RESUMO
Glioblastoma multiforme (GBM) is the most aggressive form of brain cancer with marginal life expectancy. Based on the assumption that GBM cells gain functions not necessarily involved in the cancerous process, patient-derived glioblastoma cells (GCs) were screened to identify cellular processes amenable for development of targeted treatments. The quinine-derivative NSC13316 reliably and selectively compromised viability. Synthetic chemical expansion reveals delicate structure-activity relationship and analogs with increased potency, termed Vacquinols. Vacquinols stimulate death by membrane ruffling, cell rounding, massive macropinocytic vacuole accumulation, ATP depletion, and cytoplasmic membrane rupture of GCs. The MAP kinase MKK4, identified by a shRNA screen, represents a critical signaling node. Vacquinol-1 displays excellent in vivo pharmacokinetics and brain exposure, attenuates disease progression, and prolongs survival in a GBM animal model. These results identify a vulnerability to massive vacuolization that can be targeted by small molecules and point to the possible exploitation of this process in the design of anticancer therapies.
Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Piperidinas/farmacologia , Quinolinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Xenoenxertos , Humanos , Hidroxiquinolinas/farmacologia , MAP Quinase Quinase 4/metabolismo , Camundongos , Transplante de Neoplasias , Pinocitose/efeitos dos fármacos , Vacúolos/metabolismo , Peixe-ZebraRESUMO
Current knowledge of cancer genomics remains biased against noncoding mutations. To systematically search for regulatory noncoding mutations, we assessed mutations in conserved positions in the genome under the assumption that these are more likely to be functional than mutations in positions with low conservation. To this end, we use whole-genome sequencing data from the International Cancer Genome Consortium and combined it with evolutionary constraint inferred from 240 mammals, to identify genes enriched in noncoding constraint mutations (NCCMs), mutations likely to be regulatory in nature. We compare medulloblastoma (MB), which is malignant, to pilocytic astrocytoma (PA), a primarily benign tumor, and find highly different NCCM frequencies between the two, in agreement with the fact that malignant cancers tend to have more mutations. In PA, a high NCCM frequency only affects the BRAF locus, which is the most commonly mutated gene in PA. In contrast, in MB, >500 genes have high levels of NCCMs. Intriguingly, several loci with NCCMs in MB are associated with different ages of onset, such as the HOXB cluster in young MB patients. In adult patients, NCCMs occurred in, e.g., the WASF-2/AHDC1/FGR locus. One of these NCCMs led to increased expression of the SRC kinase FGR and augmented responsiveness of MB cells to dasatinib, a SRC kinase inhibitor. Our analysis thus points to different molecular pathways in different patient groups. These newly identified putative candidate driver mutations may aid in patient stratification in MB and could be valuable for future selection of personalized treatment options.
Assuntos
Neoplasias Cerebelares , Meduloblastoma , Adulto , Animais , Humanos , Meduloblastoma/patologia , Mutação , Genoma , Neoplasias Cerebelares/genética , Quinases da Família src/genética , Mamíferos/genética , Proteínas de Ligação a DNA/genéticaRESUMO
A deleterious effect of elevated levels of vitamin A on bone health has been reported in clinical studies. Mechanistic studies in rodents have shown that numbers of periosteal osteoclasts are increased, while endocortical osteoclasts are simultaneously decreased by vitamin A treatment. The present study investigated the in vitro and in vivo effect of all-trans retinoic acid (ATRA), the active metabolite of vitamin A, on periosteal osteoclast progenitors. Mouse calvarial bone cells were cultured in media containing ATRA, with or without the osteoclastogenic cytokine receptor activator of nuclear factor kappa B-ligand (RANKL), on plastic dishes or bone discs. Whereas ATRA did not stimulate osteoclast formation alone, the compound robustly potentiated the formation of RANKL-induced bone resorbing osteoclasts. This effect was due to stimulation by ATRA (half-maximal stimulation â¼3 nM) on the numbers of macrophages/osteoclast progenitors in the bone cell cultures, as assessed by mRNA and protein expression of several macrophage and osteoclast progenitor cell markers, such as macrophage colony-stimulating factor receptor, receptor activator of nuclear factor kappa B, F4/80, and CD11b, as well as by flow cytometry (FACS) analysis of CD11b+/F480+/Gr1- cells. The stimulation of macrophage numbers in the periosteal cell cultures was not mediated by increased macrophage colony-stimulating factor or interleukin-34. In contrast, ATRA did not enhance macrophages in bone marrow cell cultures. Importantly, ATRA treatment upregulated the mRNA expression of several macrophage-related genes in the periosteum of tibia in adult mice. These observations demonstrate a novel mechanism by which vitamin A enhances osteoclast formation specifically on periosteal surfaces.
Assuntos
Macrófagos , Osteoclastos , Periósteo , Ligante RANK , Vitamina A , Animais , Camundongos , Osteoclastos/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/citologia , Periósteo/metabolismo , Periósteo/citologia , Ligante RANK/metabolismo , Vitamina A/farmacologia , Vitamina A/metabolismo , Células-Tronco/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia , Células Cultivadas , Tretinoína/farmacologia , Osteogênese/efeitos dos fármacos , Camundongos Endogâmicos C57BL , MasculinoRESUMO
Discoveries in the field of genomics have revealed that non-coding genomic regions are not merely "junk DNA", but rather comprise critical elements involved in gene expression. These gene regulatory elements (GREs) include enhancers, insulators, silencers, and gene promoters. Notably, new evidence shows how mutations within these regions substantially influence gene expression programs, especially in the context of cancer. Advances in high-throughput sequencing technologies have accelerated the identification of somatic and germline single nucleotide mutations in non-coding genomic regions. This review provides an overview of somatic and germline non-coding single nucleotide alterations affecting transcription factor binding sites in GREs, specifically involved in cancer biology. It also summarizes the technologies available for exploring GREs and the challenges associated with studying and characterizing non-coding single nucleotide mutations. Understanding the role of GRE alterations in cancer is essential for improving diagnostic and prognostic capabilities in the precision medicine era, leading to enhanced patient-centered clinical outcomes.
Assuntos
Mutação , Neoplasias , Humanos , Neoplasias/genética , Sequências Reguladoras de Ácido Nucleico/genética , Genoma Humano , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação Neoplásica da Expressão GênicaRESUMO
Therapeutic strategies directed at the tumor surfaceome (TS), including checkpoint inhibitor blocking antibodies, antibody drug conjugates (ADCs), and chimeric antigen receptor T (CAR-T) cells, provide a new armament to fight cancer. However, a remaining bottleneck is the lack of strategies to comprehensively interrogate patient tumors for potential TS targets. Here, we have developed a platform (tumor surfaceome mapping [TS-MAP]) integrated with a newly curated TS classifier (SURFME) that allows profiling of primary 3D cultures and intact patient glioma tumors with preserved tissue architecture. Moreover, TS-MAP specifically identifies proteins capable of endocytosis as tractable targets for ADCs and other modalities requiring toxic payload internalization. In high-grade gliomas that remain among the most aggressive forms of cancer, we show that cellular spatial organization (2D vs. 3D) fundamentally transforms the surfaceome and endocytome (e.g., integrins, proteoglycans, semaphorins, and cancer stem cell markers) with general implications for target screening approaches, as exemplified by an ADC targeting EGFR. The TS-MAP platform was further applied to profile the surfaceome and endocytome landscape in a cohort of freshly resected gliomas. We found a highly diverse TS repertoire between patient tumors, not directly associated with grade and histology, which highlights the need for individualized approaches. Our data provide additional layers of understanding fundamental to the future development of immunotherapy strategies, as well as procedures for proteomics-based target identification and selection. The TS-MAP platform should be widely applicable in efforts aiming at a better understanding of how to harness the TS for personalized immunotherapy.
Assuntos
Neoplasias Encefálicas/patologia , Endocitose , Glioma/patologia , Linhagem Celular Tumoral , Humanos , Proteínas de Neoplasias/metabolismo , Proteômica/métodosRESUMO
Osteoporosis is an age-dependent serious skeletal disease that leads to great suffering for the patient and high social costs, especially as the global population reaches higher age. Decreasing estrogen levels after menopause result in a substantial bone loss and increased fracture risk, whereas estrogen treatment improves bone mass in women. RSPO3, a secreted protein that modulates WNT signaling, increases trabecular bone mass and strength in the vertebrae of mice, and is associated with trabecular density and risk of distal forearm fractures in humans. The aim of the present study was to determine if RSPO3 is involved in the bone-sparing effect of estrogens. We first observed that estradiol (E2) treatment increases RSPO3 expression in bone of ovariectomized (OVX) mice, supporting a possible role of RSPO3 in the bone-sparing effect of estrogens. As RSPO3 is mainly expressed by osteoblasts in the bone, we used a mouse model devoid of osteoblast-derived RSPO3 (Runx2-creRspo3flox/flox mice) to determine if RSPO3 is required for the bone-sparing effect of E2 in OVX mice. We confirmed that osteoblast-specific RSPO3 inactivation results in a substantial reduction in trabecular bone mass and strength in the vertebrae. However, E2 increased vertebral trabecular bone mass and strength similarly in mice devoid of osteoblast-derived RSPO3 and control mice. Unexpectedly, osteoblast-derived RSPO3 was needed for the full estrogenic response on cortical bone thickness. In conclusion, although osteoblast-derived RSPO3 is a crucial regulator of vertebral trabecular bone, it is required for a full estrogenic effect on cortical, but not trabecular, bone in OVX mice. Thus, estradiol and RSPO3 regulate vertebral trabecular bone mass independent of each other.NEW & NOTEWORTHY Osteoblast-derived RSPO3 is known to be a crucial regulator of vertebral trabecular bone. Our new findings show that RSPO3 and estrogen regulate trabecular bone independent of each other, but that RSPO3 is necessary for a complete estrogenic effect on cortical bone.
Assuntos
Fraturas Ósseas , Osteoporose , Animais , Densidade Óssea , Osso Esponjoso/metabolismo , Estradiol/farmacologia , Estrogênios/farmacologia , Feminino , Humanos , Camundongos , Osteoporose/genética , Osteoporose/metabolismo , Ovariectomia , Trombospondinas/genética , Trombospondinas/farmacologiaRESUMO
The gut microbiome has the capacity to regulate bone mass. The aim of this study was to develop a nutritional synbiotic dietary assemblage at an optimal dose to maintain bone mass in ovariectomized (Ovx) mice. We performed genomic analyses and in vitro experiments in a large collection of bacterial and fungal strains (>4,000) derived from fresh fruit and vegetables to identify candidates with the synergistic capacity to produce bone-protective short-chain fatty acids (SCFA) and vitamin K2. The candidate SBD111-A, composed of Lactiplantibacillus plantarum, Levilactobacillus brevis, Leuconostoc mesenteroides, Pseudomonas fluorescens, and Pichia kudriavzevii together with prebiotic dietary fibers, produced high levels of SCFA in vitro and protected against Ovx-induced trabecular bone loss in a dose-dependent manner in mice. Metagenomic sequencing revealed that SBD111-A changed the taxonomic composition and enriched specific pathways for synthesis of bone-protective SCFA, vitamin K2, and branched-chain amino acids in the gut microbiome.NEW & NOTEWORTHY We performed genomic analyses and in vitro experiments in a collection of bacterial and fungal strains. We identified a combination (SBD111-A) that produced high levels of SCFA in vitro and protected against ovariectomy-induced bone loss in a dose-dependent manner in mice. Metagenomic sequencing revealed that SBD111-A changed the taxonomic composition and function of the gut microbiome and enriched pathways for synthesis of bone-protective SCFA, vitamin K2, and branched-chain amino acids.
Assuntos
Osso Esponjoso , Simbióticos , Aminoácidos de Cadeia Ramificada , Animais , Bactérias , Ácidos Graxos Voláteis , Feminino , Humanos , Camundongos , Ovariectomia , Vitamina K 2RESUMO
Osteoporosis is a common skeletal disease, with increased risk of fractures. Currently available osteoporosis treatments reduce the risk of vertebral fractures, mainly dependent on trabecular bone, whereas the effect on nonvertebral fractures, mainly dependent on cortical bone, is less pronounced. WNT signaling is a crucial regulator of bone homeostasis, and the activity of WNTs is inhibited by NOTUM, a secreted WNT lipase. We previously demonstrated that conditional inactivation of NOTUM in all osteoblast lineage cells increases the cortical but not the trabecular bone mass. The aim of the present study was to determine if NOTUM increasing cortical bone is derived from osteoblast precursors/early osteoblasts or from osteocytes/late osteoblasts. First, we demonstrated Notum mRNA expression in Dmp1-expressing osteocytes and late osteoblasts in cortical bone using in situ hybridization. We then developed a mouse model with inactivation of NOTUM in Dmp1-expressing osteocytes and late osteoblasts (Dmp1-creNotumflox/flox mice). We observed that the Dmp1-creNotumflox/flox mice displayed a substantial reduction of Notum mRNA in cortical bone, resulting in increased cortical bone mass and decreased cortical porosity in femur but no change in trabecular bone volume fraction in femur or in the lumbar vertebrae L5 in Dmp1-creNotumflox/flox mice as compared with control mice. In conclusion, osteocytes and late osteoblasts are the principal source of NOTUM in cortical bone, and NOTUM derived from osteocytes/late osteoblasts reduces cortical bone mass. These findings demonstrate that inhibition of osteocyte/late osteoblast-derived NOTUM might be an interesting pharmacological target to increase cortical bone mass and reduce nonvertebral fracture risk.NEW & NOTEWORTHY NOTUM produced by osteoblasts is known to regulate cortical bone mass. Our new findings show that NOTUM specifically derived by DMP1-expressing osteocytes and late osteoblasts regulates cortical bone mass and not trabecular bone mass.
Assuntos
Densidade Óssea/genética , Esterases/fisiologia , Osteoblastos/metabolismo , Osteócitos/metabolismo , Osteoporose/genética , Animais , Remodelação Óssea/genética , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Osso Cortical/fisiologia , Esterases/genética , Esterases/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Osteoblastos/fisiologia , Osteócitos/fisiologia , Osteogênese/genética , Osteoporose/metabolismoRESUMO
Mutation of arginine 264 in ERα has been shown to abrogate rapid membrane ERα-mediated endothelial effects. Our novel finding that mutation of R264 is dispensable for ERα-mediated skeletal effects supports the concept that R264 determines tissue specificity of ERα. Estrogen protects against bone loss but is not a suitable treatment due to adverse effects in other tissues. Therefore, increased knowledge regarding estrogen signaling in estrogen-responsive tissues is warranted to aid the development of bone-specific estrogen treatments. Estrogen receptor-α (ERα), the main mediator of estrogenic effects in bone, is widely subjected to posttranslational modifications (PTMs). In vitro studies have shown that methylation at site R260 in the human ERα affects receptor localization and intracellular signaling. The corresponding amino acid R264 in murine ERα has been shown to have a functional role in endothelium in vivo, although the methylation of R264 in the murine gene is yet to be empirically demonstrated. The aim of this study was to investigate whether R264 in ERα is involved in the regulation of the skeleton in vivo. Dual-energy X-ray absorptiometry (DEXA) analysis at 3, 6, 9, and 12 mo of age showed no differences in total body areal bone mineral density (BMD) between R264A and wild type (WT) in either female or male mice. Furthermore, analyses using computed tomography (CT) demonstrated that trabecular bone mass in tibia and vertebra and cortical thickness in tibia were similar between R264A and WT mice. In addition, R264A females displayed a normal estrogen treatment response in trabecular bone mass as well as in cortical thickness. Furthermore, uterus, thymus, and adipose tissue responded similarly in R264A and WT female mice after estrogen treatment. In conclusion, our novel finding that mutation of R264 in ERα does not affect the regulation of the skeleton, together with the known role of R264 for ERα-mediated endothelial effects, supports the concept that R264 determines tissue specificity of ERα.NEW & NOTEWORTHY Mutation of arginine 264 in ERα has been shown to abrogate rapid membrane ERα-mediated endothelial effects. Our novel finding that mutation of R264 is dispensable for ERα-mediated skeletal effects supports the concept that R264 determines tissue specificity of ERα.
Assuntos
Arginina/genética , Arginina/fisiologia , Osso e Ossos/fisiologia , Receptor alfa de Estrogênio/genética , Absorciometria de Fóton , Envelhecimento/fisiologia , Animais , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Endotélio/metabolismo , Estrogênios/farmacologia , Feminino , Metilação , Camundongos , Tamanho do Órgão/genética , Ovariectomia , Coluna Vertebral/química , Coluna Vertebral/metabolismo , Tíbia/química , Tíbia/metabolismo , Tomografia Computadorizada por Raios XRESUMO
Objectives: To investigate the association between precarious employment and health in a sample of non-standard employees in Stockholm County, Sweden, by addressing three specific research questions: is the degree of precarious employment (low, moderate, high) associated with self-rated. . . (a) general health, (b) mental health, (c) musculoskeletal pain? Methods: Web-based respondent-driven sampling was used to recruit a sample of 415 employees in Stockholm, Sweden, during 2016-2017. Questionnaire data were collected on employment conditions (the Swedish version of the employment precariousness scale (EPRES-Se)), general health, mental health and musculoskeletal pain. EPRES-Se scores were categorised as low, moderate or high. Generalised linear models with Poisson distribution, log link functions and robust variances were applied for calculating crude and adjusted prevalence ratios (PR; aPR) with 95% confidence intervals (CIs) for all outcomes. Results: The prevalence ratios of poor self-rated general and mental health increased with increased degree of precariousness, as indicated by estimates of moderate precarious employment (a2PRModerate 1.44 (CI 0.98-2.11); a2PRModerate 1.13 (CI 0.82-1.62)), and high precarious employment (a2PRHigh 1.78 (CI 1.21-2.62); a2PRHigh 1.69 (CI 1.25-2.28)), albeit only significantly so for high precarious employment. Conclusions: This is the first study in Sweden reporting on the association between precarious employment, as measured with a multidimensional scale, and multiple health outcomes. The results add to the evidence of an association between precarious employment and self-rated poor general and mental health. Larger, representative studies with longitudinal designs using the EPRES-Se are called for in order to strengthen these results and the already existing evidence of the harm of precarious employment.
Assuntos
Emprego/estatística & dados numéricos , Nível de Saúde , Saúde Mental/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Suécia , Adulto JovemRESUMO
This study investigated whether parental caregiving burden changed during adjunct multi-family therapy of adolescent anorexia nervosa and eating disorders not otherwise specified (EDNOS) and whether caregiver burden at baseline and changes in caregiver burden during treatment were associated with treatment outcome.Twenty-four females, 13 to 16 years old, and their parents, participated in the study. Caregiver burden was measured with the Eating Disorders Symptom Impact Scale, by mothers (n = 23) and fathers (n = 22). Treatment outcome was measured by adolescent body mass index, level of global functioning and self-rated eating disorder symptoms by the Eating Disorders Examination Questionnaire 4.0.All patient outcomes improved and overall caregiver burden decreased significantly during treatment. When broken down in aspects of caregiver burden the decrease in parental perceived isolation, was found to be associated with improvement of BMI and Children's Global Assessment Scale. When analyzing fathers and mothers separately, we found that maternal feelings of guilt and paternal perceived burden of dysregulated behaviors at base-line were correlated to treatment outcome. Future studies are needed to clarify the role of caregiver burden as a potential mediator of treatment results.
Assuntos
Anorexia Nervosa , Adolescente , Anorexia Nervosa/terapia , Sobrecarga do Cuidador , Criança , Terapia Familiar , Feminino , Humanos , Masculino , Mães , PaisRESUMO
Probiotic bacteria can protect from ovariectomy (ovx)-induced bone loss in mice. Akkermansia muciniphila is considered to have probiotic potential due to its beneficial effect on obesity and insulin resistance. The purpose of the present study was to determine if treatment with pasteurized Akkermansia muciniphila (pAkk) could prevent ovx-induced bone loss. Mice were treated with vehicle or pAkk for 4 wk, starting 3 days before ovx or sham surgery. Treatment with pAkk reduced fat mass accumulation confirming earlier findings. However, treatment with pAkk decreased trabecular and cortical bone mass in femur and vertebra of gonadal intact mice and did not protect from ovx-induced bone loss. Treatment with pAkk increased serum parathyroid hormone (PTH) levels and increased expression of the calcium transporter Trpv5 in kidney suggesting increased reabsorption of calcium in the kidneys. Serum amyloid A 3 (SAA3) can suppress bone formation and mediate the effects of PTH on bone resorption and bone loss in mice and treatment with pAkk increased serum levels of SAA3 and gene expression of Saa3 in colon. Moreover, regulatory T cells can be protective of bone and pAkk-treated mice had decreased number of regulatory T cells in mesenteric lymph nodes and bone marrow. In conclusion, treatment with pAkk protected from ovx-induced fat mass gain but not from bone loss and reduced bone mass in gonadal intact mice. Our findings with pAkk differ from some probiotics that have been shown to protect bone mass, demonstrating that not all prebiotic and probiotic factors have the same effect on bone.
Assuntos
Tecido Adiposo/crescimento & desenvolvimento , Microbioma Gastrointestinal/fisiologia , Osteoporose/metabolismo , Probióticos/farmacologia , Verrucomicrobia/metabolismo , Tecido Adiposo/metabolismo , Akkermansia , Animais , Canais de Cálcio/metabolismo , Colo/efeitos dos fármacos , Colo/microbiologia , Feminino , Fêmur/efeitos dos fármacos , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , Hormônio Paratireóideo/metabolismo , Pasteurização , Proteína Amiloide A Sérica/metabolismo , Coluna Vertebral/efeitos dos fármacos , Linfócitos T Reguladores , Canais de Cátion TRPV/metabolismoRESUMO
Epidemiological studies have shown that high bone mineral density (BMD) is associated with an increased risk of osteoarthritis (OA), but the causality of this relationship remains unclear. Both bone mass and OA have been associated with the WNT signaling pathway in genetic studies, there is thus an interest in studying molecular partners of the WNT signaling pathway and OA. Female mice overexpressing WNT16 in osteoblasts (Obl-Wnt16 mice) have an increased bone mass. We aimed to evaluate if the high bone mass in Obl-Wnt16 mice leads to a more severe experimental OA development than in WT control mice. We induced experimental OA in female Obl-Wnt16 and WT control mice by destabilizing the medial meniscus (DMM). The Obl-Wnt16 mice displayed thicker medial and lateral subchondral bone plates as well as increased subchondral trabecular bone volume/tissue volume (BV/TV) but un-altered thickness of articular cartilage compared to WT mice. After DMM surgery, there was no difference in OA severity in the articular cartilage in the knee joint between the Obl-Wnt16 and WT mice. Both the Obl-Wnt16 and WT mice developed osteophytes in the DMM-operated tibia to a similar extent. We conclude that although the Obl-Wnt16 female mice have a high subchondral bone mass due to increased WNT signaling, they do not exhibit a more severe OA phenotype than their WT controls. This demonstrates that high bone mass does not result in an increased risk of OA per se.
Assuntos
Densidade Óssea , Osteoartrite/metabolismo , Osteoblastos/metabolismo , Proteínas Wnt/metabolismo , Animais , Cartilagem Articular , Feminino , Camundongos , TíbiaRESUMO
Osteoporosis is a common skeletal disease, affecting millions of individuals worldwide. Currently used osteoporosis treatments substantially reduce vertebral fracture risk, whereas nonvertebral fracture risk, mainly caused by reduced cortical bone mass, has only moderately been improved by the osteoporosis drugs used, defining an unmet medical need. Because several wingless-type MMTV integration site family members (WNTs) and modulators of WNT activity are major regulators of bone mass, we hypothesized that NOTUM, a secreted WNT lipase, might modulate bone mass via an inhibition of WNT activity. To characterize the possible role of endogenous NOTUM as a physiologic modulator of bone mass, we developed global, cell-specific, and inducible Notum-inactivated mouse models. Notum expression was high in the cortical bone in mice, and conditional Notum inactivation revealed that osteoblast lineage cells are the principal source of NOTUM in the cortical bone. Osteoblast lineage-specific Notum inactivation increased cortical bone thickness via an increased periosteal circumference. Inducible Notum inactivation in adult mice increased cortical bone thickness as a result of increased periosteal bone formation, and silencing of Notum expression in cultured osteoblasts enhanced osteoblast differentiation. Large-scale human genetic analyses identified genetic variants mapping to the NOTUM locus that are strongly associated with bone mineral density (BMD) as estimated with quantitative ultrasound in the heel. Thus, osteoblast-derived NOTUM is an essential local physiologic regulator of cortical bone mass via effects on periosteal bone formation in adult mice, and genetic variants in the NOTUM locus are associated with BMD variation in adult humans. Therapies targeting osteoblast-derived NOTUM may prevent nonvertebral fractures.-Movérare-Skrtic, S., Nilsson, K. H., Henning, P., Funck-Brentano, T., Nethander, M., Rivadeneira, F., Coletto Nunes, G., Koskela, A., Tuukkanen, J., Tuckermann, J., Perret, C., Souza, P. P. C., Lerner, U. H., Ohlsson, C. Osteoblast-derived NOTUM reduces cortical bone mass in mice and the NOTUM locus is associated with bone mineral density in humans.
Assuntos
Densidade Óssea/genética , Osso Cortical/metabolismo , Osso Cortical/fisiologia , Esterases/metabolismo , Osteoblastos/metabolismo , Animais , Densidade Óssea/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Esterases/genética , Feminino , Fraturas Ósseas/metabolismo , Fraturas Ósseas/fisiopatologia , Variação Genética/genética , Humanos , Masculino , Camundongos , Osteogênese/genética , Osteogênese/fisiologia , Osteoporose/metabolismo , Osteoporose/fisiopatologia , Proteínas Wnt/metabolismoRESUMO
Brain tumors are aggressive and devastating diseases. The most common type of brain tumor, glioblastoma (GBM), is incurable and has one of the worst five-year survival rates of all human cancers. GBMs are invasive and infiltrate healthy brain tissue, which is one main reason they remain fatal despite resection, since cells that have already migrated away lead to rapid regrowth of the tumor. Curative therapy for medulloblastoma (MB), the most common pediatric brain tumor, has improved, but the outcome is still poor for many patients, and treatment causes long-term complications. Recent advances in the classification of pediatric brain tumors reveal distinct subgroups, allowing more targeted therapy for the most aggressive forms, and sparing children with less malignant tumors the side-effects of massive treatment. Heparan sulfate proteoglycans (HSPGs), main components of the neurogenic niche, interact specifically with a large number of physiologically important molecules and vital roles for HS biosynthesis and degradation in neural stem cell differentiation have been presented. HSPGs are composed of a core protein with attached highly charged, sulfated disaccharide chains. The major enzyme that degrades HS is heparanase (HPSE), an important regulator of extracellular matrix (ECM) remodeling which has been suggested to promote the growth and invasion of other types of tumors. This is of clinical interest because GBM are highly invasive and children with metastatic MB at the time of diagnosis exhibit a worse outcome. Here we review the involvement of HS and HPSE in development of the nervous system and some of its most malignant brain tumors, glioblastoma and medulloblastoma.
Assuntos
Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Glucuronidase/metabolismo , Heparitina Sulfato/metabolismo , Glioblastoma/enzimologia , Glioblastoma/patologia , Proteoglicanas de Heparan Sulfato , Humanos , Meduloblastoma/enzimologia , Meduloblastoma/patologiaRESUMO
Heparanase is an endo-ß-d-glucuronidase that cleaves heparan sulfate (HS) side chains of heparan sulfate proteoglycans. Compelling evidence tie heparanase levels with all steps of tumor formation including tumor initiation, growth, metastasis and chemo-resistance, likely involving augmentation of signaling pathways and gene transcription. In order to reveal the molecular mechanism(s) underlying the protumorigenic properties of heparanase, we established an inducible (Tet-on) system in U87 human glioma cells and applied gene array methodology in order to identify genes associated with heparanase induction. We found that CD24, a mucin-like cell adhesion protein, is consistently upregulated by heparanase and by heparanase splice variant devoid of enzymatic activity, whereas heparanase gene silencing was associated with decreased CD24 expression. This finding was further substantiated by a similar pattern of heparanase and CD24 immunostaining in glioma patients (Pearson's correlation; R = 0.66, p = 0.00001). Noteworthy, overexpression of CD24 stimulated glioma cell migration, invasion, colony formation in soft agar and tumor growth in mice suggesting that CD24 functions promote tumor growth. Likewise, anti-CD24 neutralizing monoclonal antibody attenuated glioma tumor growth, and a similar inhibition was observed in mice treated with a neutralizing mAb directed against L1 cell adhesion molecule (L1CAM), a ligand for CD24. Importantly, significant shorter patient survival was found in heparanase-high/CD24-high tumors vs. heparanase-high/CD24-low tumors for both high-grade and low-grade glioma (p = 0.02). Our results thus uncover a novel heparanase-CD24-L1CAM axis that plays a significant role in glioma tumorigenesis.
Assuntos
Neoplasias Encefálicas/patologia , Antígeno CD24/metabolismo , Glioma/patologia , Glucuronidase/metabolismo , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Feminino , Glioma/metabolismo , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Transdução de SinaisRESUMO
Globally, lake fish communities are being subjected to a range of scale-dependent anthropogenic pressures, from climate change to eutrophication, and from overexploitation to species introductions. As a consequence, the composition of these communities is being reshuffled, in most cases leading to a surge in taxonomic similarity at the regional scale termed homogenization. The drivers of homogenization remain unclear, which may be a reflection of interactions between various environmental changes. In this study, we investigate two potential drivers of the recent changes in the composition of freshwater fish communities: recreational fishing and climate change. Our results, derived from 524 lakes of Ontario, Canada sampled in two periods (1965-1982 and 2008-2012), demonstrate that the main contributors to homogenization are the dispersal of gamefish species, most of which are large predators. Alternative explanations relating to lake habitat (e.g., area, phosphorus) or variations in climate have limited explanatory power. Our analysis suggests that human-assisted migration is the primary driver of the observed compositional shifts, homogenizing freshwater fish community among Ontario lakes and generating food webs dominated by gamefish species.
Assuntos
Mudança Climática , Lagos , Animais , Ecossistema , Eutrofização , Peixes , Humanos , OntárioRESUMO
OBJECTIVES: The aim of this study was to assess the psychometric properties of a Swedish version of the Hayling test (HT-S) and its clinical utility in a group of patients with different frontotemporal dementia (FTD) syndromes. Early diagnosis of FTD is a challenge and requires a broad arsenal of assessment methods, neuropsychological tests not the least. The Hayling test assesses executive functions including initiation, efficiency and response inhibition. METHODS: Seventy-six healthy controls were included as well as patients with the behavioral variant FTD (bvFTD; n = 17), semantic dementia (SD, n = 6), and progressive supranuclear palsy (n = 12). The Color Word Interference Test was administered to examine the construct validity. RESULTS: Age showed a correlation with better performances in younger participants whereas the importance of sex and education were less evident. The split half reliability and internal consistency were equal to, or better, than reported for the original version. The interrater reliability was excellent. The construct validity was supported, nevertheless indicating partly different processes behind the performances of the two tests. The FTD group performed significantly worse than healthy controls on efficiency and response inhibition and there were also significant differences in performances between the syndromes despite small samples. CONCLUSIONS: The psychometric properties and clinical utility of the Swedish version are satisfactory for measuring efficiency and response inhibition with results indicating dissimilar profiles in the performances in the different syndromes. These results need to be corroborated in larger samples. (JINS, 2019, 25, 195-203).
Assuntos
Função Executiva/fisiologia , Demência Frontotemporal/diagnóstico , Inibição Psicológica , Testes Neuropsicológicos/normas , Paralisia Supranuclear Progressiva/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Demência Frontotemporal/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Paralisia Supranuclear Progressiva/fisiopatologia , SuéciaRESUMO
Gliomas are the most common form of malignant primary brain tumors in humans and second most common in dogs, occurring with similar frequencies in both species. Dogs are valuable spontaneous models of human complex diseases including cancers and may provide insight into disease susceptibility and oncogenesis. Several brachycephalic breeds such as Boxer, Bulldog and Boston Terrier have an elevated risk of developing glioma, but others, including Pug and Pekingese, are not at higher risk. To identify glioma-associated genetic susceptibility factors, an across-breed genome-wide association study (GWAS) was performed on 39 dog glioma cases and 141 controls from 25 dog breeds, identifying a genome-wide significant locus on canine chromosome (CFA) 26 (p = 2.8 x 10-8). Targeted re-sequencing of the 3.4 Mb candidate region was performed, followed by genotyping of the 56 SNVs that best fit the association pattern between the re-sequenced cases and controls. We identified three candidate genes that were highly associated with glioma susceptibility: CAMKK2, P2RX7 and DENR. CAMKK2 showed reduced expression in both canine and human brain tumors, and a non-synonymous variant in P2RX7, previously demonstrated to have a 50% decrease in receptor function, was also associated with disease. Thus, one or more of these genes appear to affect glioma susceptibility.