Identification of Small-Molecule Inhibitors Targeting Different Signaling Pathways in Cancer-Associated Fibroblast Reprogramming Under Tumor-Stroma Interaction.

Cancer-associated fibroblasts (CAFs) interact reciprocally with tumor cells through various signaling pathways in many cancer types including cutaneous squamous cell carcinoma (cSCC). Among normal fibroblast (NF) subtypes, papillary fibroblasts (PFs) and reticular fibroblasts (RFs) respond distinctly to tumor cell signaling, eventuating the differentiation of RFs, rather than PFs, into CAFs. The regulation of subtype differentiation in fibroblasts remains poorly explored. In this study, we assessed the differences between PFs, RFs, and CAFs, and examined the effects of small-molecule inhibitors targeting the TGFß, PI3K/AKT/mTOR, and NOTCH pathways on the tumor-promoting property of CAFs and CAF reprogramming in 2D and 3D cultures. Blocking TGFß and PI3K strongly deactivated and concurrently induced a PF phenotype in RFs and CAFs. 3D co-culturing a cSCC cell line MET2 with RFs or CAFs led to enhanced tumor invasion, "RF-CAF" transition and cytokine production, which were further repressed by blocking TGFß and PI3K/mTOR pathways, but not NOTCH pathway. In conclusion, the study identified biomarkers for PFs, RFs and CAFs, and displayed different effects of blocking key signaling pathways in CAFs and tumor cell-CAF interplay. These findings prompted a "CAF to PF" therapeutic strategy, and provided perspectives of using included inhibitors in CAF-based cancer therapy.

Characterisation of premature cell senescence in Alzheimer's disease using single nuclear transcriptomics.

Aging is associated with cell senescence and is the major risk factor for AD. We characterized premature cell senescence in postmortem brains from non-diseased controls (NDC) and donors with Alzheimer's disease (AD) using imaging mass cytometry (IMC) and single nuclear RNA (snRNA) sequencing (> 200,000 nuclei). We found increases in numbers of glia immunostaining for galactosidase beta (> fourfold) and p16INK4A (up to twofold) with AD relative to NDC. Increased glial expression of genes related to senescence was associated with greater ß-amyloid load. Prematurely senescent microglia downregulated phagocytic pathways suggesting reduced capacity for ß-amyloid clearance. Gene set enrichment and pseudo-time trajectories described extensive DNA double-strand breaks (DSBs), mitochondrial dysfunction and ER stress associated with increased ß-amyloid leading to premature senescence in microglia. We replicated these observations with independent AD snRNA-seq datasets. Our results describe a burden of senescent glia with AD that is sufficiently high to contribute to disease progression. These findings support the hypothesis that microglia are a primary target for senolytic treatments in AD.

A single nuclear transcriptomic characterisation of mechanisms responsible for impaired angiogenesis and blood-brain barrier function in Alzheimer's disease.

Brain perfusion and blood-brain barrier (BBB) integrity are reduced early in Alzheimer's disease (AD). We performed single nucleus RNA sequencing of vascular cells isolated from AD and non-diseased control brains to characterise pathological transcriptional signatures responsible for this. We show that endothelial cells (EC) are enriched for expression of genes associated with susceptibility to AD. Increased ß-amyloid is associated with BBB impairment and a dysfunctional angiogenic response related to a failure of increased pro-angiogenic HIF1A to increased VEGFA signalling to EC. This is associated with vascular inflammatory activation, EC senescence and apoptosis. Our genomic dissection of vascular cell risk gene enrichment provides evidence for a role of EC pathology in AD and suggests that reducing vascular inflammatory activation and restoring effective angiogenesis could reduce vascular dysfunction contributing to the genesis or progression of early AD.

The development of in vitro organotypic 3D vulvar models to study tumor-stroma interaction and drug efficacy.

BACKGROUND: Vulvar squamous cell carcinoma (VSCC) is a rare disease with a poor prognosis. To date, there's no proper in vitro modeling system for VSCC to study its pathogenesis or for drug evaluation. METHODS: We established healthy vulvar (HV)- and VSCC-like 3D full thickness models (FTMs) to observe the tumor-stroma interaction and their applicability for chemotherapeutic efficacy examination. VSCC-FTMs were developed by seeding VSCC tumor cell lines (A431 and HTB117) onto dermal matrices harboring two NF subtypes namely papillary fibroblasts (PFs) and reticular fibroblasts (RFs), or cancer-associated fibroblasts (CAFs) while HV-FTMs were constructed with primary keratinocytes and fibroblasts isolated from HV tissues. RESULTS: HV-FTMs highly resembled HV tissues in terms of epidermal morphogenesis, basement membrane formation and collagen deposition. When the dermal compartment shifted from PFs to RFs or CAFs in VSCC-FTMs, tumor cells demonstrated more proliferation, EMT induction and stemness. In contrast to PFs, RFs started to lose their phenotype and express robust CAF-markers α-SMA and COL11A1 under tumor cell signaling induction, indicating a favored 'RF-to-CAF' transition in VSCC tumor microenvironment (TME). Additionally, chemotherapeutic treatment with carboplatin and paclitaxel resulted in a significant reduction in tumor-load and invasion in VSCC-FTMs. CONCLUSION: We successfully developed in vitro 3D vulvar models mimicking both healthy and tumorous conditions which serve as a promising tool for vulvar drug screening programs. Moreover, healthy fibroblasts demonstrate heterogeneity in terms of CAF-activation in VSCC TME which brings insights in the future development of novel CAF-based therapeutic strategies in VSCC.

Trichothiodystrophy-associated MPLKIP maintains DBR1 levels for proper lariat debranching and ectodermal differentiation.

The brittle hair syndrome Trichothiodystrophy (TTD) is characterized by variable clinical features, including photosensitivity, ichthyosis, growth retardation, microcephaly, intellectual disability, hypogonadism, and anaemia. TTD-associated mutations typically cause unstable mutant proteins involved in various steps of gene expression, severely reducing steady-state mutant protein levels. However, to date, no such link to instability of gene-expression factors for TTD-associated mutations in MPLKIP/TTDN1 has been established. Here, we present seven additional TTD individuals with MPLKIP mutations from five consanguineous families, with a newly identified MPLKIP variant in one family. By mass spectrometry-based interaction proteomics, we demonstrate that MPLKIP interacts with core splicing factors and the lariat debranching protein DBR1. MPLKIP-deficient primary fibroblasts have reduced steady-state DBR1 protein levels. Using Human Skin Equivalents (HSEs), we observed impaired keratinocyte differentiation associated with compromised splicing and eventually, an imbalanced proteome affecting skin development and, interestingly, also the immune system. Our data show that MPLKIP, through its DBR1 stabilizing role, is implicated in mRNA splicing, which is of particular importance in highly differentiated tissue.

Cerebral Vasospasm After Subarachnoid Hemorrhage: Respective Short-Term Effects of Induced Arterial Hypertension and its Combination With IV Milrinone: A Proof-of-Concept Study Using Transcranial Doppler Ultrasound.

OBJECTIVES: It is unclear whether IV milrinone relaxes spasmed cerebral arteries and therefore reduces cerebral blood mean velocity (Vmean). In patients treated for cerebral vasospasm, we aimed to assess and delineate the respective impacts of induced hypertension and its combination with IV milrinone on cerebral hemodynamics as assessed with transcranial Doppler. DESIGN: Observational proof-of-concept prospective study. SETTING: ICU in a French tertiary care center. PATIENTS: Patients with aneurysmal subarachnoid hemorrhage who received induced hypertension (mean arterial blood pressure [MBP] of 100-120 mm Hg) and IV milrinone (0.5 µg/kg/min) for moderate-to-severe cerebral vasospasm. We excluded patients who underwent invasive angioplasty or milrinone discontinuation within 12 hours after the diagnosis of vasospasm. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Vmean was measured at vasospasm diagnosis (TDIAGNOSIS), after the induction of hypertension (THTN), and 1 (THTN+MILRINONE_H1) and 12 hours after the adjunction of IV milrinone (THTN+MILRINONE_H12). Thirteen patients were included. Median Vmean was significantly lower (p < 0.01) at THTN+MILRINONE_H1 (99 [interquartile range (IQR) 89; 134] cm.s-1) and THTN+MILRINONE_H12 (85 [IQR 73-127] cm/s) than at TDIAGNOSIS (136 [IQR 115-164] cm/s) and THTN (148 [IQR 115-183] cm/s), whereas TDIAGNOSIS and THTN did not significantly differ. In all patients but one, Vmean at THTN+MILRINONE_H1 was lower than its value at TDIAGNOSIS (p = 0.0005). Vmean-to-MBP and Vmean-to-cardiac output (CO) ratios (an assessment of Vmean regardless of the level of MBP [n = 13] or CO [n = 7], respectively) were, respectively, similar at TDIAGNOSIS and THTN but were significantly lower after the adjunction of milrinone (p < 0.01). CONCLUSIONS: The induction of arterial hypertension was not associated with a significant decrease in Vmean, whereas the adjunction of IV milrinone was, regardless of the level of MBP or CO. This suggests that IV milrinone may succeed in relaxing spasmed arteries.

Mild and Functional Group-Tolerant Aerobic N-Dealkylation of Tertiary Amines Promoted by Photoredox Catalysis.

This article describes the development of a mild method for the N-dealkylation of tertiary amines via photoredox catalysis and its application in late-stage functionalization. Using the developed method, more than 30 diverse aliphatic, aniline-type, and complex substrates are shown to undergo N-dealkylation, providing a method with broader functional group tolerance compared to methods found in the literature. The scope also includes tertiary and secondary amine molecules with complex substructures and drug substrates. Interestingly, α-oxidation to imines was observed in several cyclic substructures instead of N-dealkylation, suggesting that imines are relevant reaction intermediates.

Accessing Diverse Azole Carboxylic Acid Building Blocks via Mild C-H Carboxylation: Parallel, One-Pot Amide Couplings and Machine-Learning-Guided Substrate Scope Design.

This manuscript describes a mild, functional group tolerant, and metal-free C-H carboxylation that enables direct access to azole-2-carboxylic acids, followed by amide coupling in one pot. This demonstrates a significant expansion of the accessible chemical space of azole-2-amides, compared to previously known methodologies. Key to the described reactivity is the use of silyl triflate reagents, which serve as reaction mediators in C-H deprotonation and stabilizers of (otherwise unstable) azole carboxylic acid intermediates. A diverse azole substrate scope designed via machine-learning-guided analysis demonstrates the broad utility of the sequence. Density functional theory calculations provide detailed insights into the role of silyl triflates in the reaction mechanism. Transferrable applications of the protocol are successfully established: (i) A low pressure (CO2 balloon) option for synthesizing azole-2-carboxylic acids without the need for high-pressure equipment; (ii) the use of 13CO2 for the synthesis of labeled compounds; (iii) isocyanates as alternative electrophiles for direct C-H amidation; (iv) and the use of the developed chemistry in a 24 × 12 parallel synthesis workflow with a 90% library success rate. Fundamentally, the reported protocol expands the use of heterocycle C-H functionalization from late-stage functionalization applications toward its use in library synthesis. It provides general access to densely functionalized azole-2-carboxylic acid building blocks and demonstrates their one-pot diversification.

Transcriptomic changes in autophagy-related genes are inversely correlated with inflammation and are associated with multiple sclerosis lesion pathology.

Autophagy is a lysosomal degradative pathway essential for maintaining cellular homeostasis and is also implicated in multiple aspects of both innate and adaptive immunity. Neuroinflammation, along with demyelination and axonal loss, is an important component of multiple sclerosis (MS). Induction of autophagy ameliorated disease progression in experimental autoimmune encephalomyelitis (EAE), a mouse model for MS, underlying a possible link between autophagy and MS pathology. However, it is still unclear how autophagy is affected during different stages of MS. Here, we show a decreased expression of the autophagy-related (ATG) genes during the acute phase of EAE development in mice as well as in mixed active/inactive lesions of post-mortem human MS brain tissues. Using spatial transcriptomics, we observed that this decreased ATG gene expression is most prominent in the core of mixed active/inactive lesions. Furthermore, we observed a hyper-activation of the mammalian target of rapamycin complex 1 (mTORC1) in lesions, which could inhibit both the initiation of autophagy and the transcription factors that regulate the expression of the ATG genes. Thus, based on our data, we propose a negative regulation of autophagy in MS, possibly through persistent mTORC1 activation, which depends on the lesion stage. Our results contribute to the understanding of the role of autophagy in different stages of MS pathology and point to the mTORC1 pathway as a potential modulator that likely regulates central nervous system (CNS) homeostasis and neuroinflammation in MS.

Asymmetric Synthesis of Tertiary and Secondary Cyclopropyl Boronates via Cyclopropanation of Enantioenriched Alkenyl Boronic Esters.

The cyclopropanation of alkenyl boronates and subsequent derivatization of the boronate handle are a convenient strategy to quickly build molecular complexity and access diverse compounds with a high sp3 fraction. Herein, we describe the asymmetric cyclopropanation of enantioenriched hydrobenzoin-derived alkenyl boronic esters toward the synthesis of tertiary and secondary cyclopropyl boronates.

Brain macrophages acquire distinct transcriptomes in multiple sclerosis lesions and normal appearing white matter.

Multiple sclerosis (MS) is a disease of the central nervous system that is characterized by inflammation and focal areas of demyelination, ultimately resulting in axonal degradation and neuronal loss. Several lines of evidence point towards a role for microglia and other brain macrophages in disease initiation and progression, but exactly how lesion formation is triggered is currently unknown. Here, we characterized early changes in MS brain tissue through transcriptomic analysis of normal appearing white matter (NAWM). We found that NAWM was characterized by enriched expression of genes associated with inflammation and cellular stress derived from brain macrophages. Single cell RNA sequencing confirmed a stress response in brain macrophages in NAWM and identified specific microglia and macrophage subsets at different stages of demyelinating lesions. We identified both phagocytic/activated microglia and CAM clusters that were associated with various MS lesion types. These overall changes in microglia and macrophages associated with lesion development in MS brain tissue may provide therapeutic targets to limit lesion progression and demyelination.

Conformational surveillance of Orai1 by a rhomboid intramembrane protease prevents inappropriate CRAC channel activation.

Calcium influx through plasma membrane calcium release-activated calcium (CRAC) channels, which are formed of hexamers of Orai1, is a potent trigger for many important biological processes, most notably in T cell-mediated immunity. Through a bioinformatics-led cell biological screen, we have identified Orai1 as a substrate for the rhomboid intramembrane protease RHBDL2. We show that RHBDL2 prevents stochastic calcium signaling in unstimulated cells through conformational surveillance and cleavage of inappropriately activated Orai1. A conserved disease-linked proline residue is responsible for RHBDL2's recognizing the active conformation of Orai1, which is required to sharpen switch-like signaling triggered by store-operated calcium entry. Loss of RHBDL2 control of CRAC channel activity causes severe dysregulation of downstream CRAC channel effectors, including transcription factor activation, inflammatory cytokine expression, and T cell activation. We propose that this surveillance function may represent an ancient activity of rhomboid proteases in degrading unwanted signaling proteins.

Lewis acid mediated, mild C-H aminoalkylation of azoles via three component coupling.

This manuscript reports the development of a mild, highly functional group tolerant and metal-free C-H aminoalkylation of azoles via a three-component coupling approach. This method enables the C-H functionalization of diverse azole substrates, such as oxazoles, benzoxazoles, thiazoles, benzothiazoles, imidazoles, and benzimidazoles. DFT calculations identify a key deprotonation equilibrium in the mechanism of the reaction. Using DFT as a predictive tool, the C-H aminoalkylation of initially unreactive substrates (imidazoles/benzimidazoles) can be enabled through an in situ protecting/activating group strategy. The DFT-supported mechanistic pathway proposes key interactions between the azole substrate and the Lewis acid/base pair TBSOTf/EtNiPr2 that lead to azole activation by deprotonation, followed by C-C bond formation between a carbene intermediate and an iminium electrophile. Two diverse approaches are demonstrated to explore the amine substrate scope: (i) a DFT-guided predictive analysis of amine components that relates reactivity to distortion of the iminium intermediates in the computed transition state structures; and (ii) a parallel medicinal chemistry workflow enabling synthesis and isolation of several diversified products at the same time. Overall, the presented work enables a metal-free approach to azole C-H functionalization via Lewis acid mediated azole C-H deprotonation, demonstrating the potential of a readily available, Si-based Lewis acid to mediate new C-C bond formations.

Systems analysis and controlled malaria infection in Europeans and Africans elucidate naturally acquired immunity.

Controlled human infections provide opportunities to study the interaction between the immune system and malaria parasites, which is essential for vaccine development. Here, we compared immune signatures of malaria-naive Europeans and of Africans with lifelong malaria exposure using mass cytometry, RNA sequencing and data integration, before and 5 and 11 days after venous inoculation with Plasmodium falciparum sporozoites. We observed differences in immune cell populations, antigen-specific responses and gene expression profiles between Europeans and Africans and among Africans with differing degrees of immunity. Before inoculation, an activated/differentiated state of both innate and adaptive cells, including elevated CD161+CD4+ T cells and interferon-γ production, predicted Africans capable of controlling parasitemia. After inoculation, the rapidity of the transcriptional response and clusters of CD4+ T cells, plasmacytoid dendritic cells and innate T cells were among the features distinguishing Africans capable of controlling parasitemia from susceptible individuals. These findings can guide the development of a vaccine effective in malaria-endemic regions.

Searching beyond the Lamppost to Reduce Breast Cancer Disparities.

Racial and ethnic differences in breast cancer occur by race/ethnicity in both incidence and mortality rates. Women of lower socioeconomic status likewise have poorer outcomes. When race alone is considered, incidence rates in the United States are highest among White women (130.8 per 100,000), with Black women close behind (126.7 per 100,000). Incidence is lowest among Asian/Pacific Islander women, at 93.2 per 100,000. Mortality differences are more pronounced, with Black women 40% more likely to die from breast cancer than White women (28.4 per 100,000 and 20.3 per 100,000, respectively). Mortality rates for Asian/Pacific Islander women (11.5 per 100,000) are far lower than for Black and White women. When age is considered, additional differences between Black and White women appear, in part accounted for by types of breast cancer experienced. Women of other racial/ethnic groups and socioeconomic status have received less scientific attention. In this article, we provide a brief overview of the evidence for social determinants of breast cancer and argue that the current reliance on race over racism and ethnicity contributes to our inability to eliminate breast cancer disparities in the United States and elsewhere in the world. We suggest alternatives to the current approach to research in breast cancer disparities.

The effect of TGFßRI inhibition on fibroblast heterogeneity in hypertrophic scar 2D in vitro models.

In burn patients, wound healing is often accompanied by hypertrophic scarring (HTS), resulting in both functional and aesthetic problems. HTSs are characterized by abundant presence of myofibroblasts (MFs) residing in the dermis. HTS development and MF persistence is primarily regulated by TGF-ß signalling. A promising method to target the transforming growth factor receptor I (TGFßRI; also known as activin-like kinase 5 (ALK5)) is by making use of exon skipping through antisense oligonucleotides. In HTS the distinguishing border between the papillary dermis and the reticular dermis is completely abrogated, thus exhibiting a one layered dermis containing a heterogenous fibroblast population, consisting of papillary fibroblasts (PFs), reticular fibroblasts (RFs) and MFs. It has been proposed that PFs, as opposed to RFs, exhibit anti-fibrotic properties. Currently, it is still unclear which fibroblast subtype is most affected by exon skipping treatment. Therefore, the aim of this study was to investigate the effect of TGFßRI inhibition by exon skipping in PF, RF and HTS fibroblast monocultures. Morphological analyses revealed the presence of a PF-like population after exon skipping in the different fibroblast cultures. This observation was further confirmed by the expression of genes specific for PFs, demonstrated by qPCR analyses. Further investigations on mRNA and protein level revealed that indeed MFs and to a lesser extent RFs are targeted by exon skipping. Furthermore, collagen gel contraction analysis showed that ALK5 exon skipping reduced TGF-ß- induced contraction together with decreased alpha-smooth muscle actin expression levels. In conclusion, we show for the first time that exon skipping primarily targets pro-fibrotic fibroblasts. This could be a promising step towards reduced HTS development of burn tissue.

Iron-Catalyzed α-C-H Cyanation of Simple and Complex Tertiary Amines.

This manuscript details the development of a general and mild protocol for the α-C-H cyanation of tertiary amines and its application in late-stage functionalization. Suitable substrates include tertiary aliphatic, benzylic, and aniline-type substrates and complex substrates. Functional groups tolerated under the reaction conditions include various heterocycles and ketones, amides, olefins, and alkynes. This broad substrate scope is remarkable, as comparable reaction protocols for α-C-H cyanation frequently occur via free radical mechanisms and are thus fundamentally limited in their functional group tolerance. In contrast, the presented catalyst system tolerates functional groups that typically react with free radicals, suggesting an alternative reaction pathway. All components of the described catalyst system are readily available, allowing implementation of the presented methodology without the need for lengthy catalyst synthesis.

Californians Linking Action with Science for Prevention of Breast Cancer (CLASP-BC)-Phase 2.

Californians Linking Action with Science for Prevention of Breast Cancer (CLASP-BC) is part of California Breast Cancer Research Program's (CBCRP) Initiative strategic priority to disseminate and implement high-impact, population-based primary prevention interventions. CLASP-BC is informed by six years of funded program dissemination and implementation (D&I) research and evaluation conducted by the Canadian Partnership Against Cancer (CPAC) through its Coalitions Linking Action and Science for Prevention (CLASP). In its second phase, CLASP-BC will fund multi-sector, multi-jurisdictional initiatives that integrate the lessons learned from science with the lessons learned from practice and policy to reduce the risk of developing breast cancer and develop viable and sustainable infrastructure models for primary prevention breast cancer programs and research evidence implementation. Applications will be solicited from research, practice, policy, and community teams to address one or more of the intervention goals for the 23 risk factors identified in Paths to Prevention: The California Breast Cancer Primary Prevention Plan (P2P), expanding upon existing primary prevention efforts into two or more California jurisdictions, focused on disadvantaged, high risk communities with unmet social needs. The lessons learned from CLASP-BC will be widely disseminated within the participating jurisdictions, across California and, where applicable, to jurisdictions outside the state.

High-Resolution Transcriptomic and Proteomic Profiling of Heterogeneity of Brain-Derived Microglia in Multiple Sclerosis.

Microglia are important for central nervous system (CNS) homeostasis and first to respond to tissue damage and perturbations. Microglia are heterogeneous cells; in case of pathology, microglia adopt a range of phenotypes with altered functions. However, how these different microglia subtypes are implicated in CNS disease is largely unresolved. Multiple sclerosis (MS) is a chronic demyelinating disease of the CNS, characterized by inflammation and axonal degeneration, ultimately leading to neurological decline. One way microglia are implicated in MS is through stimulation of remyelination. They facilitate efficient remyelination by phagocytosis of myelin debris. In addition, microglia recruit oligodendrocyte precursor cells (OPCs) to demyelinated areas and stimulate remyelination. The development of high-resolution technologies to profile individual cells has greatly contributed to our understanding of microglia heterogeneity and function under normal and pathological conditions. Gene expression profiling technologies have evolved from whole tissue RNA sequencing toward single-cell or nucleus sequencing. Single microglia proteomic profiles are also increasingly generated, offering another layer of high-resolution data. Here, we will review recent studies that have employed these technologies in the context of MS and their respective advantages and disadvantages. Moreover, recent developments that allow for (single) cell profiling while retaining spatial information and tissue context will be discussed.

Doing What We Know, Knowing What to Do: Californians Linking Action with Science for Prevention of Breast Cancer (CLASP-BC).

Given the lack of progress in breast cancer prevention, the California Breast Cancer Research Program (CBCRP) plans to apply current scientific knowledge about breast cancer to primary prevention at the population level. This paper describes the first phase of Californians Linking Action with Science for Prevention of Breast Cancer (CLASP-BC). The foci of Phase 1 are building coalitions and coalition capacity building through community engagement in community-based participatory research (CBPR) and dissemination and implementation (D&I) research training. Based on the successful implementation and evaluation of Phase 1, the foci of Phase 2 (presented separately in this special issue) will be to translate the California Breast Cancer Prevention Plan overarching goal and specific intervention goals for 23 breast cancer risk and protective factors strategies into evidence-informed interventions (EIIs) that are disseminated and implemented across California. CLASP-BC is designed to identify, disseminate and implement high-impact, population-based prevention approaches by funding large scale EIIs, through multi-jurisdictional actions, with the intent to decrease the risk of breast cancer and other chronic diseases (sharing common risk factors), particularly among racial/ethnic minorities and medically underserved populations in California.