Epstein–Barr virus: novel patented therapeutics

Carcinogenic viruses and solid cancers without sufficient evidence of causal association

Viral infections are important risk factors for tumor development in humans. Selected types of cancers, either lymphomas or carcinomas, for which there is sufficient evidence in humans of a causal association with specific viruses, have been identified. Experimental and clinical data on the possible association of other tumor types and carcinogenic viruses are presently controversial. In this article, we review the current evidence on the relationship between breast, colorectal and lung cancers and carcinogenic viruses. The majority of the publications reviewed do not provide definitive evidence that the viruses studied are associated with breast, colon and lung cancers. However, since this association may be clinically relevant for some tumor subtypes (i.e., lung cancer and papillomaviruses), there is an urgent need for further investigation on this topic. Using innovative laboratory techniques for viral detection on well-defined tumor types, National and International networks against cancer should encourage and organize concerted research programs on viruses and solid cancer association.

Safety of in vitro amplified HLA-haploidentical donor immune cell infusions for childhood malignancies

In vitro amplified human leukocyte antigen (HLA)-haploidentical donor immune cell infusion (HDICI) is not commonly used in children. Therefore, our study sought to evaluate its safety for treating childhood malignancies. Between September 2011 and September 2012, 12 patients with childhood malignancies underwent HDICI in Sun Yat-sen University Cancer Center. The median patient age was 5.1 years (range, 1.7-8.4 years). Of the 12 patients, 9 had high-risk neuroblastoma (NB) [7 showed complete response (CR), 1 showed partial response (PR), and 1 had progressive disease (PD) after multi-modal therapies], and 3 had Epstein-Barr virus (EBV)-positive lymphoproliferative disease (EBV-LPD). The 12 patients underwent a total of 92 HDICIs at a mean dose of 1.6×10⁸ immune cells/kg body weight: 71 infusions with natural killer (NK) cells, 8 with cytokine-induced killer (CIK) cells, and 13 with cascade primed immune cells (CAPRIs); 83 infusions with immune cells from the mothers, whereas 9 with cells from the fathers. Twenty cases (21.7%) of fever, including 6 cases (6.5%) accompanied with chills and 1 (1.1%) with febrile convulsion, occurred during infusions and were alleviated after symptomatic treatments. Five cases (5.4%) of mild emotion changes were reported. No other adverse events occurred during and after the completion of HDIDIs. Neither acute nor chronic graft versus host disease (GVHD) was observed following HDICIs. After a median of 5.0 months (range, 1.0-11.5 months) of follow-up, the 2 NB patients with PR and PD developed PD during HDICIs. Of the other 7 NB patients in CR, 2 relapsed in the sixth month of HDICIs, and 5 maintained CR with disease-free survival (DFS) ranging from 4.5 to 11.5 months (median, 7.2 months). One EBV-LPD patient achieved PR, whereas 2 had stable disease (SD). Our results show that HDICI is a safe immunotherapy for childhood malignancies, thus warranting further studies.

Resveratrol inhibits Epstein Barr Virus lytic cycle in Burkitt's lymphoma cells by affecting multiple molecular targets

Resveratrol (RV), a polyphenolic natural product present in many plants and fruits, exhibits anti-inflammatory, cardio-protective and anti-proliferative properties. Moreover, RV affects a wide variety of viruses including members of the Herpesviridae family, retroviruses, influenza A virus and polyomavirus by altering cellular pathways that affect viral replication itself. Epstein Barr Virus (EBV), the causative agent of infectious mononucleosis, is associated with different proliferative diseases in which it establishes a latent and/or a lytic infection. In this study, we examined the antiviral activity of RV against the EBV replicative cycle and investigated the molecular targets possibly involved. In a cellular context that allows in vitro EBV activation and lytic cycle progression through mechanisms closely resembling those that in vivo initiate and enable productive infection, we found that RV inhibited EBV lytic genes expression and the production of viral particles in a dose-dependent manner. We demonstrated that RV inhibited protein synthesis, decreased reactive oxygen species (ROS) levels, and suppressed the EBV-induced activation of the redox-sensitive transcription factors NF-kB and AP-1. Further insights into the signaling pathways and molecular targets modulated by RV may provide the basis for exploiting the antiviral activity of this natural product on EBV replication.

Current diagnosis and management of infectious mononucleosis

PURPOSE OF REVIEW

Infectious mononucleosis is a common, usually self-limited disease. However, infectious mononucleosis may present with severe manifestations. Complications may also occur. Consequently, diagnostic and treatment issues regarding infectious mononucleosis are of major importance.

RECENT FINDINGS

In this review, we focus on the evaluation of articles providing diagnosis and treatment data for infectious mononucleosis, published during the past 2 years. Twelve studies, deriving from extended search in PubMed, were included. Nine studies provided diagnosis data. The evaluated diagnostic methods were real-time PCR (RT-PCR), IgM/IgG antibodies measured with different assays [measurement of Epstein-Barr virus viral load (EBV-VL) in peripheral blood, neutrophil/lymphocyte/monocyte counts, C-reactive protein values, and monospot test]. The sensitivities reported for RT-PCR were high. The available treatment data were scarce (three studies). Two of them suggested that antivirals (mainly acyclovir and valacyclovir) may have a role in the treatment of infectious mononucleosis with complications, whereas the remaining study presented novel potential therapeutic patents including 5-substituted uracyle, azacytosine derivatives, and peptides inhibiting EBV-mediated membrane fusion.

SUMMARY

RT-PCR and measurement of EBV-VL may provide useful tools for the early diagnosis of infectious mononucleosis in cases with inconclusive serological results. Antiviral agents may provide a useful treatment option in patients with severe infectious mononucleosis.