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We report on whole-exome sequencing (WES) of 213 melanomas. Our analysis established NF1, encoding a negative regulator of RAS, as the third most frequently mutated gene in melanoma, after BRAF and NRAS. Inactivating NF1 mutations were present in 46% of melanomas expressing wild-type BRAF and RAS, occurred in older patients and showed a distinct pattern of co-mutation with other RASopathy genes, particularly RASA2. Functional studies showed that NF1 suppression led to increased RAS activation in most, but not all, melanoma cases. In addition, loss of NF1 did not predict sensitivity to MEK or ERK inhibitors. The rebound pathway, as seen by the induction of phosphorylated MEK, occurred in cells both sensitive and resistant to the studied drugs. We conclude that NF1 is a key tumor suppressor lost in melanomas, and that concurrent RASopathy gene mutations may enhance its role in melanomagenesis. [ABSTRACT FROM AUTHOR]

Learning and memory require orchestrated regulation of both structural and functional synaptic plasticity in the hippocampus. While a neuropeptide alpha-melanocyte-stimulating hormone, a-MSH, has been implicated in memory acquisition and retention, the functional role of its cognate receptor, melanocortin-4 receptor (MC4R), in hippocampal-dependent synaptic plasticity has not been explored. In this study, we report that activation of MC4R enhances synaptic plasticity through the regulation of dendritic spine morphology and abundance of AMPA receptors. We show that activation of postsynaptic MC4R increases the number of mature dendritic spines and enhances surface expression of AMPA receptor subunit GluAl, resulting in synaptic accumulation of GluAl-containing AMPA receptors. Moreover, MC4R stimulates surface GluAl trafficking through phosphorylation of GluAl at Ser845 in a Gas-cAMP/PKA-dependent manner. Blockade of protein kinase A (PKA) signaling abolishes the MC4R-mediated enhancement of neurotransmission and hippocampal long-term potentiation. Importantly, in vivo application of MC4R agonists increases LTP in the mouse hippocampal CAI region. These findings reveal that MC4R in the hippocampus plays a critical role in the regulation of structural and functional plasticity. [ABSTRACT FROM AUTHOR]

BRAFV600E/K is a frequent mutationally active tumor-specific kinase in melanomas that is currently targeted for therapy by the specific inhibitor PLX4032. Our studies with melanoma tumor cells that are BRAFV600E/K and BRAFWT showed that, paradoxically, while PLX4032 inhibited ERK1/2 in the highly sensitive BRAFV600E/K, it activated the pathway in the resistant BRAFWT cells, via RAF1 activation, regardless of the status of mutations in NRAS or PTEN. The persistently active ERK1/2 triggered downstream effectors in BRAFWT melanoma cells and induced changes in the expression of a wide-spectrum of genes associated with cell cycle control. Furthermore, PLX4032 increased the rate of proliferation of growth factor-dependent NRAS Q61L mutant primary melanoma cells, reduced cell adherence and increased mobility of cells from advanced lesions. The results suggest that the drug can confer an advantage to BRAFWT primary and metastatic tumor cells in vivo and provide markers for monitoring clinical responses. [ABSTRACT FROM AUTHOR]

Background In 2003 the National Institute of Clinical Excellence published guidelines recommending the use of brain natriuretic peptipe (BNP) and the electrocardiogram (ECG) as part of the diagnostic work up of individuals with heart failure. However, the guideline did not address whether one test was superior to the other or whether performing both tests was superior to performing single tests. Aim To investigate the relative test accuracy of the ECG, BNP, N terminal-pro brain natriuretic peptide (NT-proBNP) and combinations of two or more tests in the diagnosis of left ventricular systolic dysfunction (LVSD) in the primary care setting. Design of study Cohort studies making within-subject comparisons of intervention diagnostic test(s) with reference standard results. Method Standard systematic review methodology was followed. Results Thirty-two primary studies met the review inclusion criteria. Studies were of variable quality and highly clinically heterogeneous, therefore restricting the use of meta-analysis. Within these limitations BNP, NT-proBNP and the ECG all had similar test sensitivity (>80% in the majority of studies). Specificity of the three tests was not as good. Three studies directly comparing BNP and the ECG found no difference in sensitivity and limited support for improved specificity of BNP. Two studies found no difference in sensitivity and limited evidence for an improvement in specificity for the combination of the ECG and BNP compared to single tests. Conclusion On the basis of existing evidence, the ECG, BNP and NT-proBNP are useful in excluding a diagnosis of LVSD (good sensitivity). However, use of abnormal test results to select individuals for echocardiography may overwhelm services. There is currently no evidence to justify the use of one test over another or the use of tests in combination. The additional cost of BNP is not self-evidently justified by improved test accuracy. Further research is needed to directly compare the diagnostic performance of these tests in homogeneous, representative primary care populations. [ABSTRACT FROM AUTHOR]

Activating mutations in BRAF kinase are common in melanomas. Clinical trials with PLX4032, the mutant-BRAF inhibitor, show promising preliminary results in patients selected for the presence of V600E mutation. However, activating V600K mutation is the other most common mutation, yet patients with this variant are currently excluded from the PLX4032 trials. Here we present evidence that a patient bearing the BRAF V600K mutation responded remarkably to PLX4032, suggesting that clinical trials should include all patients with activating BRAF V600E/K mutations. [ABSTRACT FROM AUTHOR]

Historically, the OPTN liver allocation policies have favored candidates listed with MELD exception scores, and the use of exceptions has increased each year since the inception of the MELD era. The implementation of Share 35 and other recent changes in OPTN liver allocation policies have reduced the preference for MELD exception candidates to some extent, but the nature and degree of the impact appears to vary widely from one region to another. This report emphasizes the geographic inequities and regional variations in transplant practices, with a focus on liver transplant candidates with hepatocellular carcinoma exceptions, and highlights the need for strategies to promote equitable organ distribution across geographical regions and patient conditions., (Copyright© 2016 by the Terasaki Foundation Laboratory.)

As of September 19, 2014, 2441 cases of intestinal transplantation have been performed in 46 centers (2400 deceased, 41 living). Eight centers did more than 100 transplants. Annual case numbers peaked in 2007 (N = 198) and steadily decreased to 109 cases in 2013. Short gut syndrome (68%) and functional bowel problems (15%) are two major indications for intestinal transplantation. The 3 major types of transplants involving the intestine include: isolated intestine transplant (I); simultaneous intestine, liver, and pancreas transplant (I+L+P); and, combined intestine and liver (I+L) transplant. Graft survival has significantly improved in recent years, mainly due to improved first year graft survival. The 1-, 5-, and 10-year graft survivals were: 74%, 42%,and 26%, respectively (I); 70%, 50%, and 40%, respectively (I+L+P); and 61%, 46%, and 40%, respectively (I+L). The longest graft survivals for I, l+L+P, and l+L were 19 years, 16 years, and 23 years, respectively. Steroids, Thymoglobulin, and rituximab are 3 major induction agents used in recent years. Prograf, steroids, and Cellcept are 3 major maintenance agents. Induction recipients (68% of all patients) had a significantly lower acute rejection rate than nonrecipients before discharge (60% versus 75%, p < 0.001). Most of the patients received 2 (53%) or 3 (25%) maintenance immunosuppressants. Acute rejection episodes were usually treated with one (60%) or two agents (27%). Steroids were most commonly used (50-60%). OKT3 has been replaced with antithymocyte globulin (since 1999) and rituximab (since 2006). During 1990-2000, 94% (N = 445) of patients received ABO identical intestinal transplants, while 6% (N = 29) received ABO compatible transplants. ABO identical transplant recipients had a significantly higher 5-year graft survival rate than ABO compatible recipients (39% versus 21%, p < 0.0001). In recent years (2001- 2012), more patients received ABO compatible (N = 188, 11%) than in the early decade (p < 0.01). 5-year graft survival rates of ABO compatible transplants were lower than those of ABO identical transplants. However, the difference did not reach statistical significance (46% versus 49%, p = 0.07). The effect of ABO compatibility on graft outcome was further confirmed by Cox Analysis. ABO incompatible transplants are still rarely performed (N = 4) in intestine. In conclusion, annual case numbers of intestinal transplants have been decreasing, regardless of improved graft survival. ABO compatible intestinal transplants previously had a significantly lower graft survival rate than ABO identical transplants. However, the graft survival difference became less significant in recent years, possibly due to, or at least partly due to the use of new immunosuppressive agents.

Intestinal transplantation is a viable treatment strategy for patients with irreversible intestinal failure for whom parenteral nutrition is no longer an option. Although improvements have been made in short-term post-transplant survival outcomes, long-term allograft loss, mainly to acute or chronic rejection, remains a major obstacle to successful transplantation. In all types of solid organ transplants, there is increasing evidence that antibodies directed against human leukocyte antigens, and in particular donor-specific antibodies (DSA), contribute to acute and chronic rejection as well as allograft loss. In this single-center review of intestinal transplant recipients, we report that the presence of pretransplant circulating DSA and the de novo induction of DSA posttransplant are both associated with increased risks of allograft loss. Although the cumulative incidence of acute rejection was not significantly affected by the presence of DSA, the power of this single-center study may be limited. Prospective, multicenter studies are needed to further elucidate the role of DSA in intestinal transplant recipients. In the published literature, there is a clear link between the presence of pre-formed DSA and early injury to the mucosal vasculature of the allograft. Two groups have reported an association between pretransplant DSA and the frequency of acute rejection episodes and subsequent graft loss. Similarly, studies investigating the effects of de novo DSA have demonstrated a relationship between the presence of post-transplant circulating antibodies and the occurrence of acute rejection and the risk of allograft failure. The use of a liver-containing graft appears to facilitate the clearance of pre-formed antibodies and prevents the de novo induction of post-transplant antibodies. The most recent report stated that the de novo induction of DSA is concurrently accompanied by signs or rejection, such that the detection of circulating antibodies may signify impending graft injury, and supports the potential utility of DSA as a non-invasive biomarker for rejection in intestinal transplantation.

Advances in immunosuppression (IS) agents and strategies have resulted in reduced rejection rates and improved survival outcomes after liver transplantation. The use of induction and maintenance IS agents is both associated with reductions in acute rejection (AR) risk within the first 6 to 12 months posttransplant and with superior failure-free survival. With the lowered incidence of allograft losses attributable to rejection, the long-term sequelae of IS have become the major therapeutic challenge. The long-term use of calcineurin inhibitors and corticosteroids in maintenance immunotherapy regimens has been implicated in the development of renal dysfunction, infections, metabolic derangements, de novo and recurrent malignancies, and the propagation of hepatitis C virus reinfection. Our analysis of the United Network for Organ Sharing registry shows the use of induction and maintenance therapy is each associated with reductions in AR risk, thereby improving post-transplant survival. The administration of intensive induction regimens appears to be safe and exhibits an additive beneficial effect. Therefore, the use of intensive induction regimens may be warranted to allow for reductions in long-term maintenance IS to minimize drug toxicities while preserving graft outcomes.

Learning and memory require orchestrated regulation of both structural and functional synaptic plasticity in the hippocampus. While a neuropeptide alpha-melanocyte-stimulating hormone, α-MSH, has been implicated in memory acquisition and retention, the functional role of its cognate receptor, melanocortin-4 receptor (MC4R), in hippocampal-dependent synaptic plasticity has not been explored. In this study, we report that activation of MC4R enhances synaptic plasticity through the regulation of dendritic spine morphology and abundance of AMPA receptors. We show that activation of postsynaptic MC4R increases the number of mature dendritic spines and enhances surface expression of AMPA receptor subunit GluA1, resulting in synaptic accumulation of GluA1-containing AMPA receptors. Moreover, MC4R stimulates surface GluA1 trafficking through phosphorylation of GluA1 at Ser845 in a Gα(s)-cAMP/PKA-dependent manner. Blockade of protein kinase A (PKA) signaling abolishes the MC4R-mediated enhancement of neurotransmission and hippocampal long-term potentiation. Importantly, in vivo application of MC4R agonists increases LTP in the mouse hippocampal CA1 region. These findings reveal that MC4R in the hippocampus plays a critical role in the regulation of structural and functional plasticity.

The heterogeneity of tumor samples is a major challenge in the analysis of high-throughput profiling of tumor biopsies and cell lines. The measured aggregate signals of multigenerational progenies often represent an average of several tumor subclones with varying genomic aberrations and different gene expression levels. The goal of the present study was to integrate copy number analyses from SNP-arrays and karyotyping, gene expression profiling, and pathway analyses to detect heterogeneity, identify driver mutations, and explore possible mechanisms of tumor evolution. We showed the heterogeneity of the studied samples, characterized the global copy number alteration profiles, and identified genes whose copy number status and expression levels were aberrant. In particular, we identified a recurrent association between two BRAF(V600E) and BRAF(V600K) mutations and changes in DKK1 gene expression levels, which might indicate an association between the BRAF and WNT pathways. These findings show that the integrated approaches used in the present study can robustly address the challenging issue of tumor heterogeneity in high-throughput profiling.

Decitabine, an epigenetic modifier that reactivates genes otherwise suppressed by DNA promoter methylation, is effective for some, but not all cancer patients, especially those with solid tumors. It is commonly recognized that to overcome resistance and improve outcome, treatment should be guided by tumor biology, which includes genotype, epigenotype, and gene expression profile. We therefore took an integrative approach to better understand melanoma cell response to clinically relevant dose of decitabine and identify complementary targets for combined therapy. We employed eight different melanoma cell strains, determined their growth, apoptotic and DNA damage responses to increasing doses of decitabine, and chose a low, clinically relevant drug dose to perform whole-genome differential gene expression, bioinformatic analysis, and protein validation studies. The data ruled out the DNA damage response, demonstrated the involvement of p21(Cip1) in a p53-independent manner, identified the TGFbeta pathway genes CLU and TGFBI as markers of sensitivity to decitabine and revealed an effect on histone modification as part of decitabine-induced gene expression. Mutation analysis and knockdown by siRNA implicated activated beta-catenin/MITF, but not BRAF, NRAS or PTEN mutations as a source for resistance. The importance of protein stability predicted from the results was validated by the synergistic effect of Bortezomib, a proteasome inhibitor, in enhancing the growth arrest of decitabine in otherwise resistant melanoma cells. Our integrative analysis show that improved therapy can be achieved by comprehensive analysis of cancer cells, identified biomarkers for patient's selection and monitoring response, as well as targets for improved combination therapy.

The SRS-22 questionnaire is specifically designed for the assessment of quality of life in spinal deformity patients. This study is the first to use it to assess the quality of life of adolescent idiopathic scoliosis patients under brace treatment and compares the results with an observational group matched by age and curve magnitude. Forty-six patients were enrolled into each group. Overall, it was found that patients under observation had a significantly better quality of life than braced patients. Specifically, the domains for function/activity and self-image were most affected. This effect was most apparent in those with a curve magnitude of under 20 degrees . The scores did not improve significantly with the duration of brace wear, suggesting little adaptation. This study has implications for treatment, and more attention will need to be given to those with mild but progressive curves to help improve patients' understanding of their treatment and hence their compliance and satisfaction.

Constitutive cell surface receptor kinase signaling and persistent phosphorylation/inactivation of the retinoblastoma (pRb) family of proteins (pRb, p107 and p130, known as pocket proteins) have been implicated in conferring uncontrolled growth to melanoma cells. However, the signals linking receptor kinase activity to neutralization of pocket proteins have not yet been fully elucidated. We therefore used specific chemical inhibitors to examine pRb regulation in melanoma cells. The most efficient agent, AG1024, known as an inhibitor of insulin-like growth factor 1 receptor and insulin receptor, arrested melanoma cell growth in vitro at nanomolar concentrations within 24 h of application. AG1024 inhibited the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway and restored pRb tumor suppressive function. The latter was observed by the reduction in the phosphorylated forms of pRb, p107 and p130, and the formation of growth suppressive DNA binding complexes consisting of pRb and E2F1 or E2F3. The loss of phosphorylated forms of pRb at early time points after AG1024 application was not associated with suppression of cyclin-dependent kinases 2 and 4 activity but rather with proteasomal and nonproteasomal degradation. Thus, inhibition of melanoma cell proliferation by AG1024 is mediated by inhibition of mitogen-activated protein kinase/extracellular signal-regulated kinase 2 signaling and activation of pRb by a mechanism involving protein degradation.