Project description:Analyses of gene expression profiling in sinonasal sarcoma (SNS) harboring PAX3-MAML3 fusion gene or PAX3 rearrangement and other types of tumors without having such fusion or rearrangement. The results provide important information for further investigations of the PAX3-MAML3 fusion functions in SNS.
Project description:Analyses of gene expression profiling in sinonasal sarcoma (SNS) harboring PAX3-MAML3 fusion gene or PAX3 rearrangement and other types of tumors without having such fusion or rearrangement. The results provide important information for further investigations of the PAX3-MAML3 fusion functions in SNS. Total RNA was obtained from FFPE tissues of 41 tumors including 8 SNS (6 with PAX3-MAML3 fusion and 2 with PAX3 rearrangement only) and 33 cases from other 10 different types of tumors. Gene expression profiling of fusion group including 8 SNA vs.non-fusion group including 33 control tumors were analyszed.
Project description:Chimeric transcription factors drive lineage-specific oncogenesis but are notoriously difficult to target. Alveolar rhabdomyosarcoma (RMS) is an aggressive childhood soft tissue sarcoma transformed by the pathognomonic PAX3–FOXO1 fusion protein, which governs a core regulatory circuitry transcription factor (CRC TF) network. Here we show that the histone lysine demethylase KDM4B is a therapeutic vulnerability for PAX3–FOXO1+ RMS. Genetic and pharmacologic inhibition of KDM4B significantly delays tumor growth by disrupting the expression of CRC TFs caused by epigenetic alterations of PAX3–FOXO1-governed super enhancers. Combining KDM4B inhibition with cytotoxic chemotherapy leads to significant tumor regression in preclinical PAX3–FOXO1+ RMS models. In summary, we have identified a targetable mechanism required for maintenance of PAX3-FOXO1-related CRC TF network, which may translate to a novel therapeutic approach for fusion-positive RMS.
Project description:Chimeric transcription factors drive lineage-specific oncogenesis but are notoriously difficult to target. Alveolar rhabdomyosarcoma (RMS) is an aggressive childhood soft tissue sarcoma transformed by the pathognomonic PAX3–FOXO1 fusion protein, which governs a core regulatory circuitry transcription factor (CRC TF) network. Here we show that the histone lysine demethylase KDM4B is a therapeutic vulnerability for PAX3–FOXO1+ RMS. Genetic and pharmacologic inhibition of KDM4B significantly delays tumor growth by disrupting the expression of CRC TFs caused by epigenetic alterations of PAX3–FOXO1-governed super enhancers. Combining KDM4B inhibition with cytotoxic chemotherapy leads to significant tumor regression in preclinical PAX3–FOXO1+ RMS models. In summary, we have identified a targetable mechanism required for maintenance of PAX3-FOXO1-related CRC TF network, which may translate to a novel therapeutic approach for fusion-positive RMS.
Project description:Chimeric transcription factors drive lineage-specific oncogenesis but are notoriously difficult to target. Alveolar rhabdomyosarcoma (RMS) is an aggressive childhood soft tissue sarcoma transformed by the pathognomonic PAX3–FOXO1 fusion protein, which governs a core regulatory circuitry transcription factor (CRC TF) network. Here we show that the histone lysine demethylase KDM4B is a therapeutic vulnerability for PAX3–FOXO1+ RMS. Genetic and pharmacologic inhibition of KDM4B significantly delays tumor growth by disrupting the expression of CRC TFs caused by epigenetic alterations of PAX3–FOXO1-governed super enhancers. Combining KDM4B inhibition with cytotoxic chemotherapy leads to significant tumor regression in preclinical PAX3–FOXO1+ RMS models. In summary, we have identified a targetable mechanism required for maintenance of PAX3-FOXO1-related CRC TF network, which may translate to a novel therapeutic approach for fusion-positive RMS.
Project description:Chimeric transcription factors drive lineage-specific oncogenesis but are notoriously difficult to target. Alveolar rhabdomyosarcoma (RMS) is an aggressive childhood soft tissue sarcoma transformed by the pathognomonic PAX3–FOXO1 fusion protein, which governs a core regulatory circuitry transcription factor (CRC TF) network. Here we show that the histone lysine demethylase KDM4B is a therapeutic vulnerability for PAX3–FOXO1+ RMS. Genetic and pharmacologic inhibition of KDM4B significantly delays tumor growth by disrupting the expression of CRC TFs caused by epigenetic alterations of PAX3–FOXO1-governed super enhancers. Combining KDM4B inhibition with cytotoxic chemotherapy leads to significant tumor regression in preclinical PAX3–FOXO1+ RMS models. In summary, we have identified a targetable mechanism required for maintenance of PAX3-FOXO1-related CRC TF network, which may translate to a novel therapeutic approach for fusion-positive RMS.
Project description:Chimeric transcription factors drive lineage-specific oncogenesis but are notoriously difficult to target. Alveolar rhabdomyosarcoma (RMS) is an aggressive childhood soft tissue sarcoma transformed by the pathognomonic PAX3–FOXO1 fusion protein, which governs a core regulatory circuitry transcription factor (CRC TF) network. Here we show that the histone lysine demethylase KDM4B is a therapeutic vulnerability for PAX3–FOXO1+ RMS. Genetic and pharmacologic inhibition of KDM4B significantly delays tumor growth by disrupting the expression of CRC TFs caused by epigenetic alterations of PAX3–FOXO1-governed super enhancers. Combining KDM4B inhibition with cytotoxic chemotherapy leads to significant tumor regression in preclinical PAX3–FOXO1+ RMS models. In summary, we have identified a targetable mechanism required for maintenance of PAX3-FOXO1-related CRC TF network, which may translate to a novel therapeutic approach for fusion-positive RMS.
Project description:Alveolar rhabdomyosarcoma (aRMS) is an aggressive sarcoma of skeletal muscle characterized by expression of the PAX3-FOXO1 fusion gene. Despite its discovery over almost 20 years ago, PAX3-FOXO1 remains an enigmatic tumor driver. Previously, we reported that PAX3-FOXO1 supports aRMS initiation by enabling bypass of cellular senescence. Here, we show that bypass occurs in part by PAX3-FOXO1-mediated upregulation of RASSF4, a Ras-association domain family (RASSF) member, which then suppresses the evolutionarily conserved mammalian Hippo/Mst1 pathway. RASSF4 loss-of-function activates Hippo/Mst1 and inhibits downstream YAP, causing aRMS cell cycle arrest and senescence. This is the first evidence for an oncogenic role for RASSF4, and a novel mechanism for Hippo signaling suppression in human cancer. Human skeletal muscle myoblasts (HSMMs) were retrovirally transduced with either an empty vector (Vp, pK1) or PAX3-FOXO1 (PFp, pK1-PAX3-FOXO1) and selected on puromycin. Presenescent (presen) cells were harvested before the senescence checkpoint. Since cells expressing PAX3-FOXO1 can bypass the senescence checkpoint, postsenescent (postsen) cells expressing PAX3-FOXO1 were also harvested. the gene expression affected by the introduction of PAX3-FOXO1
Project description:We report the genome-wide maps of PAX3-FKHR binding sites. Chromatin immunoprecipitation was performed against PAX3-FKHR positive (Rh4) and PAX3-FKHR negative (RD) rhabdomyosarcoma cells with a monoclonal antibody (pFM2) specific for the fusion region of PAX3-FKHR. We obtained 4 million sequence tags for both input and ChIP DNA that aligned to the human genome. We identified 1,463 binding sites from ChIP-seq of Rh4 cells, none of which appeared from ChIP-seq of fusion negative RD cells. The PAX3-FKHR binding sites were found to associate with 1,072 genes in RMS cells. The data shows that PAX3-FKHR binds to the same sites as PAX3, at the enhancers for MYF5, FGFR4, and the MYOD core enhancer previously shown to be regulated by PAX3. Moreover, our dataset has the precision for rapid identification and validation of novel and specific sequences required for the enhancer activity of MYOD and FGFR4. The genome wide analysis reveals that the PAX3-FKHR sites are: 1) mostly distal to transcription start sites; 2) conserved; 3) enriched for PAX3 motifs; and 4) strongly associated with genes over-expressed in PAX3-FKHR positive RMS cells and tumors. There is little evidence in our dataset for PAX3-FKHR binding at the promoters. In one instance, we show two intronic enhancer elements for MET, rather than at the previously described promoter. The genome-wide analysis further illustrates a strong association between PAX3 and E-box motifs in these binding sites, suggestive of a common co-regulation for many target genes. The map of PAX3-FKHR binding sites provides new links for PAX3 and PAX3-FKHR functions and new targets for RMS therapy. Examination of PAX3-FKHR binding sites in translocation-positive rhabdomyosarcoma cells via ChIP-seq with an antibody specific for the fusion protein.
Project description:Fusion-positive alveolar rhabdomyosarcoma (FP-RMS) is an aggressive pediatric sarcoma driven primarily by the PAX3-FOXO1 fusion oncogene, for which therapies targeting PAX3-FOXO1 are lacking. We screened 62,643 compounds using an engineered cell line that monitors PAX3-FOXO1 transcriptional activity identifying a hitherto uncharacterized compound, PFI-63. RNA-seq, ATAC-seq, and docking analyses implicated histone lysine demethylases (KDMs) as its targets. Enzymatic assays confirmed the inhibition of multiple KDMs with highest selectivity for KDM3B. Structural similarity search of PFI-63 identified PFI-90 with improved solubility and potency. Biophysical binding of PFI-90 to KDM3B was demonstrated using NMR and SPR. PFI-90 suppressed the growth of FP-RMS in vitro and in vivo through downregulating PAX3-FOXO1 activity, and combined knockdown of KDM3B and KDM1A phenocopied PFI-90 effects. Thus, we report novel KDM inhibitors with highest specificity for KDM3B. Its potent suppression of PAX3-FOXO1 activity can be exploited as a new therapeutic approach for FP-RMS and other transcriptionally driven cancers.