C-terminus of the Sgf73 subunit of SAGA and SLIK is important for retention in the larger complex and for heterochromatin boundary function.

The budding yeast Saccharomyces cerevisiae contains active and inactive chromatin separated by boundary domains. Previously, we used genome-wide screening to identify 55 boundary-related genes. Here, we focus on Sgf73, a boundary protein that is a component of the Spt-Ada-Gcn5 acetyltransferase (SAGA) and SLIK (SAGA-like) complexes. These complexes have histone acetyltransferase (HAT) and histone deubiquitinase activity, and Sgf73 is one of the factors necessary to anchor the deubiquitination module. Domain analysis of Sgf73 was carried out, and the minimum region (373-402 aa) essential for boundary function was identified. This minimum region does not include the domain involved in anchoring the deubiquitination module, suggesting that the histone deubiquitinase activity of Sgf73 is not important for its boundary function. Next, Sgf73-mediated boundary function was analyzed in disruption strains in which different protein subunits of the SAGA/SLIK/ADA complexes were deleted. Deletion of ada2, ada3 or gcn5 (a HAT module component) caused complete loss of the boundary function of Sgf73. The importance of SAGA or SLIK complex binding to the boundary function of Sgf73 was also analyzed. Western blot analysis detected both the full-length and truncated forms of Spt7, suggesting that SAGA and SLIK complex formation is important for the boundary function of Sgf73.

Management of extremely low birth weight neonates with bowel obstruction within 2 weeks after birth.

PURPOSE: The majority of bowel obstructions in extremely low birth weight (ELBW) neonates are meconium-related ileus (MRI). ELBW neonates with bowel obstruction may recover by conservative treatment, but some do not. Considering the high surgical morbidity rates, unnecessary surgery should be avoided. We sought to identify a reasonable treatment strategy under these conditions. METHODS: ELBW neonates who started to have bowel obstruction with an unclear cause within 14 days of age were enrolled. The study period was from January 2009 to August 2011. The enrolled patients had daily Gastrografin(®) enemas until 14 days of age or until the obstruction resolved. If the obstruction lasted beyond around 14 days of age, the patient underwent surgical intervention. The clinical data of the patients were collected and analyzed. RESULTS: Fourteen patients were enrolled. Twelve patients had MRI, which resolved within 14 days without surgery. Two patients with persistent obstruction underwent surgery, and they were found to have Hirschsprung's disease and ileal volvulus, respectively. CONCLUSION: For ELBW neonates with bowel obstruction of unclear etiology, the early and frequent administration of a Gastrografin(®) enema is reasonable. Surgery should be considered if the obstruction lasts beyond approximately 14 days after birth.

Multimodal Imaging of a Severe Case of Neonatal Acute Retinal Necrosis and Lens Vacuoles Associated with Herpes Simplex Virus Infection.

PURPOSE: To report a case of a neonate with acute retinal necrosis, lens vacuoles, and encephalitis associated with herpes simplex virus (HSV) infection. DESIGN: Case report. METHODS: Retrospective chart review. RESULTS: A male neonate was brought for screening for retinopathy of prematurity at the corrected age of 32 weeks. Slit-lamp examination showed lens vacuoles in both eyes. Fundus examination revealed extensive retinal detachments with prominent retinal whitening, subretinal exudates, and retinal hemorrhage. Computed tomography of the brain showed encephalomalacia. Polymerase chain reaction of cerebrospinal fluid and anterior chamber fluid was both positive for HSV-1. Despite systemic anti-viral therapy, a rhegmatogenous retinal detachment and subsequent proliferative vitreoretinopathy developed in the patient's right eye. The retinal detachment in the left eye resolved, but significant chorioretinal degeneration occurred. With time lens vacuoles decreased in number. CONCLUSIONS: Clinicians should remember this rare, but devastating condition without specific prodromal symptoms.

Visual Outcome and Treatment Frequency of Anti-VEGF Therapy Using the Treat-and-Extend and Treatment Cessation Regimen for Exudative Age-Related Macular Degeneration and Pachychoroid Neovasculopathy.

PURPOSE: To report the results of anti-vascular endothelial growth factor (VEGF) therapy using treat-and-extend (TAE) and treatment cessation regimens for exudative age-related macular degeneration (AMD) and pachychoroid neovasculopathy (PN). METHODS: We retrospectively studied 101 treatment-naïve eyes of 101 patients with exudative AMD and PN that underwent anti-VEGF therapy using TAE and treatment cessation regimen with a follow-up period of ≥12 months. Best-corrected visual acuity (BCVA), treatment frequency, and number of eyes with successful treatment cessation were measured. Successful treatment cessation was defined as dry macula retention without treatment for >16 weeks after the last injections. Factors related to the successful treatment cessation were evaluated. RESULTS: BCVA was maintained at the last visit with a mean follow-up period of 49.9 ± 26.9 months. The injection number decreased from 6.8 ± 2.31 at the first year to 3.7 ± 3.64 at the fifth year. At the last visit, 48 (47.5%) eyes were being treated at an interval of ≥12 weeks or were under treatment cessation. Successful treatment cessation during the follow-up period and at the last visit were achieved in 56 (55.4%) and 27 (26.7%) eyes, with a median treatment-free period of 66 and 126 weeks, respectively. Good early treatment response and a small recurrence number were associated with successful treatment cessation at the last visit. CONCLUSION: Patients with good early response to treatment and fewer recurrences may achieve treatment cessation. This information could help physicians predict the achievement of treatment cessation for a considerable period.

Systemic and Ocular Determinants of Choroidal Structures on Optical Coherence Tomography of Eyes with Diabetes and Diabetic Retinopathy.

Knowledgeof the choroidal structures in eyes with diabetes and diabetic retinopathy (DR) should provide information on the pathogenesis of DR. A prospective study was performed to determine the systemic and ocular factors that affect the choroidal structures in eyes with diabetes. Two-hundred consecutive diabetic subjects consisted of 160 treatment-naïve patients with different stages of DR and 40 patients with proliferative DR with prior panretinal photocoagulation (PRP). All underwent blood and urine tests and enhanced depth imaging optical coherence tomography (EDI-OCT). The cross-sectional EDI-OCT images of the subfoveal choroid were binarized to measure the total choroidal area (TCA), luminal area, and stromal area. Multivariate regression analyses were performed to determine the systemic and ocular factors that were significantly correlated with the choroidal structures. The subfoveal choroidal thickness, TCA, luminal area, and stromal area were larger at more advanced stage of DR, and smaller in eyes with PRP than those without (P < 0.001). The TCA and stromal area were significantly and positively correlated with the degree of albuminuria (P = 0.034, P = 0.025, respectively). The choroidal lumen and stroma may increase as the stages of DR progress and decrease after PRP. Albuminuria may be associated with the choroidal stromal edema.

Cloning and expression of three formate oxidase genes from Debaryomyces vanrijiae MH201.

Debaryomyces vanrijiae MH201 produces formate oxidase (FOD) at estimated pI values by native isoelectric focusing of 5.1, 5.4, and 5.9. We cloned and expressed three formate oxidase cDNAs, FOD1, FOD2, and FDO3, of the yeast using Escherichia coli. The open reading frames of FOD1, FOD2, and FDO3 were 1,731 bp long, and encoded 576-amino acid polypeptides with molecular masses of 64,142, 63,794, and 63,836 Da respectively. Expression of FOD1, FOD2, and FOD3 resulted in the production of three isozymes, with pI values of 5.1, 5.9, and 5.9 respectively. Co-expression of FOD1 and FOD2 and of FOD1 and FOD3 resulted in the production of additional isozymes with pI values, of 5.4. The three amino acid sequences of FOD1, FOD2, and FOD3 contained a consensus motif of a flavin adenine dinucleotide binding site in their N-terminal parts and a glucose-methanol-choline oxidoreductase signature pattern, suggesting that formate oxidase ought to be classified in the glucose-methanol-choline oxidoreductase family.

Identification of novel suppressors for Mog1 implies its involvement in RNA metabolism, lipid metabolism and signal transduction.

Mog1 is conserved from yeast to mammal, but its function is obscure. We isolated yeast genes that rescued a temperature-sensitive death of S. cerevisiae Scmog1Delta, and of S. pombe Spmog1(ts). Scmog1Delta was rescued by Opi3p, a phospholipid N-methyltransferase, in addition to S. cerevisiae Ran-homologue Gsp1p, and a RanGDP binding protein Ntf2p. On the other hand, Spmog1(ts) was rescued by Cid13 that is a poly (A) polymerase specific for suc22(+) mRNA encoding a subunit of ribonucleotide reductase, Ssp1 that is a protein kinase involved in stress response pathway, and Crp79 that is required for mRNA export, in addition to Spi1, S. pombe Ran-homologue, and Nxt2, S. pombe homologue of Ntf2p. Consistent with the identification of those suppressors, lack of ScMog1p dislocates Opi3p from the nuclear membrane and all of Spmog1(ts) showed the nuclear accumulation of mRNA. Furthermore, SpMog1 was co-precipitated with Nxt2 and Cid13.

LATS2 Positively Regulates Polycomb Repressive Complex 2.

LATS2, a pivotal Ser/Thr kinase of the Hippo pathway, plays important roles in many biological processes. LATS2 also function in Hippo-independent pathway, including mitosis, DNA damage response and epithelial to mesenchymal transition. However, the physiological relevance and molecular basis of these LATS2 functions remain obscure. To understand novel functions of LATS2, we constructed a LATS2 knockout HeLa-S3 cell line using TAL-effector nuclease (TALEN). Integrated omics profiling of this cell line revealed that LATS2 knockout caused genome-wide downregulation of Polycomb repressive complex 2 (PRC2) and H3K27me3. Cell-cycle analysis revealed that downregulation of PRC2 was not due to cell cycle aberrations caused by LATS2 knockout. Not LATS1, a homolog of LATS2, but LATS2 bound PRC2 on chromatin and phosphorylated it. LATS2 positively regulates histone methyltransferase activity of PRC2 and their expression at both the mRNA and protein levels. Our findings reveal a novel signal upstream of PRC2, and provide insight into the crucial role of LATS2 in coordinating the epigenome through regulation of PRC2.

Histone Deacetylase Inhibition in Prostate Cancer Triggers miR-320-Mediated Suppression of the Androgen Receptor.

Targeting androgen receptor (AR) by pharmacologic intervention is one of the effective approaches for treatment of malignant prostate cancers. Histone deacetylase (HDAC) alters the epigenetic status of tumor-associated genes, including those for miRNAs (miRNA), and affects the behavior of cancers. Here, we examined the molecular effects of a HDAC inhibitor, OBP-801, on AR expression and tumor cell growth in prostate cancers. Treatment with OBP-801 efficiently suppressed cell growth of three prostate cancer lines (22Rv1, VCaP, and LNCaP), together with AR downregulation, regardless of their hormone sensitivity. Intriguingly, this effect by OBP-801 was not due to decreased transcriptional activity of the AR gene, but due to posttranscriptional regulation, namely by miRNA-mediated suppression. Among the upregulated miRNAs after OBP-801 treatment in the three prostate cancer cell lines, miR-320a, whose expression was significantly correlated with prognosis of prostate cancers (P = 0.0185), was the most closely associated with AR expression. An miR-320a mimic suppressed AR protein expression together with growth suppression, while anti-miR-320a oligonucleotide significantly abrogated the growth suppression by OBP-801 treatment. FISH analysis revealed that miR-320a was highly expressed in human normal prostate luminal cells, but was rarely expressed in prostate cancer cells. In an AR-dependent prostate tumorigenic rat model, OBP-801 treatment profoundly increased miR-320a expression and repressed prostate tumorigenesis. Our data demonstrated that OBP-801 effectively suppressed AR activity via epigenetic upregulation of miR-320a, which resulted in tumor cell growth suppression of prostate cancers. OBP-801 may be a potent AR-targeting therapeutic reagent in AR-positive prostate cancer regardless of androgen dependency. Cancer Res; 76(14); 4192-204. ©2016 AACR.

Targeting the Notch-regulated non-coding RNA TUG1 for glioma treatment.

Targeting self-renewal is an important goal in cancer therapy and recent studies have focused on Notch signalling in the maintenance of stemness of glioma stem cells (GSCs). Understanding cancer-specific Notch regulation would improve specificity of targeting this pathway. In this study, we find that Notch1 activation in GSCs specifically induces expression of the lncRNA, TUG1. TUG1 coordinately promotes self-renewal by sponging miR-145 in the cytoplasm and recruiting polycomb to repress differentiation genes by locus-specific methylation of histone H3K27 via YY1-binding activity in the nucleus. Furthermore, intravenous treatment with antisense oligonucleotides targeting TUG1 coupled with a drug delivery system induces GSC differentiation and efficiently represses GSC growth in vivo. Our results highlight the importance of the Notch-lncRNA axis in regulating self-renewal of glioma cells and provide a strong rationale for targeting TUG1 as a specific and potent therapeutic approach to eliminate the GSC population.

Aberrant TET1 Methylation Closely Associated with CpG Island Methylator Phenotype in Colorectal Cancer.

Inactivation of methylcytosine dioxygenase, ten-eleven translocation (TET) is known to be associated with aberrant DNA methylation in cancers. Tumors with a CpG island methylator phenotype (CIMP), a distinct subgroup with extensive DNA methylation, show characteristic features in the case of colorectal cancer. The relationship between TET inactivation and CIMP in colorectal cancers is not well understood. The expression level of TET family genes was compared between CIMP-positive (CIMP-P) and CIMP-negative (CIMP-N) colorectal cancers. Furthermore, DNA methylation profiling, including assessment of the TET1 gene, was assessed in colorectal cancers, as well as colon polyps. The TET1 was silenced by DNA methylation in a subset of colorectal cancers as well as cell lines, expression of which was reactivated by demethylating agent. TET1 methylation was more frequent in CIMP-P (23/55, 42%) than CIMP-N (2/113, 2%, P < 0.0001) colorectal cancers. This trend was also observed in colon polyps (CIMP-P, 16/40, 40%; CIMP-N, 2/24, 8%; P = 0.002), suggesting that TET1 methylation is an early event in CIMP tumorigenesis. TET1 methylation was significantly associated with BRAF mutation but not with hMLH1 methylation in the CIMP-P colorectal cancers. Colorectal cancers with TET1 methylation have a significantly greater number of DNA methylated genes and less pathological metastasis compared to those without TET1 methylation (P = 0.007 and 0.045, respectively). Our data suggest that TET1 methylation may contribute to the establishment of a unique pathway in respect to CIMP-mediated tumorigenesis, which may be incidental to hMLH1 methylation. In addition, our findings provide evidence that TET1 methylation may be a good biomarker for the prediction of metastasis in colorectal cancer.

Development of new devices for translumenal endoscopic esophageal anastomosis.

AIM: This study aimed to develop new devices for translumenal endoscopic esophageal anastomosis-a stent and a ligating device-and to confirm the feasibility of our novel procedure using those devices. MATERIALS AND METHODS: We designed a ligating device as an overtube whose tip worked like the EVL device (Sumitomo Bakelite Co. Ltd., Tokyo, Japan). The newly developed procedure for anastomosis is as follows: a silicone elastic band, which was released from the device located at the upper esophagus, and a custom-made expandable stent, which was expanded by the balloon catheter in the lower esophagus, tightened the upper and lower esophageal walls. After producing the devices, we performed the anastomosis procedure in porcine models. RESULTS: A ligating device and an expandable stent were developed for this study. An ex vivo feasibility study was performed in three porcine models. Endoscopic visualization revealed that all steps in this procedure were technically successful. The median time needed to perform this procedure was 24 (range, 19-25) minutes. Patency of the anastomosis was confirmed in all specimens. CONCLUSIONS: Translumenal esophagoesophageal anastomosis using the new devices was feasible. The procedure time was sufficiently short for clinical use. An in vivo survival study is needed to confirm the safety and reliability of this procedure.

Chromatin regulator PRC2 is a key regulator of epigenetic plasticity in glioblastoma.

Tumor cell plasticity contributes to functional and morphologic heterogeneity. To uncover the underlying mechanisms of this plasticity, we examined glioma stem-like cells (GSC) where we found that the biologic interconversion between GSCs and differentiated non-GSCs is functionally plastic and accompanied by gain or loss of polycomb repressive complex 2 (PRC2), a complex that modifies chromatin structure. PRC2 mediates lysine 27 trimethylation on histone H3 and in GSC it affected pluripotency or development-associated genes (e.g., Nanog, Wnt1, and BMP5) together with alterations in the subcellular localization of EZH2, a catalytic component of PRC2. Intriguingly, exogenous expression of EZH2-dNLS, which lacks nuclear localization sequence, impaired the repression of Nanog expression under differentiation conditions. RNA interference (RNAi)-mediated attenuation or pharmacologic inhibition of EZH2 had little to no effect on apoptosis or bromodeoxyuridine incorporation in GSCs, but it disrupted morphologic interconversion and impaired GSC integration into the brain tissue, thereby improving survival of GSC-bearing mice. Pathologic analysis of human glioma specimens revealed that the number of tumor cells with nuclear EZH2 is larger around tumor vessels and the invasive front, suggesting that nuclear EZH2 may help reprogram tumor cells in close proximity to this microenvironment. Our results indicate that epigenetic regulation by PRC2 is a key mediator of tumor cell plasticity, which is required for the adaptation of glioblastoma cells to their microenvironment. Thus, PRC2-targeted therapy may reduce tumor cell plasticity and tumor heterogeneity, offering a new paradigm for glioma treatment.

Translumenal esophageal anastomosis for natural orifice translumenal endoscopic surgery: an ex vivo feasibility study.

AIM: This study aimed to develop a novel procedure for esophagoesophageal anastomosis for natural orifice translumenal endoscopic surgery (NOTES). MATERIALS AND METHODS: An ex vivo feasibility study was performed in eight porcine models. The procedure was as follows: (1) A BraceBar™ (Olympus Medical Systems Corp., Tokyo, Japan), a double T-bar suturing device, was placed endoscopically at the blind end of the upper esophagus (UE). (2) The blind end was incised, and the scope was advanced out of the esophagus. (3) A balloon catheter was inserted into the lower esophagus (LE). (4) The catheter and a thread on the BraceBar were withdrawn so that the end of the UE was inverted, and the LE was pulled into the UE. (5) After the catheter was removed, a short tube was placed inside the duplicated part of the esophagus via the transgastric route. (6) A double ligature was performed using a ligating device over the tube. A liquid leak test was performed after the procedure. RESULTS: All steps in this procedure were technically successful under the endoscopic visualization without any assistance from outside of the esophagus. The median time of this procedure was 31 (23-66) minutes. The median internal pressure of the UE was 122 (82-142) mm Hg when the anastomosed esophagus was separated into two specimens during the leak test. CONCLUSIONS: Translumenal esophagoesophageal anastomosis was feasible. The duration of the procedure was short, and the anastomoses appear to have sufficient strength for use in clinical practice. An in vivo survival study is needed to confirm the safety and reliability of this NOTES procedure.

Boundaries of transcriptionally silent chromatin in Saccharomyces cerevisiae.

In the budding yeast Saccharomyces cerevisiae, heterochromatic gene silencing has been found within HMR and HML silent mating type loci, the telomeres, and the rRNA-encoding DNA. There may be boundary elements that regulate the spread of silencing to protect genes adjacent to silenced domains from this epigenetic repressive effect. Many assays show that specific DNA regulatory elements separate a euchromatic locus from a neighboring heterochromatic domain and thereby function as a boundary. Alternatively, DNA-independent mechanisms such as competition between acetylated and deacetylated histones are also reported to contribute to gene insulation. However, the mechanism by which boundaries are formed is not clear. Here, the characteristics and functions of boundaries at silenced domains in S. cerevisiae are discussed.

Fub1p, a novel protein isolated by boundary screening, binds the proteasome complex.

Silenced chromatin domains are restricted to specific regions. Eukaryotic chromosomes are organized into discrete domains delimited by domain boundaries. From approximately 6,000 genes in Saccharomyces cerevisiae, we previously isolated 55 boundary genes. In this study, we focus on the molecular function of one of boundary genes, YCR076C/FUB1 (function of boundary), whose function has not been clearly defined in vivo. Biochemical analysis of Fub1p revealed that it interacted with multiple subunits of the 20S proteasome core particle (20S CP). To further clarify the functional link between Fub1p and proteasome, several proteasome mutants were analyzed. Although only 20S CP subunits were isolated as Fub1p interactors, a genetic interaction was also observed for component of 19S regulatory particle (19S RP) suggesting involvement of Fub1p with the whole proteasome. We also analyzed the mechanism of boundary establishment by using proteasome composition factor-deficient strains. Deletion of pre9 and ump1, whose products have effects on the 20S CP, resulted in a decrease in boundary function. Domain analyses of Fub1p identified a minimum functional domain in the C terminus that was essential for boundary establishment and showed a limited sequence homology to the human PSMF1, which is known to inhibit proteasome activity. Finally, boundary assay showed that human PSMF1 also exhibited boundary establishment activity in yeast. Our results defined the functional correlation between Fub1p and PSMF1.

Antenatally diagnosed giant multicystic dysplastic kidney resected during the neonatal period.

At 24 weeks of gestation, a fetus was suspected of having a huge intraabdominal cyst by fetal ultrasound. Multicystic dysplastic kidney (MCDK) was the most probable diagnosis; however, because a solid area was visualized in the large cystic lesion, a neoplasm of the kidney could not be ruled out. A 3529-g boy was born at 35 weeks of gestation by cesarean delivery. Eight days after birth, the tumor was resected. Histopathologic examination confirmed MCDK. The cause of MCDK in this patient was assumed to be ureteral obstruction in early fetal life. These findings suggested that the affected kidney had experienced mesenchyme-to-epithelium transition followed by interaction between the metanephric blastema and ureteral bud.

An animal model study for tissue-engineered trachea fabricated from a biodegradable scaffold using chondrocytes to augment repair of tracheal stenosis.

INTRODUCTION: We have designed an engineered graft fabricated from a biodegradable scaffold using chondrocytes and applied this construct to augment repair of tracheal stenosis. This study investigated the feasibility of using such tissue-engineered airways with autologous chondrocytes in a rabbit model. MATERIAL AND METHODS: Chondrocytes were isolated and expanded from the auricular cartilage of New Zealand white rabbits, then seeded onto composite 3-layer scaffolds consisting of a collagen sheet, a polyglycolic acid mesh, and a copolymer (l-lactide/epsilon-caprolactone) coarse mesh. The engineered grafts were implanted into a 0.5 x 0.8-cm defect created in the midventral portion of the cervical trachea. Gelatin sponges that slowly released basic fibroblast growth factor (b-FGF) were then placed on the constructs, which were retrieved 1 or 3 months after implantation. RESULTS: The biodegradable scaffold seeded with chondrocytes could maintain airway structure up to 3 months after implantation. Tracheal epithelial regeneration occurred in the internal lumen of this composite scaffold. Three months after implantation, staining of the sections showed cartilage accumulation in the engineered tracheal wall. CONCLUSION: This composite biodegradable scaffold may be useful for developing engineered trachea. A gelatin sponge slowly releasing b-FGF might enhance chondrogenesis.