Expression of LGR5 in mammary myoepithelial cells and in triple-negative breast cancers
Lee, HJ;Myung, JK;Kim, HS;Lee, DH;Go, HS;Choi, JH;Koh, HM;Lee, SJ;Jang, B;
PMID: 34493772 | DOI: 10.1038/s41598-021-97351-y
Lineage tracing in mice indicates that LGR5 is an adult stem cell marker in multiple organs, such as the intestine, stomach, hair follicles, ovary, and mammary glands. Despite many studies exploring the presence of LGR5 cells in human tissues, little is known about its expression profile in either human mammary tissue or pathological lesions. In this study we aim to investigate LGR5 expression in normal, benign, and malignant lesions of the human breast using RNA in situ hybridization. LGR5 expression has not been observed in normal lactiferous ducts and terminal duct lobular units, whereas LGR5-positive cells have been specifically observed in the basal myoepithelium of ducts in the regenerative tissues, ductal carcinoma in situ, and in ducts surrounded by invasive cancer cells. These findings suggest LGR5 marks facultative stem cells that are involved in post injury regeneration instead of homeostatic stem cells. LGR5 positivity was found in 3% (9 of 278 cases) of invasive breast cancers (BC), and it showed positive associations with higher histologic grades (P = 0.001) and T stages (P < 0.001), while having negative correlations with estrogen receptor (P < 0.001) and progesterone receptor (P < 0.001) expression. Remarkably, all LGR5-positive BC, except one, belong to triple-negative BC (TNBC), representing 24% (9 of 38 cases) of all of them. LGR5 histoscores have no correlations with EGFR, CK5/6, Ki-67, or P53 expression. Additionally, no β-catenin nuclear localization was observed in LGR5-positive BC, indicating that canonical Wnt pathway activation is less likely involved in LGR5 expression in BC. Our results demonstrate that LGR5 expression is induced in regenerative conditions in the myoepithelium of human mammary ducts and that its expression is only observed in TNBC subtype among all invasive BC. Further studies regarding the functional and prognostic impact of LGR5 in TNBC are warranted.
Yamazaki, S;Inohara, N;Ohmuraya, M;Tsuneoka, Y;Yagita, H;Katagiri, T;Nishina, T;Mikami, T;Funato, H;Araki, K;Nakano, H;
PMID: 35999460 | DOI: 10.1038/s41385-022-00554-3
Control of gut microbes is crucial for not only local defense in the intestine but also proper systemic immune responses. Although intestinal epithelial cells (IECs) play important roles in cytokine-mediated control of enterobacteria, the underlying mechanisms are not fully understood. Here we show that deletion of IκBζ in IECs in mice leads to dysbiosis with marked expansion of segmented filamentous bacteria (SFB), thereby enhancing Th17 cell development and exacerbating inflammatory diseases. Mechanistically, the IκBζ deficiency results in decrease in the number of Paneth cells and impairment in expression of IL-17-inducible genes involved in IgA production. The decrease in Paneth cells is caused by aberrant activation of IFN-γ signaling and a failure of IL-17-dependent recovery from IFN-γ-induced damage. Thus, the IL-17R-IκBζ axis in IECs contributes to the maintenance of intestinal homeostasis by serving as a key component in a regulatory loop between the gut microbiota and immune cells.
CNS Neuroscience and Therapeutics
Grabon, W;Bodennec, J;Belmeguenai, A;Bezin, L;
: The endocannabinoid system is recognized as an important player in neuromodulation in the central nervous system (CNS). It comprises cannabinoid receptors, endogenous molecules called endocannabinoids (eCBs) that activate these receptors, and enzymes that synthesize and degrade eCBs. 1 The most abundant eCBs are anandamide and 2-arachidoylglycerol. Many effects of eCBs are mediated by type 1 (CB1R) and type 2 (CB2R) cannabinoid receptors, which are the best known and involved in the homeostatic control of several physiological functions in the brain and other organs. 2 CB1R and CB2R are G protein-coupled receptors (GPCRs) that, in addition to interacting with eCBs, are also activated by synthetic and plantderived cannabinoids. Both were cloned in the early 1990s from human leukemia cells. 3,4 However, it is important to note here that we must take a much broader view of this system. Indeed, studies over the last decade have revealed the existence of a wide range of lipid mediators with eCB-like properties, novel enzymes, and new receptors, effectively complicating our picture of the endocannabinoid system and justifying the use of endocannabinoidome to describe it. 5 CB1R is the most prevalent GPCR in the CNS and is expressed extensively by most neuron types. 6 This receptor is the major mediator of the psychoactive effects of Cannabis sativa and its derivatives.
Novellasdemunt, L;Kucharska, A;Baulies, A;Hutton, C;Vlachogiannis, G;Repana, D;Rowan, A;Suárez-Bonnet, A;Ciccarelli, F;Valeri, N;Li, VSW;
PMID: 36669491 | DOI: 10.1016/j.stemcr.2022.12.013
Adenomatous polyposis coli (APC) mutation is the hallmark of colorectal cancer (CRC), resulting in constitutive WNT activation. Despite decades of research, targeting WNT signaling in cancer remains challenging due to its on-target toxicity. We have previously shown that the deubiquitinating enzyme USP7 is a tumor-specific WNT activator in APC-truncated cells by deubiquitinating and stabilizing β-catenin, but its role in gut tumorigenesis is unknown. Here, we show in vivo that deletion of Usp7 in Apc-truncated mice inhibits crypt hyperproliferation and intestinal tumor development. Loss of Usp7 prolongs the survival of the sporadic intestinal tumor model. Genetic deletion, but not pharmacological inhibition, of Usp7 in Apc+/- intestine induces colitis and enteritis. USP7 inhibitor treatment suppresses growth of patient-derived cancer organoids carrying APC truncations in vitro and in xenografts. Our findings provide direct evidence that USP7 inhibition may offer a safe and efficacious tumor-specific therapy for both sporadic and germline APC-mutated CRC.
Cui, Y;Wu, H;Liu, Z;Ma, T;Liang, W;Zeng, Q;Chen, D;Qin, Q;Huang, B;Wang, MH;Huang, X;He, Y;Kuang, Y;Sugimoto, S;Sato, T;Wang, L;
PMID: 36373877 | DOI: 10.1002/path.6031
Radiation enteritis (RE) is a prevalent complication of radiotherapy for pelvic malignant tumors, characterized by severe intestinal epithelial destruction and progressive submucosal fibrosis. However, little is known about the pathogenesis of this disease and so far, there is no specific targeted therapy. Here, we report that CXCL16 is up-regulated in the injured intestinal tissues of RE patients and in a mouse model. Genetic deletion of Cxcl16 mitigates fibrosis and promotes intestinal stem cell-mediated epithelial regeneration after radiation injury in mice. Mechanistically, CXCL16 functions on myofibroblasts through its receptor CXCR6 and activates JAK3/STAT3 signaling to promote fibrosis, and meanwhile to transcriptionally modulate the levels of BMP4 and HGF in myofibroblasts. Moreover, we find that CXCL16 and CXCR6 auto- and cross-regulate themselves in positive feedback loops. Treatment with CXCL16 neutralizing monoclonal antibody attenuates fibrosis and improves the epithelial repair in RE mouse model. Our findings emphasize the important role of CXCL16 in the progression of RE, and suggest that CXCL16 signaling could be a potential therapeutic target for RE. This article is protected by
Molecular nutrition & food research
May, S;Greenow, KR;Higgins, AT;Derrick, AV;Taylor, E;Pan, P;Konstantinou, M;Nixon, C;Wooley, TE;Sansom, OJ;Wang, LS;Parry, L;
PMID: 36045438 | DOI: 10.1002/mnfr.202200234
Black raspberries (BRBs) have colorectal cancer (CRC) chemo-preventative effects. As CRC originates from an intestinal stem cell (ISC) this study has investigated the impact of BRBs on normal and mutant ISCs.Mice with an inducible Apcfl mutation in either the ISC (Lgr5CreERT2 ) or intestinal crypt (AhCre/VillinCreERT2 ) are fed a control or 10% BRB-supplemented diet. This study uses immunohistochemistry, gene expression analysis, and organoid culture to evaluate the effect of BRBs on intestinal homeostasis. RNAscope is performed for ISC markers on CRC adjacent normal colonic tissue pre and post BRB intervention from patients. 10% BRB diet has no overt effect on murine intestinal homeostasis, despite a reduced stem cell number. Following Apc ISC deletion, BRB diet extends lifespan and reduces tumor area. In the AhCre model, BRB diet attenuates the "crypt-progenitor" phenotype and reduces ISC marker gene expression. In ex vivo culture BRBs reduce the self-renewal capacity of murine and human Apc deficient organoids. Finally, the study observes a reduction in ISC marker gene expression in adjacent normal crypts following introduction of BRBs to the human bowel.BRBs play a role in CRC chemoprevention by protectively regulating the ISC compartment and further supports the use of BRBs in CRC prevention.
Marinelli, S;Marrone, MC;Di Domenico, M;Marinelli, S;
PMID: 36222019 | DOI: 10.1002/glia.24281
Microglia, the innate immune cells of the central nervous system (CNS), execute their sentinel, housekeeping and defense functions through a panoply of genes, receptors and released cytokines, chemokines and neurotrophic factors. Moreover, microglia functions are closely linked to the constant communication with other cell types, among them neurons. Depending on the signaling pathway and type of stimuli involved, the outcome of microglia operation can be neuroprotective or neurodegenerative. Accordingly, microglia are increasingly becoming considered cellular targets for therapeutic intervention. Among signals controlling microglia activity, the endocannabinoid (EC) system has been shown to exert a neuroprotective role in many neurological diseases. Like neurons, microglia express functional EC receptors and can produce and degrade ECs. Interestingly, boosting EC signaling leads to an anti-inflammatory and neuroprotective microglia phenotype. Nonetheless, little evidence is available on the microglia-mediated therapeutic effects of EC compounds. This review focuses on the EC signals acting on the CNS microglia in physiological and pathological conditions, namely on the CB1R, CB2R and TRPV1-mediated regulation of microglia properties. It also provides new evidence, which strengthens the understanding of mechanisms underlying the control of microglia functions by ECs. Given the broad expression of the EC system in glial and neuronal cells, the resulting picture is the need for in vivo studies in transgenic mouse models to dissect the contribution of EC microglia signaling in the neuroprotective effects of EC-derived compounds.
The circadian clock gene, Bmal1, regulates intestinal stem cell signaling and represses tumor initiation
Cellular and molecular gastroenterology and hepatology
Stokes, K;Nunes, M;Trombley, C;Flôres, DEFL;Wu, G;Taleb, Z;Alkhateeb, A;Banskota, S;Harris, C;Love, OP;Khan, WI;Rueda, L;Hogenesch, JB;Karpowicz, P;
PMID: 34534703 | DOI: 10.1016/j.jcmgh.2021.08.001
Circadian rhythms are daily physiological oscillations driven by the circadian clock: a 24-hour transcriptional timekeeper that regulates hormones, inflammation, and metabolism. Circadian rhythms are known to be important for health, but whether their loss contributes to colorectal cancer is not known.We tested the non-redundant clock gene, Bmal1, in intestinal homeostasis and tumorigenesis, using the Apcmin model of colorectal cancer.Bmal1 mutant, epithelium-conditional Bmal1 mutant, and photoperiod-disrupted mice bearing the Apcmin allele were assessed for tumorigenesis. Tumors and normal non-transformed tissue were characterized. Intestinal organoids were assessed for circadian transcription rhythms by RNA-sequencing, and in vivo and organoid assays were used to test Bmal1-dependent proliferation and self-renewal.Loss of Bmal1 or circadian photoperiod increases tumor initiation. In the intestinal epithelium the clock regulates transcripts involved in regeneration and intestinal stem cell signaling. Tumors have no self-autonomous clock function and only weak clock function in vivo. Apcmin clock-disrupted tumors exhibit high Yap (Hippo signaling) activity but exhibit low Wnt activity. Intestinal organoid assays reveal that loss of Bmal1 increases self-renewal in a Yap-dependent manner.Bmal1 regulates intestinal stem cell pathways, including Hippo signaling, and the loss of circadian rhythms potentiates tumor initiation.
FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Schaaf, CR;Polkoff, KM;Carter, A;Stewart, AS;Sheahan, B;Freund, J;Ginzel, J;Snyder, JC;Roper, J;Piedrahita, JA;Gonzalez, LM;
PMID: 37159340 | DOI: 10.1096/fj.202300223R
Intestinal epithelial stem cells (ISCs) are responsible for intestinal epithelial barrier renewal; thereby, ISCs play a critical role in intestinal pathophysiology research. While transgenic ISC reporter mice are available, advanced translational studies lack a large animal model. This study validates ISC isolation in a new porcine Leucine Rich Repeat Containing G Protein-Coupled Receptor 5 (LGR5) reporter line and demonstrates the use of these pigs as a novel colorectal cancer (CRC) model. We applied histology, immunofluorescence, fluorescence-activated cell sorting, flow cytometry, gene expression quantification, and 3D organoid cultures to whole tissue and single cells from the duodenum, jejunum, ileum, and colon of LGR5-H2B-GFP and wild-type pigs. Ileum and colon LGR5-H2B-GFP, healthy human, and murine biopsies were compared by mRNA fluorescent in situ hybridization (FISH). To model CRC, adenomatous polyposis coli (APC) mutation was induced by CRISPR/Cas9 editing in porcine LGR5-H2B-GFP colonoids. Crypt-base, green fluorescent protein (GFP) expressing cells co-localized with ISC biomarkers. LGR5-H2B-GFPhi cells had significantly higher LGR5 expression (p < .01) and enteroid forming efficiency (p < .0001) compared with LGR5-H2B-GFPmed/lo/neg cells. Using FISH, similar LGR5, OLFM4, HOPX, LYZ, and SOX9 expression was identified between human and LGR5-H2B-GFP pig crypt-base cells. LGR5-H2B-GFP/APCnull colonoids had cystic growth in WNT/R-spondin-depleted media and significantly upregulated WNT/β-catenin target gene expression (p < .05). LGR5+ ISCs are reproducibly isolated in LGR5-H2B-GFP pigs and used to model CRC in an organoid platform. The known anatomical and physiologic similarities between pig and human, and those shown by crypt-base FISH, underscore the significance of this novel LGR5-H2B-GFP pig to translational ISC research.
Barbee, B;Gourley, S;
| DOI: 10.1016/j.addicn.2022.100012
Cocaine use disorder (CUD) is a significant public health issue that generates substantial personal, familial, and economic burdens. Still, there are no FDA-approved pharmacotherapies for CUD. Cocaine-dependent individuals report anxiety during withdrawal, and alleviation of anxiety and other negative affective states may be critical for maintaining drug abstinence. However, the neurobiological mechanisms underlying abstinence-related anxiety in humans or anxiety-like behavior in rodents are not fully understood. This review summarizes investigations regarding anxiety-like behavior in mice and rats undergoing cocaine abstinence, as assessed using four of the most common anxiety-related assays: the elevated plus (or its derivative, the elevated zero) maze, open field test, light-dark transition test, and defensive burying task. We first summarize available evidence that cocaine abstinence generates anxiety-like behavior that persists throughout protracted abstinence. Then, we examine investigations concerning neuropeptide, neurotransmitter, and neuromodulator systems in cocaine abstinence-induced anxiety-like behavior. Throughout, we discuss how differences in sex, rodent strain, cocaine dose and dosing strategy, and abstinence duration interact to generate anxiety-like behavior.
International Journal of Molecular Sciences
García-Gutiérrez, M;Navarrete, F;Gasparyan, A;Navarro, D;Morcuende, Á;Femenía, T;Manzanares, J;
| DOI: 10.3390/ijms23115908
Cumulative evidence has pointed out cannabinoid CB2 receptors (CB2r) as a potential therapeutic key target for treating alcohol use disorder (AUD). This review provides the most relevant results obtained from rodent and human studies, including an integrative section focused on the involvement of CB2r in the neurobiology of alcohol addiction. A literature search was conducted using the electronic databases Medline and Scopus for articles. The search strategy was as follows: “Receptor, Cannabinoid, CB2” AND “Alcohol-Related Disorders” AND “human/or patients”; “Receptor, Cannabinoid, CB2” AND “Alcohol” OR “Ethanol” AND “rodents/or mice/or rats”. Pharmacological approaches demonstrated that the activation or blockade of CB2r modulated different alcohol-addictive behaviors. Rodent models of alcoholism revealed significant alterations of CB2r in brain areas of the reward system. In addition, mice lacking CB2r (CB2KO) show increased alcohol consumption, motivation, and relapse alterations. It has been stressed that the potential neurobiological mechanisms underlying their behavioral effects involve critical elements of the alcohol reward system. Interestingly, recent postmortem studies showed CNR2 alterations in brain areas of alcoholic patients. Moreover, although the number of studies is limited, the results revealed an association between some genetic alterations of the CNR2 and an increased risk for developing AUD. This review provides evidence that CB2r may play a role in alcohol addiction. Clinical studies are necessary to figure out whether CB2r ligands may prove useful for the treatment of AUD in humans.
Jacob, JM;Di Carlo, SE;Stzepourginski, I;Lepelletier, A;Ndiaye, PD;Varet, H;Legendre, R;Kornobis, E;Benabid, A;Nigro, G;Peduto, L;
PMID: 35523143 | DOI: 10.1016/j.stem.2022.04.005
After birth, the intestine undergoes major changes to shift from an immature proliferative state to a functional intestinal barrier. By combining inducible lineage tracing and transcriptomics in mouse models, we identify a prodifferentiation PDGFRαHigh intestinal stromal lineage originating from postnatal LTβR+ perivascular stromal progenitors. The genetic blockage of this lineage increased the intestinal stem cell pool while decreasing epithelial and immune maturation at weaning age, leading to reduced postnatal growth and dysregulated repair responses. Ablating PDGFRα in the LTBR stromal lineage demonstrates that PDGFRα has a major impact on the lineage fate and function, inducing a transcriptomic switch from prostemness genes, such as Rspo3 and Grem1, to prodifferentiation factors, including BMPs, retinoic acid, and laminins, and on spatial organization within the crypt-villus and repair responses. Our results show that the PDGFRα-induced transcriptomic switch in intestinal stromal cells is required in the first weeks after birth to coordinate postnatal intestinal maturation and function.