Id1 mRNA Research Articles

Inhibitor of DNA Binding Protein 3 (ID3) and Nuclear Respiratory Factor 1 (NRF1) Mediated Transcriptional Gene Signatures are Associated with the Severity of Cerebral Amyloid Angiopathy.

Cerebral amyloid angiopathy (CAA) is a degenerative vasculopathy. We have previously shown that transcription regulating proteins- inhibitor of DNA binding protein 3 (ID3) and the nuclear respiratory factor 1 (NRF1) contribute to vascular dysregulation. In this study, we have identified sex specific ID3 and NRF1-mediated gene networks in CAA patients diagnosed with Alzheimer's Disease (AD). High expression of ID3 mRNA coupled with low NRF1 mRNA levels was observed in the temporal cortex of men and women CAA patients. Low NRF1 mRNA expression in the temporal cortex was found in men with severe CAA. High ID3 expression was found in women with the genetic risk factor APOE4. Low NRF1 expression was also associated with APOE4 in women with CAA. Genome wide transcriptional activity of both ID3 and NRF1 paralleled their mRNA expression levels. Sex specific differences in transcriptional gene signatures of both ID3 and NRF1 were observed. These findings were further corroborated by Bayesian machine learning and the GeNIe simulation models. Dynamic machine learning using a Monte Carlo Markov Chain (MCMC) gene ordering approach revealed that ID3 was associated with disease severity in women. NRF1 was associated with CAA and severity of this disease in men. These findings suggest that aberrant ID3 and NRF1 activity presumably plays a major role in the pathogenesis and severity of CAA. Further analyses of ID3- and NRF1-regulated molecular drivers of CAA may provide new targets for personalized medicine and/or prevention strategies against CAA.

RGMb impacts partial epithelial-mesenchymal transition and BMP2-Induced ID mRNA expression independent of PD-L2 in nonsmall cell lung cancer cells.

PD-1/PD-ligand-axis immunotherapy-mediated activation of T-cells for cancer cell elimination is a promising treatment of nonsmall cell lung cancer (NSCLC). However, the effect of immunotherapy on intracellular signaling pathways in cancer cells still needs further delineation. Repulsive Guidance Molecule b (RGMb), a regulator of Bone Morphogenetic Proteins (BMPs) signaling, interacts with the PD-ligand, PD-L2, at cancer cell membranes. Accordingly, a clarification of the functions of RGMb and its relation to PD-L2 might provide insight into NSCLC cell signaling responses to PD-1/PD-ligand-axis immunotherapy. In this study, the functions of RGMb and PD-L2 were examined using the two NSCLC cell lines HCC827 and A549. CRISPR/Cas9 was used to decrease the expression of RGMb and PD-L2, while lentiviral vectors were used to increase their expression. Downstream effects were examined by RT-qPCR and immunoassays. Ectopic expression of RGMb impacted BMP2-induced expression of ID1 and ID2 messenger RNA (mRNA) independently of PD-L2, while RGMb depletion by CRISPR/Cas9 did not affect the BMP2-mediated induction of ID1, ID2, and ID3 mRNA. However, depletion of RGMb resulted in a partial epithelial-mesenchymal transition (EMT) gene expression profile in HCC827 cells, which was not mimicked by PD-L2 depletion. The results show that RGMb is a coregulator of BMP signaling and hence, ID mRNA expression and that RGMb can control the EMT balance in NSCLC cells. However, RGMb appears to exert these functions independently of PD-L2, and accordingly, the PD-1/PD-ligand axis for immune surveillance in NSCLC cells.

Effect of trametinib and anti-PD-1 combo on tumor growth and survival of KRAS-mutant lung cancer by ID1 downregulation.

e14633 Background: Although anti-PD-1/PD-L1 antibodies represent a major breakthrough in NSCLC patients’ survival, this treatment efficacy is highly dependent on tumor PD-L1 expression. We reported the role of ID1 and the efficacy of a combined blockade of PD-1-ID1 in a KRAS mutant NSCLC mouse model (Baraibar et al; Cancers 2020). Trametinib, which is an oral MEK1/2 inhibitor, acts downstream of KRAS. Here we evaluate trametinib as an ID1 inhibitor able to enhance immunotherapy efficacy through PD-L1 overexpression. Methods: To explore whether MEK1/2 inhibition reduces ID1 expression in vitro and in vivo, experiments in NSCLC cells (human and murine) and in murine models were performed. RNAseq analysis was conducted to elucidate the pathways implicated in ID1 inhibition. Trametinib resistant (TR) cells were generated to analyze the effect of ID1 in the acquired resistance to treatment. Apoptosis was measured by flow cytometry. PD-L1 expression was evaluated by flow cytometry in control, ID1 silenced, ID1-overexpressing and TR cell lines. Treatment of trametinib combined with anti-PD1 was performed in KRAS-mutant LUAD models. Results: In vitro experiments in NSCLC cells showed ID1 inhibition at protein level after MEK1/2 blockade. However, we observe an increase in ID1 mRNA levels following treatment. In vivo experiments performed in C57BL6J and in ID1-deficient mice showed no significant differences in tumor growth between ID1 knock-out and ID1 wild-type mice treated with trametinib. IHC analysis of those tumor samples showed reduced ID1 levels (LLC p<0.001; CMT-167 p<0.0001). RNAseq analysis revealed an enrichment of ubiquitin-proteasome pathway after trametinib exposure. Blockade of proteasome activity with a specific inhibitor, restored ID1 levels. TR cells did not show MEKi induced ID1 inhibition, moreover, ID1 blockade rescued the sensitivity to trametinib in human and murine NSCLC TR cells (p<0.001). Flow cytometry analysis showed increased PD-L1 expression (p<0.001) in human and murine NSCLC cell lines after trametinib administration. In contrast, ID1-overexpressing cells and TR cells did not show PD-L1 upregulation after MEK inhibition. In vivo experiments confirmed the therapeutic efficacy of trametinib and anti-PD-1 combo, reducing tumor growth (p<0.05) and increasing mice survival (p<0.05), compared with trametinib monotherapy or immunotherapy alone. Conclusions: Pharmacological inhibition of MEK1/2 decreased ID1 expression in vitro and in vivo, replicating the effect of a specific shRNA against ID1, through proteasome activation. PD-L1 upregulation induced by ID1 blockade after trametinib treatment sensitized KRAS-mutant NSCLC cells to PD-1/PD-L1 immunotherapy, blocking tumor growth and improving overall survival.

METTL3 promotes pancreatic cancer proliferation and stemness by increasing stability of ID2 mRNA in a m6A-dependent manner

In eukaryotes, N6-methyladenosine (m6A) is the most prevalent epigenetic alteration. Methyltransferase-like 3 (METTL3) is a key player in the control of m6A, although its function in pancreatic cancer is incompletely understood. In this study, we examined the role that METTL3 plays in pancreatic cancer cell proliferation and stemness. We discovered that in pancreatic cancer cells, METTL3-mediated m6A alterations regulate ID2 as a downstream target. The stability of ID2 mRNA was decreased and m6A modification was effectively eliminated by METTL3 knockdown in pancreatic cancer cells. We also demonstrate that m6a-YTHDF2 is necessary for the METTL3-mediated stabilization of ID2 mRNA. Additionally, we show that ID2 controls the stemness molecules NANOG and SOX2 via the PI3K-AKT pathway to support pancreatic cancer growth and stemness maintenance. Our data suggest that METTL3 may post-transcriptionally upregulate ID2 expression in an m6A-YTHDF2-dependent manner to further promote the stabilization of ID2 mRNA, which may be a new target for pancreatic cancer treatment.

Comparing the development of cortex-wide gene expression patterns between two species in a common reference frame

Advances in sequencing techniques have made comparative studies of gene expression a current focus for understanding evolutionary and developmental processes. However, insights into the spatial expression of genes have been limited by a lack of robust methodology. To overcome this obstacle, we developed methods and software tools for quantifying and comparing tissue-wide spatial patterns of gene expression within and between species. Here, we compare cortex-wide expression of RZRβ and Id2 mRNA across early postnatal development in mice and voles. We show that patterns of RZRβ expression in neocortical layer 4 are highly conserved between species but develop rapidly in voles and much more gradually in mice, who show a marked expansion in the relative size of the putative primary visual area across the first postnatal week. Patterns of Id2 expression, by contrast, emerge in a dynamic and layer-specific sequence that is consistent between the two species. We suggest that these differences in the development of neocortical patterning reflect the independent evolution of brains, bodies, and sensory systems in the 35 million years since their last common ancestor.

ID2 inhibits lung adenocarcinoma cell malignant behaviors by inhibiting the activation of the PI3K/AKT/mTOR signaling pathway

Lung cancer is the most common cancer and one of the main causes of cancer-related deaths, presenting in most cases as metastatic disease. Given the frequent gene mutation and/or signaling deregulation in lung adenocarcinoma, identifying novel factors or agents that target these signaling pathways may be promising strategies for lung adenocarcinoma therapy. Herein, we identified inhibitor of DNA binding 2 (ID2) as an aberrantly downregulated gene in lung adenocarcinoma. ID2 overexpression not only suppressed the viability, colony formation ability, and migration ability of lung adenocarcinoma cells but also decreased the protein levels of N-cadherin, MMP2, MMP9 and the phosphorylation levels of AKT and mTOR. The effects of PI3K/AKT/mTOR signaling agonist on lung adenocarcinoma cells were opposite to those of ID2 overexpression, partially reversing the effects of ID2 overexpression. In these experimental tissue samples, ID2 protein levels and mRNA expression were also down-regulated compared with those in adjacent non-cancerous tissues. Altogether, these findings indicated that ID2 exerts its tumor-suppressive effects on the malignant behavior of lung adenocarcinoma cells by inhibiting the activation of the PI3K/AKT/mTOR signaling pathway. Restoration of ID2 expression in lung adenocarcinoma cells may improve the therapeutic efficacy of lung adenocarcinoma therapies.

Dietary supplementation with selenomethionine enhances antioxidant capacity and selenoprotein gene expression in layer breeder roosters

This study's objective was to investigate the effects of dietary Se (in the form of selenomethionine) on the antioxidant activity and selenoprotein gene expressions in layer breeder roosters. One hundred and eighty, 36-wk-old Jingfen layer breeder roosters were randomly allocated to one of 5 dietary treatments (0, 0.25, 0.5, 1, or 2 mg/kg Se) for 6 wk on a corn-soybean meal-based diet. Antioxidant parameters and selenoprotein gene expressions were assessed at the end of the experiment. The results showed that Se supplementation significantly increased the activity of T-SOD, CAT, GSH-Px, and superoxide anion scavenging ability in plasma (P ≤ 0.05), and activities of T-SOD, CAT, GSH-Px, superoxide anion scavenging ability, and hydroxyl radical scavenging ability in the liver, kidney, and testis (P < 0.05). Moreover, MDA levels were significantly reduced in plasma, liver, kidney, and testis (P < 0.01), compared to the control group. Furthermore, the dietary administration of Se significantly increased TrxR2 and GPx4 mRNA levels in kidney and testis, and ID1 mRNA levels in liver and kidney. Most of the antioxidant parameters and selenoprotein-related gene expressions significantly increased, and MDA significantly decreased at dietary supplementation with 0.5 mg/kg Se. Whereas a higher dose of Se level (1 or 2 mg/kg) inhibited the activities of some of the antioxidant enzymes and selenoprotein-related gene expressions in selected tissues. In conclusion, dietary Se supplementation with 0.5 mg/kg significantly improved roosters’ antioxidant status and selenoprotein-related gene expression in liver, kidney, and testis, while higher doses led to inhibit these; dietary Se might increase reproductive performance by enhancing their antioxidant status in roosters.

Regulation and function of Id2 in plasmacytoid dendritic cells

Plasmacytoid dendritic cells (pDCs) are specialized type I interferon (IFN-I) producing cells that promote anti-viral immune responses and contribute to autoimmunity. Development of pDCs requires the transcriptional regulator E2–2 and is opposed by inhibitor of DNA binding 2 (Id2). Prior work indicates Id2 is induced in pDCs upon maturation and may affect pDC IFN-I production via suppression of E2–2, suggesting an important yet uncharacterized role in this lineage. We found TLR7 agonists stimulate Id2 mRNA and protein expression in pDCs. We further show that transcriptional activation of Id2 is dependent on the E2 ubiquitin-conjugating enzyme Ubc13, but independent of IFN-I signaling in response to TLR7 agonist stimulation. Nonetheless, conditional Id2 depletion in pDCs indicates Id2 is dispensable for TLR7 agonist-induced maturation and inhibition of E2–2 expression. Thus, we identify new mechanisms of Id2 regulation by Ubc13, which may be relevant for understanding Id2 gene regulation in other contexts, while ruling out major roles for Id2 in pDC responses to TLR7 agonists.

Circadian Period 2 (Per2) downregulate inhibitor of differentiation 3 (Id3) expression via PTEN/AKT/Smad5 axis to inhibits glioma cell proliferation

ABSTRACT In this study, we employed multiple laboratory techniques to acknowledge the biological activities and processes of Per2 and Id3 in glioma. We analyzed TCGA and CGGA databases for seeking association among Per2, Id3, and clinical features in glioma. Immunohistochemistry and Western blot were used to detect protein expression levels. CCK-8 assay, colony formation assay, Transwell assay, the wound healing assay, flow cytometric, and Xenograft nude mice were used to acknowledge the impact of Per2 and Id3 on biological behavior of glioma. The results showed that the Per2 mRNA expression was negatively correlated with the WHO grade, while the Id3 mRNA expression was positively correlated with the WHO grade in patients with glioma in TCGA and CGGA databases. Per2 and Id3 maintained separate prognostic abilities and had a negative connection in human glioma. In the clinical sample study, Per2 and Id3 were validated at the protein level with the same results compared to the mRNA expression level in TCGA and CGGA. By using a wide range of functional examples, overexpression of Per2 restrains malignant biological behaviors in glioma cells by many ways, while Id3 promotes malignant biological behaviors in glioma cells. Furthermore, overexpression of Per2 can inhibit Id3 expression via regulating PTEN/AKT/Smad5 signaling pathway and thereby abolish malignant biological behaviors that are caused by Id3 overexpression. These results suggested that Per2 inhibits glioma cell proliferation through regulating PTEN/AKT/Smad5/Id3 signaling pathway, which may be a viable therapeutic target for glioma.

Discovery of the inhibitor of DNA binding 1 as a novel marker for radioresistance in pancreatic cancer using genome-wide RNA-seq.

Purpose/Objective(s): Discovery of genetic drivers of radioresistance is critical for developing novel therapeutic strategies to combine with radiotherapy of radioresistant PDAC. In this study, we used genome-wide RNA-seq to identify genes upregulated in generated radioresistant PDAC cell lines and discovered the Inhibitor of DNA Binding 1 (ID1) gene as a potential regulator of radioresistance in PDAC. Materials/Methods: Radioresistant clones of the PDAC cell lines MIA PaCa-2 and PANC-1 were generated by delivering daily ionizing irradiation (IR) (2 Gy/day) in vitro over two weeks (total 20 Gy) followed by standard clonogenic assays following one week from the end of IR. The generated RR and parental cell lines were submitted for RNA-seq analysis to identify differentially expressed genes. The Limma R package was used to calculate differential expression among genes. Log2 fold change values were calculated for each sample compared to the control. Genes with an absolute fold change > 1 were considered significant. RNA sequencing expression data from the Cancer Genome Atlas (TCGA) database was analyzed through the online databases GEPIA, cBioPortal, and the Human Protein Atlas. Results: Following exposure to two weeks of 2 Gy daily IR in vitro, the two PDAC cell lines showed significantly greater clonogenic cell survival than their parental cell lines, indicating enhanced RR in these cells. RNA-seq analysis comparing parental and RR cell lines found upregulated seven genes (TNS4, ZDHHC8P1, APLNR, AQP3, SPP1, ID1, ID2) and seven genes downregulated (PTX3, ITGB2, EPS8L1, ALDH1L2, KCNT2, ARHGAP9, IFI16) in both RR cell lines. Western blotting confirmed increased expression of the ID1 protein in the RR cell lines compared to their parental cell lines. We found that ID1 mRNA was significantly higher in PDAC tumors compared to matched normal and high ID1 expression correlated with significantly worse disease-free survival (DFS) in PDAC patients (HR = 2.2, log rank P = 0.009). ID1 mRNA expression was also strongly correlated in tumors with TP53 mutation, a known driver of radioresistance. Conclusion: Our analysis indicates a novel role of ID1 in PDAC radioresistance. ID1 expression is higher in tumor tissue compared to normal, and high expression correlates with both worse DFS and association with the TP53 mutation, suggesting that targeting ID1 prior to IR is an attractive strategy for overcoming radioresistance in PDAC.

METTL3 Regulates m6A Modification of ID2 mRNA to Promote Pancreatic Cancer Development

METTL3 Regulates m6A Modification of ID2 mRNA to Promote Pancreatic Cancer Development

Involvement of NR5A1 and NR5A2 in the Regulation of Steroidogenesis by Clock Gene and BMPs by Human Granulosa Cells

We previously reported that the expression levels of Clock gene are linked to the expression levels of steroidogenetic enzymes in human granulosa cells (EJ 2019). However, the downstream molecules of the Clock gene actions in the regulation of ovarian steroidogenesis have yet to be elucidated. In the present study, we investigated the roles of the transcription factors, NR5A1 (also known as SF-1) and NR5A2 (LRH-1), which play key roles in the reproductive function as well as steroidogenesis by focusing on the functional link between Clock gene and bone morphogenetic protein (BMP) signaling using human granulosa KGN cells. First of all, we examined the effects of BMPs/growth differentiation factor (GDF) on forskolin (FSK)-induced steroidogenesis. As a result, FSK-induced mRNA levels of StAR and P450scc, but not P450arom, were potently suppressed by treatments with BMP-6, -9, -15 and GDF-9. The expression levels of NR5A1 and NR5A2 mRNA were also upregulated by FSK treatment, while the BMP-target gene Id-1 mRNA levels were stimulated by the treatment with BMPs. Of interest, treatments with BMPs/GDF increased FSK-induced NR5A1 mRNA levels but suppressed FSK-induced NR5A2 mRNA levels by granulosa cells. The expression levels of NR5A1 mRNA were positively correlated with the changes of P450arom and 3βHSD mRNA, whereas the expression levels of NR5A2 mRNA were correlated with that of StAR and P450scc mRNA. In addition, the expression levels of NR5A1 and NR5A2 mRNAs were positively correlated with the levels of Clock mRNA. In particular, Clock mRNA levels showed highly positive correlation with the levels of NR5A2 mRNA compared with NR5A1 mRNA. Of note, Id-1 mRNA levels were positively correlated with the levels of NR5A1 mRNA, but negatively correlated with that of NR5A2 mRNA. Furthermore, the inhibition of Clock gene expression by siRNA attenuated the expression levels of NR5A1 and NR5A2 mRNA, resulting in decreased mRNA levels of StAR and P450arom in the presence of FSK. Thus, the present results suggested a novel mechanism by which Clock expression is functionally linked to the expression of NR5A1 and NR5A2, the latter of which is further regulated by BMP signaling by granulosa cells. The interaction among Clock, NR5A1/NR5A2 and BMPs may be involved in the fine tuning of steroidogenesis by ovarian follicles.

Orexin A Enhances Pro-Opiomelanocortin Transcription Regulated by BMP-4 in Mouse Corticotrope AtT20 Cells.

Orexin is expressed mainly in the hypothalamus and is known to activate the hypothalamic–pituitary–adrenal (HPA) axis that is involved in various stress responses and its resilience. However, the effects of orexin on the endocrine function of pituitary corticotrope cells remain unclear. In this study, we investigated the roles of orexin A in pro-opiomelanocortin (POMC) transcription using mouse corticotrope AtT20 cells, focusing on the bone morphogenetic protein (BMP) system expressed in the pituitary. Regarding the receptors for orexin, type 2 (OXR2) rather than type 1 (OX1R) receptor mRNA was predominantly expressed in AtT20 cells. It was found that orexin A treatment enhanced POMC expression, induced by corticotropin-releasing hormone (CRH) stimulation through upregulation of CRH receptor type-1 (CRHR1). Orexin A had no direct effect on the POMC transcription suppressed by BMP-4 treatment, whereas it suppressed Smad1/5/9 phosphorylation and Id-1 mRNA expression induced by BMP-4. It was further revealed that orexin A had no significant effect on the expression levels of type I and II BMP receptors but upregulated inhibitory Smad6/7 mRNA and protein levels in AtT20 cells. The results demonstrated that orexin A upregulated CRHR signaling and downregulated BMP-Smad signaling, leading to an enhancement of POMC transcription by corticotrope cells.

BONE MORPHOGENETIC PROTEIN 2 PROMOTES HUMAN TROPHOBLAST CELL INVASION AND ENDOTHELIAL-LIKE TUBE FORMATION THROUGH ID1-MEDIATED UP-REGULATION OF IGF BINDING PROTEIN-3

Objective: Extravillous cytotrophoblasts (EVTs) invade into the uterine wall and remodel spiral arteries for proper placentation. Insufficient EVTs invasion and poor spiral arterial remodeling are associated with preeclampsia occurrence. Studies from us and others have demonstrated that the transforming growth factor-beta superfamily member bone morphogenetic protein 2 (BMP2) plays important roles in endometrial decidualization and trophoblast cell invasion. However, BMP2 has also been shown to regulate endothelial cell migration and capillary-like tube formation, as has its downstream signaling molecule inhibitor of DNA binding 1 (ID1). Interestingly, insulin-like growth factor binding protein 3 (IGFBP3) also promotes endothelial precursor cell migration and angiogenesis. Moreover, Id1 shows regulatory effect on Igfbp3 expression in rat prostate epithelial cells. However, whether ID1 and IGFBP3 are integrated in BMP2 signaling and involved in the regulation of trophoblast invasive and endovascular differentiation remains unknown. The objective of our study was to examine the effects of BMP2 on ID1 and IGFBP3 expression and their roles in BMP2-regulated human trophoblast invasion and endothelial-like tube formation. Design and method: Primary and immortalized (HTR8/SVneo) cultures of human trophoblast cells were employed as study models. RT-PCR and Western blot assay were used to study mRNA and protein levels. Small interfering RNA (siRNA) was used to check the roles of key molecules. Matrigel-coated transwell assay and endothelial-like tube formation assay were used to examine cell invasiveness and angiogenesis respectively. Results: BMP2 treatment increased ID1 and IGFBP3 mRNA and protein levels in HTR8/SVneo and primary human EVT cells. Intriguingly, ID1 was essential for BMP2-induced IGFBP3 up-regulation in both study models, and BMP2-induced trophoblast invasion was attenuated by knockdown of either ID1 or IGFBP3. In addition, BMP2 significantly increased endothelial-like tube formation and knockdown of ID1 and IGFBP3 reduced basal and BMP2-induced tube formation in HTR8/SVneo cells. Similarly, BMP2 increased placenta growth factor (PlGF) production in HTR8/SVneo cells and these effects were attenuated by knockdown of ID1 or IGFBP3. Conclusions: Our results reveal that BMP2 promotes trophoblast cell invasion and endothelial-like tube formation by ID1-mediated IGFBP3 up-regulation.

Abstract 15013: Ischemic Mitral Regurgitation is Associated With Impaired Transforming Growth Factor/Bone Morphogenic Protein Signaling and Increased CD45+ Cell Presence in the Mitral Valve Interstitial Cell Population

Introduction: Ischemic mitral regurgitation (IMR) develops in a fraction of patients in response to left ventricular (LV) remodeling after ischemia. IMR independently predicts adverse events and doubles mortality. While largely driven by LV distortion, the susceptibility of the mitral valve (MV) to undergo remodeling may play a role in determining whether MR develops. We hypothesized that impaired cellular response in MV cells may contribute to MR development by inducing maladaptive tissue remodeling. Methods: Dorsett hybrid sheep (n=32) were subjected to ligation of the circumflex coronary artery to induce myocardial infarction (MI). Development of MR was reported by echocardiography. MV leaflets and isolated MV interstitial cells (MVIC) were collected at baseline (Control), 4-, and 8-weeks post MI. RNAseq (150 paired end reads, 20 million reads/sample) was performed on MV leaflets from all groups. MVICs were treated with for 24h with 10ng/ml TGFβ1 of 50ng/ml BMP4. Results: Gene set enrichment analysis using pre-defined gene sets from the Gene Ontology project, considering genes with significant changes (p&lt;0.05) between MV with/without MR showed enrichment of cardiac contraction biological processes. TGFβ/BMP-dependent SMAD7 was the main hub in the protein-protein-interaction network of the top contributing genes to the enriched pathways in MR. In vitro, collagen matrix-contracting ability of MR MVICs was higher than non-MR MI MVICs. MVICs from MI sheep were less responsive to BMP4 pro-osteogenic stimulation (as reflected by blunted increased in ID2, osteopontin and osteocalcin mRNA) than control. MVICs from sheep with MR had a diminished COL1A1 mRNA response to TGFβ1 and enhanced pro-chondrogenic RUNX2 and SOX9 mRNA response to BMP4 vs. non-MR MVICs. Baseline CD45 expression was detectable only in MR MVICs. Upon TGFβ1 stimulation, CD45 expression was detected in all groups. Immunostaining confirmed increased presence of CD45+ cells in IMR MV interstitium. Conclusions: MVs from sheep developing MR had altered TGFβ/BMP response, which may be partially mediated by increased CD45+ fibrocyte presence. Pharmacological strategies aimed to modulate TGFβ/BMP signaling after MI may protect from pathological MV remodeling leading to IMR.

A FUNCTIONAL TL1A/DR3 SYSTEM IS CRUCIAL FOR OPTIMAL GENERATION OF PATHOGENIC TH9 CELLS IN MURINE CROHN’S DISEASE-LIKE ILEITIS

Abstract New evidence suggests the implication of IL-9-secreting TH9 cells in the pathogenesis of Crohn’s disease (CD). The role of death receptor 3 (DR3) in the differentiation and function of TH9 cells in CD is not fully explored. Thus, here, we investigated the role of a functional DR3 receptor in disease progression and activation of downstream signaling pathways relevant to TH9 cells. We found that lack of DR3 ameliorated ileitis in SAMP/YitFc (SAMP,WT) mice, reduced by 40% Baft3, PU.1, il-9 mRNAs and IL-9 protein, increased by 3-fold Id3 mRNA in ileal tissues (P≤0.003). TH9 cells from DR3−/−×SAMP (KO) mice harbored 2-fold less il-9 mRNA and IL-9 and TNF proteins (P≤0.0002), 5-fold higher IL-10 protein than WT TH9 cells (P&amp;lt;0.0001). RNA-seq analysis of WT and KO TH9 cells is currently being analyzed. Rag2−/− recipients of KO TH9 cells developed less severe colitis (P=0.005). Histology score of ilea and colons from SAMP×Rag2−/− is currently being evaluated. The frequency of KO TH9 cells producing IL-9 in Rag2−/− MLNs was 2-fold lower than that of mice reconstituted with WT TH9 cells (P=0.02). The frequency of IL-9-producing KO TH9 cells in SAMP×Rag2−/− SPLs and MLNs was 2-fold lower than that of mice reconstituted with WT TH9 cells (P≤0.006). In conclusion, DR3 receptor heavily contributes to IL-9-signaling pathway activation and it is required for the secretion of higher amount of IL-9 protein by TH9 cells in SAMP mice. KO TH9 cells were less colitogenic that those isolated from WT mice, indicating a crucial role of a functional DR3 receptor in TH9 pathogenicity. Collectively, our results hold great translational significance by showing that modulation of DR3 signaling may be a novel therapeutic target for the treatment of CD.

Transcription factor ID1 is involved in decidualization of stromal cells: Implications in preeclampsia.

Decidual stromal cells (DSC) from women with preeclampsia (PE) show defective decidualization upon in vitro treatment with cAMP. Decidualization is associated with a multitude of gene expression changes and is a prerequisite for embryo implantation. We reason that the process of decidualization involves a cascade of changes in transcriptional regulators. Our prior studies have found defective decidualization of PE-DSCs as reflected by low prolactin (PRL) levels and other decidualization markers. Transcription factor array analysis identified inhibitor of DNA binding (ID1) and FOXO1 as top differentially expressed genes during decidualization. Unlike ID1, FOXO1 involvement in decidualization has been established. We hypothesized that ID1 plays a major role in regulating stromal cell decidualization. Our data shows basal ID1 mRNA expression is significantly higher in PE DSCs. Cyclic AMP-mediated decidualization significantly upregulates ID1 mRNA expression in DSCs and siRNA-mediated knockdown of ID1 significantly interferes with decidualization as shown by a reduction in PRL and FOXO1 expression, and morphologic criteria. Thus ID1 may serve as a master regulator of stromal cell differentiation and defects in ID1 expression may affect decidualization as seen in PE-DSCs.

LncRNA-LALR1 upregulates small nucleolar RNA SNORD72 to promote growth and invasion of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most prevalent cancers and currently the second leading cause of cancer-related mortality worldwide. One recent study reported that lncRNA-LALR1 promotes liver regeneration, the role and underlying mechanisms of lncRNA-LALR1 in HCC remain largely unknown. In this study, we demonstrated that lncRNA-LALR1 was significantly upregulated in HCC tissues compared with adjacent tissues and high expression of lncRNA-LALR1 was associated with advanced TNM stage, poor differentiation, and distant metastasis. RNA Fluorescence in situ hybridization analysis showed lncRNA-LALR1 was expressed not only in cytoplasm but also in nucleolus. Knockdown of lncRNA-LALR1 obviously inhibited HCC cells growth and invasion in vivo and in vitro. Besides, transcriptomic analysis and subsequent confirmation revealed that lncRNA-LALR1 upregulated small nucleolar RNA SNORD72 via binding with SNORD72 and stabilized ID2 mRNA. SNORD72 was overexpressed in HCC tissues and enhanced HCC cells proliferation, colony formation and invasion. Overexpression of SNORD72 could also stabilize ID2 mRNA and rescue the inhibitory effect of silencing lncRNA-LALR1. In conclusion, lncRNA-LALR1 is highly expressed in HCC and promotes tumor growth and invasion by upregulating SNORD72 to stabilize ID2 mRNA, implying that lncRNA-LALR1 might be a novel target for intervention of HCC.

12 A FUNCTIONAL TL1A/DR3 SYSTEM IS CRUCIAL FOR OPTIMAL GENERATION OF PATHOGENIC TH9 CELLS IN MURINE CROHN’S DISEASE-LIKE ILEITIS

Abstract Background Despite numerous therapeutic advancements, inflammatory bowel disease (IBD) remains a major health burden due to the inefficiency of conventional therapies. We recently demonstrated the role of death receptor 3 (DR3), a member of the tumor necrosis factor receptor (TNFR) superfamily and receptor for the cytokine TL1A, in regulating the balance between effector [T helper type 1 (TH)1,TH2,TH17] and regulatory T cells during murine Crohn’s disease (CD)-like ileitis. New evidence suggests a potential role of IL-9-secreting TH9 cells in the pathogenesis of IBD. However, the role of the TL1A/DR3 system in the differentiation and function of TH9 cells in CD is not fully understood. Thus, here, we investigated the role of a functional DR3 receptor in disease progression and activation of downstream signaling pathways relevant to TH9 cell differentiation and pathogenicity. Methods Ileal tissues were collected from 20-wk SAMP/YitFc (SAMP,WT) and DR3×SAMP (KO) mice, and analyzed by H&amp;E, RT-qPCR and ELISA. CD4+ cells were purified by MACS sorting from mesenteric lymph nodes (MLNs) and spleens of WT and KO mice. TH9 cell were generated in medium supplemented with IL-4, TGF-β and TL1A. TH9 cells were analyzed by flow cytometry and cell supernatants by ELISA. TH9 cells (5x105) were adoptively transferred by i.p. injection into Rag2-/- mice, which were euthanized after 6-weeks. Colons were analyzed by H&amp;E and MLNs were immunophenotyped by flow cytometry. Results Lack of DR3 ameliorated ileitis in SAMP (histologic score:5.2±1.3vs17.2±3.1, P≤0.0001, n=6), reduced of ∼ 50% the expression of Baft3, PU.1, il-9 mRNAs and IL-9 protein (P≤0.003, n=12), and 3-fold increased Id3 mRNA (P&amp;lt;0.0007,n=12) in small intestinal tissues. CD4+-enriched TH9 cells from KO mice secreted 2-fold lower IL-9 and TNF (P≤0.0002,n=8), and 5-fold higher IL-10 protein level (P&amp;lt;0.0001, n=8) than those from WT mice. Using the Rag2-/- T-cell transfer model of chronic colitis, we found that recipients of TH9 cells from KO donors developed less severe colitis (histologic score: 0.9±0.1vs3.9±0.8, P=0.005, n=5) and retained only half of the frequency of circulating TH9 cells in MLNs (P≤0.02,n=5) compared to those receiving WT TH9 cells, at 6-week after adoptive transfer. A similar experiment is currently ongoing to verify the impact of WT and KO TH9 cells on ileo-colitis development in SAMP×Rag2-/- mice. Conclusions The TL1A/DR3 system heavily contributes to IL-9-signaling pathway activation and it is required for the secretion of higher amount of IL-9 protein by TH9 cells in SAMP mice. KO TH9 cells were less colitogenic that those isolated from WT mice, indicating a crucial role of functional DR3 receptor in TH9 pathogenicity. Collectively, our results hold great translational significance by showing that modulation of DR3 signaling may be a novel therapeutic target for the treatment of CD.

Bone morphogenetic protein 2 promotes human trophoblast cell invasion and endothelial-like tube formation through ID1-mediated upregulation of IGF binding protein-3.

Extravillous cytotrophoblasts (EVTs) invade into the uterine wall and remodel spiral arteries for proper placentation. Studies from us and others have demonstrated that the transforming growth factor-β superfamily member bone morphogenetic protein 2 (BMP2) plays important roles in endometrial decidualization and trophoblast cell invasion. However, BMP2 has also been shown to regulate endothelial cell migration and capillary-like tube formation, as has its downstream signaling molecule inhibitor of DNA binding 1 (ID1). Interestingly, insulin-like growth factor binding protein 3 (IGFBP3) also promotes cell migration and angiogenesis in endothelial precursor cell. Moreover, Id1 has a regulatory effect on Igfbp3 expression in rat prostate epithelial cells. However, whether ID1 and IGFBP3 are integrated in BMP2 signaling and involved in the regulation of trophoblast invasive and endovascular differentiation remains unknown. The objective of our study was to examine the effects of BMP2 on ID1 and IGFBP3 expression and their roles in BMP2-regulated human trophoblast invasion and endothelial-like tube formation. Primary and immortalized (HTR8/SVneo) cultures of human trophoblast cells were employed as study models. BMP2 treatment increased ID1 and IGFBP3 mRNA and protein levels in HTR8/SVneo and primary human EVT cells. Intriguingly, ID1 was essential for BMP2-induced IGFBP3 upregulation in both study models, and BMP2-induced trophoblast invasion was attenuated by knockdown of either ID1 or IGFBP3. In addition, BMP2 significantly increased endothelial-like tube formation and knockdown of ID1 and IGFBP3 reduced basal and BMP2-induced tube formation in HTR8/SVneo cells. Similarly, BMP2 increased placenta growth factor (PlGF) production in HTR8/SVneo cells and these effects were attenuated by knockdown of ID1 or IGFBP3. Our results reveal that BMP2 promotes trophoblast cell invasion and endothelial-like tube formation by ID1-mediated IGFBP3 upregulation.