217 research outputs found
Liquid biopsy in the assessment of microRNAs in oral squamous cell carcinoma : a systematic review
The identification of non-invasive biomarkers from biological fluids collected by liquid biopsy provides new horizons for individualized therapeutic strategies and improves clinical decision-making in OSCC patients. Circulating microRNAs have emerged as
Auto ADP-ribosylation of NarE, a Neisseria meningitidis ADP-ribosyltransferase, regulates its catalytic activities
NarE is an arginine-specific mono-ADPribosyltransferase
identified in Neisseria meningitidis
that requires the presence of iron in a structured
cluster for its enzymatic activities. In this study, we
show that NarE can perform auto-ADP-ribosylation.
This automodification occurred in a time- and NADconcentration-
dependent manner; was inhibited by novobiocin,
an ADP-ribosyltransferase inhibitor; and did
not occur when NarE was heat inactivated. No reduction
in incorporation was evidenced in the presence of
high concentrations of ATP, GTP, ADP-ribose, or nicotinamide,
which inhibits NAD-glycohydrolase, impeding
the formation of free ADP-ribose. Based on the
electrophoretic profile of NarE on auto-ADP-ribosylation
and on the results of mutagenesis and mass
spectrometry analysis, the auto-ADP-ribosylation appeared
to be restricted to the addition of a single
ADP-ribose. Chemical stability experiments showed
that the ADP-ribosyl linkage was sensitive to hydroxylamine,
which breaks ADP-ribose-arginine bonds. Sitedirected
mutagenesis suggested that the auto-ADP-ribosylation
site occurred preferentially on the R7 residue,
which is located in the region I of the ADP-ribosyltransferase
family. After auto-ADP-ribosylation, NarE
showed a reduction in ADP-ribosyltransferase activity,
while NAD-glycohydrolase activity was increased. Overall,
our findings provide evidence for a novel intramolecular
mechanism used by NarE to regulate its enzymatic
activities.—Picchianti, M., Del Vecchio, M., Di
Marcello, F., Biagini, M., Veggi, D., Norais N., Rappuoli,
R., Pizza, M., Balducci, E. Auto ADP-ribosylation
of NarE, a Neisseria meningitidis ADP-ribosyltransferase,
regulates its catalytic activities. FASEB J
A novel RAB39B mutation and concurrent de novo NF1 mutation in a boy with neurofibromatosis type 1, intellectual disability, and autism: a case report
Background
Mutations in RAB39B at Xq28 causes a rare form of X-linked intellectual disability (ID) and Parkinson’s disease. Neurofibromatosis type 1 (NF1) is caused by heterozygous mutations in NF1 occurring de novo in about 50% of cases, usually due to paternal gonadal mutations. This case report describes clinical and genetic findings in a boy with the occurrence of two distinct causative mutations in NF1 and RAB39B explaining the observed phenotype.
Case presentation
Here we report a 7-year-old boy with multiple café-au-lait macules (CALMs) and freckling, severe macrocephaly, peculiar facial gestalt, severe ID with absent speech, epilepsy, autistic traits, self-harming, and aggressiveness. Proband is an only child born to a father aged 47. Parents did not present signs of NF1, while a maternal uncle showed severe ID, epilepsy, and tremors.By RNA analysis of NF1, we identified a de novo splicing variant (NM_000267.3:c.6579+2T>C) in proband, which explained NF1 clinical features but not the severe ID, behavioral problems, and aggressiveness. Family history suggested an X-linked condition and massively parallel sequencing of X-exome identified a novel RAB39B mutation (NM_171998.2:c.436_447del) in proband, his mother, and affected maternal uncle, subsequently validated by Sanger sequencing in these and other family members.
Conclusions
The case presented here highlights how concurrent genetic defects should be considered in NF1 patients when NF1 mutations cannot reasonably explain all the observed clinical features
Photo-biomodulation as a prevention modality of oral mucositis in patients undergoing allogeneic hematopoietic stem cell transplantation
The aim of the study was to observe the eectiveness of a photo-biomodulation (PBM)
protocol for the prevention of oral mucositis (OM) in patients undergoing allogeneic hematopoietic
stem cell transplantation (aHSCT). A case-control study was conducted on 40 patients undergoing
aHSCT. The patients were divided into two groups; the preventive group (PG) included 20 patients
(7 females and 13 males) who were subjected to intra-oral PBM for five sessions a week, starting one
day before the conditioning regimen and continuing until the 10th day after transplantation (D+10).
In each session, ten points on the at-risk mucosal surfaces were irradiated using a double diode
laser that emits two wavelengths simultaneously at 650 nm and at 904–910 nm with the following
parameters at each point: energy of 4 J, and power of 88.9 mW. The control group (CG) included
20 patients (10 females and 10 males) who were not subjected to laser therapy and were selected
retrospectively to compare the obtained results. For all patients, OM was assessed by the World
Health Organization (WHO) grading scale. Eight patients in the PG did not experience OM during
their hospitalization period (with grade 0). Severe OM was observed in 40% of the patients in the
PG, while in the CG, severe OM was shown in 85% of the patients. The mean duration of OM in the
PG was significantly lower than that of CG (4.7 days in the PG and 15 days in the CG) (p < 0.001).
The study demonstrated that the preventive PBM protocol reduced the severity and duration of OM
in patients undergoing aHSCT
DIAGNOSTIC ACCURACY OF BONE SCINTIGRAPHY IN THE EARLY PREDICTION OF MRONJ
Since Medication-Related Osteonecrosis of the Jaw (MRONJ) is challenging to treat, prevention and early detection are fundamental to limit progression. While some imaging techniques such as computed tomography (CT) scans are helpful to estimate the extent of osteonecrosis in clinically evident MRONJ, methods for early detection and identification of patients at risk for MRONJ need further investigations. The aim of our retrospective study was to evaluate the role of bone scintigraphy (BS) in the early prediction of MRONJ. BS of patients treated with antiangiogenic or antiresorptive therapy for bone metastases were evaluated for pathological tracer uptake of the jaws. Sensitivity, specificity, predictive values of BS for the prediction of MRONJ were investigated. Moreover, the latency from the first presence of pathological tracer uptake in BS to clinically evident MRONJ was determined. The significance of pathologic BS for MRONJ detection was calculated by Fisher's exact test and the odds ratio was determined.A total of 19 patients with representative BS were recruited from our Department database. Whole body BS in anterior and posterior positions were reviewed by a specialist in nuclear medicine, blinded to MRONJ diagnosis, for pathological tracer uptake of the jaws. Results were compared to development of clinically evident MRONJ. Sensitivity and specificity of BS for MRONJ prediction were respectively 90% and 82%. Positive and negative predictive values were 64% and 96%, respectively. Median time from the first presence of pathological tracer uptake in BS to clinically evident MRONJ was 20.3 months (range 7–41). Pathologic findings on BS were significantly (p < 0.001) more often observed in patients who developed MRONJ compared to patients who did not. The risk to develop MRONJ was 41.4-fold increased when BS was pathologic. According to our results, BS is an accurate method for the prediction of MRONJ
Telocytes are the physiological counterpart of inflammatory fibroid polyps and PDGFRA-mutant GISTs
PDGFRA mutations in the gastrointestinal (GI) tract can cause GI stromal tumour (GIST) and inflammatory fibroid polyp (IFP). Hitherto no cell type has been identified as a physiological counterpart of the latter, while interstitial Cajal cells (ICC) are considered the precursor of the former. However, ICC hyperplasia (ICCH), which strongly supports the ICC role in GIST pathogenesis, has been identified in germline KIT-mutant settings but not in PDGFRA-mutant ones, challenging the precursor role of ICC for PDGFRA-driven GISTs. Telocytes are a recently described interstitial cell type, CD34+/PDGFRA+. Formerly considered fibroblasts, they are found in many organs, including the GI tract where they are thought to be involved in neurotransmission. Alongside IFPs and gastric GISTs, GI wall \u201cfibrosis\u201d has been reported in germline PDGFRA-mutants. Taking the opportunity offered by its presence in a germline PDGFRA-mutant individual, we demonstrate that this lesion is sustained by hyperplastic telocytes, constituting the PDGFRA-mutant counterpart of germline KIT mutation-associated ICCH. Moreover, our findings support a pathogenetic relationship between telocyte hyperplasia and both IFPs and PDGFRA-mutant GISTs. We propose the term \u201ctelocytoma\u201d for defining IFP, as it conveys both the pathogenetic (neoplastic) and histotypic (\u201ctelocytary\u201d) essence of this tumour, unlike IFP, which rather evokes an inflammatory-hyperplastic lesion
Gut Microbiota, Metabolome, and Body Composition Signatures of Response to Therapy in Patients with Advanced Melanoma
Despite the recent breakthroughs in targeted and immunotherapy for melanoma, the overall survival rate remains low. In recent years, considerable attention has been paid to the gut microbiota and other modifiable patient factors (e.g., diet and body composition), though their role in influencing therapeutic responses has yet to be defined. Here, we characterized a cohort of 31 patients with unresectable IIIC-IV-stage cutaneous melanoma prior to initiation of targeted or first-line immunotherapy via the following methods: (i) fecal microbiome and metabolome via 16S rRNA amplicon sequencing and gas chromatography/mass spectrometry, respectively, and (ii) anthropometry, body composition, nutritional status, physical activity, biochemical parameters, and immunoprofiling. According to our data, patients subsequently classified as responders were obese (i.e., with high body mass index and high levels of total, visceral, subcutaneous, and intramuscular adipose tissue), non-sarcopenic, and enriched in certain fecal taxa (e.g., Phascolarctobacterium) and metabolites (e.g., anethole), which were potentially endowed with immunostimulatory and oncoprotective activities. On the other hand, non-response was associated with increased proportions of Streptococcus, Actinomyces, Veillonella, Dorea, Fusobacterium, higher neutrophil levels (and a higher neutrophil-to-lymphocyte ratio), and higher fecal levels of butyric acid and its esters, which also correlated with decreased survival. This exploratory study provides an integrated list of potential early prognostic biomarkers that could improve the clinical management of patients with advanced melanoma, in particular by guiding the design of adjuvant therapeutic strategies to improve treatment response and support long-term health improvement
The type 1 diabetes gene TYK2 regulates beta-cell development and its responses to interferon-alpha
The TYK2 gene is associated with development of type 1 diabetes. Here the authors show that TYK2 regulates beta-cell development, but at the same time TYK2 inhibition in the islets prevents IFN alpha responses and enhances their survival against CD8(+) T-cell cytotoxicity; representing a potent therapeutic target to halt T1D progression. Type 1 diabetes (T1D) is an autoimmune disease that results in the destruction of insulin producing pancreatic beta-cells. One of the genes associated with T1D is TYK2, which encodes a Janus kinase with critical roles in type-Iota interferon (IFN-Iota) mediated intracellular signalling. To study the role of TYK2 in beta-cell development and response to IFN alpha, we generated TYK2 knockout human iPSCs and directed them into the pancreatic endocrine lineage. Here we show that loss of TYK2 compromises the emergence of endocrine precursors by regulating KRAS expression, while mature stem cell-islets (SC-islets) function is not affected. In the SC-islets, the loss or inhibition of TYK2 prevents IFN alpha-induced antigen processing and presentation, including MHC Class Iota and Class Iota Iota expression, enhancing their survival against CD8(+) T-cell cytotoxicity. These results identify an unsuspected role for TYK2 in beta-cell development and support TYK2 inhibition in adult beta-cells as a potent therapeutic target to halt T1D progression.Peer reviewe
Adjuvant pembrolizumab versus placebo in resected high-risk stage II melanoma: Health-related quality of life from the randomized phase 3 KEYNOTE-716 study
Background: Adjuvant pembrolizumab significantly improved recurrence-free survival (RFS) versus placebo in resected stage IIB and IIC melanoma in the phase 3 KEYNOTE-716 study. Health-related quality of life (HRQoL) results are reported. Methods: Patients were randomly assigned 1:1 to pembrolizumab 200 mg (2 mg/kg, patients ≥ 12 to \u3c 18 years) Q3W or placebo for ≤ 17 cycles or until disease recurrence, unacceptable toxicity, or withdrawal. Change from baseline in EORTC QLQ-C30 global health status (GHS)/quality of life (QoL) was a prespecified exploratory end point. Change in EORTC QLQ-C30 functioning, symptom, and single-item scales, and EQ-5D-5L visual analog scale (VAS) were also summarized. Primary analyses were performed at week 48 to ensure adequate completion/compliance. The HRQoL population comprised patients who received ≥ 1 dose of treatment and completed ≥ 1 assessment. Results: The HRQoL population included 969 patients (pembrolizumab, n = 483; placebo, n = 486). Compliance at week 48 was ≥ 80 % for both instruments. EORTC QLQ-C30 GHS/QoL, physical functioning, role functioning, and EQ-5D-5L VAS scores were stable from baseline to week 48 in both arms, with no clinically meaningful decline observed. Scores did not differ significantly between pembrolizumab and placebo. EORTC QLQ-C30 GHS/QoL, physical functioning, role functioning, and EQ-5D-5L VAS scores remained stable through week 96 in both arms. Conclusions: HRQoL was stable with adjuvant pembrolizumab, with no clinically meaningful decline observed. Change from baseline in HRQoL was similar between arms. These results, in conjunction with the improved RFS and manageable safety previously reported, support the use of adjuvant pembrolizumab for high-risk stage II melanoma
Abnormal neutrophil signature in the blood and pancreas of presymptomatic and symptomatic type 1 diabetes
BACKGROUND. Neutrophils and their inflammatory mediators are key pathogenic components in multiple autoimmune diseases, while their role in human type 1 diabetes (T1D), a disease that progresses sequentially through identifiable stages prior to the clinical onset, is not well understood. We previously reported that the number of circulating neutrophils is reduced in patients with T1D and in presymptomatic at-risk subjects. The aim of the present work was to identify possible changes in circulating and pancreas-residing neutrophils throughout the disease course to better elucidate neutrophil involvement in human T1D.
METHODS. Data collected from 389 subjects at risk of developing T1D, and enrolled in 4 distinct studies performed by TrialNet, were analyzed with comprehensive statistical approaches to determine whether the number of circulating neutrophils correlates with pancreas function. To obtain a broad analysis of pancreas-infiltrating neutrophils throughout all disease stages, pancreas sections collected worldwide from 4 different cohorts (i.e., nPOD, DiViD, Siena, and Exeter) were analyzed by immunohistochemistry and immunofluorescence. Finally, circulating neutrophils were purified from unrelated nondiabetic subjects and donors at various T1D stages and their transcriptomic signature was determined by RNA sequencing.
RESULTS. Here, we show that the decline in β cell function is greatest in individuals with the lowest peripheral neutrophil numbers. Neutrophils infiltrate the pancreas prior to the onset of symptoms and they continue to do so as the disease progresses. Of interest, a fraction of these pancreasinfiltrating neutrophils also extrudes neutrophil extracellular traps (NETs), suggesting a tissue-specific pathogenic role. Whole-transcriptome analysis of purified blood neutrophils revealed a unique molecular signature that is distinguished by an overabundance of IFN-associated genes; despite being healthy, said signature is already present in T1D-autoantibody-negative at-risk subjects.
CONCLUSIONS. These results reveal an unexpected abnormality in neutrophil disposition both in the circulation and in the pancreas of presymptomatic and symptomatic T1D subjects, implying that targeting neutrophils might represent a previously unrecognized therapeutic modality
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