Diagnostic significance of DNA and antibodies against capsid antigens of anti-Epstein–Barr virus antibodies levels in blood plasma of nasopharyngeal carcinoma patients from non-endemic region

Abstract

Epstein–Barr virus (EBV), a representative of the herpesvirus family, is the etiological agent for a number of benign and malignant human neoplasms. Among the latter, the nasopharyngeal carcinoma (NPC) occupies a special place. In NPC development EBV plays a key role stimulating the progression of the pathological process from precancerous lesions to the cancer development. For most NPC patients, elevated levels of humoral IgG and IgA antibodies against capsid and early EBV antigens are characteristic and their antibody titers rise to high levels long before the diagnosis of cancer. Using this phenomenon, virus-specific antibodies are used for many years as markers for NPC screening, especially in cases of undiagnosed primary lesion. In recent years, in endemic for NPC regions (South China, South-East Asia) a great attention has been paid to the use of quantitative determination of EBV DNA copies in the blood plasma of patients with NPC as a method of early cancer detection and monitoring. The aim of this study was to compare clinical significance of EBV DNA and humoral antibodies levels in blood plasma of NPC patients in non-endemic region, Russia. The results obtained indicate that both markers DNA / EBV and IgA antibodies against capsid EBV antigens can be successfully used for diagnosis of NPC in non-endemic region. However, in comparison with the virus-specific antibody titers, the viral DNA levels in the patients plasma are more sensitive and specific as NPC marker reflecting the efficacy of the therapy, and the state of remission or relapse.