A Comprehensive Analysis of the Cellular and EBV-Specific MicroRNAome in Primary CNS PTLD Identifies Different Patterns Among EBV-Associated Tumors

Abstract

Primary central nervous system (pCNS) posttransplant lymphoproliferative disorder (PTLD) is a complication of solid organ transplantation characterized by poor outcome. In contrast to systemic PTLD, Epstein-Barr virus (EBV)-association of pCNS PTLD is almost universal, yet viral and cellular data are limited. To identify differences in the pattern of EBV-association of pCNS and systemic PTLD, we analyzed the expression of latent and lytic EBV transcripts and the viral and cellular microRNAome in nine pCNS (eight EBV-associated) and in 16 systemic PTLD samples (eight EBV-associated). Notably although 15/16 EBV-associated samples exhibited a viral type III latency pattern, lytic transcripts were also strongly expressed. Members of the ebv-miR-BHRF1 and ebv-miR-BART clusters were expressed in virtually all EBV-associated PTLD samples. There were 28 cellular microRNAs differentially expressed between systemic and pCNS PTLD. pCNS PTLD expressed lower hsa-miR-199a-5p/3p and hsa-miR-143/145 (implicated in nuclear factor kappa beta and c-myc signaling) as compared to systemic PTLD. Unsupervised nonhierarchical clustering of the viral and cellular microRNAome distinguished non-EBV-associated from EBV-associated samples and identified a separate group of EBV-associated pCNS PTLD that displayed reduced levels of B cell lymphoma associated oncomiRs such as hsa-miR-155, -21, -221 and the hsa-miR-17-92 cluster. EBV has a major impact on viral and cellular microRNA expression in EBV-associated pCNS PTLD.

Complete and Durable Responses in Primary Central Nervous System Posttransplant Lymphoproliferative Disorder with Zidovudine, Ganciclovir, Rituximab, and Dexamethasone

“…Some Hodgkin’s and non-Hodgkin’s B-cell neoplasms are considered “EBV-associated” based on detection of EBV-encoded RNA in tumor tissue by in situ hybridization (EBER-ISH) 3,4 . Over 90% of PCNS-PTLD cases show EBV-association by immunohistochemistry 5 . Patients with acquired, iatrogenic, or congenital immunodeficiency are at increased risk of developing an EBV associated B-cell neoplasm 6 .…”

“…Antiviral therapy targeting lytic gene expression is shown to be an effective treatment in some EBV-associated neoplasms 19 with in vitro data showing the additive induction of apoptosis in EBV+ cell lines treated with AZT and GCV 20,21 . Furthermore, constitutively active lytic-phase gene expression has been demonstrated in EBV+ PCNS-PTLD and systemic PTLDs 5,22,23 , raising the potential for antiviral therapy as an effective therapeutic option. Roychowdhury and colleagues demonstrated the effectiveness of AZT and GCV plus WBRT in preclinical models of EBV+ PCNS-PTLD and report a patient successfully treated with AZT and GCV without radiation 22 .…”

Epstein–Barr Virus: Diseases Linked to Infection and Transformation

“…By detecting the EBV and cellular microRNAome in PTLD (Forte et al, 2012; Harris-Arnold et al, 2015), studies showed that there are two different microRNA profiles identified in primary central nervous system post-transplant lymphoproliferative disorders (pCNS PTLD). First, EBV microRNAs interacts with the cellular microRNAome similarly to that of EBV-associated systemic PTLD and the second could be limited to the immunological functions associated with the central nervous system (Moscato et al, 2013; Fink et al, 2014). Although, a limited expression of latency genes is also seen in EBV associated systemic PTLD, based on promoter utilization it is still considered to be latency III (Fink et al, 2014).…”

“…First, EBV microRNAs interacts with the cellular microRNAome similarly to that of EBV-associated systemic PTLD and the second could be limited to the immunological functions associated with the central nervous system (Moscato et al, 2013; Fink et al, 2014). Although, a limited expression of latency genes is also seen in EBV associated systemic PTLD, based on promoter utilization it is still considered to be latency III (Fink et al, 2014). A higher frequency of EBV in pCNS PTLD compared to systematic PTLD may result in pathological differences (Cavaliere et al, 2010).…”

When to use in situ hybridization for the detection of Epstein-Barr virus: a review of Epstein-Barr virus-associated lymphomas

“…BHRF1 miRNA suppresses expression of CXCL-11, an interferon-inducible chemokine and T cell attractant, which contributes to evasion of EBV-infected tumor cells by immunosurveillance of the host [26]. BART miRNA are expressed in each state of latency, and BART miRNA and BHRF1 are expressed in all EBV-positive PTLD [27], suggesting a significant role of the viral miRNAs of EBV in the etiology of EBV-positive lymphomas.…”