1,195 research outputs found
Polyphenon E enhances the antitumor immune response in neuroblastoma by inactivating myeloid suppressor cells
This is the author's accepted manuscript. The final published article is available from the link below. Note: In this manuscript as well as in the original published version of this article the word "Polyphenon" was incorrectly spelled in the title as "Polyphenol."Purpose: Neuroblastoma is a rare childhood cancer whose high risk, metastatic form has a dismal outcome in spite of aggressive therapeutic interventions. The toxicity of drug treatments is a major problem in this pediatric setting. In this study, we investigated whether Polyphenon E, a clinical grade mixture of green tea catechins under evaluation in multiple clinical cancer trials run by the National Cancer Institute (Bethesda, MD), has anticancer activity in mouse models of neuroblastoma.
Experimental Design: We used three neuroblastoma models: (i) transgenic TH-MYCN mouse developing spontaneous neuroblastomas; (ii) nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice xenotransplanted with human SHSY5Y cells; and (iii) A/J mice transplanted with syngeneic Neuro 2A cells. Mice were randomized in control and Polyphenon E–drinking groups. Blood from patients with neuroblastoma and normal controls was used to assess the phenotype and function of myeloid cells.
Results: Polyphenon E reduced the number of tumor-infiltrating myeloid cells, and inhibited the development of spontaneous neuroblastomas in TH-MYCN transgenic mice. In therapeutic models of neuroblastoma in A/J, but not in immunodeficient NOD/SCID mice, Polyphenon E inhibited tumor growth by acting on myeloid-derived suppressor cells (MDSC) and CD8 T cells. In vitro, Polyphenon E impaired the development and motility of MDSCs and promoted differentiation to more neutrophilic forms through the 67 kDa laminin receptor signaling and induction of granulocyte colony-stimulating factor. The proliferation of T cells infiltrating a patient metastasis was reactivated by Polyphenon E.
Conclusions: These findings suggest that the neuroblastoma-promoting activity of MDSCs can be manipulated pharmacologically in vivo and that green tea catechins operate, at least in part, through this mechanism.SPARKS, Research in Childhood Cancer, the CGD
Research Trust, and the Wellcome Trust
Functional identification and investigation of genes initiating chromosomal instability using CRISPR activation and high-throughput automated image analysis
Chromosomal instability (CIN), the dynamic state where cells experience increased structural and/or numerical chromosome segregation errors, is prevalent in cancer, where it contributes to aneuploidy and tumour evolution. Despite its profound consequences on human health, initiation of CIN in the early stages of tumourigenesis is not well understood. In this work multiple strategies were employed to investigate the effects of gene upregulation, as well as upregulation of the PIK3CA signalling pathway, a frequently altered pathway in many cancer types (Jamal-Hanjani et al. 2017; Teixeira et al. 2019). Combining CRISPR gene upregulation to model overexpression, high content imaging (HCS), and automated high-throughput image analysis, a pipeline was developed to screen for CIN and aneuploidy in a normal human cell line, RPE1. This provides a readout of micronuclei and centromere counts. Using this pipeline, upregulation of KIF11 was found to increase the proportion of cells exhibiting micronuclei, and cause significant deviation from the modal centromere count, indicating CIN and aneuploidy. Further investigation of this phenotype revealed that KIF11 upregulation causes spindle pole fragmentation, mitotic catastrophe, and chromosome congression defects. Centric and acentric lagging chromosomes were observed in cells that exhibited both normal and fragmented spindle poles. Mechanistically, KIF11 was shown to generate a force imbalance in the early stages, which could be partially rescued upon upregulation of HSET. MCF10A cell lines expressing PIK3CAH1047R at the endogenous genetic loci as a result of CRISPR genome editing were used to investigate the impact of increased signalling through the PIK3CA pathway on CIN, aneuploidy, and centrosome biology. This showed that PIK3CAH1047R increased the incidence of supernumerary centrosomes, and may play a role in structural CIN, but failed to identify any effect on numerical CIN. Finally, by chemically modulating PIK3CA activity, microtubule dynamics in response to PIK3CA pathway activation and inhibition were investigated
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Dose response of the 16p11.2 distal copy number variant on intracranial volume and basal ganglia.
Carriers of large recurrent copy number variants (CNVs) have a higher risk of developing neurodevelopmental disorders. The 16p11.2 distal CNV predisposes carriers to e.g., autism spectrum disorder and schizophrenia. We compared subcortical brain volumes of 12 16p11.2 distal deletion and 12 duplication carriers to 6882 non-carriers from the large-scale brain Magnetic Resonance Imaging collaboration, ENIGMA-CNV. After stringent CNV calling procedures, and standardized FreeSurfer image analysis, we found negative dose-response associations with copy number on intracranial volume and on regional caudate, pallidum and putamen volumes (β = -0.71 to -1.37; P < 0.0005). In an independent sample, consistent results were obtained, with significant effects in the pallidum (β = -0.95, P = 0.0042). The two data sets combined showed significant negative dose-response for the accumbens, caudate, pallidum, putamen and ICV (P = 0.0032, 8.9 × 10-6, 1.7 × 10-9, 3.5 × 10-12 and 1.0 × 10-4, respectively). Full scale IQ was lower in both deletion and duplication carriers compared to non-carriers. This is the first brain MRI study of the impact of the 16p11.2 distal CNV, and we demonstrate a specific effect on subcortical brain structures, suggesting a neuropathological pattern underlying the neurodevelopmental syndromes
Heritage Quay: What Will You Discover? Transforming the Archives of the University of Huddersfield, Yorkshire, UK
The Heritage Quay project is changing how archive services at the University of Huddersfield are delivered. This article examines how the Staff/Space/Collections dependency model and Customer Service Excellence framework have been used, and what lessons can be drawn for other archives
Reported waterborne outbreaks of gastrointestinal disease in Australia are predominantly associated with recreational exposure
Objective: To examine the frequency and circumstances of reported waterborne outbreaks of gastroenteritis in Australia. Method: Examination of data reported to OzFoodNet between 2001 and 2007. Results: During these seven years, 6,515 gastroenteritis outbreaks were reported to OzFoodNet, most of which were classifed as being transmitted person-to-person or from an unknown source. Fifty-four (0.83%) outbreaks were classifed as either 'waterborne' or 'suspected waterborne', of which 78% (42/54) were attributed to recreational water and 19% (10/54) to drinking water. Of the drinking water outbreaks, implicated pathogens were found on all but one occasion and included Salmonella sp. (fve outbreaks), Campylobacter jejuni (three outbreaks) and Giardia (one outbreak). Conclusions: There have been few waterborne outbreaks detected in Australia, and most of those reported have been associated with recreational exposure. However, there are difficulties in identifying and categorising gastroenteritis outbreaks, as well as in obtaining microbiological and epidemiological evidence, which can result in misclassifcation or underestimation of water-associated events. Implications: Gastroenteritis surveillance data show that, among reported waterassociated gastroenteritis outbreaks in Australia, recreational exposure is currently more common than a drinking water source. However, ongoing surveillance for waterborne outbreaks is important, especially as drought conditions may necessitate replacement of conventional drinking water supplies with alternative water sources, which could incur potential for new health risks
Fine-mapping of the HNF1B multicancer locus identifies candidate variants that mediate endometrial cancer risk.
Common variants in the hepatocyte nuclear factor 1 homeobox B (HNF1B) gene are associated with the risk of Type II diabetes and multiple cancers. Evidence to date indicates that cancer risk may be mediated via genetic or epigenetic effects on HNF1B gene expression. We previously found single-nucleotide polymorphisms (SNPs) at the HNF1B locus to be associated with endometrial cancer, and now report extensive fine-mapping and in silico and laboratory analyses of this locus. Analysis of 1184 genotyped and imputed SNPs in 6608 Caucasian cases and 37 925 controls, and 895 Asian cases and 1968 controls, revealed the best signal of association for SNP rs11263763 (P = 8.4 × 10(-14), odds ratio = 0.86, 95% confidence interval = 0.82-0.89), located within HNF1B intron 1. Haplotype analysis and conditional analyses provide no evidence of further independent endometrial cancer risk variants at this locus. SNP rs11263763 genotype was associated with HNF1B mRNA expression but not with HNF1B methylation in endometrial tumor samples from The Cancer Genome Atlas. Genetic analyses prioritized rs11263763 and four other SNPs in high-to-moderate linkage disequilibrium as the most likely causal SNPs. Three of these SNPs map to the extended HNF1B promoter based on chromatin marks extending from the minimal promoter region. Reporter assays demonstrated that this extended region reduces activity in combination with the minimal HNF1B promoter, and that the minor alleles of rs11263763 or rs8064454 are associated with decreased HNF1B promoter activity. Our findings provide evidence for a single signal associated with endometrial cancer risk at the HNF1B locus, and that risk is likely mediated via altered HNF1B gene expression
Modest increase of KIF11 exposes fragilities in the mitotic spindle causing chromosomal instability
Chromosomal instability (CIN), the process of increased chromosomal alterations, compromises genomic integrity and has profound consequences on human health. Yet, our understanding of the molecular and mechanistic basis of CIN initiation remains limited. We developed a high-throughput, single-cell image-based pipeline employing deep learning and spot counting models to detect CIN by automatically counting chromosomes and micronuclei. To identify CIN-initiating conditions, we used CRISPR activation in human diploid cells to upregulate, at physiologically-relevant levels, 14 genes that are functionally important in cancer. We found that upregulation of CCND1, FOXA1, and NEK2 resulted in pronounced changes in chromosome counts and KIF11 upregulation resulted in micronuclei formation. We identified KIF11-dependent fragilities within the mitotic spindle; increased KIF11 causes centrosome fragmentation, higher microtubule stability, lagging chromosomes or mitotic catastrophe. Our findings demonstrate that even modest average single gene expression changes in a karyotypically stable background are sufficient for initiating CIN by exposing fragilities of the mitotic spindle which can lead to a genomically-diverse cell population
Perspective:Potential impact and therapeutic implications of oncogenic PI3K activation on chromosomal instability
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