Project description:Dendritic cells (DC) arise from a diverse group of hematopoietic progenitors and have marked phenotypic and functional heterogeneity. We have found previously that activation of protein kinase C beta 2 (PRKCB2) by cytokines or phorbol esters drives normal human CD34(+) hematopoietic progenitors and myeloid leukemic blasts (KG1, K562 cell lines, and primary patient blasts) to differentiate into DC, but the genetic program triggered by PRKCB2 activation that results in DC differentiation is only beginning to be characterized. Of the cPKC isoforms, only PRKCB2 was consistently activated by DC differentiation-inducing stimuli in normal and leukemic progenitors. To examine early changes in gene expression following PRKCB2 activation, we employed the following cell lines: (1) the CD34(+) human acute myeloid leukemia derived cell line KG1, which undergoes DC differentiation following phorbol ester treatment; (2) KG1a, a spontaneously arising differentiation-resistant daughter cell line of KG1 that has lost PRKCB2 expression; (3) clones established from KG1a that stably express exogenous PRKCB2-GFP fusion proteins and are once again able to undergo DC differentiation (KG1a-PRKCB2-GFP Clone E9 and Clone E11). We examined changes in gene expression in these cells following treatment with the phorbol ester PMA (phorbol 12-myristate 13-acetate) for 2 hours. Since KG1 and KG1a differ in PRKCB2 expression but have similar expression of the other protein kinase C isoforms, this protocol will allow for the identification of genes regulated by PRKCB2 activation.
Project description:Dendritic cells (DC) arise from a diverse group of hematopoietic progenitors and have marked phenotypic and functional heterogeneity. We have found previously that activation of protein kinase C beta 2 (PRKCB2) by cytokines or phorbol esters drives normal human CD34(+) hematopoietic progenitors and myeloid leukemic blasts (KG1, K562 cell lines, and primary patient blasts) to differentiate into DC, but the genetic program triggered by PRKCB2 activation that results in DC differentiation is only beginning to be characterized. Of the cPKC isoforms, only PRKCB2 was consistently activated by DC differentiation-inducing stimuli in normal and leukemic progenitors. To examine early changes in gene expression following PRKCB2 activation, we employed the following cell lines: (1) the CD34(+) human acute myeloid leukemia derived cell line KG1, which undergoes DC differentiation following phorbol ester treatment; (2) KG1a, a spontaneously arising differentiation-resistant daughter cell line of KG1 that has lost PRKCB2 expression; (3) clones established from KG1a that stably express exogenous PRKCB2-GFP fusion proteins and are once again able to undergo DC differentiation (KG1a-PRKCB2-GFP Clone E9 and Clone E11). We examined changes in gene expression in these cells following treatment with the phorbol ester PMA (phorbol 12-myristate 13-acetate) for 2 hours. Since KG1 and KG1a differ in PRKCB2 expression but have similar expression of the other protein kinase C isoforms, this protocol will allow for the identification of genes regulated by PRKCB2 activation. KG1, KG1a, E9, and E11 were cultured for 2 hours in normal media +/- PMA (10 ng/ml). RNA was then isolated using RNeasy mini-columns (Qiagen) following the standard protocol. Samples were then sent to Expression Analysis, who carried out quality control, sample processing/labeling, hybridization to Affymetrix GeneChip arrays (Human U133 2.0 Plus), imaging, and analysis according to their standard protocols. Gene expression profiles were generated for each cell line in the presence and absence of phorbol ester stimulation, for a total of 12 samples (E9 +/- PMA and E11 +/- PMA were run in duplicate).
Project description:Mitogen-activated protein kinases (MAPKs) are key mediators of the T cell receptor (TCR) signals but their roles in T helper (Th) cell differentiation are unclear. Here we showed that the MAPK kinase kinases MEKK2 (encoded by Map3k2) and MEKK3 (encoded by Map3k3),negatively regulated transforming growth factor-beta (TGF-beta)-mediated Th cell differentiation.Map3k2-/-Map3k3Lck-Cre/- mice showed an abnormal accumulation of regulatory T (Treg) and Th17 cells in the periphery, consistent with Map3k2-/-Map3k3Lck-Cre/- naïve CD4+ T cells’ differentiation into Treg and Th17 cells with a higher frequency than wild-type (WT) cells after TGF-beta stimulation in vitro. In addition, Map3k2-/-Map3k3Lck-Cre/- mice developed more severe experimental autoimmune encephalomyelitis. Map3k2-/-Map3k3Lck-Cre/- T cells exhibited impaired phosphorylation of the SMAD2 and SMAD3 proteins at their linker regions, which negatively regulated the TGF-beta responses in T cells. Thus, the crosstalk between TCR-induced MAPK and the TGF-beta signaling pathways is important in regulating Th cell differentiation. CD4+CD62L-CD44+ cells were FACS sorted from C57BL/6 Lck-Cre MEKK2 KO MEKK3F/-(dKO) or C57BL/6 WT mice
Project description:This research trial is testing a combination of two experimental drugs, MSC1936369B (Mitogen-activated protein extracellular signal-regulated kinase (MEK) Inhibitor) and SAR245409 (Phosphatidylinositol 3-kinase (Pi3K)/Mammalian Target of Rapamycin (mTOR) inhibitor), in the treatment of locally advanced or metastatic solid tumors. The primary purpose of the study is to determine the maximum tolerated dose of the drug combination.
Project description:Mitogen-activated protein kinases (MAPKs) are key mediators of the T cell receptor (TCR) signals but their roles in T helper (Th) cell differentiation are unclear. Here we showed that the MAPK kinase kinases MEKK2 (encoded by Map3k2) and MEKK3 (encoded by Map3k3),negatively regulated transforming growth factor-beta (TGF-beta)-mediated Th cell differentiation.Map3k2-/-Map3k3Lck-Cre/- mice showed an abnormal accumulation of regulatory T (Treg) and Th17 cells in the periphery, consistent with Map3k2-/-Map3k3Lck-Cre/- naïve CD4+ T cells' differentiation into Treg and Th17 cells with a higher frequency than wild-type (WT) cells after TGF-beta stimulation in vitro. In addition, Map3k2-/-Map3k3Lck-Cre/- mice developed more severe experimental autoimmune encephalomyelitis. Map3k2-/-Map3k3Lck-Cre/- T cells exhibited impaired phosphorylation of the SMAD2 and SMAD3 proteins at their linker regions, which negatively regulated the TGF-beta responses in T cells. Thus, the crosstalk between TCR-induced MAPK and the TGF-beta signaling pathways is important in regulating Th cell differentiation.
Project description:Metabolic remodeling is one of the earliest events that occur during the early differentiation of embryonic stem cells (ESCs), but how these metabolic changes are regulated and participate in the cell differentiation is still largely undissected. Here, we define the fatty acid metabolism as a key player in definitive endoderm (DE) differentiation from human ESCs. During DE differentiation, lipogenesis is decreased while fatty acid β oxidation is enhanced. This dynamic is due to the phosphorylation of lipogenic enzyme acetyl-CoA carboxylase (ACC), which is mediated by AMP-activated protein kinase (AMPK) and inhibits the de novo fatty acid synthesis. More importantly, inhibition of fatty acid synthesis by either its inhibitors or AMPK agonist, significantly promotes the human endoderm differentiation, while blockade of the fatty acid oxidation by genetic manipulation or chemical antagonists impairs the differentiation. The de novo fatty acid synthesis inhibition and fatty acid β oxidation maintaining contribute to the accumulation of cellular acetyl-CoA, which is the essential substrate for protein acetylation. Further study reveals that SMAD3 acetylation and the subsequent subcellular localization exhibit significant change upon interfering fatty acid metabolism. Mechanistically, the accumulation of cellular acetyl-CoA guarantees the acetylation of key transcription factor SMAD3, which further causes the nuclear localization and activation of SMAD signaling pathway to promote DE differentiation. Thus, our current study reveals a fatty acid synthesis/oxidation shift during early differentiation and presents an instructive role of fatty acid metabolism in regulating human early endoderm differentiation.
Project description:Metabolic remodeling is one of the earliest events that occur during the early differentiation of embryonic stem cells (ESCs), but how these metabolic changes are regulated and participate in the cell differentiation is still largely undissected. Here, we define the fatty acid metabolism as a key player in definitive endoderm (DE) differentiation from human ESCs. During DE differentiation, lipogenesis is decreased while fatty acid β oxidation is enhanced. This dynamic is due to the phosphorylation of lipogenic enzyme acetyl-CoA carboxylase (ACC), which is mediated by AMP-activated protein kinase (AMPK) and inhibits the de novo fatty acid synthesis. More importantly, inhibition of fatty acid synthesis by either its inhibitors or AMPK agonist, significantly promotes the human endoderm differentiation, while blockade of the fatty acid oxidation by genetic manipulation or chemical antagonists impairs the differentiation. The de novo fatty acid synthesis inhibition and fatty acid β oxidation maintaining contribute to the accumulation of cellular acetyl-CoA, which is the essential substrate for protein acetylation. Further study reveals that SMAD3 acetylation and the subsequent subcellular localization exhibit significant change upon interfering fatty acid metabolism. Mechanistically, the accumulation of cellular acetyl-CoA guarantees the acetylation of key transcription factor SMAD3, which further causes the nuclear localization and activation of SMAD signaling pathway to promote DE differentiation. Thus, our current study reveals a fatty acid synthesis/oxidation shift during early differentiation and presents an instructive role of fatty acid metabolism in regulating human early endoderm differentiation.
Project description:Myofibroblast is a specific type of mesenchymal cell characterized by synthesis of extracellular matrix and contractile activity. While it serves a beneficial function during tissue wound healing under physiological conditions, it can cause devastating damage to organs afflicted with fibrosis. Myofibroblasts are also present in tumor stroma and contribute actively to tumor growth and spreading. Chicken embryo dermal myofibroblasts (CEDM) represent a novel ex vivo model suitable for the analysis of myofibroblastic phenotype as they show strongly pronounced, uniform and self-sustained myofibroblastic phenotype that is stable in time. As myofibroblastic differentiation is controlled chiefly by TGF-beta signaling, the understanding of the differentiation program entails the determination of TGF-beta-regulated genes. To achieve such a goal, we performed oligonucleotide microarray analysis of CEDM cells treated with a selective TGFBR1 kinase inhibitor. Genes reported previously to be under the control of TGF-beta signaling in mammalian cells appeared among the affected genes also in CEDM cells and many so far unknown TGF-beta targets were revealed. Comparison of the expression profiles of chicken embryo dermal myofibroblasts in culture treated with TGFBR1 Kinase Inhibitor II or DMSO only. Three biological replicates were analyzed for each group.