scholarly journals TMED3/RPS15A Axis promotes the development and progression of osteosarcoma

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wei Xu ◽  
Yifan Li ◽  
Xiaojian Ye ◽  
Yunhan Ji ◽  
Yu Chen ◽  
...  
Keyword(s):  
Biological Function ◽  
Profile Analysis ◽  
Tumor Model ◽  
Underlying Mechanism ◽  
Molecular Therapy ◽  
Loss Of Function ◽  
Osteosarcoma Cells ◽  
Downstream Target

Abstract Background Osteosarcoma is a primary malignant tumor that mainly affects children and young adults. Transmembrane emp24 trafficking protein 3 (TMED3) may be involved in the regulation of malignant cancer behaviors. However, the role of TMED3 in osteosarcoma remains mysterious. In this study, the potential biological function and underlying mechanism of TMED3 in progression of osteosarcoma was elaborated. Methods The expression of TMED3 in osteosarcoma was analyzed by immunohistochemical staining. The biological function of TMED3 in osteosarcoma was determined through loss-of-function assays in vitro. The effect of TMED3 downregulation on osteosarcoma was further explored by xenograft tumor model. The molecular mechanism of the regulation of TMED3 on osteosarcoma was determined by gene expression profile analysis. Results The expression of TMED3 in osteosarcoma tissues was significantly greater than that in matched adjacent normal tissues. Knockdown of TMED3 inhibited the progression of osteosarcoma by suppressing proliferation, impeding migration and enhancing apoptosis in vitro. We further validated that knockdown of TMED3 inhibited osteosarcoma generation in vivo. Additionally, ribosomal protein S15A (RPS15A) was determined as a potential downstream target for TMED3 involved in the progression of osteosarcoma. Further investigations elucidated that the simultaneous knockdown of RPS15A and TMED3 intensified the inhibitory effects on osteosarcoma cells. Importantly, knockdown of RPS15A alleviated the promotion effects of TMED3 overexpression in osteosarcoma cells. Conclusions In summary, these findings emphasized the importance of TMED3/RPS15A axis in promoting tumor progression, which may be a promising candidate for molecular therapy of osteosarcoma.

Genetic evidence for the transcriptional-activating function of Homothorax during adult fly development

Development ◽  
2001 ◽  
Vol 128 (18) ◽  
pp. 3405-3413 ◽  
Author(s):  
Adi Inbal ◽  
Naomi Halachmi ◽  
Charna Dibner ◽  
Dale Frank ◽  
Adi Salzberg
Keyword(s):  
Transcriptional Activity ◽  
Target Genes ◽  
Genetic Evidence ◽  
In Vivo Studies ◽  
Loss Of Function ◽  
Native Form ◽  
Downstream Target ◽  
Activating Function

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.

scholarly journals The cerebral cavernous malformation proteins CCM2L and CCM2 prevent the activation of the MAP kinase MEKK3

2015 ◽  
Vol 112 (46) ◽  
pp. 14284-14289 ◽  
Author(s):  
Xavier Cullere ◽  
Eva Plovie ◽  
Paul M. Bennett ◽  
Calum A. MacRae ◽  
Tanya N. Mayadas
Keyword(s):  
Endothelial Cells ◽  
Cavernous Malformation ◽  
Body Axis ◽  
Cerebral Cavernous Malformations ◽  
Loss Of Function ◽  
Cavernous Malformations ◽  
Downstream Target ◽  
Density Flow

Three genes, CCM1, CCM2, and CCM3, interact genetically and biochemically and are mutated in cerebral cavernous malformations (CCM). A recently described member of this CCM family of proteins, CCM2-like (CCM2L), has high homology to CCM2. Here we show that its relative expression in different tissues differs from that of CCM2 and, unlike CCM2, the expression of CCM2L in endothelial cells is regulated by density, flow, and statins. In vitro, both CCM2L and CCM2 bind MEKK3 in a complex with CCM1. Both CCM2L and CCM2 interfere with MEKK3 activation and its ability to phosphorylate MEK5, a downstream target. The in vivo relevance of this regulation was investigated in zebrafish. A knockdown of ccm2l and ccm2 in zebrafish leads to a more severe “big heart” and circulation defects compared with loss of function of ccm2 alone, and also leads to substantial body axis abnormalities. Silencing of mekk3 rescues the big heart and body axis phenotype, suggesting cross-talk between the CCM proteins and MEKK3 in vivo. In endothelial cells, CCM2 deletion leads to activation of ERK5 and a transcriptional program that are downstream of MEKK3. These findings suggest that CCM2L and CCM2 cooperate to regulate the activity of MEKK3.

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 Novel Long Noncoding RNA 005620 Induces Epirubicin Resistance in Triple-Negative Breast Cancer by Regulating ITGB1 Expression

2021 ◽  
Vol 11 ◽  
Author(s):  
Fengliang Wang ◽  
Sujin Yang ◽  
Mingming Lv ◽  
Fei Chen ◽  
Hong Yin ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Triple Negative Breast Cancer ◽  
Noncoding Rna ◽  
Triple Negative ◽  
Sequencing Analysis ◽  
Loss Of Function ◽  
Integrin Β1 ◽  
Downstream Target

Triple-negative breast cancer (TNBC) is often treated with anthracyclines (e.g., epirubicin or doxorubicin), but very little is known about anthracycline resistance, especially epirubicin resistance in TNBC. To identify novel long noncoding RNAs (lncRNAs) involved in epirubicin resistance in TNBC, we established a new TNBC MDA-MB-231 cell line that was resistant to epirubicin (Epi-R). A total of 12 differentially expressed lncRNAs were identified using RNA sequencing analysis of Epi-R cells. Among these lncRNAs, we found a novel intronic lncRNA, lnc005620, was highly expressed in Epi-R cells and human TNBC tissues. Further gain- and loss-of-function studies demonstrated that lnc005620 played an oncogenic role and partially abrogated the effects of epirubicin on TNBC cells. Using iTRAQ proteomics analysis, we found that three members of the integrin family, integrin β4, integrin β1 and integrin α6, were all upregulated in Epi-R MDA-MB-231 cells. Integrin β1, encoded by the ITGB1 gene, was validated to be a downstream target of lnc005620 in Epi-R MDA-MB-231 cells. Our study demonstrates that novel lnc005620 promotes TNBC progression and chemoresistance to epirubicin via integrin β1 both in vitro and in vivo and provides a promising therapeutic target for TNBC patients in terms of enhancing the benefits of epirubicin treatment.

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.

scholarly journals Novel insights into stress-induced susceptibility to influenza: corticosterone impacts interferon-β responses by Mfn2-mediated ubiquitin degradation of MAVS

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Zhuo Luo ◽  
Li-Fang Liu ◽  
Ying-Nan Jiang ◽  
Lu-Ping Tang ◽  
Wen Li ◽  
...  
Keyword(s):  
Influenza Infection ◽  
Mrna Level ◽  
Underlying Mechanism ◽  
Fine Tuning ◽  
Loss Of Function ◽  
Mitofusin 2 ◽  
Viral Susceptibility ◽  
Mitochondrial Antiviral Signaling

Abstract Although stress has been known to increase the susceptibility of pathogen infection, the underlying mechanism remains elusive. In this study, we reported that restraint stress dramatically enhanced the morbidity and mortality of mice infected with the influenza virus (H1N1) and obviously aggravated lung inflammation. Corticosterone (CORT), a main type of glucocorticoids in rodents, was secreted in the plasma of stressed mice. We further found that this stress hormone significantly boosted virus replication by restricting mitochondrial antiviral signaling (MAVS) protein-transduced IFN-β production without affecting its mRNA level, while the deficiency of MAVS abrogated stress/CORT-induced viral susceptibility in mice. Mechanistically, the effect of CORT was mediated by proteasome-dependent degradation of MAVS, thereby resulting in the impediment of MAVS-transduced IFN-β generation in vivo and in vitro. Furthermore, RNA-seq assay results indicated the involvement of Mitofusin 2 (Mfn2) in this process. Gain- and loss-of-function experiments indicated that Mfn2 interacted with MAVS and recruited E3 ligase SYVN1 to promote the polyubiquitination of MAVS. Co-immunoprecipitation experiments clarified an interaction between any two regions of Mfn2 (HR1), MAVS (C-terminal/TM) and SYVN1 (TM). Collectively, our findings define the Mfn2-SYVN1 axis as a new signaling cascade for proteasome-dependent degradation of MAVS and a ‘fine tuning’ of antiviral innate immunity in response to influenza infection under stress.

Pelle kinase is activated by autophosphorylation during Toll signaling in Drosophila

Development ◽  
2002 ◽  
Vol 129 (8) ◽  
pp. 1925-1933 ◽  
Author(s):  
Baohe Shen ◽  
James L. Manley
Keyword(s):  
Dependent Manner ◽  
Loss Of Function ◽  
Concentration Dependent Manner ◽  
Downstream Target ◽  
Toll Signaling ◽  
Early Embryos ◽  
High Concentrations ◽  
L2 Cells

The Drosophila Pelle kinase plays a key role in the evolutionarily conserved Toll signaling pathway, but the mechanism responsible for its activation has been unknown. We present in vivo and in vitro evidence establishing an important role for concentration-dependent autophosphorylation in the signaling process. We first show that Pelle phosphorylation can be detected transiently in early embryos, concomitant with activation of signaling. Importantly, Pelle phosphorylation is enhanced in a gain-of-function Toll mutant (Toll10b), but decreased by loss-of-function Toll alleles. Next we found that Pelle is phosphorylated in transfected Schneider L2 cells in a concentration-dependent manner such that significant modification is observed only at high Pelle concentrations, which coincide with levels required for phosphorylation and activation of the downstream target, Dorsal. Pelle phosphorylation is also enhanced in L2 cells co-expressing Toll10b, and is dependent on Pelle kinase activity. In vitro kinase assays revealed that recombinant, autophosphorylated Pelle is far more active than unphosphorylated Pelle. Importantly, unphosphorylated Pelle becomes autophosphorylated, and activated, by incubation at high concentrations. We discuss these results in the context of Toll-like receptor mediated signaling in both flies and mammals.

scholarly journals FSMP-09. FORMATE PROMOTES CANCER CELL INVASION AND METASTASIS VIA CALCIUM SIGNALING

2020 ◽  
Vol 3 (Supplement_1) ◽  
pp. i18-i18
Author(s):  
Catherine Delbrouck ◽  
Vitaly I Pozdeev ◽  
Anais Oudin ◽  
Kamil Grzyb ◽  
Laura Neises ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Ex Vivo ◽  
Tumor Model ◽  
Underlying Mechanism ◽  
Tumor Escape ◽  
Proliferating Cells ◽  
Nucleotide Synthesis ◽  
Formate Production

Abstract Serine catabolism via the folate cycle provides formate that is essential for nucleotide synthesis in proliferating cells. In addition to this canonical function to support biomass production in anabolic cells, we have recently demonstrated in vitro and in vivo that formate production in cancer cells is often in excess of the anabolic demand. This excess formate production is characterized by formate overflow and thus, net formate excretion into the tumor microenvironment. Interestingly, we observe increased rates of formate overflow upon different chemical perturbations that induce growth arrest. Thus, stressed cancer cells that encounter growth restriction such as upon chemotherapy, are often characterized by increased formate release rates. We demonstrated that such high formate levels in the extracellular space promote invasion of glioblastoma cells. Using ex vivo brain slice cultures and an orthotopic brain tumor model, we demonstrate that silencing MTHFD1L, the essential enzyme to enable formate overflow, results in decreased invasiveness of the tumor. Embarking from this observation, we investigated the underlying mechanism and now provide evidence that the formate-dependent increase of cell motility is mediated by an activation of Ca2+ signaling. Activation of Ca2+ signaling triggers integrin and matrix metallopeptidase (MMP) responses enabling the invasion process. Targeting either the Ca2+ response or MMP release can suppress the formate dependent increase in invasion. Finally, we tested the effect of formate also in context of breast cancer where we were able to recapitulate our observation of increased invasiveness and, in this case, formate also promoted the metastatic potential. We conclude that excreted formate might serve as a cellular stress signal that represents a promotive trigger to support tumor escape mechanisms.

scholarly journals MiR-22 Inhibition Alleviates Cardiac Dysfunction in Doxorubicin-Induced Cardiomyopathy by Targeting the sirt1/PGC-1α Pathway

2021 ◽  
Vol 12 ◽  
Author(s):  
Runze Wang ◽  
Yuerong Xu ◽  
Xiaolin Niu ◽  
Yexian Fang ◽  
Dong Guo ◽  
...  
Keyword(s):  
Cardiac Dysfunction ◽  
Poor Prognosis ◽  
Cardiac Fibrosis ◽  
Underlying Mechanism ◽  
Protective Effects ◽  
Loss Of Function ◽  
Life Threatening

Doxorubicin (DOX) cardiotoxicity is a life-threatening side effect that leads to a poor prognosis in patients receiving chemotherapy. We investigated the role of miR-22 in doxorubicin-induced cardiomyopathy and the underlying mechanism in vivo and in vitro. Specifically, we designed loss-of-function and gain-of-function experiments to identify the role of miR-22 in doxorubicin-induced cardiomyopathy. Our data suggested that inhibiting miR-22 alleviated cardiac fibrosis and cardiac dysfunction induced by doxorubicin. In addition, inhibiting miR-22 mitigated mitochondrial dysfunction through the sirt1/PGC-1α pathway. Knocking out miR-22 enhanced mitochondrial biogenesis, as evidenced by increased PGC-1α, TFAM, and NRF-1 expression in vivo. Furthermore, knocking out miR-22 rescued mitophagy, which was confirmed by increased expression of PINK1 and parkin and by the colocalization of LC3 and mitochondria. These protective effects were abolished by overexpressing miR-22. In conclusion, miR-22 may represent a new target to alleviate cardiac dysfunction in doxorubicin-induced cardiomyopathy and improve prognosis in patients receiving chemotherapy.

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.

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