Susan Davies

Expression Profiling of Purified Normal Human Luminal and Myoepithelial Breast Cells Identification of Novel Prognostic Markers for Breast Cancer

The normal duct-lobular system of the breast is lined by two epithelial cell types, inner luminal secretory cells and outer contractile myoepithelial cells. We have generated comprehensive expression profiles of the two normal cell types, using immunomagnetic cell separation and gene expression microarray analysis. The cell-type specificity was confirmed at the protein level by immunohistochemistry in normal breast tissue. New prognostic markers for survival were identified when the luminal- and myoepithelial-specific molecules were evaluated on breast tumor tissue microarrays. Nuclear expression of luminal epithelial marker galectin 3 correlated with a shorter overall survival in these patients, and the expression of SPARC (osteonectin), a myoepithelial marker, was an independent marker of poor prognosis in breast cancers as a whole. These data provide a framework for the interpretation of breast cancer molecular profiling experiments, the identification of potential new diagnostic markers, and development of novel indicators of prognosis.

Functions and analysis of the seminal fluid proteins of male Drosophila melanogaster fruit flies

The study of insect seminal fluid proteins provides a unique window upon adaptive evolution in action. The seminal fluid of Drosophila melanogaster contains over 80 proteins and peptides, which are transferred together with sperm by mating males. The functions of many of these substances are not yet known. However, those that have been characterized have marked effects on the reproductive success of males and females. For example, seminal fluid proteins and peptides can decrease female receptivity, can increase egg production and can increase sperm storage, and are necessary for sperm transfer and success in sperm competition. In this review we focus on the currently known functions of seminal fluid molecules and on new technologies and approaches that are enabling novel questions about their form and function to be addressed. We discuss how techniques for disrupting the production of seminal fluid proteins, such as homologous recombination and RNA interference, along with the use of microarrays and yeast two hybrid systems, should allow us to address ever more sophisticated questions about seminal fluid protein function. These and similar techniques promise to reveal the function of naturally-occurring variants of these proteins and hence the evolutionary significance of genetic variation for them.

Genetic alterations in 'normal' luminal and myoepithelial cells of the breast

Chromosomal loci exhibiting loss of heterozygosity (LOH) at high frequency in invasive breast cancer have been investigated in ‘normal’ breast tissue from patients with carcinoma and from reduction mammoplasty specimens. Duct‐lobular units dissected from paraffin‐embedded tissues and 485 ‘normal’ luminal and myoepithelial cell clones were studied. Overall, LOH was found in normal cells in 5/10 breast cancer cases and 1/3 reduction mammoplasty specimens. LOH was identified in normal cells adjacent to and distant from the tumour. In one case, all luminal and myoepithelial samples exhibited loss of the same allele on chromosome 13q. One case in which the patient had a germline truncating mutation in the BRCA1 gene exhibited LOH on 17q in 3/33 normal clones. One of these clones showed loss of wild‐type allele indicating gene inactivation. This sample also had LOH at markers on chromosomes 11p and 13q. One of 93 clones from three reduction mammoplasties showed allele loss at a locus on chromosome 13q. The identification of LOH in breast lobules suggests that they may be clonal. The demonstration of genetic alteration in luminal and myoepithelial cells provides evidence for the presence of a common stem cell for the two epithelial cell types. LOH has been demonstrated in normal tissues near and away from the carcinoma, suggesting that genetic alterations are likely to be more heterogeneous and widespread than is currently envisaged, and probably occur very early in breast development. Homozygous deletion of BRCA1 per se does not appear to provide clonal advantage. Copyright

Risk Algorithm Using Serial Biomarker Measurements Doubles the Number of Screen-Detected Cancers Compared With a Single-Threshold Rule in the United Kingdom Collaborative Trial of Ovarian Cancer Screening

Purpose Cancer screening strategies have commonly adopted single-biomarker thresholds to identify abnormality. We investigated the impact of serial biomarker change interpreted through a risk algorithm on cancer detection rates. Patients and Methods In the United Kingdom Collaborative Trial of Ovarian Cancer Screening, 46,237 women, age 50 years or older underwent incidence screening by using the multimodal strategy (MMS) in which annual serum cancer antigen 125 (CA-125) was interpreted with the risk of ovarian cancer algorithm (ROCA). Women were triaged by the ROCA: normal risk, returned to annual screening; intermediate risk, repeat CA-125; and elevated risk, repeat CA-125 and transvaginal ultrasound. Women with persistently increased risk were clinically evaluated. All participants were followed through national cancer and/or death registries. Performance characteristics of a single-threshold rule and the ROCA were compared by using receiver operating characteristic curves. Results After 296,911 women-years of annual incidence screening, 640 women underwent surgery. Of those, 133 had primary invasive epithelial ovarian or tubal cancers (iEOCs). In all, 22 interval iEOCs occurred within 1 year of screening, of which one was detected by ROCA but was managed conservatively after clinical assessment. The sensitivity and specificity of MMS for detection of iEOCs were 85.8% (95% CI, 79.3% to 90.9%) and 99.8% (95% CI, 99.8% to 99.8%), respectively, with 4.8 surgeries per iEOC. ROCA alone detected 87.1% (135 of 155) of the iEOCs. Using fixed CA-125 cutoffs at the last annual screen of more than 35, more than 30, and more than 22 U/mL would have identified 41.3% (64 of 155), 48.4% (75 of 155), and 66.5% (103 of 155), respectively. The area under the curve for ROCA (0.915) was significantly (P = .0027) higher than that for a single-threshold rule (0.869). Conclusion Screening by using ROCA doubled the number of screen-detected iEOCs compared with a fixed cutoff. In the context of cancer screening, reliance on predefined single-threshold rules may result in biomarkers of value being discarded.

Increased formation of S-nitrothiols and nitrotyrosine in cirrhotic rats during endotoxemia

Plasma S-nitrosothiols are believed to function as a circulating form of nitric oxide that affects both vascular function and platelet aggregation. However, the formation of circulating S-nitrosothiols in relation to acute and chronic disease is largely unknown. Plasma S-nitrosothiols were measured by chemiluminescence in rats with biliary cirrhosis or controls, and the effect of lipopolysaccharide (LPS) on their formation was determined. Plasma S-nitrosothiols were increased in rats with cirrhosis (206 +/- 59 nM) compared to controls (51 +/- 6 nM, p <.001). Two hours following injection of LPS (0.5 mg/kg) plasma S-nitrosothiols increased to 108 +/- 23 nM in controls (p <.01) and to 1335 +/- 423 nM in cirrhotic rats (p <.001). The plasma clearance and half-life of S-nitrosoalbumin, the predominant circulating S-nitrosothiol, were similar in control and cirrhotic rats, confirming that the increased plasma concentrations were due to increased synthesis. Because reactive nitrogen species, such as peroxynitrite, may cause the formation of S-nitrosothiols in vivo, we determined the levels of nitrotyrosine by gas chromatography/mass spectrometry as an index for these nitrating and nitrosating radicals. Hepatic nitrotyrosine levels were increased at 7.0 +/- 1.2 ng/mg in cirrhotic rats compared to controls (2.0 +/- 0.2 ng/mg, p <.01). Hepatic nitrotyrosine levels increased by 2.3-fold and 1.5-fold in control and cirrhotic rats, respectively, at 2 h following injection of LPS (p <.01). Strong positive staining for nitrotyrosine was shown by immunohistochemistry in all the livers of the rats with cirrhosis. We conclude that there is increased formation of S-nitrosothiols and nitrotyrosine in biliary cirrhosis, and this is markedly upregulated during endotoxemia.

Supporting quality improvement in care homes for older people: the contribution of primary care nurses.

AIMS This paper discusses how health and social care can work together collaboratively to improve the quality of care for older people resident in care homes, using Essence of Care benchmarking as an example. BACKGROUND There is an increasing interest in how care is provided in care homes, including its impact on quality-of-life and end-of-life care. Care standards and government policy have emphasized the need for primary care to work more closely with care home staff. EVALUATION The available evidence on older peoples health care needs, and how primary health care and nursing work in care homes was evaluated. Case studies and descriptive reports on Essence of Care benchmarking were also used to identify the facilitators and barriers to using it as a means to improve the quality of care for older people in care homes. KEY ISSUES The key issues relate to the differences in the working cultures of health and social care, and the complex health care needs of older people living in care homes that do not have onsite nursing support. CONCLUSIONS Structured tools such as benchmarking can potentially be used to improve the quality of care for older people in care homes, but care home staff need adequate support to adapt this approach to their working environment. IMPLICATIONS FOR NURSING MANAGEMENT Primary care nurses need to be more proactive in the way that they work with older people in care homes. Structured tools such as benchmarking can help them to recognize the range and complexity of residents health needs, and work with care home staff in ways that acknowledge their expertise and improve the overall care of older people in these settings.