Expression of Epstein Barr Virus Encoded EBNA1 and LMP1 Oncoproteins in Nasopharyngeal Carcinomas from Northeast India.

BACKGROUND: Nasopharyngeal carcinoma (NPC), a malignancy arising from the epithelial lining of the nasopharynx, is distinct from others cancers in terms of its epidemiologic features. It is rare in most parts of the world except for a few regions with populations of Mongoloid origin. OBJECTIVES: To study the expression pattern of Epstein Barr virus (EBV) encoded oncoproteins EBNA1 and LMP1 in different histological types of NPC and to correlate expression patterns with sex, age and histological types. MATERIALS AND METHODS: A total of 40 formalinfixed, paraffinembedded NPC biopsy samples and tissues from 20 healthy controls were collected to study the expression level of EBNA1 and LMP1 using immunohistochemistry. RESULTS: EBNA1 and LMP1 expression was found in 92.5% and 90% respectively, of the cases and none of the control specimens. The expression patterns of EBNA1 and LMP1 were determined to be statistically significant (p<0.05) when correlated with sex, age and histological distributions. Also immunohistochemistry was found to be a sensitive technique in the detection of EBV. CONCLUSIONS: The study reveals that the potent oncoproteins EBNA1 and LMP1 were over expressed in our population cohort. Our findings are to some extent inconsistent with earlier reports as our population showed a higher expression of both EBNA1 and LMP1 compared to other studies.

Dysfunction of mitochondria due to environmental carcinogens in nasopharyngeal carcinoma in the ethnic group of Northeast Indian population.

Nasopharyngeal carcinoma (NPC) is a rare cancer worldwide, but in India, NPC is uncommon in its subcontinent except in the north-eastern part of the country. NPC is thought to be caused by the combined effects of environmental carcinogens, genetic susceptibility and Epstein-Barr virus (EBV). This is the first study that aimed to examine the selected risk factors, mostly dietary, viral environmental, metabolic gene polymorphisms, mitochondrial DNA (mtDNA) copy number variation and their risk, in subjects who are highly prone to NPC in the ethnic groups of Northeast India, which has included cases, first-degree relatives and controls. The cases and controls were selected from three ethnic groups (Manipuri, Naga and Mizo) of Northeast India with high prevalence of NPC. This case-control family study includes 64 NPC patients, 88 first-degree relatives and 100 controls having no history of cancer. PCR-based detection was done for EBV-latent membrane protein 1 (LMP1) gene and glutathione S-transferase Mu 1 (GSTM1)-glutathione S-transferase theta 1 (GSTT1) polymorphism. A comparative ΔCt method was used for the determination of mtDNA content. An increased risk of 2.00-6.06-folds to NPC was observed with those who intake smoked meat and fish, salted fish and fermented fish; betel nut chewers; tobacco smokers; alcohol drinkers; and those who have kitchen inside the living room, glutathione S-transferase null genotype and EBV infection. The risk of NPC increased in cases with decreased mtDNA copy number (P trend = 0.007). A significant difference between GST null genotypes and EBV infection with mtDNA content was found in the cases (P < 0.0001). The understandings of environment-genetic risk factors and their role in the etiology of NPC are helpful as preventive measures and screening.

Cerebral paragonimiasis mimicking tuberculoma: First case report in India.

An 8-year-old male child of Tuensang District, Nagaland, India, attended Civil Hospital, Tuensang, complaining of cough, fever, headache, and inability to move right arm since one month. On clinical suspicion of tubercular meningitis, anti-tubercular therapy was initiated and the patient was referred to the Naga Hospital Authority. A brain computed tomography scan revealed an isodense area with surrounding edema on the left parietal lobe, which was diagnosed as tuberculoma and the anti-tubercular therapy was continued. As there was no sign of clinical improvement on completion of the three-month-ATD regimen, the patient was investigated for paragonimiasis. Laboratory investigations revealed peripheral blood eosinophilia, raised ESR, Paragonimus egg-positive sputum, and positive Enzyme-linked immunosorbent assay (ELISA) and ID tests for paragonimiasis. The Bacillus Calmette-Guérin (BCG) test and Acid Fast Bacilli (AFB) sputum smears were negative. Chest roentgenogram showed no abnormal findings. A final diagnosis of pulmonary paragonimiasis associated with cerebral paragonimiasis was made. The patient responded to praziquantel therapy. Cerebral paragonimiasis is a serious extrapulmonary form of paragonimiasis, sometimes life-threatening, but curable with praziquantel. It should be included in the differential diagnosis of cerebral granulomatous and other space-occupying lesions.