Quantitative analysis of circulating cell-free Epstein-Barr virus (EBV) DNA levels in patients with EBV-associated lymphoid malignancies

Abstract

Cell-free Epstein-Barr virus (EBV) DNA has recently been detected in the plasma and serum of patients with Hodgkin's disease, post-transplant lymphoproliferative disease (PTLD) and acquired immunodeficiency syndrome-related lymphoma. However, no data are available on the temporal variation of plasma/serum EBV DNA levels in patients with EBV-associated lymphoid malignancies during the course of therapy. Using a real-time quantitative polymerase chain reaction assay, we studied the plasma EBV DNA levels in 13 patients with EBV-associated lymphoid malignancies (six patients with Hodgkin's disease, four with nasal natural killer/T-cell lymphoma, two cases of PTLD and one patient with Burkitt's lymphoma) at presentation and during therapy. Plasma EBV DNA was detected in 12 of the 13 patients (median 2,266 copies/ml; interquartile range 181-8,379 copies/ml), but not in any of 35 healthy control subjects (P < 0.0001). The EBV status in tumour cells was also examined in 12 of these patients using in situ hybridization for EBV-encoded small RNAs (EBERs). EBER positivity was observed in 11 patients, all of whom had EBV DNA detectable in plasma. The one patient who had no detectable plasma EBV DNA was also negative for EBERs in tumour tissue. Serial measurements of plasma EBV DNA levels were performed in nine of the patients during the course of therapy. All patients who responded to therapy demonstrated a significant reduction of plasma EBV DNA to low or undetectable levels, whereas in two patients with ineffective therapy, disease progression was associated with a rapid increase in plasma EBV DNA levels. We concluded that plasma EBV DNA is detectable in a wide range of EBV-associated lymphoid malignancies. As plasma EBV DNA levels correlate well with the therapeutic response, such analysis may be a valuable tool for monitoring clinical progress.

Profiling of Epstein‐Barr virus‐encoded microRNAs in nasopharyngeal carcinoma reveals potential biomarkers and oncomirs

“…Identifying EBV microRNAs more exclusive to NPC may also aid in screening against other EBV-associated malignancies that demonstrate elevated levels of circulating EBV DNA. 46,47 Overall, the preferential release of certain EBV microRNAs into the serum of NPC patients at least warrants further study into its potential clinical application.…”

Measuring Epstein–Barr virus (EBV) load: the significance and application for each EBV‐associated disease

“…Indeed, cell-free EBV DNA is detected in the serum of most patients with EBV-associated Hodgkin's lymphoma [42]. EBV load in the serum or plasma is correlated with therapeutic responses [86], and EBV positivity in post-treatment samples indicates a poor prognosis [42]. Thus, serum and plasma are optimal samples to monitor Hodgkin's lymphoma (Table 3).…”

(-)-Epigallocatechin‑3‑gallate inhibition of Epstein‑Barr virus spontaneous lytic infection involves downregulation of latent membrane protein 1

“…Notably, studies suggest that EBV reactivation into a lytic cycle may contribute to the pathogenesis of malignancies (7,8). EBV lytic infection in vivo has been identified by elevated antibody titers against EBV lytic antigens and by increased viral DNA load in the serum/plasma, and these observations correspond with advanced cancer stages, poor prognosis or tumor recurrence following therapy (9,10). Additionally, serological studies have indicated that EBV lytic infection may occur months or years prior to a clinical diagnosis of NPC, HD or Burkitt's lymphoma, which suggests EBV lytic infection may be a risk factor for cancer development (11)(12)(13).…”