Project description:Obesity is a known risk factor for breast cancer. To identify genes and underlying pathways in human breast cancer cells affected by interaction with mature adipocytes, two estrogen-receptor positive (ER+) breast cancer cell lines, MCF-7 and T47D, and the triple-negative (TN) breast cancer cell line MDA-MB-231 were cultivated in a co-culture system with or without differentiated murine 3T3-L1 adipocytes for the purpose of a microarray gene expression analysis. The use of in vitro differentiated 3T3-L1 adipocytes allowed comparable experimental conditions for each of the co-culture experiments with human breast cancer cell lines. For co-cultivation analyses of 3T3-L1 and breast cancer cells, we set up a two-dimensional transwell system, which enables intercellular communication through soluble factors secreted into the medium but inhibits intermixture of the different cell types. Following 5 days of co-culture with or without differentiated adipocytes, total RNA was isolated from the human breast cancer cells and subjected to microarray gene expression analyses.
Project description:In order to evaluate the impact of PCYOX1 deletion on adipogenesis, we applied a label-free mass spectrometry-based proteomic approach to compare the proteome of 3T3-L1 differentiated for 9 days to adipocytes after PCYOX1 gene silencing. Pcyox1 was silenced using shRNA lentiviral particles. Control cells were treated with shRNA lentiviral particles containing a negative construct.
Project description:Using RNA-Seq, we compared the transcriptomes of differentiated 3T3-L1 adipocytes for control and ZFP407-deficient cells Differentiated 3T3-L1 cells were electroporated with control or 1 of 2 Zfp407 siRNAs. Six independent siRNA electroporations were conducted for the control siRNA and 3 independent electroporations were conducted for each Zfp407 siRNA.
Project description:In the obese state, as adipose tissue expands, adipocytes become hypoxic and dysfunctional, leading to changes in the pattern of secreted proteins. To better understand the role of hypoxia in the mechanisms linked to obesity, we comparatively analyzed the secretome of differentiated 3T3-L1 adipocytes exposed to normoxia or hypoxia for 24 h. Proteins secreted into the culture media were precipitated using trichloroacetic acid and then digested by trypsin. Peptides were labeled by dimethyl labeling and analyzed by reversed phase nanoscale liquid chromatography coupled to a quadrupole Orbitrap mass spectrometer. Among factors downregulated in hypoxic conditions, we identified Decorin, a member of the leucine-rich proteoglycan family, Tissue Inhibitor of Metalloproteinase-2, Thrombospondin 1 and 2, all multifunctional proteins involved in extracellular matrix (ECM) homeostasis, and angiogenesis. Most findings were confirmed by expression studies of the relative genes in parallel experiments in vitro, in differentiated 3T3-L1 adipocytes, and in vivo, in fat tissues from obese vs. lean rats. Our observations are compatible with the concept that hypoxia may be an early trigger for ECM remodeling and angiogenesis in adipose tissue.
Project description:Differentiated 3T3-L1 adipocytes were either treated 0ng/ml or 500ng/ml rmIL-15 for 24 hours (n=3/group) qPCR gene expression profilling performed in vitro using recombinant murine (rm)IL-15 treated (500ng/ml) and untreated (control) 3T3-L1 cells. Equal amounts of total RNA per subject were used in the assay.
Project description:To identify the genes that are regulated by IRF7, we have performed DNA microarray in 3T3-L1 adipocytes differentiated from precursor cells infected with retrovirus empty or carrying IRF7. Plasmids (Empty- and IRF7-pMSCV) were kindly provided from Dr. Eguchi at the Okayama University Graduate School of Medicine, Okayama, Japan [Cell Metab. 2008;7: 86-94.]. Infected 3T3-L1 preadipocytes were selected by puromycin treatment and differentiated into adipocytes. 7 days after the induction of adipogenesis, total RNA was isolated.
