scholarly journals Betamethasone Induces a Unique Transcriptome in Neural Stem Cells

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A802-A802
Author(s):  
Neerupma Silswal ◽  
Joe Bean ◽  
Herschel Gupta ◽  
Fatma Talib ◽  
Suban Burale ◽  
...  

Abstract Twelve percent of pregnant women receive glucocorticoids (sGCs) to reduce the risks to reduce morbidity and mortality associated with preterm birth in infants. The two most commonly administered sGC are Dexamethasone (Dex) and Betamethasone (Beta) and they serve to decrease the severity of respiratory distress, intraventricular hemorrhage and necrotizing enterocolitis. However, repeated administration of sGC has been shown to be associated with adverse neurological outcome and depends on the type of sGCs used, dose, timing of sGCs administration and sex. We have previously shown that prenatal exposure to Dex in a murine model lead to sex specific changes in the transcription response and in the biological function of neural stem cells and to long-term changes in brain architecture and behavior. Beta is the predominant sGC used prenatally in the United States, therefore these studies investigated the cellular and molecular responses to beta exposure on the neural stem cells in-vitro and anatomical organization of the brain in-vivo. Murine NSCs were isolated from the E14.5 cerebral cortex and exposed to 10-7 M Dex, 10-7 M Beta, or Vehicle for 4 or 24 hours and the immediate and long-term impact on transcription, proliferation and neuronal, glial and oligodendrocyte differentiation examined. Affymetrix genome transcriptional analyses reveal sex specific responses to Dex vs Beta in 4 hours. In females 682 genes were differentially regulated by Dex compared to 576 by Beta. In contrast, 875 were altered by Dex and 576 by Beta in males (Fold change > +/- 1.5, P< 0.05). Select target genes were independently validated by QPCR. Ingenuity Pathway Analysis was used to identify unique and overlapping pathways that were altered by Dex vs Beta. In males, Dex uniquely altered 34 pathways including, Thyroid Hormone Metabolism, ERK5 Signaling and Opioid Signaling while Bata altered 33 pathways including, Phagasome formation, IL-7 Signaling and JAK STAT signaling. In Females, Dex altered 45 pathways including Calcium Signaling, Serotonin Receptor Signaling and Xenobiotic Signaling, while Beta altered 46 pathways including, FXR/RXR Activation, Tec Kinase Signaling and D-myo-Inositol-5-Phosphate Metabolism. Another 35 pathways were altered by both Dex and Beta but they showed differences in genes activated or repressed. Dex and Beta, both significantly altered genes involved in proliferation and differentiation therefore the biological response of NSC to sGCs stimulation in vitro and the long term consequences of sGC exposure in-vivo was compared. Distinct differences in cell proliferation, glial and oligodendrocyte differentiation were observed. These results reveal gene targets, cellular pathways and processes that are differentially altered by prenatal Dex vs Beta exposure. Our finds may provide insights into the sex specific neurological outcomes observed in children exposed to sGCs in-utero.

2019 ◽  
Vol 29 (5) ◽  
pp. 727-735 ◽  
Author(s):  
Yuhang Cao ◽  
Yingliang Zhuang ◽  
Junchen Chen ◽  
Weize Xu ◽  
Yikai Shou ◽  
...  

Abstract N 6-methyladenosine (m6A) modification of RNA is deposited by the methyltransferase complex consisting of Mettl3 and Mettl14 and erased by demethylase Fto and Alkbh5 and is involved in diverse biological processes. However, it remains largely unknown the specific function and mechanism of Fto in regulating adult neural stem cells (aNSCs). In the present study, utilizing a conditional knockout (cKO) mouse model, we show that the specific ablation of Fto in aNSCs transiently increases the proliferation of aNSCs and promotes neuronal differentiation both in vitro and in vivo, but in a long term, the specific ablation of Fto inhibits adult neurogenesis and neuronal development. Mechanistically, Fto deficiency results in a significant increase in m6A modification in Pdgfra and Socs5. The increased expression of Pdgfra and decreased expression of Socs5 synergistically promote the phosphorylation of Stat3. The modulation of Pdgfra and Socs5 can rescue the neurogenic deficits induced by Fto depletion. Our results together reveal an important function of Fto in regulating aNSCs through modulating Pdgfra/Socs5-Stat3 pathway.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sangita Biswas ◽  
Seung Hyuk Chung ◽  
Peng Jiang ◽  
Samaneh Dehghan ◽  
Wenbin Deng

Author(s):  
Fatima Aerts-Kaya

: In contrast to their almost unlimited potential for expansion in vivo and despite years of dedicated research and optimization of expansion protocols, the expansion of Hematopoietic Stem Cells (HSCs) in vitro remains remarkably limited. Increased understanding of the mechanisms that are involved in maintenance, expansion and differentiation of HSCs will enable the development of better protocols for expansion of HSCs. This will allow procurement of HSCs with long-term engraftment potential and a better understanding of the effects of the external influences in and on the hematopoietic niche that may affect HSC function. During collection and culture of HSCs, the cells are exposed to suboptimal conditions that may induce different levels of stress and ultimately affect their self-renewal, differentiation and long-term engraftment potential. Some of these stress factors include normoxia, oxidative stress, extra-physiologic oxygen shock/stress (EPHOSS), endoplasmic reticulum (ER) stress, replicative stress, and stress related to DNA damage. Coping with these stress factors may help reduce the negative effects of cell culture on HSC potential, provide a better understanding of the true impact of certain treatments in the absence of confounding stress factors. This may facilitate the development of better ex vivo expansion protocols of HSCs with long-term engraftment potential without induction of stem cell exhaustion by cellular senescence or loss of cell viability. This review summarizes some of available strategies that may be used to protect HSCs from culture-induced stress conditions.


2021 ◽  
Vol 22 (13) ◽  
pp. 6663
Author(s):  
Maurycy Jankowski ◽  
Mariusz Kaczmarek ◽  
Grzegorz Wąsiatycz ◽  
Claudia Dompe ◽  
Paul Mozdziak ◽  
...  

Next-generation sequencing (RNAseq) analysis of gene expression changes during the long-term in vitro culture and osteogenic differentiation of ASCs remains to be important, as the analysis provides important clues toward employing stem cells as a therapeutic intervention. In this study, the cells were isolated from adipose tissue obtained during routine surgical procedures and subjected to 14-day in vitro culture and differentiation. The mRNA transcript levels were evaluated using the Illumina platform, resulting in the detection of 19,856 gene transcripts. The most differentially expressed genes (fold change >|2|, adjusted p value < 0.05), between day 1, day 14 and differentiated cell cultures were extracted and subjected to bioinformatical analysis based on the R programming language. The results of this study provide molecular insight into the processes that occur during long-term in vitro culture and osteogenic differentiation of ASCs, allowing the re-evaluation of the roles of some genes in MSC progression towards a range of lineages. The results improve the knowledge of the molecular mechanisms associated with long-term in vitro culture and differentiation of ASCs, as well as providing a point of reference for potential in vivo and clinical studies regarding these cells’ application in regenerative medicine.


2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii414-iii414
Author(s):  
Muh-Lii Liang ◽  
Tsung-Han Hsieh ◽  
Tai-Tong Wong

Abstract BACKGROUND Glial-lineage tumors constitute a heterogeneous group of neoplasms, comprising gliomas, oligodendrogliomas, and ependymomas, which account for 40%–50% of all pediatric central nervous system tumors. Advances in modern neuro-oncological therapeutics are aimed at improving neoadjuvant chemotherapy and deferring radiotherapy because radiation exposure may cause long-term side effects on the developing brain in young children. Despite aggressive treatment, more than half the high-grade gliomas (pHGGs) and one-third of ependymomas exhibit recurrence within 2 years of initial treatment. METHODS By using integrated bioinformatics and through experimental validation, we found that at least one gene among CCND1, CDK4, and CDK6 was overexpressed in pHGGs and ependymomas. RESULTS The use of abemaciclib, a highly selective CDK4/6 inhibitor, effectively inhibited cell proliferation and reduced the expression of cell cycle–related and DNA repair–related gene expression, which was determined through RNA-seq analysis. The efficiency of abemaciclib was validated in vitro in pHGGs and ependymoma cells and in vivo by using subcutaneously implanted ependymoma cells from patient-derived xenograft (PDX) in mouse models. Abemaciclib demonstrated the suppression of RB phosphorylation, downstream target genes of E2F, G2M checkpoint, and DNA repair, resulting in tumor suppression. CONCLUSION Abemaciclib showed encouraging results in preclinical pediatric glial-lineage tumors models and represented a potential therapeutic strategy for treating challenging tumors in children.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii88-ii88
Author(s):  
Alison Mercer-Smith ◽  
Wulin Jiang ◽  
Alain Valdivia ◽  
Juli Bago ◽  
Scott Floyd ◽  
...  

Abstract INTRODUCTION Non-small cell lung cancer (NSCLC) is the most common cancer to form brain metastases. Radiation treatment is standard-of-care, but recurrence is still observed in 40% of patients. An adjuvant treatment is desperately needed to track down and kill tumor remnants after radiation. Tumoritropic neural stem cells (NSCs) that can home to and deliver a cytotoxic payload offer potential as such an adjuvant treatment. Here we show the transdifferentiation of human fibroblasts into tumor-homing induced neural stem cells (hiNSCs) that secrete the cytotoxic protein TRAIL (hiNSC-TRAIL) and explore the use of hiNSC-TRAIL to treat NSCLC brain metastases. METHODS To determine the migratory capacity of hiNSCs, hiNSCs were infused intracerebroventricularly (ICV) into mice bearing established bilateral NSCLC H460 brain tumors. hiNSC accumulation at tumor foci was monitored using bioluminescent imaging and post-mortem fluorescent analysis. To determine synergistic effects of radiation with TRAIL on NSCLC, we performed in vitro co-culture assays and isobologram analysis. In vivo, efficacy was determined by tracking the progression and survival of mice bearing intracranial H460 treated with hiNSC-TRAIL alone or in combination with 2 Gy radiation. RESULTS/CONCLUSION Following ICV infusion, hiNSCs persisted in the brain for &gt; 1 week and migrated from the ventricles to colocalize with bilateral tumor foci. In vitro, viability assays and isobologram analysis revealed the combination treatment of hiNSC-TRAIL and 2 Gy radiation induced synergistic killing (combination index=0.64). In vivo, hiNSC-TRAIL/radiation combination therapy reduced tumor volumes &gt; 90% compared to control-treated animals while radiation-only and hiNSC-TRAIL-only treated mice showed 21% and 52% reduced volumes, respectively. Dual-treatment extended survival 40%, increasing survival from a median of 20 days in controls to 28 days in the treatment group. These results suggest hiNSC-TRAIL can improve radiation therapy for NSCLC brain metastases and could potentially improve outcomes for patients suffering from this aggressive form of cancer.


2013 ◽  
Vol 2 (10) ◽  
pp. 731-744 ◽  
Author(s):  
Christopher J. Sontag ◽  
Hal X. Nguyen ◽  
Noriko Kamei ◽  
Nobuko Uchida ◽  
Aileen J. Anderson ◽  
...  

Blood ◽  
2011 ◽  
Vol 117 (18) ◽  
pp. 4773-4777 ◽  
Author(s):  
Hal E. Broxmeyer ◽  
Man-Ryul Lee ◽  
Giao Hangoc ◽  
Scott Cooper ◽  
Nutan Prasain ◽  
...  

Abstract Cryopreservation of hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) is crucial for cord blood (CB) banking and transplantation. We evaluated recovery of functional HPC cryopreserved as mononuclear or unseparated cells for up to 23.5 years compared with prefreeze values of the same CB units. Highly efficient recovery (80%-100%) was apparent for granulocyte-macrophage and multipotential hematopoietic progenitors, although some collections had reproducible low recovery. Proliferative potential, response to multiple cytokines, and replating of HPC colonies was extensive. CD34+ cells isolated from CB cryopreserved for up to 21 years had long-term (≥ 6 month) engrafting capability in primary and secondary immunodeficient mice reflecting recovery of long-term repopulating, self-renewing HSCs. We recovered functionally responsive CD4+ and CD8+ T lymphocytes, generated induced pluripotent stem (iPS) cells with differentiation representing all 3 germ cell lineages in vitro and in vivo, and detected high proliferative endothelial colony forming cells, results of relevance to CB biology and banking.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi29-vi30
Author(s):  
Shreya Budhiraja ◽  
Shivani Baisiwala ◽  
Khizar Nandoliya ◽  
Li Chen ◽  
Crismita Dmello ◽  
...  

Abstract Glioblastoma (GBM) is the most aggressive and common type of adult malignant brain tumor, with a median survival of only 21 months. To identify which genes drive its highly aggressive phenotype, we performed a genome-wide CRISPR-Cas9 knockout screen. Results showed substantial enrichment of ~160 novel essential oncogenic driver genes and pathways, including a previously unstudied gene THOC1—involved in RNA processing—that showed significant elevations in expression at RNA and protein levels (p&lt; 0.05) in GBM, as well as a significant survival benefit in patient datasets when downregulated (p&lt; 0.05). Knocking out THOC1 resulted in cell death in multiple GBM patient-derived xenograft (PDX) lines and extended survival compared to the controls (p&lt; 0.01) in vivo. Overexpression of THOC1 in neural stem cells resulted in transformation to a cancerous phenotype, as evidenced by sphere formation in a soft agar assay (p&lt; 0.01) and in vivo tumor engraftment assays. Further investigation of THOC1 through immunoprecipitation in neural stem cells and multiple GBM lines showed significant interaction in GBM with histone deacetylase complex SIN3A, involved in recruiting major histone deacetylases in order to close the DNA and prevent the accumulation of R-loops, RNA:DNA hybrids that pose a threat to genomic stability. Additional investigation revealed that THOC1-knockdowns in vitro induced R-loop formation and DNA damage, while THOC1-overexpression in vitro resulted in an untenable decrease in R-loops and DNA damage, suggesting that the THOC1-SIN3A axis is elevated in GBM in order to prevent the accumulation of genotoxic R-loops. Additionally, histone deacetylase activity was shown to be elevated in THOC1-overexpression conditions and reduced in THOC1-knockdown conditions, confirming that the THOC1-SIN3A axis functions to prevent R-loop accumulation through the epigenetic regulation. In summary, our whole-genome CRISPR-Cas9 knockout screen has identified a promising therapeutic target for GBM—a disease desperately in need of therapeutic innovations.


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