331 research outputs found
Mucoepidermoid carcinoma associated with osteosarcoma in a true malignant mixed tumor of the submandibular region
True malignant mixed tumor, also known as carcinosarcoma, is a rare tumor of the salivary gland composed of both malignant epithelial and malignant mesenchymal elements. Frequently carcinosarcoma arises in the background of a preexisting pleomorphic adenoma; however, if no evidence of benign mixed tumor is present, the lesion is known as carcinosarcoma "de novo." We reported the first case of true malignant mixed tumor of the submandibular gland composed of high grade mucoepidermoid carcinoma associated with osteosarcoma. Case Presentation. A 69-year-old Caucasian male came to our department complaining of the appearance of an asymptomatic left submandibular neoformation progressively increasing in size over 3 months. We opted for surgical treatment. Histological examination confirmed the diagnosis of carcinosarcoma with the coexistence of high grade mucoepidermoid carcinoma and osteosarcoma. Conclusion. To the best of our knowledge, in the true malignant mixed tumor of the submandibular gland, mucoepidermoid carcinoma associated with osteosarcoma has never been previously reported
The rna-binding ubiquitin ligase mex3a affects glioblastoma tumorigenesis by inducing ubiquitylation and degradation of rig-i
Glioblastoma multiforme (GB) is the most malignant primary brain tumor in humans, with an overall survival of approximatively 15 months. The molecular heterogeneity of GB, as well as its rapid progression, invasiveness and the occurrence of drug-resistant cancer stem cells, limits the efficacy of the current treatments. In order to develop an innovative therapeutic strategy, it is mandatory to identify and characterize new molecular players responsible for the GB malignant phenotype. In this study, the RNA-binding ubiquitin ligase MEX3A was selected from a gene expression analysis performed on publicly available datasets, to assess its biological and still-unknown activity in GB tumorigenesis. We find that MEX3A is strongly up-regulated in GB specimens, and this correlates with very low protein levels of RIG-I, a tumor suppressor involved in differentiation, apoptosis and innate immune response. We demonstrate that MEX3A binds RIG-I and induces its ubiquitylation and proteasome-dependent degradation. Further, the genetic depletion of MEX3A leads to an increase of RIG-I protein levels and results in the suppression of GB cell growth. Our findings unveil a novel molecular mechanism involved in GB tumorigenesis and suggest MEX3A and RIG-I as promising therapeutic targets in GB
Expression of the HMGI(Y) gene products in human neuroblastic tumours correlates with differentiation status
HMGI and HMGY are splicing variants of the HMGI(Y) gene and together with HMGI-C, belong to a family of DNA binding proteins involved in maintaining active chromatin conformation and in the regulation of gene transcription. The expression of the HMGI(Y) gene is maximal during embryonic development, declines in adult differentiated tissues and is reactivated in most transformed cells in vitro and in many human cancers in vivo. The HMGI(Y) genomic locus is frequently rearranged in mesenchymal tumours, suggesting a biological role for HMGI(Y) gene products in tumour biology. HMGIs are both target and modulators of retinoic acid activity. In fact, HMGI(Y) gene expression is differentially regulated by retinoic acid in retinoid-sensitive and -resistant neuroblastoma cells, while HMGI-C participates in conferring retinoic acid resistance in some neuroblastoma cells. In this paper we show that HMGI and HMGY isoforms are equally regulated by retinoic acid in neuroblastoma cell lines at both RNA and protein levels. More importantly our immunohistochemical analysis shows that, although HMGI(Y) is expressed in all neuroblastic tumours, consistently higher levels are observed in less differentiated neuroblastomas compared to more differentiated ganglioneuromas, indicating that HMGI(Y) expression should be evaluated as a potential diagnostic and prognostic marker in neuroblastic tumours. © 2000 Cancer Research Campaign http://www.bjcancer.co
Unilateral vocal fold paralysis post-thyroidectomy: does early intervention allow for better voice recovery?
Objective: Thyroidectomy is the primary cause of unilateral vocal fold paralysis (UVFP). A delay in rehabilitation may cause dysfunctional phenomena and worsen dysphonia. The main aim is to investigate the impact of early Speech Therapy (ST) on voice recovery in UVFP post-thyroidectomy and propose an appropriate treatment schedule.
Patients and methods: 93 patients with UVFP were analysed. 72 presented transient paralysis and 21 permanent ones. Individuals with permanent paralysis were retrospectively divided in two groups. Group A was composed of 11 patients (8 F, 3 M; mean age: 50.5 ± 8.6) who received ST within 8 weeks; Group B comprised 10 patients (7 F, 3 M; mean age: 57 ± 11.5) treated after more than 8 weeks. Videolaryngostroboscopy (VLS) was assessed and both objective and subjective voice parameters were collected. The non-parametric Wilcoxon test was applied to the sample.
Results: The resolution of supraglottic compensations was observed in 91% of cases in Group A, whereas in only 40% of cases in Group B. A functional glottal closure occurred in 73% of patients in group A, while it was completely absent in group B. Group A showed a statistically significant difference between the values of Jitter, NHR, TMF and VHI collected pre-ST compared to that collected after 1 year. Conversely, a statistically significant difference was found only for VHI values in group B.
Conclusions: Early ST brings benefits to patients with permanent UVFP, both on voice recovery and on quality of life. A ST protocol should be applied both before and after thyroidectomy. The ST treatment should start early after surgery
Evidence-based renewal of the Italian guidelines for the use of antiretroviral agents and the diagnostic-clinical management of HIV-1 infected persons
The Italian Society for Infectious and Tropical Diseases (SIMIT) in collaboration with the Technical Health Committee (Sections L and M) of the Italian Ministry of Health have supported the renewal of the recommendations for the Italian guidelines for the use of antiretroviral agents and the diagnostic-clinical management of HIV-1 infected persons. This publication summarizes the latest updates to the 2017 version of the Italian Guidelines for the management of HIV-1 infected patients and the use of antiretroviral drugs. New recommendations were released framing the clinical questions the use of antiretrovirals according to the Patient Intervention Comparator Outcome (PICO) methodology and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Diagnostic tools for immunological and virological monitoring, when to start, what to start, optimization and therapeutic failure were updated in order to include the recommendation obtained with these newly developed methods. For a complete review of clinical and therapeutic relevant topics we refer the reader to the extended version of the Guidelines
Blockade of EIF5A hypusination limits colorectal cancer growth by inhibiting MYC elongation
Eukaryotic Translation Initiation Factor 5A (EIF5A) is a translation factor regulated by hypusination, a unique posttranslational modification catalyzed by deoxyhypusine synthetase (DHPS) and deoxyhypusine hydroxylase (DOHH) starting from the polyamine spermidine. Emerging data are showing that hypusinated EIF5A regulates key cellular processes such as autophagy, senescence, polyamine homeostasis, energy metabolism, and plays a role in cancer. However, the effects of EIF5A inhibition in preclinical cancer models, the mechanism of action, and specific translational targets are still poorly understood. We show here that hypusinated EIF5A promotes growth of colorectal cancer (CRC) cells by directly regulating MYC biosynthesis at specific pausing motifs. Inhibition of EIF5A hypusination with the DHPS inhibitor GC7 or through lentiviral-mediated knockdown of DHPS or EIF5A reduces the growth of various CRC cells. Multiplex gene expression analysis reveals that inhibition of hypusination impairs the expression of transcripts regulated by MYC, suggesting the involvement of this oncogene in the observed effect. Indeed, we demonstrate that EIF5A regulates MYC elongation without affecting its mRNA content or protein stability, by alleviating ribosome stalling at five distinct pausing motifs in MYC CDS. Of note, we show that blockade of the hypusination axis elicits a remarkable growth inhibitory effect in preclinical models of CRC and significantly reduces the size of polyps in APCMin/+ mice, a model of human familial adenomatous polyposis (FAP). Together, these data illustrate an unprecedented mechanism, whereby the tumor-promoting properties of hypusinated EIF5A are linked to its ability to regulate MYC elongation and provide a rationale for the use of DHPS/EIF5A inhibitors in CRC therapy
Impact of social determinants on antiretroviral therapy access and outcomes entering the era of universal treatment for people living with HIV in Italy
Background: Social determinants are known to be a driving force of health inequalities, even in high income countries. Aim of our study was to determine if these factors can limit antiretroviral therapy (ART) access, outcome and retention in care of people living with HIV (PLHIV) in Italy. Methods: All ART naĂŻve HIV+ patients (pts) of Italian nationality enrolled in the ICONA Cohort from 2002 to 2016 were included. The association of socio-demographic characteristics (age, sex, risk factor for HIV infection, educational level, occupational status and residency area) with time to: ART initiation (from the first positive anti-HIV test), ART regimen discontinuation, and first HIV-RNA < 50 cp/mL, were evaluated by Cox regression analysis, Kaplan Meier method and log-rank test. Results: A total of 8023 HIV+ pts (82% males, median age at first pos anti-HIV test 36 years, IQR: 29-44) were included: 6214 (77.5%) started ART during the study period. Women, people who inject drugs (PWID) and residents in Southern Italy presented the lowest levels of education and the highest rate of unemployment compared to other groups. Females, pts aged > 50 yrs., unemployed vs employed, and people with lower educational levels presented the lowest CD4 count at ART initiation compared to other groups. The overall median time to ART initiation was 0.6 years (yrs) (IQR 0.1-3.7), with a significant decrease over time [2002-2006 = 3.3 yrs. (0.2-9.4); 2007-2011 = 1.0 yrs. (0.1-3.9); 2012-2016 = 0.2 yrs. (0.1-2.1), p < 0.001]. By multivariate analysis, females (p < 0.01) and PWID (p < 0.001), presented a longer time to ART initiation, while older people (p < 0.001), people with higher educational levels (p < 0.001), unemployed (p = 0.02) and students (p < 0.001) were more likely to initiate ART. Moreover, PWID, unemployed vs stable employed, and pts. with lower educational levels showed a lower 1-year probability of achieving HIV-RNA suppression, while females, older patients, men who have sex with men (MSM), unemployed had higher 1-year risk of first-line ART discontinuation. Conclusions: Despite median time to ART start decreased from 2002 to 2016, socio-demographic factors still contribute to disparities in ART initiation, outcome and durability
Nuclear Factor of Activated T Cells-dependent Down-regulation of the Transcription Factor Glioma-associated Protein 1 (GLI1) Underlies the Growth Inhibitory Properties of Arachidonic Acid
Numerous reports have demonstrated a tumor inhibitory effect of polyunsaturated fatty acids (PUFAs). However, the molecular mechanisms modulating this phenomenon are in part poorly understood. Here, we provide evidence of a novel antitumoral mechanism of the PUFA arachidonic acid (AA). In vivo and in vitro experiments showed that AA treatment decreased tumor growth and metastasis, and increased apoptosis. Molecular analysis of this effect showed significantly reduced expression of a subset of antiapoptotic proteins, including BCL2, BFL1/A1 and 4-1BB, in AA-treated cells. We demonstrated that downregulation of the transcription factor GLI1 in AA-treated cells is the underlying mechanism controlling BCL2, BFL1/A1 and 4-1BB expression. Using luciferase reporters, chromatin immunoprecipitation, and expression studies, we found that GLI1 binds to the promoter of these antiapoptotic molecules, and regulates their expression and promoter activity. We provide evidence that AA-induced apoptosis and downregulation of antiapoptotic genes can be inhibited by overexpressing GLI1 in AA-sensitive cells. Conversely, inhibition of GLI1 mimics AA treatments, leading to decreased tumor growth, cell viability and expression of antiapoptotic molecules. Further characterization showed that AA represses GLI1 expression by stimulating NFATc1 nuclear translocation, which then binds the GLI1 promoter and represses its transcription. AA was shown to increase reactive oxygen species. Treatment with antioxidants reduced the AA-induced apoptosis, downregulation of GLI1 and NFATc1 activation, indicating that NFATc1 activation and GLI1 repression require the generation of reactive oxygen species. Collectively, these results define a novel mechanism underlying AA antitumoral functions that may serve as a foundation for the future PUFA-based therapeutic approaches
The MRN complex is transcriptionally regulated by MYCN during neural cell proliferation to control replication stress
The MRE11/RAD50/NBS1 (MRN) complex is a major sensor of DNA double strand breaks, whose role in controlling faithful DNA replication and preventing replication stress is also emerging. Inactivation of the MRN complex invariably leads to developmental and/or degenerative neuronal defects, the pathogenesis of which still remains poorly understood. In particular, NBS1 gene mutations are associated with microcephaly and strongly impaired cerebellar development, both in humans and in the mouse model. These phenotypes strikingly overlap those induced by inactivation of MYCN, an essential promoter of the expansion of neuronal stem and progenitor cells, suggesting that MYCN and the MRN complex might be connected on a unique pathway essential for the safe expansion of neuronal cells. Here, we show that MYCN transcriptionally controls the expression of each component of the MRN complex. By genetic and pharmacological inhibition of the MRN complex in a MYCN overexpression model and in the more physiological context of the Hedgehog-dependent expansion of primary cerebellar granule progenitor cells, we also show that the MRN complex is required for MYCN-dependent proliferation. Indeed, its inhibition resulted in DNA damage, activation of a DNA damage response, and cell death in a MYCN- and replication-dependent manner. Our data indicate the MRN complex is essential to restrain MYCN-induced replication stress during neural cell proliferation and support the hypothesis that replication-born DNA damage is responsible for the neuronal defects associated with MRN dysfunctions.Cell Death and Differentiation advance online publication, 12 June 2015; doi:10.1038/cdd.2015.81
1H-NMR metabolomics reveals the Glabrescione B exacerbation of glycolytic metabolism beside the cell growth inhibitory effect in glioma
BACKGROUND: Glioma is the most common and primary brain tumors in adults. Despite the available multimodal therapies, glioma patients appear to have a poor prognosis. The Hedgehog (Hh) signaling is involved in tumorigenesis and emerged as a promising target for brain tumors. Glabrescione B (GlaB) has been recently identified as the first direct inhibitor of Gli1, the downstream effector of the pathway.
METHODS: We established the overexpression of Gli1 in murine glioma cells (GL261) and GlaB effect on cell viability. We used 1H-nuclear magnetic resonance (NMR) metabolomic approach to obtain informative metabolic snapshots of GL261 cells acquired at different time points during GlaB treatment. The activation of AMP activated protein Kinase (AMPK) induced by GlaB was established by western blot. After the orthotopic GL261 cells injection in the right striatum of C57BL6 mice and the intranasal (IN) GlaB/mPEG5kDa-Cholane treatment, the tumor growth was evaluated. The High Performance Liquid Chromatography (HPLC) combined with Mass Spectrometry (MS) was used to quantify GlaB in brain extracts of treated mice.
RESULTS: We found that GlaB affected the growth of murine glioma cells both in vitro and in vivo animal model. Using an untargeted 1H-NMR metabolomic approach, we found that GlaB stimulated the glycolytic metabolism in glioma, increasing lactate production. The high glycolytic rate could in part support the cytotoxic effects of GlaB, since the simultaneous blockade of lactate efflux with \u3b1-cyano-4-hydroxycinnamic acid (ACCA) affected glioma cell growth. According to the metabolomic data, we found that GlaB increased the phosphorylation of AMPK, a cellular energy sensor involved in the anabolic-to-catabolic transition.
CONCLUSIONS: Our results indicate that GlaB inhibits glioma cell growth and exacerbates Warburg effect, increasing lactate production. In addition, the simultaneous blockade of Gli1 and lactate efflux amplifies the anti-tumor effect in vivo, providing new potential therapeutic strategy for this brain tumor
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