Citations

Key Points Pembrolizumab was first shown to be clinically active in CLL patients with RT. PD-1 and PD-L1 expression in tumor microenvironment are promising biomarkers to select RT patients for PD-1 blockade.

Background: Hydrogen peroxide (H2O2)-induced oxidative stress has been demonstrated to induce afterdepolarizations and triggered activities in isolated myocytes, but the underlying mechanisms remain not fully understood. We aimed to explore whether protein kinase C (PKC) activation plays an important role in oxidative stress-induced afterdepolarizations. Methods: Action potentials and ion currents of isolated rabbit cardiomyocytes were recorded using the patch clamp technique. H2O2 (1 mM) was perfused to induce oxidative stress and the specific classical PKC inhibitor, Gö 6983 (1 μM), was applied to test the involvement of PKC. Results: H2O2 perfusion prolonged the action potential duration and induced afterdepolarizations. Pretreatment with Gö 6983 prevented the emergence of H2O2-induced afterdepolarizations. Additional application of Gö 6983 with H2O2 effectively suppressed H2O2-induced afterdepolarizations. H2O2 increased the late sodium current (INa,L) (n = 7, p < 0.01) and the L-type calcium current (ICa,L) (n = 5, p < 0.01), which were significantly reversed by Gö 6983 (p < 0.01). H2O2 also increased the transient outward potassium current (Ito) (n = 6, p < 0.05). However, Gö 6983 showed little effect on H2O2-induced enhancement of Ito. Conclusions: H2O2 induced afterdepolarizations via the activation of PKC and the enhancement of ICa,L and INa,L. These results provide evidence of a link between oxidative stress, PKC activation and afterdepolarizations.

Abstract Background: The utility of alpha-fetoprotein (AFP) for hepatocellular carcinoma (HCC) surveillance is controversial. We aimed to identify factors associated with elevated AFP and define the patients for whom AFP is effective for surveillance. Methods: Data from the NCI Early Detection Research Network phase II HCC biomarker study (233 early-stage HCC and 412 cirrhotic patients) were analyzed. We analyzed 110 early-stage HCC and 362 cirrhotic hepatitis C virus (HCV) patients for external validation. Sensitivity, specificity, and area under the ROC curve (AUC) for HCC were calculated. Results: HCV etiology, non-White race, and serum alanine transaminase (ALT) predicted elevated AFP in cirrhotics. Non-White race and ALT predicted elevated AFP in HCC patients. Higher AUC of AFP for HCC was noted in patients with HBV (0.85) and alcohol (0.84), whereas it was lower in patients with hepatitis C virus (HCV; 0.80) and nonviral/alcohol etiology (0.76). The AUC was higher in HCV patients with serum ALT ≤40 U/L than patients with serum ALT &gt;40 U/L (0.91 vs. 0.75, P &lt; 0.01). At 90% specificity, the sensitivity of AFP increased from 44% to 74% in Whites with HCV and from 50% to 85% in non-Whites with HCV. There was a trend toward higher AUC in HCV patients with serum ALT ≤40 U/L than those with serum ALT &gt;40 U/L (0.79 vs. 0.69, P = 0.10) in the validation cohort. Conclusions: The satisfactory performance of AFP in HCV patients with normal ALT should be further validated. Impact: The AFP may serve as a valuable surveillance test in HCV patients with normal ALT. Cancer Epidemiol Biomarkers Prev; 26(7); 1085–92. ©2017 AACR.

Respiratory motion is traditionally assessed using tumor motion magnitude. In proton therapy, respiratory motion causes density variations along the beam path that result in uncertainties of proton range. This work has investigated the use of water‐equivalent thickness (WET) to quantitatively assess the effects of respiratory motion on calculated dose in passively scattered proton therapy (PSPT). A cohort of 29 locally advanced non‐small cell lung cancer patients treated with 87 PSPT treatment fields were selected for analysis. The variation in WET (ΔWET) along each field was calculated between exhale and inhale phases of the simulation four‐dimensional computed tomography. The change in calculated dose (ΔDose) between full‐inhale and full‐exhale phase was quantified for each field using dose differences, 3D gamma analysis, and differential area under the curve (ΔAUC) analysis. Pearson correlation coefficients were calculated between ΔDose and ΔWET. Three PSPT plans were redesigned using field angles to minimize variations in ΔWET and compared to the original plans. The median ΔWET over 87 treatment fields ranged from 1‐9 mm, while the ΔWET 95th percentile value ranged up to 42 mm. The ΔWET was significantly correlated to the ΔDose for all metrics analyzed. The patient plans that were redesigned using ΔWET analysis to select field angles were more robust to the effects of respiratory motion, as ΔAUC values were reduced by more than 60% in all three cases. The tumor motion magnitude alone does not capture the potential dosimetric error due to respiratory motion because the proton range is sensitive to the motion of all patient anatomy. The use of ΔWET has been demonstrated to identify situations where respiratory motion can impact the calculated dose. Angular analysis of ΔWET may be capable of designing radiotherapy plans that are more robust to the effects of respiratory motion.PACS number(s): 87.55.‐x

ABSTRACT Hepatitis E virus (HEV) has emerged as a cause of chronic hepatitis among immunocompromised patients. Molecular assays have become important tools for the diagnosis and management of these chronically infected patients. A real-time reverse transcription-quantitative PCR (RT-qPCR) assay utilizing Pleiades probe chemistry and an RNA internal control for the simultaneous detection and quantification of HEV RNA in human serum was developed based on an adaptation of a previously described and broadly reactive primer set targeting the overlapping open reading frame 2/3 (ORF2/3) nucleotide sequence of HEV. A chimeric bovine viral diarrhea virus construct containing an HEV RNA insert (SynTura HEV) was developed, value assigned with the first World Health Organization (WHO) international standard for HEV RNA (code 6329/10), and used to prepare working assay calibrators and controls, which supported an assay quantification range of 100 to 5,000,000 IU/ml. The analytical sensitivity (95% detection rate) of this assay was 25.2 IU/ml (95% confidence interval [CI], 19.2 to 44.1 IU/ml). The assay successfully amplified 16 different HEV sequences with significant nucleotide mismatching in primer/probe binding regions, while evaluation of a WHO international reference panel for HEV genotypes (code 8578/13) showed viral load results falling within the result ranges generated by WHO collaborative study participants for all panel members (genotypes 1 to 4). Broadly reactive RT-qPCR primers targeting HEV ORF2/3 were successfully adapted for use in an assay based on Pleiades probe chemistry. The availability of secondary standards calibrated to the WHO HEV international standard can improve the standardization and performance of assays for the detection and quantification of HEV RNA.

SummarySimtuzumab, a monoclonal antibody inhibitor of extracellular matrix enzyme lysyl oxidase‐like‐2, showed preclinical promise and was well tolerated in clinical studies. A phase 2, open‐label study of simtuzumab was conducted in patients with primary myelofibrosis (MF), post‐polycythaemia vera MF and post‐essential thrombocythaemia MF. Fifty‐four patients were randomized to receive simtuzumab alone (200 or 700 mg [n = 12 each group]) or simtuzumab (200 or 700 mg) with ruxolitinib (n = 15 each group) for 24 weeks. Simtuzumab alone or in combination with ruxolitinib showed no clinical benefit at 24 weeks. The mean serum simtuzumab trough concentrations appeared to increase dose‐proportionally between the 200‐mg and 700‐mg treatment groups. Therapy‐related serious adverse events were pyrexia, pain in extremity (both in 1 patient) and infusion reaction (in another patient). Bone marrow fibrosis (BMF) score was reduced at 24 weeks in 2 patients (16·7%) in the simtuzumab 700‐mg group, 1 (6·7%) in the simtuzumab 200‐mg + ruxolitinib group, and 2 (13·3%) in the simtuzumab 700‐mg + ruxolitinib group; similar numbers of patients had increased BMF. Simtuzumab alone or with ruxolitinib was well tolerated but did not produce clinical benefit nor consistently reduce BMF in patients with MF by 24 weeks.

AbstractObjectivesTo analyze the economic impact of testing for activated protein C resistance (APC-R) due to factor V Leiden (FVL) mutation with APC-R with reflexive FVL genotyping (algorithmic approach) or genotyping alone.MethodsOptumLabs Data Warehouse (OLDW) data were used to assess testing approaches. Insurance claims for APC-R and FVL in 2013 were compared with the Mayo Clinic database. Centers for Medicare & Medicaid Services diagnostic fee schedules were used to assign costs.ResultsOf 19.3 million OLDW-covered individuals, 74,242 (0.385%) received 75,608 tests: APC-R, 2,265 (2.9%); FVL genotyping, 70,619 (90.1%); and both APC-R and FVL, 2,724 (7.0%). In total, 1,317 tests were performed at Mayo Clinic: APC-R with reflex FVL (1,256; 95.4%) and FVL alone (61; 4.6%). Costs per evaluated individual and per total population (person/year) in OLDW and algorithmic approach were $83.77 vs $36.38 and $0.32 vs $0.14, respectively.ConclusionsThe cost-optimized algorithmic approach reduces health care costs.