochondrial DNA (i.e., gDNA and mtDNA) fragments. Some studies have revealed that EV-DNA can represent the full nuclear genome and mitochondrial genome of parental cells. Furthermore, DNA fragments loaded into EVs are stable and can be transferred to recipient cells to regulate their biological functions. In this review, we summarized and discussed EV-DNA research advances with an emphasis on EV-DNA detection at the population-EV and single-EV levels, gene transfer-associated biological functions, and clinical applications as biomarkers for disease liquid biopsy. We hope that this review will provide potential directions or guidance for future EV-DNA investigations.

Amplifying mutational profiling of extracellular vesicle mRNA with SCOPE

Sequencing of messenger RNA (mRNA) found in extracellular vesicles (EVs) in liquid biopsies can provide clinical information such as somatic mutations, resistance profiles and tumor recurrence. Despite this, EV mRNA remains underused due to its low abundance in liquid biopsies, and large sample volumes or specialized techniques for analysis are required. Here we introduce Self-amplified and CRISPR-aided Operation to Profile EVs (SCOPE), a platform for EV mRNA detection. SCOPE leverages CRISPR-mediated recognition of target RNA using Cas13 to initiate replication and signal amplification, achieving a sub-attomolar detection limit while maintaining single-nucleotide resolution. As a proof of concept, we designed probes for key mutations in KRAS, BRAF, EGFR and IDH1 genes, optimized protocols for single-pot assays and implemented an automated device for multi-sample detection. We validated SCOPE's ability to detect early-stage lung cancer in animal models, monitored tumor mutational burden in patients with colorectal cancer and stratified patients with glioblastoma. SCOPE can expedite readouts, augmenting the clinical use of EVs in precision oncology.

Potential Use of Extracellular Vesicles for the HER2 Status Assessment in Breast Cancer Patients

Human epithelial growth factor receptor 2 (HER2)-targeted therapies are effective in patients with HER2-positive breast cancer. Recent advances have shown that HER2-targeted therapies can also be of benefit when treating tumors expressing low levels of HER2, highlighting the importance of identifying the HER2-low subgroup. This clinical trend has opened new therapeutic avenues for patients who were previously ineligible for HER2-targeted therapies. Thus, the development of new diagnostic methods for real-time HER2 profiling is crucial for accurately tailoring the treatment for these patients. We hypothesized that tumor-derived extracellular vesicles (TEVs) could reflect the HER2 profiles of primary tumors and potentially serve as diagnostic tools for HER2 status. This approach was validated using six breast cancer cell lines, which confirmed that the TEVs accurately reflected the HER2 profiles of the tumor cells. TEVs were isolated using an immunoaffinity method, and copy number variation (CNV) in the ERBB2/EIF2C ratio was assessed using droplet digital PCR of DNA from these vesicles. Clinical validation using plasma samples from 33 breast cancer patients further reinforced the diagnostic potential of our method. Pearson's correlation coefficient analysis of the flow cytometry results demonstrated that TEVs reflected HER2 expression in primary cells. To distinguish between HER2-negative and HER2-low patients, the area under the curve (AUC) of the ROC curve in our method was 0.796, with a sensitivity of 53.8% and a specificity of 100%. These findings suggest the clinical utility of extracellular vesicles derived from plasma and emphasize the need for further research to distinguish HER2-negative from HER2-low patients.