Mark H. Wener

Elevated Biomarkers of Inflammation Are Associated With Reduced Survival Among Breast Cancer Patients

PURPOSE Chronic inflammation is believed to contribute to the development and progression of breast cancer. Systemic C-reactive protein (CRP) and serum amyloid A (SAA) are measures of low-grade chronic inflammation and potential predictors of cancer survival. PATIENTS AND METHODS We evaluated the relationship between circulating markers of inflammation and breast cancer survival using data from the Health, Eating, Activity, and Lifestyle (HEAL) Study (a multiethnic prospective cohort study of women diagnosed with stage 0 to IIIA breast cancer). Circulating concentrations of CRP and SAA were measured approximately 31 months after diagnosis and tested for associations with disease-free survival (approximately 4.1 years of follow-up) and overall survival (approximately 6.9 years of follow-up) in 734 disease-free breast cancer survivors. Cox proportional hazards models were used with adjustment for potential confounding factors to generate hazard ratios (HRs) and 95% CIs. Results Elevated SAA and CRP were associated with reduced overall survival, regardless of adjustment for age, tumor stage, race, and body mass index (SAA P trend < .0001; CRP P trend = .002). The HRs for SAA and CRP tertiles suggested a threshold effect on survival, rather than a dose-response relationship (highest v lowest tertile: SAA HR = 3.15; 95% CI, 1.73 to 5.65; CRP HR = 2.27; 95% CI, 1.27 to 4.08). Associations were similar and still significant after adjusting for self-reported history of cardiovascular events and censoring cardiovascular disease deaths. Elevated CRP and SAA were also associated with reduced disease-free survival, although these associations were of borderline significance (SAA P trend = .04; CRP P trend = .07). CONCLUSION Circulating SAA and CRP may be important prognostic markers for long-term survival in breast cancer patients, independent of race, tumor stage, and body mass index.

A Genomewide Screen in Multiplex Rheumatoid Arthritis Families Suggests Genetic Overlap with Other Autoimmune Diseases

Rheumatoid arthritis (RA) is an autoimmune/inflammatory disorder with a complex genetic component. We report the first major genomewide screen of multiplex families with RA gathered in the United States. The North American Rheumatoid Arthritis Consortium, using well-defined clinical criteria, has collected 257 families containing 301 affected sibling pairs with RA. A genome screen for allele sharing was performed, using 379 microsatellite markers. A nonparametric analysis using SIBPAL confirmed linkage of the HLA locus to RA (P < .00005), with lambdaHLA = 1.79. However, the analysis also revealed a number of non-HLA loci on chromosomes 1 (D1S235), 4 (D4S1647), 12 (D12S373), 16 (D16S403), and 17 (D17S1301), with evidence for linkage at a significance level of P<.005. Analysis of X-linked markers using the MLOD method from ASPEX also suggests linkage to the telomeric marker DXS6807. Stratifying the families into white or seropositive subgroups revealed some additional markers that showed improvement in significance over the full data set. Several of the regions that showed evidence for nominal significance (P < .05) in our data set had previously been implicated in RA (D16S516 and D17S1301) or in other diseases of an autoimmune nature, including systemic lupus erythematosus (D1S235), inflammatory bowel disease (D4S1647, D5S1462, and D16S516), multiple sclerosis (D12S1052), and ankylosing spondylitis (D16S516). Therefore, genes in the HLA complex play a major role in RA susceptibility, but several other regions also contribute significantly to overall genetic risk.

The fundamental flaws of immunoassays and potential solutions using tandem mass spectrometry.

Immunoassays have made it possible to measure dozens of individual proteins and other analytes in human samples for help in establishing the diagnosis and prognosis of disease. In too many cases the results of those measurements are misleading and can lead to unnecessary treatment or missed opportunities for therapeutic interventions. These cases stem from problems inherent to immunoassays performed with human samples, which include a lack of concordance across platforms, autoantibodies, anti-reagent antibodies, and the high-dose hook effect. Tandem mass spectrometry may represent a detection method capable of alleviating many of the flaws inherent to immunoassays. We review our understanding of the problems associated with immunoassays on human specimens and describe methodologies using tandem mass spectrometry that could solve some of those problems. We also provide a critical discussion of the potential pitfalls of novel mass spectrometric approaches in the clinical laboratory.

Quantification of Thyroglobulin, a Low-Abundance Serum Protein, by Immunoaffinity Peptide Enrichment and Tandem Mass Spectrometry

BACKGROUND Quantification of serum tumor markers plays an important role in determining whether patients treated for cancer require further therapy. Whereas large-scale proteomic efforts aim to identify novel tumor markers to facilitate early detection, optimization of methods for quantifying known tumor markers offers another approach to improving management of malignancies. For example, immunoassays used in clinical practice to measure established tumor markers suffer from potential interference from endogenous immunoglobulins and imperfect concordance across platforms-problems that also plague many other immunoassays. To address these important limitations, this study used peptide immunoaffinity enrichment in concert with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to quantify thyroglobulin, a well-characterized tumor marker. METHODS We identified 3 peptides in tryptic digests of thyroglobulin that were detected at low concentrations by tandem mass spectrometry, raised polyclonal antibodies to those peptides, and used the antibodies to extract the 3 corresponding peptides from tryptic digests of human serum. We quantified each endogenous peptide using LC-MS/MS and multiple reaction monitoring with external calibrators. RESULTS The detection limit for endogenous thyroglobulin in serum was 2.6 microg/L (4 pmol/L). Direct comparison with immunoassay revealed good correlation (r(2) = 0.81). CONCLUSIONS Immunoaffinity peptide enrichment-tandem mass spectrometry can detect tryptic peptides of thyroglobulin at picomolar concentrations while also digesting the endogenous immunoglobulins that can potentially interfere with traditional immunoassays. Our observations suggest a general analytical strategy for using immunoaffinity isolation together with tandem mass spectrometry to quantify tumor antigens and other low-abundance proteins in human serum.

Neuropsychiatric lupus erythematosus: A 10-year prospective study on the value of diagnostic tests

PURPOSE To evaluate which serologic, cerebrospinal fluid (CSF), and neuroradiographic tests alone or in combination are most useful in the diagnosis of neuropsychiatric lupus erythematosus (NPLE). PATIENTS AND METHODS Prospective study of patients with systemic lupus erythematosus (SLE) hospitalized with neuropsychiatric disease between January 1982 and December 1991. Special tests evaluated as part of this study included serum antinuclear antibodies, complement levels, serum and CSF antineuronal antibodies, CSF special protein studies (immunoglobulin G [IgG] index and oligoclonal bands), serum antiribosomal-P antibodies, serum antiphospholipid antibodies, and cranial magnetic resonance imaging (MRI). Diagnostic sensitivity, specificity, and positive predictive value (PPV) were determined for single tests and combinations of tests. RESULTS Fifty-two NPLE patients were categorized by neuropsychiatric presentation (32 diffuse, 10 focal, and 10 complex presentations) and compared to 14 SLE control patients. Each NPLE patient with a diffuse or complex presentation had abnormal CSF IgG index/oligoclonal bands, elevated CSF antineuronal antibodies, and/or serum antiribosomal-P antibodies, yielding a sensitivity of 100%, specificity of 86%, and PPV of 95% for this combination of tests. Nine of 10 patients with focal presentations and all with complex disease had evidence of vasculitis/livedo reticularis, antiphospholipid antibodies, and/or a cranial MRI with multiple lesions, giving a sensitivity of 95%, specificity of 86%, and a PPV of 90% for this battery of tests. These combinations of tests correctly diagnosed all nine SLE patients whose initial diagnosis proved to be incorrect based on subsequent clinical course. Abnormal test results frequently normalized or improved with successful therapy. CONCLUSIONS Specific tests for CSF antibodies are most useful diagnostically in diffuse NPLE, implicating autoantibodies in the pathogenesis of this NPLE presentation. In those patients with diffuse NPLE who present with primarily psychiatric disease, serum antiribosomal-P antibodies appear to be helpful. In contrast, focal NPLE appears to be mostly secondary to vascular occlusion, and the presence of dermal vasculitis/livedo reticularis, antiphospholipid antibodies, and/or an abnormal cranial MRI are most helpful diagnostically. Patients with complex presentations demonstrate abnormalities characteristic of both diffuse and focal NPLE. Abnormal tests can be followed serially and appear to correlate with clinical responses to therapy.

Adipokines, inflammation, and visceral adiposity across the menopausal transition: a prospective study.

CONTEXT Postmenopausal women have greater visceral adiposity compared with premenopausal women. Adipokines are associated with increased adiposity, insulin resistance, and atherosclerosis. OBJECTIVE The objective of the study was to assess changes in adipokines and inflammatory markers through the menopausal transition and correlate them with changes in visceral adiposity. DESIGN AND SETTING This was a prospective cohort study of women through the menopausal transition conducted at the University of Washington. PARTICIPANTS Sixty-nine healthy women were followed up longitudinally from premenopausal (aged 45-55 yr) to postmenopausal status (aged 49-60 yr). OUTCOME On premenopausal and postmenopausal visits, fasting blood was drawn for adiponectin, leptin, serum amyloid A (SAA), C-reactive protein (CRP), monocyte-chemotactic protein-1, tissue plasminogen activator antigen (tPA), IL-6, and TNF-alpha. Body composition measures were assessed by body mass index, whole-body dual x-ray absorptiometry scan, and computed tomography scan of the abdomen at the lumbar 4-5 level. RESULTS Women had a statistically significant increase in SAA, tPA, monocyte-chemotactic protein-1, and adiponectin between the two measurement occasions (P = 0.04, P = 0.02, P = 0.001, and P < 0.001, respectively). The increase in intraabdominal fat was correlated positively with the change in SAA (r = 0.31, P = 0.02), CRP (r = 0.56, P < 0.001), tPA (r = 0.40, P = 0.002), and leptin (r = 0.41, P = 0.002) and negatively correlated with the change in adiponectin (r = -0.37, P = 0.005). After adjustment for change in sc abdominal fat, the correlation between change in CRP, tPA, leptin, and adiponectin remained significantly associated with change in intraabdominal fat. CONCLUSIONS Women going through the menopausal transition have deleterious changes in inflammatory markers and adipokines that correlate with increased visceral adiposity.

Effects of a caloric restriction weight loss diet and exercise on inflammatory biomarkers in overweight/obese postmenopausal women: a randomized controlled trial.

Obese and sedentary persons have increased risk for cancer; inflammation is a hypothesized mechanism. We examined the effects of a caloric restriction weight loss diet and exercise on inflammatory biomarkers in 439 women. Overweight and obese postmenopausal women were randomized to 1-year: caloric restriction diet (goal of 10% weight loss, N = 118), aerobic exercise (225 min/wk of moderate-to-vigorous activity, N = 117), combined diet + exercise (N = 117), or control (N = 87). Baseline and 1-year high-sensitivity C-reactive protein (hs-CRP), serum amyloid A (SAA), interleukin-6 (IL-6), leukocyte, and neutrophil levels were measured by investigators blind to group. Inflammatory biomarker changes were compared using generalized estimating equations. Models were adjusted for baseline body mass index (BMI), race/ethnicity, and age. Four hundred and thirty-eight (N = 1 in diet + exercise group was excluded) were analyzed. Relative to controls, hs-CRP decreased by geometric mean (95% confidence interval, P value): 0.92 mg/L (0.53-1.31, P < 0.001) in the diet and 0.87 mg/L (0.51-1.23, P < 0.0001) in the diet + exercise groups. IL-6 decreased by 0.34 pg/mL (0.13-0.55, P = 0.001) in the diet and 0.32 pg/mL (0.15-0.49, P < 0.001) in the diet + exercise groups. Neutrophil counts decreased by 0.31 × 10(9)/L (0.09-0.54, P = 0.006) in the diet and 0.30 × 10(9)/L (0.09-0.50, P = 0.005) in the diet + exercise groups. Diet and diet + exercise participants with 5% or more weight loss reduced inflammatory biomarkers (hs-CRP, SAA, and IL-6) compared with controls. The diet and diet + exercise groups reduced hs-CRP in all subgroups of baseline BMI, waist circumference, CRP level, and fasting glucose. Our findings indicate that a caloric restriction weight loss diet with or without exercise reduces biomarkers of inflammation in postmenopausal women, with potential clinical significance for cancer risk reduction.

Obesity Is Negatively Associated with Prostate-Specific Antigen in U.S. Men, 2001-2004

Background: Recent studies have shown a negative association between body mass index (BMI) and prostate-specific antigen (PSA), a commonly used serum marker for the detection and diagnosis of prostate cancer. We have examined the association between several anthropometric measures and PSA in a nationally representative sample of men. Methods: We analyzed data from the 2001-2004 National Health and Nutrition Examination Survey. Participants in this study were men ages ≥40 years without previously diagnosed prostate cancer who had PSA measured. Height, weight, waist circumference, BMI, triceps skinfold, subscapular skinfold, and calculated total body water were examined categorically by quintiles using multiple linear regression models. All tests of significance were two sided. Results: Among white men, we report a trend for decreasing PSA with increasing weight, BMI, waist circumference, triceps skinfold thickness, and calculated total body water. Among Mexican American men, we found a trend for decreasing PSA with increasing BMI, and among black men we found a trend for decreasing PSA with increasing triceps thickness. None of the interaction terms between race/ethnicity and any of the anthropometric measures were statistically significant. Controlling for age and race/ethnicity in the multiple linear regression model, we found moderate declines in PSA with a 1 SD increase in BMI [5.9% decrease (95% confidence interval, −9.0% to −2.8%) in geometric mean PSA per 5.2-unit increase], weight [5.9% decline (−8.8% to −2.8%) per 17.7-kg increase], waist circumference [6.6% decline (−9.4% to −3.6%) per 13.4-cm increase], triceps skinfold [5.4% decline (−8.9% to −1.8%) per 6.4-mm increase], and calculated total body water [5.7% decline (−8.9% to −2.4%) per 6.5-liter increase]. Conclusion: Our population-based, nationally representative results expand the validity of previous studies on obesity and PSA. Higher weight, BMI, waist circumference, triceps skinfold, and total body water are associated with moderately lower PSA values. A prospective study is needed to verify whether this association affects the accuracy of the PSA test in obese men. (Cancer Epidemiol Biomarkers Prev 2007;16(1):70–6)

High-density SNP analysis of 642 Caucasian families with rheumatoid arthritis identifies two new linkage regions on 11p12 and 2q33

We have completed a genome wide linkage scan using >5700 informative single-nucleotide polymorphism (SNP) markers (Illumina IV SNP linkage panel) in 642 Caucasian families containing affected sibling pairs with rheumatoid arthritis (RA), ascertained by the North American Rheumatoid Arthritis Consortium. The results show striking new evidence of linkage at chromosomes 2q33 and 11p12 with logarithm of odds (LOD) scores of 3.52 and 3.09, respectively. In addition to a strong and broad linkage interval surrounding the major histocompatibility complex (LOD>16), regions with LOD>2.5 were observed on chromosomes 5 and 10. Additional linkage evidence (LOD scores between 1.46 and 2.35) was also observed on chromosomes 4, 7, 12, 16 and 18. This new evidence for multiple regions of genetic linkage is partly explained by the significantly increased information content of the Illumina IV SNP linkage panel (75.6%) compared with a standard microsatellite linkage panel utilized previously (mean 52.6%). Stratified analyses according to whether or not the sibling pair members showed elevated anticyclic citrullinated peptide titers indicates significant variation in evidence for linkage among strata on chromosomes 4, 5, 6 and 7. Overall, these new linkage data should reinvigorate efforts to utilize positional information to identify susceptibility genes for RA.

Screening for Prostatic Carcinoma with Prostate Specific Antigen: Results of the Second Year

Prostate specific antigen (PSA) has been shown to be useful alone and in conjunction with other tests in the diagnosis of prostatic carcinoma. Previously, we demonstrated that a PSA level of greater than 4.0 ng./ml. as the initial diagnostic test in a screening population results in a detection rate of 2.6 and positive predictive value of 30.5. In the present investigation we performed digital rectal examination and transrectal ultrasound as well as ultrasound guided biopsy in men who in the initial year of the screening study had a PSA level of less than 4.0 ng./ml. but on evaluation 1 year later they had a 20% increase in the PSA level. A total of 701 subjects returned for year 2 of the protocol and 260 (37.1%) demonstrated more than a 20% increase in PSA value. Biopsy was performed in 82 men and carcinoma was detected in 14 (17.1%). Of the men with carcinoma 12 had a second year PSA level of less than 4.0 ng./ml. Radical prostatectomy was performed in 8 patients, 7 of whom had organ confined disease or tumor penetrating the capsule with negative margins. We conclude that a 20% annual change in PSA level may identify men at significant risk for prostatic carcinoma and that patients so identified have favorable pathological stage.