Nasopharyngeal carcinoma

Brennan, Bernadette

doi:10.1186/1750-1172-1-23

Cited by 224 publications

(208 citation statements)

References 25 publications

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“…Carcinogens, including nitrosamines in salted fish, have been reported to aggravate NPC (70,71), and nitrosamines were found to activate PKA (72), probably inducing LMP1 in NPC. Other factors, such as growth factors or cytokines, are also feasible candidate modulators of PKA activity.…”

Section: Discussionmentioning

confidence: 99%

Induction of Epstein-Barr Virus Oncoprotein LMP1 by Transcription Factors AP-2 and Early B Cell Factor

Murata

Noda

Narita

et al. 2016

J Virol

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Latent membrane protein 1 (LMP1) is a major oncogene essential for primary B cell transformation by Epstein-Barr virus (EBV).Previous studies suggested that some transcription factors, such as PU.1, RBP-J, NF-B, and STAT, are involved in this expression, but the underlying mechanism is unclear. Here, we identified binding sites for PAX5, AP-2, and EBF in the proximal LMP1 promoter (ED-L1p). We first confirmed the significance of PU.1 and POU domain transcription factor binding for activation of the promoter in latency III. We then focused on the transcription factors AP-2 and early B cell factor (EBF). Interestingly, among the three AP-2-binding sites in the LMP1 promoter, two motifs were also bound by EBF. Overexpression, knockdown, and mutagenesis in the context of the viral genome indicated that AP-2 plays an important role in LMP1 expression in latency II in epithelial cells. In latency III B cells, on the other hand, the B cell-specific transcription factor EBF binds to the ED-L1p and activates LMP1 transcription from the promoter. IMPORTANCE Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) is crucial for B cell transformation and oncogenesis of other EBVrelated malignancies, such as nasopharyngeal carcinoma and T/NK lymphoma.Its expression is largely dependent on the cell type or condition, and some transcription factors have been implicated in its regulation. However, these previous reports evaluated the significance of specific factors mostly by reporter assay. In this study, we prepared point-mutated EBV at the binding sites of such transcription factors and confirmed the importance of AP-2, EBF, PU.1, and POU domain factors. Our results will provide insight into the transcriptional regulation of the major oncogene LMP1. The Epstein-Barr virus (EBV) is a human gammaherpesvirus that mainly infects and establishes latent infection in B lymphocytes, but it can also infect other types of cells, including NK, T, and epithelial cells. EBV infection has been implicated as a causal factor in a variety of malignancies, and the expression pattern of viral latent genes varies depending on the tissue of origin and the state of the tumors. Neoplasms such as Burkitt lymphomas or gastric carcinomas express only EBV-encoded small RNA (EBER) and EBV nuclear antigen 1 (EBNA1) (type I latency), whereas some Hodgkin lymphomas, nasopharyngeal carcinomas (NPC), and NK/T lymphomas express EBER, EBNA1, latent membrane protein 1 (LMP1), and LMP2 genes (type II latency). In addition to the type II genes, EBNA2, EBNA3, and EBNA-LP are also expressed in immunosuppression-related lymphomas or lymphoblastoid cell lines (LCLs; type III latency). LMP1 constitutively activates cellular signaling through NF-B, mitogen-activated protein, JAK/STAT, and AKT and is believed to be a major oncogene encoded by EBV (1-11).Two promoters regulate LMP1 gene transcription, with mechanisms that differ between type II and type III infection. In latency III in B lymphocytes, LMP1 transcription from the proximal ED-L1 promoter is acti...

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Section: Discussionmentioning

confidence: 99%

Induction of Epstein-Barr Virus Oncoprotein LMP1 by Transcription Factors AP-2 and Early B Cell Factor

Murata

Noda

Narita

et al. 2016

J Virol

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“…1 The development of a second primary malignant tumor in subjects with a previous history of nasopharyngeal carcinoma is unusual. 2 The most common second primary cancer which can occur is sarcoma (0.14%), followed by leukemia and squamous cell carcinoma.…”

Section: …………………………………………………………………………………………………… Introduction:-mentioning

confidence: 99%

“…Discussion:-Nasopharyngeal carcinoma (NPC) is a tumor arising from the epithelial cells that line the nasopharynx. 1 NPC is prevalent in China, Southeast Asia, Mediterranean basin and Alaska and an incidence of 2 per million has been reported in these regions. 1 In India, the incidence is 0.9 per million, 1 except in the Northeastern region (1.82%).…”

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confidence: 99%

“…1 NPC is prevalent in China, Southeast Asia, Mediterranean basin and Alaska and an incidence of 2 per million has been reported in these regions. 1 In India, the incidence is 0.9 per million, 1 except in the Northeastern region (1.82%). 4 A number of etiologic factors such as race, genetics, environmental factors namely nitrosamines present in preserved /salted and fermented food, occupational exposure to wood dust, formaldehyde, chemical fumes and Epstein-Barr virus (EBV) have been implicated in the etiology of NPC.…”

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confidence: 99%

“…It has an irregular or spherical shape with sharp edges. 1 The tumour most frequently metastasizes to bone (70-80%), followed by viscera (30%) and at lower rates to extracervical lymph-nodes (18%) such as axillary, mediastinal, pelvic, or inguinal. 6 The mainstay of management for stages I and II is radiotherapy (RT), patients with stage III have been treated with concurrent chemotherapy and radiotherapy and stage 1V with palliative chemotherapy.…”

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Second Primary Tumor of the Tongue – A Case Report.

Iyengar¹,

Patil²,

Fatima³

et al. 2017

IJAR

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Nasopharyngeal carcinoma (NPC) is a tumor arising from the epithelial cells lining the nasopharynx. The development of a second primary tumor in subjects with a previous history of nasopharyngeal carcinoma is a rare event. The most common second primary cancer which can occur is sarcoma (0.14%), followed by leukemia and squamous cell carcinoma. In the present case, a second primary tumor (squamous cell carcinoma) on right lateral border of tongue in a 64 year old male patient treated for nasopharyngeal carcinoma with radiotherapy and chemotherapy 5 years previously is discussed. …………………………………………………………………………………………………….... Introduction:-Nasopharyngeal carcinoma (NPC) is a tumor arising from the epithelial cells lining the nasopharynx. 1 The development of a second primary malignant tumor in subjects with a previous history of nasopharyngeal carcinoma is unusual. 2 The most common second primary cancer which can occur is sarcoma (0.14%), followed by leukemia and squamous cell carcinoma. 2 These second primaries can occur in the lung, oesophagus and also in the head and neck region. 2 In the oro-pharyngeal region, tongue is a common site of involvement (1.8%). 2 The proposed pathogenic mechanisms of the development of second primary cancers include radiotherapy, field cancerization and common risk factors. 2 The present case is of second primary tumor (squamous cell carcinoma) on right lateral border of tongue in a 64 year old male patient treated for nasopharyngeal carcinoma.Case Report:-A 64 year old male visited the department of Oral medicine and Radiology with a complaint of frequent biting of the right side of the tongue while eating and talking since 6 months. He had visited several dental practitioners for the management of the same and coronoplasty of maxillary and mandibular posterior teeth was performed. However, there was no relief. He had visited an oncology centre 2 days prior to visiting the present institution for a PET-CT scan. The scan was advised as a part of the follow-up protocol for treated nasopharyngeal carcinoma that was diagnosed 5 years ago. Patient had undergone radiotherapy and chemotherapy for the same. The treatment was completed 4 years ago. An increased FDG uptake was noted on PET-CT with regard to the right lateral aspect of tongue.He was advised partial glossectomy by the oncosurgeon for the same.

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