Project description:We report the application of in situ Hi-C technology to 40 colorectal cancer patients and 10 paired-normal tissue to identify CRC specific changes in 3D chromatin structure. The chromatin contact matrices were generated by the sequencing data and image processing/deep learning-based algorithm was proposed to identify long-range abnormal chromatin interaction patterns in the contact matrices. The tumor specific 3D chromatin structure changes and the enhancer-promoter rewiring mediated by the identified chromatin structure changes were analyzed. The complex chromosome-wide rearrangements such as chromothripsis and its effect to 3D chromatin structure were also observed.
Project description:Acute myeloid leukemia (AML) is a set of heterogeneous myeloid malignancies hallmarked by mutations in epigenetic modifiers, transcription factors and kinases that can cause epigenetic reshaping. It is unclear whether those mutations drive chromatin 3D structure alteration and contribute to oncogenic dysregulation in AML. By performing Hi-C and whole genome sequencing in 21 primary AML and healthy donors’ samples, we identified recurrent AML- or subtype-specific alteration of compartments, TADs, and chromatin loops. To study the impact on gene regulation, we performed RNA-Seq, ATAC-Seq and CUT&TAG for CTCF, H3K27ac, and H3K27me3 in the same samples. We observed dysregulation of many AML-related genes, represented by MYCN, MEIS1, WT1, ERG, MYC GATA3, BCL11B and IKZF2, intimately linked to the recurrent gain of loops and switch of compartment or TAD, alongside acquisition of AML-specific enhancer or repressor. Further, we profiled structure variations using WGS and Hi-C data to reconstruct the cancer 3D genome, by which we identified structure variation-induced neo-loops and enhancer-hijacking events. Furthermore, through conducting whole genome bisulfite sequencing in patient samples, we found altered methylation correlated with A/B compartment switch, and loss of CTCF insulation due to hypermethylation, leading to extensive gain of loops in AML. By treating the AML cells with DNA hypomethylation agent 5-azacytidine, the altered chromatin structure and gene expression can be restored, with switched compartment reverted and gained loops dissociated, alongside compromised AML cell proliferation, overall providing insights into AML treatment through therapeutic restoration of chromatin structure.
Project description:Although the Hi-C maps in cultured immune cell has been reported, there still lacks 3D landscape of human primary monocytes. The peripheral blood from two health people and two SLE patients was collected and CD14+ monocytes were selected to perform Hi-C, RNA-seq, ATAC-seq and ChIP-seq. The raw data of THP1 cell Hi-C library was also used in comparison. We firstly presented the 3D genome structure heterogeneity in human primary monocytes. Significantly diversity of chromatin interaction in HLA complex region might regulates many immunologic processes. The chromatin loop regulation around CD16 and its relevant expression pattern indicated the CD16 associated monocyte functions are dominated regulated by this variable TAD boundary.
Project description:Relapsed pediatric B-cell acute lymphoblastic leukemia (B-ALL) remains one of the leading causes of cancer mortality in children. Up to 20% of children will suffer relapse and face a poor prognosis. Our recent work on the evolution of the epigenetic landscape from diagnosis to relapse demonstrates both substantial diversity in the chromatin landscape as well as shared relapse-specific superenhancer activation, highlighting the importance of chromatin changes in disease progression. However, there is a gap in our understanding of B-ALL progression through the lens of three-dimensional (3D) chromosome topology. To uncover 3D chromatin architecture-related mechanisms underlying drug resistance in B-ALL, we performed Hi-C, ATAC-seq, and RNA-seq on 12 matched primary pediatric leukemia specimens at diagnosis and relapse. Mapping of structural variations (SVs) using Hi-C data revealed previously unidentified stable, diagnosis-specific, and relapse-specific SVs providing further evidence for clonal evolution as a mechanism for drug resistance. Moreover, Hi-C analysis revealed genome wide chromatin remodeling specifically in terms of A/B compartments, TAD interactivity, and chromatin loops. Integration with ATAC-seq and RNA-seq datasets revealed strong correlation with both gene expression and chromatin accessibility. Additionally, we identified recurrent A/B compartments and TAD interactivity changes across the patient cohort for which we were able to demonstrate a crucial role in the clonal evolution of B-ALL. Shared changes in 3D genome organization drive the expression of genes/pathways previously implicated in drug resistance as well. Lastly, enrichment analysis revealed key upstream regulators of 3D genome architecture in B-ALL disease progression. These results extend the landscape of genetic alterations in relapsed B-ALL through the addition of the 3D genomic landscape and identify a breadth of novel therapeutic targets.
Project description:Acute myeloid leukemia (AML) is a set of heterogeneous myeloid malignancies hallmarked by mutations in epigenetic modifiers, transcription factors and kinases that can cause epigenetic reshaping. It is unclear whether those mutations drive chromatin 3D structure alteration and contribute to oncogenic dysregulation in AML. By performing Hi-C and whole genome sequencing in 21 primary AML and healthy donors’ samples, we identified recurrent AML- or subtype-specific alteration of compartments, TADs, and chromatin loops. To study the impact on gene regulation, we performed RNA-Seq, ATAC-Seq and CUT&TAG for CTCF, H3K27ac, and H3K27me3 in the same samples. We observed dysregulation of many AML-related genes, represented by MYCN, MEIS1, WT1, ERG, MYC GATA3, BCL11B and IKZF2, intimately linked to the recurrent gain of loops and switch of compartment or TAD, alongside acquisition of AML-specific enhancer or repressor. Further, we profiled structure variations using WGS and Hi-C data to reconstruct the cancer 3D genome, by which we identified structure variation-induced neo-loops and enhancer-hijacking events. Furthermore, through conducting whole genome bisulfite sequencing in patient samples, we found altered methylation correlated with A/B compartment switch, and loss of CTCF insulation due to hypermethylation, leading to extensive gain of loops in AML. By treating the AML cells with DNA hypomethylation agent 5-azacytidine, the altered chromatin structure and gene expression can be restored, with switched compartment reverted and gained loops dissociated, alongside compromised AML cell proliferation, overall providing insights into AML treatment through therapeutic restoration of chromatin structure.
Project description:Acute myeloid leukemia (AML) is a set of heterogeneous myeloid malignancies hallmarked by mutations in epigenetic modifiers, transcription factors and kinases that can cause epigenetic reshaping. It is unclear whether those mutations drive chromatin 3D structure alteration and contribute to oncogenic dysregulation in AML. By performing Hi-C and whole genome sequencing in 21 primary AML and healthy donors’ samples, we identified recurrent AML- or subtype-specific alteration of compartments, TADs, and chromatin loops. To study the impact on gene regulation, we performed RNA-Seq, ATAC-Seq and CUT&TAG for CTCF, H3K27ac, and H3K27me3 in the same samples. We observed dysregulation of many AML-related genes, represented by MYCN, MEIS1, WT1, ERG, MYC GATA3, BCL11B and IKZF2, intimately linked to the recurrent gain of loops and switch of compartment or TAD, alongside acquisition of AML-specific enhancer or repressor. Further, we profiled structure variations using WGS and Hi-C data to reconstruct the cancer 3D genome, by which we identified structure variation-induced neo-loops and enhancer-hijacking events. Furthermore, through conducting whole genome bisulfite sequencing in patient samples, we found altered methylation correlated with A/B compartment switch, and loss of CTCF insulation due to hypermethylation, leading to extensive gain of loops in AML. By treating the AML cells with DNA hypomethylation agent 5-azacytidine, the altered chromatin structure and gene expression can be restored, with switched compartment reverted and gained loops dissociated, alongside compromised AML cell proliferation, overall providing insights into AML treatment through therapeutic restoration of chromatin structure.