Project description:Cancer progression is associated with alterations of epigenetic regulators such as histone-lysine demethylases 4 (KDM4)2-5. During breast cancer therapy, classical treatments fail to address resistant cancer stem cell populations6-10. Here, we identified a novel KDM4 inhibitor (KDM4(i)) with unique preclinical characteristics. KDM4(i) is a highly potent pan KDM4 inhibitor that specifically blocks the demethylase activity of KDM4A, B, C, and D but not that of the other members of the KDM family. We validated the KDM4(i) anti-tumoral properties under conditions recapitulating patient tumors. Therefore, we established a method to isolate and grow triple-negative breast cancer stem cells (BCSCs) from individual patient tumors after neoadjuvant chemotherapy. Limiting dilution orthotopic xenografts of these BCSCs faithfully regenerate original patient tumor histology and gene expression. KDM4(i) blocks proliferation, sphere formation and xenograft tumor growth of BCSCs. Importantly, KDM4(i) abrogates expression of EGFR, a driver of therapy-resistant triple-negative breast tumor cells11, via inhibition of the KDM4A demethylase activity. Taken together, we present a unique BCSC culture system as a basis for therapeutic compound identification and demonstrate that KDM4 inhibition is a new therapeutic strategy for the treatment of triple-negative breast cancer.

2018-04-10 | GSE95042 | GEO

Identification of ChIP-seq and RIME grade antibodies for Estrogen Receptor alpha

Project description:Estrogen Receptor alpha (ERα) is a key driver of most breast cancers, and it is the target of endocrine therapies used in the clinic to treat women with ERα positive (ER+) breast cancer. The two methods ChIP-seq (chromatin immunoprecipitation coupled with deep sequencing) and RIME (Rapid Immunoprecipitation of Endogenous Proteins) have greatly improved our understanding of ERα function during breast cancer progression and in response to anti-estrogens. A critical component of both ChIP-seq and RIME protocols is the antibody that is used to pull down the bait protein. To date, most of the ChIP-seq and RIME experiments for the study of ERα have been performed using the sc-543 antibody from Santa Cruz Biotechnology. However, this antibody has been discontinued, thereby severely impacting the study of ERα in normal physiology as well as diseases such as breast cancer and ovarian cancer. Here, we compare the sc-543 antibody with other commercially available antibodies, and we show that 06-935 (EMD Millipore) and ab3575 (Abcam) antibodies can successfully replace the sc-543 antibody for ChIP-seq and RIME experiments.

2019-03-21 | PXD012930 | Pride

Genome-wide maps of H3K9me3 in hematopoietic stem cells from Kdm4a, b, c triple knockout mice

Project description:The KDM4/JMJD2 are H3K9- and H3K36- specific demethylases, which are considered promising therapeutic targets for the treatment of acute myeloid leukemia (AML) harboring MLL-translocations. Here, we investigate the long-term effects of depleting KDM4 activity on normal hematopoiesis to probe potential side effects of continuous inhibition of these enzymes. Utilizing conditional Kdm4a/Kdm4b/Kdm4c triple-knockout mice we show that KDM4 activity is required for hematopoietic stem cell (HSC) maintenance in vivo. The knockout of the KDM4 demethylases leads to accumulation of H3K9me3 on transcription start sites and the corresponding downregulation of expression of several genes in hematopoietic stem cells. We show that two of these genes, Taf1b and Nom1, are essential for the maintenance of hematopoietic cells. Taken together, our results show that the KDM4 demethylases are required for the expression of genes essential for the long-term maintenance of normal hematopoiesis.

2019-04-02 | GSE129156 | GEO

RNA-seq using RNA from KDM4 WT and Knockout haematopoietic stem cells

2019-04-02 | GSE129137 | GEO

KDM4 inhibition targets breast cancer stem cells [RNA-Seq]

Project description:We treated breast cancer stemm cells (BCSC) with a KDM4 inhibitor

2017-12-15 | GSE95293 | GEO

GNPS - JAK-STAT signaling in inflammatory breast cancer enables chemotherapy-resistant cell states

Project description:Inflammatory breast cancer (IBC) is a difficult-to-treat disease with poor clinical outcomes due to high risk of metastasis and resistance to treatment. We previously described a CD44+CD24-pSTAT3+ cancer cell subpopulation with stem cell-like features in breast cancer that is dependent on JAK/STAT3 signaling. Here we report that CD44+CD24- cells are the most frequent cell-type in IBC and are commonly pSTAT3+. Combination of JAK/STAT3 inhibition with paclitaxel decreased IBC xenograft growth more than either agent alone. We developed and characterized IBC cell lines resistant to paclitaxel and doxorubicin to mimic therapeutic resistance in patients. Multi-omic profiling of parental and resistant cells revealed genes associated with lineage identity and inflammation were enriched in chemotherapy resistant derivatives. Integrated pSTAT3 ChIP-seq and RNA-seq analyses showed pSTAT3 regulates genes related to inflammation and epithelial to mesenchymal transition (EMT) in resistant cells, as well as PDE4A, a cAMP-specific phosphodiesterase. Metabolomic characterization identified elevated cAMP signaling and CREB as a candidate therapeutic target in IBC. We also investigated cellular dynamics and heterogeneity at the single cell level during chemotherapy and acquired resistance by CyTOF and single cell RNA-seq. We identified mechanisms of resistance including a shift from luminal to basal/mesenchymal cell states through selection for rare pre-existing subpopulations or an acquired change. Lastly, we showed that combination treatment with paclitaxel and JAK/STAT3 inhibition prevented the emergence of this more mesenchymal chemo-resistant subpopulation. Our results provide mechanistic rational for combination of chemotherapy with inhibition of JAK/STAT3 signaling as a new more effective therapeutic strategy in IBC.

2022-11-04 | MSV000090647 | GNPS

KDM4 inhibition targets breast cancer stem cells [ChIP-Seq]

Project description:We treated breast cancer stemm cells (BCSC) with a KDM4 inhibitor or performed knockdown of KDM4A

2017-12-15 | GSE95190 | GEO