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Background: Angiopoietin 1 and 2 regulate angiogenesis and vascular remodelling by interacting with the tyrosine kinase receptor Tie2, and inhibition of angiogenesis has shown promise in the treatment of ovarian cancer. We aimed to assess whether trebananib, a peptibody that inhibits binding of angiopoietin 1 and 2 to Tie2, improved progression-free survival when added to carboplatin and paclitaxel as first-line therapy in advanced epithelial ovarian, primary fallopian tube, or peritoneal cancer in a phase 3 clinical trial. Methods: TRINOVA-3, a multicentre, multinational, phase 3, double-blind study, was done at 206 investigational sites (hospitals and cancer centres)in 14 countries. Eligible patients were aged 18 years or older with biopsy-confirmed International Federation of Gynecology and Obstetrics (FIGO)stage III to IV epithelial ovarian, primary peritoneal, or fallopian tube cancers, and an ECOG performance status of 0 or 1. Eligible patients were randomly assigned (2:1)using a permuted block method (block size of six patients)to receive six cycles of paclitaxel (175 mg/m2)and carboplatin (area under the serum concentration-time curve 5 or 6)every 3 weeks, plus weekly intravenous trebananib 15 mg/kg or placebo. Maintenance therapy with trebananib or placebo continued for up to 18 additional months. The primary endpoint was progression-free survival, as assessed by the investigators, in the intention-to-treat population. Safety analyses included patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, number NCT01493505, and is complete. Findings: Between Jan 30, 2012, and Feb 25, 2014, 1164 patients were screened and 1015 eligible patients were randomly allocated to treatment (678 to trebananib and 337 to placebo). After a median follow-up of 27·4 months (IQR 17·7–34·2), 626 patients had progression-free survival events (405 [60%]of 678 in the trebananib group and 221 [66%]of 337 in the placebo group). Median progression-free survival did not differ between the trebananib group (15·9 months [15·0–17·6])and the placebo group (15·0 months [12·6–16·1])groups (hazard ratio 0·93 [95% CI 0·79–1·09]; p=0·36). 512 (76%)of 675 patients in the trebananib group and 237 (71%)of 336 in the placebo group had grade 3 or worse treatment-emergent adverse events; of which the most common events were neutropenia (trebananib 238 [35%]vs placebo 126 [38%])anaemia (76 [11%]vs 40 [12%]), and leucopenia (81 [12%]vs 35 [10%]). 269 (40%)patients in the trebananib group and 104 (31%)in the placebo group had serious adverse events. Two fatal adverse events in the trebananib group were considered related to trebananib, paclitaxel, and carboplatin (lung infection and neutropenic colitis); two were considered to be related to paclitaxel and carboplatin (general physical health deterioration and platelet count decreased). No treatment-related fatal adverse events occurred in the placebo group. Interpretation: Trebananib plus carboplatin and paclitaxel did not improve progression-free survival as first-line treatment for advanced ovarian cancer. The combination of trebananib plus carboplatin and paclitaxel did not produce new safety signals. These results show that trebananib in combination with carboplatin and paclitaxel is minimally effective in this patient population. Funding: Amgen. © 2019 Elsevier Ltd

Intermolecular enzyme complementation assay is a useful method for detecting protein-protein interactions. Specifically, bioluminescent signals produced from reconstructed split luciferase fragments are powerful tools for in vivo analysis because the bioluminescent signals have been visualized both in cultured cells and living animals. However, they are limited for detection and evaluation of biological events relevant to intermolecular protein-protein interactions. In this study, we constructed an intramolecular luciferase complementation probe for detecting target biomolecules other than protein-protein interactions. It consists of peptide-inserted firefly luciferase (PI-FLuc) containing a short peptide between internally divided firefly luciferase. The inserted short peptide triggers FLuc complementation or discomplementation and subsequent reactivation or inactivation of FLuc activity through its induced fit conformational changes. We chose RNA binding arginine rich motif (ARM) peptides, Rev and/or Tat, for model peptide insertion, and expressed constructed PI-FLuc probe variants using a wheat germ cell-free protein synthesis system. They showed FLuc activity changes, reactivation, or inactivation after binding to their specific RNA targets. Furthermore, to expand the versatility of the PI-FLuc RNA detection system, we designed split-RNA probes built to reform the ARM peptide binding site in the presence of arbitrarily selected target-RNA. As a result, the target RNA was homogeneously detected by FLuc luminescent signals mediated by a cooperative function of the PI-FLuc and split-RNA probe sets.

Neurodegeneration correlates with Alzheimer's disease (AD) symptoms, but the molecular identities of pathogenic amyloid β-protein (Aβ) oligomers and their targets, leading to neurodegeneration, remain unclear. Amylospheroids (ASPD) are AD patient-derived 10- to 15-nm spherical Aβ oligomers that cause selective degeneration of mature neurons. Here, we show that the ASPD target is neuronspecific Na+/K+-ATPase α3 subunit (NAKα3). ASPD-binding to NAKα3 impaired NAKα3-specific activity, activated N-type voltage-gated calcium channels, and caused mitochondrial calcium dyshomeostasis, tau abnormalities, and neurodegeneration. NMR and molecular modeling studies suggested that spherical ASPD contain N-terminal-Aβ- derived "thorns" responsible for target binding, which are distinct from low molecular-weight oligomers and dodecamers. The fourth extracellular loop (Ex4) region of NAKα3 encompassing Asn879 and Trp880 is essential for ASPD-NAKα3 interaction, because tetrapeptides mimicking this Ex4 region bound to the ASPD surface and blocked ASPD neurotoxicity. Our findings open up new possibilities for knowledge-based design of peptidomimetics that inhibit neurodegeneration in AD by blocking aberrant ASPD-NAKα3 interaction.

DNA-binding proteins with sequence specificities have a variety of applications. To create novel functional DNA-binding proteins, in vivo selection methods have been developed. There are, however, crucial problems with such methods, e.g., limitation of library size and difficulty of expression of toxic proteins for the host cells. In order to overcome these problems, we developed a novel way to select DNA-binding proteins using an in vitro ribosome display technique. The three zinc finger DNA-binding protein libraries, based on a Zif268 containing randomized sequence in each finger, were prepared and transcribed to mRNA in vitro. The ternary ribosomal complexes, formed by mRNA, ribosome, and translated DNA-binding protein during translation in a rabbit reticulocyte in vitro translation system, were selected with biotinylated target DNA fragments bound to streptavidin magnetic beads. The extracted mRNAs from the selected complexes were amplified using reverse transcription PCR and then sequenced. This is the first report of the selection of DNA-binding proteins involving an in vitro ribosome display technique.

Background: The multi-drug resistance 1 (MDR1) gene is reported to correlate with the function and the expression of P-glycoprotein (P-gp), and the carriers of MDR1 C3435T polymorphism are speculated to have an increased susceptibility to ulcerative colitis (UC) in western countries. The aim of this study is to investigate whether MDR1 C3435T polymorphism is a susceptible marker for the onset of UC in Japanese patients. Patients and Methods:We obtained blood samples from 38 patients with UC and that from 76 healthy controls, and genomic DNA from leucocytes was extracted. MDR1 C3435T polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism methods. The expression of P-gp was examined by immunohistochemistry in colonic tissues with UC. Results: Both the frequencies of TT genotype (p=0.023) and T allele (p=0.011) were significantly higher in the late onset UC groups than in the control group in Japanese UC patients. The protein of P-gp in colonic tissues showed lower expression in UC patients with TT genotype by immunohistological analysis. Conclusion: MDR1 C3435T polymorphisms are linked to the susceptibility of the late onset Japanese UC patients, probably via the lower exported activity of the related pathogenic environmental factors in colon.

Nonstructural protein 5A (NS5A) of hepatitis C virus (HCV) possesses multiple functions in the viral life cycle. NS5A is a phosphoprotein that exists in hyperphosphorylated and basally phosphorylated forms. Although the phosphorylation status of NS5A is considered to have a significant impact on its function, the mechanistic details regulating NS5A phosphorylation, as well as its exact roles in the HCV life cycle, are still poorly understood. In this study, we screened 404 human protein kinases via in vitro binding and phosphorylation assays, followed by RNA interference-mediated gene silencing in an HCV cell culture system. Casein kinase I-α (CKI-α) was identified as an NS5A-associated kinase involved in NS5A hyperphosphorylation and infectious virus production. Subcellular fractionation and immunofluorescence confocal microscopy analyses showed that CKI-α-mediated hyperphosphorylation of NS5A contributes to the recruitment of NS5A to low-density membrane structures around lipid droplets (LDs) and facilitates its interaction with core protein and the viral assembly. Phospho-proteomic analysis of NS5A with or without CKI-α depletion identified peptide fragments that corresponded to the region located within the low-complexity sequence I, which is important for CKI-α-mediated NS5A hyperphosphorylation. This region contains eight serine residues that are highly conserved among HCV isolates, and subsequent mutagenesis analysis demonstrated that serine residues at amino acids 225 and 232 in NS5A (genotype 2a) may be involved in NS5A hyperphosphorylation and hyperphosphorylation-dependent regulation of virion production. These findings provide insight concerning the functional role of NS5A phosphorylation as a regulatory switch that modulates its multiple functions in the HCV life cycle.

Antiemetic effect and safety of concurrent administration of ondansetron and other antiemetics (dexamethasone, domperidone and ethyl loflazepate), given for complete suppression of nausea/vomiting, were examined in 46 patients (109 courses) with gynecological cancer receiving single high-dose of cisplatin or carboplatin. As for the delayed emesis, antiemetic effect depending on the steroid treatment duration, given concurrently to ondansetron, was compared. The results were as follows; 1. In 78 courses, anticancer drugs were given concurrently to cisplatin or carboplatin only on Day 1. In the remaining 31 courses, those drugs were concurrently administered up to Day 6 at the longest. 2. Complete suppression (i.e., no onsets) rate of acute emesis was 64.2% (70/109 courses) for nausea, and 84.4% (92/109 courses) for vomiting. 3. When the complete suppression depending on duration of concomitant steroid was examined mainly in patients receiving CAP (cyclophosphamide, adriamycin and cisplatin), higher antiemetic effect, especially in nausea, was observed in those on concomitant steroids for 3 days compared to that for 1 day. 4. The food intake rate improved along with nausea symptoms. 5. No adverse event or laboratory abnormality due to the multi-antiemetic treatment was observed. Based on the above, the efficacy of the antiemetic treatment in this study was confirmed. In delayed emesis, concurrent steroids given for 3 days after chemotherapy were considered effective and were also regarded to improve food intake.