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Purpose To compare the characteristics, management, and prognosis of patients admitted to intensive care units (ICU) for coronavirus disease (COVID)-19 during the first two waves of the outbreak and to evaluate the relationship between ICU strain (ICU demand due to COVID-19 admissions) and mortality. Methods In a multicentre retrospective study, 1166 COVID-19 patients admitted to five ICUs in France between 20 February and 31 December 2020 were included. Data were collected at each ICU from medical records. A Cox proportional-hazards model identified factors associated with 28-day mortality. Results 640 patients (55%) were admitted during the first wave (February to June 2020) and 526 (45%) during the second wave (July to December 2020). ICU strain was lower during the second wave (-0.81 [-1.04 –-0.31] vs. 1.18 [-0.34–1.29] SD when compared to mean COVID-19 admission in each center during study period, P Conclusion The characteristics and the management of patients varied between the first and the second wave of the pandemic. Rather than the wave, ICU strain was independently associated with 28-day mortality, but not with hospital mortality.

BackgroundPregnant and postpartum women face unique challenges during the COVID-19 pandemic that may put them at elevated risk of mental health problems. However, few large-scale and no cross-national studies have been conducted to date that investigate modifiable pandemic-related behavioral or cognitive factors that may influence mental health in this vulnerable group. This international study sought to identify and measure the associations between pandemic-related information seeking, worries, and prevention behaviors on perinatal mental health during the COVID-19 pandemic.Methods and FindingsAn anonymous, online, cross-sectional survey of pregnant and postpartum women was conducted in 64 countries between May 26 2020 and June 13 2020. The survey, available in twelve languages, was hosted on the Pregistry platform for COVID-19 studies (https://corona.pregistry.com), and advertised predominantly in social media channels and online parenting forums. Participants completed measures on demographic characteristics, COVID-19 exposure and worries, media exposure, COVID-19 prevention behaviors, and mental health symptoms including posttraumatic stress symptoms via the IES-6, anxiety/depression via the PHQ-4, and loneliness via the UCLA-3. Of the 6,894 participants, substantial proportions of women scored at or above the cut-offs for elevated posttraumatic stress (2,979 [43%]), anxiety/depression (2,138 [31%], and loneliness (3,691 [53%]). Information seeking from any source (e.g., social media, news, talking to others) five or more times per day was associated with more than twice the odds of elevated posttraumatic stress and anxiety/depression, in adjusted models. A large majority of women (86%) reported being somewhat or very worried about COVID-19. The most commonly reported worries were related to pregnancy and delivery, including family being unable to visit after delivery (59%), the baby contracting COVID-19 (59%), lack of a support person during delivery (55%), and COVID-19 causing changes to the delivery plan (41%). Greater worries related to children (i.e. inadequate childcare, their infection risk) and missing medical appointments were associated with significantly higher odds of posttraumatic stress, anxiety/depression and loneliness. Engaging in hygiene-related COVID-19 prevention behaviors (face mask-wearing, washing hands, disinfecting surfaces) were not related to mental health symptoms or loneliness.ConclusionsClinically significant posttraumatic stress, anxiety/depression, and loneliness are highly prevalent in pregnant and postpartum women across 64 countries during the COVID-19 pandemic. Excessive information seeking and worries related to children and medical care are associated with clinically significant symptoms, whereas engaging in hygiene-related preventive measures were not. In addition to screening and monitoring mental health symptoms, reinforcing healthy information seeking, addressing worries about access to medical care and the well-being of their children, and strategies to target loneliness (e.g., online support groups) should be part of intervention efforts for perinatal women. Public and mental health interventions need to explicitly address the impact of COVID-19 on both physical and mental health in perinatal women, as prevention of viral exposure itself does not mitigate the mental health impact of the pandemic.

Site-specific conjugation of ubiquitin onto a range of DNA repair proteins regulates their critical functions in the DNA damage response. Biochemical and structural characterization of these functions are limited by an absence of tools for the purification of DNA repair proteins in purely the ubiquitinated form. To overcome this barrier, we designed a ubiquitin fusion protein that is N-terminally biotinylated and can be conjugated by E3 RING ligases onto various substrates. Biotin affinity purification of modified proteins, followed by cleavage of the affinity tag leads to release of natively-mono-ubiquitinated substrates. As proof-of-principle, we applied this method to several substrates of mono-ubiquitination in the Fanconi anemia (FA)-BRCA pathway of DNA interstrand crosslink repair. These include the FANCI:FANCD2 complex, the PCNA trimer and BRCA1 modified nucleosomes. This method provides a simple approach to study the role of mono-ubiquitination in DNA repair or any other mono-ubiquitination signaling pathways.

International audience; Background: Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia (ARVC/D) is an inherited cardiomyopathy mainly caused by heterozygous desmosomal gene mutations, the major gene being PKP2. The genetic cause remains unknown in ~50% of probands with routine desmosomal gene screening. The aim of this study was to assess the diagnostic accuracy of whole exome sequencing (WES) in ARVC/D with negative genetic testing.Methods: WES was performed in 22 patients, all without a mutation identified in desmosomal genes. Putative pathogenic variants were screened in 96 candidate genes associated with other cardiomyopathies/channelopathies. The sequencing coverage depth of PKP2, DSP, DSG2, DSC2, JUP and TMEM43 exons was compared to the mean coverage distribution to detect large insertions/deletions. All suspected deletions were verified by real-time qPCR, Multiplex-Ligation-dependent-Probe-Amplification (MLPA) and cGH-Array. MLPA was performed in 50 additional gene-negative probands.Results: Coverage-depth analysis from the 22 WES data identified two large heterozygous PKP2 deletions: one from exon 1 to 14 and one restricted to exon 4, confirmed by qPCR and MLPA. MLPA identified 2 additional PKP2 deletions (exon 1–7 and exon 1–14) in 50 additional probands confirming a significant frequency of large PKP2 deletions (5.7%) in gene-negative ARVC/D. Putative pathogenic heterozygous variants in EYA4, RBM20, PSEN1, and COX15 were identified in 4 unrelated probands.Conclusion: A rather high frequency (5.7%) of large PKP2 deletions, undetectable by Sanger sequencing, was detected as the cause of ARVC/D. Coverage-depth analysis through next-generation sequencing appears accurate to detect large deletions at the same time than conventional putative mutations in desmosomal and cardiomyopathy-associated genes.

[This corrects the article DOI: 10.1371/journal.pone.0137339.].

Inhibiting the synthesis of endogenous prostaglandins with nonsteroidal anti-inflammatory drugs exacerbates arterial hypertension. We hypothesized that the converse, i.e., raising the level of endogenous prostaglandins, might have anti-hypertensive effects. To accomplish this, we focused on inhibiting the prostaglandin transporter PGT (SLCO2A1), which is the obligatory first step in the inactivation of several common PGs. We first examined the role of PGT in controlling arterial blood pressure blood pressure using anesthetized rats. The high-affinity PGT inhibitor T26A sensitized the ability of exogenous PGE2 to lower blood pressure, confirming both inhibition of PGT by T26A and the vasodepressor action of PGE2 T26A administered alone to anesthetized rats dose-dependently lowered blood pressure, and did so to a greater degree in spontaneously hypertensive rats than in Wistar-Kyoto control rats. In mice, T26A added chronically to the drinking water increased the urinary excretion and plasma concentration of PGE2 over several days, confirming that T26A is orally active in antagonizing PGT. T26A given orally to hypertensive mice normalized blood pressure. T26A increased urinary sodium excretion in mice and, when added to the medium bathing isolated mouse aortas, T26A increased the net release of PGE2 induced by arachidonic acid, inhibited serotonin-induced vasoconstriction, and potentiated vasodilation induced by exogenous PGE2. We conclude that pharmacologically inhibiting PGT-mediated prostaglandin metabolism lowers blood pressure, probably by prostaglandin-induced natriuresis and vasodilation. PGT is a novel therapeutic target for treating hypertension.

Introduction In autism spectrum disorders (ASD), complex gene-environment interactions contribute to disease onset and progress. Given that gastro-intestinal dysfunctions are common in ASD, we postulated involvement of microbial dysbiosis in ASD and investigated, under a case-control design, the influence of DNA polymorphisms in the CLEC7A gene that encodes a pivotal fungal sensor, Dectin-1. Material and methods DNAs from 478 ASD patients and 351 healthy controls (HC) were analyzed for the CLEC7A rs16910631G/A and rs2078178 A/G single nucleotide polymorphisms (SNPs). Differences in the distribution of allele, genotype and haplotype by Chi-square testing and nonparametric analysis by Kruskal-Wallis/Mann–Whitney tests, where appropriate, were performed. The free statistical package R.2.13 software was used for the statistical analysis. Results We found that the CLEC7A rs2078178 G allele and GG genotype were more prevalent in HC as compared to ASD but failed to reach statistical significance for the latter (pc = 0.01, 0.06 respectively). However, after phenotype-based stratification, the CLEC7A rs2078178 G allele and GG genotype were found to be significantly more frequent in the Asperger group as compared to other ASD subsets (pc = 0.02, 0.01), a finding reinforced by haplotype analysis (rs2078178/rs16910631 G-G/G-G) (pc = 0.002). Further, intellectual quotient (IQ)-based stratification of ASD patients revealed that IQ values increase linearly along the CLEC7A rs2078178 AA, AG and GG genotypes (p = 0.05) and in a recessive manner (GG vs. AA+AG p = 0.02), further confirmed by haplotype distribution (CLEC7A rs2078178-16910631; A-G/A-G, A-G/G-G and G-G/G-G, p = 0.02, G-G/G-G vs. others, p = 0.01). Conclusion Our data suggest that the genetic diversity of CLEC7A gene influences the ASD phenotype by behaving as a disease specifier and imply that the genetic control of innate immune response could determine the ASD phenotype.

Plant growth-promoting bacteria (PGB) induce positive effects in plants, for instance, increased growth and reduced abiotic stresses susceptibility. The mechanisms by which these bacteria impact the host plant are numerous, diverse and often specific. Here, we studied the agronomical, molecular and biochemical effects of the endophytic PGB Bacillus subtilis B26 on the full life cycle of Brachypodium distachyon Bd21, an established model species for functional genomics in cereal crops and temperate grasses. Inoculation of Brachypodium with B. subtilis strain B26 increased root and shoot weights, accelerated growth rate and seed yield as compared to control plants. B. subtilis strain B26 efficiently colonized the plant and was recovered from roots, stems and blades as well as seeds of Brachypodium, indicating that the bacterium is able to migrate, spread systemically inside the plant, establish itself in the aerial plant tissues and organs, and is vertically transmitted to seeds. The presence of B. subtilis strain B26 in the seed led to systemic colonization of the next generation of Brachypodium plants. Inoculated Brachypodium seedlings and mature plants exposed to acute and chronic drought stress minimized the phenotypic effect of drought compared to plants not harbouring the bacterium. Protection from the inhibitory effects of drought by the bacterium was linked to upregulation of the drought-response genes, DREB2B-like, DHN3-like and LEA-14-A-like and modulation of the DNA methylation genes, MET1B-like, CMT3-like and DRM2-like, that regulate the process. Additionally, total soluble sugars and starch contents increased in stressed inoculated plants, a biochemical indication of drought tolerance. In conclusion, we show a single inoculation of Brachypodium with a PGB affected the whole growth cycle of the plant, accelerating its growth rates, shortening its vegetative period, and alleviating drought stress effects. These effects are relevant to grasses and cereal crops.

Gene-environment interactions may play an important role in modulating the impact of early-life stressful events on the clinical course of bipolar disorder (BD), particularly associated to early age at onset. Immune dysfunction is thought to be an important mechanism linking childhood trauma with early-onset BD, thus the genetic diversity of immune-related loci may account for an important part of the interindividual susceptibility to this severe subform. Here we investigated the potential interaction between genetic variants of Toll-like receptors 2 (TLR2) and 4 (TLR4), major innate immune response molecules to pathogens, and the childhood trauma questionnaire (CTQ) in age at onset of BD. We recruited 531 BD patients (type I and II or not otherwise specified), genotyped for the TLR2 rs4696480 and rs3804099 and TLR4 rs1927914 and rs11536891 single-nucleotide polymorphisms and recorded for history of childhood trauma using the CTQ. TLR2 and TLR4 risk genotype carrier state and history of childhood emotional, physical and sexual abuses were evaluated in relation to age at onset as defined by the age at first manic or depressive episode. We observed a combined effect of TLR2 rs3804099 TT genotype and reported sexual abuse on determining an earlier age at onset of BD by means of a Kaplan-Meier survival curve (p = 0.002; corrected p = 0.02). Regression analysis, however, was non-significant for the TLR2-CTQ sexual abuse interaction term. The negative effects of childhood sexual abuse on age at onset of BD may be amplified in TLR2 rs3804099 risk genotype carriers through immune-mediated pathways. Clinical characteristics of illness severity, immune phenotypes and history of early life infectious insults should be included in future studies involving large patient cohorts.

Objective Focal cortical dysplasias (FCDs) are mainly located in the frontal region, with a particular tropism for the central sulcus. Up to 30% of lesions are undetected (magnetic resonance [MR]-negative FCD patients) or belatedly diagnosed by visual analysis of MR images. We propose an automated sulcus-based method to analyze abnormal sulcal patterns associated with central FCD, taking into account the normal interindividual sulcal variability. Methods We retrospectively studied 29 right-handed patients with FCD in the central region (including 12 MR negative histologically-confirmed cases) and 29 right-handed controls. The analysis of sulcal abnormalities from T1-weighted MR imaging (MRI) was performed using a graph-based representation of the cortical folds and an automated sulci recognition system, providing a new quantitative criterion to describe sulcal patterns, termed sulcus energy. Results Group analysis showed that the central sulcus in the hemisphere ipsilateral to the FCD exhibited an abnormal sulcal pattern compared with controls (p = 0.032). FCDs were associated with abnormal patterns of the central sulci compared with controls (p = 0.006), a result that remained significant when MR-negative and MR-positive patients were considered separately, while the effects of sex, age and MR-field were not significant. At the individual level, sulcus energy alone failed to detect the FCD lesion. We found, however, a significant association between maximum z-scores and the site of FCD (p = 0.0046) which remained significant in MR-negative (p = 0.024) but not in MR-positive patients (p = 0.058). The maximum z-score pointed to an FCD sulcus in four MR-negative and five MR-positive patients. Conclusions We identified abnormal sulcal patterns in patients with FCD of the central region compared with healthy controls. The abnormal sulcal patterns ipsilateral to the FCD and the link between sulcus energy and the FCD location strengthen the interest of sulcal abnormalities in FCD patients.

Epilepsy is a chronic brain disorder involving recurring seizures often precipitated by an earlier neuronal insult. The mechanisms that link the transient neuronal insult to the lasting state of epilepsy are unknown. Here we tested the possible role of DNA methylation in mediating long-term induction of epileptiform activity by transient kainic acid exposure using in vitro and in vivo rodent models. We analyzed changes in the gria2 gene, which encodes for the GluA2 subunit of the ionotropic glutamate, alpha-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid receptor and is well documented to play a role in epilepsy. We show that kainic acid exposure for two hours to mouse hippocampal slices triggers methylation of a 5' regulatory region of the gria2 gene. Increase in methylation persists one week after removal of the drug, with concurrent suppression of gria2 mRNA expression levels. The degree of kainic acid-induced hypermethylation of gria2 5' region varies between individual slices and correlates with the changes in excitability induced by kainic acid. In a rat in vivo model of post kainic acid-induced epilepsy, we show similar hypermethylation of the 5' region of gria2. Inter-individual variations in gria2 methylation, correlate with the frequency and intensity of seizures among epileptic rats. Luciferase reporter assays support a regulatory role for methylation of gria2 5' region. Inhibition of DNA methylation by RG108 blocked kainic acid-induced hypermethylation of gria2 5' region in hippocampal slice cultures and bursting activity. Our results suggest that DNA methylation of such genes as gria2 mediates persistent epileptiform activity and inter-individual differences in the epileptic response to neuronal insult and that pharmacological agents that block DNA methylation inhibit epileptiform activity raising the prospect of DNA methylation inhibitors in epilepsy therapeutics.

The metabolic adaptations to fasting in the liver are largely controlled by the nuclear hormone receptor peroxisome proliferator-activated receptor alpha (PPARα), where PPARα upregulates genes encoding the biochemical pathway for β-oxidation of fatty acids and ketogenesis. As part of an effort to identify and characterize nutritionally regulated genes that play physiological roles in the adaptation to fasting, we identified Major facilitator superfamily domain-containing protein 2a (Mfsd2a) as a fasting-induced gene regulated by both PPARα and glucagon signaling in the liver. MFSD2A is a cell-surface protein homologous to bacterial sodium-melibiose transporters. Hepatic expression and turnover of MFSD2A is acutely regulated by fasting/refeeding, but expression in the brain is constitutive. Relative to wildtype mice, gene-targeted Mfsd2a knockout mice are smaller, leaner, and have decreased serum, liver and brown adipose triglycerides. Mfsd2a knockout mice have normal liver lipid metabolism but increased whole body energy expenditure, likely due to increased β-oxidation in brown adipose tissue and significantly increased voluntary movement, but surprisingly exhibited a form of ataxia. Together, these results indicate that MFSD2A is a nutritionally regulated gene that plays myriad roles in body growth and development, motor function, and lipid metabolism. Moreover, these data suggest that the ligand(s) that are transported by MFSD2A play important roles in these physiological processes and await future identification.

Expression of the hominoid-specific TBC1D3 oncoprotein enhances growth factor receptor signaling and subsequently promotes cellular proliferation and survival. Here we report that TBC1D3 is degraded in response to growth factor signaling, suggesting that TBC1D3 expression is regulated by a growth factor-driven negative feedback loop. To gain a better understanding of how TBC1D3 is regulated, we studied the effects of growth factor receptor signaling on TBC1D3 post-translational processing and turnover. Using a yeast two-hybrid screen, we identified CUL7, the scaffolding subunit of the CUL7 E3 ligase complex, as a TBC1D3-interacting protein. We show that CUL7 E3 ligase ubiquitinates TBC1D3 in response to serum stimulation. Moreover, TBC1D3 recruits F-box 8 (Fbw8), the substrate recognition domain of CUL7 E3 ligase, in pull-down experiments and in an in vitro assay. Importantly, alkaline phosphatase treatment of TBC1D3 suppresses its ability to recruit Fbw8, indicating that TBC1D3 phosphorylation is critical for its ubiquitination and degradation. We conclude that serum- and growth factor-stimulated TBC1D3 ubiquitination and degradation are regulated by its interaction with CUL7-Fbw8.

BackgroundTo investigate the association between severity of acute kidney injury (AKI) and outcome, systemic inflammatory phenotype and HLA genotype in severe sepsis.Methodology/principal findingsProspective multicenter observational study done in 4 intensive care units in two university hospitals. Severe sepsis and septic shock patients with at least 2 organ failures based on the SOFA score were classified: 1) "no AKI", 2) "mild AKI" (grouping stage 1 and 2 of AKIN score) and 3) "severe AKI" (stage 3 of AKIN score). Sequential measurements: The vasopressor dependency index (VDI; dose and types of drugs) to evaluate the association between hemodynamic status and the development of early AKI; plasma levels of IL-10, macrophage migration inhibitory factor (MIF), IL-6 and HLA-DR monocyte expression. Genotyping of the 13 HLA-DRB1 alleles with deduction of presence of HLA-DRB3, -DRB4 and -DRB5 genes. We used multivariate analysis with competitive risk model to study associations. Overall, 176 study patients (146 with septic shock) were classified from AKIN score as "no AKI" (n = 43), "mild AKI" (n = 74) or "severe AKI" (n = 59). The VDI did not differ between groups of AKI. After adjustment, "mild and severe AKI" were an independent risk factor for mortality (HR 2.42 95%CI[1.01-5.83], p = 0.048 and HR 1.99 95%CI[1.30-3.03], p = 0.001 respectively). "Severe AKI" had higher levels of plasma IL-10, MIF and IL-6 compared to "no AKI" and mild AKI (pConclusionsAKI severity is independently associated with mortality and plasma IL-10, MIF or IL-6 levels. Presence of 4 alleles of HLA-DRB in severe AKI patients seems associated with a lower need of RRT.

Mycoplasma pneumoniae infections occur both endemically and epidemically, and macrolide resistance has been spreading for 10 years worldwide. A substantial increased incidence of M. pneumoniae infections has been reported in several countries since 2010. Whether this increased incidence is attributed to different or to the same M. pneumoniae genotype is unknown. We have developed a multilocus variable-number tandem-repeat ( VNTR) analysis ( MLVA) for the molecular typing of M. pneumoniae isolates. In this study, the MLVA typing method was modified and validated to be applicable directly to respiratory tract specimens without culture. This method was applied to 34 M. pneumoniae-positive specimens received at the Bordeaux Hospital, France, between 2007 and 2010 in an endemic setting, and to 63 M. pneumoniae-positive specimens collected during an epidemic surge of M. pneumoniae infections in 2010 in Jerusalem, Israel. The M. pneumoniae endemic spread was shown to be polyclonal in France, with 15 MLVA types identified. Strikingly, the Israeli epidemic surge was also a multi-clonal phenomenon, with 18 circulating MLVA types. The macrolide resistance-associated substitution, A2058G, was found in 22% of the Israeli patients. Macrolide-resistant M. pneumoniae belonged to four MLVA types, the MLVA type Z being the most frequent one. An association between the MLVA type Z and macrolide resistance might exist since macrolide resistance was present or generated during the course of illness in all patients infected with this MLVA type. In conclusion, the discriminatory power of the MLVA showed that the spread of M. pneumoniae strains in France in an endemic setting was polyclonal as well as the surge of M. pneumoniae infections in Israel in 2010.

Background Sepsis is a multifactorial pathology with high susceptibility to secondary infections. Innate and adaptive immunity are affected in sepsis, including monocyte deactivation. Methodology/Principal Findings To better understand the effects of alterations in monocytes on the regulation of immune responses during sepsis, we analyzed their differentiation in dendritic cell (DC). Cells from septic patients differentiated overwhelmingly into CD1a−negative DC, a population that was only a minor subset in controls and that is so far poorly characterized. Analysis of T cell responses induced with purified CD1a−negative and CD1a+ DC indicated that (i) CD1a−negative DC from both healthy individuals and septic patients fail to induce T cell proliferation, (ii) TGFβ and IL-4 were strongly produced in mixed leukocyte reaction (MLR) with control CD1a−negative DC; reduced levels were produced with patients DC together with a slight induction of IFNγ, (iii) compared to controls, CD1a+ DC derived from septic patients induced 3-fold more Foxp3+ T cells. Conclusion/Significance Our results indicate a strong shift in DC populations derived from septic patients’ monocytes with expanded cell subsets that induce either T cell anergy or proliferation of T cells with regulatory potential. Lower regulatory cytokines induction on a per cell basis by CD1a−negative dendritic cells from patients points however to a down regulation of immune suppressive abilities in these cells.

Background: Facioscapulohumeral muscular dystrophy (FSHD) is linked to deletions in 4q35 within the D4Z4 repeat array in which we identified the double homeobo x4( DUX4) gene. We found stable DUX4 mRNAs only derived from the most distal D4Z4 unit and unexpectedly extended to the flanking pLAM region that provided an intron and a polyadenylation signal. DUX4 encodes a transcription factor expressed in FSHD but not control primary myoblasts or muscle biopsies. The DUX4 protein initiates a large transcription deregulation cascade leading to muscle atrophy and oxidative stress, which are FSHD key features. Methodology/Principal Findings: We now show that transfection of myoblasts with a DUX4 expression vector leads to atrophic myotube formation associated with the induction of E3 ubiquitin ligases (MuRF1 and Atrogin1/MAFbx) typical of muscle atrophy. DUX4 induces expression of downstream targets deregulated in FSHD such as mu-crystallin and TP53. We developed specific siRNAs and antisense oligonucleotides (AOs) targeting the DUX4 mRNA. Addition of these antisense agents to primary FSHD myoblast cultures suppressed DUX4 protein expression and affected expression of the abovementioned markers. Conclusions/Significance: These results constitute a proof of concept for the development of therapeutic approaches for FSHD targeting DUX4 expression.

International audience; BACKGROUND: The aggressiveness of melanoma tumors is likely to rely on their well-recognized heterogeneity and plasticity. Melanoma comprises multi-subpopulations of cancer cells some of which may possess stem cell-like properties. Although useful, the sphere-formation assay to identify stem cell-like or tumor initiating cell subpopulations in melanoma has been challenged, and it is unclear if this model can predict a functional phenotype associated with aggressive tumor cells. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the molecular and functional phenotypes of melanoma spheroids formed in neural crest cell medium. Whether from metastatic or advanced primary tumors, spheroid cells expressed melanoma-associated markers. They displayed higher capacity to differentiate along mesenchymal lineages and enhanced expression of SOX2, NANOG, KLF4, and/or OCT4 transcription factors, but not enhanced self-renewal or tumorigenicity when compared to their adherent counterparts. Gene expression profiling attributed a neural crest cell signature to these spheroids and indicated that a migratory/invasive and immune-function modulating program could be associated with these cells. In vitro assays confirmed that spheroids display enhanced migratory/invasive capacities. In immune activation assays, spheroid cells elicited a poorer allogenic response from immune cells and inhibited mitogen-dependent T cells activation and proliferation more efficiently than their adherent counterparts. Our findings reveal a novel immune-modulator function of melanoma spheroids and suggest specific roles for spheroids in invasion and in evasion of antitumor immunity. CONCLUSION/SIGNIFICANCE: The association of a more plastic, invasive and evasive, thus a more aggressive tumor phenotype with melanoma spheroids reveals a previously unrecognized aspect of tumor cells expanded as spheroid cultures. While of limited efficiency for melanoma initiating cell identification, our melanoma spheroid model predicted aggressive phenotype and suggested that aggressiveness and heterogeneity of melanoma tumors can be supported by subpopulations other than cancer stem cells. Therefore, it could be constructive to investigate melanoma aggressiveness, relevant to patients and clinical transferability.