30 research outputs found
A composite immune signature parallels disease progression across T1D subjects
At diagnosis, most people with type 1 diabetes (T1D) produce measurable levels of endogenous insulin, but the rate at which insulin secretion declines is heterogeneous. To explain this heterogeneity, we sought to identify a composite signature predictive of insulin secretion, using a collaborative assay evaluation and analysis pipeline that incorporated multiple cellular and serum measures reflecting beta cell health and immune system activity. The ability to predict decline in insulin secretion would be useful for patient stratification for clinical trial enrollment or therapeutic selection. Analytes from 12 qualified assays were measured in shared samples from subjects newly diagnosed with T1D. We developed a computational tool to identify a composite panel associated with decline in insulin secretion over 2 years after diagnosis. The tool employs multiple filtering steps to reduce data dimensionality, incorporates error-estimation techniques including cross-validation and sensitivity analysis, and is flexible to assay type, clinical outcome and disease setting. Using this novel analytical tool, we identified a panel of immune markers that, in combination, are highly associated with loss of insulin secretion. The methods used here represent a novel process for identifying combined immune signatures that predict outcomes relevant for complex and heterogeneous diseases like T1D
Expression Signatures of Metastatic Capacity in a Genetic Mouse Model of Lung Adenocarcinoma
Background: Non-small cell lung cancer (NSCLC) is the foremost cause of cancer-related death in Western countries, which is due partly to the propensity of NSCLC cells to metastasize. The biologic basis for NSCLC metastasis is not well understood. Methodology/Principal Findings: Here we addressed this deficiency by transcriptionally profiling tumors from a genetic mouse model of human lung adenocarcinoma that develops metastatic disease owing to the expression of K-rasG12D and p53R172H. We identified 2,209 genes that were differentially expressed in distant metastases relative to matched lung tumors. Mining of publicly available data bases revealed this expression signature in a subset of NSCLC patients who had a poorer prognosis than those without the signature. Conclusions/Significance: These findings provide evidence that K-rasG12D; p53R172H mice recapitulate features of human NSCLC metastasis and will provide a useful platform on which to study the biologic basis for lung adenocarcinom
Effect of methionine sulfoximine on methylation of guanine residues in astroglial transfer ribonucleic acids
Culture-grown astrocytes derived from 3-day-old rat brain were incubated in the presence of [ 3 H]guanosine and of the convulsant agent l -methionine- dl -sulfoximine (MSO). The resulting [ 3 H]tRNA was purified from control and MSO-exposed cells at several time points during the incubation and was hydrolyzed to [ 3 H]guanine and four [ 3 H]methyl guanines which were separated by high pressure liquid chromatography. Three of the four [ 3 H]methyl guanines were more highly labeled in the [ 3 H]tRNA of the MSO-exposed cells, relative to that of the control cells throughout the entire incubation period. The findings extend to cultured astrocytes, the stimulatory effect of MSO on the methylation of neural tRNA guanines, previouly observed both in vitro using [ 14 C] S -adenosyl- l -methionine and in vivo using [ methyl 3 -H] l -methionine.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45427/1/11064_2004_Article_BF00964832.pd
Recommended from our members
Actions of Similar Others as Inducements to Cooperate in Social Dilemmas
Two studies were conducted to determine whether information about the actions of others in a multitrial social dilemma can influence choice behavior. Participants read about three (fictitious) people who supposedly had already participated in the study and who were either similar or dissimilar to a typical college student. Participants then played several trials of a social dilemma game. Study 1, which used a prisoner’s dilemma, showed that participant rates of cooperation conformed to those reported for similar, but not dissimilar, others. Study 2 added outcome information to the person descriptions and changed the game to a public goods dilemma. Cooperation rates were directly influenced by similar others when others’ choices were described as having produced large outcomes; when choices were said to have produced small outcomes, rate of cooperation was inversely related to others’ behavior. As with Study 1, information about dissimilar others had no effect on choice behavior
Markers of intestinal inflammation in patients with ankylosing spondylitis: a pilot study
Abstract Introduction Inflammatory bowel disease (IBD) and ankylosing spondylitis (AS) are similar chronic inflammatory diseases whose definitive etiology is unknown. Following recent clinical and genetic evidence supporting an intertwined pathogenic relationship, we conducted a pilot study to measure fecal calprotectin (fCAL) and IBD-related serologies in AS patients. Methods Consecutive AS patients were recruited from a long-term prospectively collected longitudinal AS cohort at Cedars-Sinai Medical Center. Controls were recruited from Cedars-Sinai Medical Center employees or spouses of patients with AS. Sera were tested by ELISA for IBD-associated serologies (antineutrophil cytoplasmic antibodies (ANCA), anti-Saccharomyces cerevisiae antibody IgG and IgA, anti-I2, anti-OmpC, and anti-CBir1). The Bath Ankylosing Spondylitis Disease Activity Index, the Bath Ankylosing Spondylitis Functional Index, and the Bath Ankylosing Spondylitis Radiology Index were completed for AS patients. Results A total of 81 subjects (39 AS patients and 42 controls) were included for analysis. The average age of AS patients was 47 years and the average disease duration was 22 years. AS patients were predominantly male; 76% were HLA-B27-positive. Median fCAL levels were 42 μg/g and 17 μg/g in the AS group and controls, respectively (P < 0.001). When using the manufacturer's recommended cutoff value for positivity of 50 μg/g, stool samples of 41% of AS patients and 10% of controls were positive for fCAL (P = 0.0016). With the exception of ANCA, there were no significant differences in antibody levels between patients and controls. Median ANCA was 6.9 ELISA units in AS patients and 4.3 ELISA units in the controls. Among AS patients stratified by fCAL level, there were statistically significant differences between patients and controls for multiple IBD-associated antibodies. Conclusion Calprotectin levels were elevated in 41% of patients with AS with a cutoff value for positivity of 50 μg/g. fCAL-positive AS patients displayed higher medians of most IBD-specific antibodies when compared with healthy controls or fCAL-negative AS patients. Further studies are needed to determine whether fCAL can be used to identify and characterize a subgroup of AS patients whose disease might be driven by subclinical bowel inflammation
Tumour cell survival mechanisms in lethal metastatic prostate cancer differ between bone and soft tissue metastases
The complexity of survival mechanisms in cancer cells from patients remains poorly understood. To obtain a comprehensive picture of tumor cell survival in prostate cancer metastases, we interrogated 5 survival proteins that operate within 3 survival pathways in a cohort of 185 lethal metastatic prostate metastases obtained from 44 patients. The expression levels of BCL-2, BCL-XL, MCL-1, cytoplasmic Survivin, nuclear Survivin, and Stathmin were measured by immunohistochemistry in a tissue microarray. Simultaneous expression of 3 or more proteins occured in 81% of lethal prostate cancer metastasis and BCL-2, cytoplasmic Survivin and MCL-1 were co-expressed in 71% of metastatic sites. An unsupervised cluster analysis separated bone and soft tissue metastases according to patterns of survival protein expression. BCL-2, cytoplasmic Survivin and MCL-1 had significantly higher expression in bone metastases (p < 10(−5)), while nuclear Survivin was significantly higher in soft tissue metastases (p = 3×10(−14)). BCL-XL overexpression in soft tissue metastases almost reached significance (p =0.09), while stathmin expression did not (p=0.28). In addition, the expression of MCL-1 was significantly higher in AR-positive tumors. Neuroendocrine differentiation was not associated with specific survival pathways. These studies demonstrate for the first time that bone and soft tissue metastases from the same patient differ significantly in expression of a panel of survival proteins and that with regards to survival protein expression, expression is associated with metastatic site and not patient. Altogether this study suggests that optimal therapeutic inhibition may require combinations of drugs that target both bone as well as soft tissue-specific survival pathways
