Project description:We developed a post-menopausal orthotopic ER+ breast cancer model that we used to investigate mechanisms of obesity mediated lung metastases. Obesity altered the immune cell composition and function in the primary tumor microenvironment. To identify tumor-derived genes associated with obesity mediated lung metastases we performed RNASeq on tumors grown in lean vs obese mice. From these results we identified a hepatocyte growth factor (HGF)-c-Met (HGF receptor)-CCL2 loop recruiting metastasis-promoting cells.
Project description:Obesity is a major risk factor for adverse outcomes in breast cancer. Maguire, Ackerman et al. reveal Gatm and Acsbg1 as molecular regulators of obesity-driven breast cancer progression. They further show that in obesity creatine is a key metabolite in the crosstalk between adipocytes and breast tumors.
Project description:Brain metastasis is one of the most feared complications of cancer and the most common intracranial malignancy in adults. Its underlying mechanisms remain unknown. From breast cancer patients with metastatic disease we isolated cell populations that aggressively colonize the brain. Transcriptomic analysis of these cells yielded overlapping gene sets whose expression is selectively associated with brain metastasis. The expression of seventeen of these genes in primary breast tumors is associated with brain relapse in breast cancer patients. Some of these genes are also associated with metastasis to lung but not to liver, bone or lymph nodes, providing a molecular basis for the long-observed clinical link between brain and lung metastasis. Among the functionally validated brain metastasis genes, the cyclooxygenase COX-2, the EGFR ligand HB-EGF, and the brain-specific α2-6 sialyltransferase ST6GALNAC5 mediate cancer cell passage through the blood-brain barrier. Other brain metastasis genes encode inflammatory factors and brain-specific proteolytic regulators, suggesting a multifaceted program for breast cancer colonization of the brain.
Project description:BRMS1L (breast cancer metastasis suppressor 1 likeM-oM-<M-^LBRMS1-like) is a component of the SIN3A-HDAC corepressor complex that suppresses target gene transcription. Here, we show that reduced BRMS1L in breast cancer tissues is associated with tumor metastasis and poor patient survival. Functionally, BRMS1L inhibits migration and invasion of breast cancer cells by inhibiting epithelial-mesenchymal transition (EMT). These effects are mediated by epigenetic silencing of FZD10, a receptor for Wnt signaling, by facilitating the recruitment of HDAC1 to its promoter and enhancing histone H3K9 deacetylation. Consequently, BRMS1L-induced FZD10 silencing inhibits aberrant activation of WNT3-FZD10-M-oM-^AM-"-catenin signaling. Furthermore, BRMS1L is a target of miR-106b and miR-106b upregulation leads to BRMS1L reduction in breast cancer cells. RNAi-mediated silencing of BRMS1L expression promotes metastasis of breast cancer xenografts in immunocompromised mice, while ectopic BRMS1L expression inhibits metastasis. Therefore, BRMS1L provides an epigenetic regulation of Wnt signaling in breast cancer cells and acts as a breast cancer metastasis suppressor. Ther transfection analysis used here were further desxribed in Chang Gong, eta al.2013. miR-106b expression determines the proliferation paradox of TGF-M-NM-2 in breast cancer cells. Oncogene. 2013 A two chip study using total RNA recovered from MDA-MB-231 breast cancer cells transfected with negative control vector or vector overexpressing BRMS1L for 24 hours. Each chip measures the expression 45033 genes were collected from the authoritative data source including NCBI.
Project description:Obesity is thought to contribute to worse disease outcome in breast cancer as a result of increased levels of adipocyte-secreted endocrine factors, insulin, and insulin-like growth factors (IGFs) that accelerate tumor cell proliferation and impair treatment response. We examined the effects of patient obesity on primary breast tumor gene expression, by profiling transcription of a set of tumors for which the patients’ body mass index (BMI) was ascertained. Sample profiles were stratified according to patients’ obesity phenotype defined as normal (BMI <25), overweight (BMI 25-29.9), or obese (BMI>30). Widespread alterations in gene expression were evident in breast tumors from obese patients as compared to tumors from other patients, allowing us to define an obesity-associated cancer transcriptional signature of 662 genes. Keywords: two group comparison Primary breast tumor specimens were obtained from patients. Study volunteers completed questionnaires used to define historically normal (BMI<=24.9), overweight (BMI 25-29.9), or obese (BMI>=30) patient categories according to established WHO criteria.