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Reichert, M.

Publications and source records attributed to Reichert, M..

14 recordsLinked to original sources

Multimodal longitudinal prediction of alcohol-use trajectories in adolescents and young adults: Social context, real-life social affective benefit, and fronto-striatal involvement

Escalating alcohol use during adolescence and young adulthood confers substantial risk for later substance misuse and adverse mental health outcomes, yet the factors that determine early drinking trajectories remain poorly understood. Here, we examined alcohol use across social, affective, and neural domains in a cohort of 378 community-based young drinkers using a combination of longitudinal phenotyping, ecological momentary assessment (EMA) and functional neuroimaging. Across different levels of analysis, higher baseline alcohol consumption (standard drinks per week) was associated with immediate substance-use social context, greater social-affective benefit in daily life, and heightened engagement of the fronto-striatal reward circuitry. In a one-year longitudinal follow-up, individual social-affective benefit and substance-related social environmental factors showed the strongest predictive value for drinking trajectories in a follow-up of 219 individuals after one year. Our findings identify key social and neural reward-related determinants of youth drinking behavior, informing the development of evidence-based risk detection and prevention measures.

neuroscience↗

Neurostructural correlates of real-life social drinking risk in alcohol use disorder

The social context of alcohol consumption is increasingly recognized as an important factor in the development of alcohol use disorder (AUD). However, individuals with AUD may differ in how strongly alcohol use by people around them is associated with their own drinking, and the neurostructural basis of this variation remains unclear. Here we studied 83 individuals with AUD (53 men, 30 women; mean [SD] age, 37.20 [12.42] years; median DSM-5 AUD criteria, 4) using six weeks of ecological momentary assessment and structural magnetic resonance imaging (n = 80). Across 5,221 non-solitary observations, greater exposure to surrounding drinkers was associated with increased odds of momentary drinking (odds ratio, 4.23; 95% CI, 3.60-4.97), with significant between-person variation that we quantified as social drinking risk (SDR). Higher SDR was associated with lower gray matter volume in the pregenual anterior cingulate cortex (T = 5.40; P < .001) and weaker pregenual anterior cingulate cortex-ventral striatum structural covariance (T = 3.15; P = .032). These findings support SDR as an ecologically grounded phenotype linking daily-life social-context sensitivity to cingulostriatal structure, with potential relevance for mechanistic and interventional research in AUD.

neuroscience↗

Modeling pancreatic cancer tumor stroma co-evolution in an in ovo model

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a dense, desmoplastic microenvironment that drives disease progression, yet conventional models fail to capture this complex tumor-stroma coevolution. Here, we utilize the chick chorioallantoic membrane (CAM) platform to investigate tumor-stroma interactions using murine PDAC cell lines and patient-derived organoids (PDOs). Integrating single-cell RNA sequencing and spatial transcriptomics, we show that the CAM microenvironment supports the emergence of complex tumor ecosystems while preserving patient-specific characteristics. Within five days, in ovo tumors faithfully recapitulated the structural and molecular features of parental tumors. Histological analysis revealed the rapid recruitment and spatial organization of heterogeneous host cancer-associated fibroblast (CAF) populations, showcasing distinct myofibroblastic and inflammatory stromal states. Crucially, the model preserved intrinsic tumor heterogeneity and permitted functional interrogation of subtype-specific extracellular matrix remodeling and metastatic dissemination. Together, our findings demonstrate that the CAM provides a highly permissive niche for tumor-stroma coevolution. As a rapid, scalable, and biologically relevant platform, this in ovo model offers a powerful approach for studying stromal composition, metastatic progression, and patient-specific tumor biology in pancreatic cancer.

cancer biology↗

Fish remain high in selenium long after mountaintop coal mines close

Mountaintop removal (MTR) coal mining generates large volumes of waste rock. Weathering of this waste rock releases selenium, which can bioaccumulate to levels that can harm, and even extirpate, downstream fish communities. This is well demonstrated in ecosystems impacted by active MTR operations; however, less is known about the long-term impacts after coal mines close. Here we show that MTR coal mines still present an acute threat to downstream fish populations, decades after mining ends. Crowsnest Lake (Alberta, Canada) receives runoff from the Tent Mountain Coal Mine, which closed in the 1980s and part of which was certified reclaimed. Fish in Crowsnest Lake contain tissue selenium concentrations (5-26 {micro}g/g dry weight) that exceed guidelines and rival fish selenium levels downstream of active MTR operations. This is despite lake water selenium concentrations ([&le;]2 {micro}g/L) that are below water quality guidelines intended to protect fish. The clinical signs of selenium poisoning in fish are similar to the symptoms of Whirling Disease, which was first detected in the Crowsnest basin in 2016 making this the first aquatic system to be impacted by both stressors. This finding demonstrates that the biological impacts of MTR coal mining can persist long after mining operations end, and it suggests that any further coal mine development may well push the Crowsnest fishery beyond sustainability. SynopsisFish in Crowsnest Lake, Alberta, are high in selenium sourced from an abandoned mountaintop removal coal mine.

ecology↗

Accelerated maturation of branched organoids confined in collagen droplets

Droplet-based organoid culture offers several advantages over conventional bulk organoid culture, such as improved yield, reproducibility, and throughput. However, organoids grown in droplets typically display only a spherical geometry and lack the intricate structural complexity found in native tissue. By incorporating singularized pancreatic ductal adenocarcinoma cells into collagen droplets, we achieve the growth of branched structures, indicating a more complex interaction with the surrounding hydrogel. A comparison of organoid growth in droplets of different diameters showed that while geometrical confinement improves organoid homogeneity, it also impairs the formation of more complex organoid morphologies. Thus, only in 750 {micro}m diameter collagen droplets did we achieve the consistent growth of highly branched structures with a morphology closely resembling the structural complexity achieved in traditional bulk organoid culture. Moreover, our analysis of organoid morphology and transcriptomic data suggests an accelerated maturation of organoids cultured in collagen droplets, highlighting a shift in developmental timing compared to traditional systems.

bioengineering↗

c-Rel drives pancreatic cancer metastasis through Fibronectin-Integrin signaling-induced isolation stress resistance and EMT activation

Pancreatic ductal adenocarcinoma remains one of the deadliest malignancies, with limited treatment options and a high recurrence rate. Recurrence happens often with metastasis, for which cancer cells must adapt to isolation stress to successfully colonize distant organs. While the fibronectin-integrin axis has been implicated in this adaptation, its regulatory mechanisms require further elaboration. Here, we identify c-Rel as an oncogenic driver in PDAC, promoting epithelial-to-mesenchymal transition (EMT) plasticity, extracellular matrix (ECM) remodeling, and resistance to isolation stress. Mechanistically, c-Rel directly regulates fibronectin (Fn1) and CD61 (itgb3) transcription, enhancing cellular plasticity and survival under anchorage-independent conditions. Fibronectin is not essential for EMT, but its absence significantly impairs metastatic colonization, highlighting a tumor-autonomous role for FN1 in isolation stress adaptation. These findings establish c-Rel as a key regulator of PDAC metastasis by controlling circulating tumor cell (CTC) niche and survival, suggesting that targeting the c-Rel-fibronectin-integrin axis could provide new therapeutic strategies to mitigate disease progression and recurrence.

cancer biology↗

Engineering de novo binder CAR-T cell therapies with generative AI

Chimeric antigen receptor T cell (CAR-T) therapies have revolutionized cancer treatment, with six CAR-T products currently in clinical use1-4. Despite their success, high resistance rates due to antigen escape remain a major challenge5,6. In silico design of de novo binders (DNBs) has the potential to accelerate the development of new binding domains for CAR-T, possibly enabling personalized therapies for cancer resistance7,8. Here, we show that DNBs can be used for CAR-T, targeting clinically relevant cancer antigens. Using a DNB against the epidermal growth factor receptor (EGFR), we demonstrate comparable cytotoxicity, cytokine secretion, long-term proliferation, and lysis of primary patient-derived cancer organoids with single-chain variable fragment (scFv)-based and DNB-based CAR-T cells. Moreover, we use generative artificial intelligence (AI) guided binder design with RFdiffusion9 to target the B cell maturation antigen (BCMA), a key antigen in multiple myeloma treatment10-17. We confirmed the activity of our AI-designed BCMA CAR-T in short- and long-term effector readouts, including a xenograft mouse model of multiple myeloma. Notably, our AI-guided CAR-T approach also successfully targets a mutated BCMA protein variant resistant to the clinically used bispecific antibody teclistamab. In sum, we demonstrate a proof-of-concept for engineering new, bespoke cellular immunotherapies targeting cancer resistance with the help of generative AI. This approach may further accelerate the development of new CAR-T therapies addressing cancer resistance.

bioengineering↗

ADAM17 regulates hepatic DNA damage repair and tumour formation

BackgroundHepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide. Still, therapy options for this tumour entity are limited and novel therapeutic options are highly sought after. Genomic instability of hepatocytes promotes oncogenic transformation and underlies the regulation of micro-environmental signalling cues. The membrane-bound a disintegrin and metalloprotease (ADAM) 17 is a major regulator of micro-environmental signals through the proteolytic release of paracrine factors. However, its role in hepatic DNA damage repair and its contribution to hepatic tumourigenesis is still unclear. MethodsWe investigated the effect of ADAM17 on diethylnitrosamine (DEN)-induced acute DNA damage and subsequent DNA damage repair by utilizing mice with ubiquitous or myeloid-specific genetic deficiency in ADAM17. DNA double strand breaks and inflammation were investigated by immunofluorescence of liver tissue sections. tumourigenesis in mice with myeloid-specific ADAM17-deficiency was investigated in a chemically induced hepatocarcinogenesis model. ResultsADAM17 on myeloid cells, in particular Kupffer cells is essentially involved in the non-cell autonomous regulation of DNA damage repair in hepatocytes. Parenchymal ADAM17 regulates hepatocyte fate and recruitment of infiltrating myeloid cells. Furthermore, myeloid ADAM17 promotes hepatic tumour initiation and correlates with poor prognosis in human HCC. ConclusionsWe identified ADAM17, in particular on myeloid cells as an essential driver of hepatic tumourigenesis and as a potential novel drug target for the treatment of hepatic malignancies.

cancer biology↗

NOXA expression drives synthetic lethality to RUNX1 inhibition in pancreatic cancer

Evasion from drug-induced apoptosis is a crucial mechanism of cancer treatment resistance. The pro-apoptotic protein NOXA marks an aggressive pancreatic ductal adenocarcinoma (PDAC) subtype. To identify drugs that unleash the death-inducing potential of NOXA, we performed an unbiased drug screening experiment. In NOXA-deficient isogenic cellular models we identified an inhibitor of the transcription factor heterodimer CBF{beta}/RUNX1. By genetic gain and loss of function experiments we validated that the mode of action depends on RUNX1 and NOXA. Of note, RUNX1 expression is significantly higher in PDACs compared to normal pancreas. We show that pharmacological RUNX1 inhibition significantly blocks tumor growth in vivo and in primary patient-derived PDAC organoids. Through genome wide analysis, we detected that RUNX1-loss reshapes the epigenetic landscape, which gains H3K27ac enrichment at the NOXA promoter. Our study demonstrates a previously unknown mechanism of NOXA-dependent cell death, which can be triggered pharmaceutically. Therefore, our data show a novel way to target a therapy resistant PDAC, an unmet clinical need. SignificanceRecent evidence demonstrated the existence of molecular subtypes in pancreatic ductal adenocarcinoma (PDAC), which resist all current therapies. The paucity of therapeutic options, including a complete lack of targeted therapies, underscore the urgent and unmet medical need for the identification of targets and novel treatment strategies for PDAC. Our study unravels a function of the transcription factor RUNX1 in apoptosis regulation in PDAC. We show that pharmacological RUNX1 inhibition in PDAC is feasible and leads to NOXA-dependent apoptosis. The development of targeted therapies that influence the transcriptional landscape of PDAC might have great benefits for patients who are resistant to conventional therapies. RUNX1 Inhibition as a new therapeutic intervention offers an attractive strategy for future therapies.

cancer biology↗

Real-time individual benefit from social interactions before and during the lockdown: The crucial role of personality, neurobiology and genes.

BackgroundSocial integration is a major resilience factor for staying healthy. However, the COVID-19-pandemic led to unprecedented restrictions in social life. The consequences of these social lockdowns on momentary well-being are yet not fully understood. MethodWe investigated the individual affective benefit from social interactions in a longitudinal birth cohort study. We used two real-time, real-life ecological momentary assessments once before and once during the initial lockdown of the pandemic (N~6800 total observations) to determine the protective role of social interactions on well-being. Moreover, we used a multimethod approach combining the ecological assessment data with individual risk and resilience factors to analyze the moderating mechanisms of personality, neurobiology and genes. ResultsSocial contacts were linked to higher positive affect both during normal times and during the COVID-19 pandemic, highlighting the beneficial role of social embedding. Moreover, this relationship was moderated by amygdala volume, neuroticism and polygenic risk for schizophrenia. In detail, participants with a larger left amygdala volume and higher trait neuroticism exhibited an affective benefit from more social interactions prior to the pandemic. This pattern changed during the pandemic with participants with smaller amygdala volumes and lower neurotic traits showing a social affective gain during the pandemic. Moreover, participants with low genetic risk for schizophrenia showed an affective benefit from social interactions irrespective of the time point. ConclusionOur results highlight the protective role of social integration on momentary well-being. Thereby, we offer new insights into how this relationship is differently affected by a persons, neurobiology, personality, and genes under adverse circumstances.

neuroscience↗

Autoantibodies against Progranulin and IL-1 receptor antagonist in critically ill COVID-19

STRUCTURED ABSTRACTHyperinflammation is frequently observed in patients with severe COVID-19. Inadequate and defective IFN type I responses against SARS-CoV-2, associated with autoantibodies in a proportion of patients, lead to severe courses of disease. In addition, hyperactive responses of the humoral immune system have been described. In the current study we investigated a possible role of neutralizing autoantibodies against antiinflammatory mediators. Plasma from adult patients with severe and critical COVID-19 was screened by ELISA for antibodies against PGRN, IL-1-Ra, IL-10, IL-18BP, IL-22BP, IL-36-Ra, CD40, IFN-2, IFN-{gamma}, IFN-{omega} and serpinB1. Autoantibodies were characterized and the antigens were analyzed for immunogenic alterations. In a discovery cohort with severe to critical COVID-19 high titers of PGRN-autoantibodies were detected in 11 of 30 (36.7%), and of IL-1-Ra-autoantibodies in 14 of 30 (46.7%) patients. In a validation cohort of 64 patients with critical COVID-19 high-titer PGRN-Abs were detected in 25 (39%) and IL-1-Ra-Abs in 32 of 64 patients (50%). PGRN-Abs and IL-1-Ra-Abs belonged to IgM and several IgG subclasses. In separate cohorts with non-critical COVID-19, PGRN-Abs and IL-1-Ra-Abs were detected in low frequency (i.e. in < 5% of patients) and at low titers. Neither PGRN-nor IL-1-Ra-Abs were found in 40 healthy controls vaccinated against SARS-CoV-2 or 188 unvaccinated healthy controls. PGRN-Abs were not cross-reactive against SARS-CoV-2 structural proteins nor against IL-1-Ra. Plasma levels of both free PGRN and free IL-1-Ra were significantly decreased in autoantibody-positive patients compared to Ab-negative and non-COVID-19 controls. In vitro PGRN-Abs from patients functionally reduced PGRN-dependent inhibition of TNF- signaling, and IL-1-Ra-Abs from patients reduced IL-1-Ra- or anakinra-dependent inhibition of IL-1{beta} signaling. The pSer81 hyperphosphorylated PGRN isoform was exclusively detected in patients with high-titer PGRN-Abs; likewise, a hyperphosphorylated IL-1-Ra isoform was only found in patients with high-titer IL-1-Ra-Abs. Thr111 was identified as the hyperphophorylated amino acid of IL-1-Ra. In longitudinally collected samples hyperphosphorylated isoforms of both PGRN and IL-1-Ra emerged transiently, and preceded the appearance of autoantibodies. In hospitalized patients, the presence of IL-1-Ra-Abs or IL-1-Ra-Abs in combination with PGRN-Abs was associated with a higher morbidity and mortality. To conclude, neutralizing autoantibodies to IL-1-Ra and PGRN occur in a significant portion of patients with critical COVID-19, with a concomitant decrease in circulating free PGRN and IL-1-Ra, indicative of a misdirected, proinflammatory autoimmune response. The break of self-tolerance is likely caused by atypical hyperphosphorylated isoforms of both antigens, whose appearances precede autoantibody induction. Our data suggest that these immunogenic secondary modifications are induced by the SARS-CoV-2-infection itself or the inflammatory environment evoked by the infection and predispose for a critical course of COVID-19.

immunology↗

Phosphoproteomics identifies PI3K inhibitor-selective adaptive responses in pancreatic cancer cell therapy and resistance

The PI3K pathway is highly active in human cancers. The four class I isoforms of PI3K are activated by distinct mechanisms leading to a common downstream signaling. Their downstream redundancy is thought to be responsible for treatment failures of PI3K inhibitors. We challenged this concept, by mapping the differential phosphoproteome evolution in response to PI3K inhibitors with different isoform selectivity patterns in pancreatic cancer, a disease currently without effective therapy. In this cancer, the PI3K signal was shown to control cell proliferation. We compared the effects of LY294002 that inhibit with equal potency all class I isoenzymes and downstream mTOR with the action of inhibitors with higher isoform-selectivity towards PI3K, PI3K{beta} or PI3K{gamma} (namely A66, TGX-221 and AS-252424). A bioinformatics global pathway analysis of phosphoproteomics data allowed us to identify common and specific signals activated by PI3K inhibitors supported by the biological data. AS-252424 was the most effective treatment and induced apoptotic pathway activation as well as the highest changes in global phosphorylation-regulated cell signal. However, AS-252424 treatment induced re-activation of Akt, therefore decreasing the treatment outcome on cell survival. Reversely, AS-252424 and A66 combination treatment prevented p-Akt reactivation and led to synergistic action in cell lines and patient organoids. The combination of clinically approved -selective BYL-719 with {gamma}-selective IPI-549 was more efficient than single molecule treatment on xenograft growth. Mapping unique adaptive signaling responses to isoform-selective PI3K inhibition will help to design better combinative treatments that prevent the induction of selective compensatory signals. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC="FIGDIR/small/313833v3_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@32004eorg.highwire.dtl.DTLVardef@b22f25org.highwire.dtl.DTLVardef@352a98org.highwire.dtl.DTLVardef@7f97a1_HPS_FORMAT_FIGEXP M_FIG C_FIG SignificanceHalf of all human cancers show increased PI3K activity but the mutational pattern of the PI3K pathway is not sufficient to predict sensitivity to PI3K inhibitors. By identifying for the first time specific signaling induced by PI3K inhibitors with different isoform-selectivity patterns, we provide insight in how to handle heterogeneity of PI3K expression in tumor samples for the choice of available PI3K-targetting drugs. Our work provides a roadmap to target the PI3K pathway, balancing the use of isoform-selective PI3K inhibitors with personalized information extending beyond the specific mutational status.

cancer biology↗

Sex-specific speed-accuracy tradeoffs shape neural processing of acoustic signals

Speed-accuracy tradeoffs - being fast at the risk of being wrong - are fundamental to many decisions and natural selection is expected to resolve these tradeoffs according to the costs and benefits of behavior. We here test the prediction that females and males should integrate information from courtship signals differently because they experience different payoffs along the speed-accuracy continuum. We fitted a neural model of decision making (a drift-diffusion model of integration to threshold) to behavioral data from the grasshopper Chorthippus biguttulus to determine the parameters of temporal integration of acoustic directional information used by male grasshoppers to locate receptive females. The model revealed that males had a low threshold for initiating a turning response, yet a large integration time constant enabled them to continue to gather information when cues were weak. This contrasts with parameters estimated for females of the same species when evaluating potential mates, in which response thresholds were much higher and behavior was strongly influenced by unattractive stimuli. Our results reveal differences in neural integration consistent with the sex-specific costs of mate search: Males often face competition and need to be fast, while females often pay high error costs and need to be deliberate.

neuroscience↗

Targeting the ubiquitin-proteasome system in a pancreatic cancer subtype with hyperactive MYC

Purpose The myelocytomatosis oncogene (MYC) is an important driver in a subtype of pancreatic ductal adenocarcinoma (PDAC). However, MYC remains a challenging therapeutic target, therefore identifying druggable synthetic lethal interactions in MYC-active PDAC may lead to novel precise therapies.Methods Cluster analysis using direct MYC target genes was used to identify PDAC with active MYC. We profiled the transcriptome of established human cell lines, murine primary PDAC cell lines and also accessed public available repositories for transcriptomic profiling. Networks active in MYC hyperactive subtypes were analyzed by gene set enrichment analysis. An unbiased pharmacological drug screen with FDA-approved anti-cancer drugs was conducted to define MYC-associated vulnerabilities, which were validated by analysis of drug response repositories and genetic gain- and loss-of-function experiments.Results In an unbiased pharmacological drug screen with FDA-approved anti-cancer drugs we detected that the proteasome inhibitor bortezomib triggers a MYC-associated vulnerability. By integrating publicly available data sets we found the unfolded protein response as a signature connected to MYC. Furthermore, the increased sensitivity of MYC hyperactive PDACs to bortezomib was validated in genetically modified PDAC cells.Conclusions In sum, we provide evidence that perturbing the ubiquitin proteasome system might be an option to target MYC hyperactive PDAC cells and our data provide the rationale to further develop precise targeting of the ubiquitin-proteasome system as a subtype-specific therapeutic approach.Competing Interest StatementThe authors have declared no competing interest.Abbrevations4-OHT4-hydoxytamoxifenATF4activating transcription factor 4BETbromodomain and extra terminal motifCNVcopy number variationCTD2cancer target discovery and development networkdepmapdependency mapDoRothEAdiscriminant regulon expression analysisGSEAgene set enrichment analysisICGCinternational cancer gene consortiumMYCmyelocytomatosis oncogenePDACpancreatic ductal adenocarcinomaPERKproteinkinase RNA-activated-like ER kinaseSUMOsmall-ubiquitin-like modifierTCGAthe cancer genome atlasUPRunfolded protein responseUPSubiquitin proteasome systemView Full Text

cancer biology↗