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The multi-relay cooperative communication system with improved best relay selection and decode-and-forward (DF) strategy based on directional antenna is investigated. For the mobility of the locations of the relays are essential random, the homogeneous Poisson point process with fixed density are considered. The exact performance expression of outage probability is derived through theoretical deduction. The effects of the Rayleigh fading and the distance attenuation are also considered simultaneously. The accuracy simulations of the relationship between the outage probability and different parameters are carried out. The power allocation between the source node and the relay node is also discussed.

To examine the concordance between testosterone replacement therapy (TRT) use and established reimbursement criteria, as well as compare the persistence of use among available formulations (injectable, oral, topical gel, transdermal patch) among elderly men in Ontario, Canada.We conducted a retrospective cohort study of men aged 66 years or older in Ontario newly treated with testosterone between 1 January 2009 and 31 December 2012 using linked health administrative data. Continuous use was defined on the basis of prescription refills issued within 180 days of the preceding prescription. We studied men who received at least two consecutive TRT prescriptions. We estimated the prevalence of hypogonadism, human immunodeficiency virus, specialist visits and lab tests for serum testosterone prior to initiation of TRT to investigate concordance with prescribing criteria. We also performed a Kaplan-Meier analysis to test for differences in the median time to discontinuation among formulations.Among the 4797 men who received at least two TRT prescriptions, only 38.7% met the reimbursement criteria for use prior to initiating therapy. The median time to discontinuation differed significantly among formulations and was longest among recipients of oral TRT products (383 days), and lower for recipients of topical gels (319 days), injectable (283 days) and transdermal patches (160 days; Log-rank test p 0.001).A large proportion of older men in Ontario do not appear to meet reimbursement criteria prior to commencing therapy, and many discontinue TRT within a year of initiation. Copyright © 2016 John WileySons, Ltd.

Hypoactive BRAF mutants bind more tightly than wild type to the upstream regulator RAS, thus amplifying to amplify ERK signalling; tumours expressing these mutants require coexistent mechanisms for RAS activation to grow and are sensitive to their inhibition. Mutant alleles of the kinase BRAF have been identified in human tumours, some of which have activated catalytic functions, whereas others have impaired or absent kinase activity. Here Neal Rosen and colleagues have characterized the less-understood hypoactive BRAF mutants. They find that these mutants bind more tightly to the upstream regulator RAS in order to amplify signalling and require coexistent mechanisms for RAS activation in the tumour in order to function. The mechanistic action of these hypoactive BRAF mutants is different to that of the activated mutants and dictates their sensitivity to therapeutic inhibitors of the pathway. Elsewhere in this issue, David Santamaria and colleagues show that kinase-inactive BRAF mutants can initiate the development of lung adenocarcinoma in mice. Approximately 200 BRAF mutant alleles have been identified in human tumours. Activating BRAF mutants cause feedback inhibition of GTP-bound RAS, are RAS-independent and signal either as active monomers (class 1) or constitutively active dimers (class 2)1. Here we characterize a third class of BRAF mutants—those that have impaired kinase activity or are kinase-dead. These mutants are sensitive to ERK-mediated feedback and their activation of signalling is RAS-dependent. The mutants bind more tightly than wild-type BRAF to RAS–GTP, and their binding to and activation of wild-type CRAF is enhanced, leading to increased ERK signalling. The model suggests that dysregulation of signalling by these mutants in tumours requires coexistent mechanisms for maintaining RAS activation despite ERK-dependent feedback. Consistent with this hypothesis, melanomas with these class 3 BRAF mutations also harbour RAS mutations or NF1 deletions. By contrast, in lung and colorectal cancers with class 3 BRAF mutants, RAS is typically activated by receptor tyrosine kinase signalling. These tumours are sensitive to the inhibition of RAS activation by inhibitors of receptor tyrosine kinases. We have thus defined three distinct functional classes of BRAF mutants in human tumours. The mutants activate ERK signalling by different mechanisms that dictate their sensitivity to therapeutic inhibitors of the pathway.

Importance Without third-party insurance, access to marketed drugs is limited to those who can afford to pay. We examined this phenomenon in the context of anticoagulation for patients with nonvalvular atrial fibrillation (NVAF). Objective To determine whether, among older Ontarians receiving anticoagulation for NVAF, patients of higher socioeconomic status (SES) were more likely to switch from warfarin to dabigatran prior to its addition to the provincial formulary. Design, Setting and Participants Population-based retrospective cohort study of Ontarians aged 66 years and older, between 2008 and 2012. Exposure Socioeconomic status, as approximated by median neighborhood income. Main Outcomes and Measure We identified two groups of older adults with nonvalvular atrial fibrillation: those who appeared to switch from warfarin to dabigatran after its market approval but prior to its inclusion on the provincial formulary (“switchers”), and those with ongoing warfarin use during the same interval (“non-switchers”). Results We studied 34,797 patients, including 3183 “switchers” and 31,614 “non-switchers”. We found that higher SES was associated with switching to dabigatran prior to its coverage on the provincial formulary (p

Background. There are no Canadian prevalence studies on pulmonary arterial hypertension (PAH) to date. We described the characteristics of treated PAH patients and the healthcare utilization and costs associated with PAH in a population of public drug plan beneficiaries in Ontario, Canada.Methods. A retrospective cross-sectional analysis was conducted between April 2010 and March 2011 to identify treated PAH patients using population-based health administrative databases. We investigated demographic and clinical characteristics of treated PAH patients and conducted a cohort study to determine treatment patterns, healthcare utilization, and associated costs, over a one-year follow-up period (March 2012).Results. We identified 326 treated PAH cases in Ontario’s publicly funded drug plan. Overall mean age was 59.4 years (±20.3 years) and over 77% of cases were women (n=251). Combination therapy was used to treat 22.9% (n=69) of cases, costing an average of $4,569 (SD $1,544) per month. Median monthly healthcare costs were $264 (IQR $96–$747) for those who survived and $2,021 (IQR $993–$6,399) for those who died over a one-year period, respectively (p<0.01).Conclusions. PAH care in Ontario is complex and has high healthcare costs. This data may help guide towards improved patient management.

Bridging Model is a versatile micromechanical theory, which can be used to simulate nonlinear behavior and ultimate strength of a laminated composite. The application of the Bridging Model requires input data of the in-situ mechanical properties of its constituents. A previous research has shown that the in-situ transverse strength of the matrix is equal to the pure matrix strength divided by a stress concentration factor along that direction. The stress concentration factor therein, however, was obtained based on a perfect bonding assumption between the fiber and the matrix. In this paper, a more general case is concerned. Namely, an interface layer is assumed to exist between the fiber and the matrix. Explicit expression for the stress concentration factor with an imperfect fiber and matrix interface bonding is obtained. The effect of the interface layer on the stress concentration factor is discussed.

Purpose Conflicting evidence exists regarding the association between antidepressant use and reinfarction among high-risk cardiovascular patients. Recent evidence suggests that clinical benefit associated with antidepressants may be related to serotonergic activity, suggesting that some antidepressants may offer greater advantages than others. Methods We conducted a population-based nested case–control study among patients aged 66 years or older who commenced clopidogrel between April 1, 2002 and December 31, 2009, following hospital discharge for acute myocardial infarction (AMI). Cases were those who were readmitted for AMI, underwent percutaneous coronary intervention (PCI), or died within 90 days of discharge. Three controls were matched to each case on age, PCI, and the date of hospital discharge. We categorized exposure to antidepressants as current or no use within 120 days before the index date, and the serotonergic activity of antidepressants was further categorized as low, medium, and high according to their affinity for the serotonin transporter. Results Among 24 090 patients who received clopidogrel following AMI, we identified 2494 cases. Of these, 2444 (98%) were successfully matched to 7045 controls. After extensive multivariable adjustment, antidepressant use was not associated with lower risk of the composite outcome (adjusted odds ratio [OR] 1.11 and 95% confidence interval [CI] 0.98–1.27). The absence of association was consistent across the different antidepressant groups categorized by serotonin transporter affinity. Conclusion In high-risk cardiovascular patients with a history of AMI and treated with clopidogrel, antidepressant use is associated with no additional reduction in risk of reinfarction irrespective of serotonin transporter affinity. Copyright © 2012 John Wiley & Sons, Ltd.

In allusion to the problems such as the poor flatness of the parts , not-easy-guaranteed aperture precision, low strength and short service life of mould that occur in stamping production of the screen hole parts, this article detailed introduced the diamond punching method and at the same time it summarized the maintenance of the mould that this method uses

Aims To determine the extent to which other opioids are prescribed to patients receiving methadone in Ontario, Canada. Design Retrospective cohort study. Setting Ontario, Canada from 1 April 2003 to 31 March 2010. Participants We studied patients aged 15-64 years with publically funded drug coverage who received at least 30 days of continuous methadone maintenance therapy (MMT). Measurements The proportion of patients who received more than 7 days of a non-methadone opioid during MMT. A secondary analysis examined the extent to which non-methadone opioids were prescribed by physicians or dispensed by pharmacies not involved in a patient's MMT. Findings Among 18 759 patients treated with methadone, 3456 (18.4%) received at least one prescription for non-methadone opioids of more than 7 days' duration. In this group, the median number of non-methadone opioid prescriptions dispensed per year was 11.9 (interquartile range 4.1-25.0). The most frequently prescribed opioids were codeine and oxycodone. Of the 73 520 non-methadone opioid prescriptions of more than 7 days' duration, nearly half (45.8%) originated from non-MMT prescribers and pharmacies. Conclusions Many patients receiving methadone maintenance therapy in Ontario receive overlapping prescriptions for other opioids, often for extended periods. The associated prescribing patterns suggest that many such prescriptions may be duplicitous. The prescribing and dispensing of non-methadone opioids to patients receiving methadone maintenance therapy is likely to be observed in jurisdictions outside Ontario, Canada.

To obtain the ultraweak luminescence properties of plant affected by multilateral growth,environment factors of osmanthus tree seedings were used as the research material.Quadratic rotation-orthogonal composite experimental design was used to study the effects of illumination,temperature,relative humidity,and moisture on the ultra-weak luminescence of leaves of osmanthus tree seedings.The model of four environmental factors to ultra-weak luminescence of osmanthus tree seedings leaves was established.The ANOVA(analysis of variance) analysis showed that the significant value of influence of different factors and their interaction on ultra-weak luminescence are different.The linear effects of four variables,the quadratic effects of illumination,relative humidity and moisture,and the interaction effects of illumination moisture and temperature relative humidity are all significant,with p-value ≤0.01.And when light by 10 stick of lamp tube(intensity of illumination value 4 229 Lx) and mean temperature,humidity and water respectively controlling in 35 ℃ 90 mL/d,85%,the value of ultraweak luminescence was maximum.Based on that,the influence rule of each influential environmental factors and their interactions on the ultra-weak luminescence was also included.

Genomic studies have linked mTORC1 pathway-activating mutations with exceptional response to treatment with allosteric inhibitors of mTORC1 called rapalogs. Rapalogs are approved for selected cancer types, including kidney and breast cancers. Here, we used sequencing data from 22 human kidney cancer cases to identify the activating mechanisms conferred by mTOR mutations observed in human cancers and advance precision therapeutics. mTOR mutations that clustered in focal adhesion kinase targeting domain (FAT) and kinase domains enhanced mTORC1 kinase activity, decreased nutrient reliance, and increased cell size. We identified 3 distinct mechanisms of hyperactivation, including reduced binding to DEP domain-containing MTOR-interacting protein (DEPTOR), resistance to regulatory associated protein of mTOR-mediated (RAPTOR-mediated) suppression, and altered kinase kinetics. Of the 28 mTOR double mutants, activating mutations could be divided into 6 complementation groups, resulting in synergistic Rag- and Ras homolog enriched in brain-independent (RHEB-independent) mTORC1 activation. mTOR mutants were resistant to DNA damage-inducible transcript 1-mediated (REDD1-mediated) inhibition, confirming that activating mutations can bypass the negative feedback pathway formed between HIF1 and mTORC1 in the absence of von Hippel-Lindau (VHL) tumor suppressor expression. Moreover, VHL-deficient cells that expressed activating mTOR mutants grew tumors that were sensitive to rapamycin treatment. These data may explain the high incidence of mTOR mutations observed in clear cell kidney cancer, where VHL loss and HIF activation is pathognomonic. Our study provides mechanistic and therapeutic insights concerning mTOR mutations in human diseases.

The hydration ZrOH was loaded in the powdered activated carbon（PAC）,the aim to modify activated carbon, then the mixed liquor including poval(PVA) and sodium alginate tech grade (SV) , as the embedding agent ,embedded the modified PAC.The main investigation were that the hydration ZrOH concentration,the ratio of embedding agent composition and Curing liquid ingredient etc. influence the phosphorus removal . The orthogonal experiment determined the optimum prepared conditions of embedding adsorbent. The experimental results showed that : the optimum loaded conditions were that PAC average particle size was 0.5-1.0mm, hydration ZrOH concentration was 0.04mol/L;the optimum embedded preparation conditions were PVA mass concentration for 8%，SV mass concentration for 1.2%; the optimum cured conditions were the curing liquid ingredient was saturated boric acid with 2% CaCl2. The adsorption of phosphorus removal efficiency was 99.27%.

6 Background: Emergency department (ED) visits and hospitalizations are undesirable and costly. We developed and validated the PROACCT (PRediction Of Acute Care use during Cancer Treatment) score to predict at least one acute care visit during the first 30 days (AC30) after initiating systemic therapy for cancer. Methods: Using administrative data, we identified patients in Ontario with the 18 most common solid tumors who started systemic treatment from July 1, 2014 to June 30, 2015. Southwestern and Northeastern Ontario formed the development and validation cohorts, respectively. We created a score to predict AC30 using multivariate logistic regression in the development cohort. Combinations of tumor sites and regimens were grouped into quintiles based on AC30. The score was assessed in the validation cohort. Results: AC30 occurred in 23% (4438/19359) of patients. Eleven factors predicted AC30 and formed the score: tumor site and regimen (2nd quintile: 2; 3rd-4th: 3; 5th: 4), recent ED visit (2), recent palliative radiation (1), rural residence (1) and Edmonton Symptom Assessment Scale anxiety (4+: 1), lack of appetite (4+: 1), pain (4+: 1), and wellbeing (4+: 1). Among the 204 tumor-regimen combinations, tumors with poor prognoses, such as pancreatic and lung, and platinum- and taxane-containing regimens, carried the highest risk for AC30. The score had moderate discrimination (c-statistic 0.65; P< 0.001) and strong calibration (Table) in the validation cohort. Conclusions: PROACCT identifies factors that predict AC30 in patients starting systemic treatment for solid tumors and could be incorporated into electronic health records to select patients for preventative interventions. [Table: see text]

BRAF V600E hyperactivates ERK and signals as an RAF inhibitor-sensitive monomer. While RAF inhibitors can produce impressive clinical responses in patients with mutant BRAF tumors, the mechanisms of resistance to these drugs are incompletely characterized. Here, we report a complete response followed by clinical progression in a patient with a BRAF V600E-mutant brain tumor treated with dabrafenib. Whole-exome sequencing revealed a secondary BRAF L514V mutation at progression that was not present in the pretreatment tumor. Expressing BRAF V600E L514V induces ERK signaling, promotes RAF dimer formation, and is sufficient to confer resistance to dabrafenib. A novel class of RAF dimer inhibitors and an ERK inhibitor are effective against BRAF L514V-mediated resistance. Collectively, our results validate a novel biochemical mechanism of RAF inhibitor resistance mediated by a secondary mutation, emphasizing that like driver mutations in cancer, the spectrum of mutations that drive resistance to targeted therapy are heterogeneous and perhaps emerge with a lineage-specific prevalence. Citation Format: Jiawan Wang, Zhan Yao, Philip Jonsson, Amy Allen, Alice Can Ran Qin, Sharmeen Uddin, Ira J. Dunkel, Mary Petriccione, Katia Manova, Sofia Haque, Marc Rosenblum, David J. Pisapia, Neal Rosen, Barry S. Taylor, Christine A. Pratilas. A secondary mutation in BRAF confers resistance to RAF inhibition in a BRAF V600E-mutant brain tumor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3184.

Nucleophosmin/B23, an abundant nucleolar protein, plays multiple roles in cell growth and proliferation, and yet, little has been studied about its function in regulating dynamics of microtubules. Here, we report that B23 directly interacts with Eg5, a member of the kinesin family, in the cytosol. The DNA/RNA binding domain of B23 and the motor domain of Eg5 were found to be involved in their interaction. Both in vivo and in vitro evidences showed that B23 acts as an upstream regulator of Eg5 in promoting microtubule polymerization. Moreover, we further demonstrated that B23 regulates microtubule dynamics by directly inhibiting Eg5 ATPase activity.

10014Background: AYA cancer survivors are at elevated risk for developing therapy-related adverse health outcomes and require life-long risk-adapted health care. We determined the location and prov...

BRAF V600E drives tumors by hyperactivating ERK signaling, is activated in a RAS-independent manner, and signals as a monomer. Selective inhibitors of RAF potently inhibit BRAF V600E and downstream ERK signaling, and have been associated with impressive clinical responses in patients whose tumors harbor V600E mutations in BRAF. Almost all patients, however, ultimately develop resistance. To date, acquired resistance mechanisms validated in patient samples have included splice forms of BRAF, mutations in NRAS, and BRAF amplification, all of which promote formation of RAF dimers, and mutations in MEK. Second-site point mutations in BRAF that promote dimer formation and are associated with acquired resistance have not previously been identified in RAF inhibitor-resistant tumors. Here, we report a complete response followed by clinical progression of a BRAF V600E-mutant pediatric brain tumor treated with the RAF inhibitor dabrafenib. We identified a second-site mutation in BRAF at the time of progression that was not present in the pretreatment tumor. Further study indicated the acquired mutation is in cis with V600E. We demonstrate that the acquired resistance mutation induces RAF dimer formation, and is sufficient to confer resistance to dabrafenib. Moreover, we showed that ERK signaling activated by the double mutation is sensitive to MEK inhibition or to the RAF plus and MEK inhibitor combination. We also find that two novel RAF dimer inhibitors may overcome resistance mediated by the novel mutation in BRAF. This is the first study, to our knowledge, that demonstrates the emergence of a confirmed second-site mutation in BRAF V600E and validates that this mutation is responsible for acquired resistance in an initially responding patient treated with dabrafenib. The mechanism of acquired resistance can be abrogated by the novel RAF dimer inhibitors. Our data confirm that a novel class of RAF dimer inhibitors are active against an acquired resistance mutation, suggesting an improved personalized treatment option for patients who harbor similar second-site mutations in BRAF. Citation Format: Jiawan Wang, Zhan Yao, Philip Jonsson, Amy Allen, Alice Can Ran Qin, David Pisapia, Neal Rosen, Barry S. Taylor, Christine A. Pratilas. A second-site mutation in BRAF confers resistance to RAF inhibition in a BRAF V600E-mutant brain tumor [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A129.

The nucleolus is one of the functional nuclear compartments in which the ribosome biogenesis takes place. Proteomic analysis revealed a large number of nucleolar proteins that are involved in diverse cellular processes, including biogenesis of ribonucleoprotein particles, stress responses, cell proliferation and cell cycle progression. Here, we report that in response to transcription repression-induced nucleolar segregation, B23, a nucleolar protein required for rRNA processing, is localized to the cytoplasm and forms a complex with the mRNA-binding proteins hnRNPU and hnRNPA1 in a sequential manner. In addition, RNA Polymerase I, but not RNA Polymerase II inhibition, was found to account for the translocation-dependent assembly of B23/hnRNPU/hnRNPA1. We also showed that interactions among these proteins are regulated by hnRNPU-bound mRNAs such as the 3'-untranslated region (UTR) of Bcl-xL mRNA. Ectopically expressed 3'-UTR of Bcl-xL mRNA, which disrupted the interactions among B23, hnRNPU and hnRNPA1, led to enhanced cell apoptosis induced by either actinomycin D treatment or mitotic arrest. Overall, these data highlight a novel function of B23 as a stress sensor in the assembly of B23/hnRNPU/hnRNPA1 complex to promote cell survival.

Intermediate filaments (IFs) provide crucial structural support in higher eukaryotic cells. Accumulating evidences show that IFs also participate in various cellular activities including stress responses, cell growth, cell death and cell migration through dynamic interactions with various non-structure proteins. Here we report the identification of Pirh2, a RING-H2-type ubiquitin E3 ligase, as a novel binding partner of the cytoplasmic IF proteins keratin 8/18 (K8/18). Phosphorylation of either Pirh2 or K8/18 affects their association. Although Pirh2 was not found to influence the stability of K8/18, it displayed an unexpected role in regulating the organization of the network of K8/18 keratin filaments. Disruption of Pirh2-K8/K18 interaction by either UV irradiation or knockdown with Pirh2 or K18 led to the aggregation of K8/18 keratin filaments. It further induced mitochondrial redistribution, and this process is likely through a microtubule-mediated pathway. The abnormal localization of mitochondria in Pirh2-knockdown cells may partially account for its increased cell sensitivity to UV-induced apoptosis, probably through enhancing the release of pro-apoptotic proteins, such as cytochrome c and Smac/DIABLO to the cytosol. Overall, our data reveal the novel role of the Pirh2-K8/18 complex in governing the distribution of mitochondria.

FlexRay is a communication protocol that combines event- and time-triggered communication to increase the schedulability and flexibility of message scheduling in current car systems. Because safety and reliability are particularly crucial for automotive systems, the worst-case response times of signals transmitted by electronic control units must be under their deadlines. To increase the bandwidth utilization, the slotmultiplexing (SM) mechanism that is allowable in protocol specification was adopted to schedule messages offline in the dynamic segment of the FlexRay protocol, and this mechanism was also considered in the timing analysis. The proposed method was feasible to calculate worst-case response time of message under any bus load when considered slot-multiplexing. Then the approach was applied to a Society of Automotive Engineers benchmark to ensure that all messages were schedulable. The simulation results revealed that by using slot-multiplexing, only 17 identifiers were used, which was less than 23 identifiers that were needed when the slot-multiplexing was not considered. It also improved the schedulability of dynamic segment with up to 27% improvement in bus bandwidth utilization.

Purpose No effective systemic therapy exists for patients with metastatic low-grade serous (LGS) ovarian cancers. BRAF and KRAS mutations are common in serous borderline (SB) and LGS ovarian cancers, and MEK inhibition has been shown to induce tumor regression in a minority of patients; however, no correlation has been observed between mutation status and clinical response. With the goal of identifying biomarkers of sensitivity to MEK inhibitor treatment, we performed an outlier analysis of a patient who experienced a complete, durable, and ongoing (> 5 years) response to selumetinib, a non-ATP competitive MEK inhibitor. Patients and Methods Next-generation sequencing was used to analyze this patient's tumor as well as an additional 28 SB/LGS tumors. Functional characterization of an identified novel alteration of interest was performed. Results Analysis of the extraordinary responder's tumor identified a 15-nucleotide deletion in the negative regulatory helix of the MAP2K1 gene encoding for MEK1. Functional characterization demonstrated that this mutant induced extracellular signal-regulated kinase pathway activation, promoted anchorage-independent growth and tumor formation in mice, and retained sensitivity to selumetinib. Analysis of additional LGS/SB tumors identified mutations predicted to induce extracellular signal-regulated kinase pathway activation in 82% (23 of 28), including two patients with BRAF fusions, one of whom achieved an ongoing complete response to MEK inhibitor–based combination therapy. Conclusion Alterations affecting the mitogen-activated protein kinase pathway are present in the majority of patients with LGS ovarian cancer. Next-generation sequencing analysis revealed deletions and fusions that are not detected by older sequencing approaches. These findings, coupled with the observation that a subset of patients with recurrent LGS ovarian cancer experienced dramatic and durable responses to MEK inhibitor therapy, support additional clinical studies of MEK inhibitors in this disease.

Histiocytic neoplasms are clonal, hematopoietic disorders characterized by an accumulation of abnormal, monocyte-derived dendritic cells or macrophages in Langerhans cell histiocytosis (LCH) and non-Langerhans cell histiocytosis (non-LCH), respectively. The discovery of BRAFV600E mutations in approximately 50% of these patients provided the first molecular therapeutic target in histiocytosis. However, recurrent driving mutations in the majority of patients with BRAFV600E–wild-type non-LCH are unknown, and recurrent cooperating mutations in non-MAP kinase pathways are undefined for the histiocytic neoplasms. Through combined whole-exome and transcriptome sequencing, we identified recurrent kinase fusions involving BRAF, ALK, and NTRK1, as well as recurrent, activating MAP2K1 and ARAF mutations in patients with BRAFV600E–wild-type non-LCH. In addition to MAP kinase pathway lesions, recurrently altered genes involving diverse cellular pathways were identified. Treatment of patients with MAP2K1- and ARAF-mutated non-LCH using MEK and RAF inhibitors, respectively, resulted in clinical efficacy, demonstrating the importance of detecting and targeting diverse kinase alterations in these disorders. Significance: We provide the first description of kinase fusions in systemic histiocytic neoplasms and activating ARAF and MAP2K1 mutations in non-Langerhans histiocytic neoplasms. Refractory patients with MAP2K1- and ARAF-mutant histiocytoses had clinical responses to MEK inhibition and sorafenib, respectively, highlighting the importance of comprehensive genomic analysis of these disorders. Cancer Discov; 6(2); 154–65. ©2015 AACR. This article is highlighted in the In This Issue feature, p. 109

Summary ERK signaling requires RAS-induced RAF dimerization and is limited by feedback. Activated BRAF mutants evade feedback inhibition of RAS by either of two mechanisms. BRAF V600 mutants are activated monomers when RAS activity is low; all other activating BRAF mutants function as constitutive RAS-independent dimers. RAF inhibitors effectively inhibit mutant monomers, but not dimers; their binding to one site in the dimer significantly reduces their affinity for the second. Tumors with non-V600E BRAF mutants are insensitive to these drugs, and increased expression of BRAF V600E dimers causes acquired resistance. A compound that equally inhibits both sites of mutant RAF dimers inhibits tumors driven by either class of mutants or those BRAF V600E tumors with dimer-dependent acquired resistance to monomer-specific inhibitors.

The aim of this study was to investigate the safety and efficacy of a heparin drug delivery system (HEP DDS) for prevention of posterior capsular opacification (PCO) in rabbits.Fifty New Zealand albino rabbits (50 eyes) undergoing phacoemulsification were equally divided into five groups receiving normal saline eye drops (group A), a carrier DDS implanted into the posterior chamber (group B), 5% heparin eye drops (group C), a HEP DDS implanted subconjunctivally (group D) and a HEP DDS implanted into the posterior chamber (group E). All the 50 eyes were examined by slit-lamp microscopy. The heparin levels in blood and aqueous humor were measured, and the wet posterior capsules were weighed.All eyes in groups A and B had PCO at 5-7 days, much earlier than in groups C, D and E. Two eyes in group C, three eyes in group D and six eyes in group E showed no signs of PCO throughout the 12-week study. The mean weight of wet posterior capsules from groups A-E was 157.919 mg, 160.091 mg, 81.114 mg, 71.827 mg and 19.984 mg respectively. The mean aqueous humor heparin level in groups C, D and E was 10.279 microg/ml, 13.246 microg/ml and 25.964 microg/ml respectively. Cell proliferation of the posterior capsules in group E was not active. The conjunctiva, cornea, iris, ciliary body and retina remained intact, and no significant toxic reactions were observed. No intraocular hemorrhage occurred during the follow-up.Implantation of a HEP DDS into the posterior chamber of experimental animals significantly maintained a higher heparin level in aqueous humor for a relatively long period of time. The findings indicate potential prevention of PCO with minimum toxic and side effects.

Activating BRAF mutants drive human tumors by dysregulating ERK signaling despite ERK-dependent feedback suppression of RAS. These RAF mutants become RAS independent, by either of two mechanisms, and they are thus unaffected by feedback inhibition of upstream signaling. Recently, it has become clear that mutation activation of MEK1 or MEK2 occur at appreciable frequency in human tumors, but the mechanism of activation of these mutants and whether they remain dependent on upstream activation of RAS or RAF signaling remains unknown. Here we characterized the mechanism of activation of 18 recurrent MEK1 mutants identified in human cancer. Based on these data, they fall into three classes. The kinase activity of first class remains dependent on RAF mediated phosphorylation of S218 and S222; the second class of MEK mutants has basal RAF-independent activity, but can be further stimulated by RAF and the third class no longer requires phosphorylation of S218 and S222 and signals in a RAF independent manner. These features determined their sensitivity to ERK-dependent feedback regulation and the ability to drive ERK signaling output in cells. The more RAF-independent activity the mutants acquired, the better they could activate downstream ERK pathway, leading to increased transforming activities in MEF cells in the absence of RAF. This is consistent with their genetic association with RAS, RAF and NF1 mutations in human tumors. The Class 3 RAF-independent MEK1 mutants tend to be mutually exclusive with those mutants, while coexistence with RAS/RAF/NF1 mutations is frequently observed in tumors with Class 1 or 2 MEK1 mutants. Moreover, functional class correlated with sensitivities of ERK signaling driven by these mutants to MEK inhibitors that function by different mechanisms. Unlike RAF dependent or regulated MEK1 mutants, the ERK signaling driven by RAF independent MEK1 mutants is insensitive to an allosteric MEK inhibitor that functions by preventing RAF mediated MEK phosphorylation. However, signaling driven by all classes of MEK1 mutants is sensitive to an ATP competitive MEK1 inhibitor which targets MEK1 kinase activity. Citation Format: Yijun Gao, Matthew T. Chang, Daniel McKay, Rona D. Yaeger, Merna Torres, Keven Muniz, Drosten Matthias, Omar I. Abdel-Wahab, Mariano Barbacid, Giordano Caponigro, Darrin Stuart, David Solit, Barry S. Taylor, Zhan Yao, Neal Rosen. Activation mechanisms of cancer associated MEK1 mutants [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 395. doi:10.1158/1538-7445.AM2017-395

Approximately two hundred mutant BRAF alleles have been identified in human tumors. Physiologic activation of RAF isoforms requires RAS-dependent induction of their dimerization. Activating BRAF mutants cause ERK dependent feedback inhibition of RAS.GTP and are RAS independent. As we have shown previously, they signal either as active monomers or RAS-independent constitutively active dimers. Here, we characterized a third class of BRAF mutants—those that have impaired kinase activity or are kinase dead. These class 3 BRAF mutants are sensitive to ERK-mediated feedback and they function in a RAS-dependent manner. In tumors, they bind more tightly to active RAS, thus enhancing their heterodimerization with CRAF. This is associated with the amplification of RAS-RAF-MEK-ERK signaling. Since these mutants are sensitive to ERK-dependent feedback inhibition of RAS, their enhancement of ERK signaling in tumors requires concurrent dysregulation of RAS activation. Thus, melanomas with Class 3 mutations usually harbor coexistent RAS mutation or NF1 mutants/deletion, whereas receptor tyrosine kinase signaling is activated in lung and colorectal cancers with these mutants. Our model suggests that these tumors will be sensitive to the inhibition of RAS activation. Currently, no direct inhibitors of RAS activation are available. However, in support of this idea, inhibitors of activated RTK signaling in carcinomas with Class 3 BRAF mutants and wild type RAS is sufficient to markedly inhibit ERK signaling and their growth in in vivo murine models and in patients. We have thus defined a third subset of BRAF mutants, which is RAS-dependent. Tumors harboring such mutants are sensitive to tyrosine kinase inhibitors in tumors expressing wild type RAS and NF1. Citation Format: Zhan Yao, Rona Yaeger, Vanessa S. Rodrik-Outmezguine, Anthony Tao, Neilawattie M. Torres, Matthew T. Chang, Matthias Drosten, Huiyong Zhao, Fabiola Cecchi, Todd Hembrough, Judith Michels, Hervé Baumert, Linde Miles, Naomi M. Campbell, Elisa de Stanchina, David B. Solit, Mariano Barbacid, Barry S. Taylor, Neal Rosen. Tumors with class 3 BRAF mutants are sensitive to the inhibition of activated RAS [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4078. doi:10.1158/1538-7445.AM2017-4078

BACKGROUND: Dabigatran etexilate is a prodrug whose absorption is opposed by intestinal P-glycoprotein and which is converted by carboxylesterase to its active form, dabigatran. Unlike other statins, simvastatin and lovastatin are potent inhibitors of P-glycoprotein and carboxylesterase, and might either increase the risk of hemorrhage with dabigatran etexilate or decrease its effectiveness. METHODS: We conducted 2 population-based, nested case–control studies involving Ontario residents 66 years of age and older who started dabigatran etexilate between May 1, 2012, and Mar. 31, 2014. In the first study, cases were patients with ischemic stroke; in the second, cases were patients with major hemorrhage. Each case was matched with up to 4 controls by age and sex. All cases and controls received a single statin in the 60 days preceding the index date. We determined the association between each outcome and the use of simvastatin or lovastatin, relative to other statins. RESULTS: Among 45 991 patients taking dabigatran etexilate, we identified 397 cases with ischemic stroke and 1117 cases with major hemorrhage. After multivariable adjustment, use of simvastatin or lovastatin was not associated with an increased risk of stroke (adjusted odds ratio [OR] 1.33, 95% confidence interval [CI] 0.88 to 2.01). In contrast, use of simvastatin and lovastatin were associated with a higher risk of major hemorrhage (adjusted OR 1.46, 95% CI 1.17 to 1.82). INTERPRETATION: In patients receiving dabigatran etexilate, simvastatin and lovastatin were associated with a higher risk of major hemorrhage relative to other statins. Preferential use of the other statins should be considered in these patients.

This paper introduces blanking, drawing and compound die of the cylindrical parts. The compound die applies the special structure to maintain a constant blank holder pressure, which is not increased by drawing. It reduces the processes and improves the efficiency of production.

In existent reference material on stamping, a range of application of the calculating formula of shearing force of die of inclined edge is not limited. This gives rise to misunderstanding very easily. Now this paper from different points of view just analyses and discusses the Calculation method for shearing force with different rake angle of inclined edge, so it is very practical and significant.

Although much is known about the underlying mechanisms of p53 activity and regulation, the factors that influence the diversity and duration of p53 responses are not well understood. Here we describe a unique mode of p53 regulation involving alternative splicing of the TP53 gene. We found that the use of an alternative 3' splice site in intron 6 generates a unique p53 isoform, dubbed p53 Psi. At the molecular level, p53. is unable to bind to DNA and does not transactivate canonical p53 target genes. However, like certain p53 gain-of-function mutants, p53. attenuates the expression of E-cadherin, induces expression of markers of the epithelial-mesenchymal transition, and enhances the motility and invasive capacity of cells through a unique mechanism involving the regulation of cyclophilin D activity, a component of the mitochondrial inner pore permeability. Hence, we propose that p53. encodes a separation-of-function isoform that, although lacking canonical p53 tumor suppressor/transcriptional activities, is able to induce a prometastatic program in a transcriptionally independent manner.

Guidance regarding appropriate and cost-effective use of prescription drugs is published in the Ontario Drug Benefit Formulary in the form of “therapeutic notes.” We conducted a cross-sectional study of all residents of Ontario aged 66 and older who received a new prescription for one of two drugs, aliskiren or sitagliptin, between December 1, 2008 and March 31, 2012 to determine how frequently such guidance is followed. Approximately half of initial prescriptions for aliskiren and sitagliptin were prescribed in a manner that did not conform to the therapeutic note recommendations (51.4% and 49.3%, respectively). Given this high rate of non-conformance, policy makers may wish to use other mechanisms to influence prescriber behaviour to improve the quality and efficiency of healthcare.

A new watermarking algorithm based on new-defined characters using TrueType for Microsoft Word documents is proposed. In this algorithm, new-defined characters generated by TrueType function are used as a watermark, and this watermark is embedded into the host Microsoft Word document according to some rules. We simulated this algorithm by C++ language, and the experimental results showed that this algorithm has completely imperceptibility, high robustness against many kinds of attacks and can locate the tamper locations. The proposed algorithm can be used in the copyright protection for Microsoft Word documents.

Melanoma is a disease characterized by lesions that activate ERK. Although 70% of cutaneous melanomas harbor activating mutations in the BRAF and NRAS genes, the alterations that drive tumor progression in the remaining 30% are largely undefined. Vemurafenib, a selective inhibitor of RAF kinases, has clinical utility restricted to BRAF-mutant tumors. MEK inhibitors, which have shown clinical activity in NRAS-mutant melanoma, may be effective in other ERK pathway-dependent settings. Here, we investigated a panel of melanoma cell lines wild type for BRAF and NRAS to determine the genetic alteration driving their transformation and their dependence on ERK signaling in order to elucidate a candidate set for MEK inhibitor treatment. A cohort of the BRAF/RAS wild type cell lines with high levels of RAS-GTP had loss of NF1, a RAS GTPase activating protein. In these cell lines, the MEK inhibitor PD0325901 inhibited ERK phosphorylation, but also relieved feedback inhibition of RAS, resulting in induction of pMEK and a rapid rebound in ERK signaling. In contrast, the MEK inhibitor trametinib impaired the adaptive response of cells to ERK inhibition, leading to sustained suppression of ERK signaling and significant antitumor effects. Notably, alterations in NF1 frequently co-occurred with RAS and BRAF alterations in melanoma. In the setting of BRAF(V600E), NF1 loss abrogated negative feedback on RAS activation, resulting in elevated activation of RAS-GTP and resistance to RAF, but not MEK, inhibitors. We conclude that loss of NF1 is common in cutaneous melanoma and is associated with RAS activation, MEK-dependence, and resistance to RAF inhibition. Cancer Res; 74(8); 2340–50. ©2014 AACR.

The effects of selective phosphoinositide 3-kinase (PI3K) and AKT inhibitors were compared in human tumor cell lines in which the pathway is dysregulated. Both caused inhibition of AKT, relief of feedback inhibition of receptor tyrosine kinases, and growth arrest. However, only the PI3K inhibitors caused rapid induction of cell death. In seeking a mechanism for this phenomenon, we found that PI3K inhibition, but not AKT inhibition, causes rapid inhibition of wild-type RAS and of RAF–MEK–ERK signaling. Inhibition of RAS–ERK signaling is transient, rebounding a few hours after drug addition, and is required for rapid induction of apoptosis. Combined MEK and AKT inhibition also promotes cell death, and in murine models of HER2+ cancer, either pulsatile PI3K inhibition or combined MEK and AKT inhibition causes tumor regression. We conclude that PI3K is upstream of RAS and AKT and that pulsatile inhibition of both pathways is sufficient for effective antitumor activity. Significance: We show that the RAS–ERK pathway is a key downstream effector pathway of oncogenic PI3K. Coordinate downregulation of AKT and ERK is necessary for induction of apoptosis and antitumor activity and can be accomplished with pulsatile dosing, which will likely decrease toxicity and allow administration of therapeutic doses. Cancer Discov; 4(3); 334–47. ©2014 AACR. This article is highlighted in the In This Issue feature, p. 259

Background: Telmisartan, unlike other angiotensin-receptor blockers, is a partial agonist of peroxisome proliferator–activated receptor-γ, a property that has been associated with improvements in surrogate markers of cardiovascular health in small trials involving patients with diabetes. However, whether this property translates into a reduced risk of cardiovascular events and death in these patients is unknown. We sought to explore the risk of myocardial infarction, stroke and heart failure in patients with diabetes who were taking telmisartan relative to the risk of these events occurring in patients taking other angiotensin-receptor blockers. Methods: We conducted a population-based, retrospective cohort study of Ontario residents with diabetes aged 66 years and older who started treatment with candesartan, irbesartan, losartan, telmisartan or valsartan between Apr. 1, 2001, and Mar. 31, 2011. Our primary outcome was a composite of admission to hospital for acute myocardial infarction, stroke or heart failure. We examined each outcome individually in secondary analyses, in addition to all-cause mortality. Results: We identified 54 186 patients with diabetes who started taking an angiotensin-receptor blocker during the study period. After multivariable adjustment, patients who took either telmisartan (adjusted hazard ratio [HR] 0.85, 95% confidence interval [CI] 0.74–0.97) or valsartan (adjusted HR 0.86, 95% CI 0.77–0.95) had a lower risk of the composite outcome compared with patients who took irbesartan. In contrast, no significant difference in risk was seen between other angiotensin-receptor blockers and irbesartan. In secondary analyses, we found a reduced risk of admission to hospital for heart failure with telmisartan compared with irbesartan (adjusted HR 0.79, 95% CI 0.66–0.96), but no significant differences in risk were seen between angiotensin-receptor blockers in our other secondary analyses. Interpretation: Compared with other angiotensin-receptor blockers, telmisartan and valsartan were both associated with a lower risk of admission to hospital for acute myocardial infarction, stroke or heart failure among older adults with diabetes and hypertension. Telmisartan and valsartan may therefore be the preferred angiotensin-receptor blockers for use in these patients.

Background Some evidence suggests that chlorthalidone may be superior to hydrochlorothiazide for the treatment of hypertension. Objective To compare the effectiveness and safety of chlorthalidone and hydrochlorothiazide in older adults. Design Propensity score-matched observational cohort study with up to 5 years of follow-up. Setting Ontario, Canada. Patients All individuals aged 66 years or older who were newly treated with chlorthalidone or hydrochlorothiazide and were not hospitalized for heart failure, stroke, or myocardial infarction in the prior year were eligible for inclusion. Each chlorthalidone recipient was matched to up to 2 hydrochlorothiazide recipients on the basis of age, sex, year of treatment initiation, and propensity score. Measurements The primary outcome was a composite of death or hospitalization for heart failure, stroke, or myocardial infarction. Safety outcomes included hospitalization with hypokalemia or hyponatremia. Results A total of 29 873 patients were studied. During follow-up, chlorthalidone recipients (n = 10 384) experienced the primary outcome at a rate of 3.2 events per 100 person-years of follow-up, and hydrochlorothiazide recipients experienced 3.4 events per 100 person-years of follow-up (adjusted hazard ratio, 0.93 [95% CI, 0.81 to 1.06]). Patients treated with chlorthalidone were more likely to be hospitalized with hypokalemia (adjusted hazard ratio, 3.06 [CI, 2.04 to 4.58]) or hyponatremia (adjusted hazard ratio, 1.68 [CI, 1.24 to 2.28]). In 9 post hoc analyses comparing patients initially prescribed 12.5, 25, or 50 mg of chlorthalidone per day with those prescribed 12.5, 25, or 50 mg of hydrochlorothiazide per day, the former were more likely to be hospitalized with hypokalemia for all 6 comparisons in which a statistically significant association was found. The results of other effectiveness and safety outcomes were also consistent with those of the main analysis. Limitation Unmeasured differences in baseline characteristics or physician treatment approaches or an insufficiently large sample may have limited the ability to detect small differences in the comparative effectiveness of the drugs. Conclusion As typically prescribed, chlorthalidone in older adults was not associated with fewer adverse cardiovascular events or deaths than hydrochlorothiazide. However, it was associated with a greater incidence of electrolyte abnormalities, particularly hypokalemia. Primary funding source Ontario Ministry of Health and Long-Term Care.

Background The novel oral anticoagulants, including dabigatran and rivaroxaban, differ in their degree of renal excretion. Methods We conducted a population-based nested case-control study in patients 66 years and older with chronic kidney disease (CKD) (excluding patients undergoing chronic dialysis) who received an oral anticoagulant between April 2006 and March 2013. We calculated odds ratios for hospitalization with a major hemorrhagic event and receipt of dabigatran, rivaroxaban, or warfarin in the preceding 60 days. We also performed a sensitivity analysis to investigate whether a relationship exists between major hemorrhage and advanced age (age Results We identified 237,409 patients with CKD, 4470 (1.9%) of whom experienced a major hemorrhage. We matched these patients to 14,460 controls. The use of dabigatran or rivaroxaban was not associated with a statistically significant elevated risk of hemorrhage compared with warfarin (adjusted odds ratio [aOR], 1.15; 95% confidence interval [CI], 0.91-1.45 for dabigatran; aOR, 1.22; 95% CI, 0.83-1.79 for rivaroxaban). Our sensitivity analysis found that older age was associated with an increased risk of hemorrhage for patients receiving dabigatran (aOR, 1.41; 95% CI, 1.06-1.88); results were similar but did not reach statistical significance for rivaroxaban (aOR, 1.57; 95% CI, 0.91-2.69). Conclusions Among elderly patients with CKD, exposure to dabigatran or rivaroxaban was not associated with a statistically significant increased risk of major hemorrhagic events compared with exposure to warfarin.

First generation mTOR inhibitors (rapalogs) have modest activity in some tumors. We sought to delineate the likely resistance mechanisms to existing mTOR inhibitors as a guide for next generation therapies. We identified FRB domain and kinase domain mutations as causing acquired-resistance to rapamycin and mTOR kinase inhibitor respectively. Resistance to rapamycin was due to loss of binding of the FKBP12-rapamycin complex to the FRB domain of mTOR mutant protein. Resistance to the mTOR kinase inhibitor was not due to a gatekeeper mutation but rather to an increase in the intrinsic kinase activity of the mTOR kinase domain mutant. These and similar mutations have also been identified in tumors from untreated patients. These findings suggest that these mutations are gain of function mutants but also that tumors with these activating mutations will be intrinsically resistant to second generation mTOR kinase inhibitors. We have designed a new class of mTOR inhibitor, RapaLink-1, that takes advantage of the juxtaposition of two drug binding pockets to create a bivalent interaction. This compound potently inhibits mTOR activation in cells with mTOR wild-type and overcomes resistance to existing first and second generation inhibitors. Moreover, intermittent dosing of RapaLink-1 effectively suppresses mTOR-dependent tumor growth in vivo. Thus, such third generation mTOR inhibitors could be useful for treating tumors with activating mutations of mTOR and for tumors with acquired-resistance to current mTOR inhibitors.[N.R. and K.S. contributed equally to this work.] Citation Format: Vanessa S. Rodrik-Outmezguine, Masanori Okaniwa, Zhan Yao, Chris Novotny, Claire McWhirter, Arpitha Banaji, Helen Won, Wai Wong, Mike Berger, Elisa de Stanchina, Derek G. Barratt, Sabina Cosulich, Teresa Klinowska, Neal Rosen, Kevan M. Shokat. Overcoming mTOR resistance mutations with a new generation mTOR inhibitor. [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 2147.

Conflicting evidence exists regarding the association between antidepressant use and reinfarction among high-risk cardiovascular patients. Recent evidence suggests that clinical benefit associated with antidepressants may be related to serotonergic activity, suggesting that some antidepressants may offer greater advantages than others.We conducted a population-based nested case-control study among patients aged 66 years or older who commenced clopidogrel between April 1, 2002 and December 31, 2009, following hospital discharge for acute myocardial infarction (AMI). Cases were those who were readmitted for AMI, underwent percutaneous coronary intervention (PCI), or died within 90 days of discharge. Three controls were matched to each case on age, PCI, and the date of hospital discharge. We categorized exposure to antidepressants as current or no use within 120 days before the index date, and the serotonergic activity of antidepressants was further categorized as low, medium, and high according to their affinity for the serotonin transporter.Among 24 090 patients who received clopidogrel following AMI, we identified 2494 cases. Of these, 2444 (98%) were successfully matched to 7045 controls. After extensive multivariable adjustment, antidepressant use was not associated with lower risk of the composite outcome (adjusted odds ratio [OR] 1.11 and 95% confidence interval [CI] 0.98-1.27). The absence of association was consistent across the different antidepressant groups categorized by serotonin transporter affinity.In high-risk cardiovascular patients with a history of AMI and treated with clopidogrel, antidepressant use is associated with no additional reduction in risk of reinfarction irrespective of serotonin transporter affinity.

Fibric acid derivatives (fibrates) have been shown to increase serum creatinine level in randomized trials.To assess renal outcomes in elderly adults within 90 days of a new fibrate prescription.Population-based cohort study.Ontario, Canada.Patients aged 66 years or older with a new outpatient prescription for a fibrate or ezetimibe (comparator drug) between January 2004 and December 2008.Hospitalization for an increase in serum creatinine level (primary outcome) and consultation with a nephrologist, receipt of dialysis for severe acute kidney injury, all-cause mortality, and increases in serum creatinine level (secondary outcomes). All outcomes were assessed within 90 days of a new prescription for ezetimibe or a fibrate.Compared with ezetimibe users (n = 61,831), fibrate users (n = 19,072) were more likely to be hospitalized for an increase in serum creatinine level (adjusted odds ratio, 2.4 [95% CI, 1.7 to 3.3]) and were more likely to consult a nephrologist (absolute risk difference, 0.15% [CI, 0.01% to 0.29%]; adjusted odds ratio, 1.3 [CI, 1.0 to 1.6]). There were no differences between groups in the risk for all-cause mortality or receiving dialysis for severe acute kidney injury. In a subpopulation of 1110 patients (fibrates, n = 220; ezetimibe, n = 890), 9.1% of fibrate users and 0.3% of ezetimibe users had an increase in serum creatinine level of 50% or more (absolute difference, 8.8% [CI, 4.5% to 13.1%]; odds ratio, 29.6 [CI, 8.7 to 100.5]). Risks were greater among fibrate users with chronic kidney disease.Because hospitalizations for an increase in serum creatinine level were underestimated, absolute differences may be misleading. Most patients (91%) were prescribed fenofibrate. Serum creatinine levels were measured as part of routine care and were not available for everyone or at predefined times.New fibrate use in elderly adults was associated with an increase in serum creatinine level and a small 90-day absolute increase in hospitalizations and nephrologist consultations. There was no detectable effect on dialysis for severe acute kidney injury or on mortality. The mechanism and clinical significance of the increase in serum creatinine level with fibrates is unclear.Ontario Ministry of Health and Long-Term Care Drug Innovation Fund.

Histiocytic neoplasms are clonal, hematopoietic disorders characterized by an accumulation of abnormal monocyte-derived dendritic cells or macrophages in Langerhans Cell (LCH) and non-Langerhans (non-LCH) histiocytoses, respectively. The discovery of the BRAF V600E mutation in ~50% of patients with LCH and the non-LCH Erdheim-Chester Disease (ECD) provided the first molecular target in these patients and novel insights into the pathogenesis of these disorders. However, recurrent mutations in the majority of the ~50% of BRAF V600E-wild type patients with non-LCH are unknown. Moreover, recurrent mutations outside of the MAP kinase pathway are undefined throughout histiocytic neoplasms. To address these issues, we performed whole exome sequencing (WES) of frozen biopsies from 24 patients with LCH (n=10) or ECD (n=14) paired with peripheral blood mononuclear cells. 13/24 patients also underwent RNA sequencing (RNA-seq). All mutations in activating kinases were validated by droplet-digital PCR, while targeted-capture next-generation sequencing validated all others. Both adult (n=18; n=2 with LCH) and pediatric cases (n=9; n=8 with LCH) were included. Using combined WES/RNA-seq, activating kinase alterations were identified in 100% of patients. In LCH, 60% and 40% had BRAF V600E and MAP2K1 mutations, respectively. In non-LCH 51%, 14%, 14%, and 7% were BRAFV600E, ARAF, MAP2K1, and NRAS mutant (Fig1A). Overall, a mean of 7 non-synonymous mutations per adult patient was identified (range 1-22) compared with 5 mutations per pediatric patient (range 4-9; p =ns). Mutations affecting diverse cellular processes were found to co-exist with kinase mutations including mutations in epigenetic modifiers and the p38/MAPK pathway. In addition to kinase point mutations, RNA-seq identified recurrent, in-frame kinase fusions-a first for these disorders. All identified fusions were validated using FISH and RT-PCR. This includes novel fusions in BRAF (RNF11-BRAF and CLIP2-BRAF), as well as therapeutically important fusions in ALK (2 separate KIF5B-ALK fusions) and NTRK1 (LMNA-NTRK1;Fig1B). Expression of each fusion in Ba/F3 cells conferred cytokine-independent growth. Importantly, the BRAF fusions were found to be sensitive to MEK inhibition but resistant to vemurafenib while the ALK fusions conferred sensitivity to the ALK inhibitors crizotinib or alectinib. We next interrogated a validation cohort of 37 BRAF V600E-wild type, non-LCH, formalin-fixed, paraffin-embedded tissue samples using targeted mutational profiling for MAP2K1, ARAF, NRAS, KRAS, and PIK3CA. This revealed activating mutations in MAP2K1 (32%; n=12), NRAS (16%; n=6), KRAS (11%; n=4), PIK3CA (8%; n=3), and ARAF (3%; n=1). Three of the investigated non-LCH patients with refractory disease and progressive organ dysfunction were treated with targeted therapies based on the discovery of novel kinase alterations described above. Treatment of 2 refractory MAP2K1- mutant, non-LCH patients with MEK inhibitors (trametinib or cobimetinib) resulted in dramatic clinical improvement (Fig1C). Both patients have been maintained on MEK inhibitor single-agent therapy with a sustained clinical response for >100 days. Further evidence of effective targeted inhibition was found in a refractory ECD patient carrying an ARAF S214A mutation. This patient failed to respond to 3 lines of prior therapies and suffered near blindness due to disease infiltration in the retina and optic nerves. Given a recent report of complete response to sorafenib in a lung cancer patient with an ARAF S214C mutation, we initiated sorafenib. Within 12 weeks, there was improvement in the patientÕs eyesight and decreased infiltrative disease, coinciding with >50% decrease in mutant ARAF DNA in plasma cell-free DNA. Whole exome and transcriptome sequencing identified activating kinase mutations or translocations in all patients with the common downstream effect of activating the MAPK pathway. The preliminary, dramatic, clinical efficacy observed with use of MEK and RAF inhibitors in MAP2K1 - and ARAF-mutated, non-LCH patients further supports the central role of targeting the MAPK pathway in these tumors. The discovery of the discussed mutations and fusions in diverse kinases provides critical new insights into the genetic events central to a spectrum of adult and pediatric histiocytic neoplasms. Figure 1. Figure 1. Disclosures Off Label Use: This abstract describes use of MEK inhibitors (both tremetinib and cobimetinib) as well as sorafenib for MEK1 and ARAF mutant histiocytosis. . Stephens:Foundation Medicine, Inc.: Employment, Equity Ownership. Miller:Foundation Medicine, Inc.: Employment, Equity Ownership. Ross:Foundation Medicine Inc.: Employment. Ali:Foundation Medicine Inc.: Employment. Hyman:Chugai Pharma: Consultancy; Biotherapeutics: Consultancy; Atara: Consultancy, Honoraria.

Background: RAF and EGFR inhibitor combinations have shown promising clinical activity in patients with BRAF V600E colorectal cancer, but resistance invariably develops. Methods: To define mechanisms of resistance to RAF/EGFR inhibition, we analyzed pre-treatment and disease progression samples from patients with BRAF mutant colorectal cancer using our custom next-generation sequencing platform, MSK-IMPACT (Integrated Mutation Profiling of Actionable Cancer Targets). Cell line and patient derived xenograft models were generated to investigate the effects of the genetic alterations identified at disease progression. Results: We identified alterations predicted to result in RAF dimerization and re-activation of ERK signaling in seven of eight post-progression tumors. These alterations included an intragenic deletion in BRAF encompassing the RAS binding domain, KRAS and NRAS mutations, and KRAS, NRAS, and BRAF amplifications. Notably, these alterations were rapidly enriched in the presence of drug treatment but selected against in the absence of drug exposure. A novel RAF inhibitor, that equipotently inhibits RAF mutant monomers and dimers, effectively suppressed ERK signaling in the RAF/EGFR resistant colorectal tumors at drug doses that did not inhibit ERK signaling in RAS/RAF wild-type cells. Treatment with this novel RAF inhibitor was able to overcome resistance in cell line and patient derived xenograft models. Conclusions: Our data suggest that alterations that promote RAF dimers, which are resistant to first generation RAF inhibitors, are a unifying mechanism of RAF/EGFR inhibitor resistance in patients with BRAF mutant colorectal cancer. These results support the testing of RAF dimer inhibitors in combination with EGFR inhibitors in patients with BRAF V600E colorectal cancer. Citation Format: Rona Yaeger, Zhan Yao, David M. Hyman, Jaclyn F. Hechtman, Efsevia Vakiani, Andrea Cercek, Jose Baselga, Elisa DeStanchina, Leonard Saltz, Michael F. Berger, David B. Solit, Neal Rosen. RAF kinase dimerization mediates clinical acquired resistance to RAF/EGFR inhibition in BRAF V600E colorectal cancer. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr C174.