RNF43 inhibits WNT5A-driven signaling and suppresses melanoma invasion and resistance to the targeted therapy

RNF43 is an E3 ubiquitin ligase and known negative regulator of WNT/β-catenin signaling. We demonstrate that RNF43 is also a regulator of noncanonical WNT5A-induced signaling in human cells. Analysis of the RNF43 interactome using BioID and immunoprecipitation showed that RNF43 can interact with the core receptor complex components dedicated to the noncanonical Wnt pathway such as ROR1, ROR2, VANGL1, and VANGL2. RNF43 triggers VANGL2 ubiquitination and proteasomal degradation and clathrin-dependent internalization of ROR1 receptor and inhibits ROR2 activation. These activities of RNF43 are physiologically relevant and block pro-metastatic WNT5A signaling in melanoma. RNF43 inhibits responses to WNT5A, which results in the suppression of invasive properties of melanoma cells. Furthermore, RNF43 prevented WNT5A-assisted development of resistance to BRAF V600E and MEK inhibitors. Next, RNF43 acted as melanoma suppressor and improved response to targeted therapies in vivo. In line with these findings, RNF43 expression decreases during melanoma progression and RNF43-low patients have a worse prognosis. We conclude that RNF43 is a newly discovered negative regulator of WNT5A-mediated biological responses that desensitizes cells to WNT5A.

MEIS-WNT5A axis regulates development of fourth ventricle choroid plexus

The choroid plexus (ChP) produces cerebrospinal fluid and forms an essential brain barrier. ChP tissues form in each brain ventricle, each one adopting a distinct shape, but remarkably little is known about the mechanisms underlying ChP development. Here, we show that epithelial WNT5A is crucial for determining fourth ventricle (4V) ChP morphogenesis and size in mouse. Systemic Wnt5a knockout, or forced Wnt5a overexpression beginning at embryonic day 10.5, profoundly reduced ChP size and development. However, Wnt5a expression was enriched in Foxj1-positive epithelial cells of 4V ChP plexus, and its conditional deletion in these cells affected the branched, villous morphology of the 4V ChP. We found that WNT5A was enriched in epithelial cells localized to the distal tips of 4V ChP villi, where WNT5A acted locally to activate non-canonical WNT signaling via ROR1 and ROR2 receptors. During 4V ChP development, MEIS1 bound to the proximal Wnt5a promoter, and gain- and loss-of-function approaches demonstrated that MEIS1 regulated Wnt5a expression. Collectively, our findings demonstrate a dual function of WNT5A in ChP development and identify MEIS transcription factors as upstream regulators of Wnt5a in the 4V ChP epithelium.

A cellular and spatial map of the choroid plexus across brain ventricles and ages

The choroid plexus (ChP) in each brain ventricle produces cerebrospinal fluid (CSF) and forms the blood-CSF barrier. Here, we construct a single-cell and spatial atlas of each ChP in the developing, adult, and aged mouse brain. We delineate diverse cell types, subtypes, cell states, and expression programs in epithelial and mesenchymal cells across ages and ventricles. In the developing ChP, we predict a common progenitor pool for epithelial and neuronal cells, validated by lineage tracing. Epithelial and fibroblast cells show regionalized expression by ventricle, starting at embryonic stages and persisting with age, with a dramatic transcriptional shift with maturation, and a smaller shift in each aged cell type. With aging, epithelial cells upregulate host-defense programs, and resident macrophages upregulate interleukin-1β (IL-1β) signaling genes. Our atlas reveals cellular diversity, architecture and signaling across ventricles during development, maturation, and aging of the ChP-brain barrier.

Community resilience in a rural food system: documenting pathways to nutrition solutions

OBJECTIVE

To describe and determine the barriers and facilitators to food-related health behaviors of residents in a rural Mississippi Delta community.

STUDY DESIGN

Descriptive study of qualitative interviews.

METHODS

A non-random sample of 34 low-income, food-insecure adults residing in a rural Mississippi Delta community were interviewed using fuzzy cognitive mapping, a mixed methods approach.

RESULTS

Participants strongly emphasized the time restraints they faced in both procuring and preparing foods, due to substantial travel time required to procure groceries. Participants also identified key facilitators to healthy eating behaviors, including seasonal produce stands, foraging, fishing, home provisioning, and access to the local food pantry. These barriers and facilitators are highly interconnected with other influential factors including poverty, lack of health care, unemployment, and faith-based support systems.

CONCLUSIONS

While the connection between low food access and poor eating habits is well researched, this novel mixed-method approach details two important elements missing from the literature: (1) other factors often overlooked that mitigate or exacerbate this relationship and (2) the dynamic nature of the relationships between these factors, poor eating habits, and health. Additionally, this research examines these relationships in an underrepresented rural minority population where resources needed to mitigate poor health are often much more limited. Findings from this study are critical to health and food policy in Mississippi and more generally, rural communities.

Choroid Plexus: The Orchestrator of Long-Range Signalling Within the CNS

Cerebrospinal fluid (CSF) is the liquid that fills the brain ventricles. CSF represents not only a mechanical brain protection but also a rich source of signalling factors modulating diverse processes during brain development and adulthood. The choroid plexus (CP) is a major source of CSF and as such it has recently emerged as an important mediator of extracellular signalling within the brain. Growing interest in the CP revealed its capacity to release a broad variety of bioactive molecules that, via CSF, regulate processes across the whole central nervous system (CNS). Moreover, CP has been also recognized as a sensor, responding to altered composition of CSF associated with changes in the patterns of CNS activity. In this review, we summarize the recent advances in our understanding of the CP as a signalling centre that mediates long-range communication in the CNS. By providing a detailed account of the CP secretory repertoire, we describe how the CP contributes to the regulation of the extracellular environment-in the context of both the embryonal as well as the adult CNS. We highlight the role of the CP as an important regulator of CNS function that acts via CSF-mediated signalling. Further studies of CP-CSF signalling hold the potential to provide key insights into the biology of the CNS, with implications for better understanding and treatment of neuropathological conditions.

Implementation of a Talbot-Lau x-ray deflectometer diagnostic platform for the OMEGA EP laser

A Talbot-Lau X-ray Deflectometer (TXD) was implemented in the OMEGA EP laser facility to characterize the evolution of an irradiated foil ablation front by mapping electron densities >10²² cm^-3 by means of Moiré deflectometry. The experiment used a short-pulse laser (30-100 J, 10 ps) and a foil copper target as an x-ray backlighter source. In the first experimental tests performed to benchmark the diagnostic platform, grating survival was demonstrated and x-ray backlighter laser parameters that deliver Moiré images were described. The necessary modifications to accurately probe the ablation front through TXD using the EP-TXD diagnostic platform are discussed.

A PBX1 transcriptional network controls dopaminergic neuron development and is impaired in Parkinson's disease

Pre-B-cell leukemia homeobox (PBX) transcription factors are known to regulate organogenesis, but their molecular targets and function in midbrain dopaminergic neurons (mDAn) as well as their role in neurodegenerative diseases are unknown. Here, we show that PBX1 controls a novel transcriptional network required for mDAn specification and survival, which is sufficient to generate mDAn from human stem cells. Mechanistically, PBX1 plays a dual role in transcription by directly repressing or activating genes, such as Onecut2 to inhibit lateral fates during embryogenesis, Pitx3 to promote mDAn development, and Nfe2l1 to protect from oxidative stress. Notably, PBX1 and NFE2L1 levels are severely reduced in dopaminergic neurons of the substantia nigra of Parkinson's disease (PD) patients and decreased NFE2L1 levels increases damage by oxidative stress in human midbrain cells. Thus, our results reveal novel roles for PBX1 and its transcriptional network in mDAn development and PD, opening the door for new therapeutic interventions.

Abstract P6-12-13: Awareness and acceptability of skin application of preventive medications for breast cancer

OBJECTIVE: To better understand women's knowledge and perceptions of breast cancer prevention medications and determine if a topical administration of these medications would increase acceptability.

METHODS: Focus groups were conducted with healthy women identified through the breast center of a single institution. An experienced moderator led participants through a discussion of breast cancer risk perceptions, knowledge of and concerns about risk reduction medications, and their views of a skin application of risk reducing medication. Participants provided sociodemographic information, breast cancer risk factors, and prior physician recommendations to take risk-reducing medicines. Trained research personnel examined all qualitative results systematically. Participants' breast cancer risk was estimated using the Gail Model.

RESULTS: Four focus groups (N=32) were conducted. Most participants had at least a college degree (78.2%) and were of either European (50%) or African ancestry (31%). The majority (72%) were at elevated risk for breast cancer, just over half of these women perceived themselves to be at higher than average risk. Only 19% of participants had prior knowledge of preventive medications. Women who perceived themselves to be at high risk were more likely to know about preventive medications than those who did not, 38% vs 0% respectively. Over 90% of the focus group participants stated that they would prefer a topical application of a preventive medication to a pill if their physician advised them to take preventive medication.

CONCLUSION: Awareness of preventive medications was low even in a highly educated sample of high-risk women. If given a choice in the route of administration of chemoprevention, nine out of ten women preferred a gel to a pill. Future work should focus on demonstrating a reduction in side effects of topical over oral medications and raising awareness of chemopreventive options for breast cancer to increase acceptance of preventive medications.

Citation Format: Karavites LC, Allu S, Khan SA, Kaiser K. Awareness and acceptability of skin application of preventive medications for breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-12-13.

Simplified protocol for flow cytometry analysis of fluorescently labeled exosomes and microvesicles using dedicated flow cytometer

Flow cytometry is a powerful method, which is widely used for high-throughput quantitative and qualitative analysis of cells. However, its straightforward applicability for extracellular vesicles (EVs) and mainly exosomes is hampered by several challenges, reflecting mostly the small size of these vesicles (exosomes: ~80-200 nm, microvesicles: ~200-1,000 nm), their polydispersity, and low refractive index. The current best and most widely used protocol for beads-free flow cytometry of exosomes uses ultracentrifugation (UC) coupled with floatation in sucrose gradient for their isolation, labeling with lipophilic dye PKH67 and antibodies, and an optimized version of commercial high-end cytometer for analysis. However, this approach requires an experienced flow cytometer operator capable of manual hardware adjustments and calibration of the cytometer. Here, we provide a novel and fast approach for quantification and characterization of both exosomes and microvesicles isolated from cell culture media as well as from more complex human samples (ascites of ovarian cancer patients) suitable for multiuser labs by using a flow cytometer especially designed for small particles, which can be used without adjustments prior to data acquisition. EVs can be fluorescently labeled with protein-(Carboxyfluoresceinsuccinimidyl ester, CFSE) and/or lipid- (FM) specific dyes, without the necessity of removing the unbound fluorescent dye by UC, which further facilitates and speeds up the characterization of microvesicles and exosomes using flow cytometry. In addition, double labeling with protein- and lipid-specific dyes enables separation of EVs from common contaminants of EV preparations, such as protein aggregates or micelles formed by unbound lipophilic styryl dyes, thus not leading to overestimation of EV numbers. Moreover, our protocol is compatible with antibody labeling using fluorescently conjugated primary antibodies. The presented methodology opens the possibility for routine quantification and characterization of EVs from various sources. Finally, it has the potential to bring a desired level of control into routine experiments and non-specialized labs, thanks to its simple bead-based standardization.

Can a weight loss of one pound a week be achieved with a 3500-kcal deficit? Commentary on a commonly accepted rule

Despite theoretical evidence that the model commonly referred to as the 3500-kcal rule grossly overestimates actual weight loss, widespread application of the 3500-kcal formula continues to appear in textbooks, on respected government- and health-related websites, and scientific research publications. Here we demonstrate the risk of applying the 3500-kcal rule even as a convenient estimate by comparing predicted against actual weight loss in seven weight loss experiments conducted in confinement under total supervision or objectively measured energy intake. We offer three newly developed, downloadable applications housed in Microsoft Excel and Java, which simulates a rigorously validated, dynamic model of weight change. The first two tools available at http://www.pbrc.edu/sswcp, provide a convenient alternative method for providing patients with projected weight loss/gain estimates in response to changes in dietary intake. The second tool, which can be downloaded from the URL http://www.pbrc.edu/mswcp, projects estimated weight loss simultaneously for multiple subjects. This tool was developed to inform weight change experimental design and analysis. While complex dynamic models may not be directly tractable, the newly developed tools offer the opportunity to deliver dynamic model predictions as a convenient and significantly more accurate alternative to the 3500-kcal rule.

Modified release terbutaline (SKP1052) for hypoglycaemia prevention: a proof-of-concept study in people with type 1 diabetes mellitus

AIMS

In this randomized, single blind, cross-over study 2.5 mg and 5 mg of the modified-release terbutaline formulation (SKP-1052) were compared with conventional immediate-release terbutaline (IRT, 5 mg) and placebo on overnight blood glucose (BG) and hypoglycaemia in 30 subjects with type 1 diabetes mellitus.

METHODS

Subjects received subcutaneous injections of insulin glargine (individualized doses) before dinner. SKP-1052, IRT or placebo was administered around 21:00 hours. BG and terbutaline concentrations were monitored overnight for 10 h post-dosing. Endpoints comprised of the nadir BG (BGn 0-10 h, primary endpoint), mean overnight BG (BGmean), morning BG (BGmorning) and hypoglycaemia rates as well as pharmacokinetic (PK) endpoints.

RESULTS

SKP-1052 delayed release of terbutaline by 2 h [PK-tmax (mean ± SD) 5.0 ± 2.1 h (2.5 mg) and 4.7 ± 1.7 h (5 mg) vs. 2.6 ± 1.3 h with IRT, p < 0.01, respectively]. Compared with placebo, no significant differences were observed for BGn 0-10 h across treatments, but both 5 mg formulations showed less hypoglycaemic events [10 (IRT), 16 (SKP-1052) vs. 33], higher BGmean (120, 114 and 95 mg/dl) and BGmorning (126, 126 and 101 mg/dl, all comparisons p < 0.05 vs. placebo). Numerically higher BG-levels between 3 and 8 h post-dosing were observed with 2.5 mg SKP-1052 vs. placebo.

CONCLUSIONS

Compared with IRT SKP-1052 delays release of terbutaline. 2.5 mg SKP-1052 led to numerically higher BG 3 to 8 h post-dose without fasting hyperglycaemia while 5 mg SKP-1052 resulted in fasting hyperglycaemia vs. placebo. Future studies will investigate optimized doses of SKP-1052 for nocturnal hypoglycaemia prevention.

N-cadherin, E-cadherin, ERCC1, and c-kit expression in small cell lung cancer (SCLC) and potential for new therapeutic targets

e22157

Background: Minimal advances have been made in the treatment of SCLC. Molecular markers may allow us to better stratify patients (pts) for new treatment options and drug combinations. The objective of our study was to determine the frequency and potential prognostic significance of N-cadherin (N-cad), E-cadherin (E-cad), ERCC1, and c-kit (CD117) expression in SCLC. Methods: Tissue from 132 pts with SCLC was retrospectively stained for N-cad, E-cad, ERCC1, and c-kit. Frequency of expression (% of tumor cells staining positive) was measured on a scale of 0–4 (freq 0=no expression (<1%), freq 1=1–10%, freq 2=11–35%, freq 3=36–70%, freq 4=71–100%). Charts were reviewed for stage, performance status, date of diagnosis/death, survival, and treatment (type, dates, response). The frequency of molecular markers was correlated with clinical data and overall survival. Results: Age range 42 to 97 years, 65 male:67 female, and 64 had limited and 68 had extensive stage. Of the 132 pts, 75% had tumors that expressed (frequency ≥ 1) N-cad, 58% E-cad, 70% ERCC1, and 55% c-kit. Comparing tumor marker expression with survival using either the Log-Rank Test or the Wilcoxon Test, there was no significant association for N-cad, E-cad, or ERCC1. However, tumors that expressed c-kit with frequency ≥ 3 had a trend toward superior survival compared with frequency < 3. Median survival for c-kit frequency ≥ 3 was 496 days compared to 312 days for frequency < 3 (p = 0.09, Log-Rank Test). Conclusions: In our retrospective study of 132 SCLC pts, we found that all 4 markers were expressed in greater than 50% of specimens, and that higher c-kit expression was associated with marginally significant increase in overall survival. Though previous experience with imatinib alone or with chemotherapy showed limited clinical activity in unselected SCLC pts, given preclinical synergy with cisplatin, it seems reasonable to consider combination therapy with cisplatin/etoposide and imatinib in pts selected for high c-kit expression.

[Table: see text]

No significant financial relationships to disclose.

Pharmacokinetics and safety of nelfinavir when used in combination with zidovudine and lamivudine in HIV-infected pregnant women: Pediatric AIDS Clinical Trials Group (PACTG) Protocol 353

BACKGROUND

Combination antiretroviral regimens including nelfinavir (NFV) are commonly used in pregnancy. We studied the safety, antiviral effect, and pharmacokinetics of NFV and its M8 metabolite with two dosing regimens in combination with zidovudine (ZDV) and lamivudine (3TC) in HIV-infected pregnant women.

METHOD

HIV-infected pregnant women between 14 and 34 weeks gestation received NFV (Cohort 1: 750 mg tid, n = 10; Cohort 2: 1250 mg bid, n = 23) with ZDV and 3TC. Serial blood sampling for NFV concentrations was performed antepartum (AP) and 6 weeks postpartum (PP). Maternal and cord blood samples were also obtained at delivery. NFV and M8 levels were determined by high-performance liquid chromatography. The pharmacokinetic (PK) target was an extrapolated NFV AUC0-24 > 30 mug . h/mL. Mothers were followed frequently for potential clinical and laboratory toxicity.

RESULTS

Overall, NFV in combination with ZDV and 3TC was well tolerated. The PK target was met in 3/8 AP and 5/7 PP in Cohort 1 and 17/21 AP and 16/17 PP in Cohort 2. When Cohort 2 NFV PK parameters AP and PP were compared, median Cmax (3.90 microg/mL vs. 5.01 microg/mL, p < .05) and AUC0-24 (56.6 vs. 86.8 microg . h/mL, p < .05) were increased PP and oral clearance (Cl/F; 44.2 vs. 28.8 L/h, p < .05) was decreased PP. The average M8/NFV ratio was increased PP compared to AP (0.085 vs. 0.29, p < .001). Placental transfer of NFV was low with a median cord blood:maternal plasma ratio at delivery of 0.05. Maternal mean CD4+ T cell counts increased significantly and plasma HIV-1 RNA levels decreased from entry to delivery and 6 to 12 weeks postpartum.

CONCLUSION

NFV used in combination with ZDV and 3TC was well tolerated in pregnant HIV-infected women and produced a significant improvement in HIV disease parameters. NFV drug exposure is inadequate in most pregnant women receiving 750 mg tid but is much improved with 1250 mg bid. NFV crosses the placenta poorly. The AP increase in NFV oral clearance and decrease in M8/NFV ratio suggest that CYP3A activity increases relative to CYP2C19 activity during pregnancy.

Identification of transcripts overexpressed during airway epithelium differentiation

Human airway epithelium, the defence at the forefront of protecting the respiratory tract, evacuates inhaled particles by a permanent beating of epithelial cell cilia. When deficient, this organelle causes primary ciliary dyskinesia, and, despite numerous studies, data regarding ciliated cell gene expression remain incomplete. The aim of the present study was to identify genes specifically expressed in human ciliated respiratory cells via transcriptional analysis. The transcriptome of dedifferentiated epithelial cells was subtracted from that of fully redifferentiated cells using complementary DNA representational difference analysis. In order to validate the results, gene overexpression in ciliated cells was confirmed by real-time PCR, and by comparing the present list of genes overexpressed in ciliated cells to lists obtained in previous studies. A total of 53 known and 12 unknown genes overexpressed in ciliated cells were identified. The majority (66%) of known genes had never previously been reported as being involved in ciliogenesis, and the unknown genes represent hypothetical novel transcript isoforms or new genes not yet reported in databases. Finally, several genes identified here were located in genomic regions involved in primary ciliary dyskinesia by linkage analysis. In conclusion, the present study revealed sequences of new cilia-related genes, new transcript isoforms and novel genes which should be further characterised to aid understanding of their function(s) and their probable disorder-related involvement.

Section 5: Decision Support, Knowledge Representation and Management: Free and Open Source Enabling Technologies for Patient-Centric, Guideline-Based Clinical Decision Support: A Survey

Guideline-based clinical decision support is an emerging paradigm to help reduce error, lower cost, and improve quality in evidence-based medicine. The free and open source (FOS) approach is a promising alternative for delivering cost-effective information technology (IT) solutions in health care. In this paper, we survey the current FOS enabling technologies for patient-centric, guideline-based care, and discuss the current trends and future directions of their role in clinical decision support.

We searched PubMed, major biomedical informatics websites, and the web in general for papers and links related to FOS health care IT systems. We also relied on our background and knowledge for specific subtopics. We focused on the functionalities of guideline modeling tools, and briefly examined the supporting technologies for terminology, data exchange and electronic health record (EHR) standards.

To effectively support patient-centric, guideline-based care, the computerized guidelines and protocols need to be integrated with existing clinical information systems or EHRs. Technologies that enable such integration should be accessible, interoperable, and scalable. A plethora of FOS tools and techniques for supporting different knowledge management and quality assurance tasks involved are available. Many challenges, however, remain in their implementation.

There are active and growing trends of deploying FOS enabling technologies for integrating clinical guidelines, protocols, and pathways into the main care processes. The continuing development and maturation of such technologies are likely to make increasingly significant contributions to patient-centric, guidelinebased clinical decision support.

Serum biomarker discovery for ovarian serous carcinoma using novel proteomic methods

16058

Background: Ovarian serous carcinoma (OSC) is the most common ovarian cancer sub-type and fourth leading cause of cancer-related deaths for women in the US. Unfortunately, more than two-thirds of women with ovarian cancer present at an advanced stage, when prognosis is poor. Developing methods to detect ovarian cancer at stage I, when it is 90% curable by surgery, or at stage II where survival is 70%, offers the best prospect for changing the clinical course of this dread malignancy. Methods: Serum specimens were collected both before and 3–6 weeks after tumor resection for patients with Stage I/ II high-grade serous carcinoma. None suffered recurrence within 6 months. We collected 98 ‘paired’ (pre- and post operative) serum specimens; including 41 benign paired specimens for comparison. A SELDI-TOF mass spectrometer was used to generate the serum proteomic profiles, optimized for the 2,000–40,000 m/z range. All data analyses were performed in a blinded manner using Bioconductor, an extension of the R-project statistical platform (v2.2.0). Raw spectra were processed as follows: baseline subtraction, spectra normalization, and differential peak detection. Aligned peaks were sorted into groups, based on tumor pathology and pre- vs. post-operative specimen type, and compared using a two tailed homoscedastic t-test. Results: The proteomes of pre- and post-operative serum from 10 patients with OSC were evaluated for significant changes in composition and compared with a set of 8 ‘normal’ specimens (i.e. patients undergoing major surgery for benign disease). We identified 18 serum components common to all OSC pre-op specimens that were extensively reduced or absent (p < 0.05) after tumor resection and 26 components capable of discerning pre-op OSC from pre-op normal specimens (p < 0.05). Most notable of these are components with m/z ratios of 2029.1, 2203.6, 6442.3, and 6851.9, based on level of significance (p < 0.001). Conclusions: These results validate the power of our ‘pre- vs. post- operative’ analysis strategy for the identification of novel serum biomarker candidates. Efforts are currently focused on expanding the scope of our specimen bank and identifying the putative biomarker candidates via mass spectrometry.

No significant financial relationships to disclose.

Changes in the chemical composition of water-extractable organic matter during composting: distribution between stable and labile organic matter pools

Aerobic decomposition and stabilization of organic matter during the composting of waste materials is primarily due to the biochemical transformation of water-soluble compounds in the liquid phase by the microbial biomass. For this reason water-soluble organic matter represents the most active fraction of compost, both biologically and chemically, and thus should directly reflect the biochemical alteration of organic matter. This work aims to elucidate the microbial-mediated processes responsible for the distribution of soluble organic matter between stable and labile pools with composting time. Accordingly, chemical analysis as well as UV absorption, and 1H and 13C-NMR spectroscopy of samples collected during the industrial composting of urban waste revealed microbial induced transformation of water-extractable organic matter over time. The chemical composition changed from labile, hydrophilic, plant-derived organic compounds in the beginning to predominately stable, hydrophobic moieties comprising lignin-derived phenols and microbially-derived carbohydrates at later stages of composting.

Free and open source enabling technologies for patient-centric, guideline-based clinical decision support: a survey

OBJECTIVES

Guideline-based clinical decision support is an emerging paradigm to help reduce error, lower cost, and improve quality in evidence-based medicine. The free and open source (FOS) approach is a promising alternative for delivering cost-effective information technology (IT) solutions in health care. In this paper, we survey the current FOS enabling technologies for patient-centric, guideline-based care, and discuss the current trends and future directions of their role in clinical decision support.

METHODS

We searched PubMed, major biomedical informatics websites, and the web in general for papers and links related to FOS health care IT systems. We also relied on our background and knowledge for specific subtopics. We focused on the functionalities of guideline modeling tools, and briefly examined the supporting technologies for terminology, data exchange and electronic health record (EHR) standards.

RESULTS

To effectively support patient-centric, guideline-based care, the computerized guidelines and protocols need to be integrated with existing clinical information systems or EHRs. Technologies that enable such integration should be accessible, interoperable, and scalable. A plethora of FOS tools and techniques for supporting different knowledge management and quality assurance tasks involved are available. Many challenges, however, remain in their implementation.

CONCLUSIONS

There are active and growing trends of deploying FOS enabling technologies for integrating clinical guidelines, protocols, and pathways into the main care processes. The continuing development and maturation of such technologies are likely to make increasingly significant contributions to patient-centric, guideline-based clinical decision support.

EGFR mutations (muts), IHC and FISH status, and chromosome 7 gene copy number combined with pAkt expression as potential predictors of survival in non-small cell lung cancer (NSCLC) patients (pts) treated with gefitinib (GEF)

7182

Background: EGFR and pAkt expression by immunohistochemistry (IHC), muts, and FISH status have been identified as possible molecular predictors for GEF efficacy in NSCLC (Cappuzzo, et. al, JNCI, 2005). The goal of this study was to independently evaluate these findings regarding survival (surv), and to assess the predictive value of mean chromosome 7 copy number/cell (C7). Methods: 150 consecutive Expanded Access Trial pts with >1 week GEF therapy were included for analysis. IHC (present vs not detected) was performed for 87 pts, and 58 pts were analyzed for muts by SSCP, mut-specific PCR, and sequencing. Tissue from 81 pts was evaluated for EGFR and C7 gene copy numbers by fluorescence in situ hybridization (FISH). Results: 150 pts (77 female, 73 male; median (md) age 67; 85 adenocarcinoma) received GEF; md follow-up was 5.8 months (mo). Overall response was 8% (2 CR, 10 PR); 56 pts had stable disease. Md Kaplan-Meier surv was 5.9 mo. IHC revealed that 47/87 pts (54%) had EGFR+, and 36/75 pts (48%) had pAkt + tumors. pAkt+ pts had significantly (sig) longer surv than pAkt− pts (11.4 vs 5.8 mo, p < .05). High polysomy was seen in 36/81 pts (44%) who were designated FISH+; 45 pts were FISH−. EGFR IHC and FISH positivity were not sig associated with surv. C7 was defined as low (<3.6, 63 pts) or high (≥3.6, 18 pts); md surv was 6.6 and 17.1 mo, respectively, p < .01. Muts were found in 17/58 tumors (29%). Md surv for pts with and without muts was 23.8 and 7.9 mo, respectively, p < .07. EGFR IHC− pAkt− pts (18 pts) had sig shorter surv than 57 pts with any pos value (4.7 vs 8.8 mo, p < .02). Double-positive pts had sig longer surv than pts with any neg value. Conclusions: These findings resemble but do not duplicate those reported by Cappuzzo, et al. Additionally, high C7, alone or combined with pAKT, may be an important predictor for GEF efficacy in NSCLC. Further studies of C7, a technically simple and reproducible FISH assay, are warranted.

[Table: see text]

[Table: see text]

Associations between chromosome 7 aneusomy and EGFR copy number with survival and response to gefitinib in NSCLC

7171

Background: EGFR, the presumed target of gefitinib and erlotinib, has been studied (expression, gene copy number, & mutations) for predicting response to these tyrosine kinase inhibitors (TKI), in non-small cell lung cancer (NSCLC). ’High polysomy’ and ’amplification’ of the EGFR gene, as defined by Cappuzzo et al. JNCI 97:643, using fluorescence in situ hybridization (FISH), showed significant association with objective response (Resp) and survival. We also measured EGFR and chromosome 7 (C7) copy numbers by FISH in 81 gefitinib-treated NSCLC patients (12 Resp). Using Cappuzzo’s FISH± parameter alone we saw similar trends but no statistical significance in the 81 patient group. Therefore we sought to optimize FISH parameters for these patients. Methods: FISH was performed (paraffin sections) using a 2-color probe set (Vysis LSI EGFR/CEP 7), median 80 cells per specimen. >50 parameters were derived from the data (e.g. mean EGFR/cell, C7/cell etc) and compared, using different threshold values, to Resp and survival. Results: The best single parameter associated with survival was the average C7/cell. Applying upper and lower thresholds of 3.6 and 2.0 C7/cell to delineate moderate from extreme ratios yielded median survival of 177 and 465 d, respectively (Kaplan-Meier, p < .002). A single threshold of 3.6, separating low from high, yielded survival of 201 and 522 d, respectively (p < .01). For these thresholds C7/cell was not associated with Resp, however, thresholds could be found for which both survival and Resp were significant. The best single parameter associated with Resp was average EGFR/cell. Of the 70 patients with EGFR/cell≤6.0, 63 (90%) did not respond while 5 of 11 patients (45%) with EGFR/cell >6.0 responded (p < .01). No EGFR/cell threshold could be found for which both survival and Resp were significant. Many 2-parameter combinations provided significant associations with both survival and Resp. Conclusions: Several FISH-derived parameters were significantly associated with either survival or Resp to gefitinib and a subset were associated with both. These parameters must be tested on independent data sets to determine their value in directing TKI therapy.

[Table: see text]

Hydralazine is a powerful inhibitor of peroxynitrite formation as a possible explanation for its beneficial effects on prognosis in patients with congestive heart failure

The hemodynamic and anti-ischemic effects of nitroglycerin (GTN) are rapidly blunted as a result of the development of nitrate tolerance. Hydralazine has been shown to prevent tolerance in experimental and clinical studies, all of which may be at least in part secondary to antioxidant properties of this compound. The antioxidant effects of hydralazine were tested in cell free systems, cultured smooth muscle cells, isolated mitochondria, and isolated vessels. Inhibitory effects on the formation of superoxide and/or peroxynitrite formation were tested using lucigenin and L-012 enhanced chemiluminescence as well as DHE-fluorescence. The peroxynitrite scavenging properties were also assessed by inhibition of nitration of phenol. Prevention of impairment of NO downstream signaling and GTN bioactivation was determined by measurement of P-VASP (surrogate parameter for the activity of the cGMP-dependent kinase-I, cGK-I) and mitochondrial aldehyde dehydrogenase (ALDH-2) activity. Hydralazine dose-dependently decreased the chemiluminescence signal induced by peroxynitrite from SIN-1 and by superoxide from HX/XO in a cell free system, by superoxide in smooth muscle cells and mitochondria acutely challenged with GTN. Moreover, hydralazine inhibited the peroxynitrite-mediated nitration of phenols as well as proteins in smooth muscle cells in a dose-dependent fashion. Finally, hydralazine normalized impaired cGK-I activity as well as impaired vascular ALDH-2 activity. Our results indicate that hydralazine is a highly potent radical scavenger. Thus, the combination with isosorbide dinitrate (ISDN) will favorably influence the nitroso-redox balance in the cardiovascular system in patients with congestive heart failure and may explain at least in part the improvement of prognosis in patients with chronic congestive heart failure.