A Tumor Suppressor microRNA Defines the Leukemic Hierarchy in Acute Myeloid Leukemia

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3653-3653
Author(s):  
Edith Schneider ◽  
Anna Staffas ◽  
Linda Roehner ◽  
Christian Buske ◽  
Lars Bullinger ◽  
...  

Abstract In order to identify functionally relevant microRNAs (miRNA) in AML, we profiled global miRNA expression in a murine AML progression model based on Hoxa9 and Meis1 overexpression. We found miR-155 and miR-708 as the most significantly upregulated miRNA species in leukemic Hoxa9/Meis1 cells compared to the preleukemic Hoxa9/ctrl cells (both p<0.01). Subsequent analysis of various AML subtypes (CN-AML, t(11q23), t(8;21), t(15;17), n=38) showed significantly elevated levels of miR-155 and miR-708 in all tested samples (n=5-10) compared to total bone marrow from healthy donors, indicating potential oncogenic roles for these miRNAs. We further investigated, in vivo, the role of miR-155 and miR-708 in AML by retroviral overexpression with Hoxa9 in murine bone marrow (mbm) cells followed by syngeneic transplantation. Overexpression of miR-155 in conjunction with Hoxa9 (Hoxa9/miR-155) caused a significantly accelerated onset of a myelomonocytic leukemia within 93 days (survival 93±23 days, p<0.0001), but still a less aggressive course of disease compared to mice transplanted with Hoxa9/Meis1 (survival 36±4 days, p<0.0001). We then hypothesized that the combination of miR-155 and miR-708 could further replace the oncogenic potential of Meis1. Therefore, mbm cells were retrovirally transduced with Hoxa9, miR-155 and miR-708 (Hoxa9/155/708) or Hoxa9 and miR-708 (Hoxa9/miR-708) and functionally analyzed in vitro and in vivo. To our surprise, miR-708 abrogated the leukemogenic effect of Hoxa9, alone or in combination with Hoxa9/miR-155 in vivo (p=0.0117, p<0.0001, the mice were sacrificed after 197 days), with little or no engraftment. To understand why miR-708, a potent tumor suppressor miRNA, is upregulated in the highly aggressive Hoxa9/Meis1 AML cells, we first showed in vivo that miR-708 does not impair the development of AML by Hoxa9/Meis1 cells. In order to explore the role of miR-708 in leukemia initiating cells (LIC), we FACS-sorted subpopulations enriched for LIC based on c-kit, Mac-1 and Gr-1 expression within the Hoxa9/Meis1 cells. Of the three subpopulations (c-kit+ Gr-1- Mac-1-, c-kit+ Gr-1+ Mac-1+, c-kit- Gr-1+ Mac-1+) the transplanted c-kit+ Gr-1- Mac-1- cells caused a significantly shorter survival (survival 36 days, range: 32-37d) compared to the other sorted subpopulations (p=0.0072 and p=0.0021, respectively), whereas the c-kit- Gr-1+ Mac-1+ subpopulation exhibited the longest survival (survival 44 days, range: 42-51d). Based on these findings, we measured miR-708 and miR-155 levels in the sorted Hoxa9/Meis1 subpopulations by qRT-PCR. Strikingly, no difference compared to bulk cells was detected for miR-155, highlighting its role as an oncogenic driver in all subpopulations. In contrast, miR-708 showed a distinct expression pattern with lower expression in the LIC-enriched c-kit+ Gr-1- Mac-1- subpopulation compared to bulk (p=0.032), allowing discernment of the LIC enriched population and highlighting its role as an orchestrator of the leukemic hierarchy. Adapted from these findings, we developed an AML 4-step model (Hoxa9/miR-708, Hoxa9/ctrl, Hoxa9/miR-155, Hoxa9/Meis1) based on four immortalized Hoxa9 based cell lines with completely different in vivo properties ranging from no engraftment to induction of highly aggressive AML. Considering the central role of Hoxa9/Meis1 in AML, we demonstrate, for the first time, the concept of a tumor suppressor miRNA that stratifies the leukemic hierarchy driven by an oncogenic miRNA. Moreover, we present a new AML 4-step model as a novel tool that will allow detailed investigation of the impact of new oncogenes at every step of leukemogenesis. Disclosures Buske: CELLTRION, Inc.: Consultancy, Honoraria.

1988 ◽  
Vol 8 (12) ◽  
pp. 5116-5125
Author(s):  
J W Belmont ◽  
G R MacGregor ◽  
K Wager-Smith ◽  
F A Fletcher ◽  
K A Moore ◽  
...  

Multiple replication-defective retrovirus vectors were tested for their ability to transfer and express human adenosine deaminase in vitro and in vivo in a mouse bone marrow transplantation model. High-titer virus production was obtained from vectors by using both a retrovirus long terminal repeat promoter and internal transcriptional units with human c-fos and herpes virus thymidine kinase promoters. After infection of primary murine bone marrow with one of these vectors, human adenosine deaminase was detected in 60 to 85% of spleen colony-forming units and in the blood of 14 of 14 syngeneic marrow transplant recipients. This system offers the opportunity to assess methods for increasing efficiency of gene transfer, for regulation of expression of foreign genes in hematopoietic progenitors, and for long-term measurement of the stability of expression in these cells.


Author(s):  
Sha Sumei ◽  
Kong Xiangyun ◽  
Chen Fenrong ◽  
Sun Xueguang ◽  
Hu Sijun ◽  
...  

Background/AimsThe role of DHRS3 in human cancer remains unclear. Our study explored the role of DHRS3 in gastric cancer (GC) and its clinicopathological significance and associated mechanisms.MaterialsBisulfite-assisted genomic sequencing PCR and a Mass-Array system were used to evaluate and quantify the methylation levels of the promoter. The expression levels and biological function of DHRS3 was examined by both in vitro and in vivo assays. A two-way hierarchical cluster analysis was used to classify the methylation profiles, and the correlation between the methylation status of the DHRS3 promoter and the clinicopathological characteristics of GC were then assessed.ResultsThe DHRS3 promoter was hypermethylated in GC samples, while the mRNA and protein levels of DHRS3 were significantly downregulated. Ectopic expression of DHRS3 in GC cells inhibited cell proliferation and migration in vitro, decreased tumor growth in vivo. DHRS3 methylation was correlated with histological type and poor differentiation of tumors. GC patients with high degrees of CpG 9.10 methylation had shorter survival times than those with lower methylation.ConclusionDHRS3 was hypermethylated and downregulated in GC patients. Reduced expression of DHRS3 is implicated in gastric carcinogenesis, which suggests DHRS3 is a tumor suppressor.


2008 ◽  
Vol 205 (8) ◽  
pp. 1929-1938 ◽  
Author(s):  
César Muñoz-Fontela ◽  
Salvador Macip ◽  
Luis Martínez-Sobrido ◽  
Lauren Brown ◽  
Joseph Ashour ◽  
...  

Tumor suppressor p53 is activated by several stimuli, including DNA damage and oncogenic stress. Previous studies (Takaoka, A., S. Hayakawa, H. Yanai, D. Stoiber, H. Negishi, H. Kikuchi, S. Sasaki, K. Imai, T. Shibue, K. Honda, and T. Taniguchi. 2003. Nature. 424:516–523) have shown that p53 is also induced in response to viral infections as a downstream transcriptional target of type I interferon (IFN) signaling. Moreover, many viruses, including SV40, human papillomavirus, Kaposi's sarcoma herpesvirus, adenoviruses, and even RNA viruses such as polioviruses, have evolved mechanisms designated to abrogate p53 responses. We describe a novel p53 function in the activation of the IFN pathway. We observed that infected mouse and human cells with functional p53 exhibited markedly decreased viral replication early after infection. This early inhibition of viral replication was mediated both in vitro and in vivo by a p53-dependent enhancement of IFN signaling, specifically the induction of genes containing IFN-stimulated response elements. Of note, p53 also contributed to an increase in IFN release from infected cells. We established that this p53-dependent enhancement of IFN signaling is dependent to a great extent on the ability of p53 to activate the transcription of IFN regulatory factor 9, a central component of the IFN-stimulated gene factor 3 complex. Our results demonstrate that p53 contributes to innate immunity by enhancing IFN-dependent antiviral activity independent of its functions as a proapoptotic and tumor suppressor gene.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Linli Li ◽  
Yiqun He ◽  
Han Tang ◽  
Wei Mao ◽  
Haofei Ni ◽  
...  

Background. Angiogenesis is a prerequisite step to achieve the success of bone regeneration by tissue engineering technology. Previous studies have shown the role of cerebrospinal fluid pulsation (CSFP) stress in the reconstruction of tissue-engineered laminae. In this study, we investigated the role of CSFP stress in the angiogenesis of tissue-engineered laminae. Methods. For the in vitro study, a CSFP bioreactor was used to investigate the impact of CSFP stress on the osteogenic mesenchymal stem cells (MSCs). For the in vivo study, forty-eight New Zealand rabbits were randomly divided into the CSFP group and the Non-CSFP group. Tissue-engineered laminae (TEL) was made by hydroxyapatite-collagen I scaffold and osteogenic MSCs and then implanted into the lamina defect in the two groups. The angiogenic and osteogenic abilities of newborn laminae were examined with histological staining, qRT-PCR, and radiological analysis. Results. The in vitro study showed that CSFP stress could promote the vascular endothelial growth factor A (VEGF-A) expression levels of osteogenic MSCs. In the animal study, the expression levels of angiogenic markers in the CSFP group were higher than those in the Non-CSFP group; moreover, in the CSFP group, their expression levels on the dura mater surface, which are closer to the CSFP stress stimulation, were also higher than those on the paraspinal muscle surface. The expression levels of osteogenic markers in the CSFP group were also higher than those in the Non-CSFP group. Conclusion. CSFP stress could promote the angiogenic ability of osteogenic MSCs and thus promote the angiogenesis of tissue-engineered laminae. The pretreatment of osteogenic MSC with a CSFP bioreactor may have important implications for vertebral lamina reconstruction with a tissue engineering technique.


2019 ◽  
Vol 20 (11) ◽  
pp. 2675 ◽  
Author(s):  
Nicholas Wilson ◽  
Robert Steadman ◽  
Ilaria Muller ◽  
Mohd Draman ◽  
D. Aled Rees ◽  
...  

Hyaluronan (HA), an extra-cellular matrix glycosaminoglycan, may play a role in mesenchymal stem cell differentiation to fat but results using murine models and cell lines are conflicting. Our previous data, illustrating decreased HA production during human adipogenesis, suggested an inhibitory role. We have investigated the role of HA in adipogenesis and fat accumulation using human primary subcutaneous preadipocyte/fibroblasts (PFs, n = 12) and subjects of varying body mass index (BMI). The impact of HA on peroxisome proliferator-activated receptor gamma (PPARγ) expression was analysed following siRNA knockdown or HA synthase (HAS)1 and HAS2 overexpression. PFs were cultured in complete or adipogenic medium (ADM) with/without 4-methylumbelliferone (4-MU = HA synthesis inhibitor). Adipogenesis was evaluated using oil red O (ORO), counting adipogenic foci, and measurement of a terminal differentiation marker. Modulating HA production by HAS2 knockdown or overexpression increased (16%, p < 0.04) or decreased (30%, p = 0.01) PPARγ transcripts respectively. The inhibition of HA by 4-MU significantly enhanced ADM-induced adipogenesis with 1.52 ± 0.18- (ORO), 4.09 ± 0.63- (foci) and 2.6 ± 0.21-(marker)-fold increases compared with the controls, also increased PPARγ protein expression (40%, (p < 0.04)). In human subjects, circulating HA correlated negatively with BMI and triglycerides (r = −0.396 (p = 0.002), r = −0.269 (p = 0.038), respectively), confirming an inhibitory role of HA in human adipogenesis. Thus, enhancing HA action may provide a therapeutic target in obesity.


1993 ◽  
Vol 16 (5_suppl) ◽  
pp. 8-12 ◽  
Author(s):  
A.M. Vannucchi ◽  
A. Bosi ◽  
A. Grossi ◽  
S. Guidi ◽  
R. Saccardi ◽  
...  

The issue of the role of erythropoietin (Epo) in the erythroid reconstitution after bone marrow transplantation (BMT) has been addressed in several recent studies. A defective Epo production in response to anemia has been shown to occur in patients undergoing allogeneic BMT unlike in most of those subjected to an autologous rescue. The factors involved in the inadeguate Epo production in BMT are discussed, with particular attention to the role of the immunosuppressive drug cyclosporin-A, which has been shown to inhibit Epo production in both in vivo and in vitro models. The observation of defective Epo production eventually led to the development of clinical trials of recombinant human Epo (rhEpo) administration in BMT patients; the aims of these studies were to stimulate erythroid engraftment, hence reducing blood transfusion exposure. Although the number of patients studied up to now is relatively small, a benefit from rhEpo administration in terms of accelerated erythroid engraftment seems very likely, and it may also be associated with decreased transfusional needs in most treated patients. However, further studies are needed to better define indications, dosages and schedules of rhEpo in BMT patients.


Blood ◽  
2020 ◽  
Vol 136 (4) ◽  
pp. 501-515 ◽  
Author(s):  
Kunpeng Wu ◽  
Yan Yuan ◽  
Huihui Yu ◽  
Xin Dai ◽  
Shu Wang ◽  
...  

Abstract The diversity of the human microbiome heralds the difference of the impact that gut microbial metabolites exert on allogenic graft-versus-host (GVH) disease (GVHD), even though short-chain fatty acids and indole were demonstrated to reduce its severity. In this study, we dissected the role of choline-metabolized trimethylamine N-oxide (TMAO) in the GVHD process. Either TMAO or a high-choline diet enhanced the allogenic GVH reaction, whereas the analog of choline, 3,3-dimethyl-1-butanol reversed TMAO-induced GVHD severity. Interestingly, TMAO-induced alloreactive T-cell proliferation and differentiation into T-helper (Th) subtypes was seen in GVHD mice but not in in vitro cultures. We thus investigated the role of macrophage polarization, which was absent from the in vitro culture system. F4/80+CD11b+CD16/32+ M1 macrophage and signature genes, IL-1β, IL-6, TNF-α, CXCL9, and CXCL10, were increased in TMAO-induced GVHD tissues and in TMAO-cultured bone marrow–derived macrophages (BMDMs). Inhibition of the NLRP3 inflammasome reversed TMAO-stimulated M1 features, indicating that NLRP3 is the key proteolytic activator involved in the macrophage’s response to TMAO stimulation. Consistently, mitochondrial reactive oxygen species and enhanced NF-κB nuclear relocalization were investigated in TMAO-stimulated BMDMs. In vivo depletion of NLRP3 in GVHD recipients not only blocked M1 polarization but also reversed GVHD severity in the presence of TMAO treatment. In conclusion, our data revealed that TMAO-induced GVHD progression resulted from Th1 and Th17 differentiation, which is mediated by the polarized M1 macrophage requiring NLRP3 inflammasome activation. It provides the link among the host choline diet, microbial metabolites, and GVH reaction, shedding light on alleviating GVHD by controlling choline intake.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Qing Xia ◽  
Tao Han ◽  
Pinghua Yang ◽  
Ruoyu Wang ◽  
Hengyu Li ◽  
...  

Background. MicroRNAs (miRNAs) play a critical role in the regulation of cancer stem cells (CSCs). However, the role of miRNAs in liver CSCs has not been fully elucidated. Methods. Real-time PCR was used to detect the expression of miR-miR-28-5p in liver cancer stem cells (CSCs). The impact of miR-28-5p on liver CSC expansion was investigated both in vivo and in vitro. The correlation between miR-28-5p expression and sorafenib benefits in HCC was further evaluated in patient-derived xenografts (PDXs). Results. Our data showed that miR-28-5p was downregulated in sorted EpCAM- and CD24-positive liver CSCs. Biofunctional investigations revealed that knockdown miR-28-5p promoted liver CSC self-renewal and tumorigenesis. Consistently, miR-28-5p overexpression inhibited liver CSC’s self-renewal and tumorigenesis. Mechanistically, we found that insulin-like growth factor-1 (IGF-1) was a direct target of miR-28-5p in liver CSCs, and the effects of miR-28-5p on liver CSC’s self-renewal and tumorigenesis were dependent on IGF-1. The correlation between miR-28-5p and IGF-1 was confirmed in human HCC tissues. Furthermore, the miR-28-5p knockdown HCC cells were more sensitive to sorafenib treatment. Analysis of patient-derived xenografts (PDXs) further demonstrated that the miR-28-5p may predict sorafenib benefits in HCC patients. Conclusion. Our findings revealed the crucial role of the miR-28-5p in liver CSC expansion and sorafenib response, rendering miR-28-5p an optimal therapeutic target for HCC.


Blood ◽  
1991 ◽  
Vol 78 (3) ◽  
pp. 720-727 ◽  
Author(s):  
R Agah ◽  
BS Charak ◽  
V Chen ◽  
A Mazumder

Abstract This work is a continuation of our studies that showed that interleukin- 2 (IL-2)-activated murine bone marrow (ABM) cells have potent cytotoxic potential against murine cytomegalovirus (MCMV)-infected targets in vitro, without loss of reconstitutive ability in vivo. Our data show that ABM cells lyse the MCMV-infected cells in vitro, at both acute and chronic stages of infection; this lysis is specific for the MCMV- infected cells. ABM cells supplemented with IL-2 therapy virtually eradicated the viral infection and prolonged the survival of MCMV- infected Balb/c mice, whether or not they were immunocompromised by irradiation (P less than .001 in both situations). Efficacy of ABM cells alone or IL-2 alone was less than the combination of ABM cells and IL-2. The efficacy of combination treatment with ABM cells and IL-2 in improving the survival of MCMV-infected mice was comparable, whether used in a preventive or a therapeutic setting. Therapy with ABM plus IL- 2 also prevented the reactivation of chronic MCMV infection after irradiation. Preliminary findings indicate that Thy-1+ and asialo GM1+ cells limited the MCMV proliferation by approximately 30% and 80%, respectively, while BM macrophages limited the proliferation of MCMV by 100%. These results suggest that BM transplantation (BMT) with ABM cells followed by IL-2 therapy may constitute a novel strategy to improve the host resistance against cytomegalovirus infection after BMT.


2020 ◽  
Author(s):  
Montserrat Lara-Velazquez ◽  
Natanael Zarco ◽  
Anna Carrano ◽  
Jordan Phillipps ◽  
Emily S Norton ◽  
...  

Abstract Background Glioblastomas (GBMs) are the most common primary brains tumors in adults with almost 100% recurrence rate. Patients with lateral ventricle proximal GBMs (LV-GBMs) exhibit worse survival compared to distal locations for reasons that remain unknown. One potential explanation is the proximity of these tumors to the cerebrospinal fluid (CSF) and its contained chemical cues that can regulate cellular migration and differentiation. We therefore investigated the role of CSF on GBM gene expression and the role of a CSF-induced gene, SERPINA3, in GBM malignancy in vitro and in vivo. Methods We utilized patient-derived CSF and primary cultures of GBM brain tumor initiating cells (BTICs). We determined the impact of SERPINA3 expression in glioma patients using TCGA database. SERPINA3 expression changes were evaluated at both the mRNA and protein levels. The effects of knockdown (KD) and overexpression (OE) of SERPINA3 on cell behavior were evaluated by transwell assay (for cell migration), and alamar blue and Ki67 (for viability and proliferation respectively). Stem cell characteristics on KD cells were evaluated by differentiation and colony formation experiments. Tumor growth was studied by intracranial and flank injections. Results GBM CSF induced a significant increase in BTIC migration accompanied by upregulation of the SERPINA3 gene. In patient samples and TCGA data we observed SERPINA3 to correlate directly with brain tumor grade and indirectly with GBM patient survival. Silencing of SERPINA3 induced a decrease in cell proliferation, migration, invasion, and stem cell characteristics, while SERPINA3 overexpression increased cell migration. In vivo, mice orthotopically-injected with SERPINA3 KD BTICs showed increased survival. Conclusions SERPINA3 plays a key role in GBM malignancy and its inhibition results in a better outcome using GBM preclinical models.


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