scholarly journals Overcoming cisplatin resistance in osteosarcoma through the miR-199a-modulated inhibition of HIF-1α

2019 ◽  
Vol 39 (11) ◽  
Author(s):  
Ajimu Keremu ◽  
Abudureyimu Aini ◽  
Yusufuaji Maimaitirexiati ◽  
Zhilin Liang ◽  
Pazila Aila ◽  
...  
Keyword(s):  
Target Genes ◽  
Cisplatin Resistance ◽  
Tumour Progression ◽  
Osteosarcoma Cell ◽  
Osteosarcoma Cells ◽  
Direct Target ◽  
Low Levels ◽  
Resistant Cells

Abstract Dysregulation of miRNAs has been shown to contribute to multiple tumorigenic processes, as well as to correlate with tumour progression and prognosis. miR-199a has been shown to be dysregulated in multiple tumour types. However, the association between miR-199a and the chemoresistance features of osteosarcoma are not well understood, the target genes for miR-199a and the regulatory mechanisms are also unknown. In the present study, we demonstrated that miR-199a is expressed at low levels in osteosarcoma cells and patient samples. By the selection and establishment of cisplatin resistant osteosarcoma cell line, we observed a correlation between miR-199a and cisplatin resistance in osteosarcoma cells: resistant cells exhibit attenuated miR-199a expressions and exogenous overexpression of miR-199a sensitizes osteosarcoma cells to cisplatin. Moreover, we identified HIF-1α as a direct target for miR-199a. Intriguingly, cisplatin resistant osteosarcoma cells display significantly elevated HIF-1α expression under hypoxia. We report here overexpression of miR-199a resensitizes cisplatin resistant cells to cisplatin through inhibition of HIF-1α in vitro and in vivo. Finally, by analysing the clinical osteosarcoma patient samples, we demonstrate a reverse correlation between miR-199a and HIF-1α mRNAs. Our study will provide mechanisms for the miRNA-mediated anticancer therapy and miR-199a may be considered a promising therapeutic agent for osteosarcoma patients who fail to respond to conventional chemotherapy.

scholarly journals LncRNA SNHG15 contributes to doxorubicin resistance of osteosarcoma cells through targeting the miR-381-3p/GFRA1 axis

2020 ◽  
Vol 15 (1) ◽  
pp. 871-883
Author(s):  
Jinshan Zhang ◽  
Dan Rao ◽  
Haibo Ma ◽  
Defeng Kong ◽  
Xiaoming Xu ◽  
...  
Keyword(s):  
Cell Lines ◽  
Noncoding Rna ◽  
Xenograft Model ◽  
Inhibitory Effect ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Osteosarcoma Cell ◽  
Osteosarcoma Cells

AbstractBackgroundOsteosarcoma is a common primary malignant bone cancer. Long noncoding RNA small nucleolar RNA host gene 15 (SNHG15) has been reported to play an oncogenic role in many cancers. Nevertheless, the role of SNHG15 in the doxorubicin (DXR) resistance of osteosarcoma cells has not been fully addressed.MethodsCell Counting Kit-8 assay was conducted to measure the half-maximal inhibitory concentration value of DXR in osteosarcoma cells. Western blotting was carried out to examine the levels of autophagy-related proteins and GDNF family receptor alpha-1 (GFRA1). Quantitative reverse transcription-polymerase chain reaction was performed to determine the levels of SNHG15, miR-381-3p, and GFRA1. The proliferation of osteosarcoma cells was measured by MTT assay. The binding sites between miR-381-3p and SNHG15 or GFRA1 were predicted by Starbase bioinformatics software, and the interaction was confirmed by dual-luciferase reporter assay. Murine xenograft model was established to validate the function of SNHG15 in vivo.ResultsAutophagy inhibitor 3-methyladenine sensitized DXR-resistant osteosarcoma cell lines to DXR. SNHG15 was upregulated in DXR-resistant osteosarcoma tissues and cell lines. SNHG15 knockdown inhibited the proliferation, DXR resistance, and autophagy of osteosarcoma cells. MiR-381-3p was a direct target of SNHG15, and GFRA1 bound to miR-381-3p in osteosarcoma cells. SNHG15 contributed to DXR resistance through the miR-381-3p/GFRA1 axis in vitro. SNHG15 depletion contributed to the inhibitory effect of DXR on osteosarcoma tumor growth through the miR-381-3p/GFRA1 axis in vivo.ConclusionsSNHG15 enhanced the DXR resistance of osteosarcoma cells through elevating the autophagy via targeting the miR-381-3p/GFRA1 axis. Restoration of miR-381-3p expression might be an underlying therapeutic strategy to overcome the DXR resistance of osteosarcoma.

scholarly journals Tumor Suppressor Function of miR-127-3p and miR-376a-3p in Osteosarcoma Cells

Cancers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2019 ◽  
Author(s):  
Joerg Fellenberg ◽  
Burkhard Lehner ◽  
Heiner Saehr ◽  
Astrid Schenker ◽  
Pierre Kunz
Keyword(s):  
Tumor Suppressor ◽  
Therapeutic Strategies ◽  
High Dose ◽  
Osteosarcoma Cell ◽  
Tumor Suppressor Function ◽  
Osteosarcoma Cells ◽  
Aberrant Expression ◽  
Suppressor Function

Since the introduction of high-dose chemotherapy about 35 years ago, survival rates of osteosarcoma patients have not been significantly improved. New therapeutic strategies replacing or complementing conventional chemotherapy are therefore urgently required. MicroRNAs represent promising targets for such new therapies, as they are involved in the pathology of multiple types of cancer, and aberrant expression of several miRNAs has already been shown in osteosarcoma. In this study, we identified silencing of miR-127-3p and miR-376a-3p in osteosarcoma cell lines and tissues and investigated their role as potential tumor suppressors in vitro and in vivo. Transfection of osteosarcoma cells (n = 6) with miR-127-3p and miR-376a-3p mimics significantly inhibited proliferation and reduced the colony formation capacity of these cells. In contrast, we could not detect any influence of miRNA restoration on cell cycle and apoptosis induction. The effects of candidate miRNA restoration on tumor engraftment and growth in vivo were analyzed using a chicken chorioallantoic membrane (CAM) assay. Cells transfected with mir-127-3p and miR-376a-3p showed reduced tumor take rates and tumor volumes and a significant decrease of the cumulative tumor volumes to 41% and 54% compared to wildtype cells. The observed tumor suppressor function of both analyzed miRNAs indicates these miRNAs as potentially valuable targets for the development of new therapeutic strategies for the treatment of osteosarcoma.

scholarly journals Ets-dependent Regulation of Target Gene Expression during Megakaryopoiesis

2004 ◽  
Vol 279 (50) ◽  
pp. 52183-52190 ◽  
Author(s):  
Pascale Jackers ◽  
Gabor Szalai ◽  
Omar Moussa ◽  
Dennis K. Watson
Keyword(s):  
Transcription Factors ◽  
Rna Polymerase Ii ◽  
Chromatin Immunoprecipitation ◽  
Target Genes ◽  
Hematopoietic Stem ◽  
Exogenous Expression ◽  
Direct Target ◽  
Transcriptional Complex

Megakaryopoiesis is the process by which hematopoietic stem cells in the bone marrow differentiate into mature megakaryocytes. The expression of megakaryocytic genes during megakaryopoiesis is controlled by specific transcription factors. Fli-1 and GATA-1 transcription factors are required for development of megakaryocytes and promoter analysis has definedin vitrofunctional binding sites for these factors in several megakaryocytic genes, includingGPIIb,GPIX, andC-MPL. Herein, we utilize chromatin immunoprecipitation to examine the presence of Ets-1, Fli-1, and GATA-1 on these promotersin vivo. Fli-1 and Ets-1 occupy the promoters ofGPIIb,GPIX, andC-MPLgenes in both Meg-01 and CMK11-5 cells. WhereasGPIIbis expressed in both Meg-01 and CMK11-5 cells,GPIXandC-MPLare only expressed in the more differentiated CMK11–5 cells. Thus,in vivooccupancy by an Ets factor is not sufficient to promote transcription of some megakaryocytic genes. GATA-1 and Fli-1 are both expressed in CMK11-5 cells and co-occupy theGPIXandC-MPLpromoters. Transcription of all three megakaryocytic genes is correlated with the presence of acetylated histone H3 and phosphorylated RNA polymerase II on their promoters. We also show that exogenous expression of GATA-1 in Meg-01 cells leads to the expression of endogenous c-mpl and gpIX mRNA. WhereasGPIIb,GPIX, andC-MPLare direct target genes for Fli-1, both Fli-1 and GATA-1 are required for formation of an active transcriptional complex on theC-MPLandGPIXpromotersin vivo. In contrast,GPIIbexpression appears to be independent of GATA-1 in Meg-01 cells.

scholarly journals Armadillo Repeat-Containing Protein 8 (ARMC8) Silencing Inhibits Proliferation and Invasion in Osteosarcoma Cells

2016 ◽  
Vol 24 (5) ◽  
pp. 381-389 ◽  
Author(s):  
Feng Jiang ◽  
Yan Shi ◽  
Hong Lu ◽  
Guojun Li
Keyword(s):  
Epithelial Mesenchymal Transition ◽  
Underlying Mechanism ◽  
Migration And Invasion ◽  
Osteosarcoma Cell ◽  
Osteosarcoma Cells ◽  
Mesenchymal Transition ◽  
Armadillo Repeat ◽  
Proliferation And Invasion

Armadillo repeat-containing protein 8 (ARMC8) plays an important role in regulating cell migration, proliferation, tissue maintenance, signal transduction, and tumorigenesis. However, the expression pattern and role of ARMC8 in osteosarcoma are still unclear. In this study, our aims were to examine the effects of ARMC8 on osteosarcoma and to explore its underlying mechanism. Our results demonstrated that ARMC8 was overexpressed in osteosarcoma cell lines. Knockdown of ARMC8 significantly inhibited osteosarcoma cell proliferation in vitro and markedly inhibited xenograft tumor growth in vivo. ARMC8 silencing also suppressed the epithelial‐mesenchymal transition (EMT) phenotype, as well as inhibited the migration and invasion of osteosarcoma cells. Furthermore, knockdown of ARMC8 obviously inhibited the expression of β-catenin, c-Myc, and cyclin D1 in MG-63 cells. In conclusion, this report demonstrates that ARMC8 silencing inhibits proliferation and invasion of osteosarcoma cells. Therefore, ARMC8 may play an important role in the development and progression of human osteosarcoma and may represent a novel therapeutic target in the treatment of osteosarcoma.

scholarly journals Exosomal miR-199a-5p Inhibits Tumorigenesis and Angiogenesis by Targeting VEGFA in Osteosarcoma

2021 ◽  
Author(s):  
Lu Zhang ◽  
Hongxin Cao ◽  
Guanghui Gu ◽  
Dehui Hou ◽  
Yunhao You ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Target Genes ◽  
Enrichment Analysis ◽  
Luciferase Reporter ◽  
Pathway Enrichment Analysis ◽  
Osteosarcoma Cell ◽  
Plasma Samples ◽  
Osteosarcoma Cells ◽  
Hub Genes

Abstract Background: Osteosarcoma (OS) is the most common primary bone malignancy in children and adolescents. microRNAs have been found to play a vital role in tumor angiogenesis. Here, we investigated the effects of miR-199a-5p on tumor growth and angiogenesis in osteosarcoma. Furthermore, the underlying molecular mechanisms and signaling pathways were explored.Methods: The datasets were extracted from the Gene Expression Omnibus and the differentially expressed miRNAs (DEmiRNAs) were screened out by the GEO2R online platform. The potential target genes were predicted using the miRTarBase database. The predicted target genes were further analyzed by Gene Ontology and pathway enrichment analysis and a regulatory network of DEmiRNAs and their target genes was constructed. In addition, the effects of osteosarcoma cell derived exosomal miR-199a-5p on the proliferation, migration and neovascularization of HUVECs were evaluated by conducting EdU assays, Transwell experiments and tube formation assays. A dual-luciferase reporter assay was performed to detect whether VEGFA was the direct target of miR-199a-5p. Furthermore, in vivo xenograft models were established to further investigate the intrinsic role of miR-199a-5p in osteosarcoma tumorigenesis and angiogenesis. Results: A total of 149 DE-miRNAs were screened out, including 136 upregulated miRNAs and 13 downregulated miRNAs in human osteosarcoma plasma samples compared with normal plasma samples. A total of 1313 target genes of the top three upregulated and downregulated miRNAs were predicted. In the PPI network, the top 10 hub nodes with higher degrees were identified as hub genes, such as TP53 and VEGFA. By constructing the miRNA-hub gene network, we found that most of hub genes could be potentially modulated by miR-663a, miR-199a-5p and miR-223-3p. In addition, we found that the expression level of miR-199a-5p in exosomes derived from osteosarcoma cells was remarkably higher than the osteosarcoma cells, and the exosomes derived from osteosarcoma cells were transported to HUVECs. Overexpression of miR-199a-5p could significantly inhibited HUVEC proliferation, migration and neovascularization, whereas downregulation of miR-199a-5p expression exerted the opposite effect. Moreover, the in vivo results verified that overexpression of miR-199a-5p in osteosarcoma cells could suppress the growth and angiogenesis of tumors. Conclusion: Our results demonstrated that miR-199a-5p could be transported from osteosarcoma cells to HUVECs through exosomes, subsequently targeting VEGFA and inhibiting the growth and angiogenesis of osteosarcoma. Therefore, miR-199a-5p may act as a biomarker in the diagnosis and treatment of osteosarcoma.

scholarly journals Degradation of long non-coding RNA-CIR decelerates proliferation, invasion and migration, but promotes apoptosis of osteosarcoma cells

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Shiwei Liu ◽  
Jingchao Li ◽  
Liang Kang ◽  
Yueyang Tian ◽  
Yuan Xue
Keyword(s):  
Tumor Growth ◽  
Osteosarcoma Cell ◽  
Loss Of Function ◽  
Osteosarcoma Cells ◽  
Invasion And Migration ◽  
Normal Tissues ◽  
Novel Target ◽  
And Migration

Abstract Background Over the years, long non-coding RNAs (lncRNAs) have been clarified in malignancies, this research was focused on the role of lncRNA cartilage injury-related (lncRNA-CIR) in osteosarcoma cells. Methods LncRNA-CIR expression in osteosarcoma tissues and cells, and adjacent normal tissues and normal osteoblasts was determined, then the relations between lncRNA-CIR expression and the clinicopathological features, and between lncRNA-CIR expression and the prognosis of osteosarcoma patients were analyzed. Moreover, the MG63 and 143B cells were treated with silenced or overexpressed lncRNA-CIR, and then the proliferation, invasion, migration and apoptosis of the cells were evaluated by gain- and loss-of-function approaches. The tumor growth, and proliferation and apoptosis of osteosarcoma cells in vivo were observed by subcutaneous tumorigenesis in nude mice. Results We have found that lncRNA-CIR was up-regulated in osteosarcoma tissues and cells, which was respectively relative to adjacent normal tissues and normal osteoblasts. The expression of lncRNA-CIR was evidently correlated with disease stages, distant metastasis and differentiation of osteosarcoma patients, and the high expression of lncRNA-CIR indicated a poor prognosis. Furthermore, the reduction of lncRNA-CIR could restrict proliferation, invasion and migration, but promote apoptosis of osteosarcoma cells in vitro. Meanwhile, inhibited lncRNA-CIR also restrained tumor growth and osteosarcoma cell proliferation, whereas accelerated apoptosis of osteosarcoma cells in vivo. Conclusion We have found in this study that the inhibited lncRNA-CIR could decelerate proliferation, invasion and migration, but accelerate apoptosis of osteosarcoma cells, which may provide a novel target for osteosarcoma treatment.

beta3-tubulin is directly repressed by the engrailed protein in Drosophila

Development ◽  
1997 ◽  
Vol 124 (13) ◽  
pp. 2527-2536 ◽  
Author(s):  
N. Serrano ◽  
H.W. Brock ◽  
F. Maschat
Keyword(s):  
Transcription Factor ◽  
Binding Sites ◽  
Transgenic Line ◽  
Target Genes ◽  
Regulatory Protein ◽  
Polytene Chromosomes ◽  
First Intron ◽  
Direct Target

In Drosophila, Engrailed is a nuclear regulatory protein with essential roles during embryonic development. Although Engrailed is a transcription factor, little progress has been achieved in identifying its target genes. We report here the identification of an effector gene, the beta3-tubulin gene, as a direct target of Engrailed. The cytological location of beta3-tubulin, 60C, is a strong site of Engrailed binding on polytene chromosomes. Immunostaining analysis of a transgenic line containing a P[beta3-tubulin-lacZ] construct shows an additional site of Engrailed binding at the location of the transgene. Molecular analysis allowed identification of several Engrailed binding sites, both in vitro and in vivo, within the first intron of the beta3-tubulin locus. Engrailed binding sites identified in vitro are active in larvae. Furthermore, expression of beta3-tubulin is derepressed in the ectoderm of engrailed mutant embryos. Repression of beta3-tubulin by Engrailed is also obtained when Engrailed is ectopically expressed in embryonic mesoderm. Finally, two different sets of Engrailed binding sites are shown to be involved in the early and late regulation of beta3-tubulin by Engrailed during embryogenesis.

scholarly journals Inhibitory Effects of Targeted Regulatory LKB1 Gene on the Proliferation and Invasion of Osteosarcoma Cells

2021 ◽  
Vol 21 (01) ◽  
Author(s):  
Jie Liu
Keyword(s):  
Transcription Factor ◽  
Xenograft Model ◽  
Mtor Inhibitors ◽  
Regulatory Genes ◽  
Osteosarcoma Cell ◽  
Osteosarcoma Cells ◽  
Inhibitory Effects ◽  
Proliferation And Invasion

In this study, Immunodeficiency Nude Mouse Osteosarcoma Xenograft Model was subjected to the drug intervention to explore the effect of bexarotene on the proliferation and invasion of osteosarcoma cell lines in vitro. The inhibitory effects of targeted regulatory genes on the proliferation and invasion of osteosarcoma cells were studied through various in vitro experiments include bioinformatics combined with tissue microarray research, transcription factor prediction combined with co-expression analysis to predict the transcription factor of targeted regulatory genes in osteosarcoma. The RXR protein family, LKB1, AMPK pathway, and mTOR are closely related to the body’s immune regulation. The oral administration of Bexarotene could inhibit the proliferation and able to up-regulate the expression of LKB1 gene in living osteosarcoma tissue. The xenograft model of immunodeficiency nude mice used in this study was reason for reduced the potential immunoregulatory effect of drug targeted LKB1 therapy to a certain extent. However, overexpression of LKB1 in vivo, and combined immunotherapy may become an important immunotherapy approach for osteosarcoma. LKB1 targeted therapy can potentially be used as one of the alternative treatments for mTOR inhibitors.

scholarly journals miR-422a inhibits osteosarcoma proliferation by targeting BCL2L2 and KRAS

2018 ◽  
Vol 38 (2) ◽  
Author(s):  
Hao Zhang ◽  
Qian-Yun He ◽  
Guang-Chao Wang ◽  
Da-Ke Tong ◽  
Ren-Kai Wang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Underlying Mechanism ◽  
Clinical Samples ◽  
Osteosarcoma Cell ◽  
Osteosarcoma Cells ◽  
Induce Cell Cycle Arrest ◽  
Cycle Arrest

Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. However, the underlying mechanism of osteosarcoma carcinogenesis and progression remains unknown. In the present study, we evaluated the expression profile of miRNAs in osteosarcoma tissues and the adjacent normal tissues. We found that the expression of miR-422a was down-regulated in osteosarcoma tissues and cell lines. In addition, we observed significantly elevated levels of repressive H3K9me3 and H3K27me3 and decreased active H3K4me3 on the promote region of miR-422a in osteosarcoma cells and clinical samples. Furthermore, up-regulation of miR-422a exhibited both in vitro and in vivo anti-tumor effects by inhibiting osteosarcoma cell growth and inducing apoptosis and cell cycle arrest. We also found that miR-422a targeted BCL2L2 and KRAS and negatively regulated their protein expression. Furthermore, restoration of miR-422a and knockdown of BCL2L2 and KRAS promoted apoptosis and induce cell cycle arrest in osteosarcoma cells. Taken together, the present study demonstrates that miR-422a may serve as a tumor suppressor in osteosarcoma via inhibiting BCL2L2 and KRAS translation both in vitro and in vivo. Therefore, miR-422a could be developed as a novel therapeutic target in osteosarcoma.

scholarly journals Hsa_circ_0002483 inhibited the progression and enhanced the Taxol sensitivity of non-small cell lung cancer by targeting miR-182-5p

2019 ◽  
Vol 10 (12) ◽  
Author(s):  
Xiaoping Li ◽  
Bo Yang ◽  
Haixia Ren ◽  
Ting Xiao ◽  
Liang Zhang ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Target Genes ◽  
Small Cell ◽  
Small Cell Lung ◽  
Functional Assays ◽  
Taxol Resistance ◽  
Low Levels ◽  
Proliferation And Invasion

AbstractIn this study, we identified a novel circRNA, circ_0002483, and further investigated its functions in the progression and Taxol resistance of NSCLC. We found that circ_0002483 was expressed at low levels in NSCLC tissues and cell lines. Functional assays indicated that circ_0002483 overexpression significantly inhibited NSCLC cell proliferation and invasion in vitro and in vivo and enhanced the sensitivity of NSCLC cells to Taxol. Mechanistically, circ_0002483 was identified to sponge multiple miRNAs including miR-182-5p (also named miR-182), miR-520q-3p, miR-582-3p, miR-587, and miR-655. In addition, circ_0002483 was also demonstrated to regulate the expression of GRB2, FOXO1, and FOXO3, three target genes of miR-182-5p, by sponging miR-182-5p. Circ_0002483 was demonstrated to inhibit NSCLC progression in vitro and in vivo and enhanced the sensitivity of NSCLC cells to Taxol by sponging miR-182-5p to release the inhibition on GRB2, FOXO1, and FOXO3 mRNAs.

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