Structural insights of homotypic interaction domains in the ligand-receptor signal transduction of tumor necrosis factor (TNF)

Proteomics comparison between mass-like and non-mass-like breast lesions

Background

The proteomic differences between mass-like (ML) breast lesions and non-mass-like (NML) breast lesions were compared to explore the formation mechanism of NML ultrasonic morphological characteristics.

Methods

From January to August 2021, tissue samples were collected from 10 patients with malignant ML (MML), 10 patients with malignant NML (MNML), 10 patients with benign ML (BML), and seven patients with benign NML (BNML). The proteomic differences between the BML and BNML groups and the MML and MNML groups were compared by data-independent acquisition (DIA) quantitative mass spectrometry. The differentially expressed proteins were analyzed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) networks analyses.

Results

We identified a total of 623 significantly differentially expressed proteins in the MML/MNML group, and 167 significantly differentially expressed proteins in the BML/BNML group, with relative ratios >1.2 or <-0.83. The up-regulated differential proteins were more abundant in the tumor necrosis factor (TNF) signaling pathway in both the MML/MNML and BML/BNML groups, suggesting that the TNF signaling pathway may be related to the ultrasonic morphological characteristics of breast lesions. Dual specificity mitogen-activated protein kinase 3 (MP2K3), a protein factor in the TNF signaling pathway, exhibited significant upregulation in both the malignant and BML groups.

Conclusions

The TNF signaling pathway may be associated with the ultrasonic morphological characteristics of breast lesions. MP2K3 is the up-regulated differential expression protein in the MML/MNML and BML/BNML groups, which may be related to the ultrasonic morphological characteristics of breast lesions.

Role of the Interaction of Tumor Necrosis Factor-α and Tumor Necrosis Factor Receptors 1 and 2 in Bone-Related Cells

Tumor necrosis factor-α (TNF-α) is a pleiotropic cytokine expressed by macrophages, monocytes, and T cells, and its expression is triggered by the immune system in response to pathogens and their products, such as endotoxins. TNF-α plays an important role in host defense by inducing inflammatory reactions such as phagocytes and cytocidal systems activation. TNF-α also plays an important role in bone metabolism and is associated with inflammatory bone diseases. TNF-α binds to two cell surface receptors, the 55kDa TNF receptor-1 (TNFR1) and the 75kDa TNF receptor-2 (TNFR2). Bone is in a constant state of turnover; it is continuously degraded and built via the process of bone remodeling, which results from the regulated balance between bone-resorbing osteoclasts, bone-forming osteoblasts, and the mechanosensory cell type osteocytes. Precise interactions between these cells maintain skeletal homeostasis. Studies have shown that TNF-α affects bone-related cells via TNFRs. Signaling through either receptor results in different outcomes in different cell types as well as in the same cell type. This review summarizes and discusses current research on the TNF-α and TNFR interaction and its role in bone-related cells.

A comprehensive interaction study provides a potential domain interaction network of human death domain superfamily proteins

Human death domain superfamily proteins (DDSPs) play important roles in many signaling pathways involved in cell death and inflammation. Disruption or constitutive activation of these DDSP interactions due to inherited gene mutations is closely related to immunodeficiency and/or autoinflammatory diseases; however, responsible gene mutations have not been found in phenotypical diagnosis of these diseases. In this study, we comprehensively investigated the interactions of death-fold domains to explore the signaling network mediated by human DDSPs. We obtained 116 domains of DDSPs and conducted a domain-domain interaction assay of 13,924 reactions in duplicate using amplified luminescent proximity homogeneous assay. The data were mostly consistent with previously reported interactions. We also found new possible interactions, including an interaction between the caspase recruitment domain (CARD) of CARD10 and the tandem CARD-CARD domain of NOD2, which was confirmed by reciprocal co-immunoprecipitation. This study enables prediction of the interaction network of human DDSPs, sheds light on pathogenic mechanisms, and will facilitate identification of drug targets for treatment of immunodeficiency and autoinflammatory diseases.

Intrinsic Immune Mechanisms Restricting Human Cytomegalovirus Replication

Cellular restriction factors (RFs) act as important constitutive innate immune barriers against viruses. In 2006, the promyelocytic leukemia protein was described as the first RF against human cytomegalovirus (HCMV) infection which is antagonized by the viral immediate early protein IE1. Since then, at least 15 additional RFs against HCMV have been identified, including the chromatin regulatory protein SPOC1, the cytidine deaminase APOBEC3A and the dNTP triphosphohydrolase SAMHD1. These RFs affect distinct steps of the viral replication cycle such as viral entry, gene expression, the synthesis of progeny DNA or egress. This review summarizes our current knowledge on intrinsic immune mechanisms restricting HCMV replication as well as on the viral strategies to counteract the inhibitory effects of RFs. Detailed knowledge on the interplay between host RFs and antagonizing viral factors will be fundamental to develop new approaches to combat HCMV infection.

The concentration of tumor necrosis factor in the blood serum and in the urine and selected early organ damages in patients with primary systemic arterial hypertension

Arterial hypertension is considered to be an inflammatory condition with low intensity. Therefore, an elevated concentration of inflammatory cytokines can be expected in patients with systemic arterial hypertension, including tumor necrosis factor (TNF).The study included a group of 96 persons aged 18 to 65 years: 76 patients with primary arterial hypertension and 20 healthy individuals (control group). Blood pressure was measured in all individuals using the office and ambulatory blood pressure monitoring (ABPM) measurement, blood was collected for laboratory tests [tumor necrosis factor (TNF), tumor necrosis factor receptor 1 (TNFR1)], and 24-hour urine collection was performed in which albuminuria and TNF concentration were assessed. Moreover, assessment of the intima-media thickness (IMT) in ultrasonography and left ventricular mass index (LVMI) in echocardiography were carried out.Statistically elevated TNF concentration in the blood serum (P = .0001) and in the 24-hour urine collection (P = .0087) was determined in patients with hypertension in comparison with the control group. The TNF and TNFR1 concentration in the serum and TNF in the 24-hour urine in the group of patients with arterial hypertension and organ damages and without such complications did not differ statistically significantly.We observed a positive and statistically significant correlation between TNFR1 concentration in the serum and TNF urine excretion in patients with hypertension (r = 0.369, P < .05)Patients with arterial hypertension are characterized by higher TNF concentrations in blood serum and higher TNF excretion in 24-hour urine than healthy persons.TNF and TNFR1 concentration in blood serum and TNF excretion in 24-hour urine in patients with early organ damages due to arterial hypertension do not differ significantly from those parameters in patients with arterial hypertension without organ complications.There is a positive correlation between TNFR1 concentration in the serum and TNF urine excretion in patients with hypertension.

Traumatic Brain Injury Altered Normal Brain Signaling Pathways: Implications for Novel Therapeutics Approaches

Traumatic brain injury (TBI) is the main reason of lifelong disability and casualty worldwide. In the United State alone, 1.7 million traumatic events occur yearly, out of which 50,000 results in deaths. Injury to the brain could alter various biological signaling pathways such as excitotoxicity, ionic imbalance, oxidative stress, inflammation, and apoptosis which can result in various neurological disorders such as Psychosis, Depression, Alzheimer disease, Parkinson disease, etc. In literature, various reports have indicated the alteration of these pathways after traumatic brain injury but the exact mechanism is still unclear. Thus, in the first part of this article, we have tried to summarize TBI as a modulator of various neuronal signaling pathways. Currently, very few drugs are available in the market for the treatment of TBI and these drugs only provide the supportive care. Thus, in the second part of the article, based on TBI altered signaling pathways, we have tried to find out potential targets and promising therapeutic approaches in the treatment of TBI.

Unleashing endogenous TNF-alpha as a cancer immunotherapeutic

Tumor necrosis factor (TNF)-alpha was originally identified in the 1970s as the serum mediator of innate immunity capable of inducing hemorrhagic necrosis in tumors. Today, a wide spectrum of biological activities have been attributed to this molecule, and clinical translation has mainly occurred not in using it to treat cancer, but rather to inhibit its effects to treat autoimmunity. Clinical trials utilizing systemic TNF-alpha administration have resulted in an unacceptable level of toxicities, which blocked its development. In contrast, localized administration of TNF-alpha in the form of isolated limb perfusion have yielded excellent results in soft tissue sarcomas. Here we describe a novel approach to leveraging the potent antineoplastic activities of TNF-alpha by enhancing activity of locally produced TNF-alpha through extracorporeal removal of soluble TNF-alpha receptors. Specifically, it is known that cancerous tissues are infiltrated with monocytes, T cells, and other cells capable of producing TNF-alpha. It is also known that tumors, as well as cells in the tumor microenvironment produce soluble TNF-alpha receptors. The authors believe that by selectively removing soluble TNF-alpha receptors local enhancement of endogenous TNF-alpha activity may provide for enhanced tumor cell death without associated systemic toxicities.

TNF Receptor 2 Makes Tumor Necrosis Factor a Friend of Tumors

Tumor necrosis factor (TNF) is widely accepted as a tumor-suppressive cytokine via its ubiquitous receptor TNF receptor 1 (TNFR1). The other receptor, TNFR2, is not only expressed on some tumor cells but also on suppressive immune cells, including regulatory T cells and myeloid-derived suppressor cells. In contrast to TNFR1, TNFR2 diverts the tumor-inhibiting TNF into a tumor-advocating factor. TNFR2 directly promotes the proliferation of some kinds of tumor cells. Also activating immunosuppressive cells, it supports immune escape and tumor development. Hence, TNFR2 may represent a potential target of cancer therapy. Here, we focus on expression and role of TNFR2 in the tumor microenvironment. We summarize the recent progress in understanding how TNFR2-dependent mechanisms promote carcinogenesis and tumor growth and discuss the potential value of TNFR2 in cancer treatment.

Acute phase response after fatal traumatic brain injury

An inflammatory response occurring after fatal traumatic brain injury (TBI) initiates time-dependent cascades of acute phase response. This may offer the potential to monitor postmortem biomarker levels of several pro-inflammatory cytokines to gain information about the cause of death and the trauma survival time. Cerebrospinal fluid (CSF) and serum samples were collected from forensic autopsies of 95 adult cadavers after postmortem intervals up to 6 days. The cases were divided according to their cause of death into fatal TBI (n = 46) with different survival times and age- and gender-matching non-TBI fatalities as controls (n = 49). Quantitative marker levels of interleukin-6 (IL-6), ferritin, soluble tumor necrosis factor receptor type 1, C-reactive protein, and lactate dehydrogenase were analyzed using immunoassays. Standardized statistical tests were performed to differentiate causes of death and survival time of TBI cases. The CSF IL-6, ferritin, and LDH levels after TBI were significantly higher than those in the controls (p < 0.001). Only serum IL-6 values showed comparable differences (p < 0.05). Both CSF and serum ferritin levels were discriminative between early and delayed death after TBI (p < 0.05). There were partly distinctive correlations between marker levels in both fluids with rising values after longer survival. There were up to moderate correlation between the marker levels and the postmortem interval due to postmortem hemolysis. However, neither CSF nor serum level ranges were affected by the age or gender of the subjects. This study is the first to measure all five proteins systematically in postmortem trauma cases. Ferritin and IL-6 proved themselves to be interesting postmortem biomarkers to provide specific information on the injury pattern and the survival time of traumatic fatalities. Such forensic investigations could serve as inexpensive and fast laboratory tests.