Purpose
To identify the perceived level of lung cancer stigma, resilience, and happiness among advanced lung cancer patients during treatment, and to analyze the mediating effect of resilience in the ...relationship between stigma and happiness.
Methods
A cross-sectional study design was used. A total of 184 patients diagnosed with advanced lung cancer were recruited from the National Cancer Center in Korea. Lung cancer stigma, resilience, and happiness were measured using questionnaires.
Results
Findings indicate that whereas lung cancer stigma had a negative correlation with resilience and happiness, resilience had a positive correlation with happiness. There was a significant indirect effect of stigma on happiness through resilience, indicating a mediating effect of resilience.
Conclusions
The results make significant contributions, like the importance of encouraging patients with non-judgmental approach, to clinical practices related to happiness of individuals with advanced cancer. It suggests that the stigma of advanced lung cancer patient can be overcome with enough resilience, and patients may experience happiness during treatment.
Human pluripotent stem cell (hPSC)-derived intestinal organoids (hIOs) form 3D structures organized into crypt and villus domains, making them an excellent in vitro model system for studying human ...intestinal development and disease. However, hPSC-derived hIOs still require in vivo maturation to fully recapitulate adult intestine, with the mechanism of maturation remaining elusive. Here, we show that the co-culture with human T lymphocytes induce the in vitro maturation of hIOs, and identify STAT3-activating interleukin-2 (IL-2) as the major factor inducing maturation. hIOs exposed to IL-2 closely mimic the adult intestinal epithelium and have comparable expression levels of mature intestinal markers, as well as increased intestine-specific functional activities. Even after in vivo engraftment, in vitro-matured hIOs retain their maturation status. The results of our study demonstrate that STAT3 signaling can induce the maturation of hIOs in vitro, thereby circumventing the need for animal models and in vivo maturation.
In mammals, RNA interference is primarily a post-transcriptional mechanism. Evidence has accumulated for additional role in transcriptional gene silencing (TGS) but the question for a good paradigm ...for small interfering antigene RNA (agRNA)-induced chromatin modification remains unanswered. Here, we show that SETDB1, a histone H3-lysine 9 (H3K9)-specific methyltransferase, cooperates with Argonaute-2 (AGO2) and plays an essential role in agRNA-induced TGS. The androgen receptor (AR) gene was transcriptionally silenced by agRNA targeted to its promoter, and we show that this repression was mitigated by knockdown of SETDB1 or AGO2. Chromatin immunoprecipitation demonstrated that agRNA-driven AGO2 was first targeted to the AR promoter, followed by SETDB1. SIN3A and HDAC1/2, the components of the SIN3-HDAC complex, immunoprecipitated with SETDB1, and localized at the agRNA-targeted promoter. Agreeing with the presence of SETDB1, trimethyl-H3K9 was enriched in the AR promoter. Both EZH2 and trimethyl-H3K27 were also present in the targeted locus; accordingly, EZH2 immunoprecipitated with SETDB1. DNA methylation level was not significantly changed, suggesting the absence of de novo methylating activity in agRNA-induced AR promoter. Our results demonstrate that SETDB1, together with AGO2, plays an essential role in TGS through recruiting chromatin remodeler and/or other modifiers, consequently creating a repressive chromatin milieu at the targeted promoter.
Regulated nuclear entry of over‐expressed Setdb1 Cho, Sunwha; Park, Jung Sun; Kang, Yong‐Kook
Genes to cells : devoted to molecular & cellular mechanisms,
August 2013, Letnik:
18, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Setdb1 is a histone H3‐lysine 9 (H3K9)‐specific methyltransferase that interacts with various transcriptional regulators to induce local heterochromatin formation and participates as an indispensable ...component in building promyelocytic leukemia nuclear body (PML‐NB), which is involved in various biological processes. We studied the effects of Setdb1 over‐expression. We unexpectedly observed that exogenously expressed GFP‐Setdb1 was retained in the cytoplasm, whereas endogenous Setdb1 showed a punctate nuclear signal. Leptomycin B (LMB) treatment, which blocks protein export from the nucleus, showed that entry of GFP‐Setdb1 to the nucleus was regulated and that GFP‐Setdb1 in the nucleus could localize at PML‐NB as endogenous Setdb1. An analysis of Setdb1 deletion constructs showed that the N‐terminal region was related to the nuclear export of Setdb1; supporting this, we detected two nuclear export signal motifs in this region. This N‐terminal region had a SUMO interaction motif (SIM) whose mutation greatly reduced the ability of Setdb1 to associate with PML‐NB and thus resulted in the disaggregation of PML‐NB structure. We therefore presume that the cytoplasmic retention of over‐expressed Setdb1 occurs as part of a regulatory mechanism to set a tight limit on the nuclear activity of Setdb1, whose excess activity might result in random and haphazard chromatin modifications that cause globally aberrant gene expression.
The diagnosis of Parkinson's disease (PD) is initiated after the occurrence of motor symptoms, such as resting tremors, rigidity, and bradykinesia. According to previous reports, non-motor symptoms, ...notably gastrointestinal dysfunction, could potentially be early biomarkers in PD patients as such symptoms occur earlier than motor symptoms. However, connecting PD to the intestine is methodologically challenging. Thus, we generated in vitro human intestinal organoids from PD patients and ex vivo mouse small intestinal organoids from aged transgenic mice. Both intestinal organoids (IOs) contained the human
G2019S mutation, which is the most frequent genetic cause of familial and sporadic PD. By conducting comprehensive genomic comparisons with these two types of IOs, we determined that a particular gene, namely, Iroquois homeobox protein 2 (
), showed PD-related expression patterns not only in human pluripotent stem cell (PSC)-derived neuroectodermal spheres but also in human PSC-derived neuronal cells containing dopaminergic neurons. We expected that our approach of using various cell types presented a novel technical method for studying the effects of multi-organs in PD pathophysiology as well as for the development of diagnostic markers for PD.
Studies have provided important findings about the roles of Notch signaling in neural development. Unfortunately, however, most of these studies have investigated the neural stem cells (NSCs) of mice ...or other laboratory animals rather than humans, mainly owing to the difficulties associated with obtaining human brain samples. It prompted us to focus on neuroectodermal spheres (NESs) which are derived from human embryonic stem cell (hESC) and densely inhabited by NSCs. We here investigated the role of Notch signaling with the hESC-derived NESs.
From hESCs, we derived NESs, the in-vitro version of brain-derived neurospheres. NES formation was confirmed by increased levels of various NSC marker genes and the emergence of rosette structures in which neuroprogenitors are known to reside. We found that Notch signaling, which maintains stem cell characteristics of in-vivo-derived neuroprogenitors, is active in these hESC-derived NESs, similar to their in-vivo counterpart. Expression levels of Notch signaling molecules such as NICD, DLLs, JAG1, HES1 and HES5 were increased in the NESs. Inhibition of the Notch signaling by a gamma-secretase inhibitor reduced rosette structures, expression levels of NSC marker genes and proliferation potential in the NESs, and, if combined with withdrawal of growth factors, triggered differentiation toward neurons.
Our results indicate that the hESC-derived NESs, which share biochemical features with brain-derived neurospheres, maintain stem cell characteristics mainly through Notch signaling, which suggests that the hESC-derived NESs could be an in-vitro model for in-vivo neurogenesis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Setdb1/Eset is a histone H3 lysine 9 (H3K9)-specific methyltransferase that associates with various transcription factors to regulate gene expression via chromatin remodeling. Here, we report that ...Setdb1 associates with promyelocytic leukemia (Pml) protein from the early stage of mouse development and is a constitutive member of promyelocytic leukemia (PML)-nuclear bodies (PML-NBs) that have been linked to many cellular processes such as apoptosis, DNA damage responses, and transcriptional regulation. Arsenic treatment, which induces Pml degradation, caused Setdb1 signals to disappear. Setdb1 knockdown resulted in dismantlement of PML-NBs. Immunoprecipitation results demonstrated physical interactions between Setdb1 and Pml. Chromatin immunoprecipitation revealed that, within the frame of PML-NBs, Setdb1 binds the promoter of Id2 and suppresses its expression through installing H3K9 methylation. Our findings suggest that Setdb1 performs dual, but inseparable, functions at PML-NBs to maintain the structural integrity of PML-NBs and to control PML-NB-associated genes transcriptionally.
Background: Setdb1 regulates gene expression with various transcription factors.
Results: Setdb1 is a constitutive member of PML-NB and suppresses Id2 expression.
Conclusion: Setdb1 maintains PML-NB structure and concurrently controls PML-NB-associated genes.
Significance: This provides the mechanism of Setdb1 being involved in PML-mediated transcriptional regulation.
Epigenetic reprogramming is necessary in somatic cell nuclear transfer (SCNT) embryos in order to erase the differentiation-associated epigenetic marks of donor cells. However, such epigenetic ...memories often persist throughout the course of clonal development, thus decreasing cloning efficiency. Here, we explored reprogramming-refractory regions in bovine SCNT blastocyst transcriptomes. We observed that histone genes residing in the 1.5 Mb spanning the cow HIST1 cluster were coordinately downregulated in SCNT blastocysts. In contrast, both the nonhistone genes of this cluster, and histone genes elsewhere remained unaffected. This indicated that the downregulation was specific to HIST1 histone genes. We found that, after trichostatin A treatment, HIST1 histone genes were derepressed, and DNA methylation at their promoters was decreased to the level of in vitro fertilization embryos. Therefore, our results indicate that the reduced expression of HIST1 histone genes is a consequence of poor epigenetic reprogramming in SCNT blastocysts.
Post-translational modifications of histones play important roles in regulating chromatin dynamics and epigenetic inheritance during mitosis. The epigenetic significance and stability of histone ...H3-lysine 9 (H3K9) modifications have been well studied in interphase cells, whereas not as much in mitotic cells. Here, we inspected mitosis-coupled alterations in the global modifications of H3K9. Signals for H3K9 mono-, di-methylation and acetylation became invisible as cells entered mitosis in contrast to the pattern observed for H3-serine 10 phosphorylation (H3S10ph). Treatment with the aurora-B inhibitor ZM447439 or expression of the dominant negative mutant Aur-BK¹⁰⁶R resulted in prometaphase chromosomes that lacked signals for H3S10ph but were positive for H3K9 modifications. Trimethylation was the sole K9 modification that remained consistently detectable throughout the cell cycle. This phenomenon was specific for H3K9-S10, as this pattern was not observed at H3K27-S28. Methylated H3K27 remained detectable throughout the cell cycle, despite phosphorylation of the adjacent H3S28. Contrastingly, our dot-blot experiment using synthetic peptides showed that phosphorylation of serine residue basically kept adjacent lysine from antibody access. Together, these results suggest that phosphorylation of serine residue occurs in a selective manner, being influenced by the types of modifications and the nature of neighboring lysine residues.
Early mammalian embryos are thought to gain nuclear totipotency through DNA methylation reprogramming (DMR). By this process, DNA methylation patterns acquired during gametogenesis that are ...unnecessary for zygotic development are erased. The DMR patterns of various mammalian species have been studied; however, they do not seem to have a conserved pattern. We examined early goat embryos to find conforming rules underlying mammalian DMR patterns. Immunocytochemical results showed that the overall level of DNA methylation was not greatly changed during the pronucleus stage. At the two-cell stage, active demethylation occurred and simultaneously affected both parental DNAs, resulting in a global loss of 5-methylcytosine. The level of DNA methylation was lowest in the four-cell stage, with increased de novo methylation during the eight-cell stage. Histone H3-lysine 9 was gradually trimethylated in the sperm-derived chromatin, continuing from the pronucleus stage through the two-cell stage. This goat DMR pattern is novel and distinct from the DMRs of other mammalian species. The more mammalian species we included for DMR analysis, the more multifarious patterns we obtained, adding an extra diversity each time to the known mammalian DMR patterns. Nevertheless, the evolutionary significance and developmental consequence of such diverse DMR patterns are currently unknown.
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