Role of Cell-Free DNA and Deoxyribonucleases in Tumor Progression

A biomimic anti-neuroinflammatory nanoplatform for active neutrophil extracellular traps targeting and spinal cord injury therapy

Traumatic spinal cord injury (SCI) always leads to severe neurological deficits and permanent damage. Neuroinflammation is a vital process of SCI and have become a promising target for SCI treatment. However, the neuroinflammation-targeted therapy would hinder the functional recovery of spinal cord and lead to the treatment failure. Herein, a biomimic anti-neuroinflammatory nanoplatform (DHCNPs) was developed for active neutrophil extracellular traps (NETs) targeting and SCI treatment. The curcumin-loaded liposome with the anti-inflammatory property acted as the core of the DHCNPs. Platelet membrane and neutrophil membrane were fused to form the biomimic hybrid membrane of the DHCNPs for hijacking neutrophils and neutralizing the elevated neutrophil-related proinflammatory cytokines, respectively. DNAse I modification on the hybrid membrane could achieve NETs degradation, blood spinal cord barrier, and neuron repair. Further studies proved that the DHCNPs could reprogram the multifaceted neuroinflammation and reverse the SCI process via nuclear factor kappa-B (NF-κB) pathway. We believe that the current study provides a new perspective for neuroinflammation inhibition and may shed new light on the treatment of SCI.

A Preliminary Evaluation of Advanced Oxidation Protein Products (AOPPs) as a Potential Approach to Evaluating Prognosis in Early-Stage Breast Cancer Patients and Its Implication in Tumour Angiogenesis: A 7-Year Single-Centre Study

Breast cancer (BrC) is a highly prevalent tumour among women. The high incidence and mortality rate of BrC prompts researchers to search for new markers that will provide information on the possible impact of the therapy on the risk of cancer-related events. This study aimed to investigate whether the level of advanced oxidation protein products (AOPPs) may have a potential impact on disease-free (DFS) and overall survival (OS) in BrC patients with early-stage cancer. Additionally, we tried to assess the relationship between AOPPs and angiogenic parameters. In this study, the pre- and post-treatment AOPP levels were examined in the serum of 70 newly diagnosed BrC women. The receiver operating characteristic curve identified pre- and post-treatment AOPPs to be above 9.37 μM and 10.39 μM, respectively, as the best cut-off values to predict the risk of cancer relapse. Additionally, Kaplan-Meier survival analysis indicated that pre- and post-treatment AOPPs above 9.37 μM and 10.39 μM were associated with significantly poorer OS. The uni- and multivariate Cox regression analysis highlighted that lower levels of pre- and post-treatment AOPPs were associated with a longer duration without relapse or cancer-related death. A positive correlation between concentrations of pre-treatment AOPPs and vascular endothelial growth factor A, and negative correlations with levels of soluble forms of vascular endothelial growth factor receptor type 1 and 2, were found. In conclusion, AOPPs appear to have an important role in predicting cancer-related events and may potentially serve as a simple prognostic marker in clinical practice.

Comprehensive Analysis Reveals Deoxyribonuclease 1 as a Potential Prognostic and Diagnostic Biomarker in Human Cancers

BACKGROUND

Deoxyribonuclease 1 (DNASE1) is an important gene associated with several cancers, including liver, bladder, and gastric cancer. It has been linked to autoimmune illnesses, including systemic lupus erythematosus, which may lead to cancer formation. However, the role of DNASE1 in cancer has not been studied.

MATERIALS AND METHODS

We performed a pan-cancer analysis using bioinformatics tools, including Tumor Immune Estimation Resource (TIMER), Gene Expression Profiling Interactive Analysis (GEPIA), and University of Alabama at Birmingham Cancer Data Analysis Portal (UALCAN) databases, Kaplan-Meier plotter, and cBioPortal, to investigate the expression of DNASE1 across various cancers as well as its association with immune infiltration and genetic alterations. Public datasets were used to validate DNASE1 expression in kidney renal clear cell carcinoma (KIRC) and kidney papillary renal cell carcinoma (KIRP) samples.

RESULTS

DNASE1 was found to be highly expressed in many cancers, such as bladder urothelial carcinoma (BLCA), breast invasive carcinoma (BRCA), head and neck squamous cell carcinoma (HNSC), and was lowly expressed in other cancers, including KIRC, KIRP, and thyroid carcinoma (THCA). Additionally, TIMER results showed an association of DNASE1 with immune cell infiltration in KIRC and KIRP. Survival analysis indicated that high DNASE1 expression was associated with poor prognosis in KIRC. We also discovered that altered DNASE1 expression was related to poor prognosis in The Cancer Genome Atlas (TCGA) tumors.

CONCLUSION

DNASE1 could potentially be used as a prognostic and diagnostic biomarker for KIRC and as a diagnostic biomarker for KIRP.

A Comparative Study of Different Protocols for Isolation of Murine Neutrophils from Bone Marrow and Spleen

Neutrophils are considered as the main player in innate immunity. In the last few years, it has been shown that they are involved in different physiological conditions and diseases. However, progress in the field of neutrophil biology is relatively slow due to existing difficulties in neutrophil isolation and maintenance in culture. Here we compare four protocols based on density-gradient and immunomagnetic methods for isolation of murine neutrophils from bone marrow and spleen. Neutrophil isolation was performed using Ficoll 1.077/1.119 g/mL density gradient, Ficoll 1.083/1.090/1.110 g/mL density gradient and immunomagnetic method of negative and positive selection. The different protocols were compared with respect to sample purity, cell viability, yield, and cost. The functionality of isolated neutrophils was checked by NETosis analysis and neutrophil oxidative burst test. Obtained data revealed that given purity/yield/viability/cost ratio the protocol based on cell centrifugation on Ficoll 1.077/1.119 g/mL density gradient is recommended for isolation of neutrophils from bone marrow, whereas immunomagnetic method of positive selection using Dynabeads is recommended for isolation of splenic neutrophils.

Uniform Gold Nanostructure Formation via Weakly Adsorbed Gold Films and Thermal Annealing for Reliable Localized Surface Plasmon Resonance-Based Detection of DNase-I

Deoxyribonuclease-I (DNase-I), a representative endonuclease, is an important biomarker for the diagnosis of infectious diseases and cancer progression. However, enzymatic activity decreases rapidly ex vivo, which highlights the need for precise on-site detection of DNase-I. Here, a localized surface plasmon resonance (LSPR) biosensor that enables the simple and rapid detection of DNase-I is reported. Moreover, a novel technique named electrochemical deposition and mild thermal annealing (EDMIT) is applied to overcome signal variations. By taking advantage of the low adhesion of gold clusters on indium tin oxide substrates, both the uniformity and sphericity of gold nanoparticles are increased under mild thermal annealing conditions via coalescence and Ostwald ripening. This ultimately results in an approximately 15-fold decrease in LSPR signal variations. The linear range of the fabricated sensor is 20-1000 ng mL-1 with a limit of detection (LOD) of 127.25 pg mL-1 , as demonstrated by spectral absorbance analyses. The fabricated LSPR sensor stably measured DNase-I concentrations from samples collected from both an inflammatory bowel disease (IBD) mouse model, as well as human patients with severe COVID-19 symptoms. Therefore, the proposed LSPR sensor fabricated via the EDMIT method can be used for early diagnosis of other infectious diseases.

The Effect of Cell-Free DNA from Blood Serum of Mice with Metastatic Melanoma on Enhancement of Oncogenic Properties of Melanoma Cells

Currently, a significant increase in the levels of circulating cell-free DNA (cfDNA) in the blood of patients is considered as a generally recognized marker of the development of oncological diseases. Although the tumor-associated cfDNA has been well studied, its biological functions remain unclear. In this work, we investigated the effect of cfDNA isolated from the blood serum of the mice with B16-F10 metastatic melanoma on the properties of the B16-F10 melanoma cells in vitro. It was found that the profile of cfDNA isolated from the blood serum of mice with melanoma differs significantly from the cfDNA isolated from the blood serum of healthy mice, and is similar to the genomic DNA of B16 cells with regards to abundance of oncogenes and mobile genetic elements (MGE). It was shown that the cfDNA of mice with melanoma penetrated into B16 cells, resulting in the increase in abundance of oncogenes and MGE fragments, and caused 5-fold increase of the mRNA level of the secreted DNase Dnase1l3 and a slight increase of the mRNA level of the Jun, Fos, Ras, and Myc oncogenes. cfDNA of the healthy mice caused increase of the mRNA level of intracellular regulatory DNase EndoG and 4-fold increase of the mRNA level of Fos and Ras oncogenes, which are well-known triggers of a large number of signal cascades, from apoptosis inhibition to increased tumor cell proliferation. Thus, it is obvious that the circulating cfDNA of tumor origin is able to penetrate into the cells and, despite the fact that no changes were found in the level of viability and migration activity of the tumor cells, cfDNA, even with a single exposure, can cause changes at the cellular level that increase oncogenicity of the recipient cells.

Diverse Neutrophil Functions in Cancer and Promising Neutrophil-Based Cancer Therapies

Neutrophils represent the most abundant cell type of leukocytes in the human blood and have been considered a vital player in the innate immune system and the first line of defense against invading pathogens. Recently, several studies showed that neutrophils play an active role in the immune response during cancer development. They exhibited both pro-oncogenic and anti-tumor activities under the influence of various mediators in the tumor microenvironment. Neutrophils can be divided into several subpopulations, thus contradicting the traditional concept of neutrophils as a homogeneous population with a specific function in the innate immunity and opening new horizons for cancer therapy. Despite the promising achievements in this field, a full understanding of tumor-neutrophil interplay is currently lacking. In this review, we try to summarize the current view on neutrophil heterogeneity in cancer, discuss the different communication pathways between tumors and neutrophils, and focus on the implementation of these new findings to develop promising neutrophil-based cancer therapies.

Cell-Free DNA in the Pathogenesis and Therapy of Non-Infectious Inflammations and Tumors

The basic function of the immune system is the protection of the host against infections, along with the preservation of the individual antigenic identity. The process of self-tolerance covers the discrimination between self and foreign antigens, including proteins, nucleic acids, and larger molecules. Consequently, a broken immunological self-tolerance results in the development of autoimmune or autoinflammatory disorders. Immunocompetent cells express pattern-recognition receptors on their cell membrane and cytoplasm. The majority of endogenous DNA is located intracellularly within nuclei and mitochondria. However, extracellular, cell-free DNA (cfDNA) can also be detected in a variety of diseases, such as autoimmune disorders and malignancies, which has sparked interest in using cfDNA as a possible biomarker. In recent years, the widespread use of liquid biopsies and the increasing demand for screening, as well as monitoring disease activity and therapy response, have enabled the revival of cfDNA research. The majority of studies have mainly focused on the function of cfDNA as a biomarker. However, research regarding the immunological consequences of cfDNA, such as its potential immunomodulatory or therapeutic benefits, is still in its infancy. This article discusses the involvement of various DNA-sensing receptors (e.g., absent in melanoma-2; Toll-like receptor 9; cyclic GMP-AMP synthase/activator of interferon genes) in identifying host cfDNA as a potent danger-associated molecular pattern. Furthermore, we aim to summarize the results of the experimental studies that we recently performed and highlight the immunomodulatory capacity of cfDNA, and thus, the potential for possible therapeutic consideration.

Extracellular Nucleic Acids in the Diagnosis and Progression of Colorectal Cancer

Colorectal cancer (CRC) is the 3rd most common malignant neoplasm worldwide, with more than two million new cases diagnosed yearly. Despite increasing efforts in screening, many cases are still diagnosed at a late stage, when mortality is high. This paper briefly reviews known genetic causes of CRC (distinguishing between sporadic and familial forms) and discusses potential and confirmed nucleic acid biomarkers obtainable from liquid biopsies, classified by their molecular features, focusing on clinical relevance. We comment on advantageous aspects such as better patient compliance due to blood sampling being minimally invasive, the possibility to monitor mutation characteristics of sporadic and hereditary CRC in a disease showing genetic heterogeneity, and using up- or down-regulated circulating RNA markers to reveal metastasis or disease recurrence. Current difficulties and thoughts on some possible future directions are also discussed. We explore current evidence in the field pointing towards the introduction of personalized CRC management.

Serum cell-free DNA as a new biomarker in cutaneous T-cell lymphoma

In recent years, circulating cell-free DNA (cfDNA) has received a great attention as a biomarker for various cancers. Many reports have shown that serum cfDNA levels are elevated in cancer patients and their levels correlate with prognosis and disease activity. The aim of this study was to measure serum cfDNA levels in patients with cutaneous T-cell lymphoma (CTCL) and to evaluate their correlations with hematological and clinical findings. Serum cfDNA levels in CTCL patients were significantly higher than those in healthy controls, and their levels gradually increased with the progression of the disease stage. Positive correlations were detected between serum cfDNA levels and those of lactate dehydrogenase, thymus and activation-regulated chemokine and soluble IL-2 receptor as well as neutrophil and eosinophil count in peripheral blood and neutrophil-to-lymphocyte ratio. Furthermore, CTCL patients with higher serum cfDNA levels exhibited a significantly worse prognosis. Taken together, these results suggest the potential of cfDNA as a new biomarker reflecting prognosis and disease activity in CTCL. CfDNA levels may serve as an indicator for considering the intensity and timing of subsequent therapeutic intervention.

Extracellular DNA Traps: Origin, Function and Implications for Anti-Cancer Therapies

Extracellular DNA may serve as marker in liquid biopsies to determine individual diagnosis and prognosis in cancer patients. Cell death or active release from various cell types, including immune cells can result in the release of DNA into the extracellular milieu. Neutrophils are important components of the innate immune system, controlling pathogens through phagocytosis and/or the release of neutrophil extracellular traps (NETs). NETs also promote tumor progression and metastasis, by modulating angiogenesis, anti-tumor immunity, blood clotting and inflammation and providing a supportive niche for metastasizing cancer cells. Besides neutrophils, other immune cells such as eosinophils, dendritic cells, monocytes/macrophages, mast cells, basophils and lymphocytes can also form extracellular traps (ETs) during cancer progression, indicating possible multiple origins of extracellular DNA in cancer. In this review, we summarize the pathomechanisms of ET formation generated by different cell types, and analyze these processes in the context of cancer. We also critically discuss potential ET-inhibiting agents, which may open new therapeutic strategies for cancer prevention and treatment.