Citations

Earlier reports showed that hyperplasia of sympathoadrenal cell precursors during embryogenesis in Nf1-deficient mice is independent of Nf1’s role in down-modulating RAS-MAPK signaling. We demonstrate in zebrafish that nf1 loss leads to aberrant activation of RAS signaling in MYCN-induced neuroblastomas that arise in these precursors, and that the GTPase-activating protein (GAP)-related domain (GRD) is sufficient to suppress the acceleration of neuroblastoma in nf1-deficient fish, but not the hypertrophy of sympathoadrenal cells in nf1 mutant embryos. Thus, even though neuroblastoma is a classical “developmental tumor”, NF1 relies on a very different mechanism to suppress malignant transformation than it does to modulate normal neural crest cell growth. We also show marked synergy in tumor cell killing between MEK inhibitors (trametinib) and retinoids (isotretinoin) in primary nf1a-/- zebrafish neuroblastomas. Thus, our model system has considerable translational potential for investigating new strategies to improve the treatment of very high-risk neuroblastomas with aberrant RAS-MAPK activation.

ObjectiveWhite matter hyperintensities (WMHs) are areas of increased signal on T2‐weighted magnetic resonance imaging (MRI) scans that most commonly reflect small vessel cerebrovascular disease. Increased WMH volume is associated with risk and progression of Alzheimer's disease (AD). These observations are typically interpreted as evidence that vascular abnormalities play an additive, independent role contributing to symptom presentation, but not core features of AD. We examined the severity and distribution of WMH in presymptomatic PSEN1, PSEN2, and APP mutation carriers to determine the extent to which WMH manifest in individuals genetically determined to develop AD.MethodsThe study comprised participants (n = 299; age = 39.03 ± 10.13) from the Dominantly Inherited Alzheimer Network, including 184 (61.5%) with a mutation that results in AD and 115 (38.5%) first‐degree relatives who were noncarrier controls. We calculated the estimated years from expected symptom onset (EYO) by subtracting the affected parent's symptom onset age from the participant's age. Baseline MRI data were analyzed for total and regional WMH. Mixed‐effects piece‐wise linear regression was used to examine WMH differences between carriers and noncarriers with respect to EYO.ResultsMutation carriers had greater total WMH volumes, which appeared to increase approximately 6 years before expected symptom onset. Effects were most prominent for the parietal and occipital lobe, which showed divergent effects as early as 22 years before estimated onset.InterpretationAutosomal‐dominant AD is associated with increased WMH well before expected symptom onset. The findings suggest the possibility that WMHs are a core feature of AD, a potential therapeutic target, and a factor that should be integrated into pathogenic models of the disease. Ann Neurol 2016;79:929–939

AbstractBACKGROUNDFor many years, basic and clinical researchers have taken advantage of the analytical sensitivity and specificity afforded by mass spectrometry in the measurement of proteins. Clinical laboratories are now beginning to deploy these work flows as well. For assays that use proteolysis to generate peptides for protein quantification and characterization, synthetic stable isotope–labeled internal standard peptides are of central importance. No general recommendations are currently available surrounding the use of peptides in protein mass spectrometric assays.CONTENTThe Clinical Proteomic Tumor Analysis Consortium of the National Cancer Institute has collaborated with clinical laboratorians, peptide manufacturers, metrologists, representatives of the pharmaceutical industry, and other professionals to develop a consensus set of recommendations for peptide procurement, characterization, storage, and handling, as well as approaches to the interpretation of the data generated by mass spectrometric protein assays. Additionally, the importance of carefully characterized reference materials—in particular, peptide standards for the improved concordance of amino acid analysis methods across the industry—is highlighted. The alignment of practices around the use of peptides and the transparency of sample preparation protocols should allow for the harmonization of peptide and protein quantification in research and clinical care.

Bendamustine is a multifunctional alkylating agent with single agent activity in myeloma. We designed the current phase 1/2 trial to determine the maximum tolerated doses (MTD) of bendamustine that can be safely combined with lenalidomide and dexamethasone and to assess the safety and efficacy of the combination. Patients with relapsed MM following at least 1 prior therapy, but no more than four lines of prior therapy and with measurable disease were enrolled. Bendamustine 75 mg/m2 given on days 1 and 2, lenalidomide 25 mg given days 1–21 and dexamethasone 40 mg on days 1, 8, 15, and 22, was the recommended Phase 2 dose. Seventy‐one patients were accrued: 21 on Phase 1 and 50 on Phase 2. The median age was 62.3 years; patients had a median of three prior lines of therapy (range 1–4), with over 70% of the patients having received prior lenalidomide, bortezomib, and/or peripheral blood stem cell transplant. Thirty‐four of 70 (49%) patients had a confirmed partial response or better, including 20 patients (29%) with a very good partial response or better. An additional 4 patients had a minor response, translating to an overall 55% clinical benefit rate. Grade 3 or higher toxicity was seen in 96% of patients, with ≥grade 3 hematologic in 94% and nonhematologic in 50%. The median progression free survival was 11.8 months and the median duration of response was 23 months. The combination of bendamustine, lenalidomide, and dexamethasone is very effective in relapsed multiple myeloma with high response rates and durable responses Am. J. Hematol. 90:1106–1110, 2015. © 2015 Wiley Periodicals, Inc.

Abstract Genome-wide association studies (GWAS) of multiple myeloma (MM) in Northern Europeans have identified seven novel risk loci (2p23.3, 3p22.1, 3q26.2, 6p21.33, 7p15.3, 17p11.2, 22q13.1). We performed a multiethnic meta-analysis of these regions in 1,274 MM patients and 1,486 controls of European ancestry (EA) and 1,049 MM patients and 7,080 controls of African ancestry (AA), leveraging the differential linkage-disequilibrium of these populations in order to better localize the putative functional variants. We observed directionally consistent effects for all seven index SNPs in both populations, with four significantly associated (p<0.05) with risk in EAs (3p22.1, 7p15.3, 17p11.2, 22q13.1), and two significantly associated with risk in AAs (7p15.3 and 22q13.1). In a fixed effects meta-analysis of six regions (excluding the HLA region on chromosome 6), variation in five of the regions (2p33.3, 3p22.1, 7p15.3, 17p11.2, 22q13.1) had statistically significant associations with risk (Table 1). In one region, the index variant had the strongest association [rs4487645 at 7p15.3, (OR = 1.30, p = 8.7×10−8)]. Five of the six most significantly associated variants identified in the multiethnic analyses overlapped with biologically relevant features indicating regulatory activity based on CD20+ (B lymphocyte) cells, showing evidence of potential function; those included a missense variant in (17p11.2, rs34562254, Pro251Leu) in TNFRSF13B, which encodes a lymphocyte-specific protein in the tumor necrosis factor receptor family that interacts with the NF-kb pathway. Our study shows that these regions are important in MM risk across ethnicities and further supports the use of multiple ethnic groups in genetic studies to enhance identification of risk variants. Table 1.Most significant associations for each region in the multiethnic meta-analysis.Individuals of European AncestryIndividuals of African AncestryMulitethnic Metar2 with IndexcCHRSNPRAaFreqbORP-valueFreqbORP-valueORP-valueP-het2rs732075G0.591.222.0×10−30.621.122.0×10−21.162.6×10−40.280.09/0.283rs73069394A0.191.243.0×10−30.621.181.5×10−21.201.3×10−50.550.77/0.963rs12637184G0.761.136.0×10−20.921.192.7×10−11.151.0×10−20.640.94/1.007rs4487645C0.671.237.0×10−40.891.485.5×10−51.308.7×10−80.07-d17rs34562254A0.121.452.4×10−50.131.212.2×10−31.312.5×10−60.120.33/0.9022rs139400T0.491.224.0×10−40.531.172.1×10−31.191.2×10−60.630.63/0.96aRisk allelebFrequency of the risk allele in European and African ancestry studiescr2 metrics based on 1000 Genomes Project AFR/EUR populationsdIndex SNP Citation Format: Kristin A. Rand, Chi Song, Eric Dean, Daniel Serie, Karen Curtin, Dennis Hazelett, Amie E. Hwang, Xin Sheng, Alex Stram, David J. Van Den Berg, Carol Ann Huff, Leon Bernal-Mizrachi, Michael H. Tomasson, Sikander Ailawadhi, Anneclaire De Roos, Seema Singhal, Karen Pawlish, Edward Peters, Catherine Bock, David V. Conti, Graham Colditz, Todd Zimmerman, Scott Huntsman, John Graff, African Ancestry Prostate Cancer GWAS Consortium,African Ancestry Breast Cancer GWAS Consortium, Stephen J. Chanock, Michael Lieber, Jayesh Mehta, Eric A. Klein, Nalini Janakiraman, Richard K. Severson, Angela R. Brooks-Wilson, Vincent Rajkumar, Elizabeth E. Brown, Laurence Kolonel, Susan Slager, Brian E. Henderson, Graham G. Giles, John J. Spinelli, Brian Chiu, Kenneth C. Anderson, Jeffrey Zonder, Robert Z. Orlowski, Sagar Lonial, Nicola Camp, Celine Vachon, Elad Ziv, Dan O. Stram, Christopher A. Haiman, Wendy Cozen. Multiple myeloma susceptibility loci examined in African and European ancestry populations. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4629. doi:10.1158/1538-7445.AM2015-4629

Abstract Emerging research on the long-term impact of concussions on athletes has allowed public recognition of the potentially devastating effects of these and other mild head injuries. Mild traumatic brain injury (mTBI) is a multifaceted disease for which management remains a clinical challenge. Recent pre-clinical and clinical data strongly suggest a destructive synergism between brain temperature elevation and mTBI; conversely, brain hypothermia, with its broader, pleiotropic effects, represents the most potent neuro-protectant in laboratory studies to date. Although well-established in selected clinical conditions, a systemic approach to accomplish regional hypothermia has failed to yield an effective treatment strategy in traumatic brain injury (TBI). Furthermore, although systemic hypothermia remains a potentially valid treatment strategy for moderate to severe TBIs, it is neither practical nor safe for mTBIs. Therefore, selective head-neck cooling may represent an ideal strategy to provide therapeutic benefits to the brain. Optimizing brain temperature management using a National Aeronautics and Space Administration (NASA) spacesuit spinoff head-neck cooling technology before and/or after mTBI in contact sports may represent a sensible, practical, and effective method to potentially enhance recover and minimize post-injury deficits. In this paper, we discuss and summarize the anatomical, physiological, preclinical, and clinical data concerning NASA spinoff head-neck cooling technology as a potential treatment for mTBIs, particularly in the context of contact sports.