Tyrosine dephosphorylation of H2AX modulates apoptosis and survival decisions.

Life and death fate decisions allow cells to avoid massive apoptotic death in response to genotoxic stress. Although the regulatory mechanisms and signalling pathways controlling DNA repair and apoptosis are well characterized, the precise molecular strategies that determine the ultimate choice of DNA repair and survival or apoptotic cell death remain incompletely understood. Here we report that a protein tyrosine phosphatase, EYA, is involved in promoting efficient DNA repair rather than apoptosis in response to genotoxic stress in mammalian embryonic kidney cells by executing a damage-signal-dependent dephosphorylation of an H2AX carboxy-terminal tyrosine phosphate (Y142). This post-translational modification determines the relative recruitment of either DNA repair or pro-apoptotic factors to the tail of serine phosphorylated histone H2AX (gamma-H2AX) and allows it to function as an active determinant of repair/survival versus apoptotic responses to DNA damage, revealing an additional phosphorylation-dependent mechanism that modulates survival/apoptotic decisions during mammalian organogenesis

Jmjd6a regulates GSK3β RNA splicing in Xenopus laevis eye development.

It has been suggested that Jmjd6 plays an important role in gene regulation through its demethylation or hydroxylation activity on histone and transcription factors. In addition, Jmjd6 has been shown to regulate RNA splicing by interaction with splicing factors. In this study, we demonstrated that Jmjd6a is expressed in developing Xenopus laevis eye during optic vesicle formation and retinal layer differentiation stages. Knockdown of Jmjd6a by an antisense morpholino resulted in eye malformation including a deformed retinal layer and no lens formation. We further found down-regulation of gene expression related to eye development such as Rx1, Otx2, and Pax6 in Jmjd6a morpholino injected embryos. Jmjd6 interacts with splicing factor U2AF25 and GSK3β RNA in the anterior region of Xenopus embryos. Knockdown of Jmjd6a led to deletion of GSK3β RNA exon 1 and 2, which resulted in generation of N'-terminal truncated GSK3β protein. This event further caused decreased phosphorylation of β-catenin and subsequently increased β-catenin stability. Therefore, our result may suggest that Jmjd6a plays an important role in Xenopus eye development through regulation of GSK3β RNA splicing and canonical Wnt/β-catenin signaling

Ghrelin Represses Thymic Stromal Lymphopoietin Gene Expression through Activation of Glucocorticoid Receptor and Protein Kinase C Delta in Inflamed Skin Keratinocytes

Ghrelin, a peptide hormone secreted from enteroendocrine cells of the gastrointestinal tract, has anti-inflammatory activity in skin diseases, including dermatitis and psoriasis. However, the molecular mechanism underlying the beneficial effect of ghrelin on skin inflammation is not clear. In this study, we found that ghrelin alleviates atopic dermatitis (AD)-phenotypes through suppression of thymic stromal lymphopoietin (TSLP) gene activation. Knockdown or antagonist treatment of growth hormone secretagogue receptor 1a (GHSR1a), the receptor for ghrelin, suppressed ghrelin-induced alleviation of AD-like phenotypes and suppression of TSLP gene activation. We further found that ghrelin induces activation of the glucocorticoid receptor (GR), leading to the binding of GR with histone deacetylase 3 (HDAC3) and nuclear receptor corepressor (NCoR) NCoR corepressor to negative glucocorticoid response element (nGRE) on the TSLP gene promoter. In addition, ghrelin-induced protein kinase C δ (PKCδ)-mediated phosphorylation of p300 at serine 89 (S89), which decreased the acetylation and DNA binding activity of nuclear factor- κB (NF-κB) p65 to the TSLP gene promoter. Knockdown of PKCδ abolished ghrelin-induced suppression of TSLP gene activation. Our study suggests that ghrelin may help to reduce skin inflammation through GR and PKCδ-p300-NF-κB-mediated suppression of TSLP gene activation

The Clinical Features and Emotional Stressors in Korean Patients with Tako-Tsubo Cardiomyopathy

Background. Tako-tsubo cardiomyopathy (TTC) is typically triggered by an acute emotional or physical stress events. Aim of this study was to investigate the impact of emotional stressors on clinical features, laboratory parameters, electrocardiographic and echocardiographic findings in patients with TTC. Methods. Of 103 patients enrolled from the TTC registry database, fifteen patients had emotional triggers (E group), and 88 patients had physical triggers or no triggers (other group). Results. Most clinical presentations and in-hospital courses were similar between the groups. However, E group had higher prevalence of chest pain (87 versus 42 %, P=0.001), palpitation (27 versus 6%, P=0.008), whereas other group had higher prevalence of cardiogenic shock (35 versus 7%, P=0.027). E group had significantly higher corrected QT intervals (median, 477.5 versus 438 ms, P=0.001), and left ventricular ejection fraction (LVEF) (mean, 45.7 versus 39.6%, P=0.001), but lower hs-CRP (median, 0.1 versus 3.3 mg/L, P=0.001), CK-MB (median, 5.5 versus 11.9 ng/mL, P=0.047), troponin-I (median, 1.0 versus 3.2 ng/mL, P=0.011), and NT-proBNP levels (median, 2145 versus 4939 pg/mL, P=0.020). Other group required more frequent hemodynamic support and had significantly longer intensive care unit (median, 3 versus 1 days, P=0.005) and in-hospital (median, 17 versus 3 days, P=0.001) durations. Conclusion. The clinical features of TTC are different between groups with and without preceding emotional stressors. The TTC group with preceding emotional stressors was more likely to have preserved cardiovascular reserve and lesser likely to require hemodynamic support than other group although the entire prognosis of TTC is excellent regardless of triggering stressors

Tyrosine dephosphorylation of H2AX modulates apoptosis and survival decisions.

Life and death fate decisions allow cells to avoid massive apoptotic death in response to genotoxic stress. Although the regulatory mechanisms and signalling pathways controlling DNA repair and apoptosis are well characterized, the precise molecular strategies that determine the ultimate choice of DNA repair and survival or apoptotic cell death remain incompletely understood. Here we report that a protein tyrosine phosphatase, EYA, is involved in promoting efficient DNA repair rather than apoptosis in response to genotoxic stress in mammalian embryonic kidney cells by executing a damage-signal-dependent dephosphorylation of an H2AX carboxy-terminal tyrosine phosphate (Y142). This post-translational modification determines the relative recruitment of either DNA repair or pro-apoptotic factors to the tail of serine phosphorylated histone H2AX (gamma-H2AX) and allows it to function as an active determinant of repair/survival versus apoptotic responses to DNA damage, revealing an additional phosphorylation-dependent mechanism that modulates survival/apoptotic decisions during mammalian organogenesis

Regulation of XFGF8 gene expression through SRY (sex-determining region Y)-box 2 in developing Xenopus embryos.

Fibroblast growth factors (FGFs) function as mitogens and morphogens during vertebrate development. In the present study, to characterise the regulatory mechanism of FGF8 gene expression in developing Xenopus embryos the upstream region of the Xenopus FGF8 (XFGF8) gene was isolated. The upstream region of the XFGF8 gene contains two putative binding sites for the SRY (sex-determining region Y)-box 2 (SOX2) transcription factor. A reporter assay with serially deleted constructs revealed that the putative SOX2-binding motif may be a critical cis-element for XFGF8 gene activation in developing Xenopus embryos. Furthermore, Xenopus SOX2 (XSOX2) physically interacted with the SOX2-binding motif within the upstream region of the XFGF8 gene in vitro and in vivo. Depletion of endogenous XSOX2 resulted in loss of XFGF8 gene expression in midbrain-hindbrain junction, auditory placode, lens placode and forebrain in developing Xenopus embryos. Collectively, our results suggest that XSOX2 directly upregulates XFGF8 gene expression in the early embryonic development of Xenopus

Clinical features in adult patients with in-hospital cardiovascular events with confirmed 2009 Influenza A (H1N1) virus infection: Comparison with those without in-hospital cardiovascular events

Background: Comprehensive data regarding in-hospital cardiovascular events of adults with confirmed 2009 influenza A (H1N1) (2009 H1N1) infections are limited. The aim of this study was to determine the clinical characteristics, laboratory parameters, and electrocardiographic (ECG) findings for adults with 2009 H1N1 infections and to assess the differences in these parameters among adult patients with and without in-hospital cardiovascular events. Methods: Seventy-one patients were enrolled from the 2009 H1N1 registry database (our hospital registry of confirmed 2009 H1N1 infection during the year 2009) and divided according to the presence of in-hospital cardiovascular events. Six patients had cardiovascular events (CV group) and 65 did not (NCV group). Results: The CV group was more likely to be old (p = 0.023). Regarding co-morbidities, underlying coronary heart disease (p = 0.001), congestive heart failure (p = 0.001), diabetes (p = 0.001), and hypertension (p = 0.014) had significant influences on cardiovascular events. The CV group was also more likely to have chest pain (p = 0.034), dyspnea (p = 0.045), higher leukocyte count (p = 0.014), higher C-reactive protein (p = 0.010), higher glucose level (p = 0.001), and higher N-terminal probrain natriuretic peptide level (p = 0.010) than the NCV group. In addition, the CV group had a significantly higher in-hospital mortality rate (p = 0.010) and cardiac mortality rate (p = 0.001) than the NCV group. However, there were no significant differences in ECG findings between the two groups. Conclusion: Our study demonstrated that the CV group had higher in-hospital and cardiac mortality rates than the NCV group. A meticulous therapeutic approach should be considered for elderly patients with 2009 H1N1 infections having coronary heart disease, congestive heart failure, diabetes, hypertension, and high levels of leukocyte count, hs-CRP, glucose, and NT-proBNP at the time of admission

SFMBT2-Mediated Infiltration of Preadipocytes and TAMs in Prostate Cancer

Infiltration of diverse cell types into tumor microenvironment plays a critical role in cancer progression including metastasis. We previously reported that SFMBT2 (Scm-like with four mbt domains 2) regulates the expression of matrix metalloproteinases (MMPs) and migration and invasion of cancer cells in prostate cancer. Here we investigated whether the down-regulation of SFMBT2 regulates the infiltration of preadipocytes and tumor-associated macrophages (TAMs) in prostate cancer. We found that the down-regulation of SFMBT2 promotes the infiltration of preadipocytes and TAMs through up-regulation of CXCL8, CCL2, CXCL10, and CCL20 expression in prostate cancer. Expression of CXCL8, CCL2, CXCL10, and CCL20 was also elevated in prostate cancer patients having a higher Gleason score (≥8), which had substantially lower SFMBT2 expression. We also found that the up-regulation of CXCL8, CCL2, CXCL10, and CCL20 expression is dependent on NF-κB activation in prostate cancer cells expressing a low level of SFMBT2. Moreover, increased IL-6 from infiltrated preadipocytes and TAMs promoted migration and invasion of prostate cancer cells expressing a low level of SFMBT2. Our study may suggest that SFMBT2 a critical regulator for the infiltration of preadipocytes and TAMs into the prostate tumor microenvironment. Thus, the regulation of SFMBT2 may provide a new therapeutic strategy to inhibit prostate cancer metastasis, and SFMBT2 could be used as a potential biomarker in prostate cancer metastasis