Objective Septic shock heterogeneity has important implications for clinical trial implementation and patient management. We previously addressed this heterogeneity by identifying 3 putative subclasses of children with septic shock based exclusively on a 100-gene expression signature. Here we attempted to prospectively validate the existence of these gene expression-based subclasses in a validation cohort. Design Prospective observational study involving microarray-based bioinformatics. Setting Multiple pediatric intensive care units in the United States. Patients Separate derivation (n=98) and validation (n=82) cohorts of children with septic shock. Interventions None other than standard care. Measurements and Main Results Gene expression mosaics of the 100 class-defining genes were generated for 82 individual patients in the validation cohort. Using computer-based image analysis, patients were classified into 1 of 3 subclasses (“A”, “B”, or “C”) based on color and pattern similarity relative to reference mosaics generated from the original derivation cohort. After subclassification, the clinical database was mined for phenotyping. Subclass A patients had higher illness severity relative to subclasses B and C, as measured by maximal organ failure, fewer ICU-free days, and a higher PRISM score. Patients in subclass A were characterized by repression of genes corresponding to adaptive immunity and glucocorticoid receptor signaling. Separate subclass assignments were conducted by 21 individual clinicians, using visual inspection. The consensus classification of the clinicians had modest agreement with the computer algorithm. Conclusions We have validated the existence of subclasses of children with septic shock based on a biologically relevant, 100-gene expression signature. The subclasses have relevant clinical differences.

IntroductionMost breast cancers that occur in women with germline BRCA1 mutations are estrogen receptor-negative (ER-) and also typically lack expression of progesterone receptor (PR) and HER2 overexpression. We undertook a study to assess the clinical factors that predict for an estrogen receptor positive (ER+) breast cancer in BRCA1 mutation carriers and to characterize the pathologic features of these tumors.MethodsClinical characteristics of BRCA1 carriers with 58 ER+ and 114 ER- first invasive breast cancers were compared. Pathologic features of BRCA1 ER+ cancers were compared to those of BRCA1 ER- cancers and to age-matched ER+ sporadic cancers.ResultsBRCA1 carriers aged ≥ 50 at diagnosis of first invasive breast cancer were more likely to have an ER+ cancer compared to those aged < 50 (57% vs 29%, P = 0.005). ER+ BRCA1 cancers were less likely than ER- BRCA1 cancers to have "BRCA-associated" features such as high mitotic activity, geographic necrosis/fibrotic focus, and pushing margins (RR 0.06, 0.22, 0.24; P < 0.001, 0.02, 0.03 respectively). When compared to sporadic ER+ cancers, ER+ BRCA1 cancers were more often of invasive ductal type (RR 2.4, P = 0.03), with a high mitotic rate (RR 5.0, P = 0.006) and absent or mild lymphocytic infiltrate (RR 10.2, P = 0.04).ConclusionsBRCA1 carriers who are older at first breast cancer diagnosis are more likely to have ER+ tumors than younger BRCA1 carriers. These ER+ cancers appear pathologically "intermediate" between ER- BRCA1 cancers and ER+ sporadic breast cancers raising the possibility that either some ER+ BRCA1 cancers are incidental or that there is a unique mechanism by which these cancers develop.

Objective-To frame the general process of biomarker discovery and development, and to describe a proposal for the development of a multi-biomarker based risk model for pediatric septic shock.Data Source-Narrative literature review and author generated data.Main Results-Biomarkers can be grouped into four broad classes, based on the intended function: diagnostic, monitoring, surrogate, and stratification. Biomarker discovery and development requires a rigorous process, which is frequently not well followed in the critical care medicine literature. Very few biomarkers have successfully transitioned from the candidate stage to the true biomarker stage. There is great interest in developing diagnostic and stratification biomarkers for sepsis. Procalcitonin is currently the most promising diagnostic biomarker for sepsis. Recent evidence suggests that interleukin-8 can be used to stratify children with septic shock having a high likelihood of survival with standard care. Currently, there is a multiinstitutional effort to develop a multi-biomarker based sepsis risk model intended to predict outcome and illness severity for individual children with septic shock.Conclusions-Biomarker discovery and development is an important portion of the pediatric critical care medicine translational research agenda. This effort will require collaboration across multiple institutions and investigators. Rigorous conduct of biomarker-focused research holds the promise of transforming our ability to care for individual patients and our ability to conduct clinical trials in a more effective manner.

Purpose:To compare the clinical, imaging, and histopathologic features of breast cancers detected at screening magnetic resonance (MR) imaging, screening mammography, and those detected between screening examinations (interval cancers) in women at high risk. Materials and Methods:This retrospective institutional review board-approved, HIPAA-compliant review of 7519 women at high risk for breast cancer who underwent screening with MR imaging and mammography between January 2005 and December 2010 was performed to determine the number of screeningdetected and interval cancers diagnosed. The need for informed consent was waived. Medical records were reviewed for age, risk factors (family or personal history of breast cancer, BRCA mutation status, history of high-risk lesion or mantle radiation), tumor histopathologic results, and time between diagnosis of interval cancer and most recent screening examination. The x 2 test and logistic regression methods were used to compare the features of screening MR imaging, screening mammography, and interval cancers. The Wilcoxon signed-rank test was used to calculate P values. Results:A total of 18 064 screening MR imaging examinations and 26 866 screening mammographic examinations were performed. Two hundred twenty-two cancers were diagnosed in 219 women, 167 (75%) at MR imaging, 43 (19%) at mammography, and 12 (5%) interval cancers. Median age at diagnosis was 52 years. No risk factors were associated with screening MR imaging, screening mammography, or interval cancer (P . .06). Cancers found at screening MR imaging were more likely to be invasive cancer (118 of 167 [71%]; P , .0001). Of the 43 cancers found at screening mammography, 38 (88%) manifested as calcifications and 28 (65%) were ductal carcinoma in situ. Interval cancers were associated with nodal involvement (P = .005) and the triple-negative subtype (P = .03). Conclusion:In women at high risk for breast cancer who underwent screening with mammography and MR imaging, invasive cancers were more likely to be detected at MR imaging, whereas most cancers detected at screening mammography were ductal carcinoma in situ. Interval cancers were found infrequently and were more likely to be node positive and of the triple-negative subtype.q RSNA, 2016

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a nuclear receptor that requires ligand activation for transcription. Experimental studies have shown that 15-deoxy-Delta-PGJ2 (15d-PGJ2) is a natural PPARgamma ligand which has potent anti-inflammatory properties. This study was designed to examine the effect and the molecular mechanisms of 15d-PGJ2 on tissue neutrophil infiltration and survival in endotoxic shock. Male Swiss albino mice were subjected to intraperitoneal injection of Escherichia coli lipopolysaccharide (LPS, 25 mg/kg). Three hours after LPS mice received vehicle or 15d-PGJ2 (1 mg/kg) and continued treatment every 12 hours. Survival was monitored for 72 hours. In a separate experiment, mice were sacrificed 6 hours after LPS and tissue examined. In vehicle-treated mice, LPS injection resulted in a survival rate of 9%. Marked lung injury was characterized by hemorrhage, infiltration of inflammatory cells and reduction of alveolar space. Elevated levels of myeloperoxidase activity in lung and small intestine were indicative of infiltration of neutrophils. Increased expression of intercellular adhesion molecule-1, vascular cellular adhesion molecule-1 and E-selectin were observed in the lung and small intestine. These inflammatory events were associated with reduced expression of PPARgamma and with activation of nuclear factor-kappaB (NF-kappaB) in the lung. Treatment with 15d-PGJ2 improved survival rate to 55%, downregulated expression of adhesion molecules and reduced neutrophil infiltration in tissues. These beneficial effects were associated with reduced activation of NF-kappaB DNA binding, whereas expression and DNA binding of PPARgamma and expression of the cytoprotective heat shock protein (HSP) 70 were increased in the lung. Our data demonstrate that 15d-PGJ2 ameliorates endotoxic shock most likely through repressing the proinflammatory pathway of NF-kappaB and enhancement of the cytoprotective heat shock response.

Objective-To develop a clinically feasible stratification strategy for pediatric septic shock using gene expression mosaics and a 100-gene signature representing the first 24 hours of admission to the pediatric intensive care unit.Design-Prospective observational study involving microarray-based bioinformatics. Setting-Multiple pediatric intensive care units in the United States.Patients-Ninety-eight children with septic shock. Interventions-None other than standard care.Measurements and Main Results-Patients were classified into 3 previously published, genome-wide, expression-based sub-classes (sub-classes A, B, and C) having clinically relevant phenotypic differences. The class-defining 100-gene signature was depicted for each individual patient using mosaics generated by the Gene Expression Dynamics Inspector (GEDI). Composite mosaics were generated representing the average expression patterns for each of the 3 sub-classes. Nine individual clinicians served as blinded evaluators. Each evaluator was shown the 98 individual patient mosaics and asked to classify each patient into one of the three sub-classes using the composite mosaics as the reference point. The respective sensitivities, specificities, positive predictive values, and negative predictive values of the sub-classification strategy were ≥84% across the 3 sub-classes. The classification strategy also generated positive likelihood ratios ≥16.8 and negative likelihood ratios ≤0.2 across the three sub-classes. The kappa coefficient across all possible inter-evaluator comparisons was 0.81.Conclusions-We have provided initial evidence (proof of concept) for a clinically feasible and robust stratification strategy for pediatric septic shock based on a 100 gene signature and gene expression mosaics.

These data provide new in vivo evidence for an antiinflammatory role for SP-D in response to noninfectious, subacute lung injury via modulation of oxidative-nitrative stress.

Objective: To determine the performance of a targeted microarray-based cell-free DNA (cfDNA) test (Harmony Prenatal Test®) for the identification of pregnancies at increased risk for 22q11.2 deletion. Methods: Test performance was determined in 2 steps including a total of 1,953 plasma samples. Analytical validation was performed in 1,736 plasma samples. Clinical verification of performance was performed in an additional 217 prospectively ascertained samples from pregnancies with fetal deletion status determined by diagnostic testing. Results: Analytical sensitivity was 75.4% (95% CI: 67.1–82.2%) based on 122 samples with deletions ranging from 1.96 to 3.25 Mb. In 1,614 presumed unaffected samples, specificity was determined to be at least 99.5% (95% CI: 99.0–99.7%). In the clinical cohort, 5 of 7 samples from pregnancies affected with 22q11.2 deletion were determined to have a high probability of deletion. There were no false positive results in the 210 unaffected samples in this cohort. These clinical data are consistent with the performance demonstrated in the analytical validation. Conclusions: cfDNA testing using a targeted microarray-based technology is able to identify pregnancies at increased risk for 22q11.2 deletions of 3.0 Mb and smaller while maintaining a low false positive rate.