Can we predict sputum eosinophilia from clinical assessment in patients referred to an adult asthma clinic?

BACKGROUND

There is overwhelming evidence that asthma guidelines aimed at reducing airway inflammation are superior to those based on clinical symptoms alone. This involves targeting eosinophilic inflammation with inhaled corticosteroids.

AIM

Because induced sputum is not readily available, our study set out to investigate whether the collective or singular use of routine asthma investigations can predict sputum eosinophilia.

METHODS

Eighty patients underwent skin prick testing, blood tests (IgE, full blood count), spirometry, exhaled fraction nitric oxide (FeNO), PD15 to hypertonic saline, and induced sputum testing at first assessment. A predictive model for sputum eosinophilia (defined as ≥3% eosinophils) was sought using routinely available tests.

RESULTS

Fifty-four subjects underwent both induced sputum and FeNO testing. Seventeen (30%) revealed eosinophilic inflammation, nine (16%) neutrophilic, four (7%) mixed granulocytic and 26 (46%) paucigranulocytic. Positive predictors for sputum eosinophilia included low forced expiratory volume in 1 s (FEV(1))% predicted, raised serum eosinophil, positive smoking history, Polynesian ethnicity and negative asthma family history. There was a non-statistically significant trend for FeNO predicting sputum eosinophilia. The best combination of predictors was low FEV(1)% predicted, raised serum eosinophil, positive smoking history and negative family history of asthma.

CONCLUSION

This study demonstrates that the serum eosinophil count and FEV(1) combined with aspects of a clinical history may provide a simple and practical alternative to assessment of airway (sputum) eosinophilia in the clinical setting. A full blood count can be performed at a substantially lesser cost and with greater accessibility than induced sputum. We feel the time has come for the clinical utility of the serum eosinophil count to be revisited.

Pregnancy intention and postpartum depression: secondary data analysis from a prospective cohort

OBJECTIVE

To assess the relationship between unintended pregnancy and postpartum depression.

DESIGN

Secondary analysis of data from a prospective pregnancy cohort.

SETTING

The study was performed at the University of North Carolina prenatal care clinics.

POPULATION/SAMPLE

Pregnant women enrolled for prenatal care at the University of North Carolina Hospital Center.

METHODS

Participants were questioned about pregnancy intention at 15-19 weeks of gestation, and classified as having an intended, mistimed or unwanted pregnancy. They were evaluated for postpartum depression at 3 and 12 months postpartum. Log binomial regression was used to assess the relationship between unintended pregnancy and depression, controlling for confounding by demographic factors and reproductive history.

MAIN OUTCOME MEASURES

Depression at 3 and 12 months postpartum, defined as Edinburgh Postpartum Depression Scale score >13.

RESULTS

Data were analysed for 688 women at 3 months and 550 women at 12 months. Depression was more likely in women with unintended pregnancies at both 3 months (risk ratio [RR] 2.1, 95% confidence interval [95% CI] 1.2-3.6) and 12 months (RR 3.6, 95% CI 1.8-7.1). Using multivariable analysis adjusting for confounding by age, poverty and education level, women with unintended pregnancies were twice as likely to have postpartum depression at 12 months (RR 2.0, 95% CI 0.96-4.0).

CONCLUSION

While many elements may contribute to postpartum depression, unintended pregnancy could also be a contributing factor. Women with unintended pregnancy may have an increased risk of depression up to 1 year postpartum.

Value of 3-D CT in classifying acetabular fractures during orthopedic residency training

The complex anatomy of the pelvis and acetabulum have historically made classification and interpretation of acetabular fractures difficult for orthopedic trainees. The addition of 3-dimensional (3-D) computed tomography (CT) scan has gained popularity in preoperative planning, identification, and education of acetabular fractures given their complexity. Therefore, the authors examined the value of 3-D CT compared with conventional radiography in classifying acetabular fractures at different levels of orthopedic training. Their hypothesis was that 3-D CT would improve correct identification of acetabular fractures compared with conventional radiography.The classic Letournel fracture pattern classification system was presented in quiz format to 57 orthopedic residents and 20 fellowship-trained orthopedic traumatologists. A case consisted of (1) plain radiographs and 2-dimensional axial CT scans or (2) 3-D CT scans. All levels of training showed significant improvement in classifying acetabular fractures with 3-D vs 2-D CT, with the greatest benefit from 3-D CT found in junior residents (postgraduate years 1-3).Three-dimensional CT scans can be an effective educational tool for understanding the complex spatial anatomy of the pelvis, learning acetabular fracture patterns, and correctly applying a widely accepted fracture classification system.

Abstract P5-06-10: ErbB Signaling Is Required for Activation of Phosphatidylinositol-3 Kinase and Transformation of Mammary Epithelial Cells by Polyomavirus Middle T Antigen

Summary

Polyomavirus middle T (PyVmT) transforms cells through phosphatidylinositol 3-kinase (PI3K). Overexpression of ErbB2/ErbB3 heterodimers, potent activators of PI3K, occurs in PyVmT-driven mouse mammary tumors, but without known cause and consequence. Inhibition of ErbB2 with lapatinib, or genetically engineered loss of ErbB3, decreased PI3K signaling and tumor growth in mice, suggesting ErbB2/ErbB3 is required by PyVmT. ErbB2/ErbB3 formed signaling complexes containing PyVmT, p85 and Src. EZN-3920, a novel high-affinity oligonucleotide targeting ErbB3 transcripts, impaired ErbB3 expression in vivo, decreased PI3K signaling, cell survival, and growth of tumors, and improved response to lapatinib. Therefore, PyVmT utilizes ErbB2/ErbB3 overexpression to drive PI3K signaling. Furthermore, the challenge of ErbB3 as a kinase-inactive therapeutic target can be overcome by targeting ErbB3 mRNA transcripts in vivo. Significance

Given the widespread use of, and knowledge gained from the MMTV-PyVmT transgenic mouse breast cancer model, understanding how PyVmT utilizes existing cell signaling programs is necessary to interpret how results impact our understanding/treatment of human breast cancers. We found that ErbB2/ErbB3 heterodimers were a necessary part of PyVmT signaling complexes involving Src and PI3K, and that PyVmT depends on ErbB3 in the breast epithelium for PI3K activity and tumor growth. Because ErbB3 harbors a weak/inactive tyrosine kinase, therapeutic anti-ErbB3 interventions present with challenges. Further, anti-ErbB3 antibodies that block ligand interaction with ErbB3 do not alter ligand-independent ErbB3 signaling. However. these challenges were overcome using high-affinity oligonucleotides targeting ErbB3 mRNA. Use of the oligonucleotide EZN-3920 effectively reduced ErbB3 expression, inhibited PyVmT tumor growth, and improved the response of tumors to lapatinib. These results support oligonucleotide knock-down of targets as potential therapeutic strategy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-06-10.

Transcriptional and Post-Translational Upregulation of HER3 (ErbB3) Counteracts Antitumor Effect of HER2 Tyrosine Kinase Inhibitors

We hypothesized that sustained inhibition of HER3 and its output to PI3K/Akt is required for the optimal antitumor effect of HER2 inhibitors. Therefore, we examined the temporal effect of the HER2 tyrosine kinase inhibitor (TKI) lapatinib (lap) on feedback upregulation of active HER3 in HER2-overexpressing breast cancer cells. A time course with lap-treated cells showed 3 to 5-fold upregulation of HER3 RNA and protein, beginning at 4 h and increasing through 48 h. P-Tyr immunoblot of HER3 immunoprecipitates revealed recovery of HER3 phosphorylation at and beyond 13 h of treatment. Site-specific antibodies revealed HER3 phosphorylation at Y1197 and Y1289, two of the six p85 binding sites in HER3. Recovery of P-HER3 correlated temporally with recovery of T308 P-Akt. The upregulation of HER3 RNA upon treatment with lap suggested that inhibition of active HER2 and PI3K/Akt derepresses the transcription factor FoxO3a. Putative FoxO3a binding sites were identified within the 5' flanking region upstream of the HER3 transcription start site. Transfection with FoxO3a siRNA reduced basal and lap-induced HER3 RNA levels 2 to 5-fold compared to control cells. Conversely, overexpression of FoxO3a increased HER3 RNA 2.5-fold, which could be further enhanced by lap treatment. In addition to these transcriptional mechanisms, the recovery of P-HER3 upon lap-induced inhibition of HER2 suggested engagement of another tyrosine kinase transactivating HER3 and/or that HER2 had been incompletely inhibited by the TKI. However, IGF-IR, Src, and MET TKIs did not inhibit the recovery of P-HER3. On the other hand, the addition of trastuzumab (tz) to lap-treated cells prevented recovery of P-HER3, suggesting that disruption of a ligand-independent HER2-HER3 interaction was involved in partial maintenance of HER3 phosphorylation.The upregulation of HER3 RNA and partial maintenance of P-HER3 and P-Akt suggested that combined inhibition of HER2 and HER3 will synergistically inhibit tumor cell viability. Transfection with HER3 siRNA sensitized HER2+ breast cancer cells to each lap and tz as assessed by Apo-BrdU (apoptosis) and 3D-Matrigel growth assays. Further, treatment with AMG-888, a HER3 monoclonal antibody (AMGEN-U3), sensitized cells to each lap and tz. Ongoing studies include the treatment of BT474 xenografts in athymic mice with lap ± AMG-888 using [18F]-FDG-PET as a non-invasive imaging biomarker to predict treatment outcome. Finally, we examined HER3 levels by immunohistochemistry in sections from tumor blocks of patients enrolled in a neoadjuvant trial where lap was given alone during the first 6 weeks of therapy. The percent and intensity of tumor cell staining was calculated as a histoscore (Human Pathol. 26:291, 1995). On week 2 of therapy, HER3 levels increased 135% above pre-therapy levels (n=8; p=0.03, Mann-Whitney). These data suggest that upon inhibition of the HER2 tyrosine kinase, HER2+ breast cancers 1) upregulate HER3 by transcriptional mechanisms and partially maintain HER3 function by post-translational mechanisms; 2) this compensatory phosphorylation of HER3 partially maintains PI3K/Akt; and 3) inhibition of HER3 sensitizes HER2-dependent breast cancer cells to HER2 inhibitors.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 63.

Characterization of formulated microbial products by denaturing gradient gel electrophoresis, total cellular fatty acid analysis, and DNA microarray analysis

Two commercial products, Biotize and Cycle, containing bacteria as an active ingredient were characterized for species identification and batch-to-batch variation by denaturing gradient gel electrophoresis (DGGE), total cellular fatty acid analysis (FAA), and a taxonomic DNA microarray. DGGE was useful at assessing the stability of consortia in different batches, and cluster analysis differentiated each batch even when only slight differences in species composition were observed. DGGE, FAA, and DNA microarray results indicated little batch-to-batch variation in Biotize and some batch variation in Cycle. The 3 methods agreed well with species identification in Biotize but generated conflicting results in the species composition of Cycle. This multi-method approach was useful in determining if the observed bacterial species present in the products matched the expected species composition.