85 research outputs found
Evaluation of the Reelin signaling in cancer stem cells isolated from tumor and peritumor tissue of glioblastoma
Reelin is a large secreted extracellular glycoprotein that plays a critical role in the regulation of neuronal migration during brain development. Reelin is thought to guide migrating neurons by interacting with cell surface receptors, very low density lipoprotein receptor (VLDLR), apolipoprotein E receptor 2 (ApoER2), and a3 b1integrin, inducing tyrosine phosphorylation of the intracellular adapter protein Disabled-1 (Dab-1) that instructs neurons to reach their correct laminar position in the cortex. Recent evidence supports a role of Reelin in the control of cell proliferation through the activation of mitogen protein kinase (ERK) pathway. We have previously shown, by immunohistochemistry and stereological analysis, the expression of Reelin in both Glioblastoma (GBM) and in peritumor tissue. Moreover, we reported the expression of Reelin in cancer stem cells isolated from both tumor (GCSC) and peritumor tissue (PCSC), suggesting that this protein might contribute to neurosphere formation. Here we investigated by both Real-Time Polymerase Chain Reaction (RT-PCR) and Western Blotting (WB) analysis the gene and protein expression of Reelin and its intracellular adapter Dab-1 in GCSC and PCSC derived from four different patients. Analysis of gene and protein expression indicates higher level of Reelin and DAB-1 in PCSC compared to GCSC. These data suggest a possible role for Reelin and Dab-1 in the control of cell migration and GBM invasiveness
Evaluation of the Reelin signaling in cancer stem cells isolated from tumor and peritumor tissue of glioblastoma
Reelin is a large secreted extracellular glycoprotein that plays a critical role in the regulation of neuronal migration during brain development. Reelin is thought to guide migrating neurons by interacting with cell surface receptors, very low density lipoprotein receptor (VLDLR), apolipoprotein E receptor 2 (ApoER2), and a3 b1integrin, inducing tyrosine phosphorylation of the intracellular adapter protein Disabled-1 (Dab-1) that instructs neurons to reach their correct laminar position in the cortex. Recent evidence supports a role of Reelin in the control of cell proliferation through the activation of mitogen protein kinase (ERK) pathway. We have previously shown, by immunohistochemistry and stereological analysis, the expression of Reelin in both Glioblastoma (GBM) and in peritumor tissue. Moreover, we reported the expression of Reelin in cancer stem cells isolated from both tumor (GCSC) and peritumor tissue (PCSC), suggesting that this protein might contribute to neurosphere formation. Here we investigated by both Real-Time Polymerase Chain Reaction (RT-PCR) and Western Blotting (WB) analysis the gene and protein expression of Reelin and its intracellular adapter Dab-1 in GCSC and PCSC derived from four different patients. Analysis of gene and protein expression indicates higher level of Reelin and DAB-1 in PCSC compared to GCSC. These data suggest a possible role for Reelin and Dab-1 in the control of cell migration and GBM invasiveness
Levetiracetam enhances the Temozolomide effect on glioblastoma stem cell proliferation
Glioblastoma Multiforme (GBM) is a highly aggressive brain tumor in which cancer cells with stem cell-like features, called Cancer Stem Cells (CSCs), were identified. CSCs show a high capacity to resist to standard therapies, finally leading to a poor prognosis. Thus, the development of efficient strategies targeting these cells are urgently needed. We have previously demonstrated the presence of two CSC populations in GBM, one derived from the GBM area called enhanced lesion (GCSC) and the other one from the brain area adjacent to the tumor margin (PCSC), that greatly differ in their growth properties and tumor-initiating ability. Tumor recurrence occurs in tissue neighboring GBM suggesting a growing relevance for this area in translational research. To date the most effective chemotherapies to treat GBM are alkylating agents such as temozolomide (TMZ). Epigenetic mechanisms are increasingly recognized as a major factor contributing to pathogenesis of cancer including glioblastoma. Histone deacetylase (HDAC) inhibitors can interfere with TMZ activity by modulating methylguanine methyltransferase (MGMT) expression, resulting in increased TMZ efficacy. Levetiracetam (LEV), an antiepileptic drug, is known to modulate the transcription of HDAC, ultimately silencing MGMT.Since TMZ is the chemotherapeutic agent most widely used in newly diagnosed adult glioblastoma patients, we evaluated its effects on the proliferation rate of both GCSC and PCSC deriving from five patients, in comparison with the effects of other drugs such as etoposide, irinotecan and car-boplatin. Our results demonstrated that TMZ was the less efficient agent, hence we verified the pos-sibility to increase the effect of TMZ by combining it with LEV. Here we show that LEV signifi-cantly enhances the inhibitory effect of TMZ on the proliferation of the GCSC deriving from four patients and of the PCSC deriving from two patients. This effect seems to be mediated by HDAC6 since its expression is up-regulated in the TMZ resistant cells and correlates with MGMT expression. Taken together our results suggest that GCSC and PCSC differ in their ability to respond to the combined chemotherapeutic treatment we used and that the manipulation of HDAC6 expression might be a potential strategy for treating glioblastoma and overcoming resistance to TMZ
Centro recreacional nautico para impulsar la recuperación de la Franja Costera de la Caleta la Cruz, Tumbes – 2023
Esta investigación trata sobre la propuesta urbana arquitectónica de un centro
recreacional náutico para impulsar la recuperación de la franja costera de la caleta
La Cruz, Tumbes, para lo cual realiza el estudio de la realidad problemática y
antecedentes de estudio a nivel mundial, latinoamericano y nacional, con
fundamentación en las teorías del turismo náutico, la reconversión urbana y la
pesca artesanal sostenible. Su objetivo principal es el diseño urbano arquitectónico
y sus específicos son la comprensión de las alteraciones, efectos y la generación
de un modelo de análisis de la problemática identificada. Es investigación
cualitativa, critica y propositiva, con resultados basados en entrevistas y 6
identificas, procesadas en 3 análisis estructurales, llegándose a determinar 26
deficiencias de diversas tipologías. La propuesta es la generación de 9 estrategias
específicas de diseño, con 7 acciones de aplicación proyectual, componentes para
la propuesta urbana arquitectónica
B cell depletion in diffuse progressive systemic sclerosis: safety, skin score modification and IL-6 modulation in an up to thirty-six months follow-up open-label trial
INTRODUCTION: An over-expression of CD19 has been shown in B cells of systemic sclerosis (SSc) and B cells are thought to contribute to the induction of skin fibrosis in the tight skin mouse model. The aim was to define the outcome on safety and the change in skin score after rituximab therapy in SSc patients and to correlate the clinical characteristics with the levels of interleukin (IL)-6 and with the immune cell infiltrate detected by immunohistochemistry.
METHODS: Nine patients with SSc with mean age 40.9 +/- 11.1 years were treated with anti-CD20, 1 g at time 0 and after 14 days. Skin biopsy was performed at baseline and during the follow-up. B-cell activating factor (BAFF) and IL-6 levels were also determined at the follow-up times.
RESULTS: After 6 months patients presented a median decrease of the skin score of 43.3% (range 21.1-64.0%), and a decrease in disease activity index and disease severity index. IL-6 levels decreased permanently during the follow up. After treatment, a complete depletion of peripheral blood B cells was observed in all but 2 patients. Only 3 patients presented CD20 positive cells in the biopsy of the involved skin at baseline.
CONCLUSIONS: Anti-CD20 treatment has been well tolerated and SSc patients experienced an improvement of the skin score and of clinical symptoms. The clear fall in IL-6 levels could contribute to the skin fibrosis improvement, while the presence of B cells in the skin seems to be irrelevant with respect to the outcome after B cell depletion
Epithelium-stroma reciprocal influence in breast cancer. Focus on plasma membrane features related to cell migratory/invasive ability
Interactions occurring between malignant cells and stromal microenvironment greatly influence progression of breast cancer. In a previous study, we co-cultured mammary cancer cells exhibiting different degrees of metastatic potential (MDA-MB- 231>MCF-7) with fibroblasts isolated from breast healthy skin (normal fibroblasts, NFs) or breast tumor stroma (cancer-associated fibroblasts, CAFs). In this system, we demonstrated the influence exerted in particular by CAFs on malignant cells, leading to the acquisition of a more aggressive/invasive phenotype (i.e. reduced adhesion, epithelial-mesenchymal transition, enhanced plasma membrane fluidity and migration velocity/directness). In the present study, we evaluated the reciprocal effect of breast tumor cells and fibroblasts in co-culture on the expression of the main enzyme regulating the fatty acids membrane composition, Stearoyl-CoA desaturase 1 (SCD1). Abnormally high levels of SCD1 have been reported in different cancers and transformed cells and the enzyme has been recently raised to the role of key regulator of cell growth, programmed cell death and carcinogenesis. In our experience, Western blot analysis demonstrated a strong increase in SCD1 expression in both MCF-7 and MDA-MB-231 cells, resulting from their interaction with CAFs and, at a lesser extent, with NFs. High levels of SCD1 were also observed in both NFs and CAFs when co-cultured with MCF-7 cells. MDA-MB-231 cells more slightly up-regulated the enzyme expression in NFs or even induced a certain inhibition in CAFs. The fibroblast-triggered up-regulation of SCD1 in cancer cells could reasonably be considered the molecular event underlying the increase of membrane fluidity, previously observed in tumor cells co-cultured with NFs and, notably, with CAFs. This change might downstream promote the previously described increase in tumor cell motility
Expression of angiogenesis related factors in glioblastoma and peritumor tissue
Glioblastoma (GBM) is a lethal brain glial tumor characterized by extensive angiogenesis that is mostly triggered by tumor hypoxia. We previous reported that in GBM and in peritumor areas, endothelial cells expressed CD105, which probably marks newly formed vessels with a quite similar morphology. In this study, with the aim of better understanding the involvement of angiogenesis in tumor progression, we analyzed, by immunohistochemistry, the expression of Hypoxia-inducible factor (HIF) 1α and 2α, VEGF and its receptors (VEGFR-1 and -2) in GBM and in peritumor tissue. Twenty two patients were enrolled in this study. Tissue specimens were derived from enhanced lesion (first area) and white matter at a distance ≤1 mm from the tumor edge (second area). Immunoreactivity for all markers was detected not only in the tumor but also in the peritumor tissue and it was present in neoplastic cells, in endothelium and in apparently normal glial cells. HIF1α and 2α expression was mainly confined in the nuclei. VEGF, localized in the cytoplasm, showed diffuse expression with an intense staining in GBM. VEGFR-1 and 2 immupositivity was localized especially to the cell membrane and also to the cytoplasm, as expected. All molecule staining was evident in a heterogeneous manner and there was no significant difference in the expression marker levels between the first and second area also in relation to the presence or absence of tumor cells in the second area. No significant correlation was found between the above molecule expression and survival time. In conclusion, we demonstrated that HIF1α, HIF2α, VEGF and VEGFR-1 and -2 are present in peritumor area, probably reflecting perturbations of oxygenation emanating from the tumor microenvironment. Since, unfortunately, the response to anti-VEGF therapy is transient and the majority of patients eventually relapse, the gain of a deeper knowledge of the above molecule role, in the peritumor tissue, may lead to consider them as the target for new treatment regimens to counteract angiogenesis. Supported by FIRB “Accordi di Programma” 201
Multifaceted Functional Role of Semaphorins in Glioblastoma
Glioblastoma (GBM) is the most malignant tumor type affecting the adult central nervous system. Despite advances in therapy, the prognosis for patients with GBM remains poor, with a median survival of about 15 months. To date, few treatment options are available and recent trials based on the molecular targeting of some of the GBM hallmark pathways (e.g., angiogenesis) have not produced any significant improvement in overall survival. The urgent need to develop more efficacious targeted therapies has led to a better molecular characterization of GBM, revealing an emerging role of semaphorins in GBM progression. Semphorins are a wide group of membrane-bound and secreted proteins, originally identified as axon guidance cues, signaling through their receptors, neuropilins, and plexins. A number of semaphorin signals involved in the control of axonal growth and navigation during development have been found to furthermore participate in crosstalk with different dysfunctional GBM pathways, controlling tumor cell proliferation, migration, and invasion, as well as tumor angiogenesis or immune response. In this review, we summarize the regulatory activities mediated by semaphorins and their receptors on the oncogenic pathways implicated in GBM growth and invasive/metastatic progression
Palmitoylethanolamide counteracts autistic-like behaviours in BTBR T+tf/J mice: Contribution of central and peripheral mechanisms
Abstract Autism spectrum disorders (ASD) are a group of heterogeneous neurodevelopmental conditions characterized by impaired social interaction, and repetitive stereotyped behaviours. Interestingly, functional and inflammatory gastrointestinal diseases are often reported as a comorbidity in ASDs, indicating gut-brain axis as a novel emerging approach. Recently, a central role for peroxisome-proliferator activated receptor (PPAR)-α has been addressed in neurological functions, associated with the behaviour. Among endogenous lipids, palmitoylethanolamide (PEA), a PPAR-α agonist, has been extensively studied for its anti-inflammatory effects both at central and peripheral level. Based on this background, the aim of this study was to investigate the pharmacological effects of PEA on autistic-like behaviour of BTBR T+tf/J mice and to shed light on the contributing mechanisms. Our results showed that PEA reverted the altered behavioural phenotype of BTBR mice, and this effect was contingent to PPAR-α activation. Moreover, PEA was able to restore hippocampal BDNF signalling pathway, and improve mitochondrial dysfunction, both pathological aspects, known to be consistently associated with ASDs. Furthermore, PEA reduced the overall inflammatory state of BTBR mice, reducing the expression of pro-inflammatory cytokines at hippocampal, serum, and colonic level. The analysis of gut permeability and the expression of colonic tight junctions showed a reduction of leaky gut in PEA-treated BTBR mice. This finding together with PEA effect on gut microbiota composition suggests an involvement of microbiota-gut-brain axis. In conclusion, our results demonstrated a therapeutic potential of PEA in limiting ASD symptoms, through its pleiotropic mechanism of action, supporting neuroprotection, anti-inflammatory effects, and the modulation of gut-brain axis
Breast cancer cells and fibroblasts in co-culture: reciprocal influences on cell adhesion, membrane fluidity and migration
The growing role of the reciprocal interaction between epithelial and stromal cells in the development and progression of breast cancer has been recognized. In particular, the migratory/invasive behaviour of tumor cells seems to be strongly influenced by their dialogue with neighbouring stromal cells. To verify if this cross-talk may affect some molecular and functional aspects of the cell biology correlated with the metastasizing vocation of the tumor cells (i.e. adhesion molecule expression, membrane fluidity, migration), we co-cultured estrogen receptor (ER)-positive, poorly invasive and low metastasizing (MCF-7) or ER-negative, highly invasive and metastatic (MDA-MB-231) breast cancer cells with fibroblasts isolated from breast healthy skin (normal fibroblasts, NFs) or from breast tumor stroma (cancer associated fibroblasts, CAFs) in monolayer or in a three-dimensional system (nodules). We previously reported the ability of NFs and CAFs to respectively induce or inhibit the epithelial adhesion molecule, E-cadherin, expression in MCF-7 cells. In the present study, the expression of the mesenchymal adhesion protein N-cadherin (N-cad) was investigated by confocal immunofluorescence microscopy on frozen nodule sections. An increase in N-cad levels was observed in CAFs, but not in NFs, as a result of the interaction with both kinds of epithelial cancer cells. CAFs, in turn, promoted an increase in N-cad level of MDA-MB-231 cells and induced its expression in MCF-7 cells, originally negative for N-cad. Two-photon microscopy imaging of cells labeled with Laurdan, a membrane fluorescent probe, was used to investigate fluidity changes in plasma membranes of all the cell types in monolayer cultures. Tumor cell/fibroblast interaction enhanced fluidity of cancer cell membrane while tumor cells generally promoted an increase in fibroblast membrane packing density. Cell tracking by confocal microscopy demonstrated that the interaction of mammary cancer cells with NFs or CAFs determined a definite increment in tumor cell migration velocity, even with a marked enhancement of the migration directionality induced by CAFs. Our results demonstrate a reciprocal influence of mammary cancer and stromal cells on various adhesiveness/invasiveness features. In particular, an overall pro-tumoral/-invasive effect of CAFs on both well- and poorly differentiated mammary cancer cells was exteriorized by reduction of cell adhesion, induction of membrane fluidity, and migration velocity and directionality, along with a promotion of epithelial-mesenchymal transition
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