Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:The epigenetic regulation, for example, DNA methylation, controls the development and differentiation of both tumor cells and immunocytes. Treatment with DNA demethylating agent (such as decitabine) has shown a dramatic clinical benefit in hematological malignancies and solid tumors. However, the influence of epigenetic therapy on host immune system remains unclear. To investigate the effects of low-dose decitabine therapy on T cells, We collected whole blood samples from two solid tumor patients pre and post low-dose decitabine therapy, and detected the expression profiles of PBMCs.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs. Two-condition experiment, KP MSCs vs. 3A6 MSCs.
Project description:Genome wide DNA methylation profiling of blood and biopsy samples from recurrent, platinum resistant epithelial ovarian cancer patients before and after treatment of decitabine in combination with carboplatin. The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs in PBMC (14 paired samples), tumor (8 paired samples) and ascites (6 paired samples).
Project description:Genome wide DNA methylation profiling of blood and biopsy samples from recurrent, platinum resistant epithelial ovarian cancer patients before and after treatment of decitabine in combination with carboplatin. The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs in PBMC (14 paired samples), tumor (8 paired samples) and ascites (6 paired samples). Bisulphite converted DNA from 56 samples were hybridised to the Illumina Infinium 27k Human Methylation Beadchip v1.2
Project description:Here we investigate the impact of epigenetic therapy with Decitabine in endocrine-resistant ER+ breast cancer by using patient-derived xenograft (PDX) models. Decitabine treatment restrained tumour growth, inhibited cell proliferation and resulted in significant loss of DNA methylation, particularly at enhancers and repetitive elements. Systematic integration of matched in situ Hi-C / PCHi-C, EPIC, RNA-seq and ChIP–seq datasets revealed widespread differences in epigenome regulation and enhancer-promoter communication with Decitabine. We find that loss of DNA methylation with Decitabine strongly affects the open (A) and closed (B) compartment structure and TAD boundary insulation. Our study identified and focused on key DNA methylation-dependent, enhancer ER binding sites that are activated in Decitabine-treated PDX tumours, enabling direct interactions between promoters and multiple distal enhancers, inducing expression of ER target genes and pathways. Overall, we demonstrate that epigenetic therapy inhibits tumour progression through to rewiring of ER-mediated 3D chromatin interactions and transcriptome programs. Our findings suggest that targeting the 3D epigenome with epigenetic therapies represents a promising strategy for anti-cancer treatment in ER+ endocrine resistant breast cancer patients.
Project description:Here we investigate the impact of epigenetic therapy with Decitabine in endocrine-resistant ER+ breast cancer by using patient-derived xenograft (PDX) models. Decitabine treatment restrained tumour growth, inhibited cell proliferation and resulted in significant loss of DNA methylation, particularly at enhancers and repetitive elements. Systematic integration of matched in situ Hi-C / PCHi-C, EPIC, RNA-seq and ChIP–seq datasets revealed widespread differences in epigenome regulation and enhancer-promoter communication with Decitabine. We find that loss of DNA methylation with Decitabine strongly affects the open (A) and closed (B) compartment structure and TAD boundary insulation. Our study identified and focused on key DNA methylation-dependent, enhancer ER binding sites that are activated in Decitabine-treated PDX tumours, enabling direct interactions between promoters and multiple distal enhancers, inducing expression of ER target genes and pathways. Overall, we demonstrate that epigenetic therapy inhibits tumour progression through to rewiring of ER-mediated 3D chromatin interactions and transcriptome programs. Our findings suggest that targeting the 3D epigenome with epigenetic therapies represents a promising strategy for anti-cancer treatment in ER+ endocrine resistant breast cancer patients.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
Project description:SPO11-promoted DNA double-strand breaks (DSBs) formation is a crucial step for meiotic recombination, and it is indispensable to detect the broken DNA ends accurately for dissecting the molecular mechanisms behind. Here, we report a novel technique, named DEtail-seq (DNA End tailing followed by sequencing), that can directly and quantitatively capture the meiotic DSB 3’ overhang hotspots at single-nucleotide resolution.