In vivo epigenetic editing of Sema6a promoter reverses transcallosal dysconnectivity caused by C11orf46/Arl14ep risk gene

Abstract Many neuropsychiatric risk genes contribute to epigenetic regulation but little is known about specific chromatin-associated mechanisms governing the formation of neuronal connectivity. Here we show that transcallosal connectivity is critically dependent on C11orf46, a nuclear protein encoded in the chromosome 11p13 WAGR risk locus. C11orf46 haploinsufficiency was associated with hypoplasia of the corpus callosum. C11orf46 knockdown disrupted transcallosal projections and was rescued by wild type C11orf46 but not the C11orf46R236H mutant associated with intellectual disability. Multiple genes encoding key regulators of axonal development, including Sema6a, were hyperexpressed in C11orf46-knockdown neurons. RNA-guided epigenetic editing of Sema6a gene promoters via a dCas9-SunTag system with C11orf46 binding normalized SEMA6A expression and rescued transcallosal dysconnectivity via repressive chromatin remodeling by the SETDB1 repressor complex. Our study demonstrates that interhemispheric communication is sensitive to locus-specific remodeling of neuronal chromatin, revealing the therapeutic potential for shaping the brain’s connectome via gene-targeted designer activators and repressor proteins.

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In vivo epigenetic editing of sema6a promoter reverses impaired transcallosal connectivity caused by C11orf46/ARL14EP neurodevelopmental risk gene

10.1101/491779 ◽

2018 ◽

Author(s):

Cyril J. Peter ◽

Atsushi Saito ◽

Yuto Hasegawa ◽

Yuya Tanaka ◽

Gabriel Perez ◽

...

Keyword(s):

Intellectual Disability ◽

Pyramidal Neurons ◽

Therapeutic Potential ◽

Wilms Tumor ◽

Regulation Of Gene Expression ◽

Gene Promoters ◽

Genes Encoding ◽

Cortical Pyramidal Neurons ◽

Epigenetic Editing

AbstractMany neuropsychiatric risk genes contribute to epigenetic regulation of gene expression but very little is known about specific chromatin-associated mechanisms governing the formation and maintenance of neuronal connectivity. Here we show that transcallosal connectivity is critically dependent on C11orf46 (also known as ARL14EP), a small nuclear protein encoded in the chromosome 11p13 Wilms Tumor, Aniridia, Genitourinary Abnormalities, intellectual disability (formerly referred to as Mental Retardation) (WAGR) risk locus. C11orf46 haploinsufficiency in WAGR microdeletion cases was associated with severe hypoplasia of the corpus callosum. In utero short hairpin RNA-mediated C11orf46 knockdown disrupted transcallosal projections of cortical pyramidal neurons, a phenotype that was rescued by wild type C11orf46 but not the C11orf46R236H mutant associated with autosomal recessive intellectual disability. Multiple genes encoding key regulators of axonal growth and differentiation, including Sema6A, were hyperexpressed in C11orf46-knockdown neurons. Importantly, RNA-guided epigenetic editing of neuronal Sema6a gene promoters via a dCas9 protein-conjugated SunTag scaffold with multimeric (10x) C11orf46 binding during early developmental periods, resulted in normalization of expression and rescue of transcallosal dysconnectivity via repressive chromatin remodeling, including up-regulated histone H3K9 methylation by the KAP1-SETDB1 repressor complex. Our study demonstrates that interhemispheric communication is highly sensitive to locus-specific remodeling of neuronal chromatin, revealing the therapeutic potential for shaping the brain’s connectome via gene-targeted designer activators and repressor proteins.

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Mutant tryptophan aporepressors with altered specificities of corepressor recognition.

Genetics ◽

10.1093/genetics/128.1.29 ◽

1991 ◽

Vol 128 (1) ◽

pp. 29-35

Author(s):

D N Arvidson ◽

M Shapiro ◽

P Youderian

Keyword(s):

Dna Binding ◽

Binding Pocket ◽

Side Chain ◽

Wild Type ◽

Mutant Proteins ◽

Naturally Occurring ◽

Repressor Complex ◽

Genes Encoding ◽

Active Repressor

Abstract The Escherichia coli trpR gene encodes tryptophan aporepressor, which binds the corepressor ligand, L-tryptophan, to form an active repressor complex. The side chain of residue valine 58 of Trp aporepressor sits at the bottom of the corepressor (L-tryptophan) binding pocket. Mutant trpR genes encoding changes of Val58 to the other 19 naturally occurring amino acids were made. Each of the mutant proteins requires a higher intracellular concentration of tryptophan for activation of DNA binding than wild-type aporepressor. Whereas wild-type aporepressor is activated better by 5-methyltryptophan (5-MT) than by tryptophan, Ile58 and other mutant aporepressors prefer tryptophan to 5-MT as corepressor, and Ala58 and Gly58 prefer 5-MT much more strongly than wild-type aporepressor in vivo. These mutant aporepressors are the first examples of DNA-binding proteins with altered specificities of cofactor recognition.

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Histone Deacetylase 3 (HDAC3), a Component of N-CoR-TBL1/R1 Chromatin Remodeling Co-Repressor Complex, Is Recruited to the Target Gene Promoters by PML-RARα To Repress the Transcription In Vivo.

Blood ◽

10.1182/blood.v106.11.2750.2750 ◽

2005 ◽

Vol 106 (11) ◽

pp. 2750-2750

Author(s):

Akihiro Tomita ◽

Akihide Atsumi ◽

Hitoshi Kiyoi ◽

Tomoki Naoe

Keyword(s):

Gene Expression ◽

Retinoic Acid ◽

Target Gene ◽

Target Genes ◽

Gene Promoters ◽

Transcription Repression ◽

Histone Deacetylase 3 ◽

Repressor Complex ◽

Endogenous Target

Abstract PML-RARα is a chimeric transcription factor deeply associated with acute promyelocytic leukemia (APL). PML-RARα plays an important role in the aberrant transcription repression on the target genes of wild type retinoic acid receptors (RARα). Pharmacological concentration of all-trans retinoic acid (ATRA) induces transcription de-repression on several target genes, and results in terminal differentiation of APL cells. However, the detailed mechanisms of transcription repression by PML-RARα in vivo are still unclear. Here we demonstrated that histone deacetylase 3 (HDAC3), one component of the N-CoR (nuclear receptor co-repressor)-TBL1/R1 (transducin beta-like protein 1/relating protein) transcription repressor protein complex, is a key regulator of the transcription repression by PML-RARα in vivo. Using immunoprecipitation (IP) assay, we first demonstrated that PML-RARα physically interacted with N-CoR/HDAC3 in vivo in the absence of ligand. The interaction was dissociated by adding ATRA in the dose dependent manner. Next we showed, using chromatin immunoprecipitation (ChIP) assay, that N-CoR/HDAC3 co-repressor complex was recruited to the endogenous target gene promoters (RARβ and CYP26) through PML-RARα. The neighboring histone H4 was de-acetylated and the gene expression was significantly repressed. When HDAC3 protein is knocked down by RNA interference in PML-RARα-presenting cells, the endogenous target gene expression was significantly activated. Almost the same results were also obtained when performing the luciferase reporter assay using RARβ and CYP26 promoter reporter vectors. Previously, we have shown that N-CoR-TBLR1 is recruited to the target gene promoter through PML-RARα in the absence of ligand, resulting in the transcription repression. Consistent with these data, it is strongly suggested that N-CoR/HDAC3/TBLR1 co-repressor complex is closely related to the aberrant transcription regulation by PML-RARα in APL cells. Furthermore, we also confirmed that PLZF-RARα, which is expressed in ATRA resistant APL cells, interacted with N-CoR/HDAC3/TBLR1 in ligand independent manner. These insights provide not only the basic mechanism of transcription repression by leukemia-related chimeric transcription factors, but also the new molecular targets for the transcription therapy for leukemia.

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MicroRNAs: Diverse Mechanisms of Action and Their Potential Applications as Cancer Epi-Therapeutics

Biomolecules ◽

10.3390/biom10091285 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1285

Author(s):

Anna Sadakierska-Chudy

Keyword(s):

Tumor Suppressor ◽

Cancer Progression ◽

Therapeutic Potential ◽

Translation Regulation ◽

Gene Promoters ◽

Protein Coding ◽

Mirna Genes ◽

Potential Applications

Usually, miRNAs function post-transcriptionally, by base-pairing with the 3′UTR of target mRNAs, repressing protein synthesis in the cytoplasm. Furthermore, other regions including gene promoters, as well as coding and 5′UTR regions of mRNAs are able to interact with miRNAs. In recent years, miRNAs have emerged as important regulators of both translational and transcriptional programs. The expression of miRNA genes, similar to protein-coding genes, can be epigenetically regulated, in turn miRNA molecules (named epi-miRs) are able to regulate epigenetic enzymatic machinery. The most recent line of evidence indicates that miRNAs can influence physiological processes, such as embryonic development, cell proliferation, differentiation, and apoptosis as well as pathological processes (e.g., tumorigenesis) through epigenetic mechanisms. Some tumor types show repression of tumor-suppressor epi-miRs resulting in cancer progression and metastasis, hence these molecules have become novel therapeutic targets in the last few years. This review provides information about miRNAs involvement in the various levels of transcription and translation regulation, as well as discusses therapeutic potential of tumor-suppressor epi-miRs used in in vitro and in vivo anti-cancer therapy.

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Gene Silencing using siRNA for Preventing Liver Ischaemia-Reperfusion Injury

Current Pharmaceutical Design ◽

10.2174/1381612824666180807124356 ◽

2018 ◽

Vol 24 (23) ◽

pp. 2692-2700 ◽

Cited By ~ 1

Author(s):

H. Susana Marinho ◽

Paulo Marcelino ◽

Helena Soares ◽

Maria Luísa Corvo

Keyword(s):

Gene Silencing ◽

Reperfusion Injury ◽

Therapeutic Potential ◽

Major Complication ◽

Ischaemia Reperfusion Injury ◽

Small Interference Rna ◽

Ischaemia Reperfusion ◽

Promising Therapeutic Approach ◽

Sirna Therapy

Background: Ischaemia-reperfusion injury (IRI), a major complication occurring during organ transplantation, involves an initial ischemia insult, due to loss of blood supply, followed by an inflammation-mediated reperfusion injury. A variety of molecular targets and pathways involved in liver IRI have been identified. Gene silencing through RNA interference (RNAi) by means of small interference RNA (siRNA) targeting mediators of IRI is a promising therapeutic approach. Objective: This study aims at reviewing the use of siRNAs as therapeutic agents to prevent IRI during liver transplantation. Method: We review the crucial choice of siRNA targets and the advantages and problems of the use of siRNAs. Results: We propose possible targets for siRNA therapy during liver IRI. Moreover, we discuss how drug delivery systems, namely liposomes, may improve siRNA therapy by increasing siRNA stability in vivo and avoiding siRNA off-target effects. Conclusion: siRNA therapeutic potential to preclude liver IRI can be improved by a better knowledge of what molecules to target and by using more efficient delivery strategies.

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Phytosomal Curcumin Elicits Anti-tumor Properties Through Suppression of Angiogenesis, Cell Proliferation and Induction of Oxidative Stress in Colorectal Cancer

Current Pharmaceutical Design ◽

10.2174/1381612825666190110145151 ◽

2019 ◽

Vol 24 (39) ◽

pp. 4626-4638 ◽

Cited By ~ 13

Author(s):

Reyhaneh Moradi-Marjaneh ◽

Seyed M. Hassanian ◽

Farzad Rahmani ◽

Seyed H. Aghaee-Bakhtiari ◽

Amir Avan ◽

...

Keyword(s):

Oxidative Stress ◽

Colorectal Cancer ◽

Therapeutic Potential ◽

Vegf Signaling ◽

Anticancer Effects ◽

Inhibition Of Angiogenesis ◽

Underlying Mechanisms ◽

Apoptotic Activity

Background: Colorectal cancer (CRC) is one of the most common causes of cancer-associated mortality in the world. Anti-tumor effect of curcumin has been shown in different cancers; however, the therapeutic potential of novel phytosomal curcumin, as well as the underlying molecular mechanism in CRC, has not yet been explored. Methods: The anti-proliferative, anti-migratory and apoptotic activity of phytosomal curcumin in CT26 cells was assessed by MTT assay, wound healing assay and Flow cytometry, respectively. Phytosomal curcumin was also tested for its in-vivo activity in a xenograft mouse model of CRC. In addition, oxidant/antioxidant activity was examined by DCFH-DA assay in vitro, measurement of malondialdehyde (MDA), Thiol and superoxidedismutase (SOD) and catalase (CAT) activity and also evaluation of expression levels of Nrf2 and GCLM by qRT-PCR in tumor tissues. In addition, the effect of phytosomal curcumin on angiogenesis was assessed by the measurement of VEGF-A and VEGFR-1 and VEGF signaling regulatory microRNAs (miRNAs) in tumor tissue. Results: Phytosomal curcumin exerts anti-proliferative, anti-migratory and apoptotic activity in-vitro. It also decreases tumor growth and augmented 5-fluorouracil (5-FU) anti-tumor effect in-vivo. In addition, our data showed that induction of oxidative stress and inhibition of angiogenesis through modulation of VEGF signaling regulatory miRNAs might be underlying mechanisms by which phytosomal curcumin exerted its antitumor effect. Conclusion: Our data confirmed this notion that phytosomal curcumin administrates anticancer effects and can be used as a complementary treatment in clinical settings.

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Medicinal Plants and Bioactive Compounds for Diabetes Management: Important Advances for Drug Discovery

Current Pharmaceutical Design ◽

10.2174/1381612826666200928160357 ◽

2020 ◽

Vol 26 ◽

Author(s):

Kondeti Ramudu Shanmugam ◽

Bhasha Shanmugam ◽

Gangigunta Venkatasubbaiah ◽

Sahukari Ravi ◽

Kesireddy Sathyavelu Reddy

Keyword(s):

Herbal Medicine ◽

Medicinal Plants ◽

Bioactive Compounds ◽

Diabetes Management ◽

Therapeutic Potential ◽

Public Health Problem ◽

In Vivo Studies ◽

Major Public Health Problem

Background : Diabetes is a major public health problem in the world. It affects each and every part of the human body and also leads to organ failure. Hence, great progress made in the field of herbal medicine and diabetic research. Objectives: Our review will focus on the effect of bioactive compounds of medicinal plants which are used to treat diabetes in India and other countries. Methods: Information regarding diabetes, oxidative stress, medicinal plants and bioactive compounds were collected from different search engines like Science direct, Springer, Wiley online library, Taylor and francis, Bentham Science, Pubmed and Google scholar. Data was analyzed and summarized in the review. Results and Conclusion: Anti-diabetic drugs that are in use have many side effects on vital organs like heart, liver, kidney and brain. There is an urgent need for alternative medicine to treat diabetes and their disorders. In India and other countries herbal medicine was used to treat diabetes. Many herbal plants have antidiabetic effects. The plants like ginger, phyllanthus, curcumin, aswagandha, aloe, hibiscus and curcuma showed significant anti-hyperglycemic activities in experimental models and humans. The bioactive compounds like Allicin, azadirachtin, cajanin, curcumin, querceitin, gingerol possesses anti-diabetic, antioxidant and other pharmacological properties. This review focuses on the role of bioactive compounds of medicinal plants in prevention and management of diabetes. Conclusion: Moreover, our review suggests that bioactive compounds have the potential therapeutic potential against diabetes. However, further in vitro and in vivo studies are needed to validate these findings.

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Induction of Apoptosis by Nano‐Synthesized Complexes of H2L and its Cu(II) Complex in Human Hepatocellular Carcinoma Cells

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200204103756 ◽

2020 ◽

Vol 20 ◽

Author(s):

Thoria Diab ◽

Tarek M. Mohamed ◽

Alaa Hamed ◽

Mohamed Gaber

Keyword(s):

Cell Cycle ◽

Metal Complexes ◽

Hepg2 Cells ◽

Therapeutic Potential ◽

Free Ligand ◽

Organometallic Complexes ◽

Phase Cell ◽

Sod Activity ◽

Induced Apoptosis

Background: Chemotherapy is currently the most utilized treatment for cancer. Therapeutic potential of metal complexes in cancer therapy has attracted a lot of interest. The mechanisms of action of most organometallic complexes are poorly understood. Objective: This study was designed to explore the mechanisms governing the anti-proliferative effect of the free ligand N1,N6‐bis((2‐hydroxynaphthalin‐1‐yl)methinyl)) adipohydrazone (H2L) and its complexes of Mn(II), Co(II), Ni(II) and Cu(II). Methods: Cells were exposed to H2L or its metal complexes where cell viability determined by MTT assay. Cell cycle was analysed by flow cytometry. In addition, qRT-PCR was used to monitor the expression of Bax and Bcl-2. Moreover, molecular docking was carried out to find the potentiality of Cu(II) complex as an inhibitor of Adenosine Deaminase (ADA). ADA, Superoxide Dismutase (SOD) and reduced Glutathione (GSH) levels were measured in the most affected cancer cell line. Results: The obtained results demonstrated that H2L and its Cu(II) complex exhibited a strong cytotoxic activity compared to other complexes against HepG2 cells (IC50 = 4.14±0.036μM/ml and 3.2±0.02μM/ml), respectively. Both H2L and its Cu(II) complex induced G2/M phase cell cycle arrest in HepG2 cells. Additionally, they induced apoptosis in HepG2 cells via upregulation of Bax and downregulation of Bcl-2. Interestingly, the activity of ADA was decreased by 2.8 fold in HepG2 cells treated with Cu(II) complex compared to untreated cells. An increase of SOD activity and GSH level in HepG2 cells compared to control was observed. Conclusion: The results concluded that Cu(II) complex of H2L induced apoptosis in HepG2 cells. Further studies are needed to confirm its anti-cancer effect in vivo.

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mRNA-Driven Generation of Transgene-Free Neural Stem Cells from Human Urine-Derived Cells

Cells ◽

10.3390/cells8091043 ◽

2019 ◽

Vol 8 (9) ◽

pp. 1043 ◽

Cited By ~ 1

Author(s):

Phil Jun Kang ◽

Daryeon Son ◽

Tae Hee Ko ◽

Wonjun Hong ◽

Wonjin Yun ◽

...

Keyword(s):

Stem Cells ◽

Neural Stem Cells ◽

Human Urine ◽

Neurological Disorders ◽

Therapeutic Potential ◽

Embryonic Stem ◽

Global Gene Expression ◽

Patient Specific ◽

Human Neural Stem Cells

Human neural stem cells (NSCs) hold enormous promise for neurological disorders, typically requiring their expandable and differentiable properties for regeneration of damaged neural tissues. Despite the therapeutic potential of induced NSCs (iNSCs), a major challenge for clinical feasibility is the presence of integrated transgenes in the host genome, contributing to the risk for undesired genotoxicity and tumorigenesis. Here, we describe the advanced transgene-free generation of iNSCs from human urine-derived cells (HUCs) by combining a cocktail of defined small molecules with self-replicable mRNA delivery. The established iNSCs were completely transgene-free in their cytosol and genome and further resembled human embryonic stem cell-derived NSCs in the morphology, biological characteristics, global gene expression, and potential to differentiate into functional neurons, astrocytes, and oligodendrocytes. Moreover, iNSC colonies were observed within eight days under optimized conditions, and no teratomas formed in vivo, implying the absence of pluripotent cells. This study proposes an approach to generate transplantable iNSCs that can be broadly applied for neurological disorders in a safe, efficient, and patient-specific manner.

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GSK-3β in Pancreatic Cancer: Spotlight on 9-ING-41, Its Therapeutic Potential and Immune Modulatory Properties

Biology ◽

10.3390/biology10070610 ◽

2021 ◽

Vol 10 (7) ◽

pp. 610

Author(s):

Robin Park ◽

Andrew L. Coveler ◽

Ludimila Cavalcante ◽

Anwaar Saeed

Keyword(s):

Pancreatic Cancer ◽

Therapeutic Potential ◽

Glycogen Synthase ◽

Glycogen Synthase Kinase ◽

Glycogen Synthase Kinase 3 ◽

In Vivo Models ◽

Gsk 3Β ◽

Early Phase Clinical Trials

Glycogen synthase kinase-3 beta is a ubiquitously and constitutively expressed molecule with pleiotropic function. It acts as a protooncogene in the development of several solid tumors including pancreatic cancer through its involvement in various cellular processes including cell proliferation, survival, invasion and metastasis, as well as autophagy. Furthermore, the level of aberrant glycogen synthase kinase-3 beta expression in the nucleus is inversely correlated with tumor differentiation and survival in both in vitro and in vivo models of pancreatic cancer. Small molecule inhibitors of glycogen synthase kinase-3 beta have demonstrated therapeutic potential in pre-clinical models and are currently being evaluated in early phase clinical trials involving pancreatic cancer patients with interim results showing favorable results. Moreover, recent studies support a rationale for the combination of glycogen synthase kinase-3 beta inhibitors with chemotherapy and immunotherapy, warranting the evaluation of novel combination regimens in the future.

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