Project description:Analysis of human triple-negative breast cancer cells (TNBCs) which have high NF-kB activity. Proteins derived from NF-κB target genes might be molecular targets for cancer therapy. Results provide new insights into tumor proliferation mechanisms.
Project description:Breast cancer is genetically and clinically heterogeneous. Triple negative cancer (TNBC) is a subtype of breast cancer usually associated with poor outcome and lack of benefit from target therapy. A pathway analysis in a microarray study was performed using TNBC compared with non-triple negative breast cancer (non-TNBC). Overexpression of several Wnt pathway genes, such as frizzled homolog 7 (FZD7), Low density lipoprotein receptor-related protein 6 (LRP6) and transcription factor 7 (TCF7) has been observed in TNBC. Focus was given to the Wnt pathway receptor, FZD7. To validate its function, inhibition of FZD7 using FZD7shRNA was carried out. Notably decreased cell proliferation, suppressed invasiveness and colony formation in triple negative MDA-MB-231 and BT-20 cells were observed. Mechanism study indicated that these effects occurred through silencing the canonical Wnt signaling pathway, as evidenced by loss of nuclear accumulation of ï?¢-catenin and decreased transcriptional activity of TCF7. In vivo study revealed that FZD7shRNA significantly suppressed the tumor formation in xenotransplation mice due to decrease cell proliferation. Our finding suggests that FZD7 involved canonical Wnt signaling pathway is essential for tumorigenesis of TNBC. Thus, FZD7 may be a biomarker and a potential therapeutic target for triple negative breast cancer. 14 pretreatment non-triple negative breast tumors compare with 5 triple negative breast tumor.
Project description:Triple-negative breast cancer (TNBC) is an aggressive and highly lethal disease. Because of its heterogeneity and lack of hormone receptors or HER2 expression, targeted therapy is limited. Here, by performing a functional siRNA screening for 2-OG–dependent enzymes, we identified gamma-butyrobetaine hydroxylase 1 (BBOX1) as an essential gene for TNBC tumorigenesis. BBOX1 depletion inhibits TNBC cell growth while not affecting normal breast cells. Mechanistically, BBOX1 binds with the calcium channel inositol-1,4,5-trisphosphate receptor type 3 (IP3R3) in an enzymatic-dependent manner and prevents its ubiquitination and proteasomal degradation. BBOX1 depletion suppresses IP3R3-mediated endoplasmic reticulum calcium release, therefore impairing calcium-dependent energy-generating processes including mitochondrial respiration and mTORC1-mediated glycolysis, which leads to apoptosis and impaired cell-cycle progression in TNBC cells. Therapeutically, genetic depletion or pharmacologic inhibition of BBOX1 inhibits TNBC tumor growth in vitro and in vivo. Our study highlights the importance of targeting the previously uncharacterized BBOX1–IP3R3–calcium oncogenic signaling axis in TNBC.
Project description:The goal of this work was to identify all estrogen receptor beta target genes using RNA sequencing in MDA-MB-468 triple negative breast cancer cells engineered with inducible expression of full length estrogen receptor beta.
Project description:This SuperSeries is composed of the following subset Series: GSE21719: Identification of the receptor tyrosine kinase AXL in triple negative breast cancer as a novel target for the human miR-34a microRNA (miRNA study) GSE21832: Identification of the receptor tyrosine kinase AXL in triple negative breast cancer as a novel target for the human miR-34a microRNA (gene expression) Refer to individual Series
Project description:Analysis of human triple-negative breast cancer cells (TNBCs) which have high NF-kB activity. Proteins derived from NF-κB target genes might be molecular targets for cancer therapy. Results provide new insights into tumor proliferation mechanisms. Exp. 1: Mock MDA-MB-436 cells vs. MDA-MB-436 cells infected with Adenovirus-IkBaSR; Exp. 2: MDA-MB-436 cells infected with Adenovirus-GFP vs. MDA-MB-436 cells infected with Adenovirus-IkBaSR.
Project description:The goal of this work was to identify all estrogen receptor beta target genes using RNA sequencing in MDA-MB-468 triple negative breast cancer cells engineered with inducible expression of full length estrogen receptor beta. MDA-MB-468 breast cancer cells with inducible ERb expression (MDA-468-ERb cells) were treated in triplicate with vehicle (control, no ERb) or doxycycline (plus ERb) for 48 hr prior to treatment with 0.1% DMSO vehicle or 10 nM 17b-estradiol for 4 hr.
Project description:10 biopsies before treatment from triple negative patients with complete response were collected. Total RNA was extracted from tumor specimens and the whole transcriptome was quantified with Affymetrix HuGene1.1ST. The biopsies were classified into Good (major or complete) or Poor (absent or minor) therapeutic response subgroup. Whole genome expression of triple negative breast cancer tissues were measured before neoadjuvant chemotherapy
Project description:Triple Negative Breast Cancer (TNBC) is an aggressive subtype of breast cancer characterized by the absence of estrogen receptor alpha, progesterone receptor, and human epidermal growth factor receptor 2 (HER2). These receptors are well characterized and often serve as targets in breast cancer treatment. As a result, TNBCs are difficult to treat and have a high propensity to metastasize to distant organs. For these reasons, TNBCs are responsible for over 50% of all breast cancer mortalities while only accounting for 15% - 20% of breast cancer cases. However, estrogen receptor beta 1 (ERβ1) has emerged as a potential therapeutic target in the treatment of TNBCs. Using an in vivo xenograft preclinical mouse model with human TNBC, we found that expression of ERβ1 significantly reduced both primary tumor growth and metastasis in the animals. Moreover, TNBCs with elevated levels of ERβ1 showed reduction in epithelial-to-mesenchymal transition (EMT) markers and breast cancer stem cell (BCSC) markers, and increases in the expression of genes associated with inhibition of cancer cell invasiveness and metastasis, suggesting possible mechanisms underlying the antitumor activity of ERβ1. Treatment with ERβ1 agonist ligand often enhanced the suppressive activity of ERβ1, suggesting their potential utility in improving TNBC treatment. The findings enable understanding of the mechanisms by which ERβ impedes TNBC growth, invasiveness and metastasis and consideration of ways by which treatments involving ERβ might improve TNBC patient outcome.