Changes in expression of steroid receptors, their downstream target genes and their associated co-regulators during the sequential acquisition of tamoxifen resistance in vitro

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.

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MiR-30a-5p Downregulation Induces Neuronal Autophagy by Activating AMPK After 2856MHz Microwave Radiation

10.21203/rs.3.rs-1063942/v1 ◽

2021 ◽

Author(s):

Yanhui Hao ◽

Wenchao Li ◽

Hui Wang ◽

Jing Zhang ◽

Haoyu Wang ◽

...

Keyword(s):

Microwave Radiation ◽

Hippocampal Neurons ◽

Target Genes ◽

Neuronal Damage ◽

Luciferase Reporter ◽

Potential Health ◽

Downstream Target ◽

Neuronal Autophagy

Abstract Background With the development of science and technology, microwaves are being widely used. More and more attention has been paid to the potential health hazards of microwave exposure. The regulation of miR-30a-5p (miR-30a) on autophagy is involved in the pathophysiological process of many diseases. Our previous study found that 30 mW/cm2 microwave radiation could reduce miR-30a expression and activate neuronal autophagy in rat hippocampus. However, the roles played by miR-30a in microwave-induced neuronal autophagy and related mechanisms remain largely unexplored. Results In the present study, we established neuronal damage models by exposing rat hippocampal neurons and rat adrenal pheochromocytoma (PC12) cell-derived neuron-like cells to 30 mW/cm2 microwave, which resulted in miR-30a downregulation and autophagy activation in vivo and in vitro. Bioinformatics analysis was conducted, and Beclin1, Prkaa2, Irs1, Pik3r2, Rras2, Ddit4, Gabarapl2 and autophagy-related gene 12 (Atg12) were identified as potential downstream target genes of miR-30a involved in regulating autophagy. Based on our previous findings that microwave radiation can cause a neuronal energy metabolism disorder, Prkaa2, encoding adenosine 5’-monophosphate-activated protein kinase α2 (AMPKα2, an important catalytic subunit of energy sensor AMPK), was selected for further analysis. Dual-luciferase reporter assay results showed that Prkaa2 is a downstream target gene of miR-30a. Microwave radiation increased the expression and phosphorylation (Thr172) of AMPKα both in vivo and in vitro. Moreover, the transduction of cells with miR-30a mimics suppressed AMPKα2 expression, inhibited AMPKα (Thr172) phosphorylation and reduced autophagy flux in neuron-like cells. Importantly, miR-30a mimics abolished microwave-activated autophagy and inhibited microwave-induced AMPKα (Thr172) phosphorylation. Conclusions AMPKα2 was a newly founded downstream gene of miR-30a involved in autophagy regulation, and miR-30a downregulation after microwave radiation could promote neuronal autophagy by increasing AMPKα2 expression and activating AMPK signaling.

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

Development ◽

10.1242/dev.128.18.3405 ◽

2001 ◽

Vol 128 (18) ◽

pp. 3405-3413 ◽

Cited By ~ 4

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.

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Metapristone (RU486-derivative) inhibits endometrial cancer cell progress through regulating miR-492/Klf5/Nrf1 axis

10.21203/rs.2.23357/v5 ◽

2020 ◽

Author(s):

Yue Chang ◽

Min Hao ◽

Ru Jia ◽

Yihui Zhao ◽

Yixuan Cai ◽

...

Keyword(s):

Endometrial Cancer ◽

Cell Growth ◽

Cancer Cell ◽

Cell Apoptosis ◽

Target Genes ◽

Cancer Cell Growth ◽

Endometrial Cancer Cell ◽

Downstream Target

Abstract Background: Endometrial cancer is an invasive gynecological cancer prevalent in the world. The pathogenesis of endometrial cancer is related to multiple levels of regulation, referring to oestrogen, tumor-suppressor gene (e.g. PTEN ) or microRNAs (e.g. miR-23a and miR-29b). Metapristone is a hormone-related drug, which is widely used in clinical treatment of endometrial cancer. However, the underlying regulatory mechanism of metapristone on endometrial cancer is still unclear, especially the regulatory effect on microRNAs. The aim of this study is to investigate the specific molecular mechanism of metapristone regulating microRNAs in the treatment of endometrial cancer. Methods: RL95-2 cells and Ishikawa cells were used as the endometrial cancer models. MiR-492 or si-miR-492 was transfected into RL95-2 cells and Ishikawa cells to explore the role of miR-492 in endometrial cancer. The cell cancer model and mice cancer model were used to confirm the function and mechanism of metapristone affected on endometrial cancer in vitro and in vivo . Mechanically, cell proliferation was monitored using the MTT assay, cell colony formation assay and EdU assay. Luciferase reporter assay was used to identify the downstream target gene of miR492. The protein expression and RNA expression were respectively measured by western blot and qRT-PCR for cell signaling pathway research, subsequently, were verified in the mice tumor model via immunohistochemistry. Results: Metapristone as a kind of hormone-related drug significantly inhibited the endometrial cancer cell growth through regulating cell apoptosis-related gene expression. Mechanically, miR-492 and its target genes Klf5 and Nrf1 were highly expressed in the endometrial cancer cell lines, which promoted cell proliferation and inhibited cell apoptosis. Metapristone decreased the expression of miR-492 and its target genes Klf5 and Nrf1 , leading to endometrial cancer cell growth inhibition in vitro and in vivo . Conclusion: Metapristone inhibited the endometrial cancer cell growth through regulating the cell apoptosis-related signaling pathway and decreasing the expression of miR-492 and its downstream target genes ( Klf5 and Nrf1 ), which provided the theoretical basis in clinical treatment of endometrial cancer.

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Histone demethylase KDM5C is a SAHA-sensitive central hub at the crossroads of transcriptional axes involved in multiple neurodevelopmental disorders

Human Molecular Genetics ◽

10.1093/hmg/ddz254 ◽

2019 ◽

Vol 28 (24) ◽

pp. 4089-4102 ◽

Cited By ~ 3

Author(s):

Loredana Poeta ◽

Agnese Padula ◽

Benedetta Attianese ◽

Mariaelena Valentino ◽

Lucia Verrillo ◽

...

Keyword(s):

Transcription Factors ◽

Neurodevelopmental Disorders ◽

Target Genes ◽

Downstream Target ◽

Deacetylase Inhibitor ◽

Core Feature ◽

Genes Encoding ◽

Vitro Analysis ◽

In Vitro Analysis

Abstract A disproportional large number of neurodevelopmental disorders (NDDs) is caused by variants in genes encoding transcription factors and chromatin modifiers. However, the functional interactions between the corresponding proteins are only partly known. Here, we show that KDM5C, encoding a H3K4 demethylase, is at the intersection of transcriptional axes under the control of three regulatory proteins ARX, ZNF711 and PHF8. Interestingly, mutations in all four genes (KDM5C, ARX, ZNF711 and PHF8) are associated with X-linked NDDs comprising intellectual disability as a core feature. in vitro analysis of the KDM5C promoter revealed that ARX and ZNF711 function as antagonist transcription factors that activate KDM5C expression and compete for the recruitment of PHF8. Functional analysis of mutations in these genes showed a correlation between phenotype severity and the reduction in KDM5C transcriptional activity. The KDM5C decrease was associated with a lack of repression of downstream target genes Scn2a, Syn1 and Bdnf in the embryonic brain of Arx-null mice. Aiming to correct the faulty expression of KDM5C, we studied the effect of the FDA-approved histone deacetylase inhibitor suberanilohydroxamic acid (SAHA). In Arx-KO murine ES-derived neurons, SAHA was able to rescue KDM5C depletion, recover H3K4me3 signalling and improve neuronal differentiation. Indeed, in ARX/alr-1-deficient Caenorhabditis elegans animals, SAHA was shown to counteract the defective KDM5C/rbr-2-H3K4me3 signalling, recover abnormal behavioural phenotype and ameliorate neuronal maturation. Overall, our studies indicate that KDM5C is a conserved and druggable effector molecule across a number of NDDs for whom the use of SAHA may be considered a potential therapeutic strategy.

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A Limited Set of Human MicroRNA Is Deregulated in Follicular Thyroid Carcinoma

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2006-0693 ◽

2006 ◽

Vol 91 (9) ◽

pp. 3584-3591 ◽

Cited By ~ 206

Author(s):

Frank Weber ◽

Rosemary E. Teresi ◽

Christoph E. Broelsch ◽

Andrea Frilling ◽

Charis Eng

Keyword(s):

Thyroid Carcinoma ◽

Target Genes ◽

Follicular Thyroid Carcinoma ◽

Follicular Adenoma ◽

Aberrant Expression ◽

Small Noncoding Rnas ◽

Downstream Target ◽

Micro Rnas

Abstract Context: Although the pathogenesis of follicular thyroid carcinoma (FTC) and its relation to follicular adenoma (FA) remains unclear, detailed understanding of FTC carcinogenesis would facilitate addressing the scientific and clinical challenges, given that there are morphological and molecular similarities between FTC and the frequently occurring FA. Micro-RNAs (miRNAs) are a new class of small, noncoding RNAs implicated in development and cancer and may lend novel clues to FTC genesis. For the latter process, a deregulated miRNA can orchestrate the aberrant expression of several hundred target genes. Objective: The objective of the study was to identify deregulated miRNAs in FTC. Design: We used two high-density expression arrays to identify miRNAs and their target genes that are differentially expressed between FTC and FA. Validation was done by quantitative RT-PCR. We further functionally characterized the effect of deregulated miRNAs in vitro using HEK293T, FTC133, and K5 cell lines. Patients: In total, 45 primary thyroid samples (23 FTC, 20 FA, four normal control thyroid) were analyzed. Results: Two specific miRNAs, miR-197 and miR-346, were significantly overexpressed in FTC. In vitro overexpression of either miRNA induced proliferation, whereas inhibition led to growth arrest. Overexpression of miR-197 and miR-346 repressed the expression of their predicted target genes in vitro and in vivo. Conclusions: Our observations show that miR-197 and miR-346 contribute to FTC carcinogenesis. Both miRNAs and their target genes might potentially provide for novel molecular markers and act as novel targets for treatment by interference, which could potentially normalize the deregulated profile of many downstream target genes.

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NUSAP1 Promotes Gastric Cancer Tumorigenesis and Progression by Stabilizing the YAP1 Protein

Frontiers in Oncology ◽

10.3389/fonc.2020.591698 ◽

2021 ◽

Vol 10 ◽

Author(s):

Hui Guo ◽

Jianping Zou ◽

Ling Zhou ◽

Min Zhong ◽

Yan He ◽

...

Keyword(s):

Gastric Cancer ◽

Target Genes ◽

Hippo Pathway ◽

Therapeutic Targets ◽

Xenograft Model ◽

Migration And Invasion ◽

Aberrant Expression ◽

Downstream Target ◽

Tumorigenesis And Progression

The Yes-associated protein (YAP1) is a main effector of the canonical Hippo pathway, which contributes greatly to tumor initiation, progression, and metastasis in multiple cancers, including gastric cancer (GC). Due to limited knowledge of YAP1 upregulation in cancer, it is a great challenge of therapeutic targets toward the Hippo–YAP1 pathway. Here, we identify nucleolar spindle-associated protein 1 (NUSAP1) as a novel binding partner of YAP1. The upregulation of NUSAP1 is associated with unfavorable clinical outcomes in GC patients, and NUSAP1 depletion impairs its oncogenic properties in vitro and in a xenograft model. Mechanistically, we discovered that NUSAP1 functions as a positive regulator of YAP1 protein stability, thereby inducing the transcription of Hippo pathway downstream target genes, such as CTGF and CYR61. More interestingly, we find that the cancer-promoting effects of NUSAP1 on GC cell growth, migration, and invasion are mainly mediated by YAP1. Furthermore, aberrant expression of NUSAP1 and YAP1 is highly correlated in GC cell lines and tissues. We herein clarify the role of the oncogenic NUSAP1–YAP1 axis in GC tumorigenesis and progression and, therefore, provide novel therapeutic targets for GC treatment.

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Metapristone (RU486-derivative) inhibits endometrial cancer cell progress through regulating miR-492/Klf5/Nrf1 axis

Cancer Cell International ◽

10.1186/s12935-020-01682-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yue Chang ◽

Min Hao ◽

Ru Jia ◽

Yihui Zhao ◽

Yixuan Cai ◽

...

Keyword(s):

Endometrial Cancer ◽

Cell Growth ◽

Cancer Cell ◽

Cell Apoptosis ◽

Target Genes ◽

Cancer Cell Growth ◽

Endometrial Cancer Cell ◽

Downstream Target

Abstract Background Endometrial cancer is an invasive gynecological cancer prevalent in the world. The pathogenesis of endometrial cancer is related to multiple levels of regulation, referring to oestrogen, tumor-suppressor gene (e.g. PTEN) or microRNAs (e.g. miR-23a and miR-29b). Metapristone is a hormone-related drug, which is widely used in clinical treatment of endometrial cancer. However, the underlying regulatory mechanism of metapristone on endometrial cancer is still unclear, especially the regulatory effect on microRNAs. The aim of this study is to investigate the specific molecular mechanism of metapristone regulating microRNAs in the treatment of endometrial cancer. Methods RL95-2 cells and Ishikawa cells were used as the endometrial cancer models. MiR-492 or si-miR-492 was transfected into RL95-2 cells and Ishikawa cells to explore the role of miR-492 in endometrial cancer. The cell cancer model and mice cancer model were used to confirm the function and mechanism of metapristone affected on endometrial cancer in vitro and in vivo. Mechanically, cell proliferation was monitored using MTT assay, cell colony formation assay and EdU assay. Luciferase reporter assay was used to identify the downstream target gene of miR-492. The protein expression and RNA expression were respectively measured by western blot and qRT-PCR for cell signaling pathway research, subsequently, were verified in the mice tumor model via immunohistochemistry. Results Metapristone as a kind of hormone-related drug significantly inhibited the endometrial cancer cell growth through regulating cell apoptosis-related gene expression. Mechanically, miR-492 and its target genes Klf5 and Nrf1 were highly expressed in the endometrial cancer cell lines, which promoted cell proliferation and inhibited cell apoptosis. Metapristone decreased the expression of miR-492 and its target genes Klf5 and Nrf1, leading to endometrial cancer cell growth inhibition in vitro and in vivo. Conclusion Metapristone inhibited the endometrial cancer cell growth through regulating the cell apoptosis-related signaling pathway and decreasing the expression of miR-492 and its downstream target genes (Klf5 and Nrf1), which provided the theoretical basis in clinical treatment of endometrial cancer.

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Defective neurogenesis and schizophrenia-like behavior in PARP-1-deficient mice

Cell Death and Disease ◽

10.1038/s41419-019-2174-0 ◽

2019 ◽

Vol 10 (12) ◽

Cited By ~ 3

Author(s):

Seokheon Hong ◽

Jee Hyun Yi ◽

Soonje Lee ◽

Chang-Hwan Park ◽

Jong Hoon Ryu ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Neural Stem Cells ◽

Knockout Mice ◽

Target Genes ◽

Embryonic Stem ◽

Behavioral Deficits ◽

Downstream Target ◽

Parp 1

AbstractIn the current study we present evidence suggesting that PARP-1 regulates neurogenesis and its deficiency may result in schizophrenia-like behavioral deficits in mice. PARP-1 knockout neural stem cells exhibited a marked upregulation of embryonic stem cell phosphatase that can suppress the proliferative signaling of PI3K-Akt and ERK. The suppressed activity of Akt and ERK in the absence of PARP-1 results in the elevation of FOXO1 activity and its downstream target genes p21 and p27, leading to the inhibition of neural stem cell proliferation. Moreover, expression of neurogenic factors and neuronal differentiation were decreased in the PARP-1 knockout neural stem cells whereas glial differentiation was increased. In accordance with the in vitro data, PARP-1 knockout mice exhibited reduced brain weight with enlarged ventricle as well as decreased adult neurogenesis in the hippocampus. Interestingly, PARP-1 knockout mice exhibited schizophrenia-like symptoms such as anxiety, depression, social interaction deficits, cognitive impairments, and prepulse inhibition deficits. Taken together, our results suggest that PARP-1 regulates neurogenesis during development and in adult and its absence may lead to the schizophrenia-like behavioral abnormality in mice.

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