First-hit SETBP1 mutations cause a myeloproliferative disorder with bone marrow fibrosis

ABSTRACT

SETBP1 mutations are found in various clonal myeloid disorders. However, it is unclear whether they can initiate leukemia, because SETBP1 mutations typically appear as later events during oncogenesis. To answer this question, we generated a mouse model expressing mutated SETBP1 in hematopoietic tissue: this model showed profound alterations in the differentiation program of hematopoietic progenitors and developed a myeloid neoplasm with megakaryocytic dysplasia, splenomegaly, and bone marrow fibrosis, prompting us to investigate SETBP1 mutations in a cohort of 36 triple-negative primary myelofibrosis (TN-PMF) cases. We identified 2 distinct subgroups, one carrying SETBP1 mutations and the other completely devoid of somatic variants. Clinically, a striking difference in disease aggressiveness was noted, with patients with SETBP1 mutation showing a much worse clinical course. In contrast to myelodysplastic/myeloproliferative neoplasms, in which SETBP1 mutations are mostly found as a late clonal event, single-cell clonal hierarchy reconstruction in 3 patients with TN-PMF from our cohort revealed SETBP1 to be a very early event, suggesting that the phenotype of the different SETBP1+ disorders may be shaped by the opposite hierarchy of the same clonal SETBP1 variants.

Idiopathic erythrocytosis: a germline disease?

Polycythemia Vera (PV) is typically caused by V617F or exon 12 JAK2 mutations. Little is known about Polycythemia cases where no JAK2 variants can be detected, and no other causes identified. This condition is defined as idiopathic erythrocytosis (IE). We evaluated clinical-laboratory parameters of a cohort of 56 IE patients and we determined their molecular profile at diagnosis with paired blood/buccal-DNA exome-sequencing coupled with a high-depth targeted OncoPanel to identify a possible underling germline or somatic cause. We demonstrated that most of our cohort (40/56: 71.4%) showed no evidence of clonal hematopoiesis, suggesting that IE is, in large part, a germline disorder. We identified 20 low mutation burden somatic variants (Variant allelic fraction, VAF, < 10%) in only 14 (25%) patients, principally involving DNMT3A and TET2. Only 2 patients presented high mutation burden somatic variants, involving DNMT3A, TET2, ASXL1 and WT1. We identified recurrent germline variants in 42 (75%) patients occurring mainly in JAK/STAT, Hypoxia and Iron metabolism pathways, among them: JAK3-V722I and HIF1A-P582S; a high fraction of patients (48.2%) resulted also mutated in homeostatic iron regulatory gene HFE-H63D or C282Y. By generating cellular models, we showed that JAK3-V722I causes activation of the JAK-STAT5 axis and upregulation of EPAS1/HIF2A, while HIF1A-P582S causes suppression of hepcidin mRNA synthesis, suggesting a major role for these variants in the onset of IE.

A novel de novo HCN2 loss-of-function variant causing developmental and epileptic encephalopathy treated with a ketogenic diet

Missense variants of hyperpolarization-activated, cyclic nucleotide-gated (HCN) ion channels cause variable phenotypes, ranging from mild generalized epilepsy to developmental and epileptic encephalopathy (DEE). Although variants of HCN1 are an established cause of DEE, those of HCN2 have been reported in generalized epilepsies. Here we describe the first case of DEE caused by the novel de novo heterozygous missense variant c.1379G>A (p.G460D) of HCN2. Functional characterization in transfected HEK293 cells and neonatal rat cortical neurons revealed that HCN2 p.G460D currents were strongly reduced compared to wild-type, consistent with a dominant negative loss-of-function effect. Immunofluorescence staining showed that mutant channels are retained within the cell and do not reach the membrane. Moreover, mutant HCN2 also affect HCN1 channels, by reducing the Ih current expressed by the HCN1-HCN2 heteromers. Due to the persistence of frequent seizures despite pharmacological polytherapy, the patient was treated with a ketogenic diet, with a significant and long-lasting reduction of episodes. In vitro experiments conducted in a ketogenic environment demonstrated that the clinical improvement observed with this dietary regimen was not mediated by a direct action on HCN2 activity. These results expand the clinical spectrum related to HCN2 channelopathies, further broadening our understanding of the pathogenesis of DEE.

TWIST1 Upregulation Is a Potential Target for Reversing Resistance to the CDK4/6 Inhibitor in Metastatic Luminal Breast Cancer Cells

Cyclin-dependent kinase (CDK) 4/6 inhibitors have significantly improved progression-free survival in hormone-receptor-positive (HR+), human-epidermal-growth-factor-receptor-type-2-negative (HER2-) metastatic luminal breast cancer (mLBC). Several studies have shown that in patients with endocrine-sensitive or endocrine-resistant LBC, the addition of CDK4/6 inhibitors to endocrine therapy significantly prolongs progression-free survival. However, the percentage of patients who are unresponsive or refractory to these therapies is as high as 40%, and no reliable and reproducible biomarkers have been validated to select a priori responders or refractory patients. The selection of mutant clones in the target oncoprotein is the main cause of resistance. Other mechanisms such as oncogene amplification/overexpression or mutations in other pathways have been described in several models. In this study, we focused on palbociclib, a selective CDK4/6 inhibitor. We generated a human MCF-7 luminal breast cancer cell line that was able to survive and proliferate at different concentrations of palbociclib and also showed cross-resistance to abemaciclib. The resistant cell line was characterized via RNA sequencing and was found to strongly activate the epithelial-to-mesenchymal transition. Among the top deregulated genes, we found a dramatic downregulation of the CDK4 inhibitor CDKN2B and an upregulation of the TWIST1 transcription factor. TWIST1 was further validated as a target for the reversal of palbociclib resistance. This study provides new relevant information about the mechanisms of resistance to CDK4/6 inhibitors and suggests potential new markers for patients' follow-up care during treatment.

Antibody Deficiency in Patients with Biallelic KARS1 Mutations

Biallelic KARS1 mutations cause KARS-related diseases, a rare syndromic condition encompassing central and peripheral nervous system impairment, heart and liver disease, and deafness. KARS1 encodes the t-RNA synthase of lysine, an aminoacyl-tRNA synthetase, involved in different physiological mechanisms (such as angiogenesis, post-translational modifications, translation initiation, autophagy and mitochondrial function). Although patients with immune-hematological abnormalities have been individually described, results have not been collectively discussed and functional studies investigating how KARS1 mutations affect B cells have not been performed. Here, we describe one patient with severe developmental delay, sensoneurinal deafness, acute disseminated encephalomyelitis, hypogammaglobulinemia and recurrent infections. Pathogenic biallelic KARS1 variants (Phe291Val/ Pro499Leu) were associated with impaired B cell metabolism (decreased mitochondrial numbers and activity). All published cases of KARS-related diseases were identified. The corresponding authors and researchers involved in the diagnosis of inborn errors of immunity or genetic syndromes were contacted to obtain up-to-date clinical and immunological information. Seventeen patients with KARS-related diseases were identified. Recurrent/severe infections (9/17) and B cell abnormalities (either B cell lymphopenia [3/9], hypogammaglobulinemia [either IgG, IgA or IgM; 6/15] or impaired vaccine responses [4/7]) were frequently reported. Immunoglobulin replacement therapy was given in five patients. Full immunological assessment is warranted in these patients, who may require detailed investigation and specific supportive treatment.

Effects of blocking CD24 and CD47 'don't eat me' signals in combination with rituximab in mantle-cell lymphoma and chronic lymphocytic leukaemia

Mantle-cell lymphoma (MCL) is a B-cell non-Hodgkin Lymphoma (NHL) with a poor prognosis, at high risk of relapse after conventional treatment. MCL-associated tumour microenvironment (TME) is characterized by M2-like tumour-associated macrophages (TAMs), able to interact with cancer cells, providing tumour survival and resistance to immuno-chemotherapy. Likewise, monocyte-derived nurse-like cells (NLCs) present M2-like profile and provide proliferation signals to chronic lymphocytic leukaemia (CLL), a B-cell malignancy sharing with MCL some biological and phenotypic features. Antibodies against TAMs targeted CD47, a 'don't eat me' signal (DEMs) able to quench phagocytosis by TAMs within TME, with clinical effectiveness when combined with Rituximab in pretreated NHL. Recently, CD24 was found as valid DEMs in solid cancer. Since CD24 is expressed during B-cell differentiation, we investigated and identified consistent CD24 in MCL, CLL and primary human samples. Phagocytosis increased when M2-like macrophages were co-cultured with cancer cells, particularly in the case of paired DEMs blockade (i.e. anti-CD24 + anti-CD47) combined with Rituximab. Similarly, unstimulated CLL patients-derived NLCs provided increased phagocytosis when DEMs blockade occurred. Since high levels of CD24 were associated with worse survival in both MCL and CLL, anti-CD24-induced phagocytosis could be considered for future clinical use, particularly in association with other agents such as Rituximab.

Conditioned Medium of Mesenchymal Stromal Cells Loaded with Paclitaxel Is Effective in Preclinical Models of Triple-Negative Breast Cancer (TNBC)

Triple-negative breast cancer (TNBC) is a very aggressive disease even in its early stages and is characterized by a severe prognosis. Neoadjuvant chemotherapy is one of the milestones of treatment, and paclitaxel (PTX) is among the most active drugs used in this setting. However, despite its efficacy, peripheral neuropathy occurs in approximately 20-25% of cases and represents the dose-limiting toxicity of this drug. New deliverable strategies to ameliorate drug delivery and reduce side effects are keenly awaited to improve patients' outcomes. Mesenchymal stromal cells (MSCs) have recently been demonstrated as promising drug delivery vectors for cancer treatment. The aim of the present preclinical study is to explore the possibility of a cell therapy approach based on the use of MSCs loaded with PTX to treat TNBC-affected patients. For this purpose, we in vitro evaluated the viability, migration and colony formation of two TNBC cell lines, namely, MDA-MB-231 and BT549, treated with MSC-PTX conditioned medium (MSC-CM PTX) in comparison with both CM of MSCs not loaded with PTX (CTRL) and free PTX. We observed stronger inhibitory effects on survival, migration and tumorigenicity for MSC-CM PTX than for CTRL and free PTX in TNBC cell lines. Further studies will provide more information about activity and potentially open the possibility of using this new drug delivery vector in the context of a clinical study.

AB1101 PREVALENCE OF LONG COVID IN RHEUMATIC DISEASE PATIENTS: ANALYSIS OF SAR COVID REGISTRY

Background

Persistent symptoms after acute COVID have been described previously. Main symptoms reported are fatigue, arthralgias, myalgias and mental sickness. Definition and methods vary widely.1

Objectives

To asses prevalence and related factors to long COVID in a retrospective cohort of patients with rheumatic diseases from Argentina.

Methods

A total of 1915 patients were registered from August 18th, 2020 to July 29th, 2021. Patients > 18 years old, with rheumatic disease and confirmed infection by SARS-CoV-2 (antigen or RT-PCR) were included. Those dead, with unknown outcome, wrong date or missing data were excluded. Demographic data, comorbidities, rheumatic disease, and characteristics of SARS-CoV-2 infection were recorded.

Long COVID was defined according to NICE guidelines (persistent symptoms for more than 4 weeks, without alternative diagnosis). Long COVID symptoms were defined by rheumatologist. Severity of infection was classified according to WHO ordinal scale.

We used descriptive statistics, univariate model (Student’s test, chi square test, ANOVA) and multivariate logistic regression analysis.

Results

230 (12%) had long COVID. Median age was 51 (IQR 40-61]) years, 82% were females, 51% were not caucasian. Median of education was 13.3 years (IQR 12 – 16), 79 % had private health insurance and 55 % were employed. Nearly half (n=762, 46%) had comorbidities, the most prevalent was hypertension (n=396, 24%).

The most frequent rheumatic diseases were rheumatoid arthritis (n=719, 42%) and systemic lupus erythematosus (n=280, 16 %). Most were in low activity/remission (79%), used Conventional DMARD (n=773 patients, 45%) and steroids (n=588, 34%) at low dose (n=415, 71%).

Main laboratory findings were abnormal D-dimer (n=94, 28%) and leukopenia (n=93, 26%). Most patients had a WHO ordinal scale < 5 (n=1472, 86%). Median of hospitalization at intensive care unit (ICU) was 8 days [IQR 5, 13]. Treatment for SARS-CoV-2 infection (steroids, anticoagulation, azithromycin, convalescent plasma) was used in 461 (27%) patients.

Most of long COVID (n= 152, 69%) reported 1 symptom, the most frequent was fatigue (n= 55, 22%). Figure 1.

Univariate analysis is presented in Table 1. In multivariate logistic regression analysis non-caucasian ethnicity OR 1.44 (1.07-1.95), years of education OR 1.05 (1-1.09), treatment with cyclophosphamide OR 11.35 (1.56-112.97), symptoms of COVID – 19 OR 13.26 (2.75-242.08), severity scale WHO ≥ 5 OR 2.46 (1.68-3.57), and ICU hospitalization days OR 1.09 (1.05-1.14) were factors associated to long COVID.

Table 1.

Univariate analysis of long COVID syndrome in SAR – COVID registry

VariableAcute COVID n=1486Long COVID n=221P valueAge, years, median [IQR]51 [40, 60]54 [42, 62]0.032Caucasian, n (%)744 (48)132 (53)0.227Female sex, n (%)1242 (80)215 (86)0.066Education, years, median [IQR]12 [10, 17]13 [12, 16]-Private health insurance, n (%)1161 (79)181 (82)0.325Smoking, n (%)381 (25)71 (29)0.224Comorbidities, n (%)650 (45)108 (52)0.066Dyslipidemia, n (%)173 (12)39 (19)0.008Hypertension, n (%)332 (23)60 (29)0.053Low activity/remission disease, n (%)1140 (80)179 (77)1Rheumatoid arthritis, n (%)623 (42)96 (42)1Systemic lupus erythematosus, n (%)243 (16)37 (16)0.996DMARD, n (%)664 (45)109 (47)0.486Cyclophosphamide, n (%)3 (0.2)3 (1)0.035Rituximab, n (%)19 (1)9 (34)0.008Lymphocyte66 (23)19 (30)0.011<1.500 / mm3, n (%)Ferritin > 2000 ng/ml, n (%)32 (11)16 (25)0.011ICU hospitalization, days,7 [4, 10]10 [8, 24]<0.001median [IQR]Treatment for COVID-19, n (%)394 (27)91 (41)<0.001

Conclusion

Prevalence of long COVID was 12%. Non-caucasian ethnicity, higher education, treatment with cyclophosphamide, symptoms of COVID – 19, severe disease and ICU hospitalization days were related to long COVID.

References

[1]Cabrera Martimbianco AL, Pacheco RL, Bagattini ÂM, Riera R. Frequency, signs and symptoms, and criteria adopted for long COVID-19: A systematic review. Int J Clin Pract.

Disclosure of Interests

None declared

POS1238 GLUCOCORTICOIDS, RITUXIMAB AND THE PRESENCE OF INTERSTITIAL LUNG DISEASE ARE ASSOCIATED WITH POOR OUTCOMES OF THE SARS-COV-2 INFECTION IN PATIENTS WITH RHEUMATOID ARTHRITIS: DATA FROM THE NATIONAL REGISTRY SAR-COVID

Background

High disease activity, treatment with glucocorticoids (GC) and rituximab (RTX), have been related to worse outcomes of COVID-19.

Objectives

To assess the clinical characteristics and severity of the SARS-CoV-2 infection in patients with rheumatoid arthritis (RA) included in the SAR-COVID registry and to identify factors associated with poor outcomes.

Methods

SAR-COVID is a national, longitudinal and observational registry. Patients of ≥18 years old, with diagnosis of RA (ACR-EULAR criteria 2010) who had confirmed SARS-CoV-2 infection (RT-PCR or positive serology) were included between 13-8-20 and 31-7-21. Sociodemographic and clinical data, comorbidities, disease activity and treatment at the moment of the SARS-CoV-2 infection were collected. Additionally, infection symptoms, complications, medical interventions and treatments for COVID-19 were registered. Infection severity was assessed using the WHO-ordinal scale (WHO-OS)1. A cut-off value of ≥5 identified patients with severe COVID-19 and those who died.

Statistical analysis: Descriptive statistics. Chi2 or Fischer test, Student T test or Mann-Whitney and Kruskal Wallis or ANOVA, as appropriate. Multiple logistic regression model.

Results

A total of 801 patients were included, with a mean age of 53.1 ± 12.9 years, most of them were female (84.5%) and the median (m) disease duration was 8 years (IQR 4-14). One third were in remission and 46.4% had comorbidities, being the most frequent, hypertension (26.9 %), dyslipidemia (13.5 %), obesity (13.4 %) and diabetes (8.9%). Moreover, 3.2% had interstitial lung disease (ILD) associated with RA. At SARS-CoV-2 diagnosis, 42.5% were receiving glucocorticoids (GC), 73.9% conventional (c) disease modifying antirheumatic drugs (DMARD), 24% biologic (b) DMARD and 9.1% targeted synthetic (ts) DMARD. Among bDMARD, the most frequently used were TNF inhibitors (17%), followed by abatacept (2.8%), IL-6 inhibitors (2.4%) and rituximab (RTX) (2.1%). During the SARS-CoV-2 infection, 95.8% had symptoms, 27% required hospitalization, 7.9% presented complications and 4.4% died due to COVID-19. Severe disease and death (WHO-OS≥5) was present in 7.5% of the patients. They were older (62.9±12.5 vs 52.2±12.7, p<0.001), and they had more frequently ILD (18.5% vs 2%, p<0.001), comorbidities (82.5% vs 43.7%, p<0.001), ≥2 comorbidities (60.3% vs 25.8%, p<0.001), treatment with GC (61% vs 40.7%, p=0.04) and RTX (8.3% vs 1.6%, p=0.007). Conversely, the use of cDMARD and TNF inhibitors was more frequent in patients with WHO-OS<5, nevertheless this difference was not significant. Disease activity was comparable between groups. In multivariable analysis, older age, the presence of diabetes, ILD, the use of GC and RTX were significantly associated with WHO-OS≥5 (Figure 1). Furthermore, older age (65.7±10.8 vs 52.4±12.8, p<0.001), the presence of comorbidities (87.9% vs 44.7%, p<0.001), chronic obstructive pulmonary disease (21.9% vs 5.2%, p=0.002), diabetes (30.3% vs 7.9%, p<0.001), hypertension (57.6% vs 25.6%, p<0.001), cardiovascular disease (15.6% vs 3.2%, p=0.005), cancer (9.1% vs 1.3%, p=0.001), ILD (23.3% vs 2.4%, p<0.001) and the use of GC (61.8% vs 41.4%, p=0.02) were associated with mortality. Older age [OR 1.1 IC95% 1.06-1.13] and the use of GC 5-10 mg/day [OR 4.6 IC95% 1.8-11.6] remained significantly associated with death due to COVID-19.

Figure 1.

Factors associated with severe disease and death due to COVID-19 (WHO-OS≥5) in patients with rheumatoid arthritis. Multivariable analysis. (ref.: reference; PDN: prednisone; OR: odds ratio; CI: confidence interval)

Conclusion

Treatment with RTX and GC, as well as older age, the presence of diabetes and ILD were associated with poor COVID-19 outcomes in this national cohort of patients with RA. Older patients and those taking GC had a higher mortality rate.

References

[1]World Health Organization coronavirus disease (COVID-19) Therapeutic Trial Synopsis Draft 2020.

Disclosure of Interests

None declared

Use of machine learning on clinical questionnaires data to support the diagnostic classification of Attention DeficitHyperactivity Disorder: a personalized medicine approach

Introduction

Attention Deficit / Hyperactivity Disorder (ADHD) is a highly prevalent neurodevelopmental condition characterized by inattention, motor hyperactivity and impulsivity. ADHD cognitive and behavioral presentation is characterized by a high heterogeneity (APA, 2013). Indeed, a complex diagnostic process, that considers several validated tools, is, to date, necessary.

Objectives

The main aim is to develop supervised machine learning (ML) algorithms that could be used to support the diagnostic process for ADHD, by identifying the most relevant features in discriminating between the presence or absence of the ADHD diagnosis in children.

Methods

We analyzed data from 342 children (Mean age: 8y 8m ± 1y; 61 F) referred for possible ADHD symptomatology. Assessments were performed by an expert clinician and through questionnaires: Social Responsiveness Scale (SRS), Child Behavior Checklist (CBCL), Conners Rating Scale for Parents (CPRS) and for Teachers (CTRS). Data were analyzed using a decision tree classifier and random forest algorithms.

Results

The decision tree model performed an accuracy of 0.71. The random forest model that was identified as the best tested, performed an accuracy of 0.77 (Figure 1) and it identified as most informative parent- and teacher-rated DSM-oriented ADHD symptoms (Figure 2).

Figure 1: Random forest confusion matrix and statistics.

Figure 2: Ranking of variables importance.

Conclusions

A random forest classifier could represent an effective algorithm to support the identification of ADHD children and to simplify the diagnostic process as an initial step. The use of supervised machine learning algorithms could be useful in helping the diagnostic process, highlighting the importance of a personalized medicine approach.

Disclosure

No significant relationships.

NIRS Hemodynamic Response to Methylphenidate in Children with Attention Aeficit Hyperactivity Disorder: First Administration, Titration Phase and Associations with Clinical Severity

Introduction

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by lack of self-regulation and deficits in organizing behaviors in response to emotional stimuli. Methylphenidate (MPH) is one of the most effective psychostimulant drugs for ADHD, however, a possible predictive utility of brain hemodynamic data related to MPH administration and its relation to clinical symptomatology is still not clear. To address these questions, we used Near Infrared Spectroscopy (NIRS) technology, a non-invasive optical technique that allows to investigate the effect of psychopharmacological treatment on cortical hemodynamics.

Methods

Twenty children with ADHD underwent a three-waves study and 25 healthy controls were recruited at W1. At W2 children with ADHD received first MPH administration and at W3 they reached the titration phase. At each phase children performed - during NIRS recording - an emotional continuous performance task with visual stimuli of different emotional content. Clinical data were also collected at W1 and W3. We investigated the relationship among the difference between NIRS activation at W2 and W1 (Delta1) and W3 and W2 (Delta2), for each subject, task condition and brain region. Lastly, we investigated correlations between the Delta1 and clinical symptomatology indexes at W1 and between Delta2 and clinical data at W3.

Conclusions

Our study results suggest that hemodynamic changes in right prefrontal region probably induced by first MPH administration could predict hemodynamic changes related to MPH titration phase. These biological indexes could be associated to clinical evidences related not only to core ADHD symptoms but also to affective correlates.

Disclosure

No significant relationships.

Prevalence and features of delirium in older patients admitted to rehabilitation facilities: a multicenter study

BACKGROUND

Delirium is thought to be common across various settings of care; however, still little research has been conducted in rehabilitation.

AIM

We investigated the prevalence of delirium, its features and motor subtypes in older patients admitted to rehabilitation facilities during the three editions of the "Delirium Day project".

METHODS

We conducted a cross-sectional study in which 1237 older patients (age ≥ 65 years old) admitted to 50 Italian rehabilitation wards during the three editions of the "Delirium Day project" (2015 to 2017) were included. Delirium was evaluated through the 4AT and its motor subtype with the Delirium Motor Subtype Scale.

RESULTS

Delirium was detected in 226 patients (18%), and the most recurrent motor subtype was mixed (37%), followed by hypoactive (26%), hyperactive (21%) and non-motor one (16%). In a multivariate Poisson regression model with robust variance, factors associated with delirium were: disability in basic (PR 1.48, 95%CI: 1.17-1.9, p value 0.001) and instrumental activities of daily living (PR 1.58, 95%CI: 1.08-2.32, p value 0.018), dementia (PR 2.10, 95%CI: 1.62-2.73, p value < 0.0001), typical antipsychotics (PR 1.47, 95%CI: 1.10-1.95, p value 0.008), antidepressants other than selective serotonin reuptake inhibitors (PR 1.3, 95%CI: 1.02-1.66, p value 0.035), and physical restraints (PR 2.37, 95%CI: 1.68-3.36, p value < 0.0001).

CONCLUSION

This multicenter study reports that 2 out 10 patients admitted to rehabilitations had delirium on the index day. Mixed delirium was the most prevalent subtype. Delirium was associated with unmodifiable (dementia, disability) and modifiable (physical restraints, medications) factors. Identification of these factors should prompt specific interventions aimed to prevent or mitigate delirium.

Large-Scale Analysis of SARS-CoV-2 Synonymous Mutations Reveals the Adaptation to the Human Codon Usage During the Virus Evolution

Many large national and transnational studies have been dedicated to the analysis of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) genome, most of which focused on missense and nonsense mutations. However, approximately 30 per cent of the SARS-CoV-2 variants are synonymous, therefore changing the target codon without affecting the corresponding protein sequence.

By performing a large-scale analysis of sequencing data generated from almost 400,000 SARS-CoV-2 samples, we show that silent mutations increasing the similarity of viral codons to the human ones tend to fixate in the viral genome overtime. This indicates that SARS-CoV-2 codon usage is adapting to the human host, likely improving its effectiveness in using the human aminoacyl-tRNA set through the accumulation of deceitfully neutral silent mutations.

One-Sentence Summary. Synonymous SARS-CoV-2 mutations related to the activity of different mutational processes may positively impact viral evolution by increasing its adaptation to the human codon usage.

Lagrangian Fibrations

We review the theory of Lagrangian fibrations of hyperkähler manifolds as initiated by Matsushita. We also discuss more recent work of Shen-Yin and Harder-Li-Shen-Yin. Occasionally, we give alternative arguments and complement the discussion by additional observations.

The association between low skeletal muscle mass and delirium: results from the nationwide multi-centre Italian Delirium Day 2017

Introduction

Delirium and sarcopenia are common, although underdiagnosed, geriatric syndromes. Several pathological mechanisms can link delirium and low skeletal muscle mass, but few studies have investigated their association. We aimed to investigate (1) the association between delirium and low skeletal muscle mass and (2) the possible role of calf circumference mass in finding cases with delirium.

Methods

The analyses were conducted employing the cross-sectional “Delirium Day” initiative, on patient 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes and hospices in Italy in 2017. Delirium was diagnosed as a 4 + score at the 4-AT scale. Low skeletal muscle mass was operationally defined as calf circumference ≤ 34 cm in males and ≤ 33 cm in females. Logistic regression models were used to investigate the association between low skeletal muscle mass and delirium. The discriminative ability of calf circumference was evaluated using non-parametric ROC analyses.

Results

A sample of 1675 patients was analyzed. In total, 73.6% of participants had low skeletal muscle mass and 24.1% exhibited delirium. Low skeletal muscle mass and delirium showed an independent association (OR: 1.50; 95% CI 1.09–2.08). In the subsample of patients without a diagnosis of dementia, the inclusion of calf circumference in a model based on age and sex significantly improved its discriminative accuracy [area under the curve (AUC) 0.69 vs 0.57, p < 0.001].

Discussion and conclusion

Low muscle mass is independently associated with delirium. In patients without a previous diagnosis of dementia, calf circumference may help to better identify those who develop delirium.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40520-021-01950-8.

Synergistic Drug Combinations Prevent Resistance in ALK+ Anaplastic Large Cell Lymphoma

Simple Summary

Despite success of targeted therapy, cancer cells very often find a way to survive treatment; this eventually causes a tumor to relapse. In a particular type of lymphoma carrying a specific chromosomal rearrangement named anaplastic large-cell lymphoma (ALCL), selective drugs targeting the cause of the disease can induce spectacular remission of chemotherapy-resistant cancer. However, the lymphoma relapses again in about half of the cases, leaving no therapeutic options. We studied the possibility to combine two simultaneous treatments in order to prevent the relapse, starting from the hypothesis that acquiring resistance to two drugs at the same time is statistically very unlikely. We demonstrate that treating lymphoma cells with drug combinations has superior efficacy in comparison with single drug treatments, both in cell cultures and in mice.

Abstract

Anaplastic lymphoma kinase-positive (ALK+) anaplastic large-cell lymphoma (ALCL) is a subtype of non-Hodgkin lymphoma characterized by expression of the oncogenic NPM/ALK fusion protein. When resistant or relapsed to front-line chemotherapy, ALK+ ALCL prognosis is very poor. In these patients, the ALK inhibitor crizotinib achieves high response rates, however 30–40% of them develop further resistance to crizotinib monotherapy, indicating that new therapeutic approaches are needed in this population. We here investigated the efficacy of upfront rational drug combinations to prevent the rise of resistant ALCL, in vitro and in vivo. Different combinations of crizotinib with CHOP chemotherapy, decitabine and trametinib, or with second-generation ALK inhibitors, were investigated. We found that in most cases combined treatments completely suppressed the emergence of resistant cells and were more effective than single drugs in the long-term control of lymphoma cells expansion, by inducing deeper inhibition of oncogenic signaling and higher rates of apoptosis. Combinations showed strong synergism in different ALK-dependent cell lines and better tumor growth inhibition in mice. We propose that drug combinations that include an ALK inhibitor should be considered for first-line treatments in ALK+ ALCL.

Abstract 1113: Synergistic drug combinations prevent drug resistance in anaplastic large cell lymphoma preclinical models

Neoplastic cells are characterized by genetic instability, leading to the random accumulation of mutations in different tumor subpopulations, which therefore respond differently to treatments. Given the average mutational rate of tumors, the probability to acquire resistance to a single drug usually exceeds the number of cells present at diagnosis, making drug resistance a fact in most cases. Statistically, the chance of a cell being resistant to two simultaneous treatments is much lower, suggesting that drug combinations may help prevent resistance.

Anaplastic large cell lymphoma (ALCL) is an aggressive type of Non-Hodgkin Lymphoma, characterized by expression of the NPM/ALK oncogenic fusion tyrosine kinase. ALK+ ALCL patients resistant or relapsed (R/R) to front-line chemotherapy have a very poor prognosis. The therapeutic activity of the ALK inhibitor crizotinib has been shown in patients with R/R ALK+ ALCL. However, 30-40% of patients develop resistance to crizotinib monotherapy and relapse within short time, leaving no further therapeutic option than bone marrow transplant, when feasible. This highlights the need to identify new first-line therapies for high-risk patients.We explored the potential of upfront drug combinations to prevent the rise of resistant disease, in vitro and in vivo. Crizotinib was combined with CHOP chemotherapy, an epigenetic drug (decitabine), another targeted inhibitor (trametinib- MEK inhibitor), or a second-generation ALK inhibitor. ALK+ ALCL cells were kept in culture for ~100 days in the presence of different single or combined drugs. We found that in most cases, combined treatments were more effective than single agents in the long-term control of cells expansion. Upon further functional characterization using quantitative PCR and western blot, we found that combination treatments upregulated cell cycle inhibitors and pro-apoptotic genes as well as modulated survival factors to induce deeper inhibition of oncogenic signalling and higher rates of apoptosis. Crizotinib+decitabine combination treatment promoted downregulation of DNMT1 and increase of TGFB1, both of which indirectly affect cell cycle progression. In murine model, crizotinib+decitabine significantly delayed tumour growth, compared to single treatments. Our results indicate that combining a selective drug with a less specific anticancer agent, which allows unspecific killing of resistant clones that might potentially arise, would be beneficial.In conclusion, our data suggest that a polypharmacology approach combining ALK inhibition with other agents could be a valuable therapeutic option for ALK+ ALCL patients, to prevent relapses and improve outcomes.

Citation Format: Geeta G. Sharma, Giulia Arosio, Matteo Villa, Mario Mauri, Marina Zappa, Vera Magistroni, Monica Ceccon, Sara Redaelli, Ilaria Crespiatico, Diletta Fontana, Cristina Mastini, Anna Garbin, Federica Lovisa, Lara Mussolin, Rocco Piazza, Carlo Gambacorrti-Passerini, Luca Mologni. Synergistic drug combinations prevent drug resistance in anaplastic large cell lymphoma preclinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1113.

Associations between genes methylation, postnatal risk factors and psychiatric symptoms in a clinical sample of children and adolescents: Preliminar results from the remind longitudinal study

Introduction

Epigenetics hypothesizes a crucial link between postnatal risk factors, individual response to stress, DNA methylation and psychiatric symptomatology changes during life.

Objectives

We analyzed methylation within two gene exons: NR3C1 and SLC6A4, which are involved in responses to environmental stressors. We investigated the relationship between methylation, postnatal risk factors and psychopathology assessed by Child Behavior Checklist (CBCL) in our help-seeking sample evaluated in infancy (W1), preadolescence (W2) and adult life (W3).

Methods

Postnatal risk factors data were collected at W1 in 205 clinical subjects (156 M, 49 F; age=9,13±1,95). The CBCL scores were collected at W1 and W2 (W2 age=14,52±2,12). Data regarding methylation were collected at W2. At W3 we are also collecting clinical scores. A Spearman correlation coefficient was calculated between methylation percentage and clinical data at W2. The externalizing and internalizing trajectories were evaluated through repeated measure ANOVA with postnatal risk factors (presence/absence) as between-groups factor.

Results

Significant associations were found between methylation and internalizing and total clinical scores (Table 1). The rm-ANOVA results showed a significant interaction between the CBCL internalizing score and presence/absence of postnatal risk, with higher internalizing problems in subjects that were exposed to postnatal risk factors. This effect was significant at W2 but not at W1 (Figure 1).

Conclusions

Psychopathological symptoms trajectories could depend on epigenetics and early environmental risk factors. Further analyses will address a Linear Discriminant Analysis to proceed to a machine learning oriented approach.

Disclosure

No significant relationships.

Relationship between internalizing and externalizing symptoms trajectories and perinatal risk factors in an epidemiological sample: Preliminary results from the remind project

Introduction

Our 15-years follow-up ReMIND project aims to re-assess an epidemiological and a clinical sample of adults (Wave 3), who were assessed in preadolescence (Wave 1) and adolescence (Wave 2), to evaluate symptoms trajectories and their relationship with genetic/epigenetic data, environmental risk factors and neuroimaging measures.

Objectives

Here, we depict preliminary results regarding the epidemiological sample.

Methods

We assessed internalizing and externalizing symptoms in 40 italian subjects (25 F) from general population at three waves (W1 mean age: 12±0,82; W2 mean age: 17±0,88, W3 mean age: 28±1), through the Child Behavior Checklist (W1 and W2) or the Adult Self Report (W3), and perinatal risk factors through a socio-anamnestic questionnaire, by a new online platform (MedicalBit). We analyzed symptoms trajectories and their relation with perinatal risk factors through a repeated measures multivariate analysis of variance (rm-MANOVA).

Results

rm-MANOVA results show that high number of perinatal risks was significantly associated with higher internalizing symptomatology in preadolescence but not in adolescence and adult life. The mean difference was 8 T-points. The same trend is evident in adolescence but not in adult age (Graph 1). Perinatal risk factors did not have a significant effect on externalizing symptoms at any time point, despite a non-significant trend is evident (Graph 2).

Conclusions

Our preliminary results suggest a trend of increased internalizing symptoms from childhood to adulthood and a significant role of perinatal risk factors in pre-adolescence. Further investigations are necessary to better understand symptoms trajectories and the role of biological and environmental factors.

Disclosure

No significant relationships.

Absent B cells, agammaglobulinemia, and hypertrophic cardiomyopathy in folliculin-interacting protein 1 deficiency

Agammaglobulinemia is the most profound primary antibody deficiency that can occur due to an early termination of B-cell development. We here investigated 3 novel patients, including the first known adult, from unrelated families with agammaglobulinemia, recurrent infections, and hypertrophic cardiomyopathy (HCM). Two of them also presented with intermittent or severe chronic neutropenia. We identified homozygous or compound-heterozygous variants in the gene for folliculin interacting protein 1 (FNIP1), leading to loss of the FNIP1 protein. B-cell metabolism, including mitochondrial numbers and activity and phosphatidylinositol 3-kinase/AKT pathway, was impaired. These defects recapitulated the Fnip1-/- animal model. Moreover, we identified either uniparental disomy or copy-number variants (CNVs) in 2 patients, expanding the variant spectrum of this novel inborn error of immunity. The results indicate that FNIP1 deficiency can be caused by complex genetic mechanisms and support the clinical utility of exome sequencing and CNV analysis in patients with broad phenotypes, including agammaglobulinemia and HCM. FNIP1 deficiency is a novel inborn error of immunity characterized by early and severe B-cell development defect, agammaglobulinemia, variable neutropenia, and HCM. Our findings elucidate a functional and relevant role of FNIP1 in B-cell development and metabolism and potentially neutrophil activity.

HIF1A: A Putative Modifier of Hemochromatosis

HFE-related hereditary hemochromatosis (HH) is characterized by marked phenotypic heterogeneity. Homozygosity for p.C282Y is a low penetrance genotype suggesting that the HFE-HH is a multifactorial disease resulting from a complex interaction involving a major gene defect, genetic background and environmental factors. We performed a targeted NGS-based gene panel to identify new candidate modifiers by using an extreme phenotype sampling study based on serum ferritin and iron removed/age ratio. We found an increased prevalence of the HIF1A p.Phe582Ser and p.Ala588Thr variants in patients with a severe iron and clinical phenotype. Accordingly, Huh-7 cells transfected with both variants showed significantly lower HAMP promoter activity by luciferase assay. The qRT-PCR assays showed a downregulation of hepcidin and an upregulation of the HIF1A target genes (VEGF, HMOX, FUR, TMPRSS6) in cells transfected with the HIF1A-P582S vector. We identified mutations in other genes (e.g., Serpina1) that might have some relevance in single cases in aggravating or mitigating disease manifestation. In conclusion, the present study identified HIF1A as a possible modifier of the HFE-HH phenotype cooperating with the genetic defect in downregulating hepcidin synthesis. In addition, this study highlights that an NGS-based approach could broaden our knowledge and help in characterizing the genetic complexity of HFE-HH patients with a severe phenotype expression.

Case Report: Hypomorphic Function and Somatic Reversion in DOCK8 Deficiency in One Patient With Two Novel Variants and Sclerosing Cholangitis

DOCK8 deficiency is a combined immunodeficiency due to biallelic variants in dedicator of cytokinesis 8 (DOCK8) gene. The disease has a wide clinical spectrum encompassing recurrent infections (candidiasis, viral and bacterial infections), virally driven malignancies and immune dysregulatory features, including autoimmune (cytopenia and vasculitis) as well as allergic disorders (eczema, asthma, and food allergy). Hypomorphic function and somatic reversion of DOCK8 has been reported to result in incomplete phenotype without IgE overproduction. Here we describe a case of DOCK8 deficiency in a 8-year-old Caucasian girl. The patient's disease was initially classified as autoimmune thrombocytopenia, which then evolved toward a combined immunodeficiency phenotype with recurrent infections, persistent EBV infection and lymphoproliferation. Two novel variants (one deletion and one premature stop codon) were characterized, resulting in markedly reduced, but not absent, DOCK8 expression. Somatic reversion of the DOCK8 deletion was identified in T cells. Hypomorphic function and somatic reversion were associated with restricted T cell repertoire, decreased STAT5 phosphorylation and impaired immune synapse functioning in T cells. Although the patient presented with incomplete phenotype (absence of markedly increase IgE and eosinophil count), sclerosing cholangitis was incidentally detected, thus indicating that hypomorphic function and somatic reversion of DOCK8 may delay disease progression but do not necessarily prevent from severe complications.

ETNK1 mutations induce a mutator phenotype that can be reverted with phosphoethanolamine

Recurrent somatic mutations in ETNK1 (Ethanolamine-Kinase-1) were identified in several myeloid malignancies and are responsible for a reduced enzymatic activity. Here, we demonstrate in primary leukemic cells and in cell lines that mutated ETNK1 causes a significant increase in mitochondrial activity, ROS production, and Histone H2AX phosphorylation, ultimately driving the increased accumulation of new mutations. We also show that phosphoethanolamine, the metabolic product of ETNK1, negatively controls mitochondrial activity through a direct competition with succinate at mitochondrial complex II. Hence, reduced intracellular phosphoethanolamine causes mitochondria hyperactivation, ROS production, and DNA damage. Treatment with phosphoethanolamine is able to counteract complex II hyperactivation and to restore a normal phenotype.

Intranasal delivery of mesenchymal stem cell-derived extracellular vesicles exerts immunomodulatory and neuroprotective effects in a 3xTg model of Alzheimer's disease

The critical role of neuroinflammation in favoring and accelerating the pathogenic process in Alzheimer's disease (AD) increased the need to target the cerebral innate immune cells as a potential therapeutic strategy to slow down the disease progression. In this scenario, mesenchymal stem cells (MSCs) have risen considerable interest thanks to their immunomodulatory properties, which have been largely ascribed to the release of extracellular vesicles (EVs), namely exosomes and microvesicles. Indeed, the beneficial effects of MSC-EVs in regulating the inflammatory response have been reported in different AD mouse models, upon chronic intravenous or intracerebroventricular administration. In this study, we use the triple-transgenic 3xTg mice showing for the first time that the intranasal route of administration of EVs, derived from cytokine-preconditioned MSCs, was able to induce immunomodulatory and neuroprotective effects in AD. MSC-EVs reached the brain, where they dampened the activation of microglia cells and increased dendritic spine density. MSC-EVs polarized in vitro murine primary microglia toward an anti-inflammatory phenotype suggesting that the neuroprotective effects observed in transgenic mice could result from a positive modulation of the inflammatory status. The possibility to administer MSC-EVs through a noninvasive route and the demonstration of their anti-inflammatory efficacy might accelerate the chance of a translational exploitation of MSC-EVs in AD.

Abstract 4715: Characterization of potential co-drivers of pathogenesis in ALK positive ALCL

ALK positive Anaplastic large cell lymphoma (ALCL) is an aggressive non-Hodgkin lymphoma characterized by expression of the NPM/ALK fusion tyrosine kinase essential for neoplastic cells growth. When resistant or relapsed to front-line chemotherapy, ALK+ ALCL prognosis is very poor. Although ALK+ ALCL cells are mainly driven by the constitutively active NPM/ALK kinase, presence of additional mutations might affect the disease course and response to treatment, leading to different outcomes in different patients. We employed whole exome sequencing to characterize the co-mutational burden in ALK+ ALCL samples at diagnosis. Diagnosis biopsy and matched healthy control DNA samples from 24 ALK+ ALCL patients were sequenced. Somatic variants present at high frequency within the tumor (at least 25% variant allele frequency), which can be viewed as potential co-drivers, were annotated; the identified mutations were weighed using in silico tools to predict their oncogenic potential and their effects on protein function. All identified variants were confirmed by Sanger sequencing. Gene ontology and pathway analyses identified cell adhesion and actin cytoskeleton among the most enriched biological functions. Using the above-mentioned criteria, we found recurrent somatic variants in 7 genes including PPP1R9A, RUNX1T1, FAT4 and RBBP8. Here we report the initial characterization of the role of FAT4 in ALCL cells. FAT4 is a member of the cadherin superfamily with tumor suppressor functions. In our cohort, 3/24 patients (13%) were found to carry FAT4 mutations, including nonsense mutations and missense changes predicted to be deleterious, suggesting a loss of function effect. To characterize the biological consequences of these mutations, we generated FAT4 knockdown ALCL cell lines. FAT4-silenced cells grew faster and showed increased migratory properties compared to parental cells. They also differed from parental cells in terms of morphology, having bigger size and modulated F-actin rearrangement. Tumor suppressing activity of FAT4 has been linked to Wnt/β-catenin pathway; we found that FAT4-silenced cells had decreased levels of serine/threonine phosphorylated β-catenin and higher nuclear localization, which insinuates activation of Wnt/β-catenin signalling and henceforth, increased cellular proliferation. To explore therapeutic implications of FAT4 mutations, we analyzed the sensitivity of FAT4 silenced cells to chemotherapeutic agents. FAT4 knockdown cells were less sensitive to a CHOP combination treatment as compared to parental cells. No difference was seen in terms of sensitivity to crizotinib. Finally, we investigated the effects of RUNX1T1 somatic variants found in our study. Preliminary luciferase assay results showed that the variants significantly increase the transcriptional repression ability of RUNX1T1. Altogether, our data provides information about genes other than NPM-ALK that might play a role in the pathogenesis of ALCL.

Citation Format: Luca Mologni, Geeta G. Sharma, Matteo Villa, Mario Mauri, Giulia Arosio, Cosimo Lobello, Hugo Larose, Alessandra Pirola, Silvia Bombelli, Nicoletta Cordani, Luca Massimino, Šárka Pospíšilová, Suzanne D. Turner, Giorgio Inghirami, Fabio Pagni, Rocco Piazza, Roberto Perego, Roberto Chiarle, Carlo Gambacorti-Passerini. Characterization of potential co-drivers of pathogenesis in ALK positive ALCL [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4715.

Pressing Issues in COVID-19: Probable Cause to Seize SARS-CoV-2 for Its Preferential Involvement of Posterior Circulation Manifesting as Severe Posterior Reversible Encephalopathy Syndrome and Posterior Strokes

Since December 2019, a novel Severe Acute Respiratory Syndrome coronavirus 2 from China has rapidly spread worldwide. Although respiratory involvement is the mainstay of coronavirus disease 2019 (COVID-19), systemic involvement has recently drawn more attention. In particular, a number of recent articles have shed light on the nervous system as one of the possible targets. At our institution, we observed 15 patients with acute brain vascular manifestations; most interesting, we had a higher prevalence of the posterior circulation acute impairment. In our series, 7 patients had acute posterior cerebral injury: 1, hemorrhagic posterior reversible encephalopathy syndrome; 5, posterior circulation ischemic stroke; and 1, parieto-occipital hemorrhagic stroke. On the basis of our evidence and previous basic science reports, we believe a common etiopathogenetic thread may connect ischemic/hemorrhagic events of the posterior circulation and posterior reversible encephalopathy syndrome in the setting of COVID-19.

Lamotrigine induced Brugada-pattern in a patient with genetic epilepsy associated with a novel variant in SCN9A

BACKGROUND

A 30-year-old man presented with intellectual disability associated with epilepsy. The epilepsy was initially treated with sodium valproate and since he was 28 years-old with lamotrigine. With the addition of lamotrigine, a pattern of Brugada syndrome appeared on the electrocardiogram. The family history was positive for epilepsy from the motheŕs side, who had never been treated with lamotrigine.

OBJECTIVE

Determine the genetic cause of the intellectual disability, epilepsy and Brugada syndrome of the patient and try to establish a possible correlation between the genetic background and the Brugada syndrome pattern under lamotrigine treatment.

METHODS

A standard karyotype, array comparative genomic hybridization and two different NGS panels have done to the index case to identify the genetic causes of the intellectual disability, epilepsy and Brugada syndrome pattern.

RESULTS

Genetic analyses in the family identified a de novo duplication of 1.3 Mb in 8p21.3 as well as two novel heterozygous rare variants in SCN9A and AKAP9 genes, both inherited from the mother.

CONCLUSION

We hypothesize that in this family the SCN9A variant was responsible for the epileptic syndrome. In addition, given that SCN9A is lightly expressed in the heart tissue, we postulate that this SCN9A variant, alone or in combination with AKAP9 variant, might be responsible for the Brugada pattern when challenged by lamotrigine.

Epidemiological Study for the Evaluation of Metabolic Disorders in Patients with Schizophrenia: The Meteor Study

A large, observational, multinational cross-sectional pharmacoepidemiological study was performed to determine the prevalence of diabetes and other metabolic disorders in patients with schizophrenia receiving atypical antipsychotic drugs in Europe.

The study included adult outpatients with schizophrenia (DSM-IV-TR) treated for at least three months by an antipsychotic drug. Patients treated with classical or atypical antipsychotic drugs were recruited into two parallel strata (ratio of 1:3). A fasting blood sample was taken and height, weight, waist and hip circumference and blood pressure measured during a single visit. Biochemical parameters assessed included glucose, insulin, HbA1c, triglycerides, total cholesterol, HDL-cholesterol and apolipoprotein B.

2463 patients (median age: 41.0 years; 54.6% male) were included in twelve countries. among these, 10.9% of patients were treated for hypertension, 7.1% for a lipid disorder, 0.3% for type I diabetes and 3.5% for type II diabetes. in addition, 26% of untreated patients had dysglycaemia, 67.7% dyslipidemia and 38% had hypertension. 34% of the patients presented a metabolic syndrome. No overall difference was observed in the proportion of patients with glycaemic and lipid disorders between the two treatment strata. Values for weight-related variables were slightly higher in the atypical stratum, whereas hypertension was more frequent in the classical stratum (47.3%) than in the atypical stratum (42.2%).

The results of this study emphasise the need for careful follow-up of patients with schizophrenia treated with antipsychotic drugs to detect the occurrence of metabolic disorders. the proportion of patients with glycaemic or lipid disorders was very high and largely underdiagnosed.

This study was funded by sanofi-aventis.

Subgroup comparison according to clinical phenotype and serostatus in autoimmune encephalitis: a multicenter retrospective study

BACKGROUND AND PURPOSE

Autoimmune encephalitides (AE) include a spectrum of neurological disorders whose diagnosis revolves around the detection of neuronal antibodies (Abs). Consensus-based diagnostic criteria (AE-DC) allow clinic-serological subgrouping of AE, with unclear prognostic implications. The impact of AE-DC on patients' management was studied, focusing on the subgroup of Ab-negative-AE.

METHODS

This was a retrospective multicenter study on patients fulfilling AE-DC. All patients underwent Ab testing with commercial cell-based assays (CBAs) and, when available, in-house assays (immunohistochemistry, live/fixed CBAs, neuronal cultures) that contributed to defining final categories. Patients were classified as Ab-positive-AE [N-methyl-d-aspartate-receptor encephalitis (NMDAR-E), Ab-positive limbic encephalitis (LE), definite-AE] or Ab-negative-AE (Ab-negative-LE, probable-AE, possible-AE).

RESULTS

Commercial CBAs detected neuronal Abs in 70/118 (59.3%) patients. Testing 37/48 Ab-negative cases, in-house assays identified Abs in 11 patients (29.7%). A hundred and eighteen patients fulfilled the AE-DC, 81 (68.6%) with Ab-positive-AE (Ab-positive-LE, 40; NMDAR-E, 32; definite-AE, nine) and 37 (31.4%) with Ab-negative-AE (Ab-negative-LE, 17; probable/possible-AE, 20). Clinical phenotypes were similar in Ab-positive-LE versus Ab-negative-LE. Twenty-four/118 (20.3%) patients had tumors, and 19/118 (16.1%) relapsed, regardless of being Ab-positive or Ab-negative. Ab-positive-AE patients were treated earlier than Ab-negative-AE patients (P = 0.045), responded more frequently to treatments (92.3% vs. 65.6%, P < 0.001) and received second-line therapies more often (33.3% vs. 10.8%, P = 0.01). Delays in first-line therapy initiation were associated with poor response (P = 0.022; odds ratio 1.02; confidence interval 1.00-1.04).

CONCLUSIONS

In-house diagnostics improved Ab detection allowing better patient management but was available in a patient subgroup only, implying possible Ab-positive-AE underestimation. Notwithstanding this limitation, our findings suggest that Ab-negative-AE and Ab-positive-AE patients share similar oncological profiles, warranting appropriate tumor screening. Ab-negative-AE patients risk worse responses due to delayed and less aggressive treatments.

De novo UBE2A mutations are recurrently acquired during chronic myeloid leukemia progression and interfere with myeloid differentiation pathways

Despite the advent of tyrosine kinase inhibitors, a proportion of chronic myeloid leukemia patients in chronic phase fail to respond to imatinib or to second-generation inhibitors and progress to blast crisis. Until now, improvements in the understanding of the molecular mechanisms responsible for chronic myeloid leukemia transformation from chronic phase to the aggressive blast crisis remain limited. Here we present a large parallel sequencing analysis of 10 blast crisis samples and of the corresponding autologous chronic phase controls that reveals, for the first time, recurrent mutations affecting the ubiquitin-conjugating enzyme E2A gene (UBE2A, formerly RAD6A). Additional analyses on a cohort of 24 blast crisis, 41 chronic phase as well as 40 acute myeloid leukemia and 38 atypical chronic myeloid leukemia patients at onset confirmed that UBE2A mutations are specifically acquired during chronic myeloid leukemia progression, with a frequency of 16.7% in advanced phases. In vitro studies show that the mutations here described cause a decrease in UBE2A activity, leading to an impairment of myeloid differentiation in chronic myeloid leukemia cells.

Abstract P5-12-08: Not presented

This abstract was not presented at the conference.

Citation Format: Botticelli A, Cerbelli B, Pisano A, Naso G, Monti M, Ascierto PA, Costarelli L, Magri V, Mauri M, Pignataro MG, Campagna D, Pernazza A, Nuti M, Fortunato L, Della Rocca C, D'Amati G, Marchetti P. Not presented [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-12-08.

Quasi-thresholdless Photon Upconversion in Metal-Organic Framework Nanocrystals

Photon upconversion based on sensitized triplet-triplet annihilation ( sTTA) is considered as a promising strategy for the development of light-managing materials aimed to enhance the performance of solar devices by recovering unused low-energy photons. Here, we demonstrate that, thanks to the fast diffusion of excitons, the creation of triplet pairs in metal-organic framework nanocrystals ( nMOFs) with size smaller than the exciton diffusion length implies a 100% TTA yield regardless of the illumination condition. This makes each nMOF a thresholdless, single-unit annihilator. We develop a kinetic model for describing the upconversion dynamics in a nanocrystals ensemble, which allows us to define the threshold excitation intensity  I_th^box required to reach the maximum conversion yield. For materials based on thresholdless annihilators, I_th^box is determined by the statistical distribution of the excitation energy among nanocrystals. The model is validated by fabricating a nanocomposite material based on nMOFs, which shows efficient upconversion under a few percent of solar irradiance, matching the requirements of real life solar technologies. The statistical analysis reproduces the experimental findings, and represents a general tool for predicting the optimal compromise between dimensions and concentration of nMOFs with a given crystalline structure that minimizes the irradiance at which the system starts to fully operate.

Excision of Oral Leukoplakias by CO2 Laser on an Out-Patient Basis: A Useful Procedure for Prevention and Early Detection of Oral Carcinomas

Several epidemiologic studies have shown that oral cancer develops among individuals with a prior diagnosis of an oral premalignant lesion. Canceration chance in these patients is 17 %, with the greatest rate occuring in the second year of observation. Based on this data, since 1981, 92 leucoplakias have been treated by out-patient laser surgery at the Istituto Nazionale Tumori of Milano. The therapeutic technique was laser excision to obtain a specimen for histology. Two groups were distinguished according to the diagnostic procedure. Thirtythree lesions (December 1981 to December 1982) were operated on without preliminary histologic examination, on the basis of a simple clinical diagnosis. Since January 1983 all leukoplakias have been biopsied in a systematic way and those negative for cancer treated with laser. Histology of the specimen showed 5 squamous cell carcinomas (15 %) in the group of patients who did not undergo preoperative biopsy. Postoperative histology showed malignancy in 6 of 59 (10.2 %) cases in spite of negative preoperative biopsies. Speckled and erosive leukoplakias had the highest canceration rate. Three of 11 patients with cancer were treated by knife excision or interstitial needle implantation because of margins in tumoral tissue or because they were unvaluable for injury by heat. Results have been satisfactory, only 2 of 54 followed leukoplakias and none of the cancers recurred during a 2 year follow-up.

Lorlatinib Treatment Elicits Multiple On- and Off-Target Mechanisms of Resistance in ALK-Driven Cancer

: Targeted therapy changed the standard of care in ALK-dependent tumors. However, resistance remains a major challenge. Lorlatinib is a third-generation ALK inhibitor that inhibits most ALK mutants resistant to current ALK inhibitors. In this study, we utilize lorlatinib-resistant anaplastic large cell lymphoma (ALCL), non-small cell lung cancer (NSCLC), and neuroblastoma cell lines in vitro and in vivo to investigate the acquisition of resistance and its underlying mechanisms. ALCL cells acquired compound ALK mutations G1202R/G1269A and C1156F/L1198F in vitro at high drug concentrations. ALCL xenografts selected in vivo showed recurrent N1178H (5/10 mice) and G1269A (4/10 mice) mutations. Interestingly, intracellular localization of NPM/ALKN^1178H skewed toward the cytoplasm in human cells, possibly mimicking overexpression. RNA sequencing of resistant cells showed significant alteration of PI3K/AKT and RAS/MAPK pathways. Functional validation by small-molecule inhibitors confirmed the involvement of these pathways in resistance to lorlatinib. NSCLC cells exposed in vitro to lorlatinib acquired hyperactivation of EGFR, which was blocked by erlotinib to restore sensitivity to lorlatinib. In neuroblastoma, whole-exome sequencing and proteomic profiling of lorlatinib-resistant cells revealed a truncating NF1 mutation and hyperactivation of EGFR and ErbB4. These data provide an extensive characterization of resistance mechanisms that may arise in different ALK-positive cancers following lorlatinib treatment. SIGNIFICANCE: High-throughput genomic, transcriptomic, and proteomic profiling reveals various mechanisms by which multiple tumor types acquire resistance to the third-generation ALK inhibitor lorlatinib.

Abstract 3385: ETNK1 mutations promote ROS production and DNA damage through increased mitochondrial activity

Atypical chronic myeloid leukemia (aCML) is a clonal disorder belonging to the myelodysplastic/myeloproliferative syndromes. About 13% of aCML cases carry somatic mutations in ETNK1 gene, encoding for H243Y, N244S, and G245V substitutions. We previously showed that ETNK1 mutations cause a decreased catalytic activity of the enzyme. Despite this evidence however, their oncogenic role remained largely unexplained. Since ETNK1 activity is essential for the synthesis of phosphatidylethanolamine (PE) and given that PE is one of the most abundant phospholipids in the inner membrane of mitochondria, we focused our attention on mitochondrial activity. In order to characterize the oncogenic effect of ETNK1 variants we generated CRISPR/Cas9 clones carrying heterozygous N244S mutation and homozygous ETNK1 deletion (KO cells) on the 293 Flp-In™ cell-line. Both N244S and KO cells showed a significant increase in mitochondrial activity (1.78 and 2.13 fold increase, respectively; p= 0.0096 and p=0.0050) compared to WT, as assessed by MitoTracker™ Red. In line with this finding, electron microscopy revealed a significant modification in mitochondria morphology for N244S and KO cells, changing from an elongated, tubular shape to a round, swollen one. ATP (1.67 and 1.68 fold; p&lt;0.0001; ATPlite Luminescence Assay System) and ROS production (1.66 and 1.74 fold increase; p&lt;0.0001; CellROX™ Green Reagent) were similarly increased. Histone H2AX phosphorylation (γ-H2AX) analysis revealed a higher number of foci in N244S and KO cells (2.60±0.22 and 2.89±0.27; p&lt;0.0001) compared to WT (0.56±0.08). A similar increase in γ-H2AX (3.6 fold; p=0.0037) was present in primary samples from aCML patients carrying ETNK1 mutation compared to ETNK1-WT ones.

In line with these data, a higher mutation rate was detected in N244S and KO cells (8.09*10-7±9.6*10-8 and 8.20*10-7±1.28*10-7; p=0.0060 and p=0.0264) compared to WT (2.98*10-7±8.2*10-8) by 6-thioguanine assay.

The reconstruction of the hierarchy of somatic mutations in ETNK1-mutated aCML patients revealed that ETNK1 variants invariably occur very early in the evolution history of the aCML patients.

Taken together, our results show that impairment of ETNK1 function causes an increase in mitochondrial activity, which in turn leads to increased ROS production driving the accumulation of DNA mutations. Since the characterization of aCML subclonal architecture indicates ETNK1 mutations as a very early event in the history of the disease, we hypothesize that ETNK1 could contribute to the onset of aCML through the activation of a mutant phenotype, which in turn would accelerate the accumulation of further oncogenic mutations.

Citation Format: Diletta Fontana, Mario Mauri, Antonio Niro, Luca Massimino, Mayla Bertagna, Giovanni Zambrotta, Mario Bossi, Stefania Citterio, Barbara Crescenzi, Giovanni Signore, Vincenzo Piazza, Cristina Mecucci, Guido Cavaletti, Delphine Rea, Carlo Gambacorti-Passerini, Rocco Piazza. ETNK1 mutations promote ROS production and DNA damage through increased mitochondrial activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3385.

SETBP1 induces transcription of a network of development genes by acting as an epigenetic hub

SETBP1 variants occur as somatic mutations in several hematological malignancies such as atypical chronic myeloid leukemia and as de novo germline mutations in the Schinzel–Giedion syndrome. Here we show that SETBP1 binds to gDNA in AT-rich promoter regions, causing activation of gene expression through recruitment of a HCF1/KMT2A/PHF8 epigenetic complex. Deletion of two AT-hooks abrogates the binding of SETBP1 to gDNA and impairs target gene upregulation. Genes controlled by SETBP1 such as MECOM are significantly upregulated in leukemias containing SETBP1 mutations. Gene ontology analysis of deregulated SETBP1 target genes indicates that they are also key controllers of visceral organ development and brain morphogenesis. In line with these findings, in utero brain electroporation of mutated SETBP1 causes impairment of mouse neurogenesis with a profound delay in neuronal migration. In summary, this work unveils a SETBP1 function that directly affects gene transcription and clarifies the mechanism operating in myeloid malignancies and in the Schinzel–Giedion syndrome caused by SETBP1 mutations.

SETBP1 variants occur as somatic mutations in several malignancies and as de novo germline mutations in developmental disorders. Here the authors provide evidence that SETBP1 binds to gDNA in AT-rich promoter regions to promote target gene upregulation, indicating SETBP1 functions directly to regulate transcription.

Treatment of Advanced Breast Cancer with Norethisterone Acetate

The medical records of 84 postmenopausal women treated with oral norethisterone acetate (NTA) for advanced breast cancer were retrospectively analyzed. Treatment was devoid of significant toxicity. Twenty-one patients were not evaluable for treatment response either because of insufficient data or inadequate treatment trial. Complete plus partial response was obtained in 21 (33.3 %) of the 63 evaluable patients, with a median duration of 10 months. Disease stabilization was observed in 16 (25.4 %) patients for a median duration of 5 months, while 26 patients (41.3 %) showed progressive disease while on treatment. The best response was observed in women with dominant soft part disease and an age over 70 (CR+PR 48 %). The literature on norethisterone acetate is reviewed and compared with present results. The role of progestational agents in the treatment of advanced mammary carcinoma is discussed.

The Cost of Hospital Stay for Operable Breast Cancer

The cost of the first hospital stay for operable breast cancer was deducted by analysing a random sample of 100 admissions to the National Institute of Cancer during the period January-December 1989. The aims of the study were: (1) to describe and calculate the cost component of the stay; (2) to analyse whether any procedure, service rended or stage of the pathology might explain differences in the total costs of the stay; and (3) to acquire a better knowledge of the organizational aspects to be improved. With an average length of stay of 14.1 days, the overall total cost observed was 4.9 million lira (US $ 3.800, 1989 US dollars). A significant correlation between total cost and duration of stay was found (R2 = 0.982), while no or very little correlation was found between cost and the anatomical extent of disease (TNM stage) and different cost items (laboratory, imaging tests, operating room, etc.). Two homogeneous groups of cases were found: patients with quadrantectomy and patients with mastectomy. The cost of the latter was 40% greater than that of the former (P < 0.001) with a length of stay 52% longer (p < 0.001). This study does not concern the costs immediately following the stay, which namely are higher for the quadrantectomy because the radiotherapy outpatient procedures. Attention should be paid to reducing the length of stay, keeping waiting time for organizational procedures to a minimum during the stay.

Prognostic Significance of the Growth Rate of Breast Cancer: Preliminary Evaluation on the Follow-Up of 196 Breast Cancers

The doubling time (DT) of 196 consecutive breast cancers was studied by means of a double mammographic examination (average time between the 2 mammographies, 30 days) and calculated with the formula of exponential growth. On the basis of DT values the case series was divided into 3 groups of growth: fast (DT from 1 to 30 days), 31 cases (15.8 %), intermediate (DT from 31 to 90 days), 84 cases (42.9 %), slow (DT more than 90 days), 81 cases (41.3 %). No relationship was found between growth rate and size of tumor, or menopausal status of the patient. After mastectomy fast and slow cases were equally distributed in the N− and N+ groups, whereas for the intermediate cases the N−: N+ ratio was 1: 2. One hundred and thirty-four cases were followed for a period of 12 to 52 months. Evaluation was done on the basis of the subdivision into N− and N+, and the latter group into N+ (1–3) and N+ (> 3). For N− tumors the course of the disease was apparently not affected by the growth rate. However, the case of fast growing tumors showed a higher proportion of recurrences with respect to N+ slow growing tumors. This difference was even more noticeable the higher the number of involved lymph nodes, but not statistically significant. The course of slow growing tumors was identical in the N− and N+ groups, but all the N+ tumors were subjected to adjuvant chemotherapy.

Effect of Rubber Polarity on Cluster Formation in Rubbers Cross-Linked with Diels-Alder Chemistry

Diels–Alder chemistry has been used for the thermoreversible cross-linking of furan-functionalized ethylene/propylene (EPM) and ethylene/vinyl acetate (EVM) rubbers. Both furan-functionalized elastomers were successfully cross-linked with bismaleimide to yield products with a similar cross-link density. NMR relaxometry and SAXS measurements both show that the apolar EPM-g-furan precursor contains phase-separated polar clusters and that cross-linking with polar bismaleimide occurs in these clusters. The heterogeneously cross-linked network of EPM-g-furan contrasts with the homogeneous network in the polar EVM-g-furan. The heterogeneous character of the cross-links in EPM-g-furan results in a relatively high Young’s modulus, whereas the more uniform cross-linking in EVM-g-furan results in a higher tensile strength and elongation at break.

Impaired thromboxane receptor dimerization reduces signaling efficiency: A potential mechanism for reduced platelet function in vivo

Thromboxane A₂ is a potent mediator of inflammation and platelet aggregation exerting its effects through the activation of a G protein-coupled receptor (GPCR), termed TP. Although the existence of dimers/oligomers in Class A GPCRs is widely accepted, their functional significance still remains controversial. Recently, we have shown that TPα and TPβ homo-/hetero-dimers interact through an interface of residues in transmembrane domain 1 (TM1) whose disruption impairs dimer formation. Here, biochemical and pharmacological characterization of this dimer deficient mutant (DDM) in living cells indicates a significant impairment in its response to agonists. Interestingly, two single loss-of-function TPα variants, namely W29C and N42S recently identified in two heterozygous patients affected by bleeding disorders, match some of the residues mutated in our DDM. These two naturally occurring variants display a reduced potency to TP agonists and are characterized by impaired dimer formation in transfected HEK-293T cells. These findings provide proofs that lack of homo-dimer formation is a crucial process for reduced TPα function in vivo, and might represent one molecular mechanism through which platelet TPα receptor dysfunction affects the patient(s) carrying these mutations.