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 Forkhead family of transcription factors comprises numerous members and is implicated in various cellular functions, including cell growth, apoptosis, migration and differentiation.In this study we identified the Forkhead factor FoxQ1 as increased in expression during TGF-beta1 induced changes in epithelial differentiation, suggesting functional roles of FoxQ1 for epithelial plasticity.The repression of FoxQ1 in mammary epithelial cells led to a change in cell morphology characterized by an increase in cell size, pronounced cell-cell contacts and an increased expression of several junction proteins (e.g. E-cadherin). In addition, FoxQ1 knock-down cells revealed rearrangements in the actin-cytoskeleton and slowed down cell cycle G1-phase progression.Furthermore, repression of FoxQ1 enhanced the migratory capacity of coherent mammary epithelial cells.Gene expression profiling of NM18 cells indicated that FoxQ1 is a relevant downstream mediator of TGF-beta1 induced gene expression changes. This included the differential expression of transcription factors involved in epithelial plasticity, e.g. Ets-1, Zeb1 and Zeb2.In summary, this study has elucidated the functional impact of FoxQ1 on epithelial differentiation
Project description:In this experiment, we have tested the effect of microRNA-203 as a potential differentiation inducer in breast cancer organoids, derived from the PyMT mouse model. MMTV-PyVT transgenic mice express the Polyoma Virus middle T antigen under the direction of the mouse mammary tumor virus promoter/enhancer. Hemizygous MMTV-PyMT females develop palpable mammary tumors which metastasize to the lung. These mice have high penetrance of early onset of mammary cancer compared to other mammary tumor models. PyMT mice were crossed with miR-203 knock-in mice, where miR-203 expression is induced upon DOX treatment. Thus, organoids derived from the mammary gland tumors of such mouse model where evaluated in vitro. miR-203 expression was therefore induced by Doxycycline in vitro, and compared to other well-defined differentiation media for breast cancer tissue, such as the mammary epithelial cell culture media and kit (CC-2551B; Lonza).
Project description:ErbB2-induced mouse mammary tumors can originate from different mammary epithelial cells, including both basal epithelial cells and luminal progenitors. Here we used the tumors from basal cells or luminal progenitors to compare the difference in transcripts. RNA was isolated from basal cell- or luminal progenitor-derived tumors for Illumina whole mouse transcript array analysis. Three paired tumors were analyzed.
Project description:The GATA-type zinc-finger transcription factor TRPS1 has been implicated in breast cancer. However, its precise role remains unclear, as both amplifications and inactivating mutations in TRPS1 have been reported. Here, we used in vitro and in vivo loss-of-function approaches to dissect the role of TRPS1 in mammary gland development and invasive lobular breast carcinoma, which is hallmarked by functional loss of E-cadherin. We show that TRPS1 is essential in mammary epithelial cells, since TRPS1-mediated suppression of interferon signaling promotes in vitro proliferation and lactogenic differentiation. Similarly, TRPS1 expression is indispensable for proliferation of mammary organoids and in vivo survival of luminal epithelial cells during mammary gland development. However, the consequences of TRPS1 loss are dependent on E-cadherin status, as combined inactivation of E-cadherin and TRPS1 causes persistent proliferation of mammary organoids and accelerated mammary tumor formation in mice. Together, our results demonstrate that TRPS1 can function as a context-dependent tumor suppressor in breast cancer, whilst being essential for growth and differentiation of normal mammary epithelial cells.
Project description:The GATA-type zinc-finger transcription factor TRPS1 has been implicated in breast cancer. However, its precise role remains unclear, as both amplifications and inactivating mutations in TRPS1 have been reported. Here, we used in vitro and in vivo loss-of-function approaches to dissect the role of TRPS1 in mammary gland development and invasive lobular breast carcinoma, which is hallmarked by functional loss of E-cadherin. We show that TRPS1 is essential in mammary epithelial cells, since TRPS1-mediated suppression of interferon signaling promotes in vitro proliferation and lactogenic differentiation. Similarly, TRPS1 expression is indispensable for proliferation of mammary organoids and in vivo survival of luminal epithelial cells during mammary gland development. However, the consequences of TRPS1 loss are dependent on E-cadherin status, as combined inactivation of E-cadherin and TRPS1 causes persistent proliferation of mammary organoids and accelerated mammary tumor formation in mice. Together, our results demonstrate that TRPS1 can function as a context-dependent tumor suppressor in breast cancer, whilst being essential for growth and differentiation of normal mammary epithelial cells.
Project description:Multiple EMT-promoting/inhibiting transcription factors have been identified including Snail, Zeb1 and Ovol2. To understand differential roles of these factors, we performed gene expression profiling by RNA-seq upon Snail-/Zeb1-induced EMT or Ovol2-induced MET in human mammary epithelial MCF10A cells.
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.