Cell-free DNA as a biomarker in cancer

Gene expression profiling for the diagnosis of male breast cancer

BACKGROUND

Male breast cancer (MBC) is a rare malignancy, but its global incidence has shown a notable increase in recent decades. Factors such as limited health literacy, inadequate health education, and reluctance to seek medical attention contribute to the late-stage diagnosis of most MBC patients. Consequently, there is an urgent need for a highly specific and sensitive diagnostic approach to MBC.

METHODS

This retrospective study enrolled 20 patients with 30 surgical or biopsy MBC specimens from August 2020 to August 2023. The 90-gene expression assay was performed to determine the tissue of origin. Predicted tumor types were then compared to the reference diagnosis for accuracy calculation. The differentially expressed genes were identified between male and female breast cancer.

RESULT

The 90-gene expression assay demonstrated an overall accuracy of 96.7% (29/30) when compared with the pathological diagnosis. For primary, lymph node metastatic, and distant metastatic tumors, the accuracies were 100% (15/15), 90.9% (10/11), and 100% (4/4), respectively. Five genes (RPS4Y1, PI15, AZGP1, PRRX1, and AGR2) were up-regulated, and six (XIST, PIGR, SFRP1, PLA2G2A, S100A2, and CHI3L1) were down-regulated in MBC.

CONCLUSION

Our findings highlight the promising performance of the 90-gene expression assay in accurately identifying the tumor origin in MBC. Incorporating this assay into pathological diagnoses has the potential to empower oncologists with precision treatment options, ultimately enhancing the care and outcomes for patients with MBC.

A pan-cancer analysis of the oncogenic role of N-acetyltransferase 8 like in human cancer

BACKGROUND

N-Acetyltransferase 8 Like (NAT8L) inhibits natural killer (NK)/T-cell cytotoxicity by impairing the formation of the immunological synapse via N-acetylaspartate (NAA). Existing research has predominantly focused on the metabolic functions of NAT8L, particularly in adipose tissues and myelination in the brain. However, in contrast to other N-acetyltransferases such as NAT1 and NAT2, the role of NAT8L in cancer has been less extensively studied. In this study, we conducted a comprehensive pan-cancer analysis to investigate the carcinogenic role of NAT8L in human cancers.

METHODS

We utilized the standardized TCGA pan-cancer dataset to analyze differential expression, clinical prognosis, gene mutation, immune infiltration, epigenetic modification, tumor stemness, and heterogeneity. Additionally, we evaluated the sensitivity of NAT8L to small molecule drugs using the GDSC and CTRP databases.

RESULTS

In this study, we identified that NAT8L expression was upregulated in 6 cancers and downregulated in 12 compared to normal tissues. We analyzed its prognostic value in 5 tumor types (KIRP, COAD, COADREAD, GBMLGG, LUSC) and found correlations with overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI). Furthermore, NAT8L expression was significantly correlated with levels of most immune checkpoints, immunomodulators, and immune cell infiltration. The mutation frequencies for bladder cancer (BLCA), glioblastoma multiforme and glioma (GBMLGG), lower-grade glioma (LGG), and KIRP were 1.2%, 0.9%, 0.8%, and 0.4%, respectively.

CONCLUSION

Our findings suggest that NAT8L may serve as a potential prognostic marker and therapeutic target across a variety of cancers, particularly in KIRP, COAD, COADREAD, GBMLGG, and lung squamous cell carcinoma (LUSC).

Diagnostic Utility of a 90-Gene Expression Assay (Canhelp-Origin) for Patients with Metastatic Cancer with an Unclear or Unknown Diagnosis

BACKGROUND

Metastatic cancers with unclear or unknown origins pose significant challenges in diagnosis and management, frequently leading to suboptimal outcomes. Studies have demonstrated that a 90-gene expression assay is effective in predicting the primary origin and guiding the site-specific therapy to improve prognosis. This study aimed to evaluate the clinical effectiveness of a 90-gene expression assay in patients with unclear or unknown diagnoses.

METHODS

The study encompassed patients for whom a 90-gene expression assay was requested as part of standard care. Data on patient demographics, tumor characteristics, and clinical history were collected. The assay's performance was evaluated by comparing its predicted tumor type with the final histopathological diagnosis.

RESULTS

Among 303 cases analyzed, a 90-gene expression assay successfully identified a molecular-based tumor type for 295 (97.4%) patients. Comparison with histopathological diagnosis revealed an overall agreement of 88.5% (170/192). In patients with a single suspected primary site (n = 140), the assay confirmed the suspected diagnosis in 90.7% of cases. For those with a differential diagnosis (n = 52), the assay narrowed down the possibilities in 82.7% of cases. Moreover, in cases where the histopathology report indicated cancer of unknown primary (n = 103), the assay offered a molecular tumor type prediction with potential clinical significance.

CONCLUSIONS

This study demonstrates the significant impact of a 90-gene expression assay on diagnosis and potential treatment selection for difficult-to-diagnose patients, highlighting its clinical value as a standardized molecular approach to streamline further diagnostic testing for patients with metastatic cancer of unclear or unknown origin. Further prospective study is required to assess whether employing molecular diagnostic classifiers enhances clinical outcomes in these patients.

Liquid Biopsies for Monitoring Medulloblastoma: Circulating Tumor DNA as a Biomarker for Disease Progression and Treatment Response

Pediatric brain tumors, including medulloblastoma (MB), represent a significant challenge in clinical oncology. Early diagnosis, accurate monitoring of therapeutic response, and the detection of minimal residual disease (MRD) are crucial for improving outcomes in these patients. This review aims to explore recent advancements in liquid biopsy techniques for monitoring pediatric brain tumors, with a specific focus on medulloblastoma. The primary research question is how liquid biopsy techniques can be effectively utilized for these purposes. Liquid biopsies, particularly the analysis of circulating tumor DNA (ctDNA) in cerebrospinal fluid (CSF), are investigated as promising noninvasive tools. This comprehensive review examines the components of liquid biopsies, including ctDNA, cell-free DNA (cfDNA), and microRNA (miRNA). Their applications in diagnosis, prognosis, and MRD assessment are critically assessed. The review also discusses the role of liquid biopsies in categorizing medulloblastoma subgroups, risk stratification, and the identification of therapeutic targets. Liquid biopsies have shown promising applications in the pediatric brain tumor field, particularly in medulloblastoma. They offer noninvasive means of diagnosis, monitoring treatment response, and detecting MRD. These biopsies have played a pivotal role in subgroup classification and risk stratification of medulloblastoma patients, aiding in the identification of therapeutic targets. However, challenges related to sensitivity and specificity are noted. In conclusion, this review highlights the growing importance of liquid biopsies, specifically ctDNA analysis in CSF, in pediatric brain tumor management, with a primary focus on medulloblastoma. Liquid biopsies have the potential to revolutionize patient care by enabling early diagnosis, accurate monitoring, and MRD detection. Nevertheless, further research is essential to validate their clinical utility fully. The evolving landscape of liquid biopsy applications underscores their promise in improving outcomes for pediatric brain tumor patients.

[Individualized precision medicine]

Spectacular advances have been made in personalized medicine , which has rapidly revolutionized our traditional understanding of disease diagnosis and treatment. Molecular testing of tissue and liquid samples using next generation sequencing has developed into a key technology in this scenario. It can be used for both the determination of biomarkers for diagnostic, prognostic and predictive purposes, as well as the possible improvement of treatment outcome through the use of targeted therapies and the avoidance of therapies in the event of special resistance situations. In addition to drugs that have already been approved, which among other things intervene in cellular DNA repair, many new drugs have been developed and are in clinical testing. Furthermore, new possibilities in molecular imaging have dramatically expanded our understanding of tumor spread and created new approaches for targeted therapies.

Circulating Cell-Free Nucleic Acids as Biomarkers for Diagnosis and Prognosis of Pancreatic Cancer

A lack of reliable early diagnostic tools represents a major challenge in the management of pancreatic cancer (PCa), as the disease is often only identified after it reaches an advanced stage. This highlights the urgent need to identify biomarkers that can be used for the early detection, staging, treatment monitoring, and prognosis of PCa. A novel approach called liquid biopsy has emerged in recent years, which is a less- or non-invasive procedure since it focuses on plasmatic biomarkers such as DNA and RNA. In the blood of patients with cancer, circulating tumor cells (CTCs) and cell-free nucleic acids (cfNAs) have been identified such as DNA, mRNA, and non-coding RNA (miRNA and lncRNA). The presence of these molecules encouraged researchers to investigate their potential as biomarkers. In this article, we focused on circulating cfNAs as plasmatic biomarkers of PCa and analyzed their advantages compared to traditional biopsy methods.

Medulloblastoma: From TP53 Mutations to Molecular Classification and Liquid Biopsy

A recent paradigm shift in the diagnostics of medulloblastoma allowed the distinction of four major groups defined by genetic data rather than histology. This new molecular classification correlates better with prognosis and will allow for the better clinical management of therapies targeting druggable mutations, but also offer a new combination of monitoring tumor development in real-time and treatment response by sequential liquid biopsy. This review highlights recent developments after a century of milestones in neurosurgery and radio- and chemotherapy, but also controversial theories on the cell of origin, animal models, and the use of liquid biopsy.

Non-steroidal anti-inflammatory drugs and biomarkers: A new paradigm in colorectal cancer

Colorectal cancer is a sporadic, hereditary, or familial based disease in its origin, caused due to diverse set of mutations in large intestinal epithelial cells. Colorectal cancer (CRC) is a common and deadly disease that accounts for the 4^th worldwide highly variable malignancy. For the early detection of CRC, the most common predictive biomarker found endogenously are KRAS and ctDNA/cfDNA along with SEPT9 methylated DNA. Early detection and screening for CRC are necessary and multiple methods can be employed to screen and perform early diagnosis of CRC. Colonoscopy, an invasive method is most prevalent for diagnosing CRC or confirming the positive result as compared to other screening methods whereas several non-invasive techniques such as molecular analysis of breath, urine, blood, and stool can also be performed for early detection. Interestingly, widely used medicines known as non-steroidal anti-inflammatory drugs (NSAIDs) to reduce pain and inflammation have reported chemopreventive impact on gastrointestinal malignancies, especially CRC in several epidemiological and preclinical types of research. NSAID acts by inhibiting two cyclooxygenase enzymes, thereby preventing the synthesis of prostaglandins (PGs) and causing NSAID-induced apoptosis and growth inhibition in CRC cells. This review paper majorly focuses on the diversity of natural and synthetic biomarkers and various techniques for the early detection of CRC. An approach toward current advancement in CRC detection techniques and the role of NSAIDs in CRC chemoprevention has been explored systematically. Several prominent governing mechanisms of the anti-cancer effects of NSAIDs and their synergistic effect with statins for an effective chemopreventive measure have also been discussed in this review paper.

Liquid biopsy and glioblastoma

Glioblastoma is the most common and malignant primary brain tumor. Despite a century of research efforts, the survival of patients has not significantly improved. Currently, diagnosis is based on neuroimaging techniques followed by histopathological and molecular analysis of resected or biopsied tissue. A recent paradigm shift in diagnostics ranks the molecular analysis of tissue samples as the new gold standard over classical histopathology, thus correlating better with the biological behavior of glioblastoma and clinical prediction, especially when a tumor lacks the typical hallmarks for glioblastoma. Liquid biopsy aims to detect and quantify tumor-derived content, such as nucleic acids (DNA/RNA), circulating tumor cells (CTCs), or extracellular vesicles (EVs) in biofluids, mainly blood, cerebrospinal fluid (CSF), or urine. Liquid biopsy has the potential to overcome the limitations of both neuroimaging and tissue-based methods to identify early recurrence and to differentiate tumor progression from pseudoprogression, without the risks of repeated surgical biopsies. This review highlights the origins and time-frame of liquid biopsy in glioblastoma and points to recent developments, limitations, and challenges of adding liquid biopsy to support the clinical management of glioblastoma patients.

Cell-Free DNA Sequencing Reveals Gene Variants in DNA Damage Repair Genes Associated with Prognosis of Prostate Cancer Patients

In the present study, we further analyzed the data obtained in our previous study, where we investigated the cell-free DNA (cfDNA) of 34 progressive prostate cancer patients via targeted sequencing. Here, we studied the occurrence and prognostic impact of sequence variants according to their clinical pathological significance (CPS) or their functional impact (FI) in 23 DNA damage repair (DDR) genes with a focus on the ATM serine/threonine kinase gene (ATM). All patients had at least one DDR gene with a CPS or FI variant. Kaplan-Meier analysis indicated that the group with a higher number of CPS variants in DDR genes had a shorter time to treatment change (TTC) compared to the group with a lower number of CPS variants (p = 0.038). Analysis of each DDR gene revealed that CPS variants in the ATM gene and FI variants in the nibrin (NBN) gene showed a shorter TTC (p = 0.034 and p = 0.042). In addition, patients with CPS variants in the ATM gene had shorter overall survival (OS; p = 0.022) and disease-specific survival (DSS; p = 0.010) than patients without these variants. Interestingly, patients with CPS variants in seven DDR genes possessed a better OS (p = 0.008) and DSS (p = 0.009), and patients with FI variants in four DDR genes showed a better OS (p = 0.007) and DSS (p = 0.008). Together, these findings demonstrated that the analysis of cfDNA for gene variants in DDR genes provides prognostic information that may be helpful for future temporal and targeted treatment decisions for advanced PCa patients.

Liquid biopsy for monitoring medulloblastoma

Despite recent progress in molecular diagnostics defining four distinct medulloblastoma groups, the clinical management of these malignant childhood tumors of the cerebellum remains challenging. After surgical removal of the tumor, both cytotoxic chemotherapy and irradiation can offer additional curative benefits, but they also include a significant risk of long-term damage. Early molecular profiling aims to predict the outcome of such aggressive therapies. This prevents unnecessary damage to patients who may not need it and helps to identify those patients with remaining tumor cells who may benefit from more aggressive treatment with the intent to cure. Monitoring tumor evolution in real time allows personalized precision medicine with an immediate clinical response resulting in a better outcome. Liquid biopsy includes various methodologies already applied in numerous studies and clinical trials for common cancers including brain tumors, but information on medulloblastomas is limited. This review summarizes the recent developments of how liquid biopsy can support or even replace the standard monitoring of medulloblastomas by medical imaging or cytology and discusses what will be needed to make liquid biopsy a new gold standard in diagnosis, therapy, and follow-up of medulloblastomas for the benefit of the patients.