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A complex interplay between mRNA translation and cellular respiration has been recently unveiled, but its regulation in humans is poorly characterized in either health or disease. Cancer cells radically reshape both biosynthetic and bioenergetic pathways to sustain their aberrant growth rates. In this regard, we have shown that the molecular chaperone TRAP1 not only regulates the activity of respiratory complexes, behaving alternatively as an oncogene or a tumor suppressor, but also plays a concomitant moonlighting function in mRNA translation regulation. Herein, we identify the molecular mechanisms involved, showing that TRAP1 (1) binds both mitochondrial and cytosolic ribosomes, as well as translation elongation factors; (2) slows down translation elongation rate; and (3) favors localized translation in the proximity of mitochondria. We also provide evidence that TRAP1 is coexpressed in human tissues with the mitochondrial translational machinery, which is responsible for the synthesis of respiratory complex proteins. Altogether, our results show an unprecedented level of complexity in the regulation of cancer cell metabolism, strongly suggesting the existence of a tight feedback loop between protein synthesis and energy metabolism, based on the demonstration that a single molecular chaperone plays a role in both mitochondrial and cytosolic translation, as well as in mitochondrial respiration.
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Mitocondrias , Proteínas Mitocondriales , Chaperonas Moleculares , Neoplasias , Biosíntesis de Proteínas , Humanos , Proteínas HSP90 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Biosíntesis de Proteínas/genética , Biosíntesis de Proteínas/fisiología , Ribosomas/genética , Ribosomas/metabolismo , Extensión de la Cadena Peptídica de Translación/genética , Extensión de la Cadena Peptídica de Translación/fisiología , Mitocondrias/genética , Mitocondrias/metabolismoRESUMEN
FOXP3-expressing regulatory T-cells (Tregs), which suppress aberrant immune response against self-antigens, also suppress anti-tumor immune response. It has been shown that there is an increased proportion of Tregs in several different human malignancies, although the actual mechanism remains unclear. The research aims to explore the relationship between the number of Tregs and a predict prognosis in particular hematological diseases as monoclonal gammopathies of uncertain significance (MGUS). Tregs were evaluated by means of flow cytometry (CD4+CD25high/+ CD127low/-) in whole peripheral blood of 56 patients with MGUS to predict progression to overt multiple myeloma (MM). In two groups of patients, MGUS versus MGUS evolved to MM, we found a significative difference for the number of white blood cells, but not in terms of clinical and laboratory features evaluated at diagnosis. The study demonstrated the absence of a prognostic relevance of Tregs in MGUS. Nevertheless, their role in these disorders is still to be defined.
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Gammopatía Monoclonal de Relevancia Indeterminada/diagnóstico , Gammopatía Monoclonal de Relevancia Indeterminada/inmunología , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Células , Progresión de la Enfermedad , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Gammopatía Monoclonal de Relevancia Indeterminada/patología , Mieloma Múltiple/patología , PronósticoRESUMEN
Syndesmos (SDOS) is a functionally poorly characterized protein that directly interacts with p53 binding protein 1 (53BP1) and regulates its recruitment to chromatin. We show here that SDOS interacts with another important cancer-linked protein, the chaperone TRAP1, associates with actively translating polyribosomes and represses translation. Moreover, we demonstrate that SDOS directly binds RNA in living cells. Combining individual gene expression profiling, nucleotide crosslinking and immunoprecipitation (iCLIP), and ribosome profiling, we discover several crucial pathways regulated post-transcriptionally by SDOS. Among them, we identify a small subset of mRNAs responsible for the biogenesis of primary cilium that have been linked to developmental and degenerative diseases, known as ciliopathies, and cancer. We discover that SDOS binds and regulates the translation of several of these mRNAs, controlling cilia development.
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Cilios/genética , Proteínas de Unión al ARN/fisiología , Cilios/metabolismo , Ciliopatías/genética , Células HCT116 , Proteínas HSP90 de Choque Térmico/metabolismo , Células HeLa , Humanos , Neoplasias/genética , Polirribosomas/metabolismo , Unión Proteica/genética , Biosíntesis de Proteínas/genética , Dominios y Motivos de Interacción de Proteínas/genética , Estructura Terciaria de Proteína , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/genéticaRESUMEN
Despite the significant recent advances in clinical practice, gastric cancer (GC) represents a leading cause of cancer-related deaths in the world. In fact, occurrence of chemo-resistance still remains a daunting hindrance to effectiveness of the current approach to GC therapy. There is accumulating evidence that a plethora of cellular and molecular factors is implicated in drug-induced phenotypical switching of GC cells. Among them, epithelial-mesenchymal transition (EMT), autophagy, drug detoxification, DNA damage response and drug target alterations, have been reported as major determinants. Intriguingly, resistant GC phenotype may be the result of GC cell-induced tumor microenvironment (TME) remodeling, which is currently emerging as a key player in promoting drug resistance and overcoming cytotoxic effects of drugs. In this review, we discuss the possible mechanisms of drug resistance and their involvement in determining current GC therapies failure.
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Autofagia/genética , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Neovascularización Patológica/genética , Neoplasias Gástricas/genética , Microambiente Tumoral/genética , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Antineoplásicos/uso terapéutico , Autofagia/efectos de los fármacos , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Supervivencia Celular/genética , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Transición Epitelial-Mesenquimal/genética , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/patología , Helicobacter pylori/crecimiento & desarrollo , Helicobacter pylori/patogenicidad , Humanos , Hipoxia/tratamiento farmacológico , Hipoxia/genética , Hipoxia/metabolismo , Hipoxia/patología , Inactivación Metabólica/genética , MicroARNs/genética , MicroARNs/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Microambiente Tumoral/efectos de los fármacosRESUMEN
We study the role of contingent convertible bonds (CoCos) in a complex network of interconnected banks. By studying the system's phase transitions, we reveal that the structure of the interbank network is of fundamental importance for the effectiveness of CoCos as a financial stability enhancing mechanism. Our results show that, under some network structures, the presence of CoCos can increase (and not reduce) financial fragility, because of the occurring of unneeded triggers and consequential suboptimal conversions that damage CoCos investors. We also demonstrate that, in the presence of a moderate financial shock, lightly interconnected financial networks are more robust than highly interconnected networks. This makes them a potentially optimal choice for both CoCos issuers and buyers.
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BACKGROUND: Redox signaling and energy metabolism are known to be involved in controlling the balance between self-renewal and proliferation/differentiation of stem cells. In this study we investigated metabolic and redox changes occurring during in vitro human dental pulp stem cells (hDPSCs) osteoblastic (OB) differentiation and tested on them the impact of the reactive oxygen species (ROS) signaling. METHODS: hDPSCs were isolated from dental pulp and subjected to alkaline phosphatase and alizarin red staining, q-RT-PCR, and western blotting analysis of differentiation markers to assess achievement of osteogenic/odontogenic differentiation. Moreover, a combination of metabolic flux analysis and confocal cyto-imaging was used to profile the metabolic phenotype and to evaluate the redox tone of hDPSCs. RESULTS: In differentiating hDPSCs we observed the down-regulation of the mitochondrial respiratory chain complexes expression since the early phase of the process, confirmed by metabolic flux analysis, and a reduction of the basal intracellular peroxide level in its later phase. In addition, dampened glycolysis was observed, thereby indicating a lower energy-generating phenotype in differentiating hDPSCs. Treatment with the ROS scavenger Trolox, applied in the early-middle phases of the process, markedly delayed OB differentiation of hDPSCs assessed as ALP activity, Runx2 expression, mineralization capacity, expression of stemness and osteoblast marker genes (Nanog, Lin28, Dspp, Ocn) and activation of ERK1/2. In addition, the antioxidant partly prevented the inhibitory effect on cell metabolism observed following osteogenic induction. CONCLUSIONS: Altogether these results provided evidence that redox signaling, likely mediated by peroxide species, influenced the stepwise osteogenic expansion/differentiation of hDPSCs and contributed to shape its accompanying metabolic phenotype changes thus improving their efficiency in bone regeneration and repair.
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Pulpa Dental , Osteogénesis , Humanos , Especies Reactivas de Oxígeno , Regeneración Ósea , Metabolismo Energético , Oxidación-Reducción , Niacinamida , Fosfatasa Alcalina/genéticaRESUMEN
BACKGROUND: Breast lesions of uncertain malignant potential, also known as B3 lesions, represent a heterogeneous group of tumors with variable malignancy risk. Surgical excision should be considered depending on clinical, radiological and histological features, family history and following informed consent. The aim of the present paper is to evaluate the positive predictive value (PPV) of diagnosis of malignancy in surgically excised B3 lesions in order to identify possible predictive upgrade criteria. We mainly focused on disclosing the concordance rate between tissue biopsy and final surgical pathology and correlation between radiology and pathology. METHODS: Between January 2018 and December 2021, 83 patients undergoing ultrasound guided tru-cut needle biopsy or VABB with a B3 diagnosis and surgical excision following multidisciplinary discussion were retrospectively reviewed in our Breast Unit. RESULTS: Out of a total of 83 cases with a B3 diagnosis before surgery, atypical ductal hyperplasia accounted for 29/83 cases(34.93%) and the most part of patients presented nodular lesions (n = 34/83, 40.96%). Among the 15 cases of malignancy detected after surgery, micro calcifications were registered in 53.3% of patients on mammography (n = 8/15). CONCLUSION: We assessed the correlation between radiological and pathological criteria in order to guide risk stratification and ensure adequate patient management. Correspondence between histological diagnosis, imaging and type of diagnostic biopsy were evaluated. No statistically significant predictors were identified for the parameters assessed in our study. KEY WORDS: B3 Breast Lesions, Lesions of Uncertains Malignant Potential, Mammografic Distortion, Screen Detected Breast Lesion.
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Neoplasias de la Mama , Neoplasias , Humanos , Femenino , Estudios Retrospectivos , Mama/patología , Mamografía , Biopsia con Aguja/métodos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugíaRESUMEN
Allogeneic hematopoietic stem cell transplantation (AHSCT) is a life-saving treatment for selected hematological malignancies. So far, it remains unclear whether transplanted hematopoietic stem/progenitor cells (HSPCs) undergo epigenetic changes upon engraftment in recipient bone marrow (BM) after AHSCT and whether these changes might be useful in the transplant diagnostics. The purpose of this study was to characterize the whole genome methylation profile of HSPCs following AHSCT. Moreover, the relationship between the observed methylation signature and patient outcome was analyzed. Mobilized peripheral blood (mPB)-HSPCs from seven donors and BM-HSPCs longitudinally collected from transplanted patients with hematological malignancies up to one year from AHSCT (a total of twenty-eight samples) were analyzed using DNA methylation based-arrays. The obtained data showed that DNA methylation of mPB-HSPCs differs between young and adult donors and changes following HSPC engraftment in the BM of recipient patients. Looking at methylation in promoter regions, at 30 days post-AHSCT, BM-HSPCs showed a higher number of differentially methylated genes (DMGs) compared to those of mPB-HSPCs, with a prevalent hyper-methylation. These changes were maintained during all the analyzed time points, and methylation became like the donors after one year from transplant. Functional analysis of these DMGs showed an enrichment in cell adhesion, differentiation and cytokine (interleukin-2, -5 and -7) production and signaling pathways. Of note, DNA methylation analysis allowed to identify a potential "cancer/graft methylation signature" of transplant failure. It was evident in the latest available post-transplant BM-HSPC sample (at 160 days) and surprisingly already in early phase (at 30 days) in patients whose transplant was doomed to fail. Overall, the analysis of HSPC methylation profile could offer useful prognostic information to potentially assess engraftment success and predict graft failure in AHSCT.
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Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Adulto , Humanos , Médula Ósea , Metilación de ADN , Células Madre Hematopoyéticas/metabolismo , Neoplasias Hematológicas/terapia , Células de la Médula ÓseaRESUMEN
A complex interplay between mRNA translation and cellular respiration has been recently unveiled, but its regulation in humans is poorly characterized in either health or disease. Cancer cells radically reshape both biosynthetic and bioenergetic pathways to sustain their aberrant growth rates. In this regard, we have shown that the molecular chaperone TRAP1 not only regulates the activity of respiratory complexes, behaving alternatively as an oncogene or a tumor suppressor, but also plays a concomitant moonlighting function in mRNA translation regulation. Herein we identify the molecular mechanisms involved, demonstrating that TRAP1: i) binds both mitochondrial and cytosolic ribosomes as well as translation elongation factors, ii) slows down translation elongation rate, and iii) favors localized translation in the proximity of mitochondria. We also provide evidence that TRAP1 is coexpressed in human tissues with the mitochondrial translational machinery, which is responsible for the synthesis of respiratory complex proteins. Altogether, our results show an unprecedented level of complexity in the regulation of cancer cell metabolism, strongly suggesting the existence of a tight feedback loop between protein synthesis and energy metabolism, based on the demonstration that a single molecular chaperone plays a role in both mitochondrial and cytosolic translation, as well as in mitochondrial respiration.
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Gastric cancer, the second most common cause of death worldwide, is characterized by poor prognosis and low responsiveness to chemotherapy. Indeed, multidrug resistance, based mainly on cellular and molecular factors, remains one of the most limiting factors of the current approach to gastric cancer (GC) therapy. We employed a comprehensive gene expression analysis through data mining of publicly available databases to assess the role of the signal transducer and activator of transcription 3 (STAT3) in gastric cancer drug efficiency. It has been proposed that gastric cancer cells are less sensitive to these drugs because they develop resistance to these agents through activating alternative signalling pathways responsible for overcoming pharmacological inhibition. Our study evaluated the hypothesis that activating STAT3 signalling in response to cisplatin reduces the reaction to the drug. Consistent with this hypothesis, inhibition of interleukin 6 (IL-6)/STAT3 in combination therapy with cisplatin prevented both STAT3 activation and more lethality than induction by a single agent. The data suggest that the IL-6/STAT3 axis block associated with cisplatin treatment may represent a strategy to overcome resistance.
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BACKGROUND: B-cell chronic lymphocytic leukemia (B-CLL) is characterized by the expansion of CD5+ malignant B lymphocytes. Recent discoveries have shown that double-negative T (DNT) cells, double-positive T (DPT) cells, and natural killer T (NKT)-cells may be involved in tumor surveillance. METHODS: A detailed immunophenotypic analysis of the peripheral blood T-cell compartment of 50 patients with B-CLL (classified in three prognostic groups) and 38 healthy donors (as controls) matched for age was performed. The samples were analyzed by flow cytometry using a stain-lyse-no wash technique and a comprehensive six-color antibody panels. RESULTS: Our data confirmed a reduction in percentage values and an increase in absolute values of T lymphocytes in patients with B-CLL, as already reported. In particular, DNT, DPT, and NKT-like percentages were significantly lower than in the controls, except for NKT-like in the low-risk prognostic group. Moreover, a significant rise in the absolute counts of DNT cells in each prognostic group and in the low-risk prognostic group of NKT-like cells was found. A significant correlation of the absolute values of NKT-like cells in the intermediate-risk prognostic group versus B cells was observed. Furthermore, we analyzed whether the increase in T cells was related to the subpopulations of interest. Only DNT cells were positively correlated with the increase in CD3+ T lymphocytes, regardless of the stage of the disease, supporting the hypothesis that this T-cell subset plays a key role in the immune T response in B-CLL. CONCLUSION: These early results supported that DNT, DPT, and NKT-like subsets may be related to disease progression and should encourage further studies aimed at identifying the potential immune surveillance role of these minority T subpopulations.
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Leucemia Linfocítica Crónica de Células B , Células T Asesinas Naturales , Humanos , Subgrupos de Linfocitos T , Linfocitos B/patología , Células T Asesinas Naturales/patología , Células Asesinas Naturales , Citometría de FlujoRESUMEN
Acute myeloid leukemia (AML) is an aggressive and heterogeneous clonal disorder of hematopoietic stem/progenitor cells (HSPCs). It is not well known how leukemia cells alter hematopoiesis promoting tumor growth and leukemic niche formation. In this study, we investigated how AML deregulates the hematopoietic process of HSPCs through the release of extracellular vesicles (EVs). First, we found that AML cells released a heterogeneous population of EVs containing microRNAs involved in AML pathogenesis. Notably, AML-EVs were able to influence the fate of HSPCs modifying their transcriptome. In fact, gene expression profile of AML-EV-treated HSPCs identified 923 down- and 630 up-regulated genes involved in hematopoiesis/differentiation, inflammatory cytokine production and cell movement. Indeed, most of the down-regulated genes are targeted by AML-EV-derived miRNAs. Furthermore, we demonstrated that AML-EVs were able to affect HSPC phenotype, modifying several biological functions, such as inhibiting cell differentiation and clonogenicity, activating inflammatory cytokine production and compromising cell movement. Indeed, a redistribution of HSPC populations was observed in AML-EV treated cells with a significant increase in the frequency of common myeloid progenitors and a reduction in granulocyte-macrophage progenitors and megakaryocyte-erythroid progenitors. This effect was accompanied by a reduction in HSPC colony formation. AML-EV treatment of HSPCs increased the levels of CCL3, IL-1B and CSF2 cytokines, involved in the inflammatory process and in cell movement, and decreased CXCR4 expression associated with a reduction of SDF-1 mediated-migration. In conclusion, this study demonstrates the existence of a powerful communication between AML cells and HSPCs, mediated by EVs, which suppresses normal hematopoiesis and potentially contributes to create a leukemic niche favorable to neoplastic development.
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Gastric cancer (GC) molecular heterogeneity represents a major determinant for clinical outcomes, and although new molecular classifications have been introduced, they are not easy to translate from bench to bedside. We explored the data from GC public databases by performing differential gene expression analysis (DEGs) and gene network reconstruction to identify master regulators (MRs), as well as a gene set analysis (GSA) to reveal their biological features. Moreover, we evaluated the association of MRs with clinicopathological parameters. According to the GSA, the Diffuse group was characterized by an epithelial-mesenchymal transition (EMT) and inflammatory response, while the Intestinal group was associated with a cell cycle and drug resistance pathways. In particular, the regulons of Diffuse MRs, such as Vgll3 and Ciita, overlapped with the EMT and interferon-gamma response, while the regulons Top2a and Foxm1 were shared with the cell cycle pathways in the Intestinal group. We also found a strict association between MR activity and several clinicopathological features, such as survival. Our approach led to the identification of genes and pathways differentially regulated in the Intestinal and Diffuse GC histotypes, highlighting biologically interesting MRs and subnetworks associated with clinical features and prognosis, suggesting putative actionable candidates.
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Insulin-like growth factor binding protein 6 (IGFBP6) is a secreted protein with a controversial role in human malignancies, being downregulated in most types of human cancer, but upregulated in selected tumors. Ovarian cancer (OC) is a human malignancy characterized by IGFBP6 downregulation; however, the significance of its low expression during ovarian carcinogenesis is still poorly understood. In the present study, IGFBP6 expression and activation of its associated signaling pathway were evaluated in two matched OC cell lines derived from a high-grade serous OC before and after platinum resistance (PEA1 and PEA2 cells, respectively). A whole genome gene expression analysis was comparatively performed in both cell lines upon IGFBP6 stimulation using Illumina technology. IGFBP6 gene expression data from human OC cases were obtained from public datasets. Gene expression data from public datasets confirmed the downregulation of IGFBP6 in primary and metastatic OC tissues compared with in normal ovarian tissues. The comparative analysis of platinum-sensitive (PEA1) and platinum-resistant (PEA2) cell lines showed quantitative and qualitative differences in the activation of IGFBP6 signaling. Notably, IGFBP6 enhanced ERK1/2 phosphorylation only in PEA1 cells, and induced more evident and significant gene expression reprogramming in PEA1 cells compared with in PEA2 cells. Furthermore, the analysis of selected genes modulated by IGFBP6 (i.e., FOS, JUN, TNF, IL6, IL8 and EGR1) exhibited an inverse regulation in PEA1 versus PEA2 cells. In addition, selected hallmarks (TNFA_signaling_via_NFKB, TGF_beta_signaling, P53_pathway) and IL-6 signaling were positively regulated in PEA1 cells, whereas they were inhibited in PEA2 cells in response to IGFBP6. These data suggested that dysregulation of IGFBP6 signaling may serve a role in the progression of OC, and is likely associated with the development of platinum resistance.
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Radiotherapy (RT) is an important therapeutic option in patients with localized prostate cancer (PC). Unfortunately, radiation treatment causes a decrease in peripheral lymphocytes and, consequently, influences the patients' immune status. Our aim was to study changes in peripheral blood immune cell subpopulations after RT and during 6 months' follow-up in 2 groups of PC patients irradiated with different techniques and dose fractions with curative intent. We also investigated the presence of correlation between immune cell modulation and genitourinary or gastrointestinal toxicity. We enrolled 44 patients treated with curative RT (RapidArc/hypofractionation regimen or 3D conformal/conventional fractionation) for localized PC. Total white blood cell (WBC), absolute lymphocyte counts (ALCs), and peripheral immune cell subpopulations were analyzed at baseline, at the end of RT, and 3 and 6 months after the end of RT. WBC and ALC greatly decreased at the end of RT with a trend to recover at 6 months' follow-up in the hypofractionation group but not in the conventional one. Furthermore, B, total T, T CD4+, T CD8+, and NK cell values dropped significantly in both groups at the end of RT, with a minor decrease detectable in the hypofractionation group for B, total T, and T CD4+ lymphocytes with respect to the other technique/fractionation group. Double-negative T (DNT), double-positive T (DPT), and NKT cells significantly decreased at the end of RT with a slight tendency to recover values during follow-up, particularly in the hypofractionation group. No correlation with genitourinary or gastrointestinal toxicity was found. In this study, we showed, for the first time, the effects of RapidArc/moderate hypofractionation RT on immune cell subsets in patients treated for localized PC. Due to the growing interest in minority T-cell subpopulations for immunotherapy, we also reported longitudinal monitoring of the effects of RT on DNT, DPT, and NKT, which was never studied before. Our preliminary data highlight the importance of considering the effects of different RT techniques/fractionation regimens on peripheral immune cells, in the era of RT and immunotherapy combination.
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Gastric cancer (GC) is characterized by poor efficacy and modest clinical impact of current therapies, in which apoptosis evasion is relevant. Intracellular calcium homeostasis dysregulation is associated with apoptosis escaping, and aberrant expression of calcium regulator genes could promote GC drug resistance. Since we previously found a prognostic value for TRPV2 calcium channel expression in GC, we aimed to characterize the role of TRPV2 in cisplatin resistance. Using the TCGA-STAD dataset, we performed a differential gene expression analysis between GC samples in upper and lower tertiles of TRPV2 expression, and then through a gene set analysis, we highlighted the enriched ontology and canonical pathways. We used qRT-PCR to assess TRPV2 expression in three GC cell lines and flow cytometry to evaluate cisplatin-induced cell death rates. Calcium green-1-AM assay was used to estimate differences in intracellular Ca2+ concentrations after inhibition of TRPV2. We engineered AGS cell line to overexpress TRPV2 and used confocal microscopy to quantify its overexpression and localization and flow cytometry to evaluate their sensitivity to cisplatin. Consistent with our hypothesis, among enriched gene sets, we found a significant number of those involved in the regulation of apoptosis. Subsequently, we found an inverse correlation between TRPV2 expression and sensitivity to cisplatin in GC cell lines. Moreover, we demonstrated that inhibition of TRPV2 activity by tranilast blocks the efflux of Ca2+ ions and, in combination with cisplatin, induced a significant increase of apoptotic cells (p = 0.004). We also demonstrated that TRPV2 exogenous expression confers a drug-resistant phenotype, and that tranilast is able to revert this phenotype, restoring cisplatin sensitivity. Our findings consistently suggested that TRPV2 could be a potential target for overcoming cisplatin resistance by promoting apoptosis. Notably, our data are a prerequisite for the potential reposition of tranilast to the treatment of GC patients and anticipate the in vivo evaluation.
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The peculiar aspect that emerges from the study of Orchidaceae is the presence of various molecules, which are particularly interesting for pharmaceutical chemistry due to their wide range of biological resources. The aim of our study was to investigate the properties of two dihydrophenanthrenes, isolated, for the first time, from Himantoglossum robertianum (Loisel.) P. Delforge (Orchidaceae) bulbs and roots. Chemical and spectroscopic study of the bulbs and roots of Himantoglossumrobertianum (Loisel.) P. Delforge resulted in the isolation of two known dihydrophenanthrenes-loroglossol and hircinol-never isolated from this plant species. The structures were evaluated based on 1H-NMR, 13C-NMR, and two-dimensional spectra, and by comparison with the literature. These two molecules have been tested for their possible antioxidant, antimicrobial, antiproliferative, and proapoptotic activities. In particular, it has been shown that these molecules cause an increase in the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) in polymorphonuclear leukocytes (PMN); show antimicrobial activity against Escherichia coli and Staphylococcus aureus, and have anti-proliferative effects on gastric cancer cell lines, inducing apoptosis effects. Therefore, these two molecules could be considered promising candidates for pharmaceutical and nutraceutical preparations.
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Epigenetics is involved in tumor progression and drug resistance in human colorectal carcinoma (CRC). This study addressed the hypothesis that the DNA methylation profiling may predict the clinical behavior of metastatic CRCs (mCRCs). The global methylation profile of two human mCRC subgroups with significantly different outcome was analyzed and compared with gene expression and methylation data from The Cancer Genome Atlas COlon ADenocarcinoma (TCGA COAD) and the NCBI GENE expression Omnibus repository (GEO) GSE48684 mCRCs datasets to identify a prognostic signature of functionally methylated genes. A novel epigenetic signature of eight hypermethylated genes was characterized that was able to identify mCRCs with poor prognosis, which had a CpG-island methylator phenotype (CIMP)-high and microsatellite instability (MSI)-like phenotype. Interestingly, methylation events were enriched in genes located on the q-arm of chromosomes 13 and 20, two chromosomal regions with gain/loss alterations associated with adenoma-to-carcinoma progression. Finally, the expression of the eight-genes signature and MSI-enriching genes was confirmed in oxaliplatin- and irinotecan-resistant CRC cell lines. These data reveal that the hypermethylation of specific genes may provide prognostic information that is able to identify a subgroup of mCRCs with poor prognosis.
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Gastrointestinal stromal tumours that are wild type for KIT and PDGFRA are referred to as WT GISTs. Of these tumours, SDH-deficient (characterized by the loss of SDHB) and quadruple WT GIST (KIT/PDGFRA/SDH/RAS-P WT) subgroups were reported to display a marked overexpression of FGF4, identifying a putative common therapeutic target for the first time. In SDH-deficient GISTs, methylation of an FGF insulator region was found to be responsible for the induction of FGF4 expression. In quadruple WT, recurrent focal duplication of FGF3/FGF4 was reported; however, how it induced FGF4 expression was not investigated. To assess whether overexpression of FGF4 in quadruple WT could be driven by similar epigenetic mechanisms as in SDH-deficient GISTs, we performed global and locus-specific (on FGF4 and FGF insulator) methylation analyses. However, no epigenetic alterations were detected. Conversely, we demonstrated that in quadruple WT GISTs, FGF4 expression and the structure of the duplication were intimately connected, with the copy of FGF4 closer to the ANO1 super-enhancer being preferentially expressed. In conclusion, we demonstrated that in quadruple WT GISTs, FGF4 overexpression is not due to an epigenetic mechanism but rather to the specific genomic structure of the duplication. Even if FGF4 overexpression is driven by different molecular mechanisms, these findings support an increasing biologic relevance of the FGFR pathway in WT GISTs, both in SDH-deficient and quadruple WT GISTs, suggesting that it may be a common therapeutic target.
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Factor 4 de Crecimiento de Fibroblastos/genética , Neoplasias Gastrointestinales/genética , Tumores del Estroma Gastrointestinal/genética , Duplicación de Gen , Regulación hacia Arriba , Anciano , Anoctamina-1/genética , Metilación de ADN , Elementos de Facilitación Genéticos , Epigénesis Genética , Femenino , Neoplasias Gastrointestinales/metabolismo , Tumores del Estroma Gastrointestinal/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogénicas c-kit/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Transducción de Señal , Succinato Deshidrogenasa/genética , Proteínas ras/genéticaRESUMEN
JAK2 V617F mutational status is an essential diagnostic index in myeloproliferative neoplasms (MPNs). Although widely used for detection of JAK2 V617F mutation in peripheral blood (PB), sensitive real-time quantitative PCR (qPCR) presents some methodological limitations. Recently, emerging alternative technologies, like digital droplet PCR (ddPCR), have been reported to overcome some of qPCR's technical drawbacks. The purpose of this study was to compare the diagnostic utility of ddPCR to qPCR for JAK2 V617F detection and quantification in samples from MPNs patients. Sensitivity and specificity of qPCR and ddPCR in the detection of the mutation were assessed by using a calibrator panel of mutated DNA on 195 JAK2 positive MPN samples. Based on our results, ddPCR proved to be a suitable, precise, and sensitive method for detection and quantification of the JAK2 V617F mutation.