Outcome of kidney transplantations from ≥65-year-old deceased donors with acute kidney injury

Kidney transplantation (KT) from donors with acute kidney injury (AKI) has been associated with delayed graft function (DGF) but similar graft survival compared with KT from donors without AKI. Kidneys from ≥65-year-old donors with comorbidities are more susceptible to cold ischemia time and DGF and it is unknown whether such elderly kidneys with AKI can also be transplanted with satisfactory outcomes. All KTs from ≥65-year-old donors performed at our centre from 1999 to 2019 (n = 233) were retrospectively analysed and short- as well as long-term outcomes were compared for KTs from donors with (n = 64) and without AKI (n = 169). There were no significant differences regarding the frequency of DGF as well as the estimated glomerular filtration rate (eGFR) one and three years post-transplant between the no-AKI and the AKI group (DGF: no-AKI 30.2% vs. AKI 40.6%, P = 0.17; eGFR at one-year: 31.9 ml/min/1.73m² vs. 35.5 ml/min/1.73m² , P = 0.32; at three-years: 33.8 ml/min/1.73m² vs. 40.9 ml/min/1.73m² , P = 0.18; respectively). Death-censored graft survival and patient survival were also not significantly different. Multivariable Cox regression analysis did not identify AKI as a significant risk factor for graft loss or death. Following careful donor and recipient selection, kidneys from ≥65-year-old AKI donors may potentially be transplanted with satisfactory outcomes. This article is protected by copyright. All rights reserved.

Impact of cardiopulmonary resuscitation on outcome of kidney transplantations from braindead donors aged ≥65 years

Patients with a history of cardiopulmonary resuscitation (CPR) and subsequent brain death are frequently evaluated for organ donation. Whether kidneys from ≥65-year-old braindead donors with a history of CPR can be transplanted with satisfactory outcomes is unknown. All kidney transplants (KT) from ≥65-year-old donors performed at our centre from 1999 to 2018 (n = 185) were retrospectively analysed and outcome was compared for KTs from donors with and without a history of CPR (n = 27 and n = 158, respectively). No significant differences in the incidence of delayed graft function (DGF) as well as one- and three-year graft function were observed between the CPR and the no-CPR group (DGF: 26.0% vs 31.0%, P = 0.76; one-year serum creatinine: 150.4 μmol/l vs 177.0 μmol/l, P = 0.11; three-year serum creatinine: 150.4 μmol/l vs 168.2 μmol/l, P = 0.52, respectively). Death-censored graft survival was comparable after one and five years (CPR group: 81.5% and 76.7% vs no-CPR group: 86.6% and 75.7%, P = 0.70). Likewise, patient survival was not significantly different. Multivariable Cox regression analysis also did not identify CPR as a significant risk factor for graft loss or death. Our study suggests that, following stringent donor selection, the outcome of KTs from ≥65-year-old braindead donors with and without a history of CPR is comparable. This article is protected by copyright. All rights reserved.

Strong Associations Between Inflammation, Pruritus and Mental Health in Dialysis Patients

Pruritus, impaired mental health and inflammation contribute to morbidity in end-stage renal disease. There are no studies on all 3 conditions. We therefore obtained inflammatory parameter data (C-reactive protein and interleukin-6), pruritus data and psychological test data (36-Item Short-Form Health Survey, "Allgemeine Depressionsskala" and Toronto Alexithymia Scale-20) for 19 dialysis patients with pruritus, 20 dialysis patients without pruritus and 15 healthy controls. Non-parametric hierarchical clustering revealed 3 clusters of parameters: one mainly driven by pruritus scores (chronic kidney disease-associated pruritus cluster), one by mental health scores (mental health cluster) and one by inflammatory parameters (inflammatory cluster). Factor analysis showed strong associations (mental health cluster/chronic kidney disease-associated pruritus cluster, r=-0.49; mental health cluster/inflammatory cluster, r=-0.52; inflammatory cluster/chronic kidney disease-associated pruritus cluster, r=0.48). For the first time, complete correlations between inflammation, mental health and pruritus in dialysis patients have been established. As all 3 conditions are associated with mortality, knowledge about their interdependence helps to understand end-stage renal disease pathophysiology.

Refined risk stratification for thoracoscopic lobectomy or segmentectomy

Background

Given the wide adoption of thoracoscopic lobectomy and positive effect of the thoracoscopic approach for improving postoperative outcomes, questions have arisen regarding the validity of previously published risk assessment models. We sought to review the reliability of the established predictors for patients undergoing thoracoscopic lobectomy.

Methods

From January 2009 to May 2017, 606 patients (275 women, 331 men; median age 67 years) underwent thoracoscopic lobectomy or segmentectomy for confirmed or suspected early-stage lung cancer or metastasis at our institution. Logistic regression analyses were performed to determine the predictors of postoperative complications, followed by assessments of causal inference.

Results

The postoperative mortality, pulmonary complication, cardiovascular complication and overall morbidity rates were 1.0%, 8.9%, 5.8% and 18.0%, respectively. While the American Society of Anesthesiologists physical status (ASA-PS) emerged as an independent morbidity predictor, only a slightly significant association between lung function determinants and overall morbidity was found in the univariable regression analyses. Regarding causal inference, inverse probability of treatment weighting using propensity scores revealed 2- and 1.7-fold increases in the odds of cardiopulmonary complications and overall morbidity in patients with ASA-PS grade 3 or 4 compared with those with ASA-PS grade 1 or 2 (OR =2.116, 95% CI: 1.252-3.577, P=0.005; OR =1.740, 95% CI: 1.095-2.765, P=0.019, respectively).

Conclusions

Our results suggested that the current physiologic evaluation algorithm is also applicable to major lung resection via thoracoscopic approach. ASA-PS is an easily assessable factor capable of predicting major complications following thoracoscopic lobectomy in patients properly selected in compliance with the current guideline. It is recommended to incorporate the ASA-PS into the existing algorithm for more accurate risk stratification in this patient population.

Preoperative serum lactate dehydrogenase level as a predictor of major complications following thoracoscopic lobectomy: a propensity-adjusted analysis

OBJECTIVES

Despite the positive effects of a thoracoscopic approach on improving postoperative outcomes, the risk of major complications following thoracoscopic lobectomy is not negligible. We sought to assess the usefulness of the preoperative determination of serum biomarkers to refine risk stratification in this patient population.

METHODS

From 2009 to 2017, 626 patients (285 women, 341 men; median age: 67 years) underwent thoracoscopic lobectomy or anatomical segmentectomy for confirmed or suspected early-stage lung cancer or metastasis at our institution. Preoperative serum biomarkers, including albumin, C-reactive protein, haemoglobin and lactate dehydrogenase (LDH), were examined as predictors of postoperative cardiopulmonary complications using logistic regression analyses followed by causal inference.

RESULTS

The 90-day mortality, cardiopulmonary complication and overall morbidity rates were 1.0%, 13.1% and 18.1%, respectively. Although serum albumin, C-reactive protein and haemoglobin were not associated with cardiopulmonary complications in regression analyses, preoperative serum LDH level emerged as an independent morbidity predictor (odds ratio 1.008, 95% confidence interval 1.002-1.013; P = 0.006). The causal inference using the covariate balancing generalized propensity score methodology demonstrated similar results and an approximately positive linear relationship between the odds of cardiopulmonary complications and preoperative serum LDH level. For every 100 U/l increase in preoperative serum LDH, a 2-fold increase in the odds of cardiopulmonary complications was observed.

CONCLUSIONS

Our results suggest that the preoperative serum LDH level is an independent predictor of 90-day cardiopulmonary complications following thoracoscopic lobectomy or segmentectomy, even in properly selected patients. Therefore, we recommend incorporating early serum LDH measurements as a readily available method into the risk assessment process prior to major lung resection.

Impact of comorbidity burden on morbidity following thoracoscopic lobectomy: a propensity-matched analysis

Background

Given the positive effect of a thoracoscopic approach on improving postoperative outcomes, it is reasonable to speculate whether an increased comorbidity burden is related to higher morbidity following thoracoscopic lobectomy. We sought to evaluate the impact of comorbidity burden on adverse postoperative outcomes in this patient population.

Methods

A retrospective review of our institutional database included 512 patients undergoing thoracoscopic lobectomy for early-stage non-small cell lung cancer (NSCLC) from 2009 through 2016. Comorbidity burden was assessed by the Charlson comorbidity index (CCI) and classified as high (CCI ≥3) or low (CCI <3) grade. Propensity score matching and random effects model were performed.

Results

Patients included 228 women and 284 men with a median age of 67 years. High and low comorbidity burdens were found in 193 and 319 patients, respectively. The postoperative mortality, pulmonary and cardiovascular complication rates and overall morbidity in patients with high comorbidity burden were comparable to those with low comorbidity burden (1.6% vs. 0.6%, 9.3% vs. 8.5%, 6.2% vs. 6.0%, 24.4% vs. 22.9%, respectively). Similar results were seen after propensity score matching, which balanced differences in demographics and preoperative characteristics between the comorbidity groups. On the analyses of propensity-matched data using generalized linear mixed model, a high comorbidity burden was not related to greater postoperative complication rates.

Conclusions

Our results suggest that thoracoscopic lobectomy can be performed with low mortality and reasonable morbidity in lung cancer patients presenting with multiple comorbid diseases. The presence of a high comorbidity burden measured by CCI does not have a perceptible impact on adverse postoperative outcomes following thoracoscopic lobectomy.

Is Mistletoe Treatment Beneficial in Invasive Breast Cancer? A New Approach to an Unresolved Problem

BACKGROUND/AIM

In this retrospective study, we compared breast cancer patients treated with and without mistletoe lectin I (ML-I) in addition to standard breast cancer treatment in order to determine a possible effect of this complementary treatment.

PATIENTS AND METHODS

This study included 18,528 patients with invasive breast cancer. Data on additional ML-I treatments were reported for 164 patients. We developed a "similar case" method with a distance measure retrieved from the beta variable in Cox regression to compare these patients, after stage adjustment, with their non-ML-1 treated counterparts in order to answer three hypotheses concerning overall survival, recurrence free survival and life quality.

RESULTS

Raw data analysis of an additional ML-I treatment yielded a worse outcome (p=0.02) for patients with ML treatment, possibly due to a bias inherent in the ML-I-treated patients. Using the "similar case" method (a case-based reasoning approach) we could not confirm this harm for patients using ML-I. Analysis of life quality data did not demonstrate reliable differences between patients treated with ML-I treatment and those without proven ML-I treatment.

CONCLUSION

Based on a "similar case" model we did not observe any differences in the overall survival (OS), recurrence-free survival (RFS), and quality of life data between breast cancer patients with standard treatment and those who in addition to standard treatment received ML-I treatment.

Globally convergent stochastic optimization with optimal asymptotic distribution

A stochastic gradient descent method is combined with a consistent auxiliary estimate to achieve global convergence of the recursion. Using step lengths converging to zero slower than 1/n and averaging the trajectories, yields the optimal convergence rate of 1/√n and the optimal variance of the asymptotic distribution. Possible applications can be found in maximum likelihood estimation, regression analysis, training of artificial neural networks, and stochastic optimization.

Postoperative survival of lung cancer patients: are there predictors beyond TNM?

BACKGROUND/AIM

We report on survival data of 595 patients with stage I-III lung cancer with respect to TNM classification.

MATERIALS AND METHODS

We constructed a basic model consisting of stage and grade, and assessed the improvement of survival prediction after adding comorbidity data, spirometric data, clinical and laboratory parameters.

RESULTS

Body mass index (BMI) and presence of a cardiac disease reached statistical significance for prediction of overall survival in a Cox regression model. In addition to BMI (<25 kg/m(2)) and the presence of cardiovascular disease, the spirometric variable (FEV1) predicted early death (less than five months postoperatively). When the survival random forest method was employed to predict disease outcome, creatinine levels and VO2 max became additional variables of interest for predicting survival.

CONCLUSION

We propose that our lung cancer database may help to identify variables (aside from histomorphological variables) that are suitable for identifying patients at risk of death after surgical treatment of lung cancer.

Canine scent detection in the diagnosis of lung cancer: revisiting a puzzling phenomenon

Patient prognosis in lung cancer largely depends on early diagnosis. The exhaled breath of patients may represent the ideal specimen for future lung cancer screening. However, the clinical applicability of current diagnostic sensor technologies based on signal pattern analysis remains incalculable due to their inability to identify a clear target. To test the robustness of the presence of a so far unknown volatile organic compound in the breath of patients with lung cancer, sniffer dogs were applied. Exhalation samples of 220 volunteers (healthy individuals, confirmed lung cancer or chronic obstructive pulmonary disease (COPD)) were presented to sniffer dogs following a rigid scientific protocol. Patient history, drug administration and clinicopathological data were analysed to identify potential bias or confounders. Lung cancer was identified with an overall sensitivity of 71% and a specificity of 93%. Lung cancer detection was independent from COPD and the presence of tobacco smoke and food odours. Logistic regression identified two drugs as potential confounders. It must be assumed that a robust and specific volatile organic compound (or pattern) is present in the breath of patients with lung cancer. Additional research efforts are required to overcome the current technical limitations of electronic sensor technologies to engineer a clinically applicable screening tool.

Clinical impacts of histological subtyping primary breast cancer

BACKGROUND

Treatment decisions in breast cancer depend on TNM classification and the assessment of additional variables with have an impact on survival. We examined whether histological subtyping breast cancer as either ductal or lobular is related to disease outcome.

PATIENTS AND METHODS

We examined a large data base of 14198 breast cancer patients.

RESULTS

Histological sub-classification of invasive breast cancer as either ductal or lobular is not correlated with disease outcome. However, the data further showed that invasive lobular carcinomas have a higher probability of being oestrogen receptor (ER)- and progesterone receptor (PR)-positive and a lower probability of being c-erbB2-positive. They also showed a higher average age at the time of diagnosis in comparison with invasive ductal carcinoma. Local recurrence rates were lower in invasive lobular carcinoma in comparison with invasive ductal carcinoma (3.5% vs. 6.2%; p = 0.031). The multivariable Cox regression analysis showed that ER, PR, nodal status, grade and tumour size predicted disease outcome with statistical significance, while the histological subtype (invasive ductal or lobular) was not a significant predictor of disease outcome.

CONCLUSION

Histological sub-classification of invasive breast cancer as either ductal or lobular is not correlated with disease outcome. On the other hand our data gives some indication that lobular and ductal breast cancer appear to be different biological entities.

Polymorphic loci of E2F2, CCND1 and CCND3 are associated with HER2 status of breast tumors

Overexpression of the human epidermal growth factor receptor 2 (HER2) in breast tumors is associated with bad prognosis. Therefore, it is highly relevant to further improve understanding of the regulatory mechanisms of HER2 expression. In addition to gene amplification, transcriptional regulation plays a crucial role in HER2 overexpression. In this study, we analyzed 3 polymorphisms E2F2_-5368_A>G, CCND1_870_A>G and CCND3_-677_C>T located in genes involved in cell cycle regulation in the GENICA population-based and age-matched breast cancer case-control study from Germany. We genotyped 1,021 cases and 1,015 controls by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Statistical analyses were performed by conditional logistic regression. We observed no differences in genotype frequencies between breast cancer cases and controls. Subgroup analysis showed associations between carriers of the E2F2_-5368_G allele (OR: 0.60, 95% CI: 0.42-0.85), carriers of the CCND1_870_G allele (OR: 0.66, 95% CI: 0.45-0.96) and carriers of the CCND3_-677_T allele (OR: 1.72, 95% CI: 1.20-2.49) and HER2 expression in breast tumors. This finding points to an association of an increased expression of these cell cycle regulators with lower expression of HER2. An explanation for this observation might be that low expression of E2F2, CCND1 and CCND3 decrease levels of factors down-regulating HER2. We conclude that the analyzed polymorphisms located in E2F2, CCND1 and CCND3 are potential markers for HER2 status of breast tumors.

Morbidity and mortality after pneumonectomy in smokers with NSCLC

OBJECTIVE

Perioperative morbidity and mortality in patients receiving pneumonectomy because of non-small cell lung cancer (NSCLC) remains quite high. The aim of this study is to identify risk factors to minimize perioperative mortality and morbidity.

PATIENTS AND METHOD

The results of 156 Patients who received pneumonectomy between 1995 and 2004 were reviewed retrospectively. All patients had stage I or II NSCLC. In 81 cases a right sided and in 75 a left sided pneumonectomy was performed. Cardiopulmonary function tests were sufficient for pneumonectomy.

RESULTS

Overall perioperative 30-day mortality was 7.1% (n=11), in hospital mortality 8.3% (n=13). The cause was sepsis in 6 cases, cardiac failure in 4 cases, and respiratory insufficiency in 3 cases. In univariable and multivariable regression analysis considering mortality, none of the prognostic factors reached significance. The odds ratio for postoperative death was 1.6 fold for smokers in comparison to non smokers. Complications after pneumonectomy were seen in 34.6%, with arrhythmia in 16.0%, sepsis in 1.9% and bronchopleural fistula (BPF) occurring in 6.4%. Smoking and intraoperative blood loss >500 ml were highly significant perioperative risk factors.

CONCLUSION

Smoking until operation and intraoperative blood loss were independent postoperative risk factors leading to complications after pneumonectomy for NSCLC. The risk for complications was 2.8-fold higher for smokers.

Full-thickness resection with myocutaneous flap reconstruction for locally recurrent breast cancer

BACKGROUND

Despite available recommendations, therapeutic procedures of locally recurrent breast cancer are very different. This retrospective study presents the possibilities and results of complete, full-thickness chest wall resection.

METHODS

Between 1985 and 2006, 63 women (mean age, 58 years) with local recurrence of breast cancer invading the chest wall underwent chest wall resection with myocutaneous flap coverage and are included in this study. Adequate lung, cardiovascular, renal, and hepatic functions were additional eligibility requirements for inclusion. Preoperative known extrapulmonary metastases, pleural dissemination, and Eastern Cooperative Oncology Group (ECOG) status 3 or 4 were exclusion criteria. Survival rates were calculated by the Kaplan-Meier method. Univariable and multivariable Cox regression analysis was used for relative risk factors.

RESULTS

The median interval between operation for the primary tumor and of the local recurrence was 89 months, with median follow-up at 28 months. In the total collective, cumulative 5-, 10- and 15-year survival rates were 46%, 29%, and 22%, respectively, with a median survival of 56 months. R0 resection was associated with a 5-year survival of 50.4%. Prognostic factors were patient age at the time of the primary operation and tumor invasion of bony structures. Mortality was 1.6% and morbidity was 25%.

CONCLUSIONS

Full-thickness chest wall resection of locally recurrent breast cancer performed by a team of thoracic and plastic surgeons provides the best survival rates, with low mortality and morbidity. An earlier application of this method may lead to further improvement of these results.

Statins do not adversely affect post-interventional residual platelet aggregation and outcomes in patients undergoing coronary stenting treated by dual antiplatelet therapy

AIMS

There are growing data suggesting a clinical relevance of residual platelet aggregation (RPA) in patients undergoing PCI. Drug-drug interaction of statins and clopidogrel has been controversially discussed in ex vivo studies and clinical trials. The aim of the present study was to investigate the effects of peri-procedural statin medication on the metabolization of aspirin and clopidogrel with regard to platelet aggregation and clinical outcome in patients undergoing coronary intervention.

METHODS AND RESULTS

Patients with coronary stenting for symptomatic coronary artery disease are routinely evaluated by platelet function analysis in a monocentre registry, and for the present study, a consecutive cohort of 1155 patients were analysed. About 87.7% of the patients were treated with statins at the time of platelet function analysis. Residual platelet activity assessed by adenosine diphosphate (20 micromol/L)-induced platelet aggregation was not significantly influenced by statin treatment. Nor the significant effects of CYP3A4-metabolization pathway on post-treatment aggregation were recorded, although there was even a trend to lower RPA values in patients treated with CYP3A4-metabolized statins. Further, in an inter-individual analysis comparing patients treated with CYP3A4- and non-CYP3A4-metabolized statins, no time-dependent difference of clopidogreĺs anti-aggregatory effects was observed. Clinical follow-up of major adverse events (myocardial infarction, ischaemic stroke, death) in 991 patients within 3 months revealed no significant adverse effects of statin treatment on clinical outcome. Instead, statin treatment was independently associated with lower incidence of composite events (HR 0.44, 95% confidence interval 0.23-0.83, P = 0.01).

CONCLUSION

Peri-procedural co-administration of statins does not increase the post-interventional RPA in cardiovascular patients treated with dual antiplatelet therapy and does not worsen the clinical prognosis of these patients.

Analysis of the distribution of functionally relevant rare codons

Background

The substitution of rare codons with more frequent codons is a commonly applied method in heterologous gene expression to increase protein yields. However, in some cases these substitutions lead to a decrease of protein solubility or activity. To predict these functionally relevant rare codons, a method was developed which is based on an analysis of multisequence alignments of homologous protein families.

Results

The method successfully predicts functionally relevant codons in fatty acid binding protein and chloramphenicol acetyltransferase which had been experimentally determined. However, the analysis of 16 homologous protein families belonging to the α/β hydrolase fold showed that functionally rare codons share no common location in respect to the tertiary and secondary structure.

Conclusion

A systematic analysis of multisequence alignments of homologous protein families can be used to predict rare codons with a potential impact on protein expression. Our analysis showed that most genes contain at least one putative rare codon rich region. Rare codons located near to those regions should be excluded in an approach of improving protein expression by an exchange of rare codons by more frequent codons.

Role of genetic and nongenetic factors for fluorouracil treatment-related severe toxicity: a prospective clinical trial by the German 5-FU Toxicity Study Group

PURPOSE

To assess the predictive value of polymorphisms in dihydropyrimidine dehydrogenase (DPYD ), thymidylate synthase (TYMS ), and methylene tetrahydrofolate reductase (MTHFR ) and of nongenetic factors for severe leukopenia, diarrhea, and mucositis related to fluorouracil (FU) treatment.

PATIENTS AND METHODS

A multicenter prospective clinical trial included 683 patients with cancer treated with FU monotherapy. Toxicity was documented according to World Health Organization grades. DPYD, TYMS, and MTHFR genotypes were determined, and DPYD was resequenced in patients with severe toxicity.

RESULTS

Grade 3 to 4 toxicity occurred in 16.1% of patients. The sensitivity of DPYD*2A genotyping for overall toxicity was 5.5% (95%CI, 0.02 to 0.11), with a positive predictive value of 0.46 (95% CI, 0.19 to 0.75; P = .01). Inclusion of additional DPYD variants improved prediction only marginally. Analysis according to toxicity type revealed significant association of DPYD with mucositis and leukopenia, whereas TYMS was associated with diarrhea. Genotype, female sex, mode of FU administration, and modulation by folinic acid were identified as independent risk factors by multivariable analysis. A previously unrecognized significant interaction was found between sex and DPYD, which resulted in an odds ratio for toxicity of 41.8 for male patients (95% CI, 9.2 to 190; P < .0001) but only 1.33 (95% CI, 0.34 to 5.2) in female patients. Homozygosity for the TYMS enhancer region double repeat allele increased risk for toxicity 1.6-fold (95% CI, 1.08 to 2.22; P = .02).

CONCLUSION

DPYD, TYMS, and MTHFR play a limited role for FU related toxicity but a pronounced DPYD gene/sex-interaction increases prediction rate for male patients. Toxicity risk assessment should include sex, mode of administration, and folinic acid as additional predictive factors.

Breast cancer: a candidate gene approach across the estrogen metabolic pathway

Polymorphisms within the estrogen metabolic pathway are prime candidates for a possible association with breast cancer risk. We investigated 11 genes encoding key proteins of this pathway for their potential contribution to breast cancer risk. Of these CYP17A1, CYP19A1, EPHX1, HSD17B1, SRD5A2, and PPARG2 participate in biosynthesis, CYP1A1, CYP1B1, COMT, GSTP1, and SOD2 in catabolism and detoxification. We performed a population-based case-control study with 688 incident breast cancer cases and 724 controls from Germany and genotyped 18 polymorphisms by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), PCR based RFLP (restriction fragment length polymorphism), and TaqMan allelic discrimination. Genotype frequencies were compared between cases and controls and odds ratios were calculated by conditional logistic regression. Further statistical analyses were based on cluster analysis, multifactor dimensionality reduction, logic regression, and global testing. Single factor analyses pointed to CYP1B1_1294_GG as a possible breast cancer risk modulator (OR = 2.57; 95% CI: 1.34-4.93) and two way stratification suggested associations between BMI > or = 30 kg/m(2) and COMT_472_GG (P = 0.0076 and P = 0.0026), BMI < 20 kg/m(2) and HSD17B1_937_GG (P = 0.0082) as well as CYP17A1_-34_CC and HRT use > or =10 years (P = 0.0063). Following correction for multiple testing none of these associations remained significant. No significant association between breast cancer risk and genetic polymorphisms was observed in multifactor analyses. The tested polymorphisms of the estrogen metabolic pathway may not play a direct role in breast cancer risk. Therefore, future association studies should be extended to other polymorphisms and other regulatory pathways.

Systematic interpretation of microarray data using experiment annotations

BACKGROUND

Up to now, microarray data are mostly assessed in context with only one or few parameters characterizing the experimental conditions under study. More explicit experiment annotations, however, are highly useful for interpreting microarray data, when available in a statistically accessible format.

RESULTS

We provide means to preprocess these additional data, and to extract relevant traits corresponding to the transcription patterns under study. We found correspondence analysis particularly well-suited for mapping such extracted traits. It visualizes associations both among and between the traits, the hereby annotated experiments, and the genes, revealing how they are all interrelated. Here, we apply our methods to the systematic interpretation of radioactive (single channel) and two-channel data, stemming from model organisms such as yeast and drosophila up to complex human cancer samples. Inclusion of technical parameters allows for identification of artifacts and flaws in experimental design.

CONCLUSION

Biological and clinical traits can act as landmarks in transcription space, systematically mapping the variance of large datasets from the predominant changes down toward intricate details.

A novel functional polymorphism in the transforming growth factor-beta2 gene promoter and tumor progression in breast cancer

Transforming growth factor-beta (TGF-beta), a multifunctional growth factor, plays an important role in breast cancer. There is increasing evidence that enhanced expression of TGF-beta promotes breast cancer progression contributing to metastasis and invasiveness of the tumor. We identified a functional polymorphism in the TGFB2 promoter, a 4-bp insertion at position -246 relative to the transcriptional start site (-246ins). Transient transfection experiments showed that the -246ins polymorphism significantly increased TGFB2 promoter activity in breast cancer cells. Electrophoretic mobility shift assays revealed binding of the transcription factor Sp1 to the -246ins allele. Overexpression of Sp1 enhanced promoter activity of the -246ins allele, demonstrating that Sp1 mediates transcriptional activation. Furthermore, the -246ins allele was associated with enhanced TGF-beta(2) expression in breast cancer tissue (P = 0.0005). To evaluate the role of the polymorphism in breast cancer, frequency of the -246ins allele was determined in breast cancer patients (n = 78) and healthy female controls (n = 143). No significant differences were found. However, the presence of the -246ins allele was associated with lymph node metastasis (P = 0.003). The -246ins allele was a significant predictor for lymph node metastasis independent of estrogen and progesterone receptor status in a multivariate logistic regression analysis (P = 0.0118, odds ratio, 5.18; 95% confidence interval, 1.44-18.62). We provide evidence that the TGFB2 -246ins polymorphism leads to enhanced TGF-beta(2) expression levels in vivo and might thereby contribute to tumor progression and development of metastases.

c-erbB2 and topoisomerase IIalpha protein expression independently predict poor survival in primary human breast cancer: a retrospective study

Introduction

c-erbB2 (also known as HER-2/neu) and topoisomerase IIα are frequently overexpressed in breast cancer. The aim of the study was to analyze retrospectively whether the expression of c-erbB2 and topoisomerase IIα protein influences the long-term outcome of patients with primary breast cancer.

Methods

In this study c-erbB2 and topoisomerase IIα protein were evaluated by immunohistochemistry in formalin-fixed paraffin-embedded tissue from 225 samples of primary breast cancer, obtained between 1986 and 1998. The prognostic value of these markers was analyzed.

Results

Of 225 primary breast tumor samples, 78 (34.7%) showed overexpression of either c-erbB2 (9.8%) or topoisomerase IIα protein (24.9%), whereas in 21 tumors (9.3%) both proteins were found to be overexpressed. Patients lacking both c-erbB2 and topoisomerase IIα overexpression had the best long-term survival. Overexpression of either c-erbB2 or topoisomerase IIα was associated with shortened survival, whereas patients overexpressing both c-erbB2 and topoisomerase IIα showed the worst disease outcome (P < 0.0001). Treatment with anthracyclines was not capable of reversing the negative prognostic impact of topoisomerase IIα or c-erbB2 overexpression.

Conclusion

The results of this exploratory study suggest that protein expression of c-erbB2 and topoisomerase IIα in primary breast cancer tissues are independent prognostic factors and are not exclusively predictive factors for anthracycline response in patients with primary breast cancer.

Integration of GO annotations in Correspondence Analysis: facilitating the interpretation of microarray data

MOTIVATION

The functional interpretation of microarray datasets still represents a time-consuming and challenging task. Up to now functional categories that are relevant for one or more experimental context(s) have been commonly extracted from a set of regulated genes and presented in long lists.

RESULTS

To facilitate interpretation, we integrated Gene Ontology (GO) annotations into Correspondence Analysis to display genes, experimental conditions and gene-annotations in a single plot. The position of the annotations in these plots can be directly used for the functional interpretation of clusters of genes or experimental conditions without the need for comparing long lists of annotations. Correspondence Analysis is not limited in the number of experimental conditions that can be compared simultaneously, allowing an easy identification of characterizing annotations even in complex experimental settings. Due to the rapidly increasing amount of annotation data available, we apply an annotation filter. Hereby the number of displayed annotations can be significantly reduced to a set of descriptive ones, further enhancing the interpretability of the plot. We validated the method on transcription data from Saccharomyces cerevisiae and human pancreatic adenocarcinomas.

AVAILABILITY

The M-CHiPS software is accessible for collaborators at http://www.mchips.org

Impact of mistletoe lectin binding in breast cancer

BACKGROUND

One of the most often used complementary or alternative anticancer therapeutics for breast cancer is mistletoe extract with Viscum album lectin (VAA-1) as the leading component. The aim of this study was to determine the correlation between VAA-1 binding in breast cancer and disease outcome.

MATERIALS AND METHODS

VAA-1 binding to either tumour cells or tumour infiltrating inflammatory cells was examined by immunohistochemical staining of paraffin tissue sections from breast cancer patients (n=226).

RESULTS

About 34% of breast cancer tumour cells displayed a strong VAA-1 binding. Kaplan-Meier statistics revealed an inverse correlation between disease outcome and presence of strong VAA-1 binding to tumour cells.

CONCLUSION

As binding of VAA-1 indicates the presence of galactose molecules in saccharide structures of the cytoplasm or cell membrane, we conclude that the amount of galactose-containing glycoproteins, mucoproteins and glycolipids in breast cancer tumour cells is related to disease outcome.