Project description:To identify differentially expressed human and viral miRNAs across a panel of B-cell lines, including several primary effusion lymphomas (PEL). Gammaherpesvirus and host cell microRNAs (miRNAs) together modulate gene expression in normal and malignant cells. Using microRNA microarrays, we determined the expression of mature viral and host cellular miRNAs in a series of B cell tumours that include Kaposiâs Sarcoma-associated herpesvirus (KSHV) infected Primary Effusion Lymphoma (PEL) and Epstein-Barr virus (EBV) infected Burkittâs lymphoma (BL) cell lines. We show that 35 host miRNAs were constitutively expressed in all the B cell lymphomas and differences in viral miRNA expression were evident between herpesvirus positive tumour types. Furthermore, we show that in PEL, miR-221 and miR-222 expression is defective due to a lack of transcript expression rather than mutation in the miRNA encoding loci. Absence of miR-221 and miR-222 resulted in the enhanced expression of the known target gene p27 (CDKN1B) and reintroduction of miR221 in PEL reduces p27 protein expression. miRNA expression profiling of a panel of 25 B-cell line samples.
Project description:To identify differentially expressed human and viral miRNAs across a panel of B-cell lines, including several primary effusion lymphomas (PEL). Gammaherpesvirus and host cell microRNAs (miRNAs) together modulate gene expression in normal and malignant cells. Using microRNA microarrays, we determined the expression of mature viral and host cellular miRNAs in a series of B cell tumours that include Kaposi’s Sarcoma-associated herpesvirus (KSHV) infected Primary Effusion Lymphoma (PEL) and Epstein-Barr virus (EBV) infected Burkitt’s lymphoma (BL) cell lines. We show that 35 host miRNAs were constitutively expressed in all the B cell lymphomas and differences in viral miRNA expression were evident between herpesvirus positive tumour types. Furthermore, we show that in PEL, miR-221 and miR-222 expression is defective due to a lack of transcript expression rather than mutation in the miRNA encoding loci. Absence of miR-221 and miR-222 resulted in the enhanced expression of the known target gene p27 (CDKN1B) and reintroduction of miR221 in PEL reduces p27 protein expression.
Project description:1) To identify changes in gene expression upon over-expression of hsa-miR-221 in JSC1 cells. 2) To identify human miRNA targets expressed in a panel of B-cell lines. Gammaherpesvirus and host cell microRNAs (miRNAs) together modulate gene expression in normal and malignant cells. Using microRNA microarrays, we determined the expression of mature viral and host cellular miRNAs in a series of B cell tumours that include Kaposiâs Sarcoma-associated herpesvirus (KSHV) infected Primary Effusion Lymphoma (PEL) and Epstein-Barr virus (EBV) infected Burkittâs lymphoma (BL) cell lines. We show that 35 host miRNAs were constitutively expressed in all the B cell lymphomas and differences in viral miRNA expression were evident between herpesvirus positive tumour types. Furthermore, we show that in PEL, miR-221 and miR-222 expression is defective due to a lack of transcript expression rather than mutation in the miRNA encoding loci. Absence of miR-221 and miR-222 resulted in the enhanced expression of the known target gene p27 (CDKN1B) and reintroduction of miR221 in PEL reduces p27 protein expression. The dataset comes in two parts. 1) 6 JSC1 samples: 2 with miR-221 lentiviral vector, 2 without and 2 with K5 short hairpin RNA as control. 2) A panel of 14 B-cell line samples. Each of the 20 samples was Cy5 labelled and run with Cy3-labelled Stratagene reference RNA.
Project description:1) To identify changes in gene expression upon over-expression of hsa-miR-221 in JSC1 cells. 2) To identify human miRNA targets expressed in a panel of B-cell lines. Gammaherpesvirus and host cell microRNAs (miRNAs) together modulate gene expression in normal and malignant cells. Using microRNA microarrays, we determined the expression of mature viral and host cellular miRNAs in a series of B cell tumours that include Kaposi’s Sarcoma-associated herpesvirus (KSHV) infected Primary Effusion Lymphoma (PEL) and Epstein-Barr virus (EBV) infected Burkitt’s lymphoma (BL) cell lines. We show that 35 host miRNAs were constitutively expressed in all the B cell lymphomas and differences in viral miRNA expression were evident between herpesvirus positive tumour types. Furthermore, we show that in PEL, miR-221 and miR-222 expression is defective due to a lack of transcript expression rather than mutation in the miRNA encoding loci. Absence of miR-221 and miR-222 resulted in the enhanced expression of the known target gene p27 (CDKN1B) and reintroduction of miR221 in PEL reduces p27 protein expression.
Project description:Primary effusion lymphoma (PEL) is caused by Kaposi's sarcoma-associated herpesvirus (KSHV) and frequently also harbors Epstein-Barr virus (EBV). The expression of KSHV- and, often, EBV-encoded microRNAs (miRNAs) in PELs suggests a role for these miRNAs in viral latency and lymphomagenesis. Here we report the direct and transcriptome-wide identification of miRNA target sites for all miRNAs expressed in PEL cell lines. The resulting dataset revealed that KSHV miRNAs directly target more than 2000 cellular mRNAs encoding proteins that function in pathways with relevance to KSHV pathogenesis. Moreover, ~50% of these mRNAs are also targeted by EBV miRNAs, via distinct binding sites. In addition to a known viral analog of miR-155, we show that KSHV encodes a viral miRNA that mimics cellular miR-142-3p function. In summary, these experiments identify an extensive list of mRNAs targeted by KSHV miRNAs and indicate that these are likely to strongly influence viral replication and pathogenesis. small RNA sequencing, 3 samples Ago2 (EIF2C2) PAR-CLIP, 2 samples
Project description:Non-Hodgkin lymphomas (NHL) make up the majority of lymphoma diagnoses and represent a very diverse set of malignancies. We sought to identify kinases uniquely upregulated in different NHL subtypes. Using Multiplexed Inhibitor Bead-mass spectrometry (MIB/MS), we found Tyro3 was uniquely upregulated and important for cell survival in primary effusion lymphoma (PEL), which is a viral lymphoma infected with Kaposi’s sarcoma-associated herpesvirus (KSHV).
Project description:Primary effusion lymphomas (PELs) are specifically associated with KSHV/HHV-8 infection, and most frequently occur in HIV-positive individuals as lymphomatous effusions in the serous cavities without a detectable solid tumor mass. Most PELs have concomitant EBV infection, suggesting that EBV is an important pathogenetic co-factor, although other as yet unidentified cofactors, such as cellular genetic alterations, are also likely to play a role. Lymphomatous effusions that lack KSHV also occur; these are frequently EBV-associated in the setting of HIV infection. Here we used gene expression profile analysis to determine the viral impact on cellular gene expression and the pathogenesis of these lymphomatous effusions. We used the Affymetrix HG-U133A microarray to analyze the gene expression profile of these effusion lymphomas (three virologic groups: KSHV-positive EBV-positive PELs, KSHV-positive EBV-negative PELs and KSHV-negative EBV-positive lymphomatous effusions). Nine cell lines derived from patients with lymphomatous effusions (three from each virologic group and each cell line was done in duplicates.) and three PEL patient samples were used in the study. Our results suggest that KSHV-positive PELs are very different from KSHV-negative lymphomatous effusions, and the genes that are differentially expressed include apoptosis regulators, cell cycle regulators, transcriptional factors and signal transduction regulators. KSHV clearly plays a dominant role in the phenotype of PEL. Within the KSHV-positive PELs, two subgroups can be identified, which were correlated with their EBV viral status. Among these genes (45 gene probes), four were regulators of the MAP kinase pathway that were up-regulated in the KSHV-positive, EBV-negative PELs, suggesting that in the absence of EBV, events that lead to the activation of the MAP kinase pathway may act as a cofactor for the development of PEL. Next we determined whether we could predict the viral status of the three primary patient cases of PEL based on the 45 gene probes that were differentially expressed in KSHV-positive cell lines according to EBV status (pt. 1: KSHV-positive, EBV-positive; Pt. 2: KSHV-positive, low proportion of EBV-positive; pt. 3: KSHV-positive EBV-negative), and we could.<br><br>Samples:<br>KSHV-positive EBV-positive cell lines: BC-1, BC-2, BC-5 <br>KSHV-positive EBV-negative cell lines: BC-3, BCBL-1, PEL-5 <br>KSHV-negative EBV-positive cell lines: IBL4, SM1, BCKN-1 <br>Patient 1: KSHV-positive, EBV-positive <br>Patient 2: KSHV-positive, EBV-positive (low number of positive cells) <br>Patient 3: KSHV-positive, EBV-negative.
Project description:Kaposi’s sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are related human tumor viruses that cause primary effusion lymphomas (PEL) and Burkitt’s lymphomas (BL), respectively. Viral genes expressed in naturally-infected cancer cells contribute to disease pathogenesis; knowing which viral genes are expressed is critical in understanding how these viruses cause cancer. To evaluate the expression of viral genes, we used high-resolution separation and mass spectrometry coupled with custom tiling arrays to align the viral proteomes and transcriptomes of three PEL and two BL cell lines under latent and lytic culture conditions. The majority of viral genes were efficiently detected at the transcript and/or protein level on manipulating the viral life cycle. Overall the correlation of expressed viral proteins and transcripts was highly complementary in both validating and providing orthogonal data with latent/lytic viral gene expression. Our approach also identified novel viral genes in both KSHV and EBV, and extends viral genome annotation. The expression of several previously uncharacterized latent genes were validated at both transcript and protein levels. This systems biology approach coupling proteome and transcriptome measurements provides a comprehensive view of viral gene expression that could not have been attained using each methodology independently. Detection of viral proteins in combination with viral transcripts is a potentially powerful method for establishing virus-disease relationships.
Project description:Primary effusion lymphoma (PEL) is caused by Kaposi's sarcoma-associated herpesvirus (KSHV) and frequently also harbors Epstein-Barr virus (EBV). The expression of KSHV- and, often, EBV-encoded microRNAs (miRNAs) in PELs suggests a role for these miRNAs in viral latency and lymphomagenesis. Here we report the direct and transcriptome-wide identification of miRNA target sites for all miRNAs expressed in PEL cell lines. The resulting dataset revealed that KSHV miRNAs directly target more than 2000 cellular mRNAs encoding proteins that function in pathways with relevance to KSHV pathogenesis. Moreover, ~50% of these mRNAs are also targeted by EBV miRNAs, via distinct binding sites. In addition to a known viral analog of miR-155, we show that KSHV encodes a viral miRNA that mimics cellular miR-142-3p function. In summary, these experiments identify an extensive list of mRNAs targeted by KSHV miRNAs and indicate that these are likely to strongly influence viral replication and pathogenesis.
Project description:EBV-positive cell lines were assayed for expression of EBV miRNAs. The names of the miRNAs are from miRBase from Fall 2007. Microarray probes are tandem complements of the mature miRNA sequence. We assayed Burkitt's lymphoma (BL), Nasopharyngeal carcinoma, post-transplant lymphoproliferative disease (PTLD), primary effusion lymphoma, and lymphoblastoid cell lines. We also assayed primary B cells that were infected with the B95-8 strain of EBV, which was found to express EBV miRNAs as early as 20 hours post infection. We have found PTLD and BLs from HIV-positive donors both express EBV miRNAs. These types of cell lines have not previously been found to express viral miRNAs. We have found that cells that support type I and type II latency express only the BART miRNAs, whereas cells that support type III latency express BART and BHRF1 miRNAs. Furthermore, BL cell lines that spontaneously lose EBV express levels of the viral miRNAs that are at least 5-fold lower than cell lines that do not lose EBV.