The Polycomb Group Protein Bmi-1 is essential for the growth of Multiple Myeloma cells
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE21912 | GEO | 2010/05/19
SECONDARY ACCESSION(S): PRJNA126835
REPOSITORIES: GEO
Similar Datasets
Project description:The RPMI-8226 human multiple myeloma cell line was stably infected with either a validated shRNA against BMI1 or a control shRNA. RNA was prepared from these lines, +/- doxycycline induction and at various time points post-induction. Samples were hybridized on the Affymetrix U133plus2 human genome expression microarray. The RPMI-8226 human multiple myeloma cell line was stably infected with either a validated shRNA against BMI1 or a control shRNA. RNA was prepared from these lines, +/- doxycycline induction and at various time points post-induction. Samples were hybridized on the Affymetrix U133plus2 human genome expression microarray.
2010-06-09 | E-GEOD-21912 | biostudies-arrayexpress
Project description:BMI1 is a polycomb protein and its overexpression has been correlated with cancer development and aggressiveness. We previously reported that v-myc avian myelocytomatosis viral oncogene neuroblastoma-derived homolog (MYCN)-induced BMI1 positively regulated neuroblastoma (NB) cell proliferation via the transcriptional suppression of tumor suppressors in NB cells. In order to evaluate the potential of BMI1 as a new target for NB therapy, we herein examined the effects of BMI1 reductions on NB cell differentiation and apoptotic NB cell death. BMI1 knockdown (KD) up to 7 days in NB cells significantly induced their differentiation. BMI1 depletion up to 14 days significantly induced apoptotic NB cell death along with the activation of p53, increases in p73, and induction of p53 family downstream molecules. BMI1 depletion in vivo markedly suppressed NB xenograft tumor growth. A pathological analysis using the TUNEL assay indicated the induction of apoptotic cell death. BMI1 reductions activated ATM and increased γ-H2AX in NB cells. Importantly, these DNA damage signals and apoptotic cell death were not canceled by transduction of polycomb group molecules EZH2 and RING1B. Further, EZH2 or RING1B knockdown could not induce apoptotic NB cell death at the same level of BMI1 KD. Together, BMI1 appears to be a promising target of molecular therapy for NB tumors and our report clarified, for the first time, the shared role of PcG proteins in DNA damage response of NB cells.
2022-11-08 | GSE189449 | GEO
Project description:Although new therapies have doubled the survival of multiple myeloma (MM) patients, this remains an incurable disease. It has been postulated that the so-called MM Cancer Stem Cells (MM-CSC) would be responsible for tumor initiation and relapse but their unequivocal identification remains unclear. Here, we investigated in a panel of MM cell lines the presence of CD20+ cells harboring a MM-CSC phenotype. Among the multiple cell lines investigated, only a small population of CD20dim+ cells (0.3%) in the RPMI-8226 cell line was found. CD20dim+ RPMI-8226 cells expressed the plasma cell markers CD38 and CD138 and were CD19-CD27-. Additionally, CD20dim+ RPMI-8226 cells did not exhibit stem-cell markers as shown by gene expression profiling and the aldehyde dehydrogenase (ALDH) assay. Moreover, we demonstrated that CD20dim+ RPMI-8226 cells are not essential for CB17-SCID mice engraftment and show lower self-renewal potential than the CD20- RPMI-8226 cells. These results do not support CD20+ expression for the identification of MM-CSC.
2012-02-27 | GSE33020 | GEO
Project description:Bmi1 is a component of the Polycomb-repressive complexes (PRC) and essential for maintaining the pool of adult stem cells. PRC are key regulators for embryonic development by modifying chromatin architecture and maintaining gene repression. To assess the role of Bmi1 in pluripotent stem cells and upon exit from pluripotency during differentiation, we studied forced Bmi1 expression in mouse embryonic stem cells (ESC). We found that ESC do not express detectable levels of Bmi1 RNA and protein and that forced Bmi1 expression had no obvious influence on ESC self-renewal. However, upon ESC differentiation Bmi1 effectively enhanced development of hematopoietic cells. Global transcriptional profiling identified a large array of genes that were differentially regulated during ESC differentiation by Bmi1. Importantly, we found that Bmi1 induced a prominent up-regulation of Gata2, a zinc finger transcription factor, which is essential for primitive hematopoietic cell generation from mesoderm. In addition, Bmi1 caused sustained growth and a more than 100-fold expansion of ESC-derived hematopoietic stem/progenitor cells within 2-3 weeks of culture. The enhanced proliferative capacity was associated with reduced Ink4a/Arf expression in Bmi1-transduced cells. Taken together, our experiments demonstrate distinct activities of Bmi1 in ESC and ESC-derived hematopoietic progenitor cells. In addition, Bmi1 enhances the propensity of ESC in differentiating towards the hematopoietic lineage. Thus, Bmi1 could be a candidate gene for engineered adult stem cell derivation from ESC. 8 samples in total. Bmi1 embryonic stem cells sample_1 (Bmi1_ESC_1) Bmi1 embryonic stem cells sample_2 (Bmi1_ESC_2) Untreated CCE embryonic stem cells (CCE_ESC_Control) Empty vector CCE embryonic stem cells (CCE_ESC_Vector) Bmi1 embryoid body sample_1 (Bmi1_EB_1) Bmi1 embryoid body sample_2 (Bmi1_EB_2) Empty vector control embryoid body sample_1 (Vector_EB_1) Empty vector control embryoid body sample_2 (Vector_EB_2)
2011-04-29 | E-GEOD-20958 | biostudies-arrayexpress
Project description:This deposition is of TMT-MS datasets for multiple myeloma RPMI 8226 WT cells treated with DMSO or XL44.
| MSV000092929 | MassIVE
Project description:Bmi1 is a component of the Polycomb-repressive complexes (PRC) and essential for maintaining the pool of adult stem cells. PRC are key regulators for embryonic development by modifying chromatin architecture and maintaining gene repression. To assess the role of Bmi1 in pluripotent stem cells and upon exit from pluripotency during differentiation, we studied forced Bmi1 expression in mouse embryonic stem cells (ESC). We found that ESC do not express detectable levels of Bmi1 RNA and protein and that forced Bmi1 expression had no obvious influence on ESC self-renewal. However, upon ESC differentiation Bmi1 effectively enhanced development of hematopoietic cells. Global transcriptional profiling identified a large array of genes that were differentially regulated during ESC differentiation by Bmi1. Importantly, we found that Bmi1 induced a prominent up-regulation of Gata2, a zinc finger transcription factor, which is essential for primitive hematopoietic cell generation from mesoderm. In addition, Bmi1 caused sustained growth and a more than 100-fold expansion of ESC-derived hematopoietic stem/progenitor cells within 2-3 weeks of culture. The enhanced proliferative capacity was associated with reduced Ink4a/Arf expression in Bmi1-transduced cells. Taken together, our experiments demonstrate distinct activities of Bmi1 in ESC and ESC-derived hematopoietic progenitor cells. In addition, Bmi1 enhances the propensity of ESC in differentiating towards the hematopoietic lineage. Thus, Bmi1 could be a candidate gene for engineered adult stem cell derivation from ESC.
2011-04-29 | GSE20958 | GEO
Project description:The Bmi1 Polycomb protein is involved in the epigenetic repressive control of self renewal and survival of cancer initiating cells. In Chronic Myeloid Leukemia (CML), bmi1 expression increases gradually as the disease progresses from a chronic latent phase to a deadly blast crisis. We developped an inducible shRNA system to silence Bmi1 in the human K562 chronic myeloid leukemia (CML) cell line in order to identify new Bmi1-target genes. Gene profiling was performed on inducible shBmi1-K562 cells incubated without (P3-K562+shBMI1) or with doxycycline for 96h (P4-K562+shBMI1+doxycycline) using HG-U133 Plus2 Affymetrix Arrays.
2015-05-12 | E-GEOD-54262 | biostudies-arrayexpress
Project description:Multiple Myeloma (MM) is an hematological malignancy. MM cells are resistant to X-ray irradiations. We irradiated RPMI 8226 cancer cells with C-ions, which are more energetic than X-ray irradiations. We found that MM cells, RPMI 8226, are also resistant to C-ion irradiations. We used microarrays to investigate the mechanisms of MM cell resistance to C-ion irradiations.
2016-01-05 | GSE76471 | GEO
Project description:The fetal (HbF)-to-adult (HbA) hemoglobin switch is a paradigm for developmental gene expression control with relevance to sickle cell disease and beta-thalassemia. Polycomb repressive complex (PRC) proteins regulate this switch, and an inhibitor of the EED subunit of PRC2 entered clinical trials for fetal hemoglobin activation. Yet, how PcG complexes function in this process, their target genes and relevant subunit composition are unknown. Here, we identified the PRC1 subunit BMI1 as a novel HbF repressor. We uncovered LIN28B, IGF2BP1, and IGF2BP3 as direct BMI1 targets and demonstrate that they account for the BMI1 effects. BMI1 functions as part of the canonical PRC1 (cPRC1) subcomplex as revealed by the physical and functional dissection of BMI1 protein partners. Lastly, we demonstrate that BMI1/cPRC1 acts in concert with the PRC2 to repress HbF through the same target genes. Our study illuminates how PRC silences HbF, highlighting an epigenetic mechanism involved in hemoglobin switching.
2023-03-01 | GSE218232 | GEO
Project description:The fetal (HbF)-to-adult (HbA) hemoglobin switch is a paradigm for developmental gene expression control with relevance to sickle cell disease and beta-thalassemia. Polycomb repressive complex (PRC) proteins regulate this switch, and an inhibitor of the EED subunit of PRC2 entered clinical trials for fetal hemoglobin activation. Yet, how PcG complexes function in this process, their target genes and relevant subunit composition are unknown. Here, we identified the PRC1 subunit BMI1 as a novel HbF repressor. We uncovered LIN28B, IGF2BP1, and IGF2BP3 as direct BMI1 targets and demonstrate that they account for the BMI1 effects. BMI1 functions as part of the canonical PRC1 (cPRC1) subcomplex as revealed by the physical and functional dissection of BMI1 protein partners. Lastly, we demonstrate that BMI1/cPRC1 acts in concert with the PRC2 to repress HbF through the same target genes. Our study illuminates how PRC silences HbF, highlighting an epigenetic mechanism involved in hemoglobin switching.
2023-03-01 | GSE218231 | GEO