Hepatocellular Carcinoma Presenting as a Clival Mass

Introduction: Hepatocellular carcinoma (HCC) comprises the majority of primary liver cancer and has a poor prognosis. Clivus metastasis is rare with only a few reported cases in the medical literature. We report a case of a patient who presented with clival mass found to have metastatic HCC. Case Description/Methods: A 63-year-old woman presented for neurosurgical evaluation after she was found to have a skull base mass on computerized tomography (CT) of the head at an outside hospital. She endorsed dysphagia for three months, however denied headaches or visual disturbances. A magnetic resonance imaging (MRI) revealed a 5.4 cm by 2.9 cm by 3.6 cm mass in the clivus, which was deemed as the cause of dysphagia (Figure 1a). The patient subsequently underwent an endoscopic transsphenoidal resection of the clival mass. Histopathology from the tissue revealed a hepatoid carcinoma, concerning for metastatic HCC (Figure 1b and 2c). Immunohistochemical strains were positive for hepatocytic marker arginase-1 (Figure 1d). Laboratory studies revealed alpha fetoprotein (AFP) of 56,344 ng/mL, CA-125 of 376 ng/mL, normal B-HCG and carcinoembryonic antigen (CEA). Thereafter, a triple phase CT of the liver revealed two LI-RADS 5 lesions suggestive of HCC as the primary malignancy. Patient's case was discussed at multidisciplinary tumor board with recommendations for systemic immunotherapy with atezolimumab plus bevacizumab and radiation therapy to the clivus. Discussion(s): The incidence of HCC has almost tripled since the 1980s making it the fastest rising cause of cancer related deaths. Metastasis to the brain comprises 0.26% to 2.2% of cases and the skull base is the most rarely affected anatomical site. Although CNS presentation is rare, we may see more neurological manifestations of metastatic HCC with the persistence of chronic hepatitis infections, the rise of metabolic diseases such as NASH, and an increase in alcohol-related liver disease during the COVID-19 pandemic. Although exceedingly rare, metastasis to the clivus should be considered in the differential diagnosis of skull base masses. Despite detection and treatment, prognosis remains poor and emphasis should be placed on consistent HCC surveillance. This case emphasizes that skull masses must be evaluated diligently as they can be the first sign of underlying liver malignancy. Given the morbidity and mortality associated with HCC, recognition of atypical manifestations of HCC can lead to a prompt diagnosis and initiation of life-saving treatment. (Figure Presented).

Prolonged stay and endothelial dysfunction in hospitalized patients with covid-19

Introduction: COVID-19 is not only a respiratory disease, produces a severe systemic and multi-organ response. This illness generates vascular disorders, leading the patient to endothelial dysfunction. It acutely and chronically affects the patient's evolution, prolonging the patient's stay and worsening life prognosis. Objective(s): To evaluate differences in endothelial dysfunction present in patients hospitalized for COVID-19 who had a hospital stay longer than 18 days compared to those who did not. Method(s): A prospective cohort study was conducted. Hospitalized patients with confirmed SARS-COV 2 andolder than 18 years were included. Subjects in whom endothelial function markers could not be processed wereexcluded. Endothelial dysfunction was evaluated using E-selectin, endothelin-1, glutathione-s-transferase, arginase, and MDAM. A prolonged hospital stay was established >=18 days. Result(s): A total of 165 patients were evaluated, the average age of the population was 57.18 +/- 13.37 years, 73.33% were men. Subjects with prolonged hospital stay were older (59.38 +/- 12.08 vs 51.15 +/- 14.96, p=0.004), a higher number of patients required intubation (87.60 % vs 75, p=0.049) and e-selectin (1 [0.79 - 1.32] vs 0.88 [0.68 -1.14], p=0.0323) compared to subjects without prolonged hospital stay. Conclusion(s): Hospitalized patients over 18 days showed elevated levels of E-selectin reflecting endothelial damage, affecting vascular homeostasis, added to this, a significant number of them were intubated, increasing the risk of mortality, as well as future cardiovascular complications.

The level of nitric oxide and arginase activity in patients with arterial hypertension and diabetes mellitus during COVID-19

The aim of this study was to assess the level of nitric oxide production and arginase activity in patients with arterial hypertension and type II diabetes mellitus during infection with SarS-CoV-2. The study groups included patients with arterial hypertension, patients with arterial hypertension combined with a severe course of COVID-19 and patients who, in addition to arterial hypertension and COVID-19, were suffering from type II diabetes mellitus. The volunteers without any clinical signs of diseases and normal blood pressure formed the control group. It has been established that arterial hypertension, combined with COVID-19 occurs along with reduced L-arginine, nitric oxide, superoxide dismutase activity and increased arginase activity. At the same time, the presence of arterial hypertension in patients with diabetes and coronavirus disease is accom-panied by a decline in the content of L-arginine and arginase activity. Our study's results may help scientists find new pharmacological targets in the future treatment of coronavirus disease and comorbid disorders. © 2022, Palladin Institute of Biochemistry of the NASU. All rights reserved.

Genetic regulation of iron homeostasis in sideropenic patients with mild COVID-19 disease under a new oral iron formulation: Lessons from a different perspective.

BACKGROUND: Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) needs iron to replicate itself. Coronaviruses are able to upregulate Chop/Gadd153 and Arg1 genes, consequently leading to CD8 lymphocytes decrease, degradation of asparagine and decreased nitric oxide (NO), thus impairing immune response and antithrombotic functions. Little is known about regulation of genes involved in iron metabolism in paucisymptomatic patients with COVID-19 disease or in patients with iron deficiency treated with sucrosomial iron. METHODS: Whole blood was taken from the COVID-19 patients and from patients with sideropenic anemia, treated or not (control group) with iron supplementations. Enrolled patients were: affected by COVID19 under sucrosomal iron support (group A), affected by COVID-19 not under oral iron support (group B), iron deficiency not under treatment, not affected by COVID19 (control group). After RNA extraction and complementary DNA (cDNA) synthesis of Arg1, Hepcidin and Chop/Gadd153, gene expression from the 3 groups was measured by qRT-PCR. M2 macrophages were detected by cytofluorimetry using CD163 and CD14 markers. RESULTS: Forty patients with COVID-19 (group A), 20 patients with iron deficiency treated with sucrosomial iron (group B) and 20 patients with iron deficiency not under treatment (control group) were enrolled. In all the patients supported with oral sucrosomial iron, the gene expression of Chop, Arg1 and Hepcidin genes was lower than in sideropenic patients not supported with iron, M1 macrophages polarization and functional iron deficiency was also lower in group A and B, than observed in the control group. CONCLUSIONS: New oral iron formulations, as sucrosomial iron, are able to influence the expression of genes like Chop and Arg1 and to influence M2 macrophage polarization mainly in the early phase of COVID-19 disease.

Immunoregulatory role of nucleated erythroid cells

Nucleated erythroid cells (NEC) are the precursors of the most massive population of human cells – erythrocytes, for which functions of hemo- and immunoregulation have been shown at various stages of ontogenesis and in various organs and tissues of the human body. NEC perform this function by secreting cytokine proteins, growth factors, enzymes such as arginase-2, ROS, and by surface molecules PD-L1 and PD-L2. Their important regulatory role has been shown for the formation of fetoplacental immunosuppression, immunosuppression during pregnancy, suppression of the response against commensals in the gastrointestinal tract, in the pathogenesis of bacterial and viral infections in adults, in the pathogenesis of tumor growth and autoimmune diseases, as well as participation in the recognition of pathogen-associated molecular patterns using Toll-like receptors in fish and birds. Such qualities, together with their number and width of distribution, represent NEC as active participants in hemo- and immunoregulation, which makes it important to study their regulatory role in health and disease.

Targeting Arginine in COVID-19-Induced Immunopathology and Vasculopathy.

Coronavirus disease 2019 (COVID-19) represents a major public health crisis that has caused the death of nearly six million people worldwide. Emerging data have identified a deficiency of circulating arginine in patients with COVID-19. Arginine is a semi-essential amino acid that serves as key regulator of immune and vascular cell function. Arginine is metabolized by nitric oxide (NO) synthase to NO which plays a pivotal role in host defense and vascular health, whereas the catabolism of arginine by arginase to ornithine contributes to immune suppression and vascular disease. Notably, arginase activity is upregulated in COVID-19 patients in a disease-dependent fashion, favoring the production of ornithine and its metabolites from arginine over the synthesis of NO. This rewiring of arginine metabolism in COVID-19 promotes immune and endothelial cell dysfunction, vascular smooth muscle cell proliferation and migration, inflammation, vasoconstriction, thrombosis, and arterial thickening, fibrosis, and stiffening, which can lead to vascular occlusion, muti-organ failure, and death. Strategies that restore the plasma concentration of arginine, inhibit arginase activity, and/or enhance the bioavailability and potency of NO represent promising therapeutic approaches that may preserve immune function and prevent the development of severe vascular disease in patients with COVID-19.

The chemical constituents of Sterculia comosa (wall) Roxb woods for arginase inhibitory, antioxidant activity, and molecular docking against SARS CoV-2 protein.

Flavonoids and phenols have an arginase inhibitory and antioxidant activity. The Sterculia genus has phenols and flavonoids content. This study aimed to investigate the arginase inhibitory and antioxidant activity of the chemical constituent of Sterculia comosa (wall) Roxb and also their binding affinities to arginase. The most active extract was methanol extract. This active extract was determined for its arginase inhibitory and antioxidant activity, determined the total phenols and total flavonoids, and identified chemical compound. The methanol extract has IC50 2.787 µg/ml for arginase inhibitory activity and IC50 4,199 µg/ml for DPPH scavenging activity. The total phenols 723.61 mg GAE/gr, total flavonoids content 28.96 mg QE/gr extract. The chemical constituent: KC4.4.6 ((-)-2-(E)-caffeoyl-D-glyceric acid) and KC4.4.5.1 (trans-isoferulic acid) have an arginase inhibitory activity KC4.4.6: 98,03 µg/ml and KC4.4.5.1: 292,58 µg/ml. Antioxidant activity with DPPH methods KC4.4.6: 48,77 µg/ml and KC4.4.5.1: 88,08 µg/ml. Antioxidant by FRAP methods KC4.4.6: 16,4 FeEAC mol/g and KC4.4.5.1: 15,79 FeEAC mol/g. The isolate trans-isoferulic acid predicted has good interaction to arginase. Isolate KC4.4.6. Predicted has good interaction to PLPro of SARS CoV-2 PLpro. However, both isolates did not show good interaction to 3CLPro, nsp12, and Spike protein of SARS CoV-2.

Erythrocytes Induce Vascular Dysfunction in COVID-19.

Current knowledge regarding mechanisms underlying cardiovascular complications in patients with COVID-19 is limited and urgently needed. We shed light on a previously unrecognized mechanism and unravel a key role of red blood cells, driving vascular dysfunction in patients with COVID-19 infection. We establish the presence of profound and persistent endothelial dysfunction in vivo in patients with COVID-19. Mechanistically, we show that targeting reactive oxygen species or arginase 1 improves vascular dysfunction mediated by red blood cells. These translational observations hold promise that restoring the redox balance in red blood cells might alleviate the clinical complications of COVID-19-associated vascular dysfunction.

Arginine-hydrolyzing enzymes for electrochemical biosensors

Since L-Arginine (Arg) is a semi-essential amino acid for humans, its adequate amount must be consumed in the diet to prevent certain negative consequences related to insufficient synthesis of this amino acid under specific physiological conditions. Arg metabolism results in the production of a biochemically diverse range of such products as urea, some amino acids, creatine, polyamines, nitric oxide, etc. Arg, an important biomarker in clinical diagnostics, is also used for prevention/treatment of different diseases, including cancer and COVID-19. Furthermore, it serves as an indicator of food and beverages quality. A variety of optic and electrochemical methods for Arg determination have already been suggested. The biosensor systems based on the enzymes of Arg metabolism were shown to be the most promising tools for Arg assay. This review focuses on the peculiarities of electrochemical biosensors for Arg assay based on the use of Arg-degrading enzymes and on the analysis of their advantages as compared to other approaches.

A Randomised Evaluation of Low-Dose Ara-C Plus BCT-100 Versus Low Dose Ara-C in Older Patients with Acute Myeloid Leukaemia: Results from the LI-1 Trial

Background: Among patients with Acute Myeloid Leukaemia (AML) over the age of 60, a considerable number are not considered suitable for intensive remission-induction chemotherapy. Survival in these patients is poor, whether they are treated using hypomethylating agents or low-dose ara-C (LDAC). The possibility of combination therapy with additional agents represents an attractive option. Arginine metabolism plays a key role in AML pathogenesis (Mussai et al. Blood 2013);BCT-100 is a pegylated recombinant human arginase that leads to a rapid depletion in extracellular and intracellular arginine concentrations resulting in G0/G1 arrest, and subsequent death by necrosis. BCT-100 demonstrates significant activity as single-agent against AML cell lines, AML xenografts and primary AML blasts from newly diagnosed or relapsed patients (Mussai et al. Blood 2015). Importantly BCT-100 is synergistic in combination with cytarabine. Aims: To assess the efficacy of LDAC+BCT100 versus LDAC alone in patients aged 60+ unsuitable for intensive therapy, in a “pick a winner” design. This design allows several treatments to be assessed simultaneously in a randomised fashion, with the aim of doubling 2-year survival from 11% to 22% (HR 0.69), with interim assessments after 50 and 100 patients per arm are recruited. Methods: LDAC was given at 20mg BD SC on days 1-10 of each course. Patients randomised to the combination received LDAC as above with BCT-100 1600U/kg on Days 1, 8, 15 and 22 as a 1-hour intravenous infusion. Courses occurred at 4-6 week intervals. Toxicities were recorded using CTCAE version 3. Pharmacokinetic and biomarker samples were assessed in BCT-100 patients. Results here are based upon median follow-up of 3.8 months (range: 0.1 - 20.6 months) Results: Between September 2018 and December 2020, 83 patients were randomised. The trial was prematurely closed due to the COVID pandemic and did not reach the pre-planned first evaluation. Median age was 76.7 years (range 62-88). Overall, 65% were male;70% de novo AML, 23% secondary AML, and 6% high risk MDS;2% favourable, 59% intermediate, 23% adverse and 15% unknown/unreported cytogenetics. Median of 2 courses was delivered in either arm (mean 2 LDAC, 2 LDAC+BCT, range for both: 1-12). BCT-100 leads to a depletion of arginine from baseline in the majority of patients. Overall response (CR/CRi) was achieved in 12/81 patients (15%), (LDAC+BCT-100 15%, LDAC 15%, R 1.03 (0.30, 3.51),P=0.963). Thirty-day mortality was not significantly increased (18% vs 11%, HR 1.71 (0.50, 5.84), P=0.393;and 1-year survival showed no evidence of a difference (31% vs 30%, HR 1.28 (0.72, 2.25). Median overall survival time was 3.8 vs 6.4months;overall survival HR 1.11 (0.64, 1.90), P=0.715. The most common cause of death was resistant/recurrent disease: 12(46%) vs 16(59%). BCT-100 was not associated with any haematological toxicity;although rare grade 3/4 cardiac and hepatic events were reported, these were not significantly increased with BCT-100. Summary: The addition of BCT-100 to LDAC did not improve response rate or survival. BCT-100 was well tolerated with an acceptable toxicity profile. Further clinical evaluation of BCT-100 induced arginase depletion continues in a variety of malignancies. Acknowledgements: We are grateful to Blood Cancer UK for funding the trial and Bio-Cancer Treatment International for providing drug and additional support for this Investigator Initiated Study. Figure 1. OS All patients [Formula presented] Disclosures: Knapper: Jazz: Consultancy, Speakers Bureau;Pfizer: Consultancy, Speakers Bureau;Astellas: Ended employment in the past 24 months, Speakers Bureau;Novartis: Consultancy, Research Funding, Speakers Bureau. McMullin: Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Other: clinical trial support, Research Funding;Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau;Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau;Abb ie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau;AOP Orphan: Research Funding, Speakers Bureau. Copland: Incyte: Honoraria, Research Funding, Speakers Bureau;Novartis: Honoraria, Speakers Bureau;Pfizer: Honoraria, Speakers Bureau;Cyclacel Ltd: Research Funding;Astellas: Honoraria, Speakers Bureau;Jazz: Honoraria, Speakers Bureau. Russell: Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding;Novartis: Speakers Bureau;Astellas: Membership on an entity's Board of Directors or advisory committees;Jazz: Research Funding, Speakers Bureau.

Erythrocytes induce vascular dysfunction in COVID-19

Background: Vascular injury has been implicated as a major cause of clinical complications in patients with coronavirus disease 2019 (COVID-19). Autopsy studies have revealed destruction of the endothelial cell lining, which might explain cardiovascular alterations arising from the infection. However, data demonstrating endothelial dysfunction during ongoing infection are sparse, and the underlying mechanisms are still largely unknown. Red blood cells (RBCs) are affected by COVID-19 with alterations in their structure and function, possibly contributing to vascular injury via increased oxidative stress. Purpose: To determine the presence of endothelial dysfunction in patients with COVID-19 and to explore the RBC as a possible mediator of such dysfunction. Methods: The study was performed on 17 patients hospitalized for moderate COVID-19 infection and age-and sex-matched healthy subjects. Inclusion criteria of the COVID-19 patients were PCR-verified SARS-CoV2 infection, pulmonary infiltrates on x-ray, oxygen demand during hospital stay and ≤ one cardiovascular co-morbidity. Microvascular endothelial function in vivo was assessed with a pulse amplitude tonometry device on each index finger at baseline and during reactive hyperemia and expressed as reactive hyperemia index (RHI). RBCs from COVID-19 patients (C19-RBCs) and healthy subjects (H-RBCs) were incubated with isolated rat aortic segments for evaluation of endothelium-dependent and -independent relaxation. Results: COVID-19 patients displayed profound impairment in endothelial function in vivo with RHI 1.56 (1.30-1.81, median and interquartile range) compared to healthy subjects 2.36 (1.97-2.79, p<0.001). C19-RBCs induced severe impairment in both endothelium-dependent (27% maximal relaxation) and -independent relaxations (54%) compared to H-RBCs (67% and 95% relaxation, respectively). Further, C19-RBCs induced upregulation of vascular arginase 1 (∼2 fold increase compared to H-RBCs) and markers of oxidative stress (∼6 fold). Consequently, inhibition of vascular arginase or superoxide attenuated the impairment in endothelial function induced by C19-RBCs. C19-RBCs were characterized by increased production of reactive oxygen species (∼1.4 fold) and reduced export of the nitric oxide metabolite nitrate. Following pre-incubation with interferon-γ, but not interleukin-6 or tumor necrosis factor-α, H-RBCs induced impairment in endothelial function. Conclusions: This study demonstrates the presence of marked endothelial dysfunction in an otherwise mainly healthy patient group hospitalized for COVID-19, and clearly implicates a central role of the RBC as a mediator of endothelial injury through enhancement of reactive oxygen species and arginase. These data shed light on a new pathological mechanism underlying vascular dysfunction in COVID-19 patients and may lay the foundation for future therapeutic developments.

Severe COVID-19 Is Characterized by an Impaired Type I Interferon Response and Elevated Levels of Arginase Producing Granulocytic Myeloid Derived Suppressor Cells.

COVID-19 ranges from asymptomatic in 35% of cases to severe in 20% of patients. Differences in the type and degree of inflammation appear to determine the severity of the disease. Recent reports show an increase in circulating monocytic-myeloid-derived suppressor cells (M-MDSC) in severe COVID 19 that deplete arginine but are not associated with respiratory complications. Our data shows that differences in the type, function and transcriptome of granulocytic-MDSC (G-MDSC) may in part explain the severity COVID-19, in particular the association with pulmonary complications. Large infiltrates by Arginase 1+ G-MDSC (Arg+G-MDSC), expressing NOX-1 and NOX-2 (important for production of reactive oxygen species) were found in the lungs of patients who died from COVID-19 complications. Increased circulating Arg+G-MDSC depleted arginine, which impaired T cell receptor and endothelial cell function. Transcriptomic signatures of G-MDSC from patients with different stages of COVID-19, revealed that asymptomatic patients had increased expression of pathways and genes associated with type I interferon (IFN), while patients with severe COVID-19 had increased expression of genes associated with arginase production, and granulocyte degranulation and function. These results suggest that asymptomatic patients develop a protective type I IFN response, while patients with severe COVID-19 have an increased inflammatory response that depletes arginine, impairs T cell and endothelial cell function, and causes extensive pulmonary damage. Therefore, inhibition of arginase-1 and/or replenishment of arginine may be important in preventing/treating severe COVID-19.

The Functional Diversity of Nitric Oxide Synthase Isoforms in Human Nose and Paranasal Sinuses: Contrasting Pathophysiological Aspects in Nasal Allergy and Chronic Rhinosinusitis.

The human paranasal sinuses are the major source of intrinsic nitric oxide (NO) production in the human airway. NO plays several roles in the maintenance of physiological homeostasis and the regulation of airway inflammation through the expression of three NO synthase (NOS) isoforms. Measuring NO levels can contribute to the diagnosis and assessment of allergic rhinitis (AR) and chronic rhinosinusitis (CRS). In symptomatic AR patients, pro-inflammatory cytokines upregulate the expression of inducible NOS (iNOS) in the inferior turbinate. Excessive amounts of NO cause oxidative damage to cellular components, leading to the deposition of cytotoxic substances. CRS phenotype and endotype classifications have provided insights into modern treatment strategies. Analyses of the production of sinus NO and its metabolites revealed pathobiological diversity that can be exploited for useful biomarkers. Measuring nasal NO based on different NOS activities is a potent tool for specific interventions targeting molecular pathways underlying CRS endotype-specific inflammation. We provide a comprehensive review of the functional diversity of NOS isoforms in the human sinonasal system in relation to these two major nasal disorders' pathologies. The regulatory mechanisms of NOS expression associated with the substrate bioavailability indicate the involvement of both type 1 and type 2 immune responses.