Project description:Triple-negative breast cancer (TNBC) is an aggressive and highly lethal disease. Due to its heterogeneity and lack of hormone receptors or HER2 expression, it is critical to identify novel therapeutic targets in TNBC. Analysis of copy number and gene expression in tumors from The Cancer Genome Atlas suggested that ZHX2 was amplified and overexpressed in breast cancer patients. Correspondingly, we found that ZHX2 was highly expressed in TNBC cell lines and TNBC patient tissues. Functionally, depletion of ZHX2 inhibited TNBC cell growth and invasion in vitro, orthotopic tumor growth and spontaneous lung metastasis in vivo. Mechanistically, ZHX2 bound with Hypoxia inducible factor (HIF) family members and positively regulated HIF1 activity in TNBC by using loss-of-function or gain-of-function studies. Our integrated ChIP-Seq and gene expression profiling demonstrated that ZHX2 co-occupied with HIF1 on transcriptionally active promoters marked by H3K4me3 and H3K27Ac, therefore promoting gene expression. Furthermore, structural simulation and functional studies revealed that multiple residues (R491, R581 and R674) are important in regulating the phenotype of ZHX2 on TNBC tumorigenic potential, which correspond with their roles on controlling HIF1 activity in TNBC cells. These studies establish that ZHX2 activates oncogenic HIF1 signaling, therefore serving as a potential therapeutic target for TNBC.
Project description:Triple-negative breast cancer (TNBC) has a relatively aggressive biological behavior and poor outcome. Our published study showed that PAI-1 could induce the migration and metastasis of TNBC cells. However, the underlying mechanism by which PAI-1 regulates TNBC metastasis has not been addressed. Using microarray analysis of lncRNA expression profiles, we identified a lncRNA SOX2-OT, which is by induced by PAI-1 and could function as an oncogenic lncRNA in TNBC.
Project description:The aim of this study was evaluate the transcriptome changes in the comparison between triple negative tumors with increased SPARC expression and triple negative tumors with decreased SPARC expression according to Nagai et al., 2011 (Breast Cancer Res Treat (2011) 126:1–14) The results generated could be of particular interest to better define the prognostic impact of SPARC expression in triple negative breast tumors
Project description:Background: This study focuses on the analysis of miRNAs expression data in a cohort of 181 well characterised breast cancer samples composed primarily of triple-negative (ER/PR/HER2-negative) tumours with associated genome-wide DNA and mRNA data, extensive patient follow-up and pathological information. Results: We identified 7 miRNAs with a prognostic role in the triple-negative tumours and an additional 8 prognostic miRNAs when the analysis was extended to the set of all ER-negative cases. miRNAs linked to an unfavourable prognosis were associated with a broad spectrum of motility mechanisms involved in the invasion of stromal tissues, such as cell-adhesion, growth factor-mediated signalling pathways, interaction with the extracellular matrix and cytoskeleton remodelling. When we compared different intrinsic molecular subtypes we found 46 miRNAs that were specifically expressed in one or more intrinsic subtypes. Integrated genomic analyses indicated these miRNAs to be largely influenced by DNA genomic aberrations and to exert a silencing effect on their targets through transcriptional down-regulation. Among others, our analyses highlighted the role of miR17-92 and miR-106b-25, two polycistronic miRNA clusters with known oncogenic functions. We showed that their basal-like specific up-regulation is influenced by increased DNA copy number and contributes to the transcriptional phenotype and the activation of oncogenic pathways in basal-like tumours.Conclusions: This is the first study analysing miRNA, mRNA and DNA data in integration with pathological and clinical information, in a large and well-annotated cohort of triple-negative breast cancers. It provides a conceptual framework, as well as integrative methods and system-level results to elucidate the role of miRNAs as biomarkers and modulators of oncogenic processes in these types of tumours. 181 breast tumour samples were analyzed, extracted from 173 patients. For the great majority of patients (165) only one sample was extracted, while for 8 patients two samples were extracted (biological replicates).
Project description:This phase I trial is studying the side effects and best dose of giving 7-hydroxystaurosporine together with irinotecan hydrochloride in treating patients with metastatic or unresectable solid tumors, including triple-negative breast cancer (currently enrolling only patients with triple-negative breast cancer since 6/8/2007). Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Giving 7-hydroxystaurosporine together with irinotecan hydrochloride may help kill more cancer cells by making tumor cells more sensitive to the drug.
Project description:Development of a reliable method for human triple-negative breast cancer organotypic culture: Improving imaging and genomic studies in 3D cultures The primary objectives of this study are to develop an advanced three-dimensional cell culture system to better model the tumor microenvironment in triple-negative breast cancer (TNBC), analyze the differences in molecular and cellular behavior between two-dimensional (2D) and 3D cultures, and investigate the impact of these differences on key oncogenic signaling pathways, specifically PI3K and β-catenin.
Project description:NEK2 is a mitotic kinase that is upregulated and mislocalized in the nucleus of human cancer cells. NEK2 modulates expression and activity of both transcription and splicing factors in cancer cells, nevertheless whether this kinase affects transcriptome regulation genome widely and whether this activity concurs to its oncogenic activity is still unknown. Herein, by high-throughput RNA sequencing analysis of MDA-MB-231 cells transiently silenced for NEK2 we uncover an extensive modulation of triple-negative breast cancer cell transcriptome by this kinase.