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1.  E2F transcription factor-1 regulates oxidative metabolism 
Nature cell biology  2011;13(9):10.1038/ncb2309.
Cells respond to stress by coordinating proliferative and metabolic pathways. Starvation restricts cell proliferative (glycolytic) and activates energy productive (oxidative) pathways. Conversely, cell growth and proliferation require increased glycolytic and decreased oxidative metabolism1. E2F transcription factors regulate both proliferative and metabolic genes2,3. E2Fs have been implicated in the G1/S cell cycle transition, DNA repair, apoptosis, development, and differentiation2-4. In pancreatic β-cells, E2F1 gene regulation facilitated glucose-stimulated insulin secretion5,6. Moreover, mice lacking E2F1 (E2f1−/−) were resistant to diet-induced obesity4. Here, we show that E2F1 coordinates cellular responses by acting as a regulatory switch between cell proliferation and metabolism. In basal conditions, E2F1 repressed key genes that regulate energy homeostasis and mitochondrial functions in muscle and brown adipose. Consequently, E2f1−/− mice had a marked oxidative phenotype An association between E2F1 and pRb was required for repression of genes implicated in oxidative metabolism. This repression was alleviated in a constitutive active CDK4 (CDK4R24C) mouse model or when adaptation to energy demand was required. Thus, E2F1 represents a metabolic switch from oxidative to glycolytic metabolism that responds to stressful conditions.
doi:10.1038/ncb2309
PMCID: PMC3849758  PMID: 21841792
4.  Adeno-Associated Virus–Mediated IL-10 Gene Transfer Suppresses Lacrimal Gland Immunopathology in a Rabbit Model of Autoimmune Dacryoadenitis 
This study is the first report of successful transduction of lacrimal gland cells with an adeno-associated virus vector and demonstration of a durable reduction of inflammatory lacrimal gland and ocular surface pathology.
Purpose.
To evaluate the effect of adeno-associated virus (AAV) vector–mediated viral (v)IL-10 gene expression on lacrimal gland (LG) immunopathology and ocular surface disease in a rabbit model of induced autoimmune dacryoadenitis (ID).
Methods.
Autologous peripheral blood lymphocytes, activated in a mixed-cell reaction when cocultured with purified rabbit lacrimal epithelial cells, induce a Sjögren's-like autoimmune dacryoadenitis when injected directly back into the donor animal's inferior LG. Four weeks after disease induction, AAV vector expressing the vIL-10 gene under control of a tetracycline-inducible promoter was injected into the inferior LG of the treatment group (ID/Rx), and doxycycline was fed orally to induce transgene expression. The ID group serving as control also received doxycycline. All LGs were removed 16 weeks after disease induction.
Results.
Clinical symptoms showed overall improvement in the ID/Rx group compared with the ID group. Histopathologic examination of the ID group's LG revealed scattered large lymphocytic foci and areas of altered or distorted acini, whereas the ID/Rx group had scattered small lymphocytic foci. The number of CD18+ cells was almost fivefold lower in the ID/Rx group than in the ID group. Although the total number of RTLA+ cells did not differ between the groups, the CD4/CD8 ratio was 16-fold smaller in the ID/Rx group.
Conclusions.
Animals with experimentally induced autoimmune dacryoadenitis appeared to benefit from AAV-mediated vIL-10 gene transfer therapy. Quantitative immunohistochemical analysis suggested that the therapy might not have been simply immunosuppressive but rather supported the induction of CD8+ regulatory cells.
doi:10.1167/iovs.10-5423
PMCID: PMC3066626  PMID: 20505195
5.  miR-143 Interferes with ERK5 Signaling, and Abrogates Prostate Cancer Progression in Mice 
PLoS ONE  2009;4(10):e7542.
Background
Micro RNAs are small, non-coding, single-stranded RNAs that negatively regulate gene expression at the post-transcriptional level. Since miR-143 was found to be down-regulated in prostate cancer cells, we wanted to analyze its expression in human prostate cancer, and test the ability of miR-43 to arrest prostate cancer cell growth in vitro and in vivo.
Results
Expression of miR-143 was analyzed in human prostate cancers by quantitative PCR, and by in situ hybridization. miR-143 was introduced in cancer cells in vivo by electroporation. Bioinformatics analysis and luciferase-based assays were used to determine miR-143 targets. We show in this study that miR-143 levels are inversely correlated with advanced stages of prostate cancer. Rescue of miR-143 expression in cancer cells results in the arrest of cell proliferation and the abrogation of tumor growth in mice. Furthermore, we show that the effects of miR-143 are mediated, at least in part by the inhibition of extracellular signal-regulated kinase-5 (ERK5) activity. We show here that ERK5 is a miR-143 target in prostate cancer.
Conclusions
miR-143 is as a new target for prostate cancer treatment.
doi:10.1371/journal.pone.0007542
PMCID: PMC2763222  PMID: 19855844
6.  Microenvironmental changes during differentiation of mesenchymal stem cells towards chondrocytes 
Chondrogenesis is a process involving stem-cell differentiation through the coordinated effects of growth/differentiation factors and extracellular matrix (ECM) components. Recently, mesenchymal stem cells (MSCs) were found within the cartilage, which constitutes a specific niche composed of ECM proteins with unique features. Therefore, we hypothesized that the induction of MSC differentiation towards chondrocytes might be induced and/or influenced by molecules from the microenvironment. Using microarray analysis, we previously identified genes that are regulated during MSC differentiation towards chondrocytes. In this study, we wanted to precisely assess the differential expression of genes associated with the microenvironment using a large-scale real-time PCR assay, according to the simultaneous detection of up to 384 mRNAs in one sample. Chondrogenesis of bone-marrow-derived human MSCs was induced by culture in micropellet for various periods of time. Total RNA was extracted and submitted to quantitative RT-PCR. We identified molecules already known to be involved in attachment and cell migration, including syndecans, glypicans, gelsolin, decorin, fibronectin, and type II, IX and XI collagens. Importantly, we detected the expression of molecules that were not previously associated with MSCs or chondrocytes, namely metalloproteases (MMP-7 and MMP-28), molecules of the connective tissue growth factor (CTGF); cef10/cyr61 and nov (CCN) family (CCN3 and CCN4), chemokines and their receptors chemokine CXC motif ligand (CXCL1), Fms-related tyrosine kinase 3 ligand (FlT3L), chemokine CC motif receptor (CCR3 and CCR4), molecules with A Disintegrin And Metalloproteinase domain (ADAM8, ADAM9, ADAM19, ADAM23, A Disintegrin And Metalloproteinase with thrombospondin type 1 motif ADAMTS-4 and ADAMTS-5), cadherins (4 and 13) and integrins (α4, α7 and β5). Our data suggest that crosstalk between ECM components of the microenvironment and MSCs within the cartilage is responsible for the differentiation of MSCs into chondrocytes.
doi:10.1186/ar2153
PMCID: PMC1906811  PMID: 17391539
7.  Transcriptional profiles discriminate bone marrow-derived and synovium-derived mesenchymal stem cells 
Arthritis Research & Therapy  2005;7(6):R1304-R1315.
Previous studies have reported that mesenchymal stem cells (MSC) may be isolated from the synovial membrane by the same protocol as that used for synovial fibroblast cultivation, suggesting that MSC correspond to a subset of the adherent cell population, as MSC from the stromal compartment of the bone marrow (BM). The aims of the present study were, first, to better characterize the MSC derived from the synovial membrane and, second, to compare systematically, in parallel, the MSC-containing cell populations isolated from BM and those derived from the synovium, using quantitative assays. Fluorescent-activated cell sorting analysis revealed that both populations were negative for CD14, CD34 and CD45 expression and that both displayed equal levels of CD44, CD73, CD90 and CD105, a phenotype currently known to be characteristic of BM-MSC. Comparable with BM-MSC, such MSC-like cells isolated from the synovial membrane were shown for the first time to suppress the T-cell response in a mixed lymphocyte reaction, and to express the enzyme indoleamine 2,3-dioxygenase activity to the same extent as BM-MSC, which is a possible mediator of this suppressive activity. Using quantitative RT-PCR these data show that MSC-like cells from the synovium and BM may be induced to chondrogenic differentiation and, to a lesser extent, to osteogenic differentiation, but the osteogenic capacities of the synovium-derived MSC were significantly reduced based on the expression of the markers tested (collagen type II and aggrecan or alkaline phosphatase and osteocalcin, respectively). Transcription profiles, determined with the Atlas Human Cytokine/Receptor Array, revealed discrimination between the MSC-like cells from the synovial membrane and the BM-MSC by 46 of 268 genes. In particular, activin A was shown to be one major upregulated factor, highly secreted by BM-MSC. Whether this reflects a different cellular phenotype, a different amount of MSC in the synovium-derived population compared with BM-MSC adherent cell populations or the impact of a different microenvironment remains to be determined. In conclusion, although the BM-derived and synovium-derived MSC shared similar phenotypic and functional properties, both their differentiation capacities and transcriptional profiles permit one to discriminate the cell populations according to their tissue origin.
doi:10.1186/ar1827
PMCID: PMC1297577  PMID: 16277684

Results 1-7 (7)