Health-state utilities in long-term advanced melanoma survivors comparable with the general population.

BACKGROUND: Checkpoint inhibitors have been shown to substantially improve the survival of patients with advanced melanoma. With this growing group of survivors treated with immunotherapies, assessing their health-state utilities is essential and can be used for the calculation of quality-adjusted life years and for cost-effectiveness analyses. Therefore, we evaluated the health-state utilities in long-term advanced melanoma survivors. METHODS: Health-state utilities were evaluated in a cohort of advanced melanoma survivors 24-36 months (N = 37) and 36-plus months (N = 47) post-ipilimumab monotherapy. In addition, the health-state utilities of the 24-36 months survivor group were assessed longitudinally, and utilities of the combined survival groups (N = 84) were compared with a matched control population (N = 168). The EQ-5D was used to generate health-state utility values, and quality-of-life questionnaires were used to establish correlations and influencing factors of utility scores. RESULTS: Health-state utility scores were similar between the 24-36 months'- and the 36-plus months' survival group (0.81 vs 0.86; p = .22). In survivors, lower utility scores were associated with symptoms of depression (ß = - .82, p = .022) and fatigue burden (ß = - .29, p = .007). Utility scores did not significantly change after 24-36 months of survival, and the utilities of survivors were comparable to the matched control population (0.84 vs 0.87; p = .07). DISCUSSION: Our results show that long-term advanced melanoma survivors treated with ipilimumab monotherapy experience relatively stable and high health-state utility scores.

Chlamydia trachomatis intra-bacterial and total plasmid copy number in clinical urogenital samples.

Chlamydia trachomatis (CT) increases its plasmid numbers when stressed, as occurs in clinical trachoma samples. Most CT tests target the plasmid to increase the test sensitivity, but some only target the chromosome. We investigated clinical urogenital samples for total plasmid copy numbers to assess its diagnostic value and intra-bacterial plasmid copy numbers to assess its natural variation. Both plasmid and chromosome copies were quantified using qPCR, and the plasmid:chromosome ratio (PCr) calculated in two cohorts: (1) 383 urogenital samples for the total PCR (tPCr), and (2) 42 vaginal swabs, with one half treated with propium-monoazide (PMA) to prevent the quantification of extracellular DNA and the other half untreated to allow for both tPCr and intra-bacterial PCr (iPCr) quantification. Mann-Whitney U tests compared PCr between samples, in relation to age and gender. Cohort 1: tPCr varied greatly (1-677, median 16). Median tPCr was significantly higher in urines than vaginal swabs (32 vs. 11, p < 0.001). Cohort 2: iPCr was more stable than tPCr (range 0.1-3 vs. 1-11). To conclude, tPCr in urogenital samples was much more variable than previously described. Transport time and temperature influences DNA degradation, impacting chromosomal DNA more than plasmids and urine more than vaginal samples. Data supports a plasmid target in CT screening assays to increase clinical sensitivity.

Health-related quality of life of long-term advanced melanoma survivors treated with anti-CTLA-4 immune checkpoint inhibition compared to matched controls.

BACKGROUND: Checkpoint inhibitors have changed overall survival for patients with advanced melanoma. However, there is a lack of data on health-related quality of life (HRQoL) of long-term advanced melanoma survivors, years after treatment. Therefore, we evaluated HRQoL in long-term advanced melanoma survivors and compared the study outcomes with matched controls without cancer. MATERIAL AND METHODS: Ipilimumab-treated advanced melanoma survivors without evidence of disease and without subsequent systemic therapy for a minimum of two years following last administration of ipilimumab were eligible for this study. The European Organization for Research and Treatment of Cancer quality of life questionnaire Core 30 (EORTC QLQ-C30), the Multidimensional Fatigue Inventory (MFI), the Hospital Anxiety and Depression Scale (HADS), and the Functional Assessment of Cancer Therapy-Melanoma questionnaire (FACT-M) were administered. Controls were individually matched for age, gender, and educational status. Outcomes of survivors and controls were compared using generalized estimating equations, and differences were interpreted as clinically relevant according to published guidelines. RESULTS: A total of 89 survivors and 265 controls were analyzed in this study. After a median follow-up of 39 (range, 17-121) months, survivors scored significantly lower on physical (83.7 vs. 89.8, difference (diff) = -5.80, p=.005), role (83.5 vs. 90, diff = -5.97, p=.02), cognitive (83.7 vs. 91.9, diff = -8.05, p=.001), and social functioning (86.5 vs. 95.1, diff = -8.49, p= <.001) and had a higher symptom burden of fatigue (23.0 vs. 15.5, diff = 7.48, p=.004), dyspnea (13.3 vs. 6.7, diff = 6.47 p=.02), diarrhea (7.9 vs. 4.0, diff = 3.78, p=.04), and financial impact (10.5 vs. 2.5, diff = 8.07, p=.001) than matched controls. Group differences were indicated as clinically relevant. DISCUSSION: Compared to matched controls, long-term advanced melanoma survivors had overall worse functioning scores, more physical symptoms, and financial difficulties. These data may contribute to the development of appropriate survivorship care.

An introduction to optical super-resolution microscopy for the adventurous biologist.

Ever since the inception of light microscopy, the laws of physics have seemingly thwarted every attempt to visualize the processes of life at its most fundamental, sub-cellular, level. The diffraction limit has restricted our view to length scales well above 250 nm and in doing so, severely compromised our ability to gain true insights into many biological systems. Fortunately, continuous advancements in optics, electronics and mathematics have since provided the means to once again make physics work to our advantage. Even though some of the fundamental concepts enabling super-resolution light microscopy have been known for quite some time, practically feasible implementations have long remained elusive. It should therefore not come as a surprise that the 2014 Nobel Prize in Chemistry was awarded to the scientists who, each in their own way, contributed to transforming super-resolution microscopy from a technological tour de force to a staple of the biologist's toolkit. By overcoming the diffraction barrier, light microscopy could once again be established as an indispensable tool in an age where the importance of understanding life at the molecular level cannot be overstated. This review strives to provide the aspiring life science researcher with an introduction to optical microscopy, starting from the fundamental concepts governing compound and fluorescent confocal microscopy to the current state-of-the-art of super-resolution microscopy techniques and their applications.

Highly controllable direct femtosecond laser writing of gold nanostructures on titanium dioxide surfaces.

A highly reproducible and controllable deposition procedure for gold nanostructures on a titanium dioxide (TiO2) surface using femtosecond laser light has been demonstrated. This is realized by precisely focusing onto the TiO2 surface in the presence of a pure gold ion solution. The deposition is demonstrated both in dot arrays and line structures. Thanks to the multi-photon excitation, we observe that the deposition area of the nanostructures can be confined to a degree far greater than the diffraction limited focal spot. Finally, we demonstrate that catalytic activity with visible light irradiation is enhanced, proving the applicability of our new deposition technique to the catalytic field.

Recent Achievements in Characterizing the Histone Code and Approaches to Integrating Epigenomics and Systems Biology.

Functional epigenetic regulation occurs by dynamic modification of chromatin, including genetic material (i.e., DNA methylation), histone proteins, and other nuclear proteins. Due to the highly complex nature of the histone code, mass spectrometry (MS) has become the leading technique in identification of single and combinatorial histone modifications. MS has now overcome antibody-based strategies due to its automation, high resolution, and accurate quantitation. Moreover, multiple approaches to analysis have been developed for global quantitation of posttranslational modifications (PTMs), including large-scale characterization of modification coexistence (middle-down and top-down proteomics), which is not currently possible with any other biochemical strategy. Recently, our group and others have simplified and increased the effectiveness of analyzing histone PTMs by improving multiple MS methods and data analysis tools. This review provides an overview of the major achievements in the analysis of histone PTMs using MS with a focus on the most recent improvements. We speculate that the workflow for histone analysis at its state of the art is highly reliable in terms of identification and quantitation accuracy, and it has the potential to become a routine method for systems biology thanks to the possibility of integrating histone MS results with genomics and proteomics datasets.

Virology analyses of HCV genotype 4 isolates from patients treated with simeprevir and peginterferon/ribavirin in the Phase III RESTORE study.

Simeprevir is a hepatitis C virus NS3/4A protease inhibitor. Hepatitis C virus baseline NS3/4A polymorphisms and emerging mutations were characterized in treatment-naїve and treatment-experienced genotype 4-infected patients treated with simeprevir+peginterferon/ribavirin in the RESTORE study. Population sequencing of the NS3/4A region was performed and in vitro simeprevir activity against site-directed mutants or chimeric replicons with patient-derived NS3 protease sequences was assessed in a transient replicon assay. Simeprevir remained active against most (83/91 [91%]) baseline isolates tested in the chimeric replicon assay. Eight baseline isolates reduced simeprevir activity; these carried I132L or D168E substitutions reducing simeprevir median activity by 4.6- and 39-fold, respectively. Six of these eight isolates were from patients achieving sustained virologic response. Baseline NS3 Q80K polymorphism was not observed in the genotype 4-infected patients. Of the 107 simeprevir-treated patients, 37 did not achieve sustained virologic response for any reason. Of the 32 patients who failed treatment and had sequencing information, 28 (88%) had emerging mutations at NS3 positions 80, 122, 155, 156 and/or 168 at time of failure, similar to those in genotype 1. Emerging mutations were mainly D168V and D168E alone or combined with mutations at position 80. In general, isolates obtained at time of failure displayed high-level in vitro resistance to simeprevir (fold change ≥50) in a chimeric replicon assay with a median simeprevir fold change value of 440, consistent with observed mutations. In conclusion, emerging mutations in genotype 4 patients failing simeprevir+peginterferon/ribavirin treatment were similar to those in genotype 1 and conferred high-level resistance to simeprevir.

A porcine model of osteosarcoma.

We previously produced pigs with a latent oncogenic TP53 mutation. Humans with TP53 germline mutations are predisposed to a wide spectrum of early-onset cancers, predominantly breast, brain, adrenal gland cancer, soft tissue sarcomas and osteosarcomas. Loss of p53 function has been observed in >50% of human cancers. Here we demonstrate that porcine mesenchymal stem cells (MSCs) convert to a transformed phenotype after activation of latent oncogenic TP53(R167H) and KRAS(G12D), and overexpression of MYC promotes tumorigenesis. The process mimics key molecular aspects of human sarcomagenesis. Transformed porcine MSCs exhibit genomic instability, with complex karyotypes, and develop into sarcomas on transplantation into immune-deficient mice. In pigs, heterozygous knockout of TP53 was sufficient for spontaneous osteosarcoma development in older animals, whereas homozygous TP53 knockout resulted in multiple large osteosarcomas in 7-8-month-old animals. This is the first report that engineered mutation of an endogenous tumour-suppressor gene leads to invasive cancer in pigs. Unlike in Trp53 mutant mice, osteosarcoma developed in the long bones and skull, closely recapitulating the human disease. These animals thus promise a model for juvenile osteosarcoma, a relatively uncommon but devastating disease.

Incidence of virological failure and emergence of resistance with twice-daily vs every 8-h administration of telaprevir in the OPTIMIZE study.

The OPTIMIZE study demonstrated noninferior efficacy between telaprevir (TVR) twice daily (bid) vs every 8-h (q8h) administration. This analysis compared the selective pressure of both dosing regimens by characterisation of the hepatitis C virus (HCV) variants emerging in genotype 1 (G1) HCV-infected patients who did not achieve sustained virological response (SVR). HCV NS3•4A population sequencing was performed at baseline and time of failure (viral breakthrough, stopping rule or relapse). TVR-resistant variants were classified by fold change in inhibitory concentration (IC50 ). Baseline TVR-resistance was low (<5%) and did not preclude achieving SVR in either arm. The proportion of patients with TVR-resistant variants at time of failure was similar in the bid (15%) and q8h (17%) dosing arms. The majority of variants and virological failures occurred in G1a patients, and mutations V36M, R155K and R155T (G1a), and V36A, T54A and A156S (G1b) were significantly enriched in both treatment arms. The number and type of emerging TVR-resistant variants in non-SVR patients were comparable between treatment arms and were consistent with previous observations. No differences in viral resistance profiles were observed between TVR-based treatment arms in non-SVR patients, indicating a similar selective pressure of TVR bid and q8h dosing.

[Cost-minimization analysis of subcutaneous abatacept in the treatment of rheumatoid arthritis in Spain]. / Análisis de minimización de costes de abatacept subcutáneo en el tratamiento de la artritis reumatoide en España.

OBJECTIVE: To compare the cost of treating rheumatoid arthritis patients that have failed an initial treatment with methotrexate, with subcutaneous abatacept versus other first-line biologic disease-modifying antirheumatic drugs. METHOD: Subcutaneous abatacept was considered comparable to intravenous abatacept, adalimumab, certolizumab pegol, etanercept, golimumab, infliximab and tocilizumab, based on indirect comparison using mixed treatment analysis. A cost-minimization analysis was therefore considered appropriate. The Spanish Health System perspective and a 3 year time horizon were selected. Pharmaceutical and administration costs (Euros 2013) of all available first-line biological disease-modifying antirheumatic drugs were considered. Administration costs were obtained from a local costs database. Patients were considered to have a weight of 70 kg. A 3% annual discount rate was applied. Deterministic and probabilistic sensitivity analyses were performed. RESULTS: Subcutaneous abatacept proved in the base case to be less costly than all other biologic antirrheumatic drugs (ranging from Euros -831.42 to Euros -9,741.69 versus infliximab and tocilizumab, respectively). Subcutaneous abatacept was associated with a cost of Euros 10,760.41 per patient during the first year of treatment and Euros 10,261.29 in subsequent years. The total 3-year cost of subcutaneous abatacept was Euros 29,953.89 per patient. Sensitivity analyses proved the model to be robust. Subcutaneous abatacept remained cost-saving in 100% of probabilistic sensitivity analysis simulations versus adalimumab, certolizumab, etanercept and golimumab, in more than 99.6% versus intravenous abatacept and tocilizumab and in 62.3% versus infliximab. CONCLUSIONS: Treatment with subcutaneous abatacept is cost-saving versus intravenous abatacept, adalimumab, certolizumab, etanercept, golimumab, infliximab and tocilizumab in the management of rheumatoid arthritis patients initiating treatment with biological antirheumatic drugs.

OBJETIVO: Comparar, desde la perspectiva del Sistema Sanitario, el coste del tratamiento con abatacept subcutáneo en pacientes con artritis reumatoide tras fracaso a metotrexato, frente al resto de fármacos antirreumáticos modificadores de la enfermedad disponibles en España con indicación en primera línea de terapia biológica. MÉTODOS: Una comparación indirecta demostró eficacia y seguridad de abatacept subcutáneo comparables a abatacept intravenoso, adalimumab, certolizumab, etanercept, golimumab, infliximab y tocilizumab, por lo que se optó por una minimización de costes. El análisis incluyó costes farmacológicos y de administración (, 2013) para un paciente "tipo" de 70 kg y un horizonte temporal de tres años. Se aplicó una tasa anual de descuento del 3%. Se realizaron análisis de sensibilidad determinísticos y probabilísticos. RESULTADOS: Abatacept subcutáneo tuvo un coste anual de 10.760,41 durante el primer año, 10.261,29 en los años siguientes, y un coste total de 29.953,89 a los tres años, generando ahorros (rango -831,41 versus infliximab a -9.741,69 versus tocilizumab) frente a los demás antirreumáticos modificadores de la enfermedad. Las mayores diferencias entre fármacos se observaron durante el primer año de tratamiento. Abatacept subcutáneo se asoció a ahorros en el 100% de las simulaciones del análisis de sensibilidad probabilístico versus adalimumab, certolizumab, etanercept y golimumab, en más del 99,6% versus abatacept intravenoso y tocilizumab y en el 62,3% versus infliximab. CONCLUSIONES: En base a los resultados, el tratamiento con abatacept subcutáneo genera ahorros frente a abatacept intravenoso, adalimumab, certolizumab, etanercept, golimumab, infliximab y tocilizumab en pacientes con artritis reumatoide que inician tratamiento con fármacos antirreumáticos biológicos.

Análisis de minimización de costes de abatacept subcutáneo en el tratamiento de la artritis reumatoide en España / Cost-minimization analysis of subcutaneous abatacept in the treatment of rheumatoid arthritis in Spain

Objetivo: Comparar, desde la perspectiva del Sistema Sanitario, el coste del tratamiento con abatacept subcutáneo en pacientes con artritis reumatoide tras fracaso a metotrexato, frente al restode fármacos antirreumáticos modificadores de la enfermedad disponibles en España con indicación en primera línea de terapia biológica. Métodos: Una comparación indirecta demostró eficacia y seguridad de abatacept subcutáneo comparables a abatacept intravenoso, adalimumab, certolizumab, etanercept, golimumab, infliximab y tocilizumab, por lo que se optó por una minimización de costes. El análisis incluyó costes farmacológicos y de administración (Euros, 2013) para un paciente "tipo" de 70 kg y un horizonte temporal de tres años. Se aplicó una tasa anual dedescuento del 3%. Se realizaron análisis de sensibilidad determinísticos y probabilísticos. Resultados: Abatacept subcutáneo tuvo un coste anual de 10.760,41 Euros durante el primer año, 10.261,29 Euros en los años siguientes, y un coste total de 29.953,89 Euros a los tres años, generando ahorros (rango -831,41 € versus infliximab a -9.741,69 € versus tocilizumab) frente a los demás antirreumáticos modificadores de la enfermedad. Las mayores diferencias entre fármacos se observaron durante el primer año de tratamiento. Abatacept subcutáneo se asoció a ahorros en el 100% de las simulaciones del análisis de sensibilidad probabilístico versus adalimumab, certolizumab, etanercept y golimumab, en más del 99,6% versus abatacept intravenoso y tocilizumab y en el 62,3% versus infliximab. Conclusiones: En base a los resultados, el tratamiento con abatacept subcutáneo genera ahorros frente a abatacept intravenoso, adalimumab, certolizumab, etanercept, golimumab, infliximab y tocilizumab en pacientes con artritis reumatoide que inician tratamiento con fármacos antirreumáticos biológicos

Objective: To compare the cost of treating rheumatoid arthritis patients that have failed an initial treatment with methotrexate, with subcutaneous aba tacept versus other first-line biologic disease-modifying antirheumatic drugs. Method: Subcutaneous abatacept was considered comparable to intravenous abatacept, adalimumab, certolizumab pegol, etanercept, golimumab,infliximab and tocilizumab, based on indirect comparison using mixed treatment analysis. A cost-minimization analysis was therefore considered appropriate. The Spanish Health System perspective and a 3 year time horizon were selected. Pharmaceutical and administration costs (Euros ,2013) of all available first-line biological disease-modifying antirheumatic drugs were considered. Administration costs were obtained from a local costs database. Patients were considered to have a weight of 70 kg. A 3%annual discount rate was applied. Deterministic and probabilistic sensitivity analyses were performed. Results: Subcutaneous abatacept proved in the base case to be less costly than all other biologic antirrheumatic drugs (ranging from € -831.42 to € -9,741.69 versus infliximab and tocilizumab, respectively). Subcutaneous abatacept was associated with a cost of € 10,760.41 per patient during the first year of treatment and €10,261.29 in subsequent years. The total 3-year cost of subcutaneous abatacept was € 29,953.89 per patient. Sensitivity analyses proved the model to be robust. Subcutaneous abatacept remained cost-saving in 100% of probabilistic sensitivity analysis simulations versus adalimumab, certolizumab, etanercept and golimumab, in more than 99.6% versus intravenous abatacept and tocilizumab and in 62.3% versus infliximab. Conclusions: Treatment with subcutaneous abatacept is cost-saving versus intravenous abatacept, adalimumab, certolizumab, etanercept, golimumab, infliximab and tocilizumab in the management of rheumatoid arthritis patients initiating treatment with biological antirheumatic drugs

[Terminology and manifestations of eruption disturbances]. / Terminologie en vormen van eruptiestoornissen.

Eruption disturbances of teeth are not unusual; many variations are encountered and eruption disturbances can negatively influence the development of the tooth and jaw system. Causes of eruption disturbances can be categorized into general and local factors. The clinical spectrum of eruption disturbances involves syndromic and non-syndromic problems for both kinds of factors, varying from delayed eruption to primary failure of eruption. The following types of eruption disturbances should be distinguished: impaction, primary retention, secondary retention and primary failure of eruption. Early detection of eruption disturbances and timely and appropriate treatment of the various eruption disturbances play an important role in preventing the negative effects of eruption disturbances on the development of the dentition and the craniofacial skeleton.

C/EBP homologous protein inhibits tissue repair in response to gut injury and is inversely regulated with chronic inflammation.

Loss of intestinal epithelial cell (IEC) homeostasis and apoptosis negatively affect intestinal barrier function. Uncontrolled activation of the unfolded protein response (UPR) in IEC contributes to an impaired barrier and is implicated in the pathogenesis of inflammatory bowel diseases. However, the contribution of the UPR target gene C/EBP homologous protein (CHOP), an apoptosis-associated transcription factor, to inflammation-related disease susceptibility remains unclear. Consistent with observations in patients with ulcerative colitis, we show that despite UPR activation in the epithelium, CHOP expression was reduced in mouse models of T-cell-mediated and bacteria-driven colitis. To elucidate the molecular mechanisms of IEC-specific CHOP expression, we generated a conditional transgenic mouse model (Chop(IEC Tg/Tg)). Chop overexpression increased the susceptibility toward dextran sodium sulfate (DSS)-induced intestinal inflammation and mucosal tissue injury. Furthermore, a delayed recovery from DSS-induced colitis and impaired closure of mechanically induced mucosal wounds was observed. Interestingly, these findings seemed to be independent of CHOP-mediated apoptosis. In vitro and in vivo cell cycle analyses rather indicated a role for CHOP in epithelial cell proliferation. In conclusion, these data show that IEC-specific overexpression impairs epithelial cell proliferation and mucosal tissue regeneration, suggesting an important role for CHOP beyond mediating apoptosis.

Could hyponatremia be a marker of anastomotic leakage after colorectal surgery? A single center analysis of 1,106 patients over 5 years.

PURPOSE: The aim of this study is to define the significance of hyponatremia as a marker of anastomotic leakage after colorectal surgery. METHODS: All anastomoses in colorectal surgery performed at a single institution between July 2007 and July 2012 (n = 1,106) were retrospectively identified. Serum sodium levels and leukocyte values measured when an anastomotic leak was diagnosed by CT scan and/or surgical reintervention (n = 81) were compared to the values preferably on postoperative day 5 in the absence of an anastomotic leak (n = 1,025). RESULTS: The leak rate in anastomoses of the rectum was 9.0 %, while the leak rate of the other anastomoses was 5.4 %. Mean serum sodium level was 138.8 mmol/l in the group with an anastomotic leak and 140.5 mmol/l in the group without. Hyponatremia (<136 mmol/l) was present in 23 % of patients in the group with an anastomotic leak and in 15 % in the group without (p < 0.001). In multivariate analysis, leukocytes and serum sodium level remained as significant markers of an anastomotic leak. As a marker of an anastomotic leak, hyponatremia had a specificity of 93 % and a sensitivity of 23 %, while the presence of either leukocytosis or hyponatremia had a sensitivity of 68 %, a specificity of 75 %, a positive predictive value of 18 %, and a negative predictive value of 97 %. CONCLUSIONS: Hyponatremia could be a specific and relevant marker of anastomotic leakage after colorectal surgery. If hyponatremia and leukocytosis are present after colorectal surgery, anastomotic leakage should be suspected and a CT scan with rectal contrast dye is recommended.

A rapid ex vivo tissue model for optimising drug detection and ionisation in MALDI imaging studies.

The aim of this study was to establish an ex vivo model for a faster optimisation of sample preparation procedures, for example matrix choice, in matrix-assisted laser desorption/ionisation (MALDI) drug imaging studies. The ionisation properties of four drugs, afatinib, erlotinib, irinotecan and pirfenidone, were determined in an ex vivo tissue experiment by spotting decreasing dilution series onto liver sections. Hereby, the drug signals were distinctly detectable using different matrix compounds, which allowed the selection of the optimal matrix for each drug. The analysis of afatinib and erlotinib yielded high drug signals with α-cyano-4-hydroxycinnamic acid matrix, whereas 2,3-dihydroxybenzoic acid was identified as optimal matrix for irinotecan and pirfenidone detection. Our method was validated by a MALDI drug imaging approach of in vivo treated mouse tissue resulting in corresponding findings, indicating the spotting method as an appropriate approach to determine the matrix of choice. The present study shows the accordance between the detection of ex vivo spotted drugs and in vivo administered drugs by MALDI-TOF and MALDI-FT-ICR imaging, which has not been demonstrated so far. Our data suggest the ex vivo tissue spotting method as an easy and reliable model to optimise MALDI imaging measurements and to predict drug detection in tissue sections derived from treated mice prior to the recruitment of laboratory animals, which helps to save animals, time and costs.

Activation of the PI3K/AKT pathway correlates with prognosis in stage II colon cancer.

BACKGROUND: Patients with UICC/AJCC stage II colon cancer have a high 5-year overall survival rate after surgery. Nevertheless, a significant subgroup of patients develops tumour recurrence. Currently, there are no clinically established biomarkers available to identify this patient group. We applied reverse-phase protein arrays (RPPA) for phosphatidylinositide-3-kinase pathway activation mapping to stratify patients according to their risk of tumour recurrence after surgery. METHODS: Full-length proteins were extracted from formalin-fixed, paraffin-embedded tissue samples of 118 patients who underwent curative resection. RPPA technology was used to analyse expression and/or phosphorylation levels of six major factors of the phosphatidylinositide-3-kinase pathway. Oncogenic mutations of KRAS and BRAF, and DNA microsatellite status, currently discussed as prognostic markers, were analysed in parallel. RESULTS: Expression of phospho-AKT (HR=3.52; P=0.032), S6RP (HR=6.3; P=0.044), and phospho-4E-BP1 (HR=4.12; P=0.011) were prognostic factors for disease-free survival. None of the molecular genetic alterations were significantly associated with prognosis. CONCLUSIONS: Our data indicate that activation of the PI3K/AKT pathway evidenced on the protein level might be a valuable prognostic marker to stratify patients for their risk of tumour recurrence. Beside adjuvant chemotherapy targeting of upregulated PI3K/AKT signalling may be an attractive strategy for treatment of high-risk patients.

A multi-center comparison of diagnostic methods for the biochemical evaluation of suspected mitochondrial disorders.

A multicenter comparison of mitochondrial respiratory chain and complex V enzyme activity tests was performed. The average reproducibility of the enzyme assays is 16% in human muscle samples. In a blinded diagnostic accuracy test in patient fibroblasts and SURF1 knock-out mouse muscle, each lab made the correct diagnosis except for two complex I results. We recommend that enzyme activities be evaluated based on ratios, e.g. with complex IV or citrate synthase activity. In spite of large variations in observed enzyme activities, we show that inter-laboratory comparison of patient sample test results is possible by using normalization against a control sample.

Enabling fiber optic serotyping of pathogenic bacteria through improved anti-fouling functional surfaces.

Significant research efforts are continually being directed towards the development of sensitive and accurate surface plasmon resonance biosensors for sequence specific DNA detection. These sensors hold great potential for applications in healthcare and diagnostics. However, the performance of these sensors in practical usage scenarios is often limited due to interference from the sample matrix. This work shows how the co-immobilization of glycol(PEG) diluents or 'back filling' of the DNA sensing layer can successfully address these problems. A novel SPR based melting assay is used for the analysis of a synthetic oligomer target as well as PCR amplified genomic DNA extracted from Legionella pneumophila. The benefits of sensing layer back filling on the assay performance are first demonstrated through melting analysis of the oligomer target and it is shown how back filling enables accurate discrimination of Legionella pneumophila serogroups directly from the PCR reaction product with complete suppression of sensor fouling.

Specific activity of cyclin-dependent kinase I is a new potential predictor of tumour recurrence in stage II colon cancer.

BACKGROUND: There are no established biomarkers to identify tumour recurrence in stage II colon cancer. As shown previously, the enzymatic activity of the cyclin-dependent kinases 1 and 2 (CDK1 and CDK2) predicts outcome in breast cancer. Therefore, we investigated whether CDK activity identifies tumour recurrence in colon cancer. METHODS: In all, 254 patients with completely resected (R0) UICC stage II colon cancer were analysed retrospectively from two independent cohorts from Munich (Germany) and Leiden (Netherlands). None of the patients received adjuvant treatment. Development of distant metastasis was observed in 27 patients (median follow-up: 86 months). Protein expression and activity of CDKs were measured on fresh-frozen tumour samples. RESULTS: Specific activity (SA) of CDK1 (CDK1SA), but not CDK2, significantly predicted distant metastasis (concordance index=0.69, 95% confidence interval (CI): 0.55-0.79, P=0.036). Cutoff derivation by maximum log-rank statistics yielded a threshold of CDK1SA at 11 (SA units, P=0.029). Accordingly, 59% of patients were classified as high-risk (CDK1SA ≥11). Cox proportional hazard analysis revealed CDK1SA as independent prognostic variable (hazard ratio=6.2, 95% CI: 1.44-26.9, P=0.012). Moreover, CKD1SA was significantly elevated in microsatellite-stable tumours. CONCLUSION: Specific activity of CDK1 is a promising biomarker for metastasis risk in stage II colon cancer.