Analysis of Epstein-Barr Virus (EBV) and PD-L1 Expression in Nasopharyngeal Carcinoma Patients in a Non-Endemic Region

Mechanisms of T cell evasion by Epstein-Barr virus and implications for tumor survival

Epstein-Barr virus (EBV) is a prevalent oncogenic virus estimated to infect greater than 90% of the world's population. Following initial infection, it establishes latency in host B cells. EBV has developed a multitude of techniques to avoid detection by the host immune system and establish lifelong infection. T cells, as important contributors to cell-mediated immunity, make an attractive target for these immunoevasive strategies. Indeed, EBV has evolved numerous mechanisms to modulate T cell responses. For example, it can augment expression of programmed cell death ligand-1 (PD-L1), which inhibits T cell function, and downregulates the interferon response, which has a strong impact on T cell regulation. It also modulates interleukin secretion and can influence major histocompatibility complex (MHC) expression and presentation. In addition to facilitating persistent EBV infection, these immunoregulatory mechanisms have significant implications for evasion of the immune response by tumor cells. This review dissects the mechanisms through which EBV avoids detection by host T cells and discusses how these mechanisms play into tumor survival. It concludes with an overview of cancer treatments targeting T cells in the setting of EBV-associated malignancy.

Head and neck cancer burden in India: an analysis from published data of 37 population-based cancer registries

Head and neck cancer (HNC) is a major public health problem in India. This article presents the HNC burden in different regions of India. The published population-based cancer registries (PBCRs) data from the National Cancer Registry Programme, Bengaluru, and the Tata Memorial Centre, Mumbai, India, were utilised. The 37 PBCRs were divided into six regions including central, east, north, northeast, west and south. The age-standardised incidence rate of HNC was 25.9 (95% CI 25.7-26.1) and 8.0 (95% CI 7.9-8.1) per 100,000 population, respectively, in males and females. HNC accounted for about 26% of all cancer cases in males and 8% in females. The risk of developing HNC was 1 in 33 for males and 1 in 107 for females. The northeastern registries reported the highest incidence rate 31.7 per 100,000 population in males followed by northern (28.5), central (28.3), western (24.4), southern (23.9) and eastern (18.3). In females, the incidence was in the range of 6.2-10.1 per 100,000 population. For all PBCRs together, the HNC burden was two to three times higher in the age group 60+ as compared to 20-39 years. The HNC burden in India is higher than in the USA, UK, Australia, Africa and Brazil. The PBCRs from the south-east Asia region such as the Colombo district, Sri Lanka, as well as Siraha, Saptari, Dhanusha and Mohattari - Nepal have also reported a high burden of HNC. All regions reported mouth as a leading cancer site followed by tongue, larynx, hypopharynx and tonsil except the northeastern region registries where hypopharynx was the top leading cancer. The burden of other sites of HNC is low. Raising awareness of the disease and associated risk factors, providing early detection services, as well as easy access to diagnosis and treatment are required. The government should focus on building the infrastructure and capacity building to control this disease.

Updates on Epstein-Barr Virus (EBV)-Associated Nasopharyngeal Carcinoma: Emphasis on the Latent Gene Products of EBV

Nasopharyngeal carcinoma (NPC) is an uncommon type of malignancy/cancer worldwide. However, NPC is an endemic disease in southeast Asia and southern China and the reasons behind the underlying for such changes are unclear. Even though the Epstein-Barr infection (EBV) has been suggested as an important reason for undistinguishable NPC, the EBV itself is not adequate to source this type of cancer. The risk factors, for example, genetic susceptibility, and environmental factors might be associated with EBV to undertake a part in the NPC carcinogenesis. Normal healthy people have a memory B cell pool where the EBV persists, and any disturbance of this connection leads to virus-associated B cell malignancies. Less is known about the relationship between EBV and epithelial cell tumors, especially the EBV-associated nasopharyngeal carcinoma (EBVaNPC) and EBV-associated gastric carcinoma (EBVaGC). Currently, it is believed that premalignant genetic changes in epithelial cells contribute to the aberrant establishment of viral latency in these tumors. The early and late phases of NPC patients' survival rates vary significantly. The presence of EBV in all tumor cells presents prospects for the development of innovative therapeutic and diagnostic techniques, despite the fact that the virus's exact involvement in the carcinogenic process is presently not very well known. EBV research continues to shed light on the carcinogenic process, which is important for a more comprehensive knowledge of tumor etiology and the development of targeted cancer therapeutics. In order to screen for NPC, EBV-related biomarkers have been widely used in a few high-incidence locations because of their close associations with the risks of NPC. The current review highlights the scientific importance of EBV and its possible association with NPC.