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Abstract Background. Intracellular one-carbon transfer reactions are essential for nucleotide synthesis and methylation of biologic compounds including DNA. Previous studies have linked genetic variants in one-carbon metabolism genes with risk of developing NHL, but little is known regarding the impact of these variants on disease outcome. We evaluated the hypothesis that inherited genetic variation in genes involved in one-carbon metabolism is associated with overall survival in DLBCL. Methods. We genotyped 30 single nucleotide polymorphisms (SNPs) from 18 candidate one-carbon metabolism genes in 215 DLBCL patients who participated in a population-based case-control study conducted from 1998–2000 using the SEER (Surveillance, Epidemiology and End Results) cancer registries in the Detroit, Iowa, Los Angeles and Seattle. Stage, B-symptoms, first course of therapy, date of last follow-up and vital status through early 2005 were obtained from cancer registry files. Cox proportional hazards analysis was used to estimate hazard ratios (HR) and corresponding 95% confidence intervals for the association between individual SNPs and overall survival, adjusting for age, demographic and clinical factors. We also used parallel modeling strategies to identify the best summary multi-SNP risk score to predict survival. Results. The median age at diagnosis was 57 years (range, 20–74), and 50 (23%) of the patients died during follow-up, with a median follow-up of 57 months (range, 31–78 months) for surviving patients. After adjusting for demographic and clinical variables, SNPs in SHMT1 (rs1979276; HRCT/TT=2.47, 1.31–4.67), BHMT (rs585800; HRAT/TT=2.02, 1.16–3.54), and TCN1 (rs526934; HRTT=1.86, 1.04–3.33) were the strongest and most robust predictors of survival. A summary score of the number of deleterious genotypes (0–3) from these three genes was strongly associated with survival (p=7.9 x 10−5) after accounting for demographic and clinical variables (HR=2.58 per deleterious genotype, 95% CI 1.75–3.80). A risk score combining the three SNPs with clinical and demographic variables (score of 0 to 5) was even more strongly associated with survival (p=1.4 x 10−13); the Kaplan Meier survival curves are shown in the Figure. In a time-dependent ROC analysis, the combined risk score had a concordance index of 0.75 at 5 years of follow-up (95% CI 0.69–0.81). Conclusion: Host genetic variation in the one-carbon metabolism genes SHMT1, BHMT, and TCN1, individually and particularly in combination, was associated with overall DLBCL survival after accounting for clinical and demographic factors, supporting a role for this pathway in disease progression. Future work should evaluate interactions of genes from this pathway with dietary nutrients and therapeutic agents in DLBCL prognosis. Figure Figure

Abstract Background: Pruritus in polycythemia vera (PV) has been associated with a high JAK2V617F allele burden (Tefferi et al. Cancer. 2006;106:631, Vannucchi et al, Leukemia2007, in press). However, there is limited information regarding clinical correlates of pruritus per se in PV. Accordingly, we conducted a large (n=418) retrospective study in PV to accurately assess the prevalence and severity of pruritus as well as its relationship with presenting clinical features, bone marrow JAK2V617F allele burden, and prognosis. Methods: The study cohort consisted of a consecutive group of patients with PV who fulfilled the World Health Organization (WHO) diagnostic criteria and in whom information regarding the presence or absence of pruritus at diagnosis was fully documented. Pruritus was graded as being mild, moderate, or severe based on careful review of patient history. Results: Prevalence and severity of pruritus: A total of 418 patients fulfilled the above stipulated criteria for study inclusion (median age of 60 years; 56% males; median follow-up of 73 months). Of these, 131 (31%) experienced pruritus at time of initial diagnosis: mild in 97 patients (74%), moderate in 22 (17%), and severe in 12 (9%). Most patients with mild pruritus (n=92) received no specific therapy for pruritus whereas all 12 patients with severe pruritus required treatment; all 7 patients who received treatment with paroxetine responded. Pruritus and JAK2V617F allele burden: Quantitative measurement of JAK2V617F was performed in 64 patients using genomic DNA from archived bone marrow obtained at the time of PV diagnosis. Mutational frequency was 97%; median mutant allele burden was 25.4% (range 0.2 - 93.3%). Among the 62 V617F-positive patients, 24 (39%) had pruritus; the proportion of patients in the upper and lower quartile allele burden ranges were 50% and 0% in the presence of pruritus and 18% and 34% in its absence (p=0.002). Clinical correlates of pruritus: Pruritus was more prevalent in non-smokers (35% vs. 19%; p=0.004) and non-diabetics (33% vs. 16%; p=0.04) and was associated with a lower rate of arterial thrombosis at diagnosis (8% vs. 17%; p=0.01) as well as during follow-up (16% vs. 30%; p=0.003). These significant associations remained intact during multivariable analysis. Pruritus did not have an impact on the rate of leukemic or fibrotic transformation. Conclusions: Pruritus in PV is independently associated with a lower risk of arterial thrombosis despite high JAK2V617F allele burden and is also more prevalent in non-smokers. These observations suggest that pruritus might be a surrogate for an underlying platelet pathology with functional relevance.

Background Repetitive hypoxic apneas, similar to what is observed in sleep apnea, result in resetting of the sympathetic baroreflex to higher blood pressures (BP) in humans. This resetting of the baroreflex is associated with increased BP in preclinical models of sleep apnea (chronic intermittent hypoxia, CIH); however, the majority of our understanding comes from men. There are data to suggest female rats exposed to CIH do not develop high BP. With this, we sought to examine potential sex‐related differences in the effect of intermittent hypoxia (IH) on the sympathetic baroreflex. We hypothesized young men would exhibit resetting of the baroreflex to higher BP following IH, with no change in young women. Methods BP and muscle sympathetic nerve activity (MSNA) were assessed in 17 men (30±1 yrs) and 10 women (28±1 yrs) during quiet normoxic rest prior to and following 30‐min of experimental IH [30‐s hypoxic exposures (0.05 F i O 2 ) alternating with 90‐s room air breathing] resulting in 15 hypoxic events (91.7±0.5 % SpO2). Sympathetic baroreflex sensitivity was evaluated using the modified Oxford technique before and after 30‐min of IH. Results Diastolic BP increased in men following IH (71±2 to 74±2 mmHg; p<0.01) with no change in women (75±3 to 75±3 mmHg; p=0.97). Sympathetic baroreflex sensitivity did not change following IH in either group (Men: −1.8±0.2 to −1.9±0.3; Women: −1.6±0.3 to −2.1± 0.5 bursts/100 heart beats/mmHg; Main effect of IH, p=0.14; Interaction of group and IH, p=0.28). Conclusion Acute IH resets the sympathetic baroreflex to higher BP in young men, with no change in young women. Baroreflex sensitivity slopes were unchanged in either group following IH. Our results support sex differences in the effect of IH on sympathetic control of BP and show that young women are protected from the BP‐raising effects of IH. These data enhance our understanding of sex‐specific mechanisms that may contribute to the development of hypertension in sleep apnea. Support or Funding Information NIH HL130339, Mayo Clinic Center for Biomedical Discovery

8043 Background: Mammalian target of rapamycin (mTOR) is a serine-threonine kinase that regulates the production vascular endothelial growth factor (VEGF) and cell growth and proliferation. Inhibitors of mTOR have anti-mitotic and anti-angiogenic effects in various cancers (including melanoma). Everolimus (RAD-001), an orally administered inhibitor of mTOR, is well tolerated at a dose of 30 mg/week. We conducted a phase II study to evaluate the role of RAD-001 in treating patients with metastatic melanoma (MM). Methods: A 2 stage, phase II multi-institutional trial was conducted in patients with MM to assess progression free survival (PFS) rate at 16 weeks was at least 50% against the alternative it was at most 30%. Data about expected baseline PFS were derived from historical controls. Each cycle was 8 weeks in duration. Inclusion criteria: measurable disease, ECOG performance score (PS) of 0–2. Exclusion criteria: presence of intracranial metastases, concurrent use of inducers of cytochrome 3A4 and abnormal hepatic, renal or bone marrow function. Correlative studies included changes pharmacodynamic endpoints to evaluate effect of therapy on signaling pathways. Results: 24 patients with MM were enrolled. Median age was 56 years (33–79), 21 (88%) had at 2 or more sites of metastatic disease. Most (75%) had stage M1c, with 13% each having 1a and 1b disease. PS was 0, 1 and 2 in 58, 38% and 4%, resp. All but 9 had received previous therapy for MM. Planned interim analysis was done after 20 patients were enrolled. Of these, 7 (i.e., 35%) were PF at 16 weeks, which exceeded the decision rule for restarting accrual. No patient had an objective response; all 7 had stable disease. There were no grade 3 toxicities. Grade 2 toxic events (at least possibly related to therapy) were: fatigue (17%), diarrhea (8%) and anemia (8%). Patients had a clinically relevant benefit, with the median PFS for all 24 patients of 3 months. Median overall survival was not reached. Three patients continue on therapy. RAD-001 treatment resulted in changes in serum VEGF levels. Conclusion: Interim analysis after enrollment of 20 patients suggests that RAD-001 is well tolerated and has sufficient anti-tumor activity in MM to warrant the opening of enrollment to the second stage of this trial. Further accrual is planned. No significant financial relationships to disclose.

8041 Background: ABT-510 is a synthetic peptide analog of thrombospondin-1 demonstrating inhibition of VEGF/bFGF mediated human endothelial cell migration, proliferation, tube formation, cornea-neovascularization as well as inhibition of tumor growth in vivo (B16F10 melanoma). Having been found to be safe in phase I testing, ABT-510 has entered phase II trials. Presented are the results of a phase II study using ABT-510 for the treatment of stage IV melanoma. Methods: A two stage phase II clinical trial was conducted to assess the anti-tumor activity, safety profile and pharmacodynamics of ABT510 in patients with stage IV melanoma. Patients self-administered 100mg of ABT-510 subcutaneously twice/day. Therapy was continued in the absence of excessive toxicity or tumor progression. Primary endpoint was 18 week progression free survival rate. Enrolled were patients at least 18 years of age with measurable (RECIST) metastatic melanoma, ECOG performance status of 0–2 and normal pre-registration blood tests. Exclusion criteria included: cancer therapy less than 4 weeks prior to registration; failure to recover from prior therapy; brain metastases; significant recent bleeding; uncontrolled hypertension; and ongoing anti-coagulation. Pregnant or nursing women were not eligible. Results: Twenty-one patients (67% male) were enrolled with a median age of 55 years. Most patients had M1c disease (80%) and 62% had prior chemotherapy for stage IV melanoma. None of the patients were ineligible/canceled participation. After the first stage of the trial was complete, only 3 of the first 20 patients enrolled were progression-free at 18 weeks. Having not met the minimal clinical efficacy requirement (at least 7 of the first 20 patients progression-free at 18 weeks) the trial was closed to further accrual. Correlative laboratory studies suggested decreases in some of the measured parameters of angiogenesis (VEGFC, circulating endothelial cells) with no impact on immune homeostasis. Conclusions: Single agent ABT-510 therapy administered at 100mg twice/day to patients with previously treated metastatic melanoma did not demonstrate significant clinical efficacy. However, changes in measured parameters of angiogenesis suggest possible clinical efficacy with higher dosing or in combination with cytotoxic therapy. [Table: see text]

INTRODUCTION Patients with peripheral artery disease (PAD) are at a heightened risk of cardiovascular events and have markedly reduced vascular function and exercise tolerance. Heat therapy (HT) has emerged as a practical treatment to improve cardiovascular health in young individuals as well in patients with overt cardiovascular disease. We recently reported that a single 90 min session of HT applied to the legs of patients with PAD using water‐circulating trousers increases popliteal artery blood flow and reduces blood pressure and the circulating levels of the potent endogenous vasoconstrictor endothelin‐1 (ET‐1). The objective of the present study was to test the hypothesis that the repeated exposure to leg HT would lower blood pressure and ET‐1 levels and improve walking performance and conduit artery and cutaneous vascular function in patients with symptomatic PAD. METHODS Thirty‐two patients with symptomatic PAD (Age: 68± 8 years; Ankle‐brachial index: 0.67 ± 0.1) were assigned using a balanced randomized design to undergo 90 min of HT (48°C) or a thermoneutral treatment (33°C) 3 times per week for 6 consecutive weeks. The following outcomes were assessed at baseline and 3 and 6 weeks after the intervention: 1) resting ankle‐brachial index, 2) post‐occlusive reactive hyperemia in the popliteal artery (phase contrast magnetic resonance imaging), 3) leg cutaneous thermal hyperemia (laser Doppler flowmetry), 4) resting blood pressure every 5 min for 70 min, 5) 6‐min walk distance and 6) serum levels of ET‐1 and total nitrate (NOx). RESULTS Participants completed 17.7 ± 0.6 treatment sessions, resulting in a compliance rate of 98.7%. In the group exposed to HT, systolic blood pressure (SBP) decreased from baseline by ~3 mmHg at 6 weeks, while in the control group SBP increased by ~1 mmHg. A significant group by time interaction was observed for the changes in SBP from baseline to 6 weeks ( p=0.0049) with significant group differences at 20 min (Change in SBP: Control: 6.27 ± 15.5 vs. HT: −7.60 ± 13.6 mmHg, p=0.015 ) and 60 min (Change in SBP: Control: 4.13 ± 15.1 vs. HT: −7.33 ± 13.7 mmHg, p=0.0386 ). Similarly, serum ET‐1 levels decreased by ~15% from baseline to week 6 following exposure to HT, while a ~6% increase in this parameter occurred in the control group (Change in ET‐1: Control: 0.16 ± 0.6 vs. HT: −0.30 ± 0.4 pg/mL, p=0.035 – one outlier removed). Resting ABI, diastolic BP, 6MWT distance, hyperemic peak flow and cutaneous thermal hyperemia were not different between groups. CONCLUSION Exposure to repeated HT reduces systolic blood pressure and ET‐1 levels in patients with symptomatic PAD. These findings indicate that HT may be a practical and accessible nonpharmacological tool to reduce cardiovascular risk in PAD patients. Support or Funding Information American Heart Association Scientist Development grant (16SDG27600003).

Patients admitted to the cardiac intensive care unit (CICU) are often in shock and require hemodynamic support. Identifying and addressing the pathophysiology mechanisms operating in an individual patient is crucial to achieving a successful outcome, while initiating circulatory support therapy to restore adequate tissue perfusion. Vasopressors and inotropes are the cornerstone of supportive medical therapy for shock, in addition to fluid resuscitation when indicated. Timely initiation of optimal vasopressor and inotrope therapy is essential for patients with shock, with the ultimate goals of restoring effective tissue perfusion in order to normalize cellular metabolism. Use of vasoactive agents for hemodynamic support of patients with shock should take both arterial pressure and tissue perfusion into account when choosing therapeutic interventions. For most patients with shock, including cardiogenic or septic shock, norepinephrine (NE) is an appropriate choice as a first-line vasopressor titrated to achieve an adequate arterial pressure due to a lower risk of adverse events than other catecholamine vasopressors. If tissue and organ perfusion remain inadequate, an inotrope such as dobutamine may be added to increase cardiac output to a sufficient level that meets tissue demand. Low doses of epinephrine or dopamine may be used for inotropic support, but high doses of these drugs carry an excessive risk of adverse events when used for vasopressor support and should be avoided. When NE alone is inadequate to achieve an adequate arterial pressure, addition of a noncatecholamine vasopressor such as vasopressin or angiotensin-II is reasonable, in addition to rescue therapies that may improve vasopressor responsiveness. In this review, we discuss the pharmacology and evidence-based use of vasopressor and inotrope drugs in critically ill patients, with a focus on the CICU population.

Abstract Wiskott-Aldrich syndrome (WAS) is an X-linked disease caused by mutations in the WAS gene, leading to thrombocytopenia, eczema, recurrent infections, autoimmune disease, and malignancy. Hematopoietic cell transplantation (HCT) is the primary curative approach, with the goal of correcting the underlying immunodeficiency and thrombocytopenia. HCT outcomes have improved over time, particularly for patients with HLA-matched sibling and unrelated donors. We report the outcomes of 129 patients with WAS who underwent HCT at 29 Primary Immune Deficiency Treatment Consortium centers from 2005 through 2015. Median age at HCT was 1.2 years. Most patients (65%) received myeloablative busulfan-based conditioning. With a median follow-up of 4.5 years, the 5-year overall survival (OS) was 91%. Superior 5-year OS was observed in patients &lt;5 vs ≥5 years of age at the time of HCT (94% vs 66%; overall P = .0008). OS was excellent regardless of donor type, even in cord blood recipients (90%). Conditioning intensity did not affect OS, but was associated with donor T-cell and myeloid engraftment after HCT. Specifically, patients who received fludarabine/melphalan-based reduced-intensity regimens were more likely to have donor myeloid chimerism &lt;50% early after HCT. In addition, higher platelet counts were observed among recipients who achieved full (&gt;95%) vs low-level (5%-49%) donor myeloid engraftment. In summary, HCT outcomes for WAS have improved since 2005, compared with prior reports. HCT at a younger age continues to be associated with superior outcomes supporting the recommendation for early HCT. High-level donor myeloid engraftment is important for platelet reconstitution after either myeloablative or busulfan-containing reduced intensity conditioning. (This trial was registered at www.clinicaltrials.gov as #NCT02064933.)

We examined the effect of acute intermittent hypoxia (IH) on sympathetic neural firing patterns and the role of the carotid chemoreceptors. We hypothesized exposure to acute IH would increase muscle sympathetic nerve activity (MSNA) via an increase in action potential (AP) discharge rates and within-burst firing. We further hypothesized any change in discharge patterns would be attenuated during acute chemoreceptor deactivation (hyperoxia). MSNA (microneurography) was assessed in 17 healthy adults (11 male/6 female; 31 ± 1 yr) during normoxic rest before and after 30 min of experimental IH. Prior to and following IH, participants were exposed to 2 min of 100% oxygen (hyperoxia). AP patterns were studied from the filtered raw MSNA signal using wavelet-based methodology. Compared with baseline, multiunit MSNA burst incidence ( P < 0.01), AP incidence ( P = 0.01), and AP content per burst ( P = 0.01) were increased following IH. There was an increase in the probability of a particular AP cluster firing once ( P < 0.01) and more than once ( P = 0.03) per burst following IH. There was no effect of hyperoxia on multiunit MSNA at baseline or following IH ( P > 0.05); however, hyperoxia following IH attenuated the probability of particular AP clusters firing more than once per burst ( P < 0.01). Acute IH increases MSNA by increasing AP discharge rates and within-burst firing. A portion of the increase in within-burst firing following IH can be attributed to the carotid chemoreceptors. These data advance the mechanistic understanding of sympathetic activation following acute IH in humans.