EBV

Objectives Plasmablastic lymphoma (PBL) is a clinically aggressive lymphoma which has a predilection for extranodal sites and is frequently HIV-associated. The incidence of non-Hodgkin lymphoma is thought to be reduced by widescale antiretroviral therapy (ART) coverage, but the literature is sparse as regards the impact of ART on the incidence of PBL and its outcomes in South Africa (SA). This study aimed to compare factors of interest in cases of PBL diagnosed before and after the widespread availability of ART in Johannesburg, SA. Methods All cases of PBL diagnosed in the state sector hospitals of Johannesburg in 2007 and 2017 (before and after the widespread availability of ART, respectively) were extracted from the laboratory information system, and factors of interest compared. Results The majority (> 95%) of cases of PBL were seen among people with HIV infection (PWH) at both time-points, and the proportion of patients on ART and with virological suppression (VS) increased significantly in 2017. However, the number of cases of PBL did not differ significantly between the two years assessed, comprising 46/397 (11.6%) and 53/582 (9.6%) of all lymphomas in 2007 and 2017, respectively (P = 0.23). Ongoing risk for PBL among PWH with virological control and immunological recovery was evident in 2017, as 18.9% of the patients had both VS and CD4 counts > 200 cells/mu L at diagnosis. Inferior survival times were associated with elevated lactate dehydrogenase (LDH) levels and Epstein Barr virus (EBV) negativity, but were not influenced by the presence of AIDS, ART or VS. EBV negativity was significantly associated with VS, and appeared to flag a particularly aggressive form of the disease. Conclusions Widescale ART coverage has not reduced the incidence of PBL in Johannesburg, and an ongoing risk for this disease among PWH with adequate virological control and immunological recovery persists.

Recent reports have pointed to the link between persistent inflammation, oxidative stress, and carcinogenesis; however most of the studies concerning the role of viruses in head and neck cancer (HNC) are focused mainly on one type of virus. Our present study aimed to study the relationship between Epstein-Barr virus/human papilloma virus (EBV/HPV) coinfection and glutathione peroxidase (GPx) and superoxide dismutase (SOD) level in oropharyngeal cancer. Fresh-frozen tumor tissue samples were collected from 128 patients with oropharyngeal cancer infected with EBV or HPV or with EBV/HPV coinfection. After DNA extraction, EBV and HPV DNA was detected using a polymerase chain reaction (PCR) assay. GPx and SOD activity was determined in homogenates of cancer tissue using diagnostic kits produced by Randox Laboratories. Both GPx and SOD activity was statistically lower in patients with EBV/HPV coinfection than in a single EBV or HPV infection. Analysis of GPx and SOD activity in relation to histological grading and tumor, node (TN) classification revealed that in poorly-differentiated tumors, the level of antioxidant enzymes was lower compared with well-differentiated lesions and in cases with greater tumor dimensions and lymph-node involvement, both GPx and SOD activity was decreased. Further studies are necessary to clarify the influence of interplay between EBV, HPV, and oxidative stress on malignant transformation of upper aerodigestive tract epithelial cells.