Abstract 1996: Regulation of RNA splicing of the ErbB family receptors by the splicing cofactor SON

For women, breast cancer has the highest number of annual diagnoses and causes the second highest number of cancer related deaths per year. Receptor tyrosine kinases like those in the ErbB family play a crucial role in breast cancer progression by providing cancer cells proliferative and anti-apoptotic advantages. By targeting the ErbB family with monoclonal antibodies and kinase inhibitors, the prognosis of patients has improved dramatically, but resistance to these therapies does occur which requires novel therapies to be developed. One promising approach to circumvent drug resistance and inhibit tumor growth is to interrupt the elements that regulate the ErbB family protein expression such as RNA processing. The RNA transcripts of the ErbB family members must be spliced to be functional due to their immense size and the number of introns in these genes. Therefore, any alteration to this process could adversely affect tumor cells. SON, a splicing cofactor, has emerged as a protein of interest in cancer research because of its ability to impact the cell cycle and apoptosis by aiding in pre-mRNA maturation. Based on our preliminary data, we hypothesize that SON is required for ErbB family receptor-driven breast cancer by promoting the expression of not only the ErbB family proteins but also certain ErbB downstream effectors through enhanced RNA splicing. Our studies show that knocking down SON with two independent siRNAs significantly lowers the protein expression of ErbB family proteins ErbB1, ErbB2, and ErbB3 in cancer cells. At the mRNA level, the functional ErbB2 and ErbB3 transcripts decrease because introns are inappropriately retained which causes RNA degradation. These changes lead to a decrease in proliferation and increased apoptosis in breast cancer cells. After examining multiple major signaling pathways with a phospho-kinase array, we found that the activation of several critical ErbB family receptor downstream cascades that respond to stress (p38/JNK) and ensure survival (Akt) are suppressed especially in cells that have high levels of ErbB2. Patient samples were also analyzed which showed that breast tumors tend to have higher levels of SON, and the five year survival for these patients is decreased. Taken together, these data indicate that we have discovered SON as a novel ErbB family receptor splicing factor that may play an important role in breast cancer progression. Our future studies will focus on investigating more in-depth mechanisms by which SON regulates the RNA splicing of the ErbB family and evaluating whether SON can serve as a therapeutic target for breast cancer treatment by using drug and in vivo studies.

Citation Format: Joshua Phillips, Jung-Hyun Kim, Sangbin Lim, Erin Ahn, Ming Tan. Regulation of RNA splicing of the ErbB family receptors by the splicing cofactor SON. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1996.

OC-11 - Anticoagulation therapy in selected cancer patients at risk of recurrence of venous thromboembolism

INTRODUCTION

Venous thromboembolism (VTE) in cancer patients is an increasingly frequent clinical problem. The overall impact of VTE on cancer patients can be considerable. Targeted patient selection by identifying patients with clinically significant recurrent VTE may have wider health economic benefits whilst reducing patient risk through over-treatment. In the UK, dalteparin is one licensed anticoagulant for the extended treatment and prevention of recurrence of VTE in cancer patients. Rivaroxaban is a highly selective direct Factor Xa inhibitor with oral bioavailability.

AIM

To assess VTE recurrence in selected cancer patients at risk of recurrence of VTE treated with rivaroxaban or dalteparin. The secondary objectives include safety, acceptability, biomarker identification and health economics.

MATERIALS AND METHODS

Select-d is a prospective, randomised, open label, multicentre pilot trial comparing dalteparin (200 IU/kg daily subcutaneously for 1 month and 150 IU/kg months 2-6); and rivaroxaban (15mg orally twice daily for 3 weeks and 20mg once daily for 6 months in total) for cancer patients with VTE - symptomatic and incidental pulmonary embolism (P)E or symptomatic lower limb proximal deep vein thrombosis (DVT) - with a second placebo-controlled randomisation (rivaroxaban vs placebo) comparing the duration of therapy (6 vs 12 months) in all patients with PE and those with a DVT who are residual vein thrombosis (RVT) positive. 70% of DVT patients are estimated to be RVT positive after initial treatment. 530 patients are being recruited toprovide reliable estimates of the primary outcome (VTE recurrence rates) to within the 95% confidence interval of 8% assuming VTE rates are 10% at six months.

RESULTS

As of 1st December 2015, 264 patients have been recruited from 61 open sites across the UK. Preliminary data indicate that the majority of patients presented with solid tumours (98%), ranging from early or locally advanced (41%) to metastatic disease (57%), and primarily comprising colorectal, lung, and breast malignancies. Only a small number of select-d patients presented with haematological malignancies (2%), which included; leukaemia, myeloma and lymphoma. Over half of the select-d patients had an incidental PE (54%); the remainder had symptomatic PE or DVT (46%). The median number of hours on anticoagulation prior to starting select-d randomised treatment was 48 hours.

CONCLUSIONS

select-d is the first randomised trial for treatment of VTE, investigating the direct oral anticoagulants vs a low molecular weight heparin in patients with cancer. The results will support optimal treatment for this key patient group and are eagerly awaited.

Cognitive Control of Episodic Memory in Schizophrenia: Differential Role of Dorsolateral and Ventrolateral Prefrontal Cortex

Background: Dorsal (DLPFC) and ventral (VLPFC) subregions in lateral prefrontal cortex play distinct roles in episodic memory, and both are implicated in schizophrenia. We test the hypothesis that schizophrenia differentially impairs DLPFC versus VLPFC control of episodic encoding.

Methods: Cognitive control was manipulated by requiring participants to encode targets and avoid encoding non-targets based upon stimulus properties of test stimuli. The more automatic encoding response (target versus non-target) was predicted to engage VLPFC in both groups. Conversely, having to overcome the prepotent encoding response (non-targets versus targets) was predicted to produce greater DLPFC activation in controls than in patients. Encoding occurred during event-related fMRI in a sample of 21 individuals with schizophrenia and 30 healthy participants. Scanning was followed by recognition testing outside the scanner.

Results: Patients were less successful differentially remembering target versus non-target stimuli, and retrieval difficulties correlated with more severe disorganized symptoms. As predicted, the target versus non-target contrast activated the VLPFC and correlated with retrieval success in both groups. Conversely, the non-target versus target contrast produced greater DLPFC activation in controls than in patients, and DLPFC activation correlated with performance only in controls.

Conclusion: Individuals with schizophrenia can successfully engage the VLPFC to provide control over semantic encoding of individual items, but are specifically impaired at engaging the DLPFC to main context for task-appropriate encoding and thereby generate improved memory for target versus non-target items. This extends previous cognitive control models based on response selection tasks to the memory domain.

Challenges in hemophilia care in Australia and New Zealand

BACKGROUND

Health and life expectancy for people with hemophilia have improved significantly in recent years, but we face new challenges, especially in the context of resource-constrained health services.

AIM

This paper aims to highlight such challenges and propose practical solutions.

METHODS

Nine hemophilia specialists from Australia and New Zealand reached consensus on areas of greatest need for improvement in hemophilia care in these countries, based on clinical experience and published data, and agreed on how to address these.

RESULTS

Demography, optimizing treatment and assessing treatment success were identified as broad areas of challenge which included: comorbidities in ageing patients; transitioning from pediatric to adult care; equity of care for remote populations; weight-based dosing in obese patients; tailoring prophylaxis; accurate diagnosis of acute joint pain; managing chronic arthropathy; providing psychosocial support; consistency in definitions and assessment; and quantifiable outcome measures. Practice points included increased cross-specialty coordination and including psychologists and rheumatologists as part of comprehensive care teams; close collaboration between pediatric and adult centers to facilitate transition of care; systems such as telehealth that ensure continuity of care for remote populations; using pharmacokinetic data to tailor therapy; rapid and accurate diagnosis of acute joint pain; using data from bleeding registries to assess treatment effects and help with service planning; and ensuring consistency through benchmarking and standardization of HTCs.

SUMMARY

Achieving treatment equity, optimal outcomes and cost savings may be possible through investing in national governance structures, expanding the comprehensive model of care and implementing innovative solutions tailored to local needs.

Revision Total Knee Arthroplasty in a Patient with Bilateral Below-the-Knee Amputation: A Case Report

UPDATE

This article was updated on January 27, 2016. The byline, which had previously read "M.G. Williams, MBChB, and J. Phillips, MBBS, FRCS," now reads "M.G. Williams, MBChB, J. Phillips, MBBS, FRCS, and K. Eyres, MD, FRCS(Tr&Orth)." In addition, the name, address, and e-mail address for Dr. Eyres have been added to the address block at the end of the article.An erratum has been published: JBJS Case Connect. 2016 Mar 23;6(1):e22.

CASE

We report the case of a patient with bilateral below-the-knee amputation who had a periprosthetic fracture around a total knee arthroplasty. The fracture was managed with a revision total knee arthroplasty. We discuss the rationale for revision surgery, the surgical techniques, and the postoperative rehabilitation. Follow-up at one year demonstrated maintenance of the pretrauma functional status.

CONCLUSION

In selected patients with a periprosthetic fracture, we believe that revision of a total knee arthroplasty may be considered as an option rather than an above-the-knee amputation or an arthrodesis.

Functional and Neuroanatomic Specificity of Episodic Memory Dysfunction in Schizophrenia: A Functional Magnetic Resonance Imaging Study of the Relational and Item-Specific Encoding Task

IMPORTANCE

Individuals with schizophrenia can encode item-specific information to support familiarity-based recognition but are disproportionately impaired encoding interitem relationships (relational encoding) and recollecting information. The Relational and Item-Specific Encoding (RiSE) paradigm has been used to disentangle these encoding and retrieval processes, which may depend on specific medial temporal lobe (MTL) and prefrontal cortex (PFC) subregions. Functional magnetic resonance (fMRI) imaging during RiSE task performance could help to specify dysfunctional neural circuits in schizophrenia that can be targeted for interventions to improve memory and functioning in the illness.

OBJECTIVES

To use fMRI to test the hypothesis that schizophrenia disproportionately affects MTL and PFC subregions during relational encoding and retrieval relative to item-specific memory processes, and to use fMRI results from healthy individuals serving as controls to establish neural construct validity for RiSE.

DESIGN, SETTING, AND PARTICIPANTS

This multisite, case-control, cross-sectional fMRI study was conducted between November 1, 2010, and May 30, 2012, at 5 Cognitive Neuroscience Test Reliability and Clinical Applications for Schizophrenia sites. The final sample included 52 outpatients with clinically stable schizophrenia and 57 demographically matched healthy control participants. Data analysis was performed between February 1, 2013, and May 30, 2014.

MAIN OUTCOMES AND MEASURES

Behavioral performance speed and accuracy (d') on item recognition and associative recognition tasks. Voxelwise statistical parametric maps for a priori MTL and PFC regions of interest to test activation differences between relational and item-specific memory during encoding and retrieval.

RESULTS

Item recognition was disproportionately impaired in patients with schizophrenia relative to healthy control participants following relational encoding (F1,107 = 4.7; P = .03). The differential deficit was accompanied by reduced dorsolateral PFC activation during relational encoding in patients with schizophrenia compared with healthy control participants (z > 2.3; P < .05 corrected). Retrieval success (hits > misses) was associated with hippocampal activation in healthy control participants during relational item recognition and associative recognition conditions, and hippocampal activation was specifically reduced in schizophrenia for recognition of relational but not item-specific information (z > 2.3; P < .05 corrected).

CONCLUSIONS AND RELEVANCE

In this unique, multisite fMRI study, results in the healthy control group supported RiSE construct validity by revealing expected memory effects in PFC and MTL subregions during encoding and retrieval. Comparison of schizophrenic and healthy control participants revealed disproportionate memory deficits in schizophrenia for relational vs item-specific information, accompanied by regionally and functionally specific deficits in dorsolateral PFC and hippocampal activation.

Current management of fistula-in-ano

Anal fistulae management is a balance of effective healing and the risk of incontinence from sphincter division. This review examines the heterogeneity in the literature of treatment options and the difficulties this presents for surgical training and decision making.

A randomized, placebo-controlled, double-blind study of sapropterin to treat ADHD symptoms and executive function impairment in children and adults with sapropterin-responsive phenylketonuria

Symptoms of attention deficit-hyperactivity disorder (ADHD), particularly inattention, and impairments in executive functioning have been reported in early and continuously treated children, adolescents, and adults with phenylketonuria (PKU). In addition, higher blood phenylalanine (Phe) levels have been correlated with the presence of ADHD symptoms and executive functioning impairment. The placebo-controlled PKU ASCEND study evaluated the effects of sapropterin therapy on PKU-associated symptoms of ADHD and executive and global functioning in individuals who had a therapeutic blood Phe response to sapropterin therapy. The presence of ADHD inattentive symptoms and executive functioning deficits was confirmed in this large cohort of 206 children and adults with PKU, of whom 118 responded to sapropterin therapy. In the 38 individuals with sapropterin-responsive PKU and ADHD symptoms at baseline, sapropterin therapy resulted in a significant improvement in ADHD inattentive symptoms in the first 4 weeks of treatment, and improvements were maintained throughout the 26 weeks of treatment. Sapropterin was well-tolerated with a favorable safety profile. The improvements in ADHD inattentive symptoms and aspects of executive functioning in response to sapropterin therapy noted in a large cohort of individuals with PKU indicate that these symptoms are potentially reversible when blood Phe levels are reduced.

An extremely high-altitude plume seen at Mars' morning terminator

The Martian limb (that is, the observed 'edge' of the planet) represents a unique window into the complex atmospheric phenomena occurring there. Clouds of ice crystals (CO2 ice or H2O ice) have been observed numerous times by spacecraft and ground-based telescopes, showing that clouds are typically layered and always confined below an altitude of 100 kilometres; suspended dust has also been detected at altitudes up to 60 kilometres during major dust storms. Highly concentrated and localized patches of auroral emission controlled by magnetic field anomalies in the crust have been observed at an altitude of 130 kilometres. Here we report the occurrence in March and April 2012 of two bright, extremely high-altitude plumes at the Martian terminator (the day-night boundary) at 200 to 250 kilometres or more above the surface, and thus well into the ionosphere and the exosphere. They were spotted at a longitude of about 195° west, a latitude of about -45° (at Terra Cimmeria), extended about 500 to 1,000 kilometres in both the north-south and east-west directions, and lasted for about 10 days. The features exhibited day-to-day variability, and were seen at the morning terminator but not at the evening limb, which indicates rapid evolution in less than 10 hours and a cyclic behaviour. We used photometric measurements to explore two possible scenarios and investigate their nature. For particles reflecting solar radiation, clouds of CO2-ice or H2O-ice particles with an effective radius of 0.1 micrometres are favoured over dust. Alternatively, the plume could arise from auroral emission, of a brightness more than 1,000 times that of the Earth's aurora, over a region with a strong magnetic anomaly where aurorae have previously been detected. Importantly, both explanations defy our current understanding of Mars' upper atmosphere.

Dutch health-related quality of life measure for chronic otitis media

OBJECTIVE

Chronic otitis media (COM) describes a variety of symptoms and physical findings that result from prolonged damage to the middle ear by infection and inflammation. The Health-Related Quality of Life measure for COM (COMQ-12) is a new questionnaire for the assessment of COM that evaluates the overall burden of disease from the patient's perspective. The aim of this study was to develop and appraise the psychometric properties of the Dutch version of the COMQ-12.

MATERIALS AND METHODS

The Dutch version of the COMQ-12 was obtained through translation and back-translation. Fifty adult patients with a history of active COM completed the Dutch version of the COMQ-12. The internal consistency of this questionnaire was evaluated using Cronbach's alpha coefficient.

RESULTS

The average COMQ-12 score was 22.4 (SD 11.9). The internal consistency of the Dutch version of the COMQ-12 was high, with a Cronbach's alpha value of 0.833.

CONCLUSIONS

The Dutch version of the COMQ-12 provides appropriate health-related quality of life outcome measures in patients with a history of COM. This questionnaire is a useful tool to evaluate the overall burden of disease from the patient's perspective.