Alpha Signaling Research Articles

StressNet: Hybrid model of LSTM and CNN for stress detection from electroencephalogram signal (EEG)

Everyday tasks can cause stress, which can lead to serious medical conditions, such as depression. EEG signal processing can assist medical professionals in managing the emotional state of patients. To detect stress states in EEG signals, we propose a new architecture, StressNet, which is a combination of a two-dimensional convolutional neural network (CNN) and a long short-term memory (LSTM) network. The EEG signals are first decomposed into alpha, beta, and theta signals, which are then used to generate azimuthal projection-based images. These images are fed into the 2D CNN for feature extraction, which are then passed to the LSTM for further processing. The LSTM’s ability to remember past states makes it particularly effective in modeling the temporal dynamics of EEG signals. Finally, the StressNet model classifies the features using fully connected layers into either stress or normal classes. We evaluate the performance of our model on the DEEP and SEED datasets and compare it to other methods. The results show that the proposed StressNet model outperforms the human stress detection accuracy, achieving an accuracy of 97.8%.

Abstract 528: Endothelial Estrogen Receptor Alpha Deletion Promotes Abdominal Aortic Aneurysm In Male Mice

Introduction: Although men have a greater incidence of abdominal aortic aneurysm (AAA) compared with women, the role of sex-hormones in mediating these differences is not well understood. Given the known effect of estrogen receptor alpha (ERα) signaling in maintaining vascular wall homeostasis, the present study examines its role in the pathogenesis of AAA. Specifically, we scrutinize whether endothelial cell (EC) ERα protects against AAA via increased lysyl oxidase (LOX) activation and regulation of vascular smooth muscle cell (VSMC) phenotype. Methods: AAA was induced in male and female ECERα knockout (ECERαKO) mice and their littermates (n=6-11) by administering β-Aminopropionitrile (BAPN) via drinking water (1 mg/ml; 0.15 g/kg/d) from 3 days prior to angiotensin II (Ang II; 1 μg/kg/day) infusion for 2 weeks. The development of AAA was assessed by ultrasound measurement of aortic luminal dilation and histology. Relevant molecular mechanisms were examined in abdominal aorta and in human aortic endothelial cells (HAECs). Results: BAPN Ang II resulted in an increased incidence of AAA in male ECERαKO mice (72%), whereas female ECERαKO mice did not develop aneurysms. No difference in AAA incidence was observed between male and female littermate control mice (12.5%). Elastin fragmentation was significantly higher only in male ECERαKO mice compared to littermates, while female ECERαKO and their littermates had comparable elastin fragmentation. Ang II receptor type 1a mRNA expression was higher in male ECERαKO, whereas female ECERαKO mice had higher Ang II receptor type 1b mRNA expression. Gene expression of smooth muscle alpha-actin and smooth muscle 22 (contractile VSMC markers) was significantly higher in female aortas compared to males irrespective of genotype, whereas, osteopontin, synthetic VSMC marker was only upregulated in male ECERαKO. HAECs treated with estradiol (10 nM, 24 h) significantly increased LOX activity. Conclusions: Our findings identify a critical role of endothelial ERα in protection against AAA in male mice likely through increased LOX activity and maintenance of VSMC phenotype. Further studies are needed to delineate the crosstalk between endothelial ERα and VSMCs, and their impact in the pathogenesis of AAA.

Class A capsid assembly modulator RG7907 clears HBV-infected hepatocytes through core-dependent hepatocyte death and proliferation.

Effective therapies leading to a functional cure for chronic hepatitis B are still lacking. Class A capsid assembly modulators (CAM-As) are an attractive modality to address this unmet medical need. CAM-As induce aggregation of the HBV core protein (HBc) and lead to sustained HBsAg reductions in a chronic hepatitis B mouse model. Here, we investigate the underlying mechanism of action for CAM-A compound RG7907. RG7907 induced extensive HBc aggregation in vitro , in hepatoma cells, and in primary hepatocytes. In the adeno-associated virus (AAV)-HBV mouse model, the RG7907 treatment led to a pronounced reduction in serum HBsAg and HBeAg, concomitant with clearance of HBsAg, HBc, and AAV-HBV episome from the liver. Transient increases in alanine transaminase, hepatocyte apoptosis, and proliferation markers were observed. These processes were confirmed by RNA sequencing, which also uncovered a role for interferon alpha and gamma signaling, including the interferon-stimulated gene 15 (ISG15) pathway. Finally, the in vitro observation of CAM-A-induced HBc-dependent cell death through apoptosis established the link of HBc aggregation to in vivo loss of infected hepatocytes. Our study unravels a previously unknown mechanism of action for CAM-As such as RG7907 in which HBc aggregation induces cell death, resulting in hepatocyte proliferation and loss of covalently closed circular DNA or its equivalent, possibly assisted by an induced innate immune response. This represents a promising approach to attain a functional cure for chronic hepatitis B.

Beyond Fama-French Factors: Alpha from Short-Term Signals

Short-term alpha signals are generally dismissed in traditional asset pricing models, primarily due to market friction concerns. However, this paper demonstrates that investors can obtain a significant net alpha by applying a combination of signals to a liquid global universe and with advanced buy/sell trading rules that mitigate transaction costs. The composite model consists of short-term reversal, short-term momentum, short-term analyst revisions, short-term risk, and monthly seasonality signals. The resulting alpha is present in out-of-sample and post-publication periods and across regions, translates into long-only applications, is robust to incorporating implementation lags of several days, and is uncorrelated to traditional Fama-French factors.

An automated drug dependence detection system based on EEG

ObjectiveSubstance abuse causes damage to the brain structure and function. This research aim is to design an automated drug dependence detection system based on EEG signals in a Multidrug (MD) abuser. MethodsEEG signals were recorded from participants categorized into MD-dependents (n = 10) and Healthy Control (HC) (n = 12). The Recurrence Plot investigates the dynamic characteristics of the EEG signal. The entropy index (ENTR) measured from the Recurrence Quantification Analysis was considered the complexity index of the delta, theta, alpha, beta, gamma, and all-band EEG signals. Statistical analysis was performed by t-test. The support vector machine technique was used for the data classification. ResultsThe results show decreased ENTR indices in the delta, alpha, beta, gamma, and all-band EEG signal and increased theta band in MD abusers compared to the HC group. That indicated the reduction of complexity in the delta, alpha, beta, gamma, and all-band EEG signals in the MD group. Additionally, the SVM classifier distinguished the MD group from the HC group with 90% accuracy, 89.36% sensitivity, 90.7% specificity, and 89.8% F1 score. Conclusions and significanceThe nonlinear analysis of brain data was used to build an automatic diagnostic aid system that could identify HC people apart from those who abuse MD.

Abstract NG14: Dissecting immune microenvironment of T-cell acute lymphoblastic leukemia

Abstract NG14: Dissecting immune microenvironment of T-cell acute lymphoblastic leukemia

Trends, relationship, and model of selected service sector workers in Malaysia: Physiological responses of mental workload and mental fatigue during performing real-time tasks

Service sector is a job that is considered exposed to high mental demand. There is lack of technique to measure issues related to the mental workload and mental fatigue levels among workers. Moreover, no studies have yet developed a model to predict mental fatigue especially for service sector workers. It is necessary to investigate mental workload and mental fatigue in real time working activities. The main purpose of this study was to identify the trends and relationship between mental workload and mental fatigue level among service sector workers. Ten participants with a mean age of 35.00±8.62 (SD) years took part in the study. Two experiments in Without Rest (WoR) and With Rest (WR) segments involving data entry and arithmetic tasks were conducted. Physiological measures using Electroencephalogram (EEG), Electrooculogram (EOG) and heart rate (HR) were assessed while participants were performing the tasks. The result shows that EEG alpha signal was significantly higher at the end of WR compared to WoR segment (p<0.05). Comparison between WoR and WR segments for each task show that HR of WR tasks were significantly lower in all tasks (p<0.05). This study developed seven mental workload and mental fatigue conceptual models with strong variables correlations (r>0.05) to evaluate the variability of both parts of two types of activities, namely, data entry and arithmetic tasks. The findings highlighted that validated parameters and methods for mental fatigue and mental workload measures are brain signals and heart rate monitoring, and task performance measure. Significant findings of the study could be as a reference for organizations to plan and manage resources by optimizing mental workload condition and minimizing mental fatigue occurrence

Tert-butylhydroquinone Mitigates Renal Dysfunction in Pregnant Diabetic Rats via Attenuation of Oxidative Stress and Modulation of the iNOs/ NFkB/TNF Alpha Signalling Pathway.

The aim of the study was to determine the effect of tert-butylhydroquinone (tBHQ) supplementation on some biochemical parameters in pregnant diabetic rats and the foetus. The global incidence of gestational diabetes mellitus (GDM) has been on the increase despite current interventional therapies, underscoring the need for alternative or complementary therapeutic approaches. The objective is to determine the effect of tBHQ on blood glucose, insulin resistance, body weight, relative liver and kidney weights, serum lipid profile (total cholesterol, triacylglycerol, high-density lipoprotein cholesterol and very low-density lipoprotein cholesterol), liver function (albumin, aspartate and alanine amino transaminases) and kidney function markers (urea, creatinine and uric acid) in the sera, and study maternal and foetal renal levels of oxidative stress and inflammatory markers, foetal weights and histology of the kidney of streptozotocin (STZ)-induced GDM in rats. Twenty female pregnant rats were used, and they were divided into four groups of control (normal pregnancy), disease (diabetic untreated), metformin (received 200 mg/kg metformin dissolved in distilled water) and tBHQ groups (received 25 mg/kg tBHQ in 1% corn oil), respectively, with five rats in each group. GDM was induced in the disease and treated groups by intraperitoneal injection of STZ (45 mg/kg in sodium citrate buffer, pH 4.5). STZ induction in the disease group significantly increased their blood glucose levels (P<0.05), altered their body and foetal weights, relative liver and kidney weights, serum lipid profile, liver and kidney function markers in the sera (relative to the control), inducing oxidative stress and inflammation to the maternal and foetal kidneys and altering the maternal kidney histology, which was found to be improved following supplementation with tBHQ in a manner akin to or even better than metformin. tBHQ was found beneficial in protecting the foetal kidneys against oxidative stress and the foetus against mortality arising from maternal hyperglycaemia. Finally, the study showed the potential of tBHQ in mitigating histological changes in the maternal kidney arising from STZinduced hyperglycemia in rats.

T helper 2 cells control monocyte to tissue-resident macrophage differentiation during nematode infection of the pleural cavity

The recent revolution in tissue-resident macrophage biology has resulted largely from murine studies performed in C57BL/6 mice. Here, using both C57BL/6 and BALB/c mice, we analyze immune cells in the pleural cavity. Unlike C57BL/6 mice, naive tissue-resident large-cavity macrophages (LCMs) of BALB/c mice failed to fully implement the tissue-residency program. Following infection with a pleural-dwelling nematode, these pre-existing differences were accentuated with LCM expansion occurring in C57BL/6, but not in BALB/c mice. While infection drove monocyte recruitment in both strains, only in C57BL/6 mice were monocytes able to efficiently integrate into the resident pool. Monocyte-to-macrophage conversion required both Tcells and interleukin-4 receptor alpha (IL-4Rα) signaling. The transition to tissue residency altered macrophage function, and GATA6+ tissue-resident macrophages were required for host resistance to nematode infection. Therefore, during tissue nematode infection, T helper 2 (Th2) cells control the differentiation pathway of resident macrophages, which determines infection outcome.

Exercise improves cardiac function in the aged rats with myocardial infarction.

Exercise can improve the cardiovascular health. However, the mechanism contributing to its beneficial effect on elderly patients with myocardial infarction is obscure. 20-month-old male Sprague-Dawley rats were used to establish myocardial infarction (MI) model by permanent ligation of the left anterior descending coronary artery (LAD) of the heart, followed by 4-week interval exercise training on a motor-driven rodent treadmill. The cardiac function, myocardial fibrosis, apoptosis, oxidative stress, and inflammatory responses were determined by using pressure transducer catheter, polygraph physiological data acquisition system, Masson's trichrome staining, and ELISA to evaluate the impact of post-MI exercise training on MI. Western blot were performed to detect the activation of AMPK/SIRT1/PGC-1alpha signaling in the hearts of aged rats. Exercise training significantly improved cardiac function and reduced the cardiac fibrosis. In infarcted heart, the apoptosis, oxidative stress, and inflammation were significantly reduced after 4-week exercise training. Mechanistically, AMPK/SIRT1/PGC-1alpha pathway was activated in the myocardial infarction area after exercise training, which might participate in the protection of cardiac function. Exercise training improves cardiac function in MI rats through reduction of apoptosis, oxidative stress, and inflammation, which may mediate by the activation of AMPK/SIRT1/PGC-1alpha signaling pathway.

Psoriasis Comorbidities and Shared Disease Mechanisms – An Investigation using Systems Biology approaches

Comorbidity, or co-existing diseases and disorders, often contribute to the patient's overall burden. Psoriasis is a unique example of this. Investigating comorbidities in psoriasis patients is a time-consuming, laborious, and expensive process. To avoid these demerits, it is ideal to detect the possible comorbidities by exploiting the information from datasets deposited in NCBI. Once the comorbidities are identified through bio tools, they can be verified in patients with the required experimental tests. Patients with psoriasis will be able to receive better treatment because of these findings. Hence, in this study, we have utilized the Network Analyst tool to identify the comorbidities associated with psoriasis. We are reporting the protein interaction of fifteen subnetworks, whose GO CC and Reactome pathways were investigated. Notably, subnetwork 2 was involved in xenobiotic metabolism and GABA synthesis. Subnetworks 3, 9, 10, and 13 were associated with the synthesis of sphinganine, galanin, circadian proteins, and urea, respectively. Subnetwork 4 proteins synthesized bile acids and 25-hydroxy cholesterol, whereas subnetworks 7 and 16 produced chemokines, CXCL10 and CXCL1 respectively. The later subnetworks along with subnetwork 9 were involved in G alpha (i) signaling events. Due to the up-regulation of certain proteins in these subnetworks, they cause various types of diseases. The development of comorbidities from these subnetworks is lime lighted.

BAP18 facilitates CTCF-mediated chromatin accessible to regulate enhancer activity in breast cancer.

The estrogen receptor alpha (ERα) signaling pathway is a crucial target for ERα-positive breast cancer therapeutic strategies. Co-regulators and other transcription factors cooperate for effective ERα-related enhancer activation. Recent studies demonstrate that the transcription factor CTCF is essential to participate in ERα/E2-induced enhancer transactivation. However, the mechanism of how CTCF is achieved remains unknown. Here, we provided evidence that BAP18 is required for CTCF recruitment on ERα-enriched enhancers, facilitating CTCF-mediated chromatin accessibility to promote enhancer RNAs transcription. Consistently, GRO-seq demonstrates that the enhancer activity is positively correlated with BAP18 enrichment. Furthermore, BAP18 interacts with SMARCA1/BPTF to accelerate the recruitment of CTCF to ERα-related enhancers. Interestingly, BAP18 is involved in chromatin accessibility within enhancer regions, thereby increasing enhancer transactivation and enhancer-promoter looping. BAP18 depletion increases the sensitivity of anti-estrogen and anti-enhancer treatment in MCF7 cells. Collectively, our study indicates that BAP18 coordinates with CTCF to enlarge the transactivation of ERα-related enhancers, providing a better understanding of BAP18/CTCF coupling chromatin remodeling and E-P looping in the regulation of enhancer transcription.

Differences in the tumor transcriptomic profile of patients (pts) with advanced prostate cancer (PCa) with and without diabetes mellitus (DM).

244 Background: Pre-existing DM is associated with increased PCa specific and all-cause mortality in men with prostate cancer (PMID: 27652121). However, the underlying reasons are unclear. We hypothesized that transcriptomic profile of metastatic PCa pts with diagnosis of DM prior to the diagnosis of metastatic disease and start of systemic therapy will be different from those without DM. Methods: In this IRB-approved retrospective study, advanced PCa pts with available RNA profiling of treatment naïve tumor tissue through a CLIA-certified laboratory were included. Based on pre-existing DM prior to onset of metastatic disease, pts was grouped into DM and non-DM. Differential gene expression analysis between the two groups was performed using DeSeq2. These results were subjected to Gene Set Enrichment software analysis (GSEA) to identify pathways enriched in each cohort. Gene ontology analysis using TopGO software was done to identify the biological process occurring at the molecular level of these differentially expressed genes. All bioinformatic analysis was conducted in R studio, version 4.1.1. Results: 75 pts were eligible and included: 20 DM vs 55 non-DM. Baseline characteristics (DM vs non-DM): median age 63.5 vs 64 years; median PSA at diagnosis 20 vs 18.85ng/mL; de novo disease: 55% vs 43.6%; Gleason score ≥8: 60% vs 74.5%. DM pts had upregulation of the following pathways: TNF alpha signaling, inflammatory response, IL-6 JAK STAT3 signaling, heme metabolism, and the p53 pathway vs non-DM pts. Gene ontology analysis and individual differential gene expression profiles will be reported at the meeting. Conclusions: Our study found that pre-existing DM is associated with upregulation of inflammatory pathways in pts with PCa These hypothesis-generating results need external validation. Identification of transcriptomic biomarkers in these subsets of pts may help with further drug development. [Table: see text]

Sestrin2 Signaling Pathway Regulates Podocyte Biology and Protects against Diabetic Nephropathy.

Sestrin2 regulates cell homeostasis and is an upstream signaling molecule for several signaling pathways. Sestrin2 leads to AMP-activated protein kinase- (AMPK-) and GTPase-activating protein activity toward Rags (GATOR) 1-mediated inhibition of mammalian target of rapamycin complex 1 (mTORC1), thereby enhancing autophagy. Sestrin2 also improves mitochondrial biogenesis via AMPK/Sirt1/peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α) signaling pathway. Blockade of ribosomal protein synthesis and augmentation of autophagy by Sestrin2 can prevent misfolded protein accumulation and attenuate endoplasmic reticulum (ER) stress. In addition, Sestrin2 enhances P62-mediated autophagic degradation of Keap1 to release nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2 release by Sestrin2 vigorously potentiates antioxidant defense in diabetic nephropathy. Impaired autophagy and mitochondrial biogenesis, severe oxidative stress, and ER stress are all deeply involved in the development and progression of diabetic nephropathy. It has been shown that Sestrin2 expression is lower in the kidney of animals and patients with diabetic nephropathy. Sestrin2 knockdown aggravated diabetic nephropathy in animal models. In contrast, upregulation of Sestrin2 enhanced autophagy, mitophagy, and mitochondrial biogenesis and suppressed oxidative stress, ER stress, and apoptosis in diabetic nephropathy. Consistently, overexpression of Sestrin2 ameliorated podocyte injury, mesangial proliferation, proteinuria, and renal fibrosis in animal models of diabetic nephropathy. By suppressing transforming growth factor beta (TGF-β)/Smad and Yes-associated protein (YAP)/transcription enhancer factor 1 (TEF1) signaling pathways in experimental models, Sestrin2 hindered epithelial-mesenchymal transition and extracellular matrix accumulation in diabetic kidneys. Moreover, modulation of the downstream molecules of Sestrin2, for instance, augmentation of AMPK or Nrf2 signaling and inhibition of mTORC1, has been protective in diabetic nephropathy. Regarding the beneficial effects of Sestrin2 on diabetic nephropathy and its interaction with several signaling molecules, it is worth targeting Sestrin2 in diabetic nephropathy.

Gene Set Enrichment Analysis and Genetic Experiment Reveal Changes in Cell Signaling Pathways Induced by α-Synuclein Overexpression

Abnormal accumulation of alpha synuclein (α-Syn) in sporadic and familial Parkinson's disease (PD) may be a key step in its pathogenesis. In this study, the expression matrix of the GSE95427 dataset after α-Syn overexpression in human glioma cell line H4 was obtained from the GEO database. We used the Gene Set Enrichment Analysis (GSEA) method to reanalyze this dataset to evaluate the possible functions of α-Syn. The results showed that the tumor necrosis factor alpha (TNF-α) signal was significantly activated in α-Syn-overexpressing cells, and oxidative phosphorylation signal, extracellular matrix signal, cell cycle related signal and fatty acid metabolism signal were significantly inhibited. Moreover, we employed the α-Syn-expressing transgenic Drosophila model of Parkinson's disease and knocked-down eiger, a TNF superfamily ligand homologue, indicating that the TNF-α pathway plays a role in the common pathogenesis of synucleinopathies. Our analysis based on GSEA data provides more clues for a better understanding of α-Syn function.

Estrogen receptor alpha signaling in dendritic cells modulates autoimmune disease phenotype in mice.

Estrogen is a disease-modifying factor in multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE) via estrogen receptor alpha (ERα). However, the mechanisms by which ERα signaling contributes to changes in disease pathogenesis have not been completely elucidated. Here, we demonstrate that ERα deletion in dendritic cells (DCs) of mice induces severe neurodegeneration in the central nervous system in a mouse EAE model and resistance to interferon beta (IFNβ), a first-line MS treatment. Estrogen synthesized by extragonadal sources is crucial for controlling disease phenotypes. Mechanistically, activated ERα directly interacts with TRAF3, a TLR4 downstream signaling molecule, to degrade TRAF3 via ubiquitination, resulting in reduced IRF3 nuclear translocation and transcription of membrane lymphotoxin (mLT) and IFNβ components. Diminished ERα signaling in DCs generates neurotoxic effector CD4+ T cells via mLT-lymphotoxin beta receptor (LTβR) signaling. Lymphotoxin beta receptor antagonist abolished EAE disease symptoms in the DC-specific ERα-deficient mice. These findings indicate that estrogen derived from extragonadal sources, such as lymph nodes, controls TRAF3-mediated cytokine production in DCs to modulate the EAE disease phenotype.

Chapter 21 - Isolated and combined dystonias: Update

Dystonia is a hyperkinetic movement disorder with a unique motor phenomenology that can manifest as an isolated clinical syndrome or combined with other neurological features. This chapter reviews the characteristic features of dystonia phenomenology and the syndromic approach to evaluating the disorders that may allow us to differentiate the isolated and combined syndromes. We also present the most common types of isolated and combined dystonia syndromes. Since accelerated gene discoveries have increased our understanding of the molecular mechanisms of dystonia pathogenesis, we also present isolated and combined dystonia syndromes by shared biological pathways. Examples of these converging mechanisms of the isolated and combined dystonia syndromes include (1) disruption of the integrated response pathway through eukaryotic initiation factor 2 alpha signaling, (2) disease of dopaminergic signaling, (3) alterations in the cerebello-thalamic pathway, and (4) disease of protein mislocalization and stability. The discoveries that isolated and combined dystonia syndromes converge in shared biological pathways will aid in the development of clinical trials and therapeutic strategies targeting these convergent molecular pathways.

Upregulation of OTX2-AS1 is Associated With Immune Infiltration and Predicts Prognosis of Gastric Cancer.

It is unclear whether the long non-coding RNA (lncRNA) OTX2 antisense RNA 1 (OTX2-AS1) plays a pivotal role in gastric cancer (GC). An analysis of The Cancer Genome Atlas (TCGA) database data and bioinformatics was used to explore the relationship between OTX2-AS1 and GC in the current study. We evaluated the relationship between clinical features and OTX2-AS1 expression, prognostic factors, and the significant involvement of OTX2-AS1 in function using various statistical methods, such as Kaplan-Meier method, Cox regression analysis, Gene Set Enrichment Analysis (GSEA), and immune infiltration analysis. GC cell lines were tested for OTX2-AS1 expression using qRT-PCR. A high level of OTX2-AS1 expression was significantly and negatively associated with Helicobacter pylori (H pylori) infection in GC patients (P = .006) and predicted a poorer overall survival (OS) (HR: 1.54; 95% CI: 1.10-2.14; P = .011), progression-free interval (PFI) (HR: 1.75; 95% CI: 1.22-2.51; P = .002) and disease-specific survival (DSS) (HR: 1.85; 95% CI: 1.21-2.85; P = .005) in GC patients. There was an independent correlation between OTX2-AS1 expression (HR: 1.771; 95% CI: 1.164-2.696; P = .008) and OS in patients with GC. There were differential enrichments for the OTX2-AS1 high expression phenotype in the olfactory transduction, G alpha (s) signaling events, keratinization, olfactory signaling pathway, and preimplantation embryo. OTX2-AS1 expression may be related to certain immune-infiltrating cells. Compared to gastric epithelial cells (GES-1), GC cell lines showed a significant increase in OTX2-AS1 expression. There was a significant association between OTX2-AS1 expression in GC patients and poor survival, suggesting that it may be a useful biomarker for prognosis and immunotherapy outcome of stomach adenocarcinoma (STAD) in GC.

Type I interferon signaling promotes radioresistance in head and neck cancer.

Despite the promise of concurrent radiotherapy (RT) and immunotherapy in head and neck cancer (HNC), multiple randomized trials of this combination have had disappointing results. To evaluate potential immunologic mechanisms of RT resistance, we compared pre-treatment HNCs that developed RT resistance to a matched cohort that achieved curative status. Gene set enrichment analysis demonstrated that a pre-treatment pro-immunogenic tumor microenvironment (TME), including type II interferon [interferon gamma (IFNγ)] and tumor necrosis factor alpha (TNFα) signaling, predicted cure while type I interferon [interferon alpha (IFNα)] enrichment was associated with an immunosuppressive TME found in tumors that went on to recur. We then used immune deconvolution of RNA sequencing datasets to evaluate immunologic cell subset enrichment. This identified M2 macrophage signaling associated with type I IFN pathway expression in RT-recurrent disease. To further dissect mechanism, we then evaluated differential gene expression between pre-treatment and RT-resistant HNCs from sampled from the same patients at the same anatomical location in the oral cavity. Here, recurrent samples exhibited upregulation of type I IFN-stimulated genes (ISGs) including members of the IFN-induced protein with tetratricopeptide repeats (IFIT) and IFN-induced transmembrane (IFITM) gene families. While several ISGs were upregulated in each recurrent cancer, IFIT2 was significantly upregulated in all recurrent tumors when compared with the matched pre-RT specimens. Based on these observations, we hypothesized sustained type I IFN signaling through ISGs, such as IFIT2, may suppress the intra-tumoral immune response thereby promoting radiation resistance.

Assessment of Mouse Liver Histopathology Following Exposure to HFPO-DA With Emphasis on Understanding Mechanisms of Hepatocellular Death.

Ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate (HFPO-DA) is a short chain member of per- and polyfluoroalkyl substances (PFAS). To better understand the relevance of histopathological effects seen in livers of mice exposed to HFPO-DA for human health risk assessment, histopathological effects were summarized from hematoxylin and eosin (H&E)-stained sections in several repeat-dose toxicity studies in mice. Findings across studies revealed histopathological changes consistent with peroxisomal proliferation, whereas two reports of steatosis could not be confirmed in the published figures. In addition, mechanisms of hepatocellular death were assessed in H&E sections as well as with the apoptotic marker cleaved caspase-3 (CCasp3) in newly cut sections from archived liver blocks from select studies. A comparison of serially CCasp3 immunolabeled and H&E-stained sections revealed that mechanisms of hepatocellular death cannot be clearly discerned in H&E-stained liver sections alone as several examples of putatively necrotic cells were positive for CCasp3. Published whole genome transcriptomic data were also reevaluated for enrichment of various forms of hepatocellular death in response to HFPO-DA, which revealed enrichment of apoptosis and autophagy, but not ferroptosis, pyroptosis, or necroptosis. These morphological and molecular findings are consistent with transcriptomic evidence for peroxisome proliferator-activated receptor alpha (PPARα) signaling in HFPO-DA exposed mice.