Citations

AbstractIntroductionAlzheimer's Disease Neuroimaging Initiative (ADNI) is now in its 10th year. The primary objective of the magnetic resonance imaging (MRI) core of ADNI has been to improve methods for clinical trials in Alzheimer's disease (AD) and related disorders.MethodsWe review the contributions of the MRI core from present and past cycles of ADNI (ADNI‐1, ‐Grand Opportunity and ‐2). We also review plans for the future‐ADNI‐3.ResultsContributions of the MRI core include creating standardized acquisition protocols and quality control methods; examining the effect of technical features of image acquisition and analysis on outcome metrics; deriving sample size estimates for future trials based on those outcomes; and piloting the potential utility of MR perfusion, diffusion, and functional connectivity measures in multicenter clinical trials.DiscussionOver the past decade the MRI core of ADNI has fulfilled its mandate of improving methods for clinical trials in AD and will continue to do so in the future.

Abstract Ovarian cancer (OC) is the fifth leading cause of cancer death in women in the US. Müllerian inhibiting substance (MIS) is a glycoprotein hormone that causes Müllerian duct regression through a complex of TGF- β family homologous receptors: a type II ligand-binding receptor (T2R) and a tissue-specific type I receptor (T1R) that initiates downstream signaling. MIS has been proposed as potential therapeutic agent in OC. We have previously shown that specific combination of T2R/T1R receptors are expressed on OC cells, however data is lacking on the MIS-dependent pathways activated in OC cells in a T1R-specific manner. These limitations hinder further development of MIS as a therapy. We sought to determine the downstream signaling pathways activated by MIS in a T1R specific manner. We designed a chimeric OC cell model system in which GM-CSF can function as the ligand to specifically activate candidate T2R/T1R combinations (MISRII with either ALK2, ALK3, or ALK6). RNA-Seq technology was used to identify differentially expressed early and late response genes. Over 15,032 genes were analyzed, restricted to genes in which there were > 32 counts for duplicate samples. Pathway analysis was performed using Ingenuity's Integrative Pathway Analysis Tool (IPA) for genes which were expressed over 2 fold, with an False Discovery Rate (FDR)<0.1 and log (Counts per Million, CPM)>-0.001. We observed 56, 37, and 51 early response (1hr) genes which were up- or down-regulated after stimulation in OC cells engineered to express either ALK2, ALK3, and ALK6, respectively. We identified a subset of 18 of genes (e.g., ID1, SMAD7, FOSB) which were upregulated after treatment in all MISRII/T1R combinations, suggesting redundancy amongst the three T1R partner receptors. These observations will be confirmed by RT-qPCR and immunoblotting. A majority of these redundant genes are known to play roles in TGF-β signaling and cell proliferation pathways. Importantly, as we have previously shown that not all T1R candidates are expressed in OC, we report subsets of genes (e.g., RASSF6, C/EBPBβ, CSMD3) which were uniquely altered after stimulation only in the presence of a specific T1R. This indicates specific pathway activation is dependent upon T1R expression pattern in OC and likely determines response. In addition to previously known TGF- β signaling pathway, we found gene signatures (e.g. FOSB, RASSF6, LRP1B, ID1) suggesting pathways which affect cell proliferation, apoptosis, chemotherapy resistance, and DNA repair in response to MIS. This is the first study to begin to define the specific roles candidate T1R's play in signaling in response to MIS in an OC model. An understanding of these pathways is a necessary prerequisite to examining MIS as a therapy. These preliminary data suggest a role for MIS in apoptosis, cytotoxic drug resistance and DNA repair. This can be used to test combination therapy with currently available drugs and MIS in OC treatment. Citation Format: Qing Zhang, Eati Basal, Jaime I. Davila, Xueqian Yin, Edward B. Leof, William A. Cliby. Comparative RNA-Seq analysis of MIS signaling: Potential relevance as therapeutic strategy in ovarian cancer treatment. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3462. doi:10.1158/1538-7445.AM2014-3462

ABSTRACTCarpal tunnel syndrome (CTS) is a peripheral neuropathy characterized by non‐inflammatory fibrosis of the subsynovial connective tissues (SSCT). A rabbit model of CTS was developed to test the hypothesis that SSCT fibrosis causes the neuropathy. We used a cell‐seeded collagen‐gel contraction model to characterize the fibrosis in this model in terms of cellular mechanics, specifically to compare the ability of SSCT cells from the rabbit model and normal rabbits to contract the gel, and to assess the effect of transforming growth factor‐β1,which is upregulated in CTS, on these cells. SSCT fibrosis was induced in six retired breeder female rabbits which were sacrificed at 6 weeks (N = 3) and 12 weeks (n = 3). An additional two rabbits served as controls. SSCT was harvested according to a standard protocol. Gels seeded with SSCT cells from rabbits sacrificed at 6 weeks had significantly higher tensile strength (p < 0.001) and Young's modulus (p < 0.001) than gels seeded with cells from rabbits sacrificed at 12 weeks or control animals. TGF‐β1 significantly increased the decay time constant (p < 0.001), tensile strength (p < 0.001), and Young's modulus (p < 0.001) regardless of the cell source. This model may be useful in screening therapeutic agents that may block SSCT fibrosis, identifying possible candidates for CTS treatment. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:668–674, 2015.

Abstract IL-17 is known to play important roles in immune and inflammatory disease, such as in asthma, but its functions in allergic airway inflammation are still controversial, and the molecular mechanisms mediating these functions remain unclear. Increased production of eosinophils in bone marrow and their emergence in the airway have been linked to the onset and progression of allergic asthma. In this study, we investigated the effects of exogenous IL-17 on allergic airway inflammation and explored the underlying molecular mechanisms through eosinophil generation. Exogenous IL-17 significantly attenuated the features of allergic inflammation induced by ovalbumin in mice. It inhibited eosinophil differentiation both in vivo and in vitro, accompanied by down-regulated expression of CC chemokine receptor 3, GATA binding protein 1 (GATA-1), and GATA binding protein 2 (GATA-2), as well as reduced formation of common myeloid progenitors and eosinophil progenitors, but without influencing eosinophil apoptosis. IL-17 also significantly decreased the number of eosinophils in IL-5–transgenic mice, although it notably increased the levels of IL-3, IL-5, and granulocyte/macrophage colony–stimulating factor. In addition, IL-17 had little effect on secretion of the inflammatory cytokines by eosinophils. Neutralization of endogenous IL-17 significantly augmented eosinophil recruitment in the airways. Together, these findings suggest that exogenous IL-17 protects against allergic airway inflammation, most likely through inhibition of the eosinophil differentiation in bone marrow.

ABSTRACTFibrosis of the subsynovial connective tissue (SSCT) is a predominant feature of carpal tunnel syndrome (CTS). While the nature of CTS has been extensively studied, little is known about the etiology of this disease. We investigated SSCT tissue from patients with CTS and control subjects using fibrosis arrays and cell culture analysis. Twofold changes in fibrotic gene expression were found in multiple genes from patient SSCT using fibrosis arrays. This data was confirmed via qRT‐PCR on a subset of genes; collagen I (Col1), collagen III (Col3), connective tissue growth factor (CTGF), transforming growth factor β (TGF‐β), and SMAD3 (P < 0.05) which significantly corroborate the fold changes found in the fibrosis arrays. To further explore the nature of SSCT fibrosis, cells were isolated from patient and control tissue. Col1, Col3, TGF‐β, and SMAD3 were highly expressed in patient SSCT fibroblasts as compared to control (P < 0.05). Further, fibrotic genes expression was decreased by inhibiting TGF‐β receptor I (TβRI) activity (P < 0.05). TGF‐β second messenger SMAD activity was significantly activated in SSCT fibroblasts from patients and this activation was abrogated by inhibiting TβRI signaling (P < 0.05). These findings suggest that blocking TGF‐β signaling may be an important therapeutic approach to treating the underlying fibrosis of SSCT in CTS patients. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1444–1450, 2014.

Abstract Objectives Drug repurposing, which finds new indications for existing drugs, has received great attention recently. The goal of our work is to assess the feasibility of using electronic health records (EHRs) and automated informatics methods to efficiently validate a recent drug repurposing association of metformin with reduced cancer mortality. Methods By linking two large EHRs from Vanderbilt University Medical Center and Mayo Clinic to their tumor registries, we constructed a cohort including 32 415 adults with a cancer diagnosis at Vanderbilt and 79 258 cancer patients at Mayo from 1995 to 2010. Using automated informatics methods, we further identified type 2 diabetes patients within the cancer cohort and determined their drug exposure information, as well as other covariates such as smoking status. We then estimated HRs for all-cause mortality and their associated 95% CIs using stratified Cox proportional hazard models. HRs were estimated according to metformin exposure, adjusted for age at diagnosis, sex, race, body mass index, tobacco use, insulin use, cancer type, and non-cancer Charlson comorbidity index. Results Among all Vanderbilt cancer patients, metformin was associated with a 22% decrease in overall mortality compared to other oral hypoglycemic medications (HR 0.78; 95% CI 0.69 to 0.88) and with a 39% decrease compared to type 2 diabetes patients on insulin only (HR 0.61; 95% CI 0.50 to 0.73). Diabetic patients on metformin also had a 23% improved survival compared with non-diabetic patients (HR 0.77; 95% CI 0.71 to 0.85). These associations were replicated using the Mayo Clinic EHR data. Many site-specific cancers including breast, colorectal, lung, and prostate demonstrated reduced mortality with metformin use in at least one EHR. Conclusions EHR data suggested that the use of metformin was associated with decreased mortality after a cancer diagnosis compared with diabetic and non-diabetic cancer patients not on metformin, indicating its potential as a chemotherapeutic regimen. This study serves as a model for robust and inexpensive validation studies for drug repurposing signals using EHR data.

Background. Dilated cardiomyopathy (DCM) is one of the leading causes of heart failure with high morbidity and mortality. Although more than 40 genes have been reported to cause DCM, the role of genetic testing in clinical practice is not well defined. Mutations in the troponin T (TNNT2) gene represent an important subset of known disease-causing mutations associated with DCM. Therefore, the aim of the present study was to determine the genetic variations inTNNT2and the associations of those variations with DCM in Chinese patients.Methods. An approximately 4 kb fragment of theTNNT2gene was isolated from 103 DCM patients and 192 healthy controls and was analyzed by DNA sequence analysis for genetic variations.Results. A total of 6TNNT2mutations were identified in 99 patients, including a G321T missense mutation (Leu84Phe) and 5 novel intronic mutations. Alleles of two novel SNPs (c.192+353C>A, OR=0.095, 95% CI:0.013–0.714,P=0.022; c.192+463G>A, OR=0.090, 95% CI:0.012–0.675,P=0.019) and SNP rs3729843 (OR=1.889, 95% CI:1.252–2.852;P=0.002) were significantly correlated with DCM.Conclusions. These results suggest that the missense mutation (Leu84Phe) and two novel SNPs (c.192+353C>A, c.192+463G>A) inTNNT2gene might be associated with DCM in the Chinese population.

Wheezing is a major long-term respiratory morbidity in preterm infants with and without bronchopulmonary dysplasia. We hypothesized that mild vs. severe hyperoxic exposure in neonatal mice differentially affects airway smooth muscle hypertrophy and resultant airway reactivity. Newborn mice were exposed to 7 days of mild (40% oxygen) or severe (70% oxygen) hyperoxia vs. room air controls. Respiratory system resistance (Rrs), compliance (Crs), and airway reactivity were measured 14 days after oxygen exposure ended under ketamine/xylazine anesthesia. Baseline Rrs increased and Crs decreased in both treatment groups. Methacholine challenge dose dependently increased Rrs and decreased Crs in 40% oxygen-exposed mice, whereas Rrs and Crs responses were similar between 70% oxygen-exposed and normoxic controls. Airway smooth muscle thickness was increased in 40%- but not 70%-exposed mice, whereas collagen increased and both alveolar number and radial alveolar counts decreased after 40% and 70% oxygen. These data indicate that severity of hyperoxia may differentially affect structural and functional changes in the developing mouse airway that contribute to longer-term hyperreactivity. These findings may be important to our understanding of the complex role of neonatal supplemental oxygen therapy in postnatal development of airway responsiveness.

Abstract Asthma and mouse models of allergic respiratory inflammation are invariably associated with a pulmonary eosinophilia; however, this association has remained correlative. In this report, a causative relationship between eosinophils and allergen-provoked pathologies was established using eosinophil adoptive transfer. Eosinophils were transferred directly into the lungs of either naive or OVA-treated IL-5−/− mice. This strategy resulted in a pulmonary eosinophilia equivalent to that observed in OVA-treated wild-type animals. A concomitant consequence of this eosinophil transfer was an increase in Th2 bronchoalveolar lavage cytokine levels and the restoration of intracellular epithelial mucus in OVA-treated IL-5−/− mice equivalent to OVA-treated wild-type levels. Moreover, the transfer also resulted in the development of airway hyperresponsiveness. These pulmonary changes did not occur when eosinophils were transferred into naive IL-5−/− mice, eliminating nonspecific consequences of the eosinophil transfer as a possible explanation. Significantly, administration of OVA-treated IL-5−/− mice with GK1.5 (anti-CD4) Abs abolished the increases in mucus accumulation and airway hyperresponsiveness following adoptive transfer of eosinophils. Thus, CD4+ T cell-mediated inflammatory signals as well as signals derived from eosinophils are each necessary, yet alone insufficient, for the development of allergic pulmonary pathology. These data support an expanded view of T cell and eosinophil activities and suggest that eosinophil effector functions impinge directly on lung function.