Remote capillary blood collection for HbA1c measurement during the COVID-19 pandemic: A laboratory and patient perspective.

AIMS: The purpose of this study was to assess the clinical performance and user acceptance of capillary blood samples prepared remotely using the MiniCollect® capillary blood collection device as an alternative to blood collection by venepuncture for glycated haemoglobin (HbA1c ) analysis. METHODS: Following written informed consent, a cross-sectional study was conducted in individuals aged ≥18 years with any type of diabetes who routinely self-monitor their blood glucose. Eligible participants recruited whilst attending their routine clinical appointments were required to provide a venous blood sample, prepare a capillary blood sample at home (remotely) and complete a bespoke questionnaire. HbA1c in whole blood collected in ethylenediaminetetraacetic acid was determined by capillary electrophoresis on the Sebia Capillary's 3 Tera analyser following standard operating procedure. RESULTS: HbA1c results from both venous and capillary collection demonstrated good agreement. Passing-Bablok regression: y = 0 + 1x (p = 0.18), Spearman correlation r = 0.986, p < 0.0001. The Bland-Altman difference plot provided a mean difference of 0.3 mmol/mol (2.2%). Over half of the participants found the MiniCollect device easy to use. The majority of participants were in favour of the remote capillary blood collection service and would use it if routinely available. CONCLUSION: The home collection of capillary blood for HbA1c determination is a valuable and convenient alternative to standard venous blood collection as it provides an opportunity to support routine HbA1c monitoring, whilst mitigating the transmission of SARS-CoV-2. This service would additionally allow individuals to attend clinic visits with a HbA1c value, ensuring optimal continuance of patient care for individuals with diabetes.

Suboptimal management of hypernatraemia in acute medical admissions.

BACKGROUND: Hypernatraemia arises commonly in acute general medical admissions. Affected patients have a guarded prognosis with high rates of morbidity and mortality. Age-related physiology and physical/cognitive barriers to accessing water predispose older patients to developing hypernatraemia. This study sought to perform a descriptive retrospective review of hypernatraemic patients admitted under acute general medicine teams. METHODS: A retrospective cross-sectional study of a sample of acute medical in-patients with serum[sodium]>145 mmol/L was conducted. Patients were exclusively older(>69 years) and admitted from Nursing homes (NH)(41%) and non-NH pathways(59%). A comparison of management of NH /non-NH patients including clinical presentation, comorbidities, laboratory values, [sodium] monitoring, intravenous fluid regimes and patient outcomes was performed. RESULTS: In total, 102 consecutive patients (males, n=69(67.6%)) were included. Dementia and reduced mobility were more common in NH residents and admission serum [Sodium] higher (148 vs 142 mmol/L/p=0.003). Monitoring was inadequate: no routine bloods within the first 12h in >80% of patients in both groups. No patient had calculated free water deficit documented. More NH patients received correct fluid management (60% vs 33%/p%0.015). Incorrect fluid regimes occurred in both groups (38% vs 58%/p=0.070). Length of stay in discharged patients was lower in NH, (8(4-20) vs 20.5(9.8-49.3 days)/p=0.003). Time to death for NH residents was shorter (9(5.5-11.5) vs 16 (10.25-23.5) days/p=0.011). CONCLUSION: This study highlights suboptimal management of hypernatraemia. Implementation of hypernatraemia guidelines for general medical older inpatients are clearly required with mechanisms to confirm adherence. Health care workers require further education on diagnostic challenges of dehydration in older people and the importance of maintaining adequate hydration.

Burden of chronic kidney disease and rapid decline in renal function among adults attending a hospital-based diabetes center in Northern Europe.

INTRODUCTION: This study aimed to determine the prevalence of diabetic kidney disease (DKD) and rapid renal function decline and to identify indices associated with this decline among adults attending a diabetes center in Northern Europe. RESEARCH DESIGN AND METHODS: This is a retrospective cohort study of 4606 patients who attended a diabetes center in Ireland between June 2012 and December 2016. Definition/staging of chronic kidney disease used the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 classification based on data from the most recently attended appointment. Relevant longitudinal trends and variabilities were derived from serial records prior to index visit. Rapid renal function decline was defined based on per cent and absolute rates of estimated glomerular filtration rate (eGFR) change. Multiple linear regression was used to explore the relationships between explanatory variables and per cent eGFR change. RESULTS: 42.0% (total), 23.4% (type 1 diabetes), 47.9% (type 2 diabetes) and 32.6% (other diabetes) had DKD. Rapid decline based on per cent change was more frequent in type 2 than in type 1 diabetes (32.8% vs 14.0%, p<0.001). Indices independently associated with rapid eGFR decline included older age, greater number of antihypertensives, higher log-normalized urine albumin to creatinine ratio (LNuACR), serum alkaline phosphatase, thyroid stimulating hormone, variability in systolic blood pressure and variability in LNuACR, lower glycated hemoglobin, high-density lipoprotein cholesterol and diastolic blood pressure, and lack of ACE inhibitor/angiotensin receptor blocker prescription. CONCLUSIONS: DKD (using the KDIGO 2012 classification) and rapid eGFR decline were highly prevalent among adults attending a hospital-based diabetes clinic in a predominantly Caucasian Northern European country. The burden was greater for adults with type 2 diabetes. Expected as well as potentially novel clinical predictors were identified.

Vitamin D Status of Adults in the Community, in Outpatient Clinics, in Hospital, and in Nursing Homes in the West of Ireland.

BACKGROUND: Approximately 1 billion people worldwide have Vitamin D deficiency. The aim of this study was to compare Vitamin D status and serum 25-hydroxyvitamin D (25(OH)D) concentrations among adults sampled in the community, in outpatient clinics, as hospital inpatients and in nursing homes in the West of Ireland. The secondary aim was to determine the associations between length of hospital stay (inpatients) at the time of serum 25(OH)D sampling and Vitamin D status. METHODS: A cross-sectional study was carried out. Patients who had serum 25(OH)D analysis carried out in Galway University Hospitals (January 2011-December 2015) were identified following interrogation of the electronic laboratory data system. Baseline demographics, location, and date of sample collection were recorded. Vitamin D deficiency was defined as a serum 25(OH)D concentration <25 nmol/L. RESULTS: In total, 24,302 patient samples were eligible for inclusion: community 15,319; outpatient clinics 6,371; inpatients 2,339; and nursing home residents 273. Vitamin D deficiency was more common in nursing home residents than inpatients, or those sampled in outpatient clinics or in the community (42% vs 37% vs 17% vs 13%; p < .001). Inpatients sampled further into their hospital stay (≥3 days) had greater Vitamin D deficiency than inpatients sampled on 0-2 days (p = .007). Season (p < .001), sex (p < .001), and age (p < .001) were associated with 25(OH)D concentrations. Vitamin D deficiency was more common in Winter/Spring, in males, and in those aged ≥80 years. CONCLUSIONS: Nursing home residents and inpatients are at the highest risk for Vitamin D deficiency. Season, sex, age, and day of hospital stay on which serum 25(OH)D concentrations were sampled were associated with Vitamin D status.

Higher risk of vitamin D insufficiency/deficiency for rural than urban dwellers.

There are many risk factors for Vitamin D deficiency. This study aimed to compare the Vitamin D status and serum 25(OH)D concentrations of adults living in an urban area to adults living in a rural area in the West of Ireland (latitude 53.27° North). A cross-sectional retrospective analysis of clinical records was performed. Following interrogation of the electronic laboratory information system, individuals who had serum 25(OH)D concentrations measured at Galway University Hospitals between January 2011 and December 2015 were identified. Clinical demographics, setting and date of sampling were recorded. In total, 17,590 patients (urban n = 4,824; rural n = 12,766) were eligible for inclusion. Serum 25(OH)D concentrations were lower among rural compared to urban dwellers irrespective of season (spring p < 0.001, summer p = 0.009, autumn p = 0.002, winter p < 0.001). There was a significant difference in Vitamin D status between urban and rural dwellers in three of the four seasons: spring- deficiency: 16%-v-23%, insufficiency: 39%-v-43%, sufficiency: 45%-v-35% (p < 0.001); autumn- deficiency: 11%-v-10%, insufficiency: 30%-v-35%, sufficiency: 59%-v-56% (p = 0.01); winter- deficiency: 23%-v-25%, insufficiency: 35%-v-42%, sufficiency: 41%-v-33% (p < 0.001). Serum 25(OH)D concentrations were higher and the prevalence of deficiency lower in urban/rural females compared to urban/rural males (p < 0.001). Serum 25(OH)D concentrations increased sequentially from the 18-39 year age group to the 60-69 year age group in both urban (p < 0.001) and rural (p < 0.001) dwellers and then decreased progressively as age increased to ≥90 years. The odds of Vitamin D deficiency increased with age, lower daily sunshine hours, male gender, rural address and season.

Plasma dephosphorylated-uncarboxylated Matrix Gla-Protein (dp-ucMGP): reference intervals in Caucasian adults and diabetic kidney disease biomarker potential.

Recent studies suggest a possible association between dephosphorylated-uncarboxylated MGP (dp-ucMGP) and glomerular filtration rate (GFR). This study aimed to establish normative data in an adult Caucasian population and to explore the potential utility of dp-ucMGP in patients with diabetes mellitus (DM) with and without diabetic kidney disease (DKD). Healthy volunteers (HVs) (cross-sectional study) and participants with DM (prospective cohort study) were recruited. Plasma dp-ucMGP was measured using the IDS®-iSYS Ina Ktif (dp-ucMGP) assay. Of the HVs recruited (n = 208), 67(32.2%) were excluded leaving a reference population of 141(67.8%) metabolically healthy participants with normal kidney function. Plasma dp-ucMGP RIs were <300-532 pmol/L. There were 100 eligible participants with DKD and 92 with DM without DKD. For the identification of participants with DKD, the area under the receiver operating characteristic curve (AUC) for dp-ucMGP was 0.842 (95%CI:0.799-0.880; p < 0.001). Plasma dp-ucMGP demonstrated similar ability to urine albumin:creatinine ratio (uACR) to detect participants with DM and renal function decline. Among patients with DM, there was a negative correlation between natural log (LN) dp-ucMGP and eGFR (r = -0.7041; p < 0.001) and rate of change in renal function [%change (r = -0.4509; p < 0.001)] and a positive correlation between LN dp-ucMGP and LN uACR (r = 0.3392; p < 0.001). These results suggest the potential for plasma dp-ucMGP with well-defined RIs to identify adults at high risk for vascular disease in the context of progressive DKD.

Defining reference intervals for a serum growth differentiation factor-15 (GDF-15) assay in a Caucasian population and its potential utility in diabetic kidney disease (DKD).

BACKGROUND: Growth differentiation factor-15 (GDF-15), a stress responsive cytokine, is a promising biomarker of renal functional decline in diabetic kidney disease (DKD). This study aimed primarily to establish normative data and secondarily to evaluate the potential utility of GDF-15 in DKD using Roche Diagnostics electrochemiluminescence immunoassay (ECLIA) in an Irish Caucasian population. METHODS: Following informed consent, 188 healthy volunteers and 128 participants with diabetes (72 with and 56 without DKD) were recruited to a cross-sectional study. Baseline demographics, anthropometric measurements and laboratory measurements were recorded. Blood for GDF-15 measurement was collected into plain specimen tubes kept at room temperature and processed (centrifugation, separation of serum, freezing at -80 °C) within 1 h of phlebotomy pending batch analyses. Reference intervals were determined using the 2.5th and 97.5th percentiles for serum GDF-15 concentration. RESULTS: Of 188 healthy participants, 63 failed to meet study inclusion criteria. The reference interval for serum GDF-15 was 399 ng/L (90% confidence interval [CI]: 399-399) - 1335 ng/L (90% CI: 1152-1445). Receiver operator characteristics (ROC) curve analysis for DKD determined the area under the ROC curve to be 0.931 (95% CI: 0.893-0.959; p<0.001). The optimum GDF-15 cutoff for predicting DKD was >1136 ng/L providing a diagnostic sensitivity and specificity of 94.4% and 79%, respectively, and positive likelihood ratio of 4.5:1 (95% CI: 3.4-6.0). CONCLUSIONS: The reference interval for serum GDF-15 in a healthy Irish Caucasian population using Roche Diagnostics ECLIA was established and a preliminary determination of the potential of GDF-15 as a screening test for DKD was made. Further prospective validation with a larger DKD cohort will be required before the cutoff presented here is recommended for clinical use.

A cross-sectional study of the effects of ß-blocker therapy on the interpretation of the aldosterone/renin ratio: can dosing regimen predict effect?

CONTEXT AND AIM: Aldosterone/renin ratio (ARR) is used as the primary screening tool for primary aldosteronism. Its interpretation is often challenging because of the interference of antihypertensive medication. ß-blocker therapy suppresses renin production by inhibiting ß-adrenergic receptors in the juxtaglomerular apparatus of the kidney and consequently aldosterone secretion (to a lesser extent). Therefore, ß-blocker therapy has the potential to elevate the ARR. The aim of this study was to investigate whether or not the effect of ß-blocker therapy on the ARR could be predicted from the dosing regimen. METHODS: A prospective cross-sectional study was conducted. Participants were stratified into one of four groups (control/low/medium/high) based on the quantity of ß-blocker prescribed. ARR was calculated from renin/aldosterone, measured using two assay systems. RESULTS: Eighty-nine volunteers were recruited to our study. In the control group, zero patients had a positive ARR using plasma renin activity (PRA)/direct renin concentration (DRC). In the low, medium, and high-dose ß-blocker groups between 8-25% of patients demonstrated screen positive ARR results for primary aldosteronism using DRC and PRA. DRC was significantly lower in patients in the medium/high-dose groups and PRA significantly lower in the low/medium/high-dose groups compared with controls. ARR using DRC was significantly higher in the medium/high-dose groups and ARR using PRA was significantly higher in the low/medium/high-dose groups compared with controls. CONCLUSION: Our study suggests that ß-blocker therapy is associated with an increased risk of positive ARR screens for primary aldosteronism irrespective of the dose of ß-blocker prescribed, in patients in whom it is clinically reasonable to expect that primary aldosteronism may be present.

MicroRNA-10a is reduced in breast cancer and regulated in part through retinoic acid.

BACKGROUND: MicroRNAs (miRNAs) are short non-coding RNA molecules that play a critical role in mRNA cleavage and translational repression, and are known to be altered in many diseases including breast cancer. MicroRNA-10a (miR-10a) has been shown to be deregulated in various cancer types. The aim of this study was to investigate miR-10a expression in breast cancer and to further delineate the role of retinoids and thyroxine in regulation of miR-10a. METHODS: Following informed patient consent and ethical approval, tissue samples were obtained during surgery. miR-10a was quantified in malignant (n = 103), normal (n = 30) and fibroadenoma (n = 35) tissues by RQ-PCR. Gene expression of Retinoic Acid Receptor beta (RARß) and Thyroid Hormone receptor alpha (THRα) was also quantified in the same patient samples (n = 168). The in vitro effects of all-trans Retinoic acid (ATRA) and L-Thyroxine (T4) both individually and in combination, on miR-10a expression was investigated in breast cancer cell lines, T47D and SK-BR-3. RESULTS: The level of miR-10a expression was significantly decreased in tissues harvested from breast cancer patients (Mean (SEM) 2.1(0.07)) Log10 Relative Quantity (RQ)) compared to both normal (3.0(0.16) Log10 RQ, p < 0.001) and benign tissues (2.6(0.17) Log10 RQ, p < 0.05). The levels of both RARß and THRα gene expression were also found to be decreased in breast cancer patients compared to controls (p < 0.001). A significant positive correlation was determined between miR-10a and RARß (r = 0.31, p < 0.001) and also with THRα (r = 0.32, p < 0.001). In vitro stimulation assays revealed miR-10a expression was increased in both T47D and SK-BR-3 cells following addition of ATRA (2 fold (0.7)). While T4 alone did not stimulate miR-10a expression, the combination of T4 and ATRA was found to have a positive synergistic effect. CONCLUSION: The data presented supports a potential tumour suppressor role for miR-10a in breast cancer, and highlights retinoic acid as a positive regulator of the microRNA.

A germline mutation in the BRCA1 3'UTR predicts Stage IV breast cancer.

BACKGROUND: A germline, variant in the BRCA1 3'UTR (rs8176318) was previously shown to predict breast and ovarian cancer risk in women from high-risk families, as well as increased risk of triple negative breast cancer. Here, we tested the hypothesis that this variant predicts tumor biology, like other 3'UTR mutations in cancer. METHODS: The impact of the BRCA1-3'UTR-variant on BRCA1 gene expression, and altered response to external stimuli was tested in vitro using a luciferase reporter assay. Gene expression was further tested in vivo by immunoflourescence staining on breast tumor tissue, comparing triple negative patient samples with the variant (TG or TT) or non-variant (GG) BRCA1 3'UTR. To determine the significance of the variant on clinically relevant endpoints, a comprehensive collection of West-Irish breast cancer patients were tested for the variant. Finally, an association of the variant with breast screening clinical phenotypes was evaluated using a cohort of women from the High Risk Breast Program at the University of Vermont. RESULTS: Luciferase reporters with the BRCA1-3'UTR-variant (T allele) displayed significantly lower gene expression, as well as altered response to external hormonal stimuli, compared to the non-variant 3'UTR (G allele) in breast cancer cell lines. This was confirmed clinically by the finding of reduced BRCA1 gene expression in triple negative samples from patients carrying the homozygous TT variant, compared to non-variant patients. The BRCA1-3'UTR-variant (TG or TT) also associated with a modest increased risk for developing breast cancer in the West-Irish cohort (OR=1.4, 95% CI 1.1-1.8, p=0.033). More importantly, patients with the BRCA1-3'UTR-variant had a 4-fold increased risk of presenting with Stage IV disease (p=0.018, OR=3.37, 95% CI 1.3-11.0). Supporting that this finding is due to tumor biology, and not difficulty screening, obese women with the BRCA1-3'UTR-variant had significantly less dense breasts (p=0.0398) in the Vermont cohort. CONCLUSION: A variant in the 3'UTR of BRCA1 is functional, leading to decreased BRCA1 expression, modest increased breast cancer risk, and most importantly, presentation with stage IV breast cancer, likely due to aggressive tumor biology.

Impact of tumour epithelial subtype on circulating microRNAs in breast cancer patients.

While a range of miRNAs have been shown to be dysregulated in the circulation of patients with breast cancer, little is known about the relationship between circulating levels and tumour characteristics. The aim of this study was to analyse alterations in circulating miRNA expression during tumour progression in a murine model of breast cancer, and to detemine the clinical relevance of identified miRNAs at both tissue and circulating level in patient samples. Athymic nude mice received a subcutaneous or mammary fat pad injection of MDA-MB-231 cells. Blood sampling was performed at weeks 1, 3 and 6 following tumour induction, and microRNA extracted. MicroRNA microArray analysis was performed comparing samples harvested at week 1 to those collected at week 6 from the same animals. Significantly altered miRNAs were validated across all murine samples by RQ-PCR (n = 45). Three miRNAs of interest were then quantified in the circulation(n = 166) and tissue (n = 100) of breast cancer patients and healthy control individuals. MicroArray-based analysis of murine blood samples revealed levels of 77 circulating microRNAs to be changed during disease progression, with 44 demonstrating changes >2-fold. Validation across all samples revealed miR-138 to be significantly elevated in the circulation of animals during disease development, with miR-191 and miR-106a levels significantly decreased. Analysis of patient tissue and blood samples revealed miR-138 to be significantly up-regulated in the circulation of patients with breast cancer, with no change observed in the tissue setting. While not significantly changed overall in breast cancer patients compared to controls, circulating miR-106a and miR-191 were significantly decreased in patients with basal breast cancer. In tissue, both miRNAs were significantly elevated in breast cancer compared to normal breast tissue. The data demonstrates an impact of tumour epithelial subtype on circulating levels of miRNAs, and highlights divergent miRNA profiles between tissue and blood samples from breast cancer patients.

Identification and validation of oncologic miRNA biomarkers for luminal A-like breast cancer.

INTRODUCTION: Breast cancer is a common disease with distinct tumor subtypes phenotypically characterized by ER and HER2/neu receptor status. MiRNAs play regulatory roles in tumor initiation and progression, and altered miRNA expression has been demonstrated in a variety of cancer states presenting the potential for exploitation as cancer biomarkers. Blood provides an excellent medium for biomarker discovery. This study investigated systemic miRNAs differentially expressed in Luminal A-like (ER+PR+HER2/neu-) breast cancer and their effectiveness as oncologic biomarkers in the clinical setting. METHODS: Blood samples were prospectively collected from patients with Luminal A-like breast cancer (n = 54) and controls (n = 56). RNA was extracted, reverse transcribed and subjected to microarray analysis (n = 10 Luminal A-like; n = 10 Control). Differentially expressed miRNAs were identified by artificial neural network (ANN) data-mining algorithms. Expression of specific miRNAs was validated by RQ-PCR (n = 44 Luminal A; n = 46 Control) and potential relationships between circulating miRNA levels and clinicopathological features of breast cancer were investigated. RESULTS: Microarray analysis identified 76 differentially expressed miRNAs. ANN revealed 10 miRNAs for further analysis (miR-19b, miR-29a, miR-93, miR-181a, miR-182, miR-223, miR-301a, miR-423-5p, miR-486-5 and miR-652). The biomarker potential of 4 miRNAs (miR-29a, miR-181a, miR-223 and miR-652) was confirmed by RQ-PCR, with significantly reduced expression in blood of women with Luminal A-like breast tumors compared to healthy controls (p = 0.001, 0.004, 0.009 and 0.004 respectively). Binary logistic regression confirmed that combination of 3 of these miRNAs (miR-29a, miR-181a and miR-652) could reliably differentiate between cancers and controls with an AUC of 0.80. CONCLUSION: This study provides insight into the underlying molecular portrait of Luminal A-like breast cancer subtype. From an initial 76 miRNAs, 4 were validated with altered expression in the blood of women with Luminal A-like breast cancer. The expression profiles of these 3 miRNAs, in combination with mammography, has potential to facilitate accurate subtype-specific breast tumor detection.

Surgeon and breast unit volume-outcome relationships in breast cancer surgery and treatment.

OBJECTIVES: To determine whether surgeon case volume and Unit case volume affected specific recognized key performance indicators (KPIs) of breast cancer surgical management. BACKGROUND: An increasing body of evidence suggests that a higher standard of cancer care, demonstrated by improved outcomes, is provided in high-volume units or by high-volume surgeons. The volume-outcome relationship pertaining to screen-detected breast cancers has yet to be thoroughly established and remains a pertinent issue in view of the debate surrounding breast cancer screening. METHODS: The study population comprised all women with a new screen diagnosed breast cancer between 2004-2005 and 2009-2010. Surgeons' mean annual patient volumes were calculated and grouped as very low (<5), low (5-15), medium (16-49), or high volume (>50). The effect of breast screening unit volume was also evaluated. Statistical analyses were performed using Minitab V16.0 software (State College, PA) and R V2.13.0. RESULTS: There were 81,416 patients aged 61 (±6.8) years treated by 682 surgeons across 82 units. There were 209 very low-, 126 low-, 295 medium-, and 51 high-volume surgeons. The proportion of patients managed by very low-, low-, medium-, and high-volume surgeons was 1.2%, 6.9%, 65.5%, and 25.7%, respectively. Patients managed by high-volume surgeons were more likely to have breast-conserving surgery (BCS) than those managed by low-volume surgeons (P < 0.001). There was a higher proportion of sentinel lymph node biopsies (SLNB) performed by high-volume surgeons in invasive cancers (P = 0.005). High-volume units performed more BCS and SLNB than low-volume units (P < 0.001 and P < 0.001, respectively). CONCLUSIONS: Even in a setting with established quality control measures (KPIs) surgeon and unit volume have potent influences on initial patient management and treatment.

Ultrasound investigation of sacral dimples and other stigmata of spinal dysraphism.

OBJECTIVE: To assess whether there was any relationship between the number of clinical markers for spinal dysraphism and its presence on ultrasound and whether there was any relationship between the presence of an isolated sacral dimple and the presence of spinal dysraphism. Outcomes and further imaging were also examined. METHODS: All patients who underwent spinal ultrasound (SUS) in University Hospital Galway (UHG) over a 5-year period (2006-2011) were identified. Patients were excluded based on age (>14 years old excluded) and indication for imaging (only patients being investigated for suspected spinal dysraphism were included). Indications for imaging, ultrasound results and information on further imaging were accessed from the computerised radiology software in UHG. Statistical analysis was performed using SPSS-18. RESULTS: Data were analysed for 216 patients. A single clinical indication was recorded for 174 ultrasound requests, ≥2 indications for 42 requests. Nineteen of 216 (8.8%) ultrasound images were abnormal, 7 having spinal dysraphism. Multiple clinical indications were 6 times more likely to have dysraphism than those imaged on the basis of a single marker (OR 6.0, 95% CI 1.289 to 27.922, p=0.022), and there was no significant correlation between the presence of a sacral dimple and the presence of dysraphism (95% CI 0.71 to 6.622, p=0.722). CONCLUSIONS: SUS performed on the basis of multiple clinical indications is six times more likely to detect spinal dysraphism than imaging performed for isolated abnormalities or risk factors. Sacral dimple is a poor marker for occult spinal pathology.

miR-379 regulates cyclin B1 expression and is decreased in breast cancer.

MicroRNAs are small non-coding RNA molecules that control gene expression post-transcriptionally, and are known to be altered in many diseases including breast cancer. The aim of this study was to determine the relevance of miR-379 in breast cancer. miR-379 expression was quantified in clinical samples including tissues from breast cancer patients (n=103), healthy controls (n=30) and patients with benign breast disease (n=35). The level of miR-379 and its putative target Cyclin B1 were investigated on all breast tissue specimens by RQ-PCR. Potential relationships with gene expression and patient clinicopathological details were also determined. The effect of miR-379 on Cyclin B1 protein expression and function was investigated using western blot, immunohistochemistry and proliferation assays respectively. Finally, the levels of circulating miR-379 were determined in whole blood from patients with breast cancer (n=40) and healthy controls (n=34). The level of miR-379 expression was significantly decreased in breast cancer (Mean(SEM) 1.9 (0.09) Log10 Relative Quantity (RQ)) compared to normal breast tissues (2.6 (0.16) Log10 RQ, p<0.01). miR-379 was also found to decrease significantly with increasing tumour stage. A significant negative correlation was determined between miR-379 and Cyclin B1 (r=-0.31, p<0.001). Functional assays revealed reduced proliferation (p<0.05) and decreased Cyclin B1 protein levels following transfection of breast cancer cells with miR-379. Circulating miR-379 was not significantly dysregulated in patients with breast cancer compared to healthy controls (p=0.42). This data presents miR-379 as a novel regulator of Cyclin B1 expression, with significant loss of the miRNA observed in breast tumours.

Prediction of Oncotype DX and TAILORx risk categories using histopathological and immunohistochemical markers by classification and regression tree (CART) analysis.

Oncotype DX is an RT-PCR assay used to predict which patients with ER-positive node-negative (NN) disease will benefit from chemotherapy. Each patient is stratified into a risk category based on a recurrence score (RS) and the TAILORx trial is determining the benefit of chemotherapy for patients with mid-range RSs. We tested if Oncotype DX and TAILORx risk categories could be predicted by standard pathological features and protein markers corresponding to 10 genes in the assay (ER, PR, Ki67, HER2, BCL2, CD68, Aurora A kinase, survivin, cyclin B1 and BAG1) on 52 patients who enrolled on TAILORx. Immunohistochemistry for the protein markers was performed on whole tissue sections. Classification and regression tree (CART) analysis correctly classified 69% of cases into Oncotype DX risk categories based on the expression of PR, survivin and nuclear pleomorphism. All tumours with PR staining (Allred score ≥ 2) and marked nuclear pleomorphism were in the high-risk category. No case with PR <2, low survivin (≤ 15.5%) and nuclear pleomorphism <3 was high-risk. Similarly, 77% of cases were correctly classified into TAILORx categories based on nuclear pleomorphism, survivin, BAG1 and cyclin B1. Ki67 was the only variable that predicted the absolute RS with a cut-off for positivity of 15% (p = 0.003). In conclusion, CART revealed key predictors including proliferation markers, PR and nuclear pleomorphism that correctly classified over two thirds of ER-positive NN cancers into Oncotype DX and TAILORx risk categories. These variables could be used as an alternative to the RT-PCR assay to reduce the number of patients requiring Oncotype DX testing.

Prognostic significance of deregulated dicer expression in breast cancer.

BACKGROUND: Dicer, an RNase III-type endonuclease, is the key enzyme involved in RNA interference and microRNA pathways. Aberrant expression of Dicer is reported in several human cancers. Our aim was to assess the prognostic role of Dicer in breast cancer. METHODS: The entire series comprised 666 invasive breast cancers (IBCs), 480 DCIS cases (397 associated with IBC and 83 pure DCIS) and 305 lymph node metastases. Cytoplasmic Dicer expression by immunohistochemistry was scored as negative (no staining) and positive (weak, moderate or strong staining). RESULTS: Dicer staining was assessable in 446 IBC, 128 DCIS and 101 lymph node metastases. Expression of Dicer was observed in 33% (145/446) of IBCs, 34% (44/128) of DCIS and 57% (58/101) of lymph node metastases. Dicer expression was increased in nodal metastases compared to primary tumours (p<0.001); and was associated with ER negativity (p<0.001), HER2 positivity (p<0.001), high Ki67 labeling index (p<0.001) and expression of basal-like biomarkers (p = 0.002). Dicer positivity was more frequent in the HER2 overexpressing (p<0.001) and basal-like (p = 0.002) subtypes compared to luminal A subtype. Dicer expression was associated with reduced overall survival (OS) on univariate analysis (p = 0.058) and remained an independent predictor of OS on multivariate analysis (HR 2.84, 95% CI 1.43-5.62, p = 0.003), with nodal status (HR 2.61, 95% CI 1.18-5.80, p = 0.018) and PR (HR 0.28, 95% CI 0.13-0.59, p = 0.001). Further, moderate or strong expression of Dicer was associated with improved disease-free survival in the HER2-overexpressing subtype compared to negative or weak expression (p = 0.038). CONCLUSION: Deregulated Dicer expression is associated with aggressive tumour characteristics and is an independent prognostic factor for OS. Our findings suggest that Dicer is an important prognostic marker in breast cancer and that its prognostic role may be subtype specific.

Relationship between circulating and tissue microRNAs in a murine model of breast cancer.

MiRNAs are key regulators of tumorigenesis that are aberrantly expressed in the circulation and tissue of patients with cancer. The aim of this study was to determine whether miRNA dysregulation in the circulation reflected similar changes in tumour tissue. Athymic nude mice (n = 20) received either a mammary fat pad (n = 8, MFP), or subcutaneous (n = 7, SC) injection of MDA-MB-231 cells. Controls received no tumour cells (n = 5). Tumour volume was monitored weekly and blood sampling performed at weeks 1, 3 and 6 following tumour induction (total n = 60). Animals were sacrificed at week 6 and tumour tissue (n = 15), lungs (n = 20) and enlarged lymph nodes (n = 3) harvested. MicroRNAs were extracted from all samples (n = 98) and relative expression quantified using RQ-PCR. MiR-221 expression was significantly increased in tumour compared to healthy tissue (p<0.001). MiR-10b expression was significantly higher in MFP compared to SC tumours (p<0.05), with the highest levels detected in diseased lymph nodes (p<0.05). MiR-10b was undetectable in the circulation, with no significant change in circulating miR-221 expression detected during disease progression. MiR-195 and miR-497 were significantly decreased in tumour tissue (p<0.05), and also in the circulation of animals 3 weeks following tumour induction (p<0.05). At both tissue and circulating level, a positive correlation was observed between miR-497 and miR-195 (r = 0.61, p<0.001; r = 0.41, p<0.01 respectively). This study highlights the distinct roles of miRNAs in circulation and tissue. It also implicates miRNAs in disease dissemination and progression, which may be important in systemic therapy and biomarker development.