Leukodystrophies are a heterogeneous group of inherited neurodegenerative disorders characterized by abnormal white matter visible by brain imaging. It is estimated that at least 30% to 40% of individuals remain without a precise diagnosis despite extensive investigations. We mapped tremor-ataxia with central hypomyelination (TACH) to 10q22.3-23.1 in French-Canadian families and sequenced candidate genes within this interval. Two missense and one insertion mutations in five individuals with TACH were uncovered in POLR3A, which codes for the largest subunit of RNA polymerase III (Pol III). Because these families were mapped to the same locus as leukodystrophy with oligodontia (LO) and presented clinical and radiological overlap with individuals with hypomyelination, hypodontia and hypogonadotropic hypogonadism (4H) syndrome, we sequenced this gene in nine individuals with 4H and eight with LO. In total, 14 recessive mutations were found in 19 individuals with TACH, 4H, or LO, establishing that these leukodystrophies are allelic. No individual was found to carry two nonsense mutations. Immunoblots on 4H fibroblasts and on the autopsied brain of an individual diagnosed with 4H documented a significant decrease in POLR3A levels, and there was a more significant decrease in the cerebral white matter compared to that in the cortex. Pol III has a wide set of target RNA transcripts, including all nuclear-coded tRNA. We hypothesize that the decrease in POLR3A leads to dysregulation of the expression of certain Pol III targets and thereby perturbs cytoplasmic protein synthesis. This type of broad alteration in protein synthesis is predicted to occur in other leukoencephalopathies such as hypomyelinating leukodystrophy-3, caused by mutations in aminoacyl-tRNA synthetase complex-interacting multifunctional protein 1 (AIMP1).

Background:Chemotherapy resistance is a major determinant of poor overall survival rates in high-grade serous ovarian cancer (HGSC). We have previously shown that gene expression alterations affecting the NF-κB pathway characterise chemotherapy resistance in HGSC, suggesting that the regulation of an immune response may be associated with this phenotype.Methods:Given that intrinsic drug resistance pre-exists and is governed by both tumour and host factors, the current study was performed to examine the cross-talk between tumour inflammatory microenvironment and cancer cells, and their roles in mediating differential chemotherapy response in HGSC patients. Expression profiling of a panel of 184 inflammation-related genes was performed in 15 chemoresistant and 19 chemosensitive HGSC tumours using the NanoString nCounter platform.Results:A total of 11 significantly differentially expressed genes were found to distinguish the two groups. As STAT1 was the most significantly differentially expressed gene (P=0.003), we validated the expression of STAT1 protein by immunohistochemistry using an independent cohort of 183 (52 resistant and 131 sensitive) HGSC cases on a primary tumour tissue microarray. Relative expression levels were subjected to Kaplan–Meier survival analysis and Cox proportional hazard regression models.Conclusions:This study confirms that higher STAT1 expression is significantly associated with increased progression-free survival and that this protein together with other mediators of tumour–host microenvironment can be applied as a novel response predictive biomarker in HGSC. Furthermore, an overall underactive immune microenvironment suggests that the pre-existing state of the tumour immune microenvironment could determine response to chemotherapy in HGSC.

Conclusion. This is the first report establishing that AFAs in SSc are strongly correlated with anti-topo I and, furthermore, that anti-topo I antibodies themselves display AFA activity by reacting with determinants at the fibroblast surface.

GH has been demonstrated to play a physiological role in the priming of macrophages for tumor necrosis factor-alpha (TNF alpha) synthesis. Although evidence has been presented that GH exerts this effect by an indirect mechanism, the mediators of GH stimulation of TNF alpha synthesis have not been identified. Because insulin-like growth factor-I (IGF-I) is a major mediator of many GH effects, in the present study we investigated the direct in vitro effect of this growth factor on macrophage TNF alpha production. Treatment of murine macrophages with physiological concentrations of IGF-I (0.13-130 nM) enhanced both basal and lipopolysaccharide-stimulated macrophage TNF alpha release and messenger RNA levels. Induction of basal TNF alpha production was also observed after treatment of the cells with supraphysiological concentrations of insulin (130-1300 nM). Exposure of human monocytes to IGF-I led to a similar increase of basal TNF alpha production and messenger RNA expression. Preexposure of macrophages with specific antibodies against IGF-I and IGF-I receptor before IGF-I addition resulted in a complete abrogation of the stimulatory effect of IGF-I on TNF alpha production, indicating that specific binding of IGF-I to its receptor is required for macrophage TNF alpha induction by IGF-I. In contrast to the stimulatory effect of IGF-I, neither GH (0.1-10 micrograms/ml) nor IGF-II (0.13-130 nM) enhanced macrophage TNF alpha release in vitro. To assess the role of the tyrosine kinase system in mediating IGF-I-induced basal TNF alpha production, macrophages were preincubated with the specific tyrosine kinase inhibitors, genistein and tyrphostin A9, before IGF-I exposure. Addition of these compounds resulted in a dose-dependent inhibition of the stimulatory effect of IGF-I on macrophage TNF alpha release, indicating that protein tyrosine kinase activation is required for TNF alpha stimulation by IGF-I. Taken together, these results demonstrate that IGF-I is a monocyte/macrophage activating factor that enhances TNF alpha production, and that such effect is mediated via the IGF-I receptor and involves tyrosine kinase activation.

High‐grade serous ovarian carcinoma (HGSC) accounts for 70% of all epithelial ovarian cancers but clinical management is challenged by a lack of accurate prognostic and predictive biomarkers of chemotherapy response. This study evaluated the role of Signal Transducer and Activator of Transcription 1 (STAT1) as an independent prognostic and predictive biomarker and its correlation with intratumoural CD8+ T cells in a second independent biomarker validation study. Tumour STAT1 expression and intratumoural CD8+ T cell infiltration were assessed by immunohistochemistry as a multicentre validation study conducted on 734 chemotherapy‐naïve HGSCs. NanoString‐based profiling was performed to correlate expression of STAT1 target genes CXCL9, CXCL10 and CXCL11 with CD8A transcript expression in 143 primary tumours. Multiplexed cytokine analysis of pre‐treatment plasma from resistant and sensitive patients was performed to assess systemic levels of STAT1‐induced cytokines. STAT1 was validated as a prognostic and predictive biomarker in both univariate and multivariate models and its expression correlated significantly with intra‐epithelial CD8+ T cell infiltration in HGSC. STAT1 levels increased the prognostic and predictive value of intratumoural CD8+ T cells, confirming their synergistic role as biomarkers in HGSC. In addition, expression of STAT1 target genes (CXCL9, CXCL10 and CXCL11) correlated significantly with levels of, and CD8A transcripts from intratumoural CD8+ T cells within the resistant and sensitive tumours. Our findings provide compelling evidence that high levels of STAT1, STAT1‐induced chemokines and CD8+ T cells correlate with improved chemotherapy response in HGSC. These results identify STAT1 and its target genes as novel biomarkers of chemosensitivity in HGSC. These findings provide new translational opportunities for patient stratification for immunotherapies based on emerging biomarkers of inflammation in HGSC. An improved understanding of the role of interferon‐inducible genes will be foundational for developing immunomodulatory therapies in ovarian cancer.

Objective. We have previously found that the CENP-B nuclear autoantigen, which is specifically targeted by autoantibodies in the limited cutaneous form of systemic sclerosis, behaved as a potent migratory factor for human pulmonary artery smooth muscle cells

BackgroundCentrosomes function primarily as microtubule-organizing centres and play a crucial role during mitosis by organizing the bipolar spindle. In addition to this function, centrosomes act as reaction centers where numerous key regulators meet to control cell cycle progression. One of these factors involved in genome stability, the checkpoint kinase CHK2, was shown to localize at centrosomes throughout the cell cycle.ResultsHere, we show that CHK2 only localizes to centrosomes during mitosis. Using wild-type and CHK2−/− HCT116 human colon cancer cells and human osteosarcoma U2OS cells depleted for CHK2 with small hairpin RNAs we show that several CHK2 antibodies are non-specific and cross-react with an unknown centrosomal protein(s) by immunofluorescence. To characterize the localization of CHK2, we generated cells expressing inducible GFP-CHK2 and Flag-CHK2 fusion proteins. We show that CHK2 localizes to the nucleus in interphase cells but that a fraction of CHK2 associates with the centrosomes in a Polo-like kinase 1-dependent manner during mitosis, from early mitotic stages until cytokinesis.ConclusionOur findings demonstrate that a subpopulation of CHK2 localizes at the centrosomes in mitotic cells but not in interphase. These results are consistent with previous reports supporting a role for CHK2 in the bipolar spindle formation and the timely progression of mitosis.

The purpose of this study was to determine the prognostic value and oncogenic pathways associated to miRNA expression in squamous cell carcinoma of the oral tongue and to link these miRNA candidates with potential gene targets. We performed a miRNA screening within our institutional cohort (n = 58 patients) and reported five prognostic targets including a cluster of four co-expressed miRNAs (miR-18a, miR-92a, miR-103, and miR-205). Multivariate analysis showed that expression of miR-548b (p = 0.007) and miR-18a (p = 0.004, representative of co-expressed miRNAs) are independent prognostic markers for squamous cell carcinoma of the oral tongue. These findings were validated in The Cancer Genome Atlas (TCGA) cohort (n = 131) for both miRNAs (miR-548b: p = 0.027; miR-18a: p = 0.001). Bioinformatics analysis identified PTEN and ACTN4 as direct targets of the four co-expressed miRNAs and miR-548b, respectively. Correlations between the five identified miRNAs and their respective targeted genes were validated in the two merged cohorts and were concordantly significant (miR-18a/PTEN: p < 0.0001; miR-92a/PTEN: p = 0.0008; miR-103/PTEN: p = 0.008; miR-203/PTEN: p = 0.019; miR-548b/ACTN4: p = 0.009).