Project description:The jmjC-domain containing H3K4 histone demethylase JARID1B/KDM5B/PLU1 is over-expressed in human breast cancer and is a potential target for breast cancer treatment. To investigate the in vivo function of JARID1B, we developed a new strain of Jarid1b knockout mice and characterized the phenotypes in detail. Unlike previously reported knockout strains, the majority of our Jarid1b knockout mice are viable beyond embryonic and neonatal stages. Nonetheless, these mice exhibit decreased body weight, higher incidence of adult mortality and decreased female fertility. Furthermore, Jarid1b knockout mice show delayed mammary gland development. Mechanistically, loss of JARID1B leads to decreased serum estrogen levels and reduced proliferation of mammary epithelial cells in early puberty. In addition, in mammary epithelial cells, loss of JARID1B diminishes the expression of key regulators of mammary morphogenesis, including FOXA1, estrogen receptor α (ERα), and GATA3. Taken together, these results indicate that JARID1B positively regulates mammary ductal development through both extrinsic and cell-autonomous mechanisms. Compare gene expression of Jarid1B Knock Out and Wild type Mammary Epithelial Cells (MECs).
Project description:The telomeric amplicon at 8p12 is common in oestrogen receptor-positive (ER+) breast cancers. Array-CGH and expression analyses of 1172 primary breast tumours revealed that ZNF703 was the single gene within the minimal amplicon and was amplified predominantly in the Luminal B subtype. Amplification was shown to correlate with increased gene and protein expression and was associated with a distinct expression signature and poor clinical outcome. ZNF703 transformed NIH 3T3 fibroblasts, behaving as a classical oncogene, and regulated proliferation in human luminal breast cancer cell lines and immortalized human mammary epithelial cells. Manipulation of ZNF703 expression in the luminal MCF7 cell line modified the effects of TGFβ on proliferation. Overexpression of ZNF703 in normal human breast epithelial cells enhanced the frequency of in vitro colony-forming cells from luminal progenitors. Taken together, these data strongly point to ZNF703 as a novel oncogene in Luminal B breast cancer.
Project description:We quantified protein expression changes between epithelial and mesechymal stages in immortalized human mammary epithelial cells (HMLE). Epithelial–mesenchymal transition is induced by expressing an EMT-TF, Twist.
Project description:The WWOX gene has been implicated in human cancers, including breast cancer.The development and tumorigenesis between human and mouse mammary glands (MGs) share similar molecular details and signal transduction pathways. We established mouse line that specifically knockout the expression of WWOX gene in the MG epithelial cells (MECs) by crossing BK5-cre mice with our WWOX flox stain. In order to study the gene expression profile in the subpopulation MECs, we isolated the organoids from the 4th MGs of both BK5-cre +; WWOX flox/flox (KO) mice and their WT counterparts (BK5-cre -; WWOX flox/flox), 3 mice each genotype. The total RNA from the mouse MG organoids was extracted and purified by TRIzol/RNeasy Kit and their integrity was checked on Agilent RNA 6000 Nanochip. The goal is to identify the significant perturbation in tumorigenic pathways in these cells induced by WWOX ablation. Mammary gland epithelial organoids samples and gene expression profiles were deribed from three WWOX-KO mice (BK5-cre +; WWOX flox/flox) and from three WWOX-WT mice (BK5-cre -; WWOX flox/flox)
Project description:The goal of this study was to compare mRNA from mammary epithelial cells of 3 mammary-specific Nmi knockout FVB with corresponding wildtype control. This was performed to obtain clues to the signaling pathways that were impacted in the mammary epithelial cells upon knocking-out Nmi expression.
Project description:The jmjC-domain containing H3K4 histone demethylase JARID1B/KDM5B/PLU1 is over-expressed in human breast cancer and is a potential target for breast cancer treatment. To investigate the in vivo function of JARID1B, we developed a new strain of Jarid1b knockout mice and characterized the phenotypes in detail. Unlike previously reported knockout strains, the majority of our Jarid1b knockout mice are viable beyond embryonic and neonatal stages. Nonetheless, these mice exhibit decreased body weight, higher incidence of adult mortality and decreased female fertility. Furthermore, Jarid1b knockout mice show delayed mammary gland development. Mechanistically, loss of JARID1B leads to decreased serum estrogen levels and reduced proliferation of mammary epithelial cells in early puberty. In addition, in mammary epithelial cells, loss of JARID1B diminishes the expression of key regulators of mammary morphogenesis, including FOXA1, estrogen receptor α (ERα), and GATA3. Taken together, these results indicate that JARID1B positively regulates mammary ductal development through both extrinsic and cell-autonomous mechanisms.
Project description:Molecular profiling was used to classify mammary tumors that develop in MTB-IGFIR transgenic mice. It was determined that the primary mammary tumors (PMT), which develop due to elevated expression of the type I insulin-like growth factor receptor (IGF-IR) in mammary epithelial cells, most closely resemble murine tumors with basal-like or mixed gene expression profiles and with human basal-like breast cancers. Downregulation of IGF-IR transgene in MTB-IGFIR tumor-bearing mice leads to the regression of most of the tumors followed by tumor re-appearance in some of the mice. These tumors that re-appear following IGF-IR transgene downregulation do not express the IGF-IR transgene and cluster with murine mammary tumors that express a mesenchymal gene expression profile and with human claudin-low breast cancers. Therefore, IGF-IR overexpression in murine mammary epithelial cells induces mammary tumors with primarily basal-like characteristics while tumors that develop following IGF-IR downregulation express a gene signature that most closely resembles human claudin-low breast tumors.