Epstein-Barr virus (EBV), discovered > 40 years ago from a Burkitt's lymphoma biopsy, was the first virus to be directly associated with human cancer. EBV has two distinct life cycles in the human host; a lytic form of infection that produces new infectious virions, and a latent form of infection that allows the virus to persist in a dormant state for the lifetime of the host. EBV has evolved a life cycle that mimics the natural differentiation pathway of antigen-activated B cells, giving the virus access to its site of latent infection, the resting memory B cell. By steering infected cells through the various stages of lymphocyte differentiation, EBV is able to enter a cell type suitable for long-term latent persistence and periodic reactivation. However, its presence in various stages of B-cell development, and its ability to infect certain epithelial cells, can have pathogenic consequences, and can contribute to the development of a diverse group of lymphomas and carcinomas. The presence of EBV in the tumour cells of EBV-associated cancers might provide a basis for specific therapy. This article focuses on the contributions that the virus may play in different types of human cancer, particularly Burkitt's lymphoma, Hodgkin's lymphoma, lymphomas and lymphoproliferative diseases in the immunocompromised, and nasopharyngeal and gastric carcinoma.
Novel Epstein-Barr Virus (EBV) strains with deletion of either EBER1 or EBER2 and corresponding revertant viruses were constructed and used to infect B lymphocytes to make lymphoblastoid cell lines (LCLs). The LCLs were used in microarray expression profiling to identify genes whose expression correlates with the presence of EBER1 or EBER2. Functions of regulated genes identified in the microarray analysis include membrane signaling, regulation of apoptosis, and the interferon/antiviral response. Although most emphasis has previously been given to EBER1 because it is more abundant than EBER2, the differences in cell gene expression were greater with EBER2 deletion. In this system, deletion of EBER1 or EBER2 had little effect on the EBV transformation frequency of primary B cells or the growth of the resulting LCLs. Using the recombinant viruses and novel EBER expression vectors, the nuclear redistribution of rpL22 protein by EBER1 in 293 cells was confirmed, but in LCLs almost all of the cells had a predominantly cytoplasmic expression of this ribosomal protein, which was not detectably changed by EBER1. The changes in LCL gene expression identified here will provide a basis for identifying the mechanisms of action of EBER RNAs.
SURG±Adj and CRT had similar survival. Severe comorbidity was associated with selection bias to RT and reduced 5-year CSS. Comorbidity is a key prognostic variable and should be considered in the interpretation of treatment outcomes.
Squamous cell carcinomas of the hypopharynx (HPSCC) and oropharynx (OPSCC) have markedly different patient outcomes. Differences in HPV prevalence between these two patient groups may account for some of this difference, but other molecular markers of prognosis or pathological phenotype have not been established. Copy number gain of oncogenes is a well-established molecular change contributing to HNSCC development. Quantitative PCR was used to explore copy number gains of specific genes (3q -PIK3CA, TP63; 11q13.3 -CCND1, ANO1) in tumour DNA recovered from HPSCC (n=48) and OPSCC (n=52) patients. Associations between copy number gain, patient demographics, HPV/p16INK4a status and pathological stage were examined.HPV/p16 prevalence in HPSCC and OPSCC groups was 2.1% and 46.0% respectively. HPSCCs had frequent gains of CCND1 (56.3%) and ANO1 (56.3%) but few gains of PIK3CA (6.3%). By contrast, OPSCCs had significantly fewer CCND1 (23.1%) and ANO1 (17.3%) gains, and significantly more PIK3CA (26.9%) gains. A mutually exclusive relationship between HPV/p16 and 11q13.3 gains was observed in OPSCCs, while PIK3CA and TP63 gains were similar across HPVassociated and smoking/alcohol-associated patients. ANO1 gain was significantly linked to tumour pathology in HPSCC, associating with nodal metastasis and smaller and less invasive tumours at presentation (p=0.010). Our results provide a convincing link between a specific molecular change and disease phenotype that appears unique to our HPSCC population, supporting a model of 11q13.3 in promoting metastatic disease progression in HNSCC, and suggest a role for ANO1 as a molecular marker of metastatic disease. words
Neurodegenerative diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), and amyotrophic lateral sclerosis (ALS) are traditionally considered strictly neurological disorders. However, clinical presentation is not restricted to neurological systems, and non-central nervous system (CNS) manifestations, particularly gastrointestinal (GI) symptoms, are common. Our objective was to understand the systemic distribution of pathology in archived non-CNS tissues, taken as part of routine clinical practice during life from people with ALS. We examined tissue from 13 people who went on to develop ALS; including sporadic ALS (n = 12) and C9orf72 hexanucleotide repeat expansion (n = 1). The tissue cohort consisted of 68 formalin-fixed paraffin embedded samples from 21 surgical cases (some patients having more than one case over their lifetimes), from 8 organ systems, which we examined for evidence of phosphorylated TDP-43 (pTDP-43) pathology. We identified pTDP-43 aggregates in multiple cell types of the GI tract, including macrophages and dendritic cells within the lamina propria; as well as ganglion/ neuronal and glial cells of the myenteric plexus. Aggregates were also noted within lymph node parenchyma, blood vessel endothelial cells, and chondrocytes. We note that in all cases with non-CNS pTDP-43 pathology, aggregates were present prior to ALS diagnosis and in some instances preceded neurological symptom onset by more than 10 years. These data imply that patients with microscopically unexplained non-CNS symptoms could have occult protein aggregation that could be detected many years prior to neurological involvement.
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