Project description:XMRV, or xenotropic murine leukemia virus (MLV)-related virus, is a novel gammaretrovirus originally identified in studies that analyzed tissue from prostate cancer patients in 2006 and blood from patients with chronic fatigue syndrome (CFS) in 2009. However, a large number of subsequent studies failed to confirm a link between XMRV infection and CFS or prostate cancer. On the contrary, recent evidence indicates that XMRV is a contaminant originating from the recombination of two mouse endogenous retroviruses during passaging of a prostate tumor xenograft (CWR22) in mice, generating laboratory-derived cell lines that are XMRV-infected. To confirm or refute an association between XMRV and prostate cancer, we analyzed prostate cancer tissues and plasma from a prospectively collected cohort of 39 patients as well as archival RNA and prostate tissue from the original 2006 study. Despite comprehensive microarray, PCR, FISH, and serological testing, XMRV was not detected in any of the newly collected samples or in archival tissue, although archival RNA remained XMRV-positive. Notably, archival VP62 prostate tissue, from which the prototype XMRV strain is derived, tested negative for XMRV on re-analysis. Analysis of viral genomic and human mitochondrial sequences revealed that all previously characterized XMRV strains are identical and that the archival RNA had been contaminated by an XMRV-infected laboratory cell line. These findings reveal no association between XMRV and prostate cancer, and underscore the conclusion that XMRV is not a naturally acquired human infection.
Project description:XMRV, or xenotropic murine leukemia virus (MLV)-related virus, is a novel gammaretrovirus originally identified in studies that analyzed tissue from prostate cancer patients in 2006 and blood from patients with chronic fatigue syndrome (CFS) in 2009. However, a large number of subsequent studies failed to confirm a link between XMRV infection and CFS or prostate cancer. On the contrary, recent evidence indicates that XMRV is a contaminant originating from the recombination of two mouse endogenous retroviruses during passaging of a prostate tumor xenograft (CWR22) in mice, generating laboratory-derived cell lines that are XMRV-infected. To confirm or refute an association between XMRV and prostate cancer, we analyzed prostate cancer tissues and plasma from a prospectively collected cohort of 39 patients as well as archival RNA and prostate tissue from the original 2006 study. Despite comprehensive microarray, PCR, FISH, and serological testing, XMRV was not detected in any of the newly collected samples or in archival tissue, although archival RNA remained XMRV-positive. Notably, archival VP62 prostate tissue, from which the prototype XMRV strain is derived, tested negative for XMRV on re-analysis. Analysis of viral genomic and human mitochondrial sequences revealed that all previously characterized XMRV strains are identical and that the archival RNA had been contaminated by an XMRV-infected laboratory cell line. These findings reveal no association between XMRV and prostate cancer, and underscore the conclusion that XMRV is not a naturally acquired human infection. The Virochip microarray (version 5.0, Viro5AGL-60K platform) was used to screen RNA extracts from prostate tissue for XMRV to determine whether there is an association between the virus and prostate cancer. We used the ViroChip microarray to screen 22 archived prostate biopsies extracted in 2006 and 39 prospectively collected prostate biopsies for the virus, Xenotropic Murine Leukemia Virus-Related Virus (XMRV). We used custom-commercial microarrays from Agilent Technologies. The microarray platform GPL11662 consists of 62,976 probes [PMID 21779173], including all of the viral probes from the previous v2.0 (MV), v3.0 (V3) and v4.0 (V4) designs [PMIDs 18768820, 16983602, 16609730, 12429852, 9843981]. For this study, 61 experimental ViroChip microarrays derived from prospectively collected RNA extracted prostate tissue and frozen RNA from archived prostate from a 2006 study were analyzed. Additionally, two XMRV-positive control microarrays from the cell line, 22Rv1, were hybridized, for a total of 63 ViroChip microarrays. Some RNA extracts were enriched for polyadenylated (polyA) transcripts prior to hybridization.
Project description:XMRV is a gammaretrovirus that was thought to be associated with prostate cancer (PC) and chronic fatigue syndrome (CFS) in humans until recently. The virus is culturable in various cells of human origin like lymphocytes, NK cells, neuronal cells, and prostate cell lines. MicroRNAs (miRNAs), which regulate gene expression, were so far not identified in cells infected with XMRV in culture. Two prostate cancer cell lines (LNCaP and DU145) and two primary cells (peripheral blood lymphocytes (PBLs) and monocyte-derived macrophages (MDMs)) were infected with XMRV. Total mRNA was extracted from mock- and virus-infected cells at 6, 24 and 48 hours post-infection and evaluated for microRNA profile in a microarray. MicroRNA expression profiles of XMRV-infected continuous prostate cancer cell lines differ from that of virus-infected primary cells (PBLs and MDMs). miR-193a-3p and miRPlus-E1245 were observed to be specific to XMRV infection in all 4 cell types. While miR-193a-3p levels were down-regulated, miRPlus-E1245 on the other hand exhibited varied expression among the 4 cell types. The present study demonstrates that cellular microRNAs are expressed during XMRV infection of human cells. This is the first report demonstrating the regulation of miR193a-3p and miRPlus-E1245 during XMRV infection in four different human cell types.
Project description:XMRV is a gammaretrovirus that was thought to be associated with prostate cancer (PC) and chronic fatigue syndrome (CFS) in humans until recently. The virus is culturable in various cells of human origin like lymphocytes, NK cells, neuronal cells, and prostate cell lines. MicroRNAs (miRNAs), which regulate gene expression, were so far not identified in cells infected with XMRV in culture. Two prostate cancer cell lines (LNCaP and DU145) and two primary cells (peripheral blood lymphocytes (PBLs) and monocyte-derived macrophages (MDMs)) were infected with XMRV. Total mRNA was extracted from mock- and virus-infected cells at 6, 24 and 48 hours post-infection and evaluated for microRNA profile in a microarray. MicroRNA expression profiles of XMRV-infected continuous prostate cancer cell lines differ from that of virus-infected primary cells (PBLs and MDMs). miR-193a-3p and miRPlus-E1245 were observed to be specific to XMRV infection in all 4 cell types. While miR-193a-3p levels were down-regulated, miRPlus-E1245 on the other hand exhibited varied expression among the 4 cell types. The present study demonstrates that cellular microRNAs are expressed during XMRV infection of human cells. This is the first report demonstrating the regulation of miR193a-3p and miRPlus-E1245 during XMRV infection in four different human cell types.
Project description:MicroRNAs (miRNAs) are small non-coding RNAs that can exert multilevel inhibition/repression at a post-transcriptional or protein synthesis level during disease or development. Characterisation of miRNAs in adult mammalian brains by deep sequencing has been reported previously. However, to date, no small RNA profiling of the developing brain has been undertaken using this method. We have performed deep sequencing and small RNA analysis of a developing (E15.5) mouse brain. We identified the expression of 294 known miRNAs in the E15.5 developing mouse brain, which were mostly represented by let-7 family and other brain-specific miRNAs such as miR-9 and miR-124. We also discovered 4 putative 22-23nt miRNAs: mm_br_e15_1181, mm_br_e15_279920, mm_br_e15_96719 and mm_br_e15_294354 each with a 70-76nt predicted pre-miRNA. We validated the 4 putative miRNAs and further characterised one of them, mm_br_e15_1181, throughout embryogenesis. Mm_br_e15_1181 biogenesis was Dicer1-dependent and was expressed in E3.5 blastocysts and E7 whole embryos. Embryo-wide expression patterns were observed at E9.5 and E11.5 followed by a near complete loss of expression by E13.5, with expression restricted to a specialised layer of cells within the developing and early postnatal brain. Mm_br_e15_1181 was upregulated during neurodifferentiation of P19 teratocarcinoma cells. This novel miRNA has been identified as miR-3099. We have generated and analysed the first deep sequencing dataset of small RNA sequences of the developing mouse brain. The analysis revealed a novel miRNA, miR-3099, with potential regulatory effects on early embryogenesis, and involvement in neuronal cell differentiation/function in the brain during late embryonic and early neonatal development.
Project description:MicroRNAs (miRNAs) are small non-coding RNAs that can exert multilevel inhibition/repression at a post-transcriptional or protein synthesis level during disease or development. Characterisation of miRNAs in adult mammalian brains by deep sequencing has been reported previously. However, to date, no small RNA profiling of the developing brain has been undertaken using this method. We have performed deep sequencing and small RNA analysis of a developing (E15.5) mouse brain. We identified the expression of 294 known miRNAs in the E15.5 developing mouse brain, which were mostly represented by let-7 family and other brain-specific miRNAs such as miR-9 and miR-124. We also discovered 4 putative 22-23nt miRNAs: mm_br_e15_1181, mm_br_e15_279920, mm_br_e15_96719 and mm_br_e15_294354 each with a 70-76nt predicted pre-miRNA. We validated the 4 putative miRNAs and further characterised one of them, mm_br_e15_1181, throughout embryogenesis. Mm_br_e15_1181 biogenesis was Dicer1-dependent and was expressed in E3.5 blastocysts and E7 whole embryos. Embryo-wide expression patterns were observed at E9.5 and E11.5 followed by a near complete loss of expression by E13.5, with expression restricted to a specialised layer of cells within the developing and early postnatal brain. Mm_br_e15_1181 was upregulated during neurodifferentiation of P19 teratocarcinoma cells. This novel miRNA has been identified as miR-3099. We have generated and analysed the first deep sequencing dataset of small RNA sequences of the developing mouse brain. The analysis revealed a novel miRNA, miR-3099, with potential regulatory effects on early embryogenesis, and involvement in neuronal cell differentiation/function in the brain during late embryonic and early neonatal development. Deep sequencing analysis of small RNAs isolated from an E15.5 mouse brain.
Project description:XMRV is a gammaretrovirus that was thought to be associated with prostate cancer (PC) and chronic fatigue syndrome (CFS) in humans until recently. The virus is culturable in various cells of human origin like lymphocytes, NK cells, neuronal cells, and prostate cell lines. MicroRNAs (miRNAs), which regulate gene expression, were so far not identified in cells infected with XMRV in culture. Two prostate cancer cell lines (LNCaP and DU145) and two primary cells (peripheral blood lymphocytes (PBLs) and monocyte-derived macrophages (MDMs)) were infected with XMRV. Total mRNA was extracted from mock- and virus-infected cells at 6, 24 and 48 hours post-infection and evaluated for microRNA profile in a microarray. MicroRNA expression profiles of XMRV-infected continuous prostate cancer cell lines differ from that of virus-infected primary cells (PBLs and MDMs). miR-193a-3p and miRPlus-E1245 were observed to be specific to XMRV infection in all 4 cell types. While miR-193a-3p levels were down-regulated, miRPlus-E1245 on the other hand exhibited varied expression among the 4 cell types. The present study demonstrates that cellular microRNAs are expressed during XMRV infection of human cells. This is the first report demonstrating the regulation of miR193a-3p and miRPlus-E1245 during XMRV infection in four different human cell types. Two prostate cancer cell lines (LNCaP and DU145) and two primary cells (peripheral blood lymphocytes (PBLs) and monocyte-derived macrophages (MDMs)) were infected with XMRV. Total mRNA was extracted from mock- and virus-infected cells at 6, 24 and 48 hours post-infection in duplicates and evaluated for microRNA profile in a microarray. Each test sample RNA was labeled with Hy3 and the reference pool (made by pooling all 24 test samples in each run) was labeled with Hy5.
Project description:XMRV is a gammaretrovirus that was thought to be associated with prostate cancer (PC) and chronic fatigue syndrome (CFS) in humans until recently. The virus is culturable in various cells of human origin like lymphocytes, NK cells, neuronal cells, and prostate cell lines. MicroRNAs (miRNAs), which regulate gene expression, were so far not identified in cells infected with XMRV in culture. Two prostate cancer cell lines (LNCaP and DU145) and two primary cells (peripheral blood lymphocytes (PBLs) and monocyte-derived macrophages (MDMs)) were infected with XMRV. Total mRNA was extracted from mock- and virus-infected cells at 6, 24 and 48 hours post-infection and evaluated for microRNA profile in a microarray. MicroRNA expression profiles of XMRV-infected continuous prostate cancer cell lines differ from that of virus-infected primary cells (PBLs and MDMs). miR-193a-3p and miRPlus-E1245 were observed to be specific to XMRV infection in all 4 cell types. While miR-193a-3p levels were down-regulated, miRPlus-E1245 on the other hand exhibited varied expression among the 4 cell types. The present study demonstrates that cellular microRNAs are expressed during XMRV infection of human cells. This is the first report demonstrating the regulation of miR193a-3p and miRPlus-E1245 during XMRV infection in four different human cell types. Two prostate cancer cell lines (LNCaP and DU145) and two primary cells (peripheral blood lymphocytes (PBLs) and monocyte-derived macrophages (MDMs)) were infected with XMRV. Total mRNA was extracted from mock- and virus-infected cells at 6, 24 and 48 hours post-infection in duplicates and evaluated for microRNA profile in a microarray. Each test sample RNA was labeled with Hy3 and the reference pool (made by pooling all 24 test samples in each run) was labeled with Hy5.
Project description:We have previously proposed two distinct molecular mechanisms by which SCL binds its targets in hematopoiesis; either by direct contact with specific DNA sequences or by indirect recruitment through interaction with other proteins. We have established that direct DNA binding is the major non-redundant mechanism SCL exerts in red cells. A DNA-binding mutant form of SCL (SCLRER) had detrimental effect on erythropoiesis in vivo. To extend these data to a molecular and mechanistic level, we have set out to identify the genomic sequences bound by SCL in vivo in erythroid precursors; we performed anti-SCL ChIP assays on immature, Ter119- erythroid cell populations isolated from day E12.5 wild-type (SCLWT/WT) fetal livers followed by ultra-throughput sequencing (ChIP-SEQ). To compare SCL’s direct versus indirect DNA-binding activities and, thus, gain insight into its mechanisms of action, we also analysed material isolated from SCLRER/RER fetal livers. anti-SCL ChIP-enriched DNA from mouse fetal liver erythroblast chromatin was analysed by Solexa sequencing. Four samples were processed: chromatin from SCL wildtype erythroblasts (WT-SCL) and SCL mutant erythroblasts (RER-SCL) were ChIPed by anti-SCL antibody and sequenced with their respective 'no antibody' controls.
Project description:This SuperSeries is composed of the following subset Series: GSE37786: Identification of XMRV Infection-Associated microRNAs in Four Cell Types in Culture (Experiment A) GSE37787: Identification of XMRV Infection-Associated microRNAs in Four Cell Types in Culture (Experiment B) Refer to individual Series