Project description:Mutant p53 can acquires oncogenic properties supporting tumor growth, metastases and chemoresistance, by reprogramming cancer cell transcriptome, proteome and metabolome. To investigate what is the gene expression network regulated by mutant p53, we silenced its expression in MDA-MB-231 Triple Negative Breast Cancer (TNBC) cell line. We then performed gene expression profiling analysis using data obtained from RNA-seq of MDA-MB 231.
Project description:Dicer, RNase III endonuclease, is an essential enzyme in miRNA biogenesis that regulates target gene expression, and it has been reported that aberrant expressions of Dicer associate with the clinical outcomes of patients in various cancers. To explore the miRNA differencial expression regulated by Dicer in MDA-MB-231/E1A cells, the microarray profiling analysis was employed to conduct differentially expressed miRNAs in stable MDA-MB-231/vector, MDA-MB-231/E1A, and MDA-MB-231/E1A/shDicer cells.
Project description:To provide preliminary insights into metabolic and lipidomic characteristics in radioresistant triple-negative breast cancer (TNBC) cells and suggest potential therapeutic targets, we performed a comprehensive metabolic and lipidomic profiling of radioresistant MDA-MB-231 (MDA-MB-231/RR) TNBC cells and their parental cells using gas chromatography-mass spectrometry and nano electrospray ionization-mass spectrometry, followed by multivariate statistical analysis. Buthionine sulfoximine (BSO) and radiation were co-treated to radioresistant TNBC cells. The level of glutathione (GSH) was significantly increased, and the levels of GSH synthesis-related metabolites, such as cysteine, glycine, and glutamine were also increased in MDA-MB-231/RR cells. In contrast, the level of lactic acid was significantly reduced. In addition, reactive oxygen species (ROS) level was decreased in MDA-MB-231/RR cells. In the lipidomic profiles of MDA-MB-231/RR cells, the levels of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were significantly increased, whereas those of most of the phosphatidylinositol species were significantly decreased. BSO sensitized MDA-MB-231/RR cells to radiotherapy, which resulted in decreased GSH level and increased ROS level and apoptosis. Radioresistant TNBC cells showed distinct metabolic and lipidomic characteristics compared to their parental cells. We suggested activated GSH, PC, and PE biosynthesis pathways as potential targets for treating radioresistant TNBC cells. Particularly, enhanced radiosensitivity was achieved by inhibition of GSH biosynthesis in MDA-MB-231/RR cells.
Project description:LRP-1 (low-density lipoprotein receptor-related protein-1) receptor is a multifunctional endocytosis receptor that is part of the LDL receptor family. Due to its capacity to control the pericellular level of various growth factors and proteases, LRP-1 plays a crucial role in controlling the dynamics of the membrane proteome. LRP-1 overexpression in breast cancer, prompted us to take an interest in its involvement in tumor progression. An RNA interference strategy in MDA-MB-231 line was used, based on shRNA stable expression. In addition to integrated experimental strategies (in vitro and in vivo) through combined approaches of biochemistry, molecular biology, cell biology, multimodal preclinical imaging, proteomics allowed us to compare shLRP-1 MDA-MB-231 tumor conditioned media to shCtrl MDA-MB-231 tumor conditioned media in order to identify secreted molecular targets modulate by LRP-1 repression and thus provide a better understanding of its regulatory action within the TNBC microenvironment.
Project description:Identification of genes that are involved in self-seeding by comparing gene expression profiles between parental MDA-MB-231 cells and seeder cells (MDA-231-S1a and S1b) 2 replicates from each sample (parental MDA-MB-231, MDA-MB-231 S1a and MDA-MB-231 S1b) were analyzed
Project description:Dicer, RNase III endonuclease, is an essential enzyme in miRNA biogenesis that regulates target gene expression, and it has been reported that aberrant expressions of Dicer associate with the clinical outcomes of patients in various cancers. To explore the miRNA differencial expression regulated by Dicer in MDA-MB-231/E1A cells, the microarray profiling analysis was employed to conduct differentially expressed miRNAs in stable MDA-MB-231/vector, MDA-MB-231/E1A, and MDA-MB-231/E1A/shDicer cells. The four groups including vector control, E1A-expressing and Dicer knockdown in E1A-expressing MDA-MB-231 cells were harvested and RNA were isolated. Two independent experiments were performed for each group.
Project description:In previous studies, our research demonstrated that VNLG-152R exhibits inhibitory effects on Triple Negative Breast Cancer (TNBC) cells both in vitro and in vivo. The TNBC cell line MDA-MB-231 cells were treated with VNLG-152R. A total of 337 genes were differentially expressed when MDA-MB-231 cells were treated with 10 μM VNLG-152R for 24h; 259 genes were upregulated and 78 downregulated. Through proteome analyses, we discovered that VNLG-152R upregulates the expression of E3 ligase Synoviolin 1 (SYVN1), also called 3-hydroxy-3-methylglutaryl reductase degradation (HRD1) in TNBC cells. Moreover, we provide genetic and pharmacological evidence to demonstrate that SYVN1 mediates the ubiquitination and subsequent proteasomal degradation of MNK1/2, the only known kinases responsible for phosphorylating eIF4E. Phosphorylation of eIF4E being a rate-limiting step in the formation of the eIF4F translation initiation complex, the degradation of MNK1/2 by VNLG-152R and its analogs impedes dysregulated translation in TNBC cells, resulting in the inhibition of tumor growth. Importantly, our findings were validated in vivo using TNBC xenograft models derived from MDA-MB-231, MDA-MB-468, and MDA-MB-453 cell lines, representing different racial origins and genetic backgrounds. These xenograft models, which encompass TNBCs with varying androgen receptor (AR) expression levels, were effectively inhibited by oral administration of VNLG-152R and its deuterated analogs in NRG mice.
Project description:Identification of genes that are involved in self-seeding by comparing gene expression profiles between parental MDA-MB-231 cells and seeder cells (MDA-231-S1a and S1b)
Project description:microRNAs have been shown to be involved in the pathogenesis of TNBC as important regulators of cell proliferation and apoptosis. However, whether the activation of retinoic acid receptor alpha (RARα), a transcription factor, is involved in mediating transcriptional regulation of microRNAs remains elusive. Here, we investigated the differentially expressed miRNAs in triple negative breast cancer cell line MDA-MB-231 overexpressing a phosphorylation-defective mutant RARαS77A, which mimicked activated RARα, in comparison to non-transfected control cells.
Project description:Identification of MUC4-associated expression of genes by comparing MUC4 knockdown (MDA-MB-231-shMUC4) and control (MDA-MB-231-SCR).