Correction: ESRP1 is overexpressed in ovarian cancer and promotes switching from mesenchymal to epithelial phenotype in ovarian cancer cells.

Since publication of the original article, the authors have noticed that there were errors in the labelling of Figures 6D and 6E. The correct figure and its legend are reproduced here. The authors wish to apologise for any inconvenience caused.

ESRP1 is overexpressed in ovarian cancer and promotes switching from mesenchymal to epithelial phenotype in ovarian cancer cells.

This corrects the article DOI: 10.1038/oncsis.2017.87.

ESRP1 is overexpressed in ovarian cancer and promotes switching from mesenchymal to epithelial phenotype in ovarian cancer cells.

Epithelial splicing regulatory protein 1 (ESRP1) and 2 (ESRP2), epithelial cell-specific regulators of alternative splicing, are downregulated during the epithelial-mesenchymal transition (EMT). These factors have roles in tumor progression and metastasis in some cancers; however, their expression and function in ovarian cancer (OC) remain unclear. We found that ESRP1 and ESRP2 mRNAs were expressed at higher levels in OC cells than in immortalized ovarian surface epithelial (IOSE) cells, and confirmed their overexpression in OC tissues at the protein level. The Cancer Genome Atlas (TCGA) data analysis revealed frequent gene amplification of ESRP1 in OC tissues; however, we detected no significant correlation between ESRP1 gene copy number and gene expression in OC cells. Importantly, expression of ESRP1 and ESRP2 was inversely correlated with DNA methylation in OC cells, and ESRP2 overexpression in OC tissues was significantly associated with DNA hypomethylation. Notably, survival analysis using TCGA data from 541 OC tissues revealed that high ESRP1 expression was significantly associated with shorter 5-year survival of patients. Ectopic ESRP1 expression in mesenchymal OC cells promoted cell proliferation but suppressed cell migration. Furthermore, we found that ESRP1 drives a switch from mesenchymal to epithelial phenotype characterized by reduced cell migration in association with induction of epithelial cell-specific variant of CD44 and ENAH. Taken together, our findings suggest that an epigenetic mechanism is involved in ESRP1 overexpression, and that ESRP1 has a role in OC progression.

Macelignan inhibits bee pathogenic fungi Ascophaera apis growth through HOG1 pathway.

Ascosphaera apis is a bee pathogen that causes bee larvae infection disease, to which treatment is not yet well investigated. The aim of this study was to investigate antifungal susceptibility in vitro against A. apis and to identify a new antifungal agent for this pathogen through minimal inhibitory concentration (MIC) assay and western blot analysis. Macelignan had 1.56 and 3.125 µg/mL MIC against A. apis after 24 and 48 h, respectively, exhibiting the strongest growth inhibition against A. apis among the tested compounds (corosolic acid, dehydrocostus lactone, loganic acid, tracheloside, fangchinoline and emodin-8-O-ß-D-glucopyranoside). Furthermore, macelignan showed a narrow-ranged spectrum against various fungal strains without any mammalian cell cytotoxicity. In spite of miconazole having powerful broad-ranged anti-fungal activity including A. apis, it demonstrated strong cytotoxicity. Therefore, even if macelignan alone was effective as an antifungal agent to treat A. apis, combined treatment with miconazole was more useful to overcome toxicity, drug resistance occurrence and cost effectiveness. Finally, HOG1 was revealed as a target molecule of macelignan in the anti-A. apis activity by inhibiting phosphorylation using S. cerevisiae as a model system. Based on our results, macelignan, a food-grade antimicrobial compound, would be an effective antifungal agent against A. apis infection in bees.

Macelignan inhibits bee pathogenic fungi Ascophaera apis growth through HOG1 pathway

Ascosphaera apis is a bee pathogen that causes bee larvae infection disease, to which treatment is not yet well investigated. The aim of this study was to investigate antifungal susceptibility in vitro against A. apis and to identify a new antifungal agent for this pathogen through minimal inhibitory concentration (MIC) assay and western blot analysis. Macelignan had 1.56 and 3.125 μg/mL MIC against A. apis after 24 and 48 h, respectively, exhibiting the strongest growth inhibition against A. apis among the tested compounds (corosolic acid, dehydrocostus lactone, loganic acid, tracheloside, fangchinoline and emodin-8-O-β-D-glucopyranoside). Furthermore, macelignan showed a narrow-ranged spectrum against various fungal strains without any mammalian cell cytotoxicity. In spite of miconazole having powerful broad-ranged anti-fungal activity including A. apis, it demonstrated strong cytotoxicity. Therefore, even if macelignan alone was effective as an antifungal agent to treat A. apis, combined treatment with miconazole was more useful to overcome toxicity, drug resistance occurrence and cost effectiveness. Finally, HOG1 was revealed as a target molecule of macelignan in the anti-A. apis activity by inhibiting phosphorylation using S. cerevisiae as a model system. Based on our results, macelignan, a food-grade antimicrobial compound, would be an effective antifungal agent against A. apis infection in bees.

Reactive molecular dynamics study of the pH-dependent dynamic structure of α-helix.

We have studied the α-helix to random coil transition using ReaxFF reactive molecular dynamics as a function of pH. Urea binding to peptides and associated interference with backbone H-bonds and charged side chains interactions, which can both denature the helices, have been studied previously using nonreactive force fields (Topol, I. A. J. Am. Chem. Soc. 2001, 123, 6054-6060). This study reveals new proton-transfer mechanisms related to the denaturation of α-helical structures, which cannot be captured by nonreactive molecular dynamics. In addition, we show that proton transfer between the solution and the peptide can break the α-helix hydrogen bonds, and consequently, at extreme pHs, a significant amount of helix will unravel. We also compare the effects of temperature in the denaturation mechanism. The ReaxFF findings are in significantly better agreement with ab initio calculations than previous nonreactive force field results, indicating the relevance of the reactive component on helical loss.

Preventive effect of fermented Maillard reaction products from milk proteins in cardiovascular health.

The aim of this study was to determine the dual effect of Maillard reaction and fermentation on the preventive cardiovascular effects of milk proteins. Maillard reaction products (MRP) were prepared from the reaction between milk proteins, such as whey protein concentrates (WPC) and sodium caseinate (SC), and lactose. The hydrolysates of MRP were obtained from fermentation by lactic acid bacteria (LAB; i.e., Lactobacillus gasseri H10, L. gasseri H11, Lactobacillus fermentum H4, and L. fermentum H9, where human-isolated strains were designated H1 to H15), which had excellent proteolytic and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities (>20%). The antioxidant activity of MRP was greater than that of intact proteins in assays of the reaction with 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and trivalent ferric ions; moreover, the effect of MRP was synergistically improved by fermentation. The Maillard reaction dramatically increased the level of antithrombotic activity and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) inhibitory effect of milk proteins, but did not change the level of activity for micellar cholesterol solubility. Furthermore, specific biological properties were enhanced by fermentation. Lactobacillus gasseri H11 demonstrated the greatest activity for thrombin and HMGR inhibition in Maillard-reacted WPC, by 42 and 33%, respectively, whereas hydrolysates of Maillard-reacted SC fermented by L. fermentum H9 demonstrated the highest reduction rate for micellar cholesterol solubility, at 52%. In addition, the small compounds that were likely released by fermentation of MRP were identified by size-exclusion chromatography. Therefore, MRP and hydrolysates of fermented MRP could be used to reduce cardiovascular risks.

In vitro and in vivo efficacy of drugs against the protozoan parasite Azumiobodo hoyamushi that causes soft tunic syndrome in the edible ascidian Halocynthia roretzi (Drasche).

It was discovered recently that infection by a protozoan parasite, Azumiobodo hoyamushi, is the most probable cause for soft tunic syndrome in an edible ascidian, Halocynthia roretzi (Drasche). In an attempt to develop measures to eradicate the causative parasite, various drugs were tested for efficacy in vitro and in vivo. Of the 20 antiprotozoal drugs having different action mechanisms, five were found potent (24-h EC50  < 10 mg L(-1) ) in their parasite-killing effects: formalin, H2 O2 , bithionol, ClO2 and bronopol. Moderately potent drugs (10 < 24-h EC50  < 100 mg L(-1) ) were quinine, fumagillin, amphotericin B, ketoconazole, povidone-iodine, chloramine-T and benzalkonium chloride. Seven compounds, metronidazole, albendazole, paromomycin, nalidixic acid, sulfamonomethoxine, KMnO4 , potassium monopersulphate and citric acid, exhibited EC50  > 100 mg L(-1) . When ascidians were artificially infected with A. hoyamushi, treated using 40 mg L(-1) formalin, bronopol, ClO2 , or H2 O2 for 1 h and then monitored for 24 h, very low mortality was observed. However, the number of surviving parasite cells in the ascidian tunic tissues was significantly reduced by treating with 40 mg L(-1) formalin or ClO2 for 1 h. The data suggest that we might be able to develop a disinfection measure using a treatment regimen involving commonly available drugs.

Mitochondrial swelling and microtubule depolymerization are associated with energy depletion in axon degeneration.

Although mitochondrial dysfunction is intimately related to axonal degeneration following nerve injury, the molecular mechanisms of mitochondrial swelling and its mechanistic relation to axonal degeneration are largely unknown. Previous studies have demonstrated that axonal degeneration in the injured peripheral nerves shows two morphologically distinct phases: (1) A latency period (∼24h), in which the morphology of axonal cytoskeletons seems unchanged, followed by (2) an execution period (36-48h), which shows a catastrophic granular degeneration of most axonal structures in rodent axons. In the present study, we found that, in the sciatic nerve axotomy model, energy failure and microtubule depolymerization occurred during the latency period whereas mitochondrial swelling and neurofilament degradation started in the execution period. The energy repletion with NAD or an NAD/pyruvate mixture inhibited microtubule depolymerization, mitochondrial swelling and axonal degeneration in transected sciatic nerve axons. In addition, microtubule perturbing agents enhanced axonal degeneration and mitochondrial swelling. Extracellular calcium chelation did not affect energy failure, microtubule depolymerization or mitochondrial swelling, but it did prevent neurofilament degradation. These findings suggest that an early disturbance in energy dynamics regardless of mitochondrial swelling might be a key trigger for the initiation of axonal degeneration and that extracellular calcium influx is a late effector for neurofilament degradation.

Effects of dietary persimmon peel and its ethanol extract on the production performance and liver lipids in the late stage of egg production in laying hens.

The purpose of this study was to investigate the dietary effects of persimmon peel (PP) and PP ethanol extract (PPE) on egg production, egg quality, and liver lipids in the late stage of egg production in laying hens. One hundred and twenty 50-wk-old Hy-Line Brown layers (n = 120) were fed different diets. Four replicate groups of 6 hens each were randomly assigned to 5 dietary treatments. The 5 dietary treatments were as follows: i) CON, basal diet; ii) PP 0.15, CON+0.15% PP (0.035% tannin); iii) PP 0.5, CON +0.5% PP (0.117% tannin); iv) PPE 0.075, CON+0.075% PPE (0.03% tannin); and v) PPE 0.25, CON+0.25% PPE (0.11% tannin). The total tannin concentration of PPE was higher (p<0.05) than that of PP. Egg production in the PP 0.5 group was higher than in the other groups. Egg production and mass of hens in the PPE 0.25 group showed a greater decrease than that in the other groups (p<0.05). Eggshell color in the PP 0.15, PP 0.5, and PPE 0.075 groups was lighter than that of the control group (p<0.05). The Haugh unit for the groups that were fed PP and PPE were significantly higher than that in the other groups after 7 d of storage (p<0.05). Therefore, PP seems an effective feed additive for improving the production performance and egg quality in late stage laying hens.

Prevalence of classical swine fever virus in domestic pigs in South Korea: 1999-2011.

The major policy for eradication of classical swine fever (CSF) in South Korea has focused on the implementation of compulsory vaccination of the susceptible pig population. A vaccine strain of CSF virus, the LOM strain, is used to maintain high herd seroconversion, a practice complementary to the 'stamping-out policy' and restriction of animal movement during disease outbreaks. To survey for the prevalence of CSF in domestic pigs in South Korea over the past 13 years (1999-2011), we tested 4 193 782 and 1 162 645 samples for antibodies and antigens, respectively. Whereas seropositivity for CSF antibodies has been maintained at over 95% in the mainland, in Jeju Island, where no-vaccination has been administered since 1999, seroprevalence has been below 1% during the last 3 years of study (2009-2011). The highest number of outbreaks in South Korea occurred in 2002 and 2003; since then, outbreaks have decreased each year, with the last CSF outbreak recorded in 2009. No outbreaks have occurred during the past 3 years, and a high level of herd immunity has been maintained in the mainland pig population for 8 years; therefore, South Korea could now switch to a no-vaccination policy throughout the country. However, the constant threat of the re-emergence of the disease in the susceptible pig population should be the main consideration in planning and carrying out the last phase of the CSF eradication process.

Clinical significance of CD151 overexpression in subtypes of invasive breast cancer.

BACKGROUND: CD151 is a member of the tetraspanin family, which interacts with laminin-binding integrins and other tetraspanins. This protein is implicated in motility, invasion, and metastasis of cancer cells, but the prevalence of CD151 expression in subtypes of breast cancers and its influence on clinical outcome remains to be evaluated. METHODS AND RESULTS: The immunohistochemistry-based tissue microarray analysis showed that 127 (14.3%) cases overexpressed CD151 among 886 breast cancer patients. CD151 overexpression was found to be significantly associated with larger tumour size, higher nodal stage, advanced stage, absence of oestrogen receptor and progesterone receptor, and human epidermal growth factor receptor 2 overexpression. CD151 overexpression resulted in poorer overall survival (OS) (P<0.001) and disease-free survival (P=0.02), and stage II and III patients with CD151 overexpression demonstrated substantially poorer OS (P=0.0474 and 0.0169). In the five subtypes analyses, CD151 overexpression retained its adverse impact on OS in the Luminal A (P=0.0105) and quintuple-negative breast cancer (QNBC) subtypes, one subgroup of triple-negative breast cancer (P=0.0170). Multivariate analysis that included stage, subtype, and adjuvant chemotherapy showed that CD151 overexpression was independently associated with poor OS in invasive breast cancer. CONCLUSION: CD151 overexpression may be a potential molecular therapeutic target for breast cancer, especially in QNBC subtype and more advanced stages of breast cancer.

Epigenetic control of metastasis-associated protein 1 gene expression by hepatitis B virus X protein during hepatocarcinogenesis.

Expression of metastasis-associated protein 1 (MTA1) gene correlates with the degree of invasion and metastasis in hepatocellular carcinoma (HCC). Expression of MTA1 is induced by hepatitis B virus X protein (HBx); however, little is known about the transcriptional regulation of MTA1 gene expression. Here, we report that the 5'-flanking region of the human MTA1 promoter contains two CpG islands. Transient expression of HBx in Chang liver cells increased the methylation of the CpG island1 from 18 to 49% when measured by bisulfite-modified direct sequencing. Chromatin immunoprecipitation showed that HBx recruited DNA methyltransferase 3a (DNMT3a) and DNMT3b to the CpG island1. In silico analysis of CpG island1 predicted the existence of putative p53-binding sequences. p53 was pulled down by a DNA probe encoding the p53-binding sequences but not by the methylated DNA probe. The mouse MTA1 promoter also contains a CpG island encoding a p53-binding sequence of which p53 binding was decreased in the presence of HBx, and the expression of MTA1 and DNMT3 was increased in the liver of HBx-transgenic mice. Comparison of MTA1 and DNMT3a expression in the human normal liver and HCC specimens produced a significant correlation coefficient >0.5 (r=0.5686, P=0.0001) for DNMT3a, and a marginally significant coefficient (r=0.3162, P=0.0103) for DNMT3b. These data show that HBx induces methylation of CpG island in the MTA1 promoter, which interferes with DNA binding of p53 in the specific DNA region. This result may explain the molecular mechanism responsible for the induction of MTA1 gene expression by HBx.

Detection of Merkel cell polyomavirus in Merkel cell carcinomas and small cell carcinomas by PCR and immunohistochemistry.

Recently, the clonal integration of a new human polyomavirus (Merkel cell polyomavirus or MCPyV) has been reported in Merkel cell carcinoma (MCC). In order to investigate the presence of MCPyV in small cell carcinomas (SCCs) and small round cell tumors (SRCTs), we collected formalin-fixed paraffin-embedded tissue specimens including 14 MCCs, 24 SCCs, 7 Ewing sarcoma/primitive neuroectodermal tumors (ES/PNETs) and 5 neuroblastomas. We also collected specimens of other cancers including 12 malignant melanomas, 10 breast, 10 ovarian and 20 gastric cancers. We used 3 primer sets for which the sequences were previously published (LT1, LT3, and VP1) and 3 newly designed primer sets (LT1-1, LT1-1a, and LT3a). Quantitative real-time PCR was also performed with the LTq primer set. Nested PCR using the LT3a primer set detected more cases of MCPyV infection in MCC. In total, 12 of 14 (85.7%) MCC cases were positive for MCPyV by PCR, which was consistent with published data. Some SCC specimens were also positive for MCPyV (37.5%) by PCR. PCR products from MCC and SCC cases showed premature truncation and frameshift mutation. Furthermore, one case of ES/PNET and one gastric carcinoma showed MCPyV DNA. However, MCPyV DNA and transcript were only detected in MCCs with quantitative real-time PCR analysis. In addition, 11 of 13 (84.6%) MCC cases and 6 of 23 (26.1%) SCC cases showed immunoreactivity with monoclonal antibodies against MCPyV large T-antigen. Considering both PCR and IHC results, MCPyV was detected in all MCCs tested. The presence of MCPyV in all MCC cases tested and in some SCC cases suggests that MCPyV may be involved in the malignant transformation.

The implication of nigrostriatal dopaminergic degeneration in the pathogenesis of REM sleep behavior disorder.

BACKGROUND AND PURPOSE: The pathogenesis of rapid eye movement (REM) sleep behavior disorder (RBD) is not clear despite its frequent association with Parkinson's disease (PD). We investigated whether the nigrostriatal dopaminergic system is involved in the development of idiopathic RBD. METHODS: Fourteen patients with RBD, 14 patients with PD and 12 normal controls were included in the study. The diagnosis of RBD was confirmed on polysomnography. All the participants performed single-photon emission computed tomography imaging 3 h after injection of [(123)I]FP-CIT. During REM sleep of the RBD patients, each 30-s epoch was rated as 'tonic' when there was at least 50% of tonically maintained chin electromyography (EMG) activity in the epoch. Phasic EMG activities were calculated as the percentage of 3-s mini-epoch containing phasic EMG events (leg and chin, separately). RESULTS: The RBD patients showed a trend of lower binding in the striatum than the normal controls (P = 0.07), and the significance was revealed in the putamen (P = 0.02). However, in 11 individual cases of the 14 RBD patients, the dopamine transporter (DAT) densities in the putamen still remained within the normal range. In the RBD patients, there was no correlation between EMG activities and DAT densities. CONCLUSIONS: Nigrostriatal dopaminergic degeneration could be a part of the pathogenesis of RBD, but not essential for the development of RBD. The lack of correlation between RBD severity and DAT densities suggests that another pathogenic process not related to nigrostriatal dopaminergic transmission may be implicated in RBD.

Apicidin, the histone deacetylase inhibitor, suppresses Th1 polarization of murine bone marrow-derived dendritic cells.

Apicidin is a fungal metabolite shown to exhibit anti-proliferative, anti-invasive, and anti-inflammatory properties by the inhibition of histone deacetylase (HDAC). However, the effects of apicidin on the maturation and immunostimulatory function of dendritic cells (DCs) remain unknown. In this study, we investigated whether apicidin modulates surface molecule expression, cytokine production, endocytosis capacity, and underlying signaling pathways in murine bone marrow-derived DCs. We observed that apicidin significantly attenuated surface molecule expression in LPS-stimulated DCs, suppressed production of interleukin (IL)-12 and proinflammatory cytokines (IL-6 and TNF-alpha) by DCs, and reduced IFN-gama production by T cells. The apicidin-treated DCs were found to be highly efficient in antigen capture via mannose receptor-mediated endocytosis. Apicidin also inhibited LPS-induced MAPK activation and NF-kB nuclear translocation in DCs. Moreover, the apicidin-treated DCs were incapable of inducing Th1 responses and normal cell-mediated immune responses. These novel findings not only provide new insights into the immunopharmacological role of apicidin in terms of its effects on DCs, but also broaden current perspectives of the immunopharmacological functions of apicidin, and have implications for the development of therapeutic adjuvants for the treatment of DC-related acute and chronic diseases.

Galectin-3 stabilizes heterogeneous nuclear ribonucleoprotein Q to maintain proliferation of human colon cancer cells.

Comparative analysis of proteomes using 5-fluorouracil (5-FU)-resistant human colon cancer cell line revealed that decreased galectin-3 expression was significantly associated with retarded proliferation. However, in the presence of 5-FU proliferation rate of cells with suppressed galectin-3 expression did not differ from that of cells with normal galectin-3 expression, even galectin-3 suppression augmented apoptosis. Mechanism by which galectin-3 regulates cancer cell proliferation has been identified in immunoprecipitates of the anti-galectin-3 antibody. Heterogeneous nuclear ribonucleoprotein Q (hnRNP Q) was identified as a protein interacting with galectin-3. Interestingly, while galectin-3 protein was not affected by the hnRNP Q level, its suppression was accompanied by a decrease in hnRNP Q expression. The present study demonstrates that galectin-3 stabilizes hnRNP Q via complex formation, and reduction in the hnRNP Q level leads to slow proliferation and less susceptibility to 5-FU.

Progress in understanding the neuronal SNARE function and its regulation.

Vesicle budding and fusion underlies many essential biochemical deliveries in eukaryotic cells, and its core fusion machinery is thought to be built on one protein family named soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE). Recent technical advances based on site-directed fluorescence labelling and nano-scale detection down to the single-molecule level rapidly unveiled the protein and the lipid intermediates along the fusion pathway as well as the molecular actions of fusion effectors. Here we summarize these new exciting findings in context with a new mechanistic model that reconciles two existing fusion models: the proteinaceous pore model and the hemifusion model. Further, we attempt to locate the points of action for the fusion effectors along the fusion pathway and to delineate the energetic interplay between the SNARE complexes and the fusion effectors.

Hepatitis B virus X protein induces the expression of MTA1 and HDAC1, which enhances hypoxia signaling in hepatocellular carcinoma cells.

Expression level of metastasis-associated protein 1 (MTA1) is closely related to tumor growth and metastasis in various cancers. Although increased expression level of MTA1 was observed in hepatocellular carcinoma (HCC), role of MTA1 complex containing histone deacetylase (HDAC) in hepatitis B virus (HBV)-associated hepatocarcinogenesis has not been studied. Here, we demonstrated that HBx strongly induced the expression of MTA1 and HDAC1 genes at transcription level. MTA1 and HDAC1/2 physically associated with hypoxia-inducible factor-1 alpha (HIF-1 alpha) in vivo in the presence of HBx, which was abolished by knockdown of MTA1 by short interfering RNA (siRNA). HBx induced deacetylation of the oxygen-dependent degradation domain of HIF-1 alpha, which was accompanied with dissociation of prolyl hydroxylases and von Hippel-Lindau tumor suppressor from HIF-1 alpha. These results indicate that HBx-induced deacetylation is important for proteasomal degradation of HIF-1 alpha. Further, we observed that protein levels of MTA1 and HDAC1 were increased in the liver of HBx-transgenic mice. Also, there was a higher expression of HDAC1 in HCC than in the adjacent non-tumorous cirrhotic nodules in 10 out of 12 human HBV-associated HCC specimens. Together, our data indicate a positive cross talk between HBx and the MTA1/HDAC complex in stabilizing HIF-1 alpha, which may play a critical role in angiogenesis and metastasis of HBV-associated HCC.