Increased amyloidogenic processing of transgenic human APP in X11-like deficient mouse brain

<p>Abstract</p> <p>Background</p> <p>X11-family proteins, including X11, X11-like (X11L) and X11-like 2 (X11L2), bind to the cytoplasmic domain of amyloid β-protein precursor (APP) and regulate APP metabolism. Both X11 and X11L are expressed specifically in brain, while X11L2 is expressed ubiquitously. X11L is predominantly expressed in excitatory neurons, in contrast to X11, which is strongly expressed in inhibitory neurons. <it>In vivo </it>gene-knockout studies targeting X11, X11L, or both, and studies of X11 or X11L transgenic mice have reported that X11-family proteins suppress the amyloidogenic processing of endogenous mouse APP and ectopic human APP with one exception: knockout of X11, X11L or X11L2 has been found to suppress amyloidogenic metabolism in transgenic mice overexpressing the human Swedish mutant APP (APPswe) and the mutant human PS1, which lacks exon 9 (PS1dE9). Therefore, the data on X11-family protein function in transgenic human APP metabolism <it>in vivo </it>are inconsistent.</p> <p>Results</p> <p>To confirm the interaction of X11L with human APP ectopically expressed in mouse brain, we examined the amyloidogenic metabolism of human APP in two lines of human APP transgenic mice generated to also lack X11L. In agreement with previous reports from our lab and others, we found that the amyloidogenic metabolism of human APP increased in the absence of X11L.</p> <p>Conclusion</p> <p>X11L appears to aid in the suppression of amyloidogenic processing of human APP in brain <it>in vivo</it>, as has been demonstrated by previous studies using several human APP transgenic lines with various genetic backgrounds. X11L appears to regulate human APP in a manner similar to that seen in endogenous mouse APP metabolism.</p

NOVA regulates Dcc alternative splicing during neuronal migration and axon guidance in the spinal cord.

RNA-binding proteins (RBPs) control multiple aspects of post-transcriptional gene regulation and function during various biological processes in the nervous system. To further reveal the functional significance of RBPs during neural development, we carried out an in vivo RNAi screen in the dorsal spinal cord interneurons, including the commissural neurons. We found that the NOVA family of RBPs play a key role in neuronal migration, axon outgrowth, and axon guidance. Interestingly, Nova mutants display similar defects as the knockout of the Dcc transmembrane receptor. We show here that Nova deficiency disrupts the alternative splicing of Dcc, and that restoring Dcc splicing in Nova knockouts is able to rescue the defects. Together, our results demonstrate that the production of DCC splice variants controlled by NOVA has a crucial function during many stages of commissural neuron development

A Phase I/II Study of Crizotinib for Recurrent or Refractory Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma and a Phase I Study of Crizotinib for Recurrent or Refractory Neuroblastoma : Study Protocol for a Multicenter Single-arm Open-label Trial

Crizotinib is an inhibitor of multiple tyrosine kinases, including the anaplastic lymphoma kinase (ALK). Responses to crizotinib have also been reported in patients with ALK-positive anaplastic large-cell lymphoma (ALCL) and solid tumors with ALK-mutation, including neuroblastoma. Optimal treatment for patients with recurrent or refractory ALK-positive ALCL and neuroblastoma has not been established. There is a need to develop new drugs for these patients. The objectives of this trial are to evaluate the tolerability and safety of crizotinib in Japanese patients with recurrent/refractory ALK-positive ALCL or neuroblastoma (phase I) and its efficacy in recurrent/refractory ALK-positive ALCL (phase II)

A Multicenter, Open-label, Clinical Trial to Assess the Effectiveness and Safety of Allogeneic Hematopoietic Stem Cell Transplantation Using Reduced-intensity Conditioning in Relapsed/refractory Anaplastic Large-cell Lymphoma in Children

No standard treatment for relapsed or refractory anaplastic large-cell lymphoma (ALCL) has been established. This study is a multicenter, open-label trial to examine the effectiveness and safety of transplantation with reduced-intensity conditioning (RIC) for patients under 20 years old with relapsed or refractory ALCL. We defined RIC as the administration of fludarabine (30 mg/m2/day) for five days plus melphalan (70 mg/m2/day) for two days and total body irradiation at 4 Gy, followed by allogeneic hematopoietic stem cell transplantation

Oncostatin M suppresses IL31RA expression in dorsal root ganglia and interleukin-31-induced itching

BackgroundAtopic dermatitis (AD) is a chronic inflammatory skin disease characterized by intermittent itchy rash. Type 2 inflammatory cytokines such as interleukin (IL)-4, IL-13, and IL-31 are strongly implicated in AD pathogenesis. Stimulation of IL-31 cognate receptors on C-fiber nerve endings is believed to activate neurons in the dorsal root ganglion (DRG), causing itch. The IL-31 receptor is a heterodimer of OSMRβ and IL31RA subunits, and OSMRβ can also bind oncostatin M (OSM), a pro-inflammatory cytokine released by monocytes/macrophages, dendritic cells, and T lymphocytes. Further, OSM expression is enhanced in the skin lesions of AD and psoriasis vulgaris patients.ObjectiveThe current study aimed to examine the contributions of OSM to AD pathogenesis and symptom expression.MethodsThe expression levels of the OSM gene (OSM) and various cytokine receptor genes were measured in human patient skin samples, isolated human monocytes, mouse skin samples, and mouse DRG by RT-qPCR. Itching responses to various pruritogens were measured in mice by counting scratching episodes.ResultsWe confirmed overexpression of OSM in skin lesions of patients with AD and psoriasis vulgaris. Monocytes isolated from the blood of healthy subjects overexpressed OSM upon stimulation with IL-4 or GM-CSF. Systemic administration of OSM suppressed IL31RA expression in the mouse DRG and IL-31-stimulated scratching behavior. In contrast, systemic administration of OSM increased the expression of IL-4- and IL-13-related receptors in the DRG.ConclusionThese results suggest that OSM is an important cytokine in the regulation of skin monocytes, promoting the actions of IL-4 and IL-13 in the DRG and suppressing the action of IL-31. It is speculated that OSM released from monocytes in skin modulates the sensitivity of DRG neurons to type 2 inflammatory cytokines and thereby the severity of AD-associated skin itch

NOVA2-mediated RNA regulation is required for axonal pathfinding during development.

The neuron specific RNA-binding proteins NOVA1 and NOVA2 are highly homologous alternative splicing regulators. NOVA proteins regulate at least 700 alternative splicing events in vivo, yet relatively little is known about the biologic consequences of NOVA action and in particular about functional differences between NOVA1 and NOVA2. Transcriptome-wide searches for isoform-specific functions, using NOVA1 and NOVA2 specific HITS-CLIP and RNA-seq data from mouse cortex lacking either NOVA isoform, reveals that NOVA2 uniquely regulates alternative splicing events of a series of axon guidance related genes during cortical development. Corresponding axonal pathfinding defects were specific to NOVA2 deficiency: Nova2-/- but not Nova1-/- mice had agenesis of the corpus callosum, and axonal outgrowth defects specific to ventral motoneuron axons and efferent innervation of the cochlea. Thus we have discovered that NOVA2 uniquely regulates alternative splicing of a coordinate set of transcripts encoding key components in cortical, brainstem and spinal axon guidance/outgrowth pathways during neural differentiation, with severe functional consequences in vivo

The Effect of Interim FDG-PET-guided Response-Adapted Therapy in Pediatric Patients with Hodgkin’s Lymphoma (HL-14) : Protocol for a Phase II Study

This trial enrolls patients with untreated Hodgkin’s lymphoma aged<20 years at diagnosis and examines the effects of omitting radiation therapy if the FDG-positron emission tomography (PET) findings after two completed cycles of combination chemotherapy are negative. It thereby aims to determine whether patients who truly require radiation therapy can be identified by FDG-PET. If so, this modality could be used to omit radiation therapy for all other patients, decreasing the risk of serious long-term complications without affecting survival rates. The outcomes of patients for whom FDG-PET is used to assess early treatment response will also be determined

Intracellular Trafficking of the Amyloid β-Protein Precursor (APP) Regulated by Novel Function of X11-Like

Background: Amyloid beta (A beta), a causative peptide of Alzheimer's disease, is generated by intracellular metabolism of amyloid beta-protein precursor (APP). In general, mature APP (mAPP, N- and O-glycosylated form) is subject to successive cleavages by alpha- or beta-, and gamma-secretases in the late protein secretory pathway and/or at plasma membrane, while immature APP (imAPP, N-glycosylated form) locates in the early secretory pathway such as endoplasmic reticulum or cis-Golgi, in which imAPP is not subject to metabolic cleavages. X11-like (X11L) is a neural adaptor protein composed of a phosphotyrosine-binding (PTB) and two C-terminal PDZ domains. X11L suppresses amyloidogenic cleavage of mAPP by direct binding of X11L through its PTB domain, thereby generation of A beta lowers. X11L expresses another function in the regulation of intracellular APP trafficking. Methodology: In order to analyze novel function of X11L in intracellular trafficking of APP, we performed a functional dissection of X11L. Using cells expressing various domain-deleted X11L mutants, intracellular APP trafficking was examined along with analysis of APP metabolism including maturation (O-glycosylation), processing and localization of APP. Conclusions: X11L accumulates imAPP into the early secretory pathway by mediation of its C-terminal PDZ domains, without being bound to imAPP directly. With this novel function, X11L suppresses overall APP metabolism and results in further suppression of Ab generation. Interestingly some of the accumulated imAPP in the early secretory pathway are likely to appear on plasma membrane by unidentified mechanism. Trafficking of imAPP to plasma membrane is observed in other X11 family proteins, X11 and X11L2, but not in other APP-binding partners such as FE65 and JIP1. It is herein clear that respective functional domains of X11L regulate APP metabolism at multiple steps in intracellular protein secretory pathways

Retrotrigonal Layer Dissection from a Posterior Approach Enables Bladder Neck Preservation in Robot-Assisted Radical Prostatectomy

Background: We developed a novel surgical technique: dissection of the retrotrigonal layer from a posterior approach in robot-assisted radical prostatectomy (RARP). This approach enables earlier access to the posterior space during bladder neck dissection and helps preserve the bladder neck. We evaluated the safety and efficacy of this technique in terms of bladder neck preservation Methods: We retrospectively reviewed 238 consecutive patients who underwent RARP using this technique from August 2021 to September 2023. Key metrics included the success rate of accessing the posterior space prior to bladder neck opening during the dissection and the rate of bladder neck preservation. In addition, oncological and surgical safety, as well as continence recovery, were assessed. Results: The median age and prostate-specific antigen level were 72 (65–75) years and 7.35 (5.40–11.5) ng/mL, respectively. In 153 (64%) patients, the posterior space was successfully accessed before bladder neck opening, with the success rate increasing from 56% in the series’ first half to 72% in the second half (p = 0.015). The bladder neck was preserved in 120 (53%) patients, and this rate increased from 39% in the first half to 63% in the second half (p = 0.0004). Positive surgical margins at the junction between the prostate and bladder were observed in 10 cases (4%). Bladder neck preservation correlated with early continence recovery (hazard ratio 1.37 [95% confidence interval 1.03–1.83], p = 0.030). The grade 3 complication associated with this technique occurred in one case (0.5%). Conclusion: Retrotrigonal layer dissection from a posterior approach in RARP enhances the safety and ease of bladder neck dissection and aids in its preservation, potentially leading to improved continence recovery