TY - JOUR
T1 - A yeast-based assay identifies drugs that interfere with immune evasion of the Epstein-Barr virus
AU - Voisset, Cécile
AU - Daskalogianni, Chrysoula
AU - Contesse, Marie Astrid
AU - Mazars, Anne
AU - Arbach, Hratch
AU - Le Cann, Marie
AU - Soubigou, Flavie
AU - Apcher, Sébastien
AU - Fah̊raeus, Robin
AU - Blondel, Marc
PY - 2014/1/1
Y1 - 2014/1/1
N2 - Epstein-Barr virus (EBV) is tightly associated with certain human cancers, but there is as yet no specific treatment against EBV-related diseases. The EBV-encoded EBNA1 protein is essential to maintain viral episomes and for viral persistence. As such, EBNA1 is expressed in all EBV-infected cells, and is highly antigenic. All infected individuals, including individuals with cancer, have CD8+ T cells directed towards EBNA1 epitopes, yet the immune system fails to detect and destroy cells harboring the virus. EBV immune evasion depends on the capacity of the Gly-Ala repeat (GAr) domain of EBNA1 to inhibit the translation of its own mRNA in cis, thereby limiting the production of EBNA1-derived antigenic peptides presented by the major histocompatibility complex (MHC) class I pathway. Here we establish a yeast-based assay for monitoring GAr-dependent inhibition of translation. Using this assay we identify doxorubicin (DXR) as a compound that specifically interferes with the GAr effect on translation in yeast. DXR targets the topoisomerase-II-DNA complexes and thereby causes genomic damage. We show, however, that the genotoxic effect of DXR and various analogs thereof is uncoupled from the effect on GAr-mediated translation control. This is further supported by the observation that etoposide and teniposide, representing another class of topoisomerase-II-DNA targeting drugs, have no effect on GAr-mediated translation control. DXR and active analogs stimulate, in a GAr-dependent manner, EBNA1 expression in mammalian cells and overcome GAr-dependent restriction of MHC class I antigen presentation. These results validate our approach as an effective high-throughput screening assay to identify drugs that interfere with EBV immune evasion and, thus, constitute candidates for treating EBV-related diseases, in particular EBV-associated cancers.
AB - Epstein-Barr virus (EBV) is tightly associated with certain human cancers, but there is as yet no specific treatment against EBV-related diseases. The EBV-encoded EBNA1 protein is essential to maintain viral episomes and for viral persistence. As such, EBNA1 is expressed in all EBV-infected cells, and is highly antigenic. All infected individuals, including individuals with cancer, have CD8+ T cells directed towards EBNA1 epitopes, yet the immune system fails to detect and destroy cells harboring the virus. EBV immune evasion depends on the capacity of the Gly-Ala repeat (GAr) domain of EBNA1 to inhibit the translation of its own mRNA in cis, thereby limiting the production of EBNA1-derived antigenic peptides presented by the major histocompatibility complex (MHC) class I pathway. Here we establish a yeast-based assay for monitoring GAr-dependent inhibition of translation. Using this assay we identify doxorubicin (DXR) as a compound that specifically interferes with the GAr effect on translation in yeast. DXR targets the topoisomerase-II-DNA complexes and thereby causes genomic damage. We show, however, that the genotoxic effect of DXR and various analogs thereof is uncoupled from the effect on GAr-mediated translation control. This is further supported by the observation that etoposide and teniposide, representing another class of topoisomerase-II-DNA targeting drugs, have no effect on GAr-mediated translation control. DXR and active analogs stimulate, in a GAr-dependent manner, EBNA1 expression in mammalian cells and overcome GAr-dependent restriction of MHC class I antigen presentation. These results validate our approach as an effective high-throughput screening assay to identify drugs that interfere with EBV immune evasion and, thus, constitute candidates for treating EBV-related diseases, in particular EBV-associated cancers.
KW - 5-fluorouracil
KW - Cell-based drug screening
KW - Daunorubicin
KW - Doxorubicin
KW - EBNA1 GAr domain
KW - EBV-associated cancers
KW - Immune evasion
KW - Yeast-based models
UR - http://www.scopus.com/inward/record.url?scp=84897945239&partnerID=8YFLogxK
U2 - 10.1242/dmm.014308
DO - 10.1242/dmm.014308
M3 - Article
C2 - 24558096
AN - SCOPUS:84897945239
SN - 1754-8403
VL - 7
SP - 435
EP - 444
JO - DMM Disease Models and Mechanisms
JF - DMM Disease Models and Mechanisms
IS - 4
ER -