Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
Add more filters










Publication year range
1.
Cell Death Dis ; 13(9): 766, 2022 09 05.
Article in English | MEDLINE | ID: mdl-36064715

ABSTRACT

Zinc Finger transcription factors are crucial in modulating various cellular processes, including differentiation. Chromatin reader Zinc Finger MYND (Myeloid, Nervy, and DEAF-1) type containing 8 (ZMYND8), an All-Trans Retinoic Acid (ATRA)-responsive gene, was previously shown to play a crucial role in promoting the expression of neuronal-lineage committed genes. Here, we report that ZMYND8 promotes neuronal differentiation by positively regulating canonical MAPT protein-coding gene isoform, a key player in the axonal development of neurons. Additionally, ZMYND8 modulates gene-isoform switching by epigenetically silencing key regulatory regions within the MAPT gene, thereby suppressing the expression of non-protein-coding isoforms such as MAPT213. Genetic deletion of ZMYND8 led to an increase in the MAPT213 that potentially suppressed the parental MAPT protein-coding transcript expression related to neuronal differentiation programs. In addition, ectopic expression of MAPT213 led to repression of MAPT protein-coding transcript. Similarly, ZMYND8-driven transcription regulation was also observed in other neuronal differentiation-promoting genes. Collectively our results elucidate a novel mechanism of ZMYND8-dependent transcription regulation of different neuronal lineage committing genes, including MAPT, to promote neural differentiation.


Subject(s)
RNA, Long Noncoding , Cell Differentiation/genetics , Chromatin , Gene Expression Regulation , RNA, Long Noncoding/genetics , Tretinoin/pharmacology , Tumor Suppressor Proteins/metabolism
2.
J Biomol Struct Dyn ; 40(1): 249-262, 2022 01.
Article in English | MEDLINE | ID: mdl-32838660

ABSTRACT

Drug re-purposing might be a fast and efficient way of drug development against the novel coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We applied a bioinformatics approach using molecular dynamics and docking to identify FDA-approved drugs that can be re-purposed to potentially inhibit the non-structural protein 9 (Nsp9) replicase and spike proteins in SARS-CoV-2. We performed virtual screening of FDA-approved compounds, including antiviral, anti-malarial, anti-parasitic, anti-fungal, anti-tuberculosis, and active phytochemicals against the Nsp9 replicase and spike proteins. Selected hit compounds were identified based on their highest binding energy and favorable absorption, distribution, metabolism and excretion (ADME) profile. Conivaptan, an arginine vasopressin antagonist drug exhibited the highest binding energy (-8.4 Kcal/mol) and maximum stability with the amino acid residues present at the active site of the Nsp9 replicase. Tegobuvir, a non-nucleoside inhibitor of the hepatitis C virus, also exhibited maximum stability along with the highest binding energy (-8.1 Kcal/mol) at the active site of the spike proteins. Molecular docking scores were further validated by molecular dynamics using Schrodinger, which supported the strong stability of ligands with the proteins at their active sites through water bridges, hydrophobic interactions, and H-bonding. Our findings suggest Conivaptan and Tegobuvir as potential therapeutic agents against SARS-CoV-2. Further in vitro and in vivo validation and evaluation are warranted to establish how these drug compounds target the Nsp9 replicase and spike proteins.


Subject(s)
Antiviral Agents/pharmacology , Drug Repositioning , RNA-Binding Proteins/antagonists & inhibitors , SARS-CoV-2/drug effects , Spike Glycoprotein, Coronavirus/antagonists & inhibitors , Viral Nonstructural Proteins/antagonists & inhibitors , COVID-19 , Humans , Molecular Docking Simulation , Molecular Dynamics Simulation
3.
J Endocr Soc ; 5(11): bvab153, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34703959

ABSTRACT

Long noncoding RNAs (lncRNAs) have emerged as critical regulators of biological processes. However, the aberrant expression of an isoform from the same lncRNA gene could lead to RNA with altered functions due to changes in their conformations, leading to diseases. Here, we describe a detailed characterization of the gene that encodes long intergenic non-protein-coding RNA 01016 (LINC01016, also known as LncRNA1195) with a focus on its structure, exon usage, and expression in human and macaque tissues. In this study we show that it is among the highly expressed lncRNAs in the testis, exclusively conserved among nonhuman primates, suggesting its recent evolution and is processed into 12 distinct RNAs in testis, cervix, and uterus tissues. Further, we integrate de novo annotation of expressed LINC01016 transcripts and isoform-dependent gene expression analyses to show that human LINC01016 is a multiexon gene, processed through differential exon usage with isoform-specific roles. Furthermore, in cervical, testicular, and uterine cancers, LINC01016 isoforms are differentially expressed, and their expression is predictive of survival in these cancers. This study has revealed an essential aspect of lncRNA biology, rarely associated with coding RNAs, that lncRNA genes are precisely processed to generate isoforms with distinct biological roles in specific tissues.

4.
Semin Cancer Biol ; 69: 166-177, 2021 02.
Article in English | MEDLINE | ID: mdl-31715247

ABSTRACT

Nanotechnology has been the latest approach for diagnosis and treatment for cancer, which opens up a new alternative therapeutic drug delivery option to treat disease. Nanoparticles (NPs) display a broad role in cancer diagnosis and has various advantages over the other conventional chemotherapeutic drug delivery. NPs possess more specific and efficient drug delivery to the targeted tissue, cell, or organs and minimize the risk of side effects. NPs undergo passive and active mode of drug targets to tumor area with less elimination of the drug from the system. Size and surface characteristics of nanoparticles play a crucial role in modulating nanocarrier efficiency and the biodistribution of chemo drugs in the body. Several types of nanocarriers, such as polymers, dendrimers, liposome-based, and carbon-based, are studied widely in cancer therapy. Although FDA approved very few nanotechnology drugs for cancer therapy, a large number of studies are undergoing for the development of novel nanocarriers for potent cancer therapy. In this review, we discuss the details of the nano-based therapeutics and diagnostics strategies, and the potential use of nanomedicines in cancer therapy and cancer drug delivery.


Subject(s)
Antineoplastic Agents/administration & dosage , Drug Delivery Systems , Nanomedicine , Nanoparticles/administration & dosage , Neoplasms/drug therapy , Animals , Antineoplastic Agents/pharmacokinetics , Humans , Nanoparticles/chemistry , Neoplasms/pathology , Organ Specificity , Tissue Distribution
5.
Cell Death Dis ; 11(12): 1073, 2020 12 15.
Article in English | MEDLINE | ID: mdl-33323928

ABSTRACT

The major challenge in chemotherapy lies in the gain of therapeutic resistance properties of cancer cells. The relatively small fraction of chemo-resistant cancer cells outgrows and are responsible for tumor relapse, with acquired invasiveness and stemness. We demonstrate that zinc-finger MYND type-8 (ZMYND8), a putative chromatin reader, suppresses stemness, drug resistance, and tumor-promoting genes, which are hallmarks of cancer. Reinstating ZMYND8 suppresses chemotherapeutic drug doxorubicin-induced tumorigenic potential (at a sublethal dose) and drug resistance, thereby resetting the transcriptional program of cells to the epithelial state. The ability of ZMYND8 to chemo-sensitize doxorubicin-treated metastatic breast cancer cells by downregulating tumor-associated genes was further confirmed by transcriptome analysis. Interestingly, we observed that ZMYND8 overexpression in doxorubicin-treated cells stimulated those involved in a good prognosis in breast cancer. Consistently, sensitizing the cancer cells with ZMYND8 followed by doxorubicin treatment led to tumor regression in vivo and revert back the phenotypes associated with drug resistance and stemness. Intriguingly, ZMYND8 modulates the bivalent or poised oncogenes through its association with KDM5C and EZH2, thereby chemo-sensitizing the cells to chemotherapy for better disease-free survival. Collectively, our findings indicate that poised chromatin is instrumental for the acquisition of chemo-resistance by cancer cells and propose ZMYND8 as a suitable epigenetic tool that can re-sensitize the chemo-refractory breast carcinoma.


Subject(s)
Oncogenes , Tumor Suppressor Proteins/metabolism , Animals , Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Carcinogenesis/drug effects , Carcinogenesis/genetics , Carcinogenesis/pathology , Cell Line, Tumor , Cell Movement/drug effects , Cell Movement/genetics , Down-Regulation/drug effects , Down-Regulation/genetics , Doxorubicin/pharmacology , Doxorubicin/therapeutic use , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Enhancer of Zeste Homolog 2 Protein/metabolism , Epigenesis, Genetic/drug effects , Epithelial-Mesenchymal Transition/drug effects , Epithelial-Mesenchymal Transition/genetics , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Genome, Human , Histone Demethylases/metabolism , Humans , Mice, Inbred BALB C , Mice, Nude , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Phenotype , RNA, Messenger/genetics , RNA, Messenger/metabolism , Treatment Outcome , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/pathology
6.
Cancers (Basel) ; 12(6)2020 Jun 10.
Article in English | MEDLINE | ID: mdl-32532008

ABSTRACT

Hypoxanthine phosphoribosyl transferase 1 (HPRT1) is traditionally believed to be a housekeeping gene; however, recent reports suggest that it is upregulated in several cancers and is associated with clinical outcomes. HPRT1 is located on chromosome X and encodes the HPRT enzyme, which functions in recycling nucleotides to supply for DNA and RNA synthesis in actively dividing cells. Here, we used transcriptomic analyses to interrogate its expression across all known cancer types and elucidated its role in regulating gene expression in breast cancer. We observed elevated HPRT1 RNA levels in malignant tissues when compared to normal controls, indicating its potential as a diagnostic and prognostic marker. Further, in breast cancer, the subtype-specific analysis showed that its expression was highest in basal and triple-negative breast cancer, and HPRT1 knockdown in breast cancer cells suggested that HPRT1 positively regulates genes related to cancer pathways. Collectively, our results essentially highlight the importance of and change the way in which HPRT1's function is studied in biology, warranting careful examination of its role in cancer.

7.
Int J Mol Sci ; 21(10)2020 May 25.
Article in English | MEDLINE | ID: mdl-32466143

ABSTRACT

Genome-wide RNA sequencing has shown that only a small fraction of the human genome is transcribed into protein-coding mRNAs. While once thought to be "junk" DNA, recent findings indicate that the rest of the genome encodes many types of non-coding RNA molecules with a myriad of functions still being determined. Among the non-coding RNAs, long non-coding RNAs (lncRNA) and enhancer RNAs (eRNA) are found to be most copious. While their exact biological functions and mechanisms of action are currently unknown, technologies such as next-generation RNA sequencing (RNA-seq) and global nuclear run-on sequencing (GRO-seq) have begun deciphering their expression patterns and biological significance. In addition to their identification, it has been shown that the expression of long non-coding RNAs and enhancer RNAs can vary due to spatial, temporal, developmental, or hormonal variations. In this review, we explore newly reported information on estrogen-regulated eRNAs and lncRNAs and their associated biological functions to help outline their markedly prominent roles in estrogen-dependent signaling.


Subject(s)
Enhancer Elements, Genetic , Estrogens/metabolism , RNA, Long Noncoding/metabolism , RNA, Small Untranslated/metabolism , Signal Transduction , Gene Expression Regulation, Neoplastic , Humans , RNA, Long Noncoding/genetics , RNA, Small Untranslated/genetics , Transcriptional Activation
8.
Mol Cell Endocrinol ; 510: 110819, 2020 06 15.
Article in English | MEDLINE | ID: mdl-32311422

ABSTRACT

Recent technical and other advances in genomics provide unique opportunities to improve our understanding of human physiology and disease predisposition through a detailed analysis of gene structure and expression by examining data in public genome and gene-expression repositories. Yet, the vast majority of human genes remain understudied. This is particularly true of genes for long noncoding RNAs (lncRNAs). Here, we describe the detailed characterization of MIR503HG, a lncRNA gene found on the X chromosome in humans. Using information extracted from public databases, we show that human MIR503HG is a 5-exon gene, and that it is highly conserved among 5 non-human primates spanning over 85 million years ago of evolutionary diversification. MIR503HG is transcribed and processed into multiple distinct RNAs in each of these species through differential exon use and alternative RNA splicing, with a higher abundance of transcripts being found in reproductive tissues, especially during the early stages of ovary and testis development, indicating a possible role in reproductive biology. Furthermore, in select reproductive system cancers, MIR503HG transcripts are downregulated, with higher levels of RNA expression being associated with clinical outcomes. Collectively, these investigations show how the use of genomic, gene expression, and other genetic resources can lead to new insights about human biology and disease, and argue that MIR503HG is worthy of additional study.


Subject(s)
Gene Expression Regulation , RNA, Long Noncoding/chemistry , RNA, Long Noncoding/genetics , Animals , Genome, Human , Humans , Primates , Prognosis , Protein Binding , RNA, Long Noncoding/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism
9.
Adv Clin Chem ; 95: 105-147, 2020.
Article in English | MEDLINE | ID: mdl-32122521

ABSTRACT

Long noncoding RNAs (lncRNAs) have recently gained considerable attention as key players in biological regulation; however, the mechanisms by which lncRNAs govern various disease processes remain mysterious and are just beginning to be understood. The ease of next-generation sequencing technologies has led to an explosion of genomic information, especially for the lncRNA class of noncoding RNAs. LncRNAs exhibit the characteristics of mRNAs, such as polyadenylation, 5' methyl capping, RNA polymerase II-dependent transcription, and splicing. These transcripts comprise more than 200 nucleotides (nt) and are not translated into proteins. Directed interrogation of annotated lncRNAs from RNA-Seq datasets has revealed dramatic differences in their expression, largely driven by alterations in transcription, the cell cycle, and RNA metabolism. The fact that lncRNAs are expressed cell- and tissue-specifically makes them excellent biomarkers for ongoing biological events. Notably, lncRNAs are differentially expressed in several cancers and show a distinct association with clinical outcomes. Novel methods and strategies are being developed to study lncRNA function and will provide researchers with the tools and opportunities to develop lncRNA-based therapeutics for cancer.


Subject(s)
Antineoplastic Agents/pharmacology , Neoplasms/drug therapy , RNA, Long Noncoding/antagonists & inhibitors , Animals , Humans , Neoplasms/genetics , Neoplasms/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
10.
Nat Med ; 25(1): 130-140, 2019 01.
Article in English | MEDLINE | ID: mdl-30510251

ABSTRACT

In T lymphocytes, the Wiskott-Aldrich Syndrome protein (WASP) and WASP-interacting-protein (WIP) regulate T cell antigen receptor (TCR) signaling, but their role in lymphoma is largely unknown. Here we show that the expression of WASP and WIP is frequently low or absent in anaplastic large cell lymphoma (ALCL) compared to other T cell lymphomas. In anaplastic lymphoma kinase-positive (ALK+) ALCL, WASP and WIP expression is regulated by ALK oncogenic activity via its downstream mediators STAT3 and C/EBP-ß. ALK+ lymphomas were accelerated in WASP- and WIP-deficient mice. In the absence of WASP, active GTP-bound CDC42 was increased and the genetic deletion of one CDC42 allele was sufficient to impair lymphoma growth. WASP-deficient lymphoma showed increased mitogen-activated protein kinase (MAPK) pathway activation that could be exploited as a therapeutic vulnerability. Our findings demonstrate that WASP and WIP are tumor suppressors in T cell lymphoma and suggest that MAP-kinase kinase (MEK) inhibitors combined with ALK inhibitors could achieve a more potent therapeutic effect in ALK+ ALCL.


Subject(s)
Lymphoma, T-Cell/metabolism , Tumor Suppressor Proteins/metabolism , Wiskott-Aldrich Syndrome Protein/metabolism , Anaplastic Lymphoma Kinase/metabolism , Animals , CCAAT-Enhancer-Binding Protein-beta/metabolism , Cell Line, Tumor , Cell Proliferation , Cell Survival , Cytoskeletal Proteins/metabolism , Down-Regulation , Enzyme Activation , Extracellular Signal-Regulated MAP Kinases/metabolism , Guanosine Triphosphate/metabolism , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Kaplan-Meier Estimate , Lymphoma, T-Cell/enzymology , Lymphoma, T-Cell/pathology , MAP Kinase Signaling System , Mice , Protein Binding , STAT3 Transcription Factor/metabolism , T-Lymphocytes/immunology , Wiskott-Aldrich Syndrome Protein/deficiency , cdc42 GTP-Binding Protein/metabolism
11.
CNS Neurol Disord Drug Targets ; 17(9): 680-688, 2018.
Article in English | MEDLINE | ID: mdl-29938622

ABSTRACT

BACKGROUND AND OBJECTIVE: A steep rise in the incidences of neurodegenerative disorders could be the combined effect of several non-genetic factors such as increased life expectancy, environmental pollutants, lifestyle, and dietary habits, as population-level genetic change require multiple generations. Emerging evidence suggests that chronic over-nutrition induces brain metabolic stress and neuroinflammation, and are individually known to promote neurodegenerative disorders including Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD). Although the association of metabolic disorders such as diabetes, hypertension, dyslipidemia, and atherosclerosis with the dietary habits is well known, neuronal implications of diet and nutritional factors is still in its infancy. Transcriptomics and proteomics-based studies support the view that nutraceuticals target multiple neuroprotective pathways in a slow but effective manner without causing severe adverse effects, and may represent the future of tackling neurodegenerative disorders. CONCLUSION: In this article we i) review the diet/dietary supplement connection with brain metabolic stress and neuroinflammation and ii) summarize current knowledge of the effects of nutraceuticals on neurodegenerative disorders.


Subject(s)
Brain/physiopathology , Dietary Supplements , Encephalitis/pathology , Nutrients/metabolism , Stress, Physiological/physiology , Animals , Brain/metabolism , Encephalitis/therapy , Humans
12.
Steroids ; 133: 93-95, 2018 05.
Article in English | MEDLINE | ID: mdl-29317255

ABSTRACT

Long noncoding RNAs (lncRNAs) are implicated in several biological processes, including but not limited to cardiovascular physiology, reproduction, differentiation, metabolism, DNA repair, and inflammation. Under normal physiological conditions, expression of lncRNAs is tissue-specific and tightly regulated. In contrast, prevalent cancer types exhibit aberrant expression of lncRNAs. In this context, lncRNAs can drive cancer cell characteristics by controlling gene expression programs related to tumor suppressive and oncogenic functions. Hence, they can be excellent biomarkers and targets for therapeutic intervention in cancers. Understanding the molecular mechanisms by which lncRNAs drive cancer progression will improve our understanding of the etiology of cancer and suggest new ways to treat this disease. This review will provide a perspective on the role of lncRNAs in cancer initiation and progression.


Subject(s)
Neoplasms/genetics , RNA, Long Noncoding/genetics , Humans
13.
Cold Spring Harb Mol Case Stud ; 3(3): a001719, 2017 05.
Article in English | MEDLINE | ID: mdl-28487884

ABSTRACT

Gene-expression profiling and next-generation sequencing have defined diffuse large B-cell lymphoma (DLBCL), the most common lymphoma diagnosis, as a heterogeneous group of subentities. Despite ongoing explosions of data illuminating disparate pathogenic mechanisms, however, the five-drug chemoimmunotherapy combination R-CHOP remains the frontline standard treatment. This has not changed in 15 years, since the anti-CD20 monoclonal antibody rituximab was added to the CHOP backbone, which first entered use in the 1970s. At least a third of patients are not cured by R-CHOP, and relapsed or refractory DLBCL is fatal in ∼90%. Targeted small-molecule inhibitors against distinct molecular pathways activated in different subgroups of DLBCL have so far translated poorly into the clinic, justifying the ongoing reliance on R-CHOP and other long-established chemotherapy-driven combinations. New drugs and improved identification of biomarkers in real time, however, show potential to change the situation eventually, despite some recent setbacks. Here, we review established and putative molecular drivers of DLBCL identified through large-scale genomics, highlighting among other things the care that must be taken when differentiating drivers from passengers, which is influenced by the promiscuity of activation-induced cytidine deaminase. Furthermore, we discuss why, despite having so much genomic data available, it has been difficult to move toward personalized medicine for this umbrella disorder and some steps that may be taken to hasten the process.


Subject(s)
Lymphoma, Large B-Cell, Diffuse/diagnosis , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/genetics , Antibodies, Monoclonal, Murine-Derived/administration & dosage , Antineoplastic Agents/pharmacology , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cyclophosphamide/administration & dosage , Doxorubicin/administration & dosage , Gene Expression Profiling/methods , Genomics , Humans , Precision Medicine , Prednisone/administration & dosage , Rituximab/administration & dosage , Vincristine/administration & dosage
14.
Blood ; 127(10): 1297-306, 2016 Mar 10.
Article in English | MEDLINE | ID: mdl-26747246

ABSTRACT

Increasing evidence suggests that Rho family GTPases could have a critical role in the biology of T-cell lymphoma. In ALK-rearranged anaplastic large cell lymphoma (ALCL), a specific subtype of T-cell lymphoma, the Rho family GTPases Cdc42 and Rac1 are activated by the ALK oncogenic activity. In vitro studies have shown that Cdc42 and Rac1 control rather similar phenotypes of ALCL biology such as the proliferation, survival, and migration of lymphoma cells. However, their role and possible redundancy in ALK-driven lymphoma development in vivo are still undetermined. We genetically deleted Cdc42 or Rac1 in a mouse model of ALK-rearranged ALCL to show that either Cdc42 or Rac1 deletion impaired lymphoma development, modified lymphoma morphology, actin filament distribution, and migration properties of lymphoma cells. Cdc42 or Rac1 deletion primarily affected survival rather than proliferation of lymphoma cells. Apoptosis of lymphoma cells was equally induced following Cdc42 or Rac1 deletion, was associated with upregulation of the proapoptotic molecule Bid, and was blocked by Bcl2 overexpression. Remarkably, Cdc42/Rac1 double deletion, but not Cdc42 or Rac1 single deletions, completely prevented NPM-ALK lymphoma dissemination in vivo. Thus, Cdc42 and Rac1 have nonredundant roles in controlling ALK-rearranged lymphoma survival and morphology but are redundant for lymphoma dissemination, suggesting that targeting both GTPases could represent a preferable therapeutic option for ALCL treatment.


Subject(s)
Lymphoma, Large B-Cell, Diffuse/metabolism , Neuropeptides/metabolism , Oncogene Proteins, Fusion/metabolism , Protein-Tyrosine Kinases/metabolism , cdc42 GTP-Binding Protein/metabolism , rac1 GTP-Binding Protein/metabolism , Animals , BH3 Interacting Domain Death Agonist Protein/genetics , BH3 Interacting Domain Death Agonist Protein/metabolism , Cell Survival/genetics , Gene Deletion , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/pathology , Mice , Mice, Inbred NOD , Mice, SCID , Mice, Transgenic , Neuropeptides/genetics , Oncogene Proteins, Fusion/genetics , Protein-Tyrosine Kinases/genetics , cdc42 GTP-Binding Protein/genetics , rac1 GTP-Binding Protein/genetics
15.
Chem Biol ; 17(8): 903-13, 2010 Aug 27.
Article in English | MEDLINE | ID: mdl-20797619

ABSTRACT

Altered histone acetylation is associated with several diseases, including cancer. We report here that, unlike in most cancers, histones are found to be highly hyperacetylated in oral squamous cell carcinoma (OSCC; oral cancer) patient samples. Mechanistically, overexpression, as well as enhanced autoacetylation, of p300 induced by nucleophosmin (NPM1) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) causes the hyperacetylation, which is nitric oxide (NO) signal dependent. Inhibition of the histone acetyltransferase (HAT) activity of p300 by a water-soluble, small molecule inhibitor, Hydrazinocurcumin (CTK7A), substantially reduced the xenografted oral tumor growth in mice. These results, therefore, not only establish an epigenetic target for oral cancer, but also implicate a HAT inhibitor (HATi) as a potential therapeutic molecule.


Subject(s)
Curcumin/analogs & derivatives , Histone Acetyltransferases/antagonists & inhibitors , Histones/metabolism , Hydrazines/chemistry , Hydrazines/pharmacology , Mouth Neoplasms/metabolism , Nitric Oxide/metabolism , Water/chemistry , Acetylation/drug effects , Animals , Cell Proliferation/drug effects , Cellular Senescence/drug effects , Curcumin/chemistry , Curcumin/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , HeLa Cells , Histone Acetyltransferases/metabolism , Humans , Mice , Mice, Nude , Mouth Neoplasms/enzymology , Mouth Neoplasms/genetics , Mouth Neoplasms/pathology , Nuclear Proteins/metabolism , Nucleophosmin , Solubility , Up-Regulation/drug effects , p300-CBP Transcription Factors/metabolism
16.
Mol Cell Biol ; 29(18): 5115-27, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19581289

ABSTRACT

Nucleophosmin (NPM1) is a multifunctional protein involved in the regulation of centrosome duplication, ribosome biogenesis, genomic stability, histone chaperone function, and transcription. Overexpression of NPM1 is associated with cancers of diverse histological origins. Here, we have found that p300-mediated acetylation of NPM1 modulates its subcellular localization and augments its oncogenic potential. Acetylated NPM1 is predominantly localized in the nucleoplasm, where it associates with transcriptionally active RNA polymerase II. Deacetylation of NPM1 is brought about by human SIRT1 and reduces its transcriptional activation potential. Remarkably, increased levels of acetylated NPM1 were found in grade II and III oral squamous cell carcinoma (OSCC) patient samples. Small interfering RNA (siRNA)-mediated knockdown of NPM1 in an OSCC cell line, followed by microarray analysis and chromatin immunoprecipitation experiments, revealed that some of the genes involved in oral cancer malignancy are regulated by NPM1 and have acetylated NPM1 localized at their promoters. Either suppression of p300 by siRNA or mutation of acetylatable lysine residues of NPM1 resulted in reduced occupancy of acetylated NPM1 on the target gene promoter concomitant with its decreased transcript levels. These observations suggest that acetylated NPM1 transcriptionally regulates genes involved in cell survival and proliferation during carcinogenesis.


Subject(s)
Cell Nucleus/metabolism , Gene Expression Regulation, Neoplastic , Genes, Neoplasm , Mouth Neoplasms/genetics , Nuclear Proteins/metabolism , Transcriptional Activation/genetics , Acetylation , Cell Line, Tumor , E1A-Associated p300 Protein/metabolism , Gene Knockdown Techniques , Humans , Mouth Neoplasms/enzymology , Mouth Neoplasms/pathology , Nucleophosmin , Promoter Regions, Genetic/genetics , Protein Transport , RNA Polymerase II/metabolism , Sirtuin 1 , Sirtuins/metabolism , Tumor Necrosis Factor-alpha/genetics
SELECTION OF CITATIONS
SEARCH DETAIL
...