scholarly journals A critical role for miR-142 in alveolar epithelial lineage formation

2018 ◽  
Author(s):  
Amit Shrestha ◽  
Gianni Carraro ◽  
Nicolas Nottet ◽  
Ana Ivonne Vazquez-Armendariz ◽  
Susanne Herold ◽  
...  
Keyword(s):  
Critical Role ◽  
Cell Number ◽  
Relative Increase ◽  
Over Expression ◽  
Alveolar Epithelial ◽  
Lineage Differentiation ◽  
Signaling Axis ◽  
Enhanced Expression

AbstractThe development of a functional lung, capable of gas exchange, requires proper alveologenesis. Mechanisms regulating AT1 and AT2 cell maturation are poorly defined. We report the activation of the glucocorticoid pathway in an in vitro alveolar epithelial lineage differentiation assay led to increased AT2 marker Sftpc and decreased miR-142 expression. Using a constitutive KO mouse model, we further demonstrate a relative increase of AT2 and a decrease in AT1 cell number with a global decrease of AT2 gene profile signature in miR-142 KO AT2 cells. Over-expression of miR-142 in alveolar progenitor cells in vivo led to an opposite effect. Examination of the KO lungs at E18.5, revealed enhanced expression miR-142 targets like Apc, Ep300 and Kras associated with increased Ctnnb1 and p-Erk signaling. Pharmacological inhibition of Ep300-Ctnnb1 in vitro prevented an increase in Sftpc expression triggered by loss of miR-142. These results together suggest glucocorticoid-miR-142-p300 signaling axis controls pneumocyte maturation.

scholarly journals The E3 Ubiquitin Ligase NEDD4-1 Mediates Temozolomide-Resistant Glioblastoma through PTEN Attenuation and Redox Imbalance in Nrf2–HO-1 Axis

2021 ◽  
Vol 22 (19) ◽  
pp. 10247
Author(s):  
Hao-Yu Chuang ◽  
Li-Yun Hsu ◽  
Chih-Ming Pan ◽  
Narpati Wesa Pikatan ◽  
Vijesh Kumar Yadav ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Lines ◽  
Biological Effects ◽  
Critical Role ◽  
Clinical Samples ◽  
Redox Imbalance ◽  
Signaling Axis ◽  
Resistant Cells

Background: Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. It is highly resistant to chemotherapy, and tumor recurrence is common. Neuronal precursor cell-expressed developmentally downregulated 4-1 (NEDD4-1) is an E3 ligase that controls embryonic development and animal growth. NEDD4-1 regulates the tumor suppressor phosphatase and tensin homolog (PTEN), one of the major regulators of the PI3K/AKT/mTOR signaling axis, as well as the response to oxidative stress. Methods: The expression levels of NEDD4-1 in GBM tissues and different cell lines were determined by quantitative real-time polymerase chain reaction and immunohistochemistry. In vitro and in vivo assays were performed to explore the biological effects of NEDD4-1 on GBM cells. Temozolomide (TMZ)-resistant U87MG and U251 cell lines were specifically established to determine NEDD4-1 upregulation and its effects on the tumorigenicity of GBM cells. Subsequently, miRNA expression in TMZ-resistant cell lines was investigated to determine the dysregulated miRNA underlying the overexpression of NEDD4-1. Indole-3-carbinol (I3C) was used to inhibit NEDD4-1 activity, and its effect on chemoresistance to TMZ was verified. Results: NEDD4-1 was significantly overexpressed in the GBM and TMZ-resistant cells and clinical samples. NEDD4-1 was demonstrated to be a key oncoprotein associated with TMZ resistance, inducing oncogenicity and tumorigenesis of TMZ-resistant GBM cells compared with TMZ-responsive cells. Mechanistically, TMZ-resistant cells exhibited dysregulated expression of miR-3129-5p and miR-199b-3p, resulting in the induced NEDD4-1 mRNA-expression level. The upregulation of NEDD4-1 attenuated PTEN expression and promoted the AKT/NRF2/HO-1 oxidative stress signaling axis, which in turn conferred amplified defense against reactive oxygen species (ROS) and eventually higher resistance against TMZ treatment. The combination treatment of I3C, a known inhibitor of NEDD4-1, with TMZ resulted in a synergistic effect and re-sensitized TMZ-resistant tumor cells both in vitro and in vivo. Conclusions: These findings demonstrate the critical role of NEDD4-1 in regulating the redox imbalance in TMZ-resistant GBM cells via the degradation of PTEN and the upregulation of the AKT/NRF2/HO-1 signaling pathway. Targeting this regulatory axis may help eliminate TMZ-resistant glioblastoma.

Complementary functions of the antiapoptotic protein A1 and serine/threonine kinase pim-1 in the BCR/ABL-mediated leukemogenesis

Blood ◽  
2002 ◽  
Vol 99 (12) ◽  
pp. 4531-4539 ◽  
Author(s):  
Malgorzata Nieborowska-Skorska ◽  
Grazyna Hoser ◽  
Plamen Kossev ◽  
Mariusz A. Wasik ◽  
Tomasz Skorski
Keyword(s):  
Cell Cycle Progression ◽  
Critical Role ◽  
Cell Protection ◽  
Serine Threonine Kinase ◽  
Antiapoptotic Protein ◽  
Threonine Kinase ◽  
Sh2 Domains ◽  
Enhanced Expression

BCR/ABL oncogenic tyrosine kinase activates STAT5, which plays an important role in leukemogenesis. The downstream effectors of the BCR/ABL→STAT5 pathway remain poorly defined. We show here that expression of the antiapoptotic protein A1, a member of the Bcl-2 family, and the serine/threonine kinase pim-1 are enhanced by BCR/ABL. This up-regulation requires activation of STAT5 by the signaling from SH3+SH2 domains of BCR/ABL. Enhanced expression of A1 and pim-1 played a key role in the BCR/ABL-mediated cell protection from apoptosis. In addition, pim-1 promoted proliferation of the BCR/ABL-transformed cells. Both A1 and pim-1 were required to induce interleukin 3–independent cell growth, inhibit activation of caspase 3, and stimulate cell cycle progression. Moreover, simultaneous up-regulation of both A1 and pim-1 was essential for in vitro transformation and in vivo leukemogenesis mediated by BCR/ABL. These data indicate that induction of A1 and pim-1 expression may play a critical role in the BCR/ABL-dependent transformation.

scholarly journals Expression Pattern and Regulatory Role of microRNA-23a in Conjugated Linoleic Acids-Induced Apoptosis of Adipocytes

2016 ◽  
Vol 40 (3-4) ◽  
pp. 668-680 ◽  
Author(s):  
Renli Qi ◽  
Qi Wang ◽  
Jing Wang ◽  
Jinxiu Huang ◽  
Shan Jiang ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Critical Role ◽  
Fat Cells ◽  
Conjugated Linoleic Acids ◽  
Cellular Mechanisms ◽  
Over Expression ◽  
Functional Studies ◽  
Induced Apoptosis

Background/Aims: Conjugated linoleic acids (CLAs) are known to induce apoptosis in adipocytes; however, the cellular mechanisms involved remained illdefined. We explored the different apoptotic induction effects of two CLA isomers on adipocytes and then investigated the expression and function of microRNAs (miRNAs) related to the apoptosis. Methods: TUNEL and FCM assays were used to detect CLAs-induced adipocyte apoptosis. Microarrays were used to compare the differential expression of miRNAs. MiR-23a, a miRNA that showed significant changes in expression in the CLA-treated cells, was selected for the subsequent functional studies via over-expression and knock down in in vivo and in vitro experiments. Results: C9, t11-CLA exhibited a stronger induction of apoptosis in the differentiated 3T3-L1 adipocytes than t10, c12-CLA. However, t10, c12-CLA could rapidly activate NF-κB, which may have caused their different apoptotic effects. MiR-23a was markedly down-regulated by the CLAs treatment and miR-23a over-expression attenuated CLA-induced apoptosis. Apoptosis protease-activating factor 1 (APAF1) was identified as a target gene of miR-23a. In an in vivo experiment endogenous miR-23a was down-regulated in mice fed with a mixture of both CLAs. The mice also exhibited less fat deposition and more apoptotic fat cells in adipose tissue. Moreover, endogenous miR-23a was suppressed in mice via intravenous injection with an antagomir which resulted in decreased body weight, increased number of apoptotic fat cells and increased APAF1 expression in adipose tissue. Conclusion: Taken together, our results suggest that miR-23a plays a critical role in CLA-induced apoptosis in adipocytes via controlling APAF1 expression.

scholarly journals RNF141 interacts with KRAS to promote colorectal cancer progression

Oncogene ◽  
2021 ◽  
Author(s):  
Jiuna Zhang ◽  
Xiaoyu Jiang ◽  
Jie Yin ◽  
Shiying Dou ◽  
Xiaoli Xie ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Plasma Membrane ◽  
Tumor Growth ◽  
Cancer Progression ◽  
Critical Role ◽  
Ring Finger ◽  
Immunohistochemical Analysis ◽  
Bimolecular Fluorescence Complementation

AbstractRING finger proteins (RNFs) play a critical role in cancer initiation and progression. RNF141 is a member of RNFs family; however, its clinical significance, roles, and mechanism in colorectal cancer (CRC) remain poorly understood. Here, we examined the expression of RNF141 in 64 pairs of CRC and adjacent normal tissues by real-time PCR, Western blot, and immunohistochemical analysis. We found that there was more expression of RNF141 in CRC tissue compared with its adjacent normal tissue and high RNF141 expression associated with T stage. In vivo and in vitro functional experiments were conducted and revealed the oncogenic role of RNF141 in CRC. RNF141 knockdown suppressed proliferation, arrested the cell cycle in the G1 phase, inhibited migration, invasion and HUVEC tube formation but promoted apoptosis, whereas RNF141 overexpression exerted the opposite effects in CRC cells. The subcutaneous xenograft models showed that RNF141 knockdown reduced tumor growth, but its overexpression promoted tumor growth. Mechanistically, liquid chromatography-tandem mass spectrometry indicated RNF141 interacted with KRAS, which was confirmed by Co-immunoprecipitation, Immunofluorescence assay. Further analysis with bimolecular fluorescence complementation (BiFC) and Glutathione-S-transferase (GST) pull-down assays showed that RNF141 could directly bind to KRAS. Importantly, the upregulation of RNF141 increased GTP-bound KRAS, but its knockdown resulted in a reduction accordingly. Next, we demonstrated that RNF141 induced KRAS activation via increasing its enrichment on the plasma membrane not altering total KRAS expression, which was facilitated by the interaction with LYPLA1. Moreover, KRAS silencing partially abolished the effect of RNF141 on cell proliferation and apoptosis. In addition, our findings presented that RNF141 functioned as an oncogene by upregulating KRAS activity in a manner of promoting KRAS enrichment on the plasma membrane in CRC.

scholarly journals Non-invasive skin sampling of tryptophan/kynurenine ratio in vitro towards a skin cancer biomarker

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Skaidre Jankovskaja ◽  
Johan Engblom ◽  
Melinda Rezeli ◽  
György Marko-Varga ◽  
Tautgirdas Ruzgas ◽  
...  
Keyword(s):  
Skin Cancer ◽  
Relative Increase ◽  
Cancer Biomarker ◽  
Cancer Diagnostics ◽  
Sampling Time ◽  
Skin Permeability ◽  
Experimental Conditions ◽  
Non Invasive

AbstractThe tryptophan to kynurenine ratio (Trp/Kyn) has been proposed as a cancer biomarker. Non-invasive topical sampling of Trp/Kyn can therefore serve as a promising concept for skin cancer diagnostics. By performing in vitro pig skin permeability studies, we conclude that non-invasive topical sampling of Trp and Kyn is feasible. We explore the influence of different experimental conditions, which are relevant for the clinical in vivo setting, such as pH variations, sampling time, and microbial degradation of Trp and Kyn. The permeabilities of Trp and Kyn are overall similar. However, the permeated Trp/Kyn ratio is generally higher than unity due to endogenous Trp, which should be taken into account to obtain a non-biased Trp/Kyn ratio accurately reflecting systemic concentrations. Additionally, prolonged sampling time is associated with bacterial Trp and Kyn degradation and should be considered in a clinical setting. Finally, the experimental results are supported by the four permeation pathways model, predicting that the hydrophilic Trp and Kyn molecules mainly permeate through lipid defects (i.e., the porous pathway). However, the hydrophobic indole ring of Trp is suggested to result in a small but noticeable relative increase of Trp diffusion via pathways across the SC lipid lamellae, while the shunt pathway is proposed to slightly favor permeation of Kyn relative to Trp.

scholarly journals Emerging Roles for Ion Channels in Ovarian Cancer: Pathomechanisms and Pharmacological Treatment

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 668
Author(s):  
Concetta Altamura ◽  
Maria Raffaella Greco ◽  
Maria Rosaria Carratù ◽  
Rosa Angela Cardone ◽  
Jean-François Desaphy
Keyword(s):  
Ovarian Cancer ◽  
Ion Channels ◽  
Transient Receptor Potential ◽  
Critical Role ◽  
Gynecologic Cancer ◽  
Receptor Potential ◽  
Transient Receptor Potential Channels ◽  
Platinum Resistance

Ovarian cancer (OC) is the deadliest gynecologic cancer, due to late diagnosis, development of platinum resistance, and inadequate alternative therapy. It has been demonstrated that membrane ion channels play important roles in cancer processes, including cell proliferation, apoptosis, motility, and invasion. Here, we review the contribution of ion channels in the development and progression of OC, evaluating their potential in clinical management. Increased expression of voltage-gated and epithelial sodium channels has been detected in OC cells and tissues and shown to be involved in cancer proliferation and invasion. Potassium and calcium channels have been found to play a critical role in the control of cell cycle and in the resistance to apoptosis, promoting tumor growth and recurrence. Overexpression of chloride and transient receptor potential channels was found both in vitro and in vivo, supporting their contribution to OC. Furthermore, ion channels have been shown to influence the sensitivity of OC cells to neoplastic drugs, suggesting a critical role in chemotherapy resistance. The study of ion channels expression and function in OC can improve our understanding of pathophysiology and pave the way for identifying ion channels as potential targets for tumor diagnosis and treatment.

scholarly journals Loss of ferroportin induces memory impairment by promoting ferroptosis in Alzheimer’s disease

2021 ◽  
Author(s):  
Wen-Dai Bao ◽  
Pei Pang ◽  
Xiao-Ting Zhou ◽  
Fan Hu ◽  
Wan Xiong ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Memory Impairment ◽  
Iron Homeostasis ◽  
Critical Role ◽  
Gene Set Enrichment Analysis ◽  
Molecular Characteristics ◽  
Intracellular Iron

AbstractIron homeostasis disturbance has been implicated in Alzheimer’s disease (AD), and excess iron exacerbates oxidative damage and cognitive defects. Ferroptosis is a nonapoptotic form of cell death dependent upon intracellular iron. However, the involvement of ferroptosis in the pathogenesis of AD remains elusive. Here, we report that ferroportin1 (Fpn), the only identified mammalian nonheme iron exporter, was downregulated in the brains of APPswe/PS1dE9 mice as an Alzheimer’s mouse model and Alzheimer’s patients. Genetic deletion of Fpn in principal neurons of the neocortex and hippocampus by breeding Fpnfl/fl mice with NEX-Cre mice led to AD-like hippocampal atrophy and memory deficits. Interestingly, the canonical morphological and molecular characteristics of ferroptosis were observed in both Fpnfl/fl/NEXcre and AD mice. Gene set enrichment analysis (GSEA) of ferroptosis-related RNA-seq data showed that the differentially expressed genes were highly enriched in gene sets associated with AD. Furthermore, administration of specific inhibitors of ferroptosis effectively reduced the neuronal death and memory impairments induced by Aβ aggregation in vitro and in vivo. In addition, restoring Fpn ameliorated ferroptosis and memory impairment in APPswe/PS1dE9 mice. Our study demonstrates the critical role of Fpn and ferroptosis in the progression of AD, thus provides promising therapeutic approaches for this disease.

scholarly journals The role of the PZP domain of AF10 in acute leukemia driven by AF10 translocations

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Brianna J. Klein ◽  
Anagha Deshpande ◽  
Khan L. Cox ◽  
Fan Xuan ◽  
Mohamad Zandian ◽  
...  
Keyword(s):  
Critical Role ◽  
Cellular Transformation ◽  
Acute Leukemias ◽  
Hematopoietic Stem ◽  
Nucleosome Core ◽  
Stem And Progenitor Cells ◽  
Transforming Activity

AbstractChromosomal translocations of the AF10 (or MLLT10) gene are frequently found in acute leukemias. Here, we show that the PZP domain of AF10 (AF10PZP), which is consistently impaired or deleted in leukemogenic AF10 translocations, plays a critical role in blocking malignant transformation. Incorporation of functional AF10PZP into the leukemogenic CALM-AF10 fusion prevents the transforming activity of the fusion in bone marrow-derived hematopoietic stem and progenitor cells in vitro and in vivo and abrogates CALM-AF10-mediated leukemogenesis in vivo. Crystallographic, biochemical and mutagenesis studies reveal that AF10PZP binds to the nucleosome core particle through multivalent contacts with the histone H3 tail and DNA and associates with chromatin in cells, colocalizing with active methylation marks and discriminating against the repressive H3K27me3 mark. AF10PZP promotes nuclear localization of CALM-AF10 and is required for association with chromatin. Our data indicate that the disruption of AF10PZP function in the CALM-AF10 fusion directly leads to transformation, whereas the inclusion of AF10PZP downregulates Hoxa genes and reverses cellular transformation. Our findings highlight the molecular mechanism by which AF10 targets chromatin and suggest a model for the AF10PZP-dependent CALM-AF10-mediated leukemogenesis.

scholarly journals TNFα secreted by glioma associated macrophages promotes endothelial activation and resistance against anti-angiogenic therapy

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Qingxia Wei ◽  
Olivia Singh ◽  
Can Ekinci ◽  
Jaspreet Gill ◽  
Mira Li ◽  
...  
Keyword(s):  
Critical Role ◽  
Gene Expression Signature ◽  
Endothelial Activation ◽  
Tumor Vascularization ◽  
Angiogenic Therapy ◽  
Mouse Glioma ◽  
Novel Therapeutic ◽  
Tumor Area

AbstractOne of the most prominent features of glioblastoma (GBM) is hyper-vascularization. Bone marrow-derived macrophages are actively recruited to the tumor and referred to as glioma-associated macrophages (GAMs) which are thought to provide a critical role in tumor neo-vascularization. However, the mechanisms by which GAMs regulate endothelial cells (ECs) in the process of tumor vascularization and response to anti-angiogenic therapy (AATx) is not well-understood. Here we show that GBM cells secrete IL-8 and CCL2 which stimulate GAMs to produce TNFα. Subsequently, TNFα induces a distinct gene expression signature of activated ECs including VCAM-1, ICAM-1, CXCL5, and CXCL10. Inhibition of TNFα blocks GAM-induced EC activation both in vitro and in vivo and improve survival in mouse glioma models. Importantly we show that high TNFα expression predicts worse response to Bevacizumab in GBM patients. We further demonstrated in mouse model that treatment with B20.4.1.1, the mouse analog of Bevacizumab, increased macrophage recruitment to the tumor area and correlated with upregulated TNFα expression in GAMs and increased EC activation, which may be responsible for the failure of AATx in GBMs. These results suggest TNFα is a novel therapeutic that may reverse resistance to AATx. Future clinical studies should be aimed at inhibiting TNFα as a concurrent therapy in GBMs.

scholarly journals Prrx1 promotes stemness and angiogenesis via activating TGF-β/smad pathway and upregulating proangiogenic factors in glioma

2021 ◽  
Vol 12 (6) ◽  
Author(s):  
Zetao Chen ◽  
Yihong Chen ◽  
Yan Li ◽  
Weidong Lian ◽  
Kehong Zheng ◽  
...  
Keyword(s):  
Stem Cells ◽  
Therapeutic Strategy ◽  
Critical Role ◽  
Glioma Stem Cells ◽  
Promoter Regions ◽  
Aberrant Expression ◽  
Smad Pathway ◽  
Tgf Β1

AbstractGlioma is one of the most lethal cancers with highly vascularized networks and growing evidences have identified glioma stem cells (GSCs) to account for excessive angiogenesis in glioma. Aberrant expression of paired-related homeobox1 (Prrx1) has been functionally associated with cancer stem cells including GSCs. In this study, Prrx1 was found to be markedly upregulated in glioma specimens and elevated Prrx1 expression was inversely correlated with prognosis of glioma patients. Prrx1 potentiated stemness acquisition in non-stem tumor cells (NSTCs) and stemness maintenance in GSCs, accompanied with increased expression of stemness markers such as SOX2. Prrx1 also promoted glioma angiogenesis by upregulating proangiogenic factors such as VEGF. Consistently, silencing Prrx1 markedly inhibited glioma proliferation, stemness, and angiogenesis in vivo. Using a combination of subcellular proteomics and in vitro analyses, we revealed that Prrx1 directly bound to the promoter regions of TGF-β1 gene, upregulated TGF-β1 expression, and ultimately activated the TGF-β/smad pathway. Silencing TGF-β1 mitigated the malignant behaviors induced by Prrx1. Activation of this pathway cooperates with Prrx1 to upregulate the expression of stemness-related genes and proangiogenic factors. In summary, our findings revealed that Prrx1/TGF-β/smad signal axis exerted a critical role in glioma stemness and angiogeneis. Disrupting the function of this signal axis might represent a new therapeutic strategy in glioma patients.

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