14 research outputs found

    A global view of the oncogenic landscape in nasopharyngeal carcinoma : an integrated analysis at the genetic and expression levels

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    Previous studies have reported that the tumour cells of nasopharyngeal carcinoma (NPC) exhibit recurrent chromosome abnormalities. These genetic changes are broadly assumed to lead to changes in gene expression which are important for the pathogenesis of this tumour. However, this assumption has yet to be formally tested at a global level. Therefore a genome wide analysis of chromosome copy number and gene expression was performed in tumour cells micro-dissected from the same NPC biopsies. Cellular tumour suppressor and tumour-promoting genes (TSG, TPG) and Epstein-Barr Virus (EBV)-encoded oncogenes were examined. The EBV-encoded genome maintenance protein EBNA1, along with the putative oncogenes LMP1, LMP2 and BARF1 were expressed in the majority of NPCs that were analysed. Significant downregulation of expression in an average of 76 cellular TSGs per tumour was found, whilst a per-tumour average of 88 significantly upregulated, TPGs occurred. The expression of around 60% of putative TPGs and TSGs was both up-and down-regulated in different types of cancer, suggesting that the simplistic classification of genes as TSGs or TPGs may not be entirely appropriate and that the concept of context-dependent onco-suppressors may be more extensive than previously recognised. No significant enrichment of TPGs within regions of frequent genomic gain was seen but TSGs were significantly enriched within regions of frequent genomic loss. It is suggested that loss of the FHIT gene may be a driver of NPC tumourigenesis. Notwithstanding the association of TSGs with regions of genomic loss, on a gene by gene basis and excepting homozygous deletions and high-level amplification, there is very little correlation between chromosomal copy number aberrations and expression levels of TSGs and TPGs in NPC

    Induction of interferon-stimulated genes on the IL-4 response axis by Epstein-Barr virus infected human b cells; relevance to cellular transformation.

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    Epstein-Barr virus (EBV) is an oncogenic virus that is associated with the pathogenesis of several human lymphoid malignancies, including Hodgkin's lymphoma. Infection of normal resting B cells with EBV results in activation to lymphoblasts that are phenotypically similar to those generated by physiological stimulation with CD40L plus IL-4. One important difference is that infection leads to the establishment of permanently growing lymphoblastoid cell lines, whereas CD40L/IL-4 blasts have finite proliferation lifespans. To identify early events which might later determine why EBV infected blasts go on to establish transformed cell lines, we performed global transcriptome analyses on resting B cells and on EBV and CD40L/IL-4 blasts after 7 days culture. As anticipated there was considerable overlap in the transcriptomes of the two types of lymphoblasts when compared to the original resting B cells, reflecting common changes associated with lymphocyte activation and proliferation. Of interest to us was a subset of 255 genes that were differentially expressed between EBV and CD40L/IL-4 blasts. Genes which were more highly expressed in EBV blasts were substantially and significantly enriched for a set of interferon-stimulated genes which on further in silico analyses were found to be repressed by IL-4 in other cell contexts and to be up-regulated in micro-dissected malignant cells from Hodgkin's lymphoma biopsies when compared to their normal germinal center cell counterparts. We hypothesized that EBV and IL-4 were targeting and discordantly regulating a common set of genes. This was supported experimentally in our B cell model where IL-4 stimulation partially reversed transcriptional changes which follow EBV infection and it impaired the efficiency of EBV-induced B cell transformation. Taken together, these data suggest that the discordant regulation of interferon and IL-4 pathway genes by EBV that occurs early following infection of B cells has relevance to the development or maintenance of an EBV-associated malignancy

    Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study

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    Purpose: Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom. Methods: Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded. Results: The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8–4.6) in CFS 4 vs 1–3; OR 12.4 (6.2–24.5) in CFS 8 vs 1–3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3–1.9) in CFS 4 compared to 0.2 (0.1–0.7) in CFS 8). These risks were both independent of age and dementia. Conclusion: We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes

    Cigarette smoking is an independent risk factor for cervical intraepithelial neoplasia in young women : a longitudinal study

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    Repeated measurements of smoking, cervical human papillomavirus (HPV) status and sexual behaviour were used to measure the risk of high-grade cervical intraepithelial neoplasia (CIN) in relation to changes in smoking and cervical HPV status, and to explore the impact of smoking on the acquisition and duration of incident cervical HPV infection. Included in this longitudinal analysis are 1485 women aged 15–19 years: 1075 were HPV-negative and cytologically normal at recruitment; 410 were HPV-positive, cytologically abnormal or both, at this time. Women re-attended every 6 months, when samples were taken for cytological and virological examination. Current smoking intensity was associated with an increased risk of high-grade CIN, after controlling for cervical HPV status (compared to non-smokers, hazards ratio (HR) for 10 or more cigarettes per day = 2.21, 95% confidence interval (CI) 1.19–4.12, p-trend = 0.008). In women who were HPV-negative and cytologically normal at recruitment, current smoking was not significantly associated with the risk of acquiring a cervical HPV infection, after controlling for life-time number of partners and age of oldest partner (HR = 1.13, 95% CI 0.90–1.41); nor did it prolong the length of time during which HPV could be detected (HR = 1.03, 95% CI 0.78–1.34). Current smoking intensity is an independent risk factor for high-grade CIN in young women, after controlling for cervical HPV infection

    Disruption of the E2 Gene is a common and early event in the natural history of cervical human papillomavirus infection : a longitudinal cohort study

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    Integration of high-risk human papillomavirus (HPV) types into the host-cell genome disrupts the HPV regulatory E2 protein, resulting in a loss of negative feedback control of viral oncogene expression; this disruption has been considered a critical event in the pathogenesis of cervical neoplasia, and a potential biomarker of progressive disease. However, using serial samples taken from a cohort of young women who were recruited soon after they first had sexual intercourse, we show that disruption of the E2 gene is a common and early event in the natural history of incident cervical HPV infections. The E2 gene was significantly more likely to be disrupted in women who tested positive for HPV18 in their baseline sample than in those who tested positive for HPV16 [26% versus 58%; relative risk, 2.26; 95% confidence interval (CI), 1.38–3.71; χ2, 9.23; 1 degree of freedom (df); P = 0.002]. Among women with an intact E2 gene in their baseline sample, the median time to first detection of E2 disruption was also shorter for those who tested positive for HPV18 than HPV16 (5.7 versus 10.9 months; hazards ratio, 1.93; 95% CI, 0.84–4.44; χ2, 2.49; 1 df; P = 0.11). This tendency for HPV18 to integrate early, coupled with the substantial reduction in viral load in HPV18-positive samples in which E2 is disrupted, may explain why HPV18-associated disease is often reported to be characterized by minor cytologic changes, which underestimate the severity of the underlying histologic abnormality

    Association of an intact <i>E2</i> gene with higher HPV viral load, higher viral oncogene expression, and improved clinical outcome in HPV16 positive head and neck squamous cell carcinoma

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    <div><p>To assess the relationship of <i>E2</i> gene disruption with viral gene expression and clinical outcome in human papillomavirus (HPV) positive head and neck squamous cell carcinoma, we evaluated 31 oropharyngeal and 17 non-oropharyngeal HPV16 positive carcinomas using two PCR-based methods to test for disruption of <i>E2</i>, followed by Sanger sequencing. Expression of HPV16 <i>E6</i>, <i>E7</i> and <i>E2</i> transcripts, along with cellular <i>ARF</i> and <i>INK4A</i>, were also assessed by RT-qPCR. Associations between <i>E2</i> disruption, E2/E6/E7 expression, and clinical outcome were evaluated by Kaplan-Meier analysis for loco-regional recurrence and disease-specific survival. The majority (n = 21, 68%) of HPV16 positive oropharyngeal carcinomas had an intact <i>E2</i> gene, whereas the majority of HPV16 positive non-oropharyngeal carcinomas (n = 10, 59%) had a disrupted <i>E2</i> gene. Three of the oropharyngeal tumors and two of the non-oropharyngeal tumors had deletions within <i>E2</i>. Detection of an intact <i>E2</i> gene was associated with a higher DNA viral load and increased <i>E2/E6/E7</i>, <i>ARF</i> and <i>INK4A</i> expression in oropharyngeal tumors. Oropharyngeal carcinomas with an intact <i>E2</i> had a lower risk of loco-regional recurrence (log-rank p = 0.04) and improved disease-specific survival (p = 0.03) compared to tumors with disrupted <i>E2</i>. In addition, high E7 expression was associated with lower risk of loco-regional recurrence (p = 0.004) as was high E6 expression (p = 0.006). In summary, an intact <i>E2</i> gene is more common in HPV16 positive oropharyngeal than non-oropharyngeal carcinomas; the presence of an intact <i>E2</i> gene is associated with higher HPV viral load, higher viral oncogene expression, and improved clinical outcome compared to patients with a disrupted <i>E2</i> gene in oropharyngeal cancer.</p></div

    Positions of HPV16 E2 primers along the HPV16 E2 gene.

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    <p>The HPV16 genome encompassing the <i>E2</i> gene region shown in gray. Primer locations of the <i>E2</i> disruption assay and the <i>E2</i> full gene primer set are shown above and numbered according to nucleotides on the whole genome. Overlapping primer design is illustrated below along with product size primer set.</p
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