Project description:Three triple negative breast cancer cell lines (MDAMB231, SUM159, and HCC1806) were treated with small molecule inhibitors (JQ1, BET bromodomain inhibitor; GSK2801, BAZ2A/B bromodomain inhibitor) or BAZ siRNA alone and in combination with JQ1 for 48 hours
Project description:Three triple negative breast cancer cell lines (MDAMB231, SUM159, and HCC1806) were treated with small molecule inhibitors (JQ1, BET bromodomain inhibitor; GSK2801, BAZ2A/B bromodomain inhibitor) alone and in combination for 72 hours
Project description:This study aimed to investigate whether the BET inhibitor JQ1 could alter the hypoxia-induced upregulation of gene expression and have an anti-tumour effect associated with this mechanism. We showed JQ1 downregulates 44% of hypoxia upregulated genes, including CA9 and VEGF-A. We demonstrated that JQ1 reduces triple receptor negative breast cancer (TNBC) tumour growth in monolayer and spheroid (3D) cell culture.
Project description:To obtain the gene expression profiles of triple-negative breast cancer MDA-MB-231 cells and liver cancer HepG2 cells perturbed by the BET inhibitor JQ1, we treated MDA-MB-231 and HepG2 cells with either DMSO (control) or 10 μM JQ1 for 24 hours. By comparing the expression profiles of DMSO-treated cells with those treated with JQ1, we can identify the genes affected by JQ1.
Project description:Triple negative breast cancer (TNBC) is a heterogeneous and clinically aggressive disease for which there is no targeted therapy. Here we report the preferential and high sensitivity of TNBCs to BET bromodomain inhibitors such as JQ1 manifested by cell cycle arrest in early G1, apoptosis, and induction of markers of luminal epithelial differentiation in vitro and in vivo. The sensitivity of TNBC and other tumor types to BET inhibition establishes a rationale for clinical investigation, and a motivation to understand mechanisms of resistance. After engendering acquired resistance to BET inhibition in previously sensitive TNBCs, we utilized integrative approaches to identify a unique mechanism of epigenomic resistance to this epigenetic therapy. Resistant cells remain dependent on BRD4, confirmed by RNA interference. However, TNBC cells adapt to BET bromodomain inhibition by re-recruitment of unmutated BRD4 to super-enhancers, now in a bromodomain-independent manner. Proteomic studies of resistant TNBC identify hyper-phosphorylation of BRD4 and strong association with MED1. Together, these studies provide a rationale for BET inhibition in TNBC and argue for combination strategies to anticipate clinical drug resistance. ChIP-seq in parental and JQ1 resistant triple negative breast cancer (TNBC) in response to DMSO or JQ1 treatment
Project description:Purpose: The BET family protein BRD4 is an important anti-tumor target and is highly expressed in breast cancer. However, BET inhibitors are susceptible to drug resistance. The aim of this study is to explore the mechanism of BET inhibitor JQ-1 combined with cardamonin in the anti-invasion and metastasis of triple-negative breast cancer. Methods: triple-negative breast cancer cells mRNA of DMSO (Control), JQ-1,cardamonin and combined groups were progressed with deep sequencing, in triplicate through Illumina sequencing platform (HiSeqTM 2500). Genes with adjusted P-value < 0.01 and |foldChange| > 2 were defined as differentially expressed genes (DEGs) and subjected to the following GO and KEGG enrichment. qRT-PCR was performed to validate several essential genes using QuantStudio 5 (Thermo Fisher) and SYBR Green assays. Results: As an inhibitor of mTOR, Cardamonin(CAR) can inhibit the proliferation of tumors. Research have found that BET inhibitor can affect the function of a large number of genes by regulating the epigenome, which plays an important role in a variety of diseases. In this study we explored the JQ1 which is a BRD4 protein inhibitor can inhibit the proliferation and metastasis of MDA-MB-231 cells in triple-negative breast cancer cell lines, and this phenomenon can be significantly enhanced when CAR is combined with JQ-1, and the same results are shown in mouse tumor formation experiments and triple-negative breast cancer organoids. At the same time, RNA-seq was performed in MD1-MB-231 cells to explore the changes of specific molecular signaling pathways. We have mapped over 40 million sequence reads to the MDA-MB-231 cell line genome in each specimen.Compared with the control group, CAR and JQ1, the combination group has significantly enriched gene expression. KEGG and GO enrichment analysis indicate that the combination group showed a series of biological processes such as macroautophagy, negative regulation of cell growth, lipid catabolic process, which led to decreased cell viability and decreased proliferation and metastasis ability. Conclusions: In this study, we demonstrated that JQ-1 combined with cardamomin could inhibit the invasion and metastasis of triple-negative breast cancer MDA-MB-231 cells, induce cell cycle arrest and promote cell apoptosis. The results of RNA-Seq were consistent with our in vitro and in vivo experiments, which demonstrated that the combination of JQ-1 and cardamonin effectively inhibited the proliferation, invasion and metastasis of MDA-MB-231 cells.
Project description:To study the effect of BET inhibition on gene expression in triple-negative breast cancer cells, we treated MDA-MB-231 and HCC70 cells with vehicle or the prototypical BET inhibitor, JQ1, for 72 hours. By comparing the expression profiles of vehicle-treated versus JQ1-treated cells, we can identify genes that respond to BET inhibition. The Affymetrix Human Gene 2.0. St Microarray were processed with RMA (robust multichip average algorithm) as implemented in Bioconductor package oligo, where background subtraction, quantile normalization and summarization (via median-polish) was accomplished. The top differentially expressed genes were identified using empirical Bayesian procedure of limma package. FDR method was selected to adjust the p-values for multiple testing.
Project description:Triple negative breast cancer (TNBC) is a heterogeneous and clinically aggressive disease for which there is no targeted therapy. Here we report the preferential and high sensitivity of TNBCs to BET bromodomain inhibitors such as JQ1 manifested by cell cycle arrest in early G1, apoptosis, and induction of markers of luminal epithelial differentiation in vitro and in vivo. The sensitivity of TNBC and other tumor types to BET inhibition establishes a rationale for clinical investigation, and a motivation to understand mechanisms of resistance. After engendering acquired resistance to BET inhibition in previously sensitive TNBCs, we utilized integrative approaches to identify a unique mechanism of epigenomic resistance to this epigenetic therapy. Resistant cells remain dependent on BRD4, confirmed by RNA interference. However, TNBC cells adapt to BET bromodomain inhibition by re-recruitment of unmutated BRD4 to super-enhancers, now in a bromodomain-independent manner. Proteomic studies of resistant TNBC identify hyper-phosphorylation of BRD4 and strong association with MED1. Together, these studies provide a rationale for BET inhibition in TNBC and argue for combination strategies to anticipate clinical drug resistance. RNA-Seq in parental and JQ1 resistant triple negative breast cancer (TNBC) in response to DMSO or JQ1 treatment over time
Project description:Triple negative breast cancer (TNBC) is a heterogeneous and clinically aggressive disease for which there is no targeted therapy. Here we report the preferential and high sensitivity of TNBCs to BET bromodomain inhibitors such as JQ1 manifested by cell cycle arrest in early G1, apoptosis, and induction of markers of luminal epithelial differentiation in vitro and in vivo. The sensitivity of TNBC and other tumor types to BET inhibition establishes a rationale for clinical investigation, and a motivation to understand mechanisms of resistance. After engendering acquired resistance to BET inhibition in previously sensitive TNBCs, we utilized integrative approaches to identify a unique mechanism of epigenomic resistance to this epigenetic therapy. Resistant cells remain dependent on BRD4, confirmed by RNA interference. However, TNBC cells adapt to BET bromodomain inhibition by re-recruitment of unmutated BRD4 to super-enhancers, now in a bromodomain-independent manner. Proteomic studies of resistant TNBC identify hyper-phosphorylation of BRD4 and strong association with MED1. Together, these studies provide a rationale for BET inhibition in TNBC and argue for combination strategies to anticipate clinical drug resistance. Chem-Seq in parental and JQ1 resistant triple negative breast cancer (TNBC)