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SummaryGlucocorticoids are important for proper organ maturation1. Increased exposure to these hormones during pregnancy, as a result of commonly prescribed synthetic glucocorticoids such as dexamethasone in preterm births2, has been associated with lasting effects on the offspring, including on neurodevelopment and neuropsychiatric disease risk3. While the consequences of glucocorticoid excess in term and especially adult brain have been extensively studied, mainly in rodents4, studies on their effects during early human cortical development are absent. Here we use human cerebral organoids and mice to study cell-type specific effects of glucocorticoids on neurogenic processes. We show that glucocorticoid administration during neurogenesis alters the cellular architecture of the developing cortex by increasing a specific type of gyrencephalic species-enriched basal progenitors that co-express PAX6 and EOMES. This effect is mediated via the glucocorticoid-responsive transcription factor ZBTB16 as shown with overexpression, genetic knock-down and reporter assays experiments in organoids and embryonic mouse models and leads to increased production of deep-layer neurons. A phenome-wide mendelian randomization analysis of a genetic intronic enhancer variant that moderates glucocorticoid-induced ZBTB16 levels, as shown with enhancer assays and enhancer-editing in organoids, reveals potential causal relationships with increased educational attainment as well as neuroimaging phenotypes in adults. In this study we provide a cellular and molecular pathway for the effects of glucocorticoids on human neurogenesis that potentially explains postnatal phenotypes and may be used to refine treatment guidelines.

A number of prenatal experiences are associated with adverse outcomes after birth, ranging from cardiovascular problems to psychiatric disease. Prenatal stress is associated with neurodevelopmental alterations that persist after birth and manifest at the behavioral level, for example, increased fearfulness, and at the physiological one, that is, brain structural and functional changes. Understanding the mechanisms that drive these lasting effects may help in preventing long-term negative outcomes of prenatal stress. Elevated glucocorticoid signaling in utero may be one of the key mediators of prenatal stress effects on the offspring. In this review, we summarize how prenatal glucocorticoids may impact the activity of the fetal hypothalamic-pituitary-adrenal (HPA) axis, disrupt neurodevelopmental processes and alter the epigenetic landscape of the fetus. We also discuss the need to take into consideration the interaction of these processes with the offspring's genetic landscape.

Hypothalamic-pituitary adrenal (HPA)axis dysregulation has long been implicated in stress-related disorders such as major depression and post-traumatic stress disorder. Glucocorticoids (GCs) are released from the adrenal glands as a result of HPA-axis activation. The release of GCs is implicated with several neurobiological changes that are associated with negative consequences of chronic stress and the onset and course of psychiatric disorders. Investigating the underlying neurobiological effects of GCs may help to better understand the pathophysiology of stress-related psychiatric disorders. GCs impact a plethora of neuronal processes at the genetic, epigenetic, cellular, and molecular levels. Given the scarcity and difficulty in accessing human brain samples, 2D and 3D in vitro neuronal cultures are becoming increasingly useful in studying GC effects. In this review, we provide an overview of in vitro studies investigating the effects of GCs on key neuronal processes such as proliferation and survival of progenitor cells, neurogenesis, synaptic plasticity, neuronal activity, inflammation, genetic vulnerability, and epigenetic alterations. Finally, we discuss the challenges in the field and offer suggestions for improving the use of in vitro models to investigate GC effects.

OBJECTIVE: A fine-tuned balance of glucocorticoid receptor (GR) activation is essential for organ formation, with disturbances influencing many health outcomes. In utero, glucocorticoids have been linked to brain-related negative outcomes, with unclear underlying mechanisms, especially regarding cell-type-specific effects. An in vitro model of fetal human brain development, induced human pluripotent stem cell (hiPSC)-derived cerebral organoids, was used to test whether cerebral organoids are suitable for studying the impact of prenatal glucocorticoid exposure on the developing brain. METHODS: The GR was activated with the synthetic glucocorticoid dexamethasone, and the effects were mapped using single-cell transcriptomics across development. RESULTS: The GR was expressed in all cell types, with increasing expression levels through development. Not only did its activation elicit translocation to the nucleus and the expected effects on known GR-regulated pathways, but also neurons and progenitor cells showed targeted regulation of differentiation- and maturation-related transcripts. Uniquely in neurons, differentially expressed transcripts were significantly enriched for genes associated with behavior-related phenotypes and disorders. This human neuronal glucocorticoid response profile was validated across organoids from three independent hiPSC lines reprogrammed from different source tissues from both male and female donors. CONCLUSIONS: These findings suggest that excessive glucocorticoid exposure could interfere with neuronal maturation in utero, leading to increased disease susceptibility through neurodevelopmental processes at the interface of genetic susceptibility and environmental exposure. Cerebral organoids are a valuable translational resource for exploring the effects of glucocorticoids on early human brain development.

Objective: Oxidative stress plays an important role in the pathogenesis of diabetic retinopathy. The aim of the present study was to investigate the effect of Crocus sativus L. styles (saffron) extract on oxidative stress indices of retina in streptozotocin (STZ)-induced diabetic rats. Methods: Adult male Wistar rats (n=20) were randomized into the following 4 groups (n=6-7/ group): Control group (C): normal, Control + Saffron group (CS): non-diabetic rats treated with 60 mg/ kg of saffron extract, Diabetic group (D) and Diabetic + Saffron group (DS): diabetic rats treated with 60 mg/ kg saffron extract. We determined the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) as markers of antioxidant response, as well as malondialdehyde (MDA) as a marker of lipid peroxidation. Results: Induction of diabetes caused a significant decline in the activities of CAT (76.43%), SOD (53.43%) and GPx (77.58%). MDA levels were significantly lower in the DS group (0.878 ± 0.375 nmol MDA/ mg protein) as compared to D group (1.950 ± 0.299 nmol MDA/ mg protein, p 1.8-fold increase in the activity of CAT (p

Malignant pleural mesothelioma (MPM) arises from mesothelial cells lining the pleural cavity of asbestos-exposed individuals and rapidly leads to the development of pleural effusion and death. MPM harbours loss-of-function mutations in genes likeBAP1, NF2, CDKN2A, andTP53, but isolated deletion of these genes alone in mice does not cause MPM and mouse models of the disease are sparse. Here we show that a significant proportion of human MPM harbour point mutations and copy number alterations in theKRASproto-oncogene. These mutations are likely pathogenic, since ectopic expression of mutantKRASG12Din the pleural mesothelium of conditional mice causes MPM. Murine MPM cell lines derived from these tumours carry the initiatingKRASG12Dlesions, secondaryBap1alterations, and human MPM-like gene expression profiles. Moreover, they are transplantable and actionable by KRAS inhibition. Our results indicate thatKRASmutations likely play an important and underestimated role in MPM, which warrants further exploration.

The cellular architecture of the developing brain under physiological conditions has been widely studied over the years using rodent models ([Gotz and Huttner, 2005][1]), human fetal brains ([Polioudakis et al., 2019][2]), and, more recently, in vitro three-dimensional models of the primate and

ImportancePleural effusions frequently signal disseminated cancer. Diagnostic markers of pleural malignancy at presentation that would assess cancer risk and would streamline diagnostic decisions remain unidentified.ObjectiveThe present study aimed at identifying and validating predictors of malignant pleural effusion at patient presentation.DESIGN, SETTING, AND PARTICIPANTSA consecutive cohort of 323 patients with pleural effusion (PE) from different etiologies were recruited between 2013-2017 and was retrospectively analyzed. Data included history, chest X-ray, and blood/pleural fluid cell counts and biochemistry. Group comparison, receiver-operator characteristics, unsupervised hierarchical clustering, binary logistic regression, and random forests were used to develop the malignant pleural effusion detection (MAPED) score. MAPED was validated in an independent retrospective UK cohort (n= 238).Main Outcomes and MeasuresThe outcome was diagnostic of pleural effusion in patients, and the clinical and laboratory indicators available of the patient were measured.ResultsFive variables showed significant diagnostic power and were incorporated into the 5-point MAPED score. Age > 55 years, effusion size > 50% of the most affected lung field, pleural neutrophil count < 2,500/mm3, effusion protein > 3.5 g/dL, and effusion lactate dehydrogenase > 250 U/L, each scoring one point, predicted underlying cancer with the area under curve(AUC) = 0.819 (sensitivity=82%, specificity=74%,P< 10-15) in the derivation cohort. The AUC and net reclassification improvement (NRI) of MAPED score and cytology were not significantly different. However, the integrated discrimination improvement (IDI) of The MAPED score displayed a slight increment(PConclusionsThe MAPED score identifies malignant pleural effusions with satisfactory accuracy and can be used complementary to cytology to streamline diagnostic procedures.

Adolescence is an important period when the brain undergoes many changes. Because the brain is changing so much at this time, our experiences can have a huge impact on the brain’s health. Positive experiences keep the mind healthy, whereas negative experiences can lead to mental disorders. To process all the information that comes into the brain, the brain cells must talk with each other. They communicate via messenger systems. One of these systems is called the endocannabinoid (eCB) system. The eCB system plays an important role in the changes that happen in the adolescent brain. In this article, we see how the eCB system is affected by cannabis and how this may lead to a mental disorder.

A fine-tuned balance of glucocorticoid receptor (GR) activation is essential for organ formation, with disturbances influencing health outcomes. Excess GR-activation in utero has been linked to brain-related negative outcomes, with unclear underlying mechanisms, especially regarding cell-type specific effects. To address this, we used an in vitro model of fetal human brain, induced pluripotent-stem-cell-derived cerebral organoids, and mapped GR-activation effects using single-cell transcriptomics across development. Interestingly, neurons showed targeted regulation of differentiation- and maturation-related transcripts, suggesting a delay of these processes upon GR-activation. Uniquely in neurons, differentially-expressed transcripts were significantly enriched for genes associated with behavior-related phenotypes and disorders. This suggests that aberrant GR-activation could impact proper neuronal maturation, leading to increased disease susceptibility, through neurodevelopmental processes at the interface of genetic susceptibility and environmental exposure.

Malignant pleural effusion (MPE) is a frequent metastatic manifestation of human cancers. While we previously identified KRAS mutations as molecular culprits of MPE formation, the underlying mechanism remained unknown. Here, we determine that non-canonical IKKα-RelB pathway activation of KRAS-mutant tumor cells mediates MPE development and this is fueled by host-provided interleukin IL-1β. Indeed, IKKα is required for the MPE-competence of KRAS-mutant tumor cells by activating non-canonical NF-κB signaling. IL-1β fuels addiction of mutant KRAS to IKKα resulting in increased CXCL1 secretion that fosters MPE-associated inflammation. Importantly, IL-1β-mediated NF-κB induction in KRAS-mutant tumor cells, as well as their resulting MPE-competence, can only be blocked by co-inhibition of both KRAS and IKKα, a strategy that overcomes drug resistance to individual treatments. Hence we show that mutant KRAS facilitates IKKα-mediated responsiveness of tumor cells to host IL-1β, thereby establishing a host-to-tumor signaling circuit that culminates in inflammatory MPE development and drug resistance., Malignant pleural effusion (MPE) is a life-threatening cancer-related disorder. Here, the authors show that KRAS-mutant tumor cells require IKKα, activated via host-provided IL-1β, to promote MPE development and that co-inhibition of both KRAS and IKKα ameliorates the development of MPE in mouse models.

Background: Malignant pleural mesothelioma (MPM) is a highly aggressive tumor linked to loss of tumor suppressorsBAP1, NF2, andTRP53and accompanied by malignant pleural effusion (MPE). Aim: To develop novel mouse models of MPM with MPE. Methods: Intercrosses of conditional mutantKRAS (LoxP-STOP-LoxP.KRASG12D; K) andTRP53-deleted (LoxP.Trp53.LoxP; P) mice received intrapleural adenovirus-Cre. Pleural tumors were molecularly phenotyped and cultured to isolate cell lines, which were inoculated into the pleurae of naive mice. Results: K mice developed lethal epithelioid MPM (median, 95%CI survival: 339, 285-379 days). KP mice succumbed to sarcomatoid MPM (median, 95%CI survival 40, 38-72 days) accompanied by MPE (mean±SD volume 349±269 µL). KP mice also developed peritoneal mesothelioma upon intraperitoneal adenovirus-Cre. Mouse MPMs expressed calretinin, podoplanin, and osteopontin, but not surfactant protein C. MPM cell lines were isolated from KP MPM, which transplanted MPM to naiveC57BL/6mice causing their death (median, 95%CI survival 26, 25-28 days) by MPE induction (mean±SD volume 387±180 µL). The models harbored secondary BAP1, NF2 and CDKN2 mutations. Treatment of KP mice with a KRAS inhibitor resulted in increased survival and halted MPM growth and MPE formation. Conclusions: We developed multiple models of primary and transplantable MPM that show thatKRASandTP53mutations can initiate the disease and cause secondaryBAP1andNF2loss. Funding ERC Grants #260524 and #679345.

Malignant pleural effusion (MPE) is the lethal consequence of various human cancers metastatic to the pleural cavity. However, the mechanisms responsible for the development of MPE are still obscure. Here we show that mutant KRAS is important for MPE induction in mice. Pleural disseminated, mutant KRAS bearing tumour cells upregulate and systemically release chemokine ligand 2 (CCL2) into the bloodstream to mobilize myeloid cells from the host bone marrow to the pleural space via the spleen. These cells promote MPE formation, as indicated by splenectomy and splenocyte restoration experiments. In addition, KRAS mutations are frequently detected in human MPE and cell lines isolated thereof, but are often lost during automated analyses, as indicated by manual versus automated examination of Sanger sequencing traces. Finally, the novel KRAS inhibitor deltarasin and a monoclonal antibody directed against CCL2 are equally effective against an experimental mouse model of MPE, a result that holds promise for future efficient therapies against the human condition., Malignant pleural effusion (MPE) is a lethal condition associated with various cancers. Here, the authors show that cancer cells with KRAS mutations promote MPE by recruiting myeloid cells via CCL2 signalling and that pharmaceutical targeting of KRAS results in reduced MPE incidence and volume in mouse models.

The lungs are frequently affected by cancer metastasis. Although NRAS mutations have been associated with metastatic potential, their exact role in lung homing is incompletely understood. We cross‐examined the genotype of various tumor cells with their ability for automatic pulmonary dissemination, modulated NRAS expression using RNA interference and NRAS overexpression, identified NRAS signaling partners by microarray, and validated them using Cxcr1‐ and Cxcr2‐deficient mice. Mouse models of spontaneous lung metastasis revealed that mutant or overexpressed NRAS promotes lung colonization by regulating interleukin‐8‐related chemokine expression, thereby initiating interactions between tumor cells, the pulmonary vasculature, and myeloid cells. Our results support a model where NRAS‐mutant, chemokine‐expressing circulating tumor cells target the CXCR1‐expressing lung vasculature and recruit CXCR2‐expressing myeloid cells to initiate metastasis. We further describe a clinically relevant approach to prevent NRAS‐driven pulmonary metastasis by inhibiting chemokine signaling. In conclusion, NRAS promotes the colonization of the lungs by various tumor types in mouse models. IL‐8‐related chemokines, NRAS signaling partners in this process, may constitute an important therapeutic target against pulmonary involvement by cancers of other organs.

Malignant pleural mesothelioma (MPM) is a highly aggressive tumor caused by asbestos. Faithful mouse models of the disease are missing. Our aim was to develop and characterize a conditional and transplantable mouse model of MPM. Conditional mutant KRAS -expressing ( LSL.KRAS G12D ; K) and TRP53 -deleted ( Trp53 f/f ; P) mice were intercrossed in all possible combinations, followed by intrapleural adenovirus-Cre. Efficient and widespread pleural recombination was verified using dual fluorescent Cre-reporter mice. Multiple cell lines were derived from primary MPM from KP mice and transplanted to C57BL/6 mice. KP mice developed multifocal lethal (median, 95%CI survival 40, 38-72 days) MPM with malignant pleural effusions (MPE; mean±SD volume 349±269 μL) involving both the visceral and parietal pleura and the mediastinum. KP-MPM expresses classical markers of human MPM and gives rise to multiple MPM cell lines (KPM). KPM are transplantable to C57BL/6 mice, leading to death (median, 95%CI survival 26, 25-28 days) and MPE (mean±SD volume 387±180 μL). Δ KRAS could be the tumor initiating gene of malignant pleural mesothelioma development and could present an important therapeutic target. European Research Council Starting Independent Investigator (#260524) and Proof-of-Concept (#679345) Grants.