59 research outputs found

    In Search of a Unified Theory: An Attempt to Reconcile Gravity and Quantum

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    Issues around geometry of the universe, density of the universe (Underweight), expansion of the universe and theories held-up by scientists such as Stephen Hawking, John Wheeler, Albert Einstein, etc have been looked into. The equations formulated by these people; that is E =mc2, E = hν and PV = nRT were treated to give meaning under the general truth that the universe has only two entities; MATTER and ENERGY and HEAT and COLD to manipulate them. The Energy x Time oMatter x Space relationships is suggested in this paper in place of, Energy.Matter = Space.Time, which was summarized by Albert Einstein. The three dimensionness of space were incorporated into E = mc2 to give E/N Ξ c3. E = hc/λo which had the notion of space divided by space is re-related to space per time and PV = nRT is revisited until it was modified to be in congruent with the above two fundamental formulations; that is PVΞ KT/N. These new relationships (THEORIES) are in agreement with each other and could be pronounced as “UNITED”

    The genomic landscape of 8-oxodG reveals enrichment at specific inherently fragile promoters

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    8-Oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) is the most common marker of oxidative stress and its accumulation within the genome has been associated with major human health issues such as cancer, aging, cardiovascular and neurodegenerative diseases. The characterization of the different genomic sites where 8-oxodG accumulates and the mechanisms underlying its formation are still poorly understood. Using OxiDIP-seq, we recently derived the genome-wide distribution of 8-oxodG in human non-tumorigenic epithelial breast cells (MCF10A). Here, we identify a subset of human promoters that accumulate 8-oxodG under steady-state condition. 8-oxodG nucleotides co-localize with double strand breaks (DSBs) at bidirectional and CG skewed promoters and their density correlate with RNA Polymerase II co-occupancy and transcription. Furthermore, by performing OxiDIP-seq in quiescent (G0) cells, we found a strong reduction of oxidatively-generated damage in the majority of 8-oxodG-positive promoters in the absence of DNA replication. Overall, our results suggest that the accumulation of 8-oxodG at gene promoters occurs through DNA replication-dependent or -independent mechanisms, with a possible contribution to the formation of cancer-associated translocation events

    Identification of Cdk8 and Cdkn2d as New Prame-Target Genes in 2C-like Embryonic Stem Cells

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    Embryonic stem cells (ESCs) present a characteristic pluripotency heterogeneity correspondent to specific metastates. We recently demonstrated that retinoic acid (RA) induces an increase in a specific 2C-like metastate marked by target genes specific to the two-cell embryo stage in preimplantation. Prame (Preferentially expressed antigen in melanoma) is one of the principal actors of the pluripotency stage with a specific role in RA responsiveness. Additionally, PRAME is overexpressed in a variety of cancers, but its molecular functions are poorly understood. To further investigate Prame’s downstream targets, we used a chromatin immunoprecipitation sequencing (ChIP-seq) assay in RA-enriched 2C-like metastates and identified two specific target genes, Cdk8 and Cdkn2d, bound by Prame. These two targets, involved in cancer dedifferentiation and pluripotency, have been further validated in RA-resistant ESCs. Here, we observed for the first time that Prame controls the Cdk8 and Cdkn2d genes in ESCs after RA treatment, shedding light on the regulatory network behind the establishment of naïve pluripotency

    Blastic plasmacytoid dendritic cell neoplasm: Genomics mark epigenetic dysregulation as a primary therapeutic target

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    Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy for which there is still no effective B therapy. In order to identify genetic alterations useful for a new treatment design, we used whole-exome sequencing to analyze 14 BPDCN patients and the patient-derived CAL-1 cell line. The functional enrichment analysis of mutational data reported the epigenetic regulatory program to be the most significantly undermined (P<0.0001). In particular, twenty-five epigenetic modifiers were found mutated (e.g. ASXL1, TET2, SUZ12, ARID1A, PHF2, CHD8); ASXL1 was the most frequently affected (28.6% of cases). To evaluate the impact of the identified epigenetic mutations at the gene-expression and Histone H3 lysine 27 trimethylation/acetylation levels, we performed additional RNA and pathology tissue-chromatin immunoprecipitation sequencing experiments. The patients displayed enrichment in gene signatures regulated by methylation and modifiable by decitabine administration, shared common H3K27-acetylated regions, and had a set of cell-cycle genes aberrantly up-regulated and marked by promoter acetylation. Collectively, the integration of sequencing data showed the potential of a therapy based on epigenetic agents. Through the adoption of a preclinical BPDCN mouse model, established by CAL-1 cell line xenografting, we demonstrated the efficacy of the combination of the epigenetic drugs 5’-azacytidine and decitabine in controlling disease progression in vivo

    Caffeine Prevents Transcription Inhibition and P-TEFb/7SK Dissociation Following UV-Induced DNA Damage

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    Background: The mechanisms by which DNA damage triggers suppression of transcription of a large number of genes are poorly understood. DNA damage rapidly induces a release of the positive transcription elongation factor b (P-TEFb) from the large inactive multisubunit 7SK snRNP complex. P-TEFb is required for transcription of most class II genes through stimulation of RNA polymerase II elongation and cotranscriptional pre-mRNA processing. Methodology/Principal Findings: We show here that caffeine prevents UV-induced dissociation of P-TEFb as well as transcription inhibition. The caffeine-effect does not involve PI3-kinase-related protein kinases, because inhibition of phosphatidylinositol 3-kinase family members (ATM, ATR and DNA-PK) neither prevents P-TEFb dissociation nor transcription inhibition. Finally, caffeine prevention of transcription inhibition is independent from DNA damage. Conclusion/Significance: Pharmacological prevention of P-TEFb/7SK snRNP dissociation and transcription inhibitio

    Blastic plasmacytoid dendritic cell neoplasm: genomics mark epigenetic dysregulation as a primary therapeutic target

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    Blastic Plasmacytoid Dendritic Cell Neoplasm is a rare and aggressive hematological malignancy currently lacking an effective therapy. To possibly identify genetic alterations useful for a new treatment design, we analyzed by whole-exome sequencing fourteen Blastic Plasmacytoid Dendritic Cell Neoplasm patients and the patient-derived CAL-1 cell line. The functional enrichment analysis of mutational data reported the epigenetic regulatory program as the most significantly undermined (P<.0001). In particular, twenty-five epigenetic-modifiers were found mutated (e.g., ASXL1, TET2, SUZ12, ARID1A, PHF2, CHD8); ASXL1 was the most frequently affected (28.6% of cases). To evaluate the impact of the identified epigenetic mutations at the gene-expression and Histone H3 lysine 27 trimethylation/acetylation levels, we performed additional RNA and Pathology tissue-chromatin immunoprecipitation sequencing experiments; the patients displayed enrichment in gene-signatures regulated by methylation and modifiable by Decitabine administration, shared common H3K27-acetylated regions and featured a set of cell-cycle genes aberrantly up-regulated and marked by promoter acetylation. Collectively, the integration of sequencing data showed the potential of a therapy based on epigenetic agents. Through the adoption of a preclinical Blastic Plasmacytoid Dendritic Cell Neoplasm mouse model, established by the CAL-1 cell line xenografting, we demonstrated the efficacy of the combination of the epigenetic drugs 5'-Azacytidine and Decitabine in controlling the disease progression in vivo

    Genetic polymorphisms associated with the inflammatory response in bacterial meningitis

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    BACKGROUND Bacterial meningitis (BM) is an infectious disease that results in high mortality and morbidity. Despite efficacious antibiotic therapy, neurological sequelae are often observed in patients after disease. Currently, the main challenge in BM treatment is to develop adjuvant therapies that reduce the occurrence of sequelae. In recent papers published by our group, we described the associations between the single nucleotide polymorphisms (SNPs) AADAT +401C > T, APEX1 Asn148Glu, OGG1 Ser326Cys and PARP1 Val762Ala and BM. In this study, we analyzed the associations between the SNPs TNF -308G > A, TNF -857C > T, IL-8 -251A > T and BM and investigated gene-gene interactions, including the SNPs that we published previously. METHODS The study was conducted with 54 BM patients and 110 healthy volunteers (as the control group). The genotypes were investigated via primer-introduced restriction analysis-polymerase chain reaction (PIRA-PCR) or polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analysis. Allelic and genotypic frequencies were also associated with cytokine and chemokine levels, as measured with the x-MAP method, and cell counts. We analyzed gene-gene interactions among SNPs using the generalized multifactor dimensionality reduction (GMDR) method. RESULTS We did not find significant association between the SNPs TNF -857C > T and IL-8 -251A > T and the disease. However, a higher frequency of the variant allele TNF -308A was observed in the control group, associated with changes in cytokine levels compared to individuals with wild type genotypes, suggesting a possible protective role. In addition, combined inter-gene interaction analysis indicated a significant association between certain genotypes and BM, mainly involving the alleles APEX1 148Glu, IL8 -251 T and AADAT +401 T. These genotypic combinations were shown to affect cyto/chemokine levels and cell counts in CSF samples from BM patients. CONCLUSIONS In conclusion, this study revealed a significant association between genetic variability and altered inflammatory responses, involving important pathways that are activated during BM. This knowledge may be useful for a better understanding of BM pathogenesis and the development of new therapeutic approaches

    KDM1A microenvironment, its oncogenic potential, and therapeutic significance

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    The lysine-specific histone demethylase 1A (KDM1A) was the first demethylase to challenge the concept of the irreversible nature of methylation marks. KDM1A, containing a flavin adenine dinucleotide (FAD)-dependent amine oxidase domain, demethylates histone 3 lysine 4 and histone 3 lysine 9 (H3K4me1/2 and H3K9me1/2). It has emerged as an epigenetic developmental regulator and was shown to be involved in carcinogenesis. The functional diversity of KDM1A originates from its complex structure and interactions with transcription factors, promoters, enhancers, oncoproteins, and tumor-associated genes (tumor suppressors and activators). In this review, we discuss the microenvironment of KDM1A in cancer progression that enables this protein to activate or repress target gene expression, thus making it an important epigenetic modifier that regulates the growth and differentiation potential of cells. A detailed analysis of the mechanisms underlying the interactions between KDM1A and the associated complexes will help to improve our understanding of epigenetic regulation, which may enable the discovery of more effective anticancer drugs

    SUMO-activating SAE1 transcription is positively regulated by Myc

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    Myc protein plays a fundamental role in regulation of cell cycle, proliferation, differentiation and apoptosis by modulating the expression of a large number of targets. Here we report the transactivation ability of the human Myc protein to activate the SUMO-activating enzyme SAE1 transcription. We found that Myc activates SAE1 transcrip- tion via direct binding to canonical E-Boxes sequences located close to the SAE1 transcription start site. A recent report has highlighted the crucial role of the SAE gene expression in Myc mediated oncogenesis. Our study adds new insight in this context since we show here that Myc directly activates SAE1 transcription, suggesting that Myc onco- genic activity which depends on SAE1 is ensured by Myc itself through direct binding and transcriptional activation of SAE1 expression
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