Osteo-Oto-Hepato-Enteric Syndrome (O2HE) is caused by loss of function mutations in UNC45A

AbstractDespite the rapid discovery of genes for rare genetic disorders, we continue to encounter individuals presenting with hitherto unknown syndromic manifestations. Here, we have studied four affected people in three families presenting with cholestasis, congenital diarrhea, impaired hearing and bone fragility, a clinical entity we have termed O2HE (Osteo-Oto-Hepato-enteric) syndrome. Whole exome sequencing of all affected individuals and their parents identified biallelic mutations in Unc-45 Myosin Chaperone A (UNC45A), as a likely driver for this disorder. Subsequent in vitro and in vivo functional studies of the candidate gene indicated a loss of function paradigm, wherein mutations attenuated or abolished protein activity with concomitant defects in gut development and function.

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Twenty Years of Ferroportin Disease: A Review or An Update of Published Clinical, Biochemical, Molecular, and Functional Features

Pharmaceuticals ◽

10.3390/ph12030132 ◽

2019 ◽

Vol 12 (3) ◽

pp. 132 ◽

Cited By ~ 6

Author(s):

L. Tom Vlasveld ◽

Roel Janssen ◽

Edouard Bardou-Jacquet ◽

Hanka Venselaar ◽

Houda Hamdi-Roze ◽

...

Keyword(s):

Prediction Models ◽

Hereditary Hemochromatosis ◽

Transferrin Saturation ◽

Clinical Analysis ◽

Loss Of Function ◽

Functional Studies ◽

Functional Features ◽

Reported Data

Iron overloading disorders linked to mutations in ferroportin have diverse phenotypes in vivo, and the effects of mutations on ferroportin in vitro range from loss of function (LOF) to gain of function (GOF) with hepcidin resistance. We reviewed 359 patients with 60 ferroportin variants. Overall, macrophage iron overload and low/normal transferrin saturation (TSAT) segregated with mutations that caused LOF, while GOF mutations were linked to high TSAT and parenchymal iron accumulation. However, the pathogenicity of individual variants is difficult to establish due to the lack of sufficiently reported data, large inter-assay variability of functional studies, and the uncertainty associated with the performance of available in silico prediction models. Since the phenotypes of hepcidin-resistant GOF variants are indistinguishable from the other types of hereditary hemochromatosis (HH), these variants may be categorized as ferroportin-associated HH, while the entity ferroportin disease may be confined to patients with LOF variants. To further improve the management of ferroportin disease, we advocate for a global registry, with standardized clinical analysis and validation of the functional tests preferably performed in human-derived enterocytic and macrophagic cell lines. Moreover, studies are warranted to unravel the definite structure of ferroportin and the indispensable residues that are essential for functionality.

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NPR3 inhibits EMT and Tumour Metastasis of Human Osteosarcoma by Activating AKT/mTOR-mediated Autophagy

10.21203/rs.3.rs-923877/v1 ◽

2021 ◽

Author(s):

Zhihong Yao ◽

Yihao Yang ◽

Jiaxiang Chen ◽

Ting Chen ◽

Lei Han ◽

...

Keyword(s):

Molecular Mechanisms ◽

Therapeutic Potential ◽

Loss Of Function ◽

Over Expression ◽

Functional Studies ◽

Qrt Pcr ◽

Tumour Metastasis ◽

Lower Expression

Abstract BackgroundOsteosarcoma is an aggressive primary malignant cancer of bone mainly occurring in adolescence with a characteristic of high metastasis and relapse rate. In our previous study, we first identified that NPR3 was significantly decreased in OS samples. Here, we purposed to investigate the effect and the possible mechanisms of NPR3 on the progression of human OS. MethodsThe expression of NPR3 in OS patients and cells was detected by qRT-PCR, and IHC analysis. The effect of the expression of NPR3 on tumour metastasis was examined in vitro and in vivo. The molecular mechanisms of the regulation of NPR3 were evaluated in vitro and in vivo. The clinical relevance of 5-year overall survival with the expression of NPR3 was evaluated in 294 patients with OS. ResultsFirstly, we indicated that NPR3 was substantially downregulated expression in OS tissues and cells by qRT-PCR and IHC assay. And the patients with lower expression of NPR3 have a poor prognosis. Functional studies revealed that over-expression of NPR3 inhibited the proliferation and invasion of cells. Meanwhile, over-expression of NPR3 markedly inhibited tumorigenesis and weakened tumour metastasis in vivo. Interestingly, we found that over-expression of NPR3 could induce autophagy, promote apoptosis and inhibit EMT. Additionally, overexpression of NPR3 decreased the phosphorylation levels of AKT and mTOR. Loss-of-function experiments displayed that effects of NPR3 were weakened by treatment with the specific autophagy inhibitor Baf-A1 and CQ. ConclusionsTaken together, these results demonstrated that down-regulation of NPR3 promote lung metastasis of human OS by promoting EMT in part through the AKT/mTOR mediated autophagy, suggesting that NPR3 has therapeutic potential for OS patients with metastasis.

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TRIM27 interacts with Iκbα to promote the growth of human renal cancer cells through regulating the NF-κB pathway

BMC Cancer ◽

10.1186/s12885-021-08562-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Chengwu Xiao ◽

Wei Zhang ◽

Meimian Hua ◽

Huan Chen ◽

Bin Yang ◽

...

Keyword(s):

Cell Lines ◽

Prognostic Indicator ◽

The Cancer Genome Atlas ◽

Mrna Levels ◽

Loss Of Function ◽

Protein Levels ◽

Kaplan Meier ◽

Cancer Genome Atlas

Abstract Background The tripartite motif (TRIM) family proteins exhibit oncogenic roles in various cancers. The roles of TRIM27, a member of the TRIM super family, in renal cell carcinoma (RCC) remained unexplored. In the current study, we aimed to investigate the clinical impact and roles of TRIM27 in the development of RCC. Methods The mRNA levels of TRIM27 and Kaplan–Meier survival of RCC were analyzed from The Cancer Genome Atlas database. Real-time PCR and Western blotting were used to measure the mRNA and protein levels of TRIM27 both in vivo and in vitro. siRNA and TRIM27 were exogenously overexpressed in RCC cell lines to manipulate TRIM27 expression. Results We discovered that TRIM27 was elevated in RCC patients, and the expression of TRIM27 was closely correlated with poor prognosis. The loss of function and gain of function results illustrated that TRIM27 promotes cell proliferation and inhibits apoptosis in RCC cell lines. Furthermore, TRIM27 expression was positively associated with NF-κB expression in patients with RCC. Blocking the activity of NF-κB attenuated the TRIM27-mediated enhancement of proliferation and inhibition of apoptosis. TRIM27 directly interacted with Iκbα, an inhibitor of NF-κB, to promote its ubiquitination, and the inhibitory effects of TRIM27 on Iκbα led to NF-κB activation. Conclusions Our results suggest that TRIM27 exhibits an oncogenic role in RCC by regulating NF-κB signaling. TRIM27 serves as a specific prognostic indicator for RCC, and strategies targeting the suppression of TRIM27 function may shed light on future therapeutic approaches.

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POLRMT mutations impair mitochondrial transcription causing neurological disease

Nature Communications ◽

10.1038/s41467-021-21279-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Monika Oláhová ◽

Bradley Peter ◽

Zsolt Szilagyi ◽

Hector Diaz-Maldonado ◽

Meenakshi Singh ◽

...

Keyword(s):

Progressive External Ophthalmoplegia ◽

Global Developmental Delay ◽

Disease Mechanism ◽

Mitochondrial Transcription ◽

Functional Studies ◽

Mtdna Deletions ◽

Molecular Nature ◽

Important Disease

AbstractWhile >300 disease-causing variants have been identified in the mitochondrial DNA (mtDNA) polymerase γ, no mitochondrial phenotypes have been associated with POLRMT, the RNA polymerase responsible for transcription of the mitochondrial genome. Here, we characterise the clinical and molecular nature of POLRMT variants in eight individuals from seven unrelated families. Patients present with global developmental delay, hypotonia, short stature, and speech/intellectual disability in childhood; one subject displayed an indolent progressive external ophthalmoplegia phenotype. Massive parallel sequencing of all subjects identifies recessive and dominant variants in the POLRMT gene. Patient fibroblasts have a defect in mitochondrial mRNA synthesis, but no mtDNA deletions or copy number abnormalities. The in vitro characterisation of the recombinant POLRMT mutants reveals variable, but deleterious effects on mitochondrial transcription. Together, our in vivo and in vitro functional studies of POLRMT variants establish defective mitochondrial transcription as an important disease mechanism.

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β-elemene alleviates airway stenosis via the ILK/Akt pathway modulated by MIR143HG sponging miR-1275

Cellular & Molecular Biology Letters ◽

10.1186/s11658-021-00261-0 ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Guoying Zhang ◽

Cheng Xue ◽

Yiming Zeng

Keyword(s):

Cell Cycle ◽

Cell Viability ◽

Cell Model ◽

Protective Efficacy ◽

Rabbit Model ◽

Akt Pathway ◽

Loss Of Function ◽

Airway Stenosis

Abstract Background We have previously found that β-elemene could inhibit the viability of airway granulation fibroblasts and prevent airway hyperplastic stenosis. This study aimed to elucidate the underlying mechanism and protective efficacy of β-elemene in vitro and in vivo. Methods Microarray and bioinformatic analysis were used to identify altered pathways related to cell viability in a β-elemene-treated primary cell model and to construct a β-elemene-altered ceRNA network modulating the target pathway. Loss of function and gain of function approaches were performed to examine the role of the ceRNA axis in β-elemene's regulation of the target pathway and cell viability. Additionally, in a β-elemene-treated rabbit model of airway stenosis, endoscopic and histological examinations were used to evaluate its therapeutic efficacy and further verify its mechanism of action. Results The hyperactive ILK/Akt pathway and dysregulated LncRNA-MIR143HG, which acted as a miR-1275 ceRNA to modulate ILK expression, were suppressed in β-elemene-treated airway granulation fibroblasts; β-elemene suppressed the ILK/Akt pathway via the MIR143HG/miR-1275/ILK axis. Additionally, the cell cycle and apoptotic phenotypes of granulation fibroblasts were altered, consistent with ILK/Akt pathway activity. In vivo application of β-elemene attenuated airway granulation hyperplasia and alleviated scar stricture, and histological detections suggested that β-elemene's effects on the MIR143HG/miR-1275/ILK axis and ILK/Akt pathway were in line with in vitro findings. Conclusions MIR143HG and ILK may act as ceRNA to sponge miR-1275. The MIR143HG/miR-1275/ILK axis mediates β-elemene-induced cell cycle arrest and apoptosis of airway granulation fibroblasts by modulating the ILK/Akt pathway, thereby inhibiting airway granulation proliferation and ultimately alleviating airway stenosis.

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Human Cd25+Cd4+ T Regulatory Cells Suppress Naive and Memory T Cell Proliferation and Can Be Expanded in Vitro without Loss of Function

Journal of Experimental Medicine ◽

10.1084/jem.193.11.1295 ◽

2001 ◽

Vol 193 (11) ◽

pp. 1295-1302 ◽

Cited By ~ 703

Author(s):

Megan K. Levings ◽

Romina Sangregorio ◽

Maria-Grazia Roncarolo

Keyword(s):

T Cell ◽

Peripheral Blood ◽

T Regulatory Cells ◽

Transforming Growth Factor ◽

Cytotoxic T Lymphocyte ◽

Cell Receptor ◽

Major Advance ◽

Loss Of Function

Active suppression by T regulatory (Tr) cells plays an important role in the downregulation of T cell responses to foreign and self-antigens. Mouse CD4+ Tr cells that express CD25 possess remarkable suppressive activity in vitro and in autoimmune disease models in vivo. Thus far, the existence of a similar subset of CD25+CD4+ Tr cells in humans has not been reported. Here we show that human CD25+CD4+ Tr cells isolated from peripheral blood failed to proliferate and displayed reduced expression of CD40 ligand (CD40L), in response to T cell receptor–mediated polyclonal activation, but strongly upregulated cytotoxic T lymphocyte–associated antigen (CTLA)-4. Human CD25+CD4+ Tr cells also did not proliferate in response to allogeneic antigen-presenting cells, but they produced interleukin (IL)-10, transforming growth factor (TGF)-β, low levels of interferon (IFN)-γ, and no IL-4 or IL-2. Importantly, CD25+CD4+ Tr cells strongly inhibited the proliferative responses of both naive and memory CD4+ T cells to alloantigens, but neither IL-10, TGF-β, nor CTLA-4 seemed to be directly required for their suppressive effects. CD25+CD4+ Tr cells could be expanded in vitro in the presence of IL-2 and allogeneic feeder cells and maintained their suppressive capacities. These findings that CD25+CD4+ Tr cells with immunosuppressive effects can be isolated from peripheral blood and expanded in vitro without loss of function represent a major advance towards the therapeutic use of these cells in T cell–mediated diseases.

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Long noncoding RNA LINC00941 promotes pancreatic cancer progression by competitively binding miR-335-5p to regulate ROCK1-mediated LIMK1/Cofilin-1 signaling

Cell Death and Disease ◽

10.1038/s41419-020-03316-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jie Wang ◽

Zhiwei He ◽

Jian Xu ◽

Peng Chen ◽

Jianxin Jiang

Keyword(s):

Pancreatic Cancer ◽

Cell Growth ◽

Cell Lines ◽

Cancer Progression ◽

Noncoding Rna ◽

Epithelial Mesenchymal Transition ◽

Loss Of Function ◽

Mesenchymal Transition

AbstractAn accumulation of evidence indicates that long noncoding RNAs are involved in the tumorigenesis and progression of pancreatic cancer (PC). In this study, we investigated the functions and molecular mechanism of action of LINC00941 in PC. Quantitative PCR was used to examine the expression of LINC00941 and miR-335-5p in PC tissues and cell lines, and to investigate the correlation between LINC00941 expression and clinicopathological features. Plasmid vectors or lentiviruses were used to manipulate the expression of LINC00941, miR-335-5p, and ROCK1 in PC cell lines. Gain or loss-of-function assays and mechanistic assays were employed to verify the roles of LINC00941, miR-335-5p, and ROCK1 in PC cell growth and metastasis, both in vivo and in vitro. LINC00941 and ROCK1 were found to be highly expressed in PC, while miR-335-5p exhibited low expression. High LINC00941 expression was strongly associated with larger tumor size, lymph node metastasis, and poor prognosis. Functional experiments revealed that LINC00941 silencing significantly suppressed PC cell growth, metastasis and epithelial–mesenchymal transition. LINC00941 functioned as a molecular sponge for miR-335-5p, and a competitive endogenous RNA (ceRNA) for ROCK1, promoting ROCK1 upregulation, and LIMK1/Cofilin-1 pathway activation. Our observations lead us to conclude that LINC00941 functions as an oncogene in PC progression, behaving as a ceRNA for miR-335-5p binding. LINC00941 may therefore have potential utility as a diagnostic and treatment target in this disease.

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CDK13 upregulation-induced formation of the positive feedback loop among circCDK13, miR-212-5p/miR-449a and E2F5 contributes to prostate carcinogenesis

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-020-01814-5 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Jin-Chun Qi ◽

Zhan Yang ◽

Tao Lin ◽

Long Ma ◽

Ya-Xuan Wang ◽

...

Keyword(s):

Cell Proliferation ◽

Transcriptional Activation ◽

Positive Feedback ◽

Feedback Loop ◽

Biological Effects ◽

Therapeutic Benefit ◽

Loss Of Function ◽

Positive Feedback Loop

Abstract Background Both E2F transcription factor and cyclin-dependent kinases (CDKs), which increase or decrease E2F activity by phosphorylating E2F or its partner, are involved in the control of cell proliferation, and some circRNAs and miRNAs regulate the expression of E2F and CDKs. However, little is known about whether dysregulation among E2Fs, CDKs, circRNAs and miRNAs occurs in human PCa. Methods The expression levels of CDK13 in PCa tissues and different cell lines were determined by quantitative real-time PCR and Western blot analysis. In vitro and in vivo assays were preformed to explore the biological effects of CDK13 in PCa cells. Co-immunoprecipitation anlysis coupled with mass spectrometry was used to identify E2F5 interaction with CDK13. A CRISPR-Cas9 complex was used to activate endogenous CDK13 and circCDK13 expression. Furthermore, the mechanism of circCDK13 was investigated by using loss-of-function and gain-of-function assays in vitro and in vivo. Results Here we show that CDK13 is significantly upregulated in human PCa tissues. CDK13 depletion and overexpression in PCa cells decrease and increase, respectively, cell proliferation, and the pro-proliferation effect of CDK13 is strengthened by its interaction with E2F5. Mechanistically, transcriptional activation of endogenous CDK13, but not the forced expression of CDK13 by its expression vector, remarkably promotes E2F5 protein expression by facilitating circCDK13 formation. Further, the upregulation of E2F5 enhances CDK13 transcription and promotes circCDK13 biogenesis, which in turn sponges miR-212-5p/449a and thus relieves their repression of the E2F5 expression, subsequently leading to the upregulation of E2F5 expression and PCa cell proliferation. Conclusions These findings suggest that CDK13 upregulation-induced formation of the positive feedback loop among circCDK13, miR-212-5p/miR-449a and E2F5 is responsible for PCa development. Targeting this newly identified regulatory axis may provide therapeutic benefit against PCa progression and drug resistance.

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Propofol attenuates lung ischemia/reperfusion injury though the involvement of the MALAT1/microRNA-144/GSK3β axis

Molecular Medicine ◽

10.1186/s10020-021-00332-0 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Jian-Ping Zhang ◽

Wei-Jing Zhang ◽

Miao Yang ◽

Hua Fang

Keyword(s):

Cell Apoptosis ◽

Ischemia Reperfusion Injury ◽

Glycogen Synthase ◽

Ischemia Reperfusion ◽

Inflammatory Factors ◽

Therapeutic Effects ◽

Protective Effects ◽

Loss Of Function

Abstract Background Propofol, an intravenous anesthetic, was proven to protect against lung ischemia/reperfusion (I/R) injury. However, the detailed mechanism of Propofol in lung I/R injury is still elusive. This study was designed to explore the therapeutic effects of Propofol, both in vivo and in vitro, on lung I/R injury and the underlying mechanisms related to metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/microRNA-144 (miR-144)/glycogen synthase kinase-3β (GSK3β). Methods C57BL/6 mice were used to establish a lung I/R injury model while pulmonary microvascular endothelial cells (PMVECs) were constructed as hypoxia/reperfusion (H/R) cellular model, both of which were performed with Propofol treatment. Gain- or loss-of-function approaches were subsequently employed, followed by observation of cell apoptosis in lung tissues and evaluation of proliferative and apoptotic capabilities in H/R cells. Meanwhile, the inflammatory factors, autophagosomes, and autophagy-related proteins were measured. Results Our experimental data revealed that Propofol treatment could decrease the elevated expression of MALAT1 following I/R injury or H/R induction, indicating its protection against lung I/R injury. Additionally, overexpressing MALAT1 or GSK3β promoted the activation of autophagosomes, proinflammatory factor release, and cell apoptosis, suggesting that overexpressing MALAT1 or GSK3β may reverse the protective effects of Propofol against lung I/R injury. MALAT1 was identified to negatively regulate miR-144 to upregulate the GSK3β expression. Conclusion Overall, our study demonstrated that Propofol played a protective role in lung I/R injury by suppressing autophagy and decreasing release of inflammatory factors, with the possible involvement of the MALAT1/miR-144/GSK3β axis.

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LINC00680 enhances hepatocellular carcinoma stemness behavior and chemoresistance by sponging miR-568 to upregulate AKT3

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-01854-5 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Gege Shu ◽

Huizhao Su ◽

Zhiqian Wang ◽

Shihui Lai ◽

Yan Wang ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Xenograft Model ◽

Luciferase Reporter ◽

Loss Of Function ◽

Mechanism Study ◽

Downstream Signaling ◽

Mouse Xenograft Model ◽

High Level

Abstract Background Hepatocellular carcinoma (HCC) has an extremely poor prognosis due to the development of chemoresistance, coupled with inherently increased stemness properties. Long non-coding RNAs (LncRNAs) are key regulators for tumor cell stemness and chemosensitivity. Currently the relevance between LINC00680 and tumor progression was still largely unknown, with only one study showing its significance in glioblastoma. The study herein was aimed at identifying the role of LINC00680 in the regulation HCC stemness and chemosensitivity. Methods QRT-PCR was used to detect the expression of LINC00680, miR-568 and AKT3 in tissue specimen and cell lines. Gain- or loss-of function assays were applied to access the function of LINC00680 in HCC cells, including cell proliferation and stemness properties. HCC stemness and chemosensitivity were determined by sphere formation, cell viability and colony formation. Luciferase reporter, RNA immunoprecipitation (RIP), and RNA pull-down assays were performed to examine the interaction between LINC00680 and miR-568 as well as that between miR-568 and AKT3. A nude mouse xenograft model was established for the in vivo study. Results We found that LINC00680 was remarkably upregulated in HCC tissues. Patients with high level of LINC00680 had poorer prognosis. LINC00680 overexpression significantly enhanced HCC cell stemness and decreased in vitro and in vivo chemosensitivity to 5-fluorouracil (5-Fu), whereas LINC00680 knockdown led to opposite results. Mechanism study revealed that LINC00680 regulated HCC stemness and chemosensitivity through sponging miR-568, thereby expediting the expression of AKT3, which further activated its downstream signaling molecules, including mTOR, elF4EBP1, and p70S6K. Conclusion LINC00680 promotes HCC stemness properties and decreases chemosensitivity through sponging miR-568 to activate AKT3, suggesting that LINC00680 might be a potentially important HCC diagnosis marker and therapeutic target.

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