scholarly journals GNA13, a Novel Component of the GPR84/Beta-Catenin Signaling Axis in AML Stem Cells, Regulates the Maintenance of MLLAF9 Leukemogenesis

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3577-3577
Author(s):  
Philipp A Dietrich ◽  
Murray D Norris ◽  
Jenny Yingzi Wang

Abstract Beta-catenin is required for the establishment of leukemic stem cells (LSC) in mixed lineage leukemia (MLL)-rearranged acute myeloid leukemia (AML). Targeted inhibition of beta-catenin signaling has been hampered by the lack of pathway components amenable to pharmacological inhibition. Our recent study has identified a new beta-catenin regulator, GPR84, a member of the G protein-coupled receptor family that represents a highly tractable class of drug targets. Since no GPR84-specific anti-cancer compound has been developed to date, we aim to further delineate the GPR84/beta-catenin axis in order to inhibit other components of this signaling pathway pharmacologically. Preliminary data from our lab has implicated GNA13 as a potential downstream target gene of GPR84. In this study we sought to further examine the involvement of GNA13 in the GPR84/beta-catenin signaling axis. Functional studies showed that shRNA-mediated ablation of GNA13 significantly decreased the capacity of MLLAF9-LSC to form colonies in vitro (P=0.0184). We further demonstrated that GNA13 inhibition in LSC induced a significant G1 cell cycle arrest in vitro (P=0.0192). Subsequent in vivo studies showed that GNA13 downregulation in MLLAF9-LSC significantly delayed the onset of AML (P=0.0016) and significantly decreased LSC proliferation (P=0.0066). Hence GNA13 inhibition mimics the previously described GPR84-deficient phenotype in MLLAF9-LSC (Blood 2013;122:3781). In contrast, the GPR84-deficient phenotype could be rescued in MLLAF9-LSC by GNA13 overexpression in vitro (P=0.0130) and in vivo (P=0.0012). Further analysis showed that there was a significant increase in the mitotic index of GPR84-deficient LSC transduced with GNA13 cDNA in vitro, evidenced by an increase in G2/M-phase accumulation (P=0.0030) and p-histone H3 (P=0.0040). In addition, our data demonstrated a significant increase in BrdU incorporation of GPR84-deficient LSC overexpressing GNA13 in vivo (P<0.0001). In conclusion, our studies have identified GNA13, a novel component of the GPR84/beta-catenin axis. Since this pathway is pivotal for MLLAF9 AML maintenance by sustaining LSC self-renewal, targeting the GPR84/GNA13/beta-catenin signaling axis may provide a novel and promising strategy for improving the therapy and outcome of AML patients. Disclosures No relevant conflicts of interest to declare.

2009 ◽  
Vol 21 (03) ◽  
pp. 149-155 ◽  
Author(s):  
Hsu-Wei Fang

Cartilage injuries may be caused by trauma, biomechanical imbalance, or degenerative changes of joint. Unfortunately, cartilage has limited capability to spontaneous repair once damaged and may lead to progressive damage and degeneration. Cartilage tissue-engineering techniques have emerged as the potential clinical strategies. An ideal tissue-engineering approach to cartilage repair should offer good integration into both the host cartilage and the subchondral bone. Cells, scaffolds, and growth factors make up the tissue engineering triad. One of the major challenges for cartilage tissue engineering is cell source and cell numbers. Due to the limitations of proliferation for mature chondrocytes, current studies have alternated to use stem cells as a potential source. In the recent years, a lot of novel biomaterials has been continuously developed and investigated in various in vitro and in vivo studies for cartilage tissue engineering. Moreover, stimulatory factors such as bioactive molecules have been explored to induce or enhance cartilage formation. Growth factors and other additives could be added into culture media in vitro, transferred into cells, or incorporated into scaffolds for in vivo delivery to promote cellular differentiation and tissue regeneration.Based on the current development of cartilage tissue engineering, there exist challenges to overcome. How to manipulate the interactions between cells, scaffold, and signals to achieve the moderation of implanted composite differentiate into moderate stem cells to differentiate into hyaline cartilage to perform the optimum physiological and biomechanical functions without negative side effects remains the target to pursue.


2017 ◽  
Vol 242 (18) ◽  
pp. 1765-1771 ◽  
Author(s):  
Guinea BC Cardoso ◽  
Erivelto Chacon ◽  
Priscila GL Chacon ◽  
Pedro Bordeaux-Rego ◽  
Adriana SS Duarte ◽  
...  

Our hypothesis was to investigate the fatty acid potential as a bone induction factor. In vitro and in vivo studies were performed to evaluate this approach. Oleic acid was used in a 0.5 wt.% concentration. Polycaprolactone was used as the polymeric matrix by combining solvent-casting and particulate-leaching techniques, with a final porosity of 70 wt.%, investigated by SEM images. Contact angle measurements were produced to investigate the influence of oleic acid on polycaprolactone chains. Cell culture was performed using adipocyte-derived stem cells to evaluate biocompatibility and bioactivity properties. In addition, in vivo studies were performed to evaluate the induction potential of oleic acid addition. Adipocyte-derived stem cells were used to provide differentiation after 21 days of culture. Likewise, information were obtained with in vivo data and cellular invagination was observed on both scaffolds (polycaprolactone and polycaprolactone /oleic acid); interestingly, the scaffold with oleic acid addition demonstrated that cellular migrations are not related to the surrounding tissue, indicating bioactive potential. Our hypothesis is that fatty acid may be used as a potential induction factor for bone tissue engineering. The study’s findings indicate oleic acid as a possible agent for bone induction, according to data on cell differentiation, proliferation, and migration. Impact statement The biomaterial combined in this study on bone regeneration is innovative and shows promising results in the treatment of bone lesions. Polycaprolactone (PCL) and oleic acid have been studied separately. In this research, we combined biomaterials to assess the stimulus and the speed of bone healing.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Yanli Liu ◽  
Fen Yang ◽  
Shengying Liang ◽  
Qing Liu ◽  
Sulei Fu ◽  
...  

Peripheral nerve injuries are typically caused by either trauma or medical disorders, and recently, stem cell-based therapies have provided a promising treatment approach. Menstrual blood-derived endometrial stem cells (MenSCs) are considered an ideal therapeutic option for peripheral nerve repair due to a noninvasive collection procedure and their high proliferation rate and immunological tolerance. Here, we successfully isolated MenSCs and examined their biological characteristics including their morphology, multipotency, and immunophenotype. Subsequent in vitro studies demonstrated that MenSCs express high levels of neurotrophic factors, such as NT3, NT4, BDNF, and NGF, and are capable of transdifferentiating into glial-like cells under conventional induction conditions. Moreover, upregulation of N-cadherin (N-cad) mRNA and protein expression was observed after neurogenic differentiation. In vivo studies clearly showed that N-cad knockdown via in utero electroporation perturbed the migration and maturation of mouse neural precursor cells (NPCs). Finally, a further transfection assay also confirmed that N-cad upregulation in MenSCs results in the expression of S100. Collectively, our results confirmed the paracrine effect of MenSCs on neuroprotection as well as their potential for transdifferentiation into glial-like cells and demonstrated that N-cad upregulation promotes the neurogenic differentiation of MenSCs, thereby providing support for transgenic MenSC-based therapy for peripheral nerve injury.


2021 ◽  
pp. 1-11
Author(s):  
Yuzaburo Shimizu ◽  
Joy Gumin ◽  
Feng Gao ◽  
Anwar Hossain ◽  
Elizabeth J. Shpall ◽  
...  

OBJECTIVE Delta-24-RGD is an oncolytic adenovirus that is capable of replicating in and killing human glioma cells. Although intratumoral delivery of Delta-24-RGD can be effective, systemic delivery would improve its clinical application. Bone marrow–derived human mesenchymal stem cells (BM-hMSCs) obtained from healthy donors have been investigated as virus carriers. However, it is unclear whether BM-hMSCs can be derived from glioma patients previously treated with marrow-toxic chemotherapy or whether such BM-hMSCs can deliver oncolytic viruses effectively. Herein, the authors undertook a prospective clinical trial to determine the feasibility of obtaining BM-hMSCs from patients with recurrent malignant glioma who were previously exposed to marrow-toxic chemotherapy. METHODS The authors enrolled 5 consecutive patients who had been treated with radiation therapy and chemotherapy. BM aspirates were obtained from the iliac crest and were cultured to obtain BM-hMSCs. RESULTS The patient-derived BM-hMSCs (PD-BM-hMSCs) had a morphology similar to that of healthy donor–derived BM-hMSCs (HD-BM-hMSCs). Flow cytometry revealed that all 5 cell lines expressed canonical MSC surface markers. Importantly, these cultures could be made to differentiate into osteocytes, adipocytes, and chondrocytes. In all cases, the PD-BM-hMSCs homed to intracranial glioma xenografts in mice after intracarotid delivery as effectively as HD-BM-hMSCs. The PD-BM-hMSCs loaded with Delta-24-RGD (PD-BM-MSC-D24) effectively eradicated human gliomas in vitro. In in vivo studies, intravascular administration of PD-BM-MSC-D24 increased the survival of mice harboring U87MG gliomas. CONCLUSIONS The authors conclude that BM-hMSCs can be acquired from patients previously treated with marrow-toxic chemotherapy and that these PD-BM-hMSCs are effective carriers for oncolytic viruses.


Development ◽  
2001 ◽  
Vol 128 (18) ◽  
pp. 3405-3413 ◽  
Author(s):  
Adi Inbal ◽  
Naomi Halachmi ◽  
Charna Dibner ◽  
Dale Frank ◽  
Adi Salzberg

Homothorax (HTH) is a homeobox-containing protein, which plays multiple roles in the development of the embryo and the adult fly. HTH binds to the homeotic cofactor Extradenticle (EXD) and translocates it to the nucleus. Its function within the nucleus is less clear. It was shown, mainly by in vitro studies, that HTH can bind DNA as a part of ternary HTH/EXD/HOX complexes, but little is known about the transcription regulating function of HTH-containing complexes in the context of the developing fly. Here we present genetic evidence, from in vivo studies, for the transcriptional-activating function of HTH. The HTH protein was forced to act as a transcriptional repressor by fusing it to the Engrailed (EN) repression domain, or as a transcriptional activator, by fusing it to the VP16 activation domain, without perturbing its ability to translocate EXD to the nucleus. Expression of the repressing form of HTH in otherwise wild-type imaginal discs phenocopied hth loss of function. Thus, the repressing form was working as an antimorph, suggesting that normally HTH is required to activate the transcription of downstream target genes. This conclusion was further supported by the observation that the activating form of HTH caused typical hth gain-of-function phenotypes and could rescue hth loss-of-function phenotypes. Similar results were obtained with XMeis3, the Xenopus homologue of HTH, extending the known functional similarity between the two proteins. Competition experiments demonstrated that the repressing forms of HTH or XMeis3 worked as true antimorphs competing with the transcriptional activity of the native form of HTH. We also describe the phenotypic consequences of HTH antimorph activity in derivatives of the wing, labial and genital discs. Some of the described phenotypes, for example, a proboscis-to-leg transformation, were not previously associated with alterations in HTH activity. Observing the ability of HTH antimorphs to interfere with different developmental pathways may direct us to new targets of HTH. The HTH antimorph described in this work presents a new means by which the transcriptional activity of the endogenous HTH protein can be blocked in an inducible fashion in any desired cells or tissues without interfering with nuclear localization of EXD.


2019 ◽  
Vol 28 (12) ◽  
pp. 1490-1506 ◽  
Author(s):  
Yu You ◽  
Di-guang Wen ◽  
Jian-ping Gong ◽  
Zuo-jin Liu

Liver transplantation has been deemed the best choice for end-stage liver disease patients but immune rejection after surgery is still a serious problem. Patients have to take immunosuppressive drugs for a long time after liver transplantation, and this often leads to many side effects. Mesenchymal stem cells (MSCs) gradually became of interest to researchers because of their powerful immunomodulatory effects. In the past, a large number of in vitro and in vivo studies have demonstrated the great potential of MSCs for participation in posttransplant immunomodulation. In addition, MSCs also have properties that may potentially benefit patients undergoing liver transplantation. This article aims to provide an overview of the current understanding of the immunomodulation achieved by the application of MSCs in liver transplantation, to discuss the problems that may be encountered when using MSCs in clinical practice, and to describe some of the underlying capabilities of MSCs in liver transplantation. Cell–cell contact, soluble molecules, and exosomes have been suggested to be critical approaches to MSCs’ immunoregulation in vitro; however, the exact mechanism, especially in vivo, is still unclear. In recent years, the clinical safety of MSCs has been proven by a series of clinical trials. The obstacles to the clinical application of MSCs are decreasing, but large sample clinical trials involving MSCs are still needed to further study their clinical effects.


2015 ◽  
Vol 39 (5) ◽  
pp. 778-782 ◽  
Author(s):  
Kyung Hee Min ◽  
Jin Hwan Byun ◽  
Chan Yeong Heo ◽  
Eun Hee Kim ◽  
Hye Yeon Choi ◽  
...  

2013 ◽  
Vol 59 (12) ◽  
pp. 1708-1721 ◽  
Author(s):  
Emma Raitoharju ◽  
Niku Oksala ◽  
Terho Lehtimäki

BACKGROUND MicroRNAs (miRNA, miR) are noncoding RNAs that regulate gene expression by hindering translation. miRNA expression profiles have been shown to differ in vivo and in vitro in many cellular processes associated with cardiovascular diseases (CVDs). The progression of CVDs has also been shown to alter the blood miRNA profile in humans. CONTENT We summarize the results of animal and cell experiments concerning the miRNA profile in the atherosclerotic process and the changes which occur in the blood miRNA profile of individuals with CVD. We also survey the relationship of these CVD-related miRNAs and their expression in the human advanced atherosclerotic plaque, thereby providing more insight into miRNA function in human atherosclerotic lesions. The miRNAs miR-126, -134, -145, -146a, -198, -210, -340*, and -92a were found to be expressed differently in the blood of individuals affected and unaffected by CVD. These differences paralleled those seen in tissue comparisons of miRNA expression in advanced atherosclerotic plaques and healthy arteries. Furthermore, several miRNAs associated with atherosclerosis in in vitro studies (such as miR-10a, -126, -145, -146a/b, -185, -210, and -326) were expressed in plaques in a similar pattern as was predicted by the in vitro experiments. The clinical implications of miRNAs in atherosclerosis as biomarkers and as possible drug targets are also reviewed. SUMMARY miRNA profiles in in vitro and in vivo studies as well as in human peripheral blood are quite representative of the miRNA expression in human atherosclerotic plaques. miRNAs appear promising in terms of future clinical applications.


2019 ◽  
Vol 21 (1) ◽  
pp. 31-40
Author(s):  
Mariné Ortiz-Magdaleno DDS, MSc, PhD ◽  
Ana Isabel Romo-Tobías DDS ◽  
Fernando Romo-Ramírez DDS, MSc ◽  
Diana María Escobar DDS, MSc, PhD ◽  
Héctor Flores-Reyes DDS, MSc, PhD ◽  
...  

The success of tissue engineering in combination with tissue regeneration depends on the behavior and cellular activity in the biological processes developed within a structure that functions as a support, better known as scaffolds, or directly at the site of the injury. The cell-cell and cell-biomaterial interaction are key factors for the induction of a specific cell behavior, together with the bioactive factors that allow the formation of the desired tissue. Mesenchymal Stem Cells (MSC) can be isolated from the umbilical cord and bone marrow; however, the behavior of Dental Pulp Stem Cells (DPSC) has been shown to have a high potential for the formation of bone tissue, and these cells have even been able to induce the process of angiogenesis. Advances in periodontal regeneration, dentin-pulp complex, and craniofacial bone defects through the induction of MSC obtained from tooth structures in in vitro-in vivo studies have permitted the obtaining of clinical evidence of the achievements obtained to date.


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