Citations

Abstract Dynamic susceptibility contrast (DSC) MRI measures of brain tumor cerebral blood volume (CBV) are able to predict grade, overall survival and response to treatment. Wide-spread acceptance of DSC-MRI has been challenged by the need to balance contrast agent dose and CBV accuracy. The goal of this study was to identify and validate single-dose, BTIP compliant, DSC-MRI protocols. Using a validated, patient-based DRO, we evaluated CBV accuracy across a range of acquisition parameters (field strength, TR, TE, flip angle, multi-echo acquisitions, dosing protocols) and post-processing steps. To validate the optimal protocols, we next collected DSC-MRI data following ASFNR’s recommended “double – dose” approach, where a single-dose preload (to minimize T1 effects) is given prior to a second bolus injection (for DSC-MRI data acquisition). The single-dose DSC-MRI data was collected during the preload bolus injection. Consistency of the derived CBV data, visual agreement and data characteristics (e.g. CNR) was statistically evaluated. When using a single-dose and routine single-echo pulse sequence, the DRO analysis found that a low flip angle (LFA = 30o) and 30ms TE provided the highest CBV accuracy (concordance correlation coefficient (CCC) = 0.92) and precision (coefficient of variation (CV) = 8.2%)). For comparison, the maximum accuracy found with the DRO utilizes a double-dose injection protocol and yielded a CCC of 0.98 and CV of 6.8%. Single-dose, multi-echo acquisitions provided higher accuracy than the LFA data and matched that found with the double-dose approach. In patients (data collection ongoing), the agreement between single-dose LFA (n > 40) or multi-echo (n > 40) based CBV values and the reference double-dose approach was very high (CCC > 0.94) and were statistically equivalent. Optimized single-dose DSC-MRI protocols provide highly accurate CBV data, use lower doses of contrast agent, and simplify scan procedures, indicating their potential for robust use in clinical practice and trials.

Transradial access (TRA) is favored over transfemoral access for performing coronary angiography and percutaneous coronary intervention due to the reduced risk for vascular and bleeding complications and the documented survival benefit in ST-segment–elevation myocardial infarction patients who undergo primary percutaneous coronary intervention. TRA complications can be categorized as intra- or postprocedural and further categorized as related to bleeding or nonbleeding issues. Major intra- and postprocedural complications such as radial artery perforation and compartment syndrome are rare following TRA. Their occurrence, however, can be associated with morbid consequences, including requirement for surgical intervention if not identified and treated promptly. Nonbleeding complications such as radial artery spasm and radial artery occlusion are typically less morbid but occur much more frequently. Strategies to prevent TRA complications are essential and include the use of contemporary access techniques that limit arterial injury. This document summarizes contemporary techniques to prevent, identify, and manage TRA complications.

Abstract Prompted by the activity of lenalidomide (Revlimid®) in pts with chronic idiopathic myelofibrosis (CIMF), we sought to evaluate the safety and efficacy of the combination of lenalidomide and prednisone in a phase II study for pts with CIMF. The rationale for this combination is that the anti-angiogenic and anti-TNFa effects of lenalidomide may be potentiated by the effects of prednisone to reduce marrow fibrosis and improve hematopoiesis in CIMF. Initial therapy consisted of lenalidomide 10 mg/d (dose level [DL] 0) on days 1–21 of a 28–day cycle for 6 cycles, in combination with prednisone 30 mg/d orally during cycle 1, 15 mg/d orally during cycle 2, and 15 mg/d every other day during cycle 3. The lenalidomide dose could be reduced to 5 mg/d (DL -1) or to 5 mg/d every other day (DL -2), or increased to 15 mg/d (DL +1) or 20 mg/d (DL +2) depending upon toxicity or lack of response, respectively. A total of 40 pts (23 male, 17 female) have been enrolled. The median age was 62 years (range, 41–86), time from CIMF diagnosis to the study treatment 10 months (range, 0–269), WBC count 87x109/L (range, 1.1–89), hemoglobin 9.8 g/dL (range, 7.8–17.3), platelets 137x109/L (range, 8–1183). Pts had received a median of 1 prior therapy (range 0–4): hydroxyurea (HU; n=14), anagrelide (AG; n=4), azacitidine (n=6), steroids (n=5), thalidomide (n=4), and interferon (n=3). Ten (25%) pts had not received any prior therapy. JAK2 V617F mutation was detected in 18 (50%) of 36 tested pts and 20 (50%) of 40 had abnormal cytogenetics. A total of 260 cycles have been administered. All 40 pts are evaluable for response and toxicity. Responses have been observed in 12 (30%) pts, including complete response (CR) in 2 (normal blood counts and <5% bone marrow blasts, off HU, AG, growth factors, and no transfusions); partial response (PR) in 7 (at least 2 of the following: Hb increase by ≥2 g/dL, 50% increase in platelets, decrease of bone marrow blasts or organomegaly by ≥50%, normalization of WBC count without blasts, or reduction in bone marrow fibrosis; off HU, AG, growth factors, and transfusion independence); and hematologic improvement (HI) in 3 (at least 2 of the following: decrease by ≥25% of pretreatment leukocytosis, splenomegaly, or marrow blasts, or increase of Hb by ≥1g/dl without growth factor or transfusion support or platelets by ≥25%; off HU, AG, growth factors). Median time to response was 12 weeks (range, 2–32). Responses have been sustained for a median of 15 wks (range, 5–36) and are ongoing in all 12 responders. Overall, 21 (53%) pts experienced grade 3–4 toxicity, being the most frequent neutropenia, anemia, musculoskeletal pain, and fatigue. Twenty-four (60%) pts have required dose reduction to DL -1, of which 5 (12.5%) further reduced to DL -2. One (2.5%) pt dose-escalated to DL +1, while 15 (25%) remained at DL 0. Twenty-one (53%) pts discontinued lenalidomide due to: lack of response (n=8), pt’s decision (n=7), grade 3–4 toxicity (n=5), and poor compliance (n=1). No deaths or transformation to acute myeloid leukemia occurred. In summary, the combination of lenalidomide and prednisone is an active and generally well-tolerated regimen for pts with CIMF. Longer follow-up is warranted to evaluate the durability of ongoing responses. Updated results will be presented at the meeting.

Abstract Background: Alzheimer’s disease (AD) is an epidemic with tremendous public health impacts because there are currently no disease-modifying therapeutics. Randomized controlled trials (RCTs) for prevention of AD dementia often use clinical endpoints that take years to manifest (e.g., cognition) or surrogate endpoints that are costly or invasive (e.g., magnetic resonance imaging [MRI]). Blood biomarkers represent a clinically applicable alternative surrogate endpoint for RCTs that would be both cost-effective and minimally invasive, but little is known about their value as surrogate endpoints for treatment responses in the prevention of AD dementia. Methods: The objective of this study is to investigate blood neuropathological, neurodegenerative, and neurotrophic biomarkers as surrogate endpoints for treatment responses to 3 interventions in older adults with amnestic mild cognitive impairment (aMCI, a prodromal stage of AD): aerobic exercise; cognitive training; and combined aerobic exercise and cognitive training (ACT). We chose these three sets of biomarkers for their unique mechanistic associations with AD pathology, neurodegeneration and neurogenesis. This study is built on the ACT Trial (1R01AG055469), a single-blinded, multi-site, 2×2 factorial Phase II RCT that examines the synergistic effects of a 6-month ACT intervention on cognition and MRI biomarkers (AD-signature cortical thickness and hippocampal volume) (n=128). In this ACT Trial Blood Biomarkers Study, we will enroll 120 ACT Trial aMCI participants and measure blood biomarkers at baseline, 3, 6, 12 and 18 months. The goals are to: (1) Determine the effect of interventions on blood biomarkers over 6 months; (2) Evaluate blood biomarkers as surrogate endpoints for predicting cognitive responses to interventions over 18 months; and (3; exploratory) Examine blood biomarkers as surrogate endpoints for predicting brain MRI biomarker responses to interventions over 18 months. Discussion: This study aims to identify new blood biomarkers that can track cognitive decline or AD-related brain atrophy among aMCI patients subjected to a regimen of aerobic exercise and cognitive training. Findings from this study will drive the further use of blood biomarkers in developing effective prevention and treatment strategies for AD dementia. Trial registration number: This study is an ancillary study of the ACT Trial which was registered with ClinicalTrials.gov, NCT03313895.

Abstract MYCN is a major driver for the childhood cancer, neuroblastoma, however, there are no inhibitors of this target. Enhanced MYCN protein stability is a key component of MYCN oncogenesis and is maintained by multiple feedforward expression loops involving MYCN transactivation target genes. Here, we reveal the oncogenic role of a novel MYCN target and binding protein, proliferation-associated 2AG4 (PA2G4). Chromatin immunoprecipitation studies demonstrated that MYCN occupies the PA2G4 gene promoter, stimulating transcription. Direct binding of PA2G4 to MYCN protein blocked proteolysis of MYCN and enhanced colony formation in a MYCN-dependent manner. Using molecular modeling, surface plasmon resonance, and mutagenesis studies, we mapped the MYCN–PA2G4 interaction site to a 14 amino acid MYCN sequence and a surface crevice of PA2G4. Competitive chemical inhibition of the MYCN–PA2G4 protein–protein interface had potent inhibitory effects on neuroblastoma tumorigenesis in vivo. Treated tumors showed reduced levels of both MYCN and PA2G4. Our findings demonstrate a critical role for PA2G4 as a cofactor in MYCN-driven neuroblastoma and highlight competitive inhibition of the PA2G4-MYCN protein binding as a novel therapeutic strategy in the disease. Significance: Competitive chemical inhibition of the PA2G4–MYCN protein interface provides a basis for drug design of small molecules targeting MYC and MYCN-binding partners in malignancies driven by MYC family oncoproteins.

Background There are no risk scores designed specifically for mortality risk prediction in unselected cardiac intensive care unit ( CICU ) patients. We sought to develop a novel CICU ‐specific risk score for prediction of hospital mortality using variables available at the time of CICU admission. Methods and Results A database of CICU patients admitted from January 1, 2007 to April 30, 2018 was divided into derivation and validation cohorts. The top 7 predictors of hospital mortality were identified using stepwise backward regression, then used to develop the Mayo CICU Admission Risk Score (M‐ CARS ), with integer scores ranging from 0 to 10. Discrimination was assessed using area under the receiver‐operator curve analysis. Calibration was assessed using the Hosmer–Lemeshow statistic. The derivation cohort included 10 004 patients and the validation cohort included 2634 patients (mean age 67.6 years, 37.7% females). Hospital mortality was 9.2%. Predictor variables included in the M‐ CARS were cardiac arrest, shock, respiratory failure, Braden skin score, blood urea nitrogen, anion gap and red blood cell distribution width at the time of CICU admission. The M‐ CARS showed a graded relationship with hospital mortality (odds ratio 1.84 for each 1‐point increase in M‐ CARS , 95% CI 1.78–1.89). In the validation cohort, the M‐ CARS had an area under the receiver‐operator curve of 0.86 for hospital mortality, with good calibration ( P =0.21). The 47.1% of patients with M‐ CARS <2 had hospital mortality of 0.8%, and the 5.2% of patients with M‐ CARS >6 had hospital mortality of 51.6%. Conclusions Using 7 variables available at the time of CICU admission, the M‐ CARS can predict hospital mortality in unselected CICU patients with excellent discrimination.

Abstract Background: Alzheimer’s disease (AD) is an epidemic with tremendous public health impacts because there are currently no disease-modifying therapeutics. Randomized controlled trials (RCTs) for prevention of AD dementia often use clinical endpoints that take years to manifest (e.g., cognition) or surrogate endpoints that are costly or invasive (e.g., magnetic resonance imaging [MRI]). Blood biomarkers represent a clinically applicable alternative surrogate endpoint for RCTs that would be both cost-effective and minimally invasive, but little is known about their value as surrogate endpoints for treatment responses in the prevention of AD dementia. Methods: The objective of this study is to investigate blood neuropathological, neurodegenerative, and neurotrophic biomarkers as surrogate endpoints for treatment responses to 3 interventions in older adults with amnestic mild cognitive impairment (aMCI, a prodromal stage of AD): aerobic exercise; cognitive training; and combined aerobic exercise and cognitive training (ACT). We chose these three sets of biomarkers for their unique mechanistic associations with AD pathology, neurodegeneration and neurogenesis. This study is built on the ACT Trial (1R01AG055469), a single-blinded, multi-site, 2×2 factorial Phase II RCT that examines the synergistic effects of a 6-month ACT intervention on cognition and MRI biomarkers (AD-signature cortical thickness and hippocampal volume) (n=128). In this ACT Trial Blood Biomarkers Study, we will enroll 120 ACT Trial aMCI participants and measure blood biomarkers at baseline, 3, 6, 12 and 18 months. The goals are to: (1) Determine the effect of interventions on blood biomarkers over 6 months; (2) Evaluate blood biomarkers as surrogate endpoints for predicting cognitive responses to interventions over 18 months; and (3; exploratory) Examine blood biomarkers as surrogate endpoints for predicting brain MRI biomarker responses to interventions over 18 months. Discussion: This study aims to identify new blood biomarkers that can track cognitive decline or AD-related brain atrophy among aMCI patients subjected to a regimen of aerobic exercise and cognitive training. Findings from this study will drive the further use of blood biomarkers in developing effective prevention and treatment strategies for AD dementia. Trial registration number: This study is an ancillary study of the ACT Trial which was registered with ClinicalTrials.gov, NCT03313895.

Background: We aim to study the incidence of major complications related to procedure defined as in-hospital death, myocardial infarction, stroke, pericardial effusion or tamponade, percutaneous coronary intervention due to iatrogenic coronary dissection, or unplanned bypass surgery within 72 hours after diagnostic left heart catheterization (LHC; primary end point). Furthermore, all causes of in-hospital death after LHC were adjudicated and reported (secondary end point). Methods and Results: Diagnostic LHC procedures (aortic angiography; coronary, including graft, angiography; and left ventricular angiography) from January 1, 2002, through December 31, 2013, were identified using the clinical scheduling system at Mayo Clinic, Rochester, and complications were identified through electronic records. International Classification of Diseases, Ninth Revision billing codes were used. Registration was queried to identify all-cause mortality. All events were reviewed and adjudicated. There were 43 786 diagnostic LHC procedures; 97.3% were coronary angiograms. The mean age of patients was 64.5 years (13.6), and the majority were male (61.5%). Primary end point was seen in 36 (0.082%) procedures or 8.2 of 10 000 LHCs. Combined right sided procedures with LHC did not increase the risk of major complications. Cardiogenic and septic shock, cardiac arrhythmia, and postsurgical complication were the most common causes of in-hospital death after LHC. Conclusions: The overall rates of major complications related to diagnostic cardiac catheterization procedures are extremely rare. The majority of the deaths occurring post-diagnostic LHC procedures were secondary to acute illness rather than directly related to diagnostic procedure.

Significance Glioblastoma, the most common and lethal of primary brain tumors, can diffusely infiltrate brain. Because the components of the cytoskeleton that drive tumor invasion are nonredundant, they have been attractive targets for blocking glioblastoma dispersion. However, we find that while targeting one of these—the molecular motor myosin IIA—effectively blocks glioblastoma invasion, it enhances tumor proliferation and lethality. In this study, we have found that myosin IIA functions as a tumor suppressor by reducing signaling of two oncogenes—ERK1/2 and NF-κB—in a manner regulated by the mechanics of the tumor and surrounding brain. Our results also argue that effective treatment of glioblastoma will require inhibiting targets that drive both invasion and proliferation.