Predictive potential of various plasma inflammation-, angiogenesis-, and extracellular matrix remodeling-associated mediators for intra-amniotic inflammation and/or microbial invasion of the amniotic cavity in preterm labor.

PURPOSE: To determine whether various inflammatory-, angiogenic/anti-angiogenic-, and extracellular matrix remodeling-associated proteins in plasma, alone or in combination with conventional blood-based markers, can predict intra-amniotic inflammation and/or microbial invasion of the amniotic cavity (IAI/MIAC) in women with spontaneous preterm labor (PTL). METHODS: A total of 193 singleton pregnant women with PTL (23-33 weeks) were included in this retrospective cohort study. Plasma samples were obtained at the time of amniocentesis. Amniotic fluid (AF) was cultured for microorganism detection and consequent MIAC diagnosis. IL-6 levels were determined in AF and used to identify IAI (AF IL-6 ≥ 2.6 ng/mL). Endostatin, haptoglobin, IGFBP-2/3, LBP, M-CSF, MMP-2/8, pentraxin 3, PlGF, S100A8/A9, and VEGFR-1 levels were assayed in plasma samples by ELISA. CRP levels and neutrophil-to-lymphocyte ratio (NLR) were measured. RESULTS: Plasma LBP, MMP-8, and S100A8/A9 levels, CRP levels, and NLR were significantly higher, and plasma IGFBP-2 and MMP-2 levels were significantly lower in women with IAI/MIAC than in those without this condition, whereas no baseline variables differed significantly between the two groups. Using a stepwise regression analysis, a noninvasive prediction model for IAI/MIAC was developed, which included plasma LBP, MMP-2, and MMP-8 levels (area under the curve [AUC], 0.785). The AUC for this prediction model was significantly or borderline greater than that of any single factor included in the model. CONCLUSIONS: IGFBP-2, LBP, MMP-2, MMP-8, and S100A8/A9 may represent valuable plasma biomarkers for predicting IAI/MIAC in women with PTL. Combination of LBP, MMP-2, and MMP-8 expression data can significantly improve the predictive potential for IAI/MIAC.

IGFBP2 function as a novel biomarker for active lupus nephritis.

In search for new targets for the diagnosis and treatment of lupus nephritis (LN), we employed TMT-liquid chromatography-triple quadrupole mass spectrometry (TMT-LC-MS/MS) combined with RNA-seq and identified a panel of proteins that was dysregulated both at protein level and mRNA level in active LN patients compared with healthy controls. We chose to study the role of IGFBP2 since it is a relatively understudied protein in the context of LN. We further validated that IGFBP2 significantly increased and correlated with SLE activity index in active LN patients. The receiver operator characteristic (ROC) curve suggested that plasma IGFBP2 had a high diagnostic efficiency for distinguishing between inactive and active LN patients (AUC = 0.992; 95% CI = 0.974-1.000; P < 0.001). We demonstrated neutralizing IGFBP2-downregulated CD4+ T cell activation, upregulated the ratio of Treg, downregulated AKT/mTOR/4E-BP1 pathway, and significantly improved nephritis in MRL/lpr mice. In all, our work demonstrated IGFBP2 as a biomarker specific for active LN and blocking IGFBP2 could be a new target for treating LN. KEY MESSAGES : Plasma IGFBP2 is a promising diagnostic marker for distinguishing stable LN from active LN, and it is also a predictor for the poor prognosis of LN. Blockade of IGFBP2 can significantly improve the pathological damage of LN. IGFBP2 may regulate activation of CD4+ T and Treg ratio. Neutralizing IGFBP2 downregulates AKT/mTOR/4E-BP1 pathway.

IGFBP-1 and IGFBP-2 are associated with a decreased pulse-wave velocity in young, healthy adults.

BACKGROUND AND AIMS: In healthy, young adults we analyzed a panel of cardiovascular disease related proteins in plasma and compared them with the vascular health of the subjects. The aim was to identify proteins with a relationship to the early atherosclerotic process in healthy individuals. METHODS: We employed the proximity extension assay from OLINK proteomics to analyze 92 cardiovascular disease (CVD) related proteins on 833 subjects (men and women, ages 18-26). The women were further divided into an estrogen-using group and non-users. Protein expression was analyzed using principal component analysis (PCA). The following vascular examinations were performed: Pulse-wave velocity (PWV), augmentation index (AIX), carotid-intima media thickness (cIMT). RESULTS: Three principal components were obtained using PCA to analyze the protein expression. None of the obtained principal components correlated significantly with AIX or cIMT. One of the components, explaining 6% of the total variance of the data, was significantly correlated with PWV. Upon examination of the proteins with the highest factor loadings on this component independently in a multivariable model, adjusting for established CVD risk biomarkers, insulin-like growth factor-binding protein 1 (IGFBP-1) and insulin-like growth factor-binding protein 2 (IGFBP-2) were found to independently, negatively correlate with PWV. Among the established risk factors included in the multivariable model, age was significantly and adversely correlated with all vascular measurements. CONCLUSIONS: In this population of healthy, young adults, groups of CVD related proteins correlate with PWV, but not AIX or cIMT. This group of proteins, of which IGFBP-1 and IGFBP-2 were independently, negatively correlated in a multivariable model with PWV, could have benificial effects on vascular stiffness. The robust association between age and PWV, AIX and cIMT provide insight into the impact of aging on the vasculature, which is detectable even in a population of young, healthy, non-smoking individuals of ages spanning only 8 years.

Serum insulin-like growth factor-binding protein 2 levels as an indicator for disease severity in enterohemorrhagic Escherichia coli induced hemolytic uremic syndrome.

BACKGROUND: Insulin-like growth factor-binding protein (IGFBP) 2 plays an important role in the regulation of cell adhesion, migration, growth, and apoptosis. This study aimed to investigate the clinical significance of serum IGFBP2 as a biomarker for disease activity and severity in hemolytic uremic syndrome (HUS) induced by enterohemorrhagic Escherichia coli (EHEC). METHODS: IGFBP2 production by human renal glomerular endothelial cells (RGECs) after exposure to Shiga toxin 2 (Stx-2) was investigated in vitro. Serum IGFBP2 levels in blood samples obtained from 22 patients with HUS and 10 healthy controls (HCs) were quantified using an enzyme-linked immunosorbent assay. The results were compared to the clinical features of HUS and serum tau and cytokine levels. RESULTS: Stx-2 induced the production of IGFBP2 in RGECs in a dose-dependent manner. Serum IGFBP2 levels were significantly higher in patients with HUS than in HCs and correlated with disease severity. Additionally, serum IGFBP2 levels were significantly higher in patients with encephalopathy than in those without encephalopathy. A serum IGFBP2 level above 3585 pg/mL was associated with a high risk of encephalopathy. Furthermore, serum IGFBP2 levels significantly correlated with serum levels of tau and inflammatory cytokines associated with the development of HUS. CONCLUSIONS: Correlation of serum IGFBP2 level with disease activity in patients with HUS suggests that IGFBP2 may be considered as a possible indicator for disease activity and severity in HUS. Larger studies and additional experiments using various cells in central nervous system should elucidate the true value of IGFBP2 as a clinical diagnostic marker. ABBREVIATIONS: IGFBP: insulin-like growth factor-binding protein; HUS: hemolytic uremic syndrome; EHEC: enterohemorrhagic Escherichia coli; RGECs: renal glomerular endothelial cells; STx-2: Shiga toxin 2; HCs: healthy controls; LPS: lipopolysaccharide; ROC: receiver operating characteristic; sTNFR: soluble tumor necrosis factor receptor.

Diagnostic accuracy of serum insulin-like growth factor-binding protein 2 for ovarian cancer.

INTRODUCTION: Insulin-like growth factor-binding protein 2 (IGFBP2) plays an important role in the pathogenesis of ovarian cancer. The most prominent effects of IGFBP2 include promoting proliferation, driving invasion, and suppressing apoptosis. This study aimed to determine the diagnostic accuracy of serum IGFBP2 in differentiating between benign and malignant ovarian neoplasms. METHODS: Preoperative serum IGFBP2 level was evaluated from 76 women with primary ovarian tumor who underwent exploratory laparotomy at Sanglah General Hospital, Denpasar, Bali, Indonesia. The optimal threshold value of IGFBP2 for the diagnosis of ovarian cancer was determined from the receiver 0perating characteristic (ROC) curve. The diagnosis was confirmed by histopathologic analysis of resected ovarian specimens. RESULTS: Forty-six (60.5%) patients were diagnosed with ovarian cancer. The area under the ROC curve (AUC) of IGFBP2 in detecting ovarian cancer was 0.815 (95% CI: 0.721 to 0.910, P<0.001). For a given specificity larger than 95%, the optimal sensitivity was 63%. The optimal threshold value of IGFBP2 for the diagnosis of ovarian cancer was 804 ng/mL [sensitivity 63%, specificity 96.7%, positive predictive value (PPV) 96.7%, negative predictive value (NPV) 63%, accuracy 76.3%, and diagnostic odd ratio (DOR) 49.5 (95% CI 6.1 to 396.5)]. In a subgroup analysis, IGFBP2 showed excellence performance in diagnosing advanced ovarian cancer (AUC 0.904 [95% CI: 0.806 to 1.000], sensitivity 83.3%, specificity 96.7%, PPV 95.2%, NPV 87.9%, accuracy 90.7%, and DOR 145.0 [95% CI 15.0 to 1395.3]). CONCLUSION: IGFBP2 is a novel and potentially promising biomarker for detecting ovarian cancer. Further studies are needed to confirm its diagnostic performance in premenopausal women and for detecting early stage ovarian cancer.

Serum IGFBP2 Level Is a New Candidate Biomarker of Severe Malnutrition in Advanced Lung Cancer.

Objectives: This study aimed to analyze and evaluate serum insulin-like growth factor-binding protein 2 (IGFBP2) levels as a new biomarker of severe malnutrition in patients with advanced lung cancer.Design and methods: This prospective study involved 59 patients with advanced lung cancer. We detected serum IGFBP2 level by using enzyme-linked immunosorbent assay and analyzed its relationship to clinical characteristics, nutritional status, Glasgow prognostic score (GPS), and survival. Serum albumin and C-reactive protein (CRP) levels were measured, and nutritional status was assessed using Patient-Generated Subjective Global Assessment (PG-SGA). The best cutoff point value for serum IGFBP2 level was established using receiver operating characteristic analysis. Kaplan-Meier method was utilized to analyze the survival curves.Results: Serum IGFBP2 levels were elevated in patients with advanced lung cancer and severe malnutrition. The best cutoff value for serum IGFBP2 level was determined at 363 ng/ml, which could diagnose severe malnutrition with 73.3% sensitivity and 70.5% specificity and was found to be related to albumin, CRP, and GPS. Patients whose serum IGFBP2 levels were higher than 363 ng/ml had poor survival outcome.Conclusion: This study demonstrates the remarkably association between higher serum level of IGFBP2 and severe malnutrition, albumin, CRP, GPS, and survival. Hence, serum IGFBP2 level can be used as a potential biomarker for diagnosis of severe malnutrition in patients with advanced lung cancer.

Differential production of insulin-like growth factor-binding proteins in liver fibrosis progression.

Noninvasive methods for liver disease diagnoses offer great advantages over biopsy, but they cannot be utilized in all cases. Therefore, specific indicators for chronic liver disease management are necessary. The aim was to assess the production of insulin-like growth factor-binding proteins (IGFBPs) 1-7 and their correlation with the different stages of fibrosis in chronic hepatitis C (CHC). A prospective, cross-sectional, multicenter study was conducted. CHC patients were categorized by FibroTest® and/or FibroScan®. Serum concentrations of IGFBPs 1-7 were determined through multiple suspension arrangement array technology. Significant differences were validated by the Kruskal-Wallis and Mann-Whitney U tests. Logistic regression models were performed to assess the association between the IGFBPs and fibrosis stages. The association was determined utilizing odds ratios (ORs), and receiver operating characteristic (ROC) curves were constructed to distinguish the IGFBPs in relation to the diagnosis of fibrosis. IGFBP-1 and IGFBP-7 concentrations were higher in CHC than in the healthy individuals, whereas IGFBP-3, IGFBP-5, and IGFBP-6 were downregulated in the patients. An apparent increase of all the IGFBPs was found at fibrosis stage F4, but with different regulations. IGFBP-2, -4, -6, and -7 had the best OR, showing the relation to fibrosis progression. The ROC curves showed that IGFBP-7 was the only protein that distinguished F1 from F3 and F2 from F3. IGFBPs participate in liver fibrosis progression and could be employed as circulating novel protein panels for diagnosis and as possible therapeutic targets in liver fibrosis progression.

Development of a novel assay for IGFBP-2 complexed with IGF-I and-II in human serum.

BACKGROUND: Insulin-like growth factor binding-protein 2 (IGFBP-2) was originally identified as an IGF-carrier, governing IGF half-life, tissue accessibility and biological effects. Later, IGFBP-2 was discovered to possess IGF-independent effects. IGFBP-2 circulates in several forms, as free protein, complexed with IGF-I or IGF-II, or as IGFBP-2 fragments. The various IGFBP-2 forms are all included when measuring serum IGFBP-2 concentrations by immunoassay (i.e., immunoreactive (ir-)IGFBP-2). In this study, we describe a novel method to measure the amount of IGF that circulates bound to IGFBP-2. METHOD: IGFBP-2 was immunoprecipitated from human serum using magnetic beads, which were subsequently eluted by acidification. After neutralization, eluates were assayed for ir-IGFBP-2, IGF-I and IGF-II and compared to serum concentrations. This allowed measurement of IGFBP-2-compexed IGF-I and IGF-II, respectively. To test the method clinically, serum from 146 patients with lung cancer, 151 patients with non-cancer pulmonary diseases and 28 healthy controls were analyzed. RESULTS: We immuno-precipitated 97 ± 3.3% of serum IGFBP-2 and recovered > 75% of IGFBP-2-complexed IGFs, with intra- and inter-assay coefficient of variations (CVs) averaging < 5% and < 13%, respectively. No co-precipitation with IGFBP-1, -3 or - 4 was detected. Serum levels of ir-IGFBP-2 (median [25;75%]) differed between groups (cancer patients vs. non-cancer patients vs. healthy controls): 342 [260;480] vs. 262 [189;388] vs. 190 [141;269] µg/l (p < .0001). In parallel with this, concentrations of IGF-II carried by IGFBP-2 averaged: 45.0 [33.3;52.5] vs. 34.2 [25.4;46.1] vs. 19.8 [14.1;26.0] µg/l (p < .0001), and concentrations of IGF-I 8.0 [5.2;11.8] vs. 5.4 [3.6;7.3] vs. 7.0 [3.8;13.0] µg/l (p < .0001). Thus, IGFBP-2 carried more IGF-II than IGF-I in all groups (p < .0001). When expressed relative to IGF-concentrations, IGFBP-2 carried 9.0 [5.3;15.5] % of the IGF-I and 4.8 [2.9;5.8] % of the IGF-II in serum from healthy subjects. Notably, in patients, IGFBP-2 carried relatively less IGF-I, but more IGF-II (p < .0001). CONCLUSION: Using our novel assay, we demonstrate: that IGFBP-2 carries ≈10% of circulating IGF-I and ≈5% of circulating IGF-II in healthy subjects; that IGF-II is the primary ligand for IGFBP-2; and that IGFBP-2 carries even more IGF-II in patients than in healthy subjects. Thus, our assay may provide information on IGFBP-2 beyond what is achievable by simply measuring ir-IGFBP-2.

Preoperative plasma IGFBP2 is associated with nodal metastasis in patients with penile squamous cell carcinoma.

PURPOSE: The nodal status is a strong predictor for clinical outcome in patients with penile cancer. We aimed to evaluate the association between preoperative plasma IGFBP2 levels and nodal status in patients with penile squamous cell carcinoma (PSCC). METHODS: This retrospective study enrolled 56 penile cancer patients who underwent penectomy between 2015 and 2017. Preoperative plasma IGFBP2 levels were detected by enzyme linked immunosorbent assay, which was analyzed in association with clinicopathological parameters (age, body mass index, pathological grade, phimosis, histological subtype, tumor stage, and nodal status). Univariable and Multivariable Cox regression analysis was conducted to identify the prognostic factors that influence disease free survival in PSCC. CCK8 assay and clonogenic assay were used to evaluate the cell viability and tumorigenic potential of PSCC cell line, respectively; wound healing assay, and transwell invasion assay were conducted to evaluate the effect of IGFBP2 depletion on cell migration and invasion in PSCC cells; IGFBP2 protein expression was analyzed by Western blotting. RESULTS: Plasma IGFBP2 levels were markedly higher in preoperative PSCC than those in healthy male subjects (P = 0.0007). Penectomy led to a significant reduction of plasma IGFBP2 levels in PSCC patients (P = 0.0098). Preoperative plasma IGFBP2 levels were significantly associated with nodal status of PSCC (P < 0.0001). At the cutoff value of 486.2 ng/ml, preoperative plasma IGFBP2 produced a sensitivity of 80.8% and a specificity of 86.7% to discriminate nodal metastasis. Preoperative plasma IGFBP2 levels could serve as independent prognostic factor for disease free survival in PSCC (P = 0.001). Further, knockdown of IGFBP2 expression suppressed cell growth, inhibited clonogenesis, and attenuated cell migration and invasion in Penl1 cells; depletion of IGFBP2 expression attenuated the levels of p-AKT and p-ERK1/2, while increased the expression of p16 and cleaved caspase-3 in Penl1 cells. Silencing IGFBP2 also led to a considerable decline of MMP2/9 levels in culture supernatant of Penl1 cells. CONCLUSION: Higher preoperative plasma IGFBP2 was closely associated with nodal metastasis, which might serve as a useful diagnostic and prognostic biomarker for clinical management of PSCC. IGFBP2 might play an important role in the malignant progression of PSCC. Therapeutic strategies targeting IGFBP2-related signaling pathways may have a therapeutic benefit in PSCC patients.

Serum IGF-binding protein 2 (IGFBP-2) concentrations change early after gastric bypass bariatric surgery revealing a possible marker of leptin sensitivity in obese subjects.

PURPOSE: Expression of IGFBP-2 in mice is regulated by leptin. Over-expression of IGFBP-2 is associated with reduced caloric intake and resistance to weight gain. Hormonal variations contributing to weight loss occur very early after bariatric surgery but have not been fully elucidated. We evaluated IGFBP-2 serum changes after bariatric surgery and their relationship with leptin variations to test the hypothesis that an increase of leptin sensitivity may explain some of the effects of gastric bypass. METHODS: This is a historical prospective study. Fifty-one obese patients (41 women e 10 men), 9 non-obese surgical controls and 41 lean matched controls were studied. Serum IGFBP-2 and leptin were measured after bariatric bypass surgery at various time points up to 18 months, after non-bariatric laparoscopic surgery in a control group, and in lean matched controls. RESULTS: Compared to lean controls, serum IGFBP-2 levels were lower in obese patients. After gastric bypass, IGFBP-2 significantly increased at 3 days and became normal before the occurrence of relevant changes in body weight, remaining stable up to 18 months after surgery. IGFBP-2/leptin ratio increased early after surgery and became normal after one year. CONCLUSIONS: After gastric bypass, serum IGFBP-2 increases in a window of time when variations of hormones mediating the effects of bariatric surgery occur. Our results suggest that IGFBP-2, a leptin-regulated protein, may be an in-vivo marker of leptin action. If this is the case, an early improvement of leptin sensitivity might contribute to the anorectic effect of gastric bypass.

The insulin-like growth factor family and breast cancer prognosis: A prospective cohort study among postmenopausal women in Denmark.

OBJECTIVE: Circulating levels of insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) have been associated with breast cancer (BC) risk. The evidence in relation to BC prognosis is limited. We aimed to evaluate the association between pre-diagnostic serum levels of IGF-I, IGF-II, IGFBP-2, IGFBP-3 and BC prognosis (i.e. recurrence, BC specific mortality and all-cause mortality) among women diagnosed with BC. We hypothesized that higher serum levels of IGFs and IGFBPs were associated with poor BC prognosis and that the associations were modified by estrogen receptor (ER) status. DESIGN: From the Danish Diet, Cancer and Health cohort, 412 postmenopausal women diagnosed with incident BC within 5 years of cohort baseline (1993-1997) were identified. Baseline serum samples were analyzed for IGF-I, IGF-II, IGFBP-2 and IGFBP-3. Follow-up was carried out through 2014 by linkage to national Danish registries. Exposures were related to BC prognosis by Cox Proportional Hazard models; effect modification by ER status was investigated and sensitivity analyses by follow-up time were made. RESULTS: During a median of 15 years, 106 women experienced recurrence and 172 died (118 due to BC). Overall, no associations were observed between IGF-I, IGF-II, IGFBP-2, IGFBP-3 and BC prognosis and no effect modification by ER status was observed. However, higher levels of IGF-II were associated with higher BC specific mortality [Hazard Ratio (HR) (95% Confidence Intervals (CI)): 1.43 (1.01-2.04)] within 10 years of follow-up. Likewise, higher levels of IGFBP-2 were associated with higher BC specific mortality [HR (95% CI): 1.87 (1.19-2.94)] within 5 years of follow-up. In contrast, higher levels of IGFBP-3 were associated with lower risk of recurrence [HR (95% CI): 0.76 (0.60-0.97)] at 5 years of follow-up and BC specific mortality [HR (95% CI): 0.80 (0.65-0.98)] within 10 years of follow-up. CONCLUSIONS: The present study did not support an association between higher serum levels of IGFs, IGFBPs and adverse BC prognosis. However, it is possible that the role of the IGF family in the etiology of the 5-10 year BC prognosis is different from that of longer-term BC prognosis.

IGFBP-2 and aging: a 20-year longitudinal study on IGFBP-2, IGF-I, BMI, insulin sensitivity and mortality in an aging population.

Objective Insulin-like growth factor-binding protein-2 (IGFBP-2) concentrations are low in subjects with metabolic syndrome and type 2 diabetes. Intriguingly, recent studies have demonstrated an association between high IGFBP-2 concentrations and increased mortality not only in populations with certain types of cancer, but also in relatively healthy populations. We evaluated the role of IGFBP-2 in relation to BMI and mortality. Design and Participants BMI, insulin sensitivity, insulin-like growth factor 1 (IGF-I) and IGFBP-2 were assessed repeatedly in 539 participants of the Baltimore Longitudinal Study of Aging around the ages of 55, 65 and 75 years. Results IGFBP-2 concentrations positively correlated with insulin sensitivity and inversely with BMI, both at baseline and follow-up. Independent of IGF-I, sex, BMI and insulin sensitivity, circulating IGFBP-2 levels positively correlated with age (P < 0.001). Changes over time in BMI were associated with an inverse correlation in IGFBP-2 concentrations. Furthermore, we found indications of a relationship between low baseline IGFBP-2 levels and mortality. Remarkably, after adjustment for insulin sensitivity, the opposite association was found, as a unit increase of log(IGFBP2) was associated with an increase in the log hazard by 1.43 (95% CI: 0.3-2.6). This accounted for both baseline (P = 0.02) as well as serial (P < 0.001) measurements of IGFBP2. Finally, in this longitudinal study, we found that IGF-I concentrations increased with age (0.82 ± 0.2 (µg/L)/year, P < 0.001). Conclusion This is the first study investigating the relationship between IGFBP-2 levels and age in a longitudinal setting. Serum IGFBP-2 levels increase with age after the age of 50 years and evolve in parallel with insulin sensitivity. IGFBP-2 may therefore be a potential marker for insulin sensitivity. We further show that IGFBP-2 levels can predict mortality in this aging population. However, its predictive value for mortality can only be interpreted in relation to insulin sensitivity. After adjustment for insulin sensitivity, high IGFBP-2 levels are predictive of increased mortality.

Proteins Altered by Surgical Weight Loss Highlight Biomarkers of Insulin Resistance in the Community.

Objective- Mechanisms of early and late improvements in cardiovascular risk after bariatric surgery and applicability to larger, at-risk populations remain unclear. We aimed to identify proteins altered after bariatric surgery and their relations to metabolic syndrome and diabetes mellitus. Approach and Results- We identified 19 proteins altered in 32 nonfasting plasma samples from a study of patients undergoing bariatric surgery who were evaluated preoperatively (visit 1) versus both early (visit 2; ≈3 months) and late (visit 3; ≈12 months) postoperative follow-up using predefined protein panels (Olink). Using in silico methods and publicly available gene expression repositories, we found that genes encoding 8 out of 19 proteins had highest expression in liver relative to other assayed tissues, with the top biological and disease processes, including major obesity-related vascular diseases. Of 19 candidate proteins in the surgical cohort, 6 were previously measured in >3000 FHS (Framingham Heart Study) participants (IGFBP [insulin-like growth factor binding protein]-1, IGFBP-2, P-selectin, CD163, LDL (low-density lipoprotein)-receptor, and PAI [plasminogen activator inhibitor]-1). A higher concentration of IGFBP-2 at baseline was associated with a lower risk of incident metabolic syndrome (odds ratio per log-normal unit, 0.45; 95% CI, 0.32-0.64; P=7.7×10-6) and diabetes mellitus (odds ratio, 0.63; 95% CI, 0.49-0.79; P=0.0001) after multivariable adjustment. Conclusions- Using a directed protein quantification platform (Olink), we identified known and novel proteins altered after surgical weight loss, including IGFBP-2. Future efforts in well-defined obesity intervention settings may further define and validate novel targets for the prevention of vascular disease in obesity.

Osteosarcoma enters a post genomic era with in silico opportunities: Generation of the High Dimensional Database for facilitating sarcoma biology research: A report from the Children's Oncology Group and the QuadW Foundation.

The prospective banking of osteosarcoma tissue samples to promote research endeavors has been realized through the establishment of a nationally centralized biospecimen repository, the Children's Oncology Group (COG) biospecimen bank located at the Biopathology Center (BPC)/Nationwide Children's Hospital in Columbus, Ohio. Although the physical inventory of osteosarcoma biospecimens is substantive (>15,000 sample specimens), the nature of these resources remains exhaustible. Despite judicious allocation of these high-value biospecimens for conducting sarcoma-related research, a deeper understanding of osteosarcoma biology, in particular metastases, remains unrealized. In addition the identification and development of novel diagnostics and effective therapeutics remain elusive. The QuadW-COG Childhood Sarcoma Biostatistics and Annotation Office (CSBAO) has developed the High Dimensional Data (HDD) platform to complement the existing physical inventory and to promote in silico hypothesis testing in sarcoma biology. The HDD is a relational biologic database derived from matched osteosarcoma biospecimens in which diverse experimental readouts have been generated and digitally deposited. As proof-of-concept, we demonstrate that the HDD platform can be utilized to address previously unrealized biologic questions though the systematic juxtaposition of diverse datasets derived from shared biospecimens. The continued population of the HDD platform with high-value, high-throughput and mineable datasets allows a shared and reusable resource for researchers, both experimentalists and bioinformatics investigators, to propose and answer questions in silico that advance our understanding of osteosarcoma biology.

A combined biomarker panel shows improved sensitivity for the early detection of ovarian cancer allowing the identification of the most aggressive type II tumours.

BACKGROUND: There is an urgent need for biomarkers for the early detection of ovarian cancer (OC). The purpose of this study was to assess whether changes in serum levels of lecithin-cholesterol acyltransferase (LCAT), sex hormone-binding globulin (SHBG), glucose-regulated protein, 78 kDa (GRP78), calprotectin and insulin-like growth factor-binding protein 2 (IGFBP2) are observed before clinical presentation and to assess the performance of these markers alone and in combination with CA125 for early detection. METHODS: This nested case-control study used samples from the United Kingdom Collaborative Trial of Ovarian Cancer Screening trial. The sample set consisted of 482 serum samples from 49 OC subjects and 31 controls, with serial samples spanning up to 7 years pre-diagnosis. The set was divided into the following: (I) a discovery set, which included all women with only two samples from each woman, the first at<14 months and the second at >32 months to diagnosis; and (ii) a corroboration set, which included all the serial samples from the same women spanning the 7-year period. Lecithin-cholesterol acyltransferase, SHBG, GRP78, calprotectin and IGFBP2 were measured using ELISA. The performance of the markers to detect cancers pre-diagnosis was assessed. RESULTS: A combined threshold model IGFBP2 >78.5 ng ml-1 : LCAT <8.831 µg ml-1 : CA125 >35 U ml-1 outperformed CA125 alone for the earlier detection of OC. The threshold model was able to identify the most aggressive Type II cancers. In addition, it increased the lead time by 5-6 months and identified 26% of Type I subjects and 13% of Type II subjects that were not identified by CA125 alone. CONCLUSIONS: Combined biomarker panels (IGFBP2, LCAT and CA125) outperformed CA125 up to 3 years pre-diagnosis, identifying cancers missed by CA125, providing increased diagnostic lead times for Type I and Type II OC. The model identified more aggressive Type II cancers, with women crossing the threshold dying earlier, indicating that these markers can improve on the sensitivity of CA125 alone for the early detection of OC.

Interactions of the Insulin-Like Growth Factor Axis and Vitamin D in Prostate Cancer Risk in the Prostate Cancer Prevention Trial.

Some, but not all, epidemiologic studies report an association between vitamin D and prostate cancer risk. The inconsistent findings might be explained in the context of modification by members of the insulin-like growth factor (IGF) axis. Data and specimens for this nested case-control study (n = 1695 cases and n = 1682 controls) are from the Prostate Cancer Prevention Trial (PCPT). Baseline serum samples were assayed for 25(OH)D, IGF-1, IGF-2, IGFBP-2, IGFBP-3, and the ratio of IGF1:BP3, along with insulin-related markers c-peptide and leptin. The presence of prostate cancer was assessed by prostate biopsy. Multivariate logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CIs) for prostate cancer risk. There were no interactions between serum 25(OH)D and IGF analytes in relation to prostate cancer risk when PCPT treatment arms were combined. In the placebo arm, above median serum 25(OH)D levels were associated with increased risk of prostate cancer among men with higher IGF-2 (OR:1.33, 95% CI: 1.00-1.65), with a significant interaction between 25(OH)D and treatment arm (Pinteraction = 0.04). Additionally, there was an interaction between treatment arm and serum IGFBP-3 (Pinteraction = 0.03). Higher serum 25(OH)D may increase risk of prostate cancer in the presence of higher circulating IGF-2.

Preoperative serum levels of insulin-like growth factor-binding protein 2 predict prognosis of gastric cancer patients.

It has been reported that serum insulin-like growth factor-binding protein 2 (IGFBP2) levels are elevated in various types of cancers. However, the clinicopathologic and prognostic implications of circulating IGFBP2 have never been investigated in gastric cancer. We tested IGFBP2 levels in the sera of 118 gastric cancer patients and 34 healthy controls using enzyme-linked immunosorbent assay (ELISA). The mean serum IGFBP2 level was significantly elevated in the gastric cancer patients compared to controls (805.23 ± 590.56 ng/ml vs. 459.61 ± 277.01 ng/ml; P < 0.001). Serum IGFBP2 levels were significantly higher in larger (> 6 cm) tumors (956.8 ± 734.0 ng/ml vs. 548.6 ± 364.0 ng/ml; P = 0.007) and in higher (T3/4) T stages (854.8 ± 621.4 ng/ml vs. 546.5 ± 315.1 ng/ml; P = 0.037). Multivariate Cox analysis showed that higher serum IGFBP2 level (> 400.01 ng/ml) was an independent prognostic factor predicting worse overall survival in patients with gastric cancer (hazard ratio (HR): 3.749, P = 0.034). When we divided patients into four groups based on blood IGFBP2 levels, survival was stratified. The HRs for death in the 3rd and 4th quartiles of serum IGFBP2 levels in comparison to that in the 1st quartile were 2.527 (P = 0.043) and 3.092 (P = 0.012). In conclusion, circulating IGFBP2 has potential as a biomarker predicting prognosis for gastric cancer patients.

Identification of IGFBP2 and IGFBP3 As Compensatory Biomarkers for CA19-9 in Early-Stage Pancreatic Cancer Using a Combination of Antibody-Based and LC-MS/MS-Based Proteomics.

Pancreatic cancer is one of the most lethal tumors, and reliable detection of early-stage pancreatic cancer and risk diseases for pancreatic cancer is essential to improve the prognosis. As 260 genes were previously reported to be upregulated in invasive ductal adenocarcinoma of pancreas (IDACP) cells, quantification of the corresponding proteins in plasma might be useful for IDACP diagnosis. Therefore, the purpose of the present study was to identify plasma biomarkers for early detection of IDACP by using two proteomics strategies: antibody-based proteomics and liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomics. Among the 260 genes, we focused on 130 encoded proteins with known function for which antibodies were available. Twenty-three proteins showed values of the area under the curve (AUC) of more than 0.8 in receiver operating characteristic (ROC) analysis of reverse-phase protein array (RPPA) data of IDACP patients compared with healthy controls, and these proteins were selected as biomarker candidates. We then used our high-throughput selected reaction monitoring or multiple reaction monitoring (SRM/MRM) methodology, together with an automated sample preparation system, micro LC and auto analysis system, to quantify these candidate proteins in plasma from healthy controls and IDACP patients on a large scale. The results revealed that insulin-like growth factor-binding protein (IGFBP)2 and IGFBP3 have the ability to discriminate IDACP patients at an early stage from healthy controls, and IGFBP2 appeared to be increased in risk diseases of pancreatic malignancy, such as intraductal papillary mucinous neoplasms (IPMNs). Furthermore, diagnosis of IDACP using the combination of carbohydrate antigen 19-9 (CA19-9), IGFBP2 and IGFBP3 is significantly more effective than CA19-9 alone. This suggests that IGFBP2 and IGFBP3 may serve as compensatory biomarkers for CA19-9. Early diagnosis with this marker combination may improve the prognosis of IDACP patients.

Insulin-Like Growth Factors (IGF) and IGF-Binding Proteins (IGFBP) in the Serum of Patients with Ovarian Tumors.

IGF-1, IGF-2, and IGFBP-1,2,3 were assayed in blood serum of patients with malignant ovarian tumors (n=44), borderline ovarian tumors (n=11), and benign ovarian tumors (n=12) as well as in healthy women (n=33). In blood serum of patients with malignant ovarian tumors, the level of IGF-1 was lower and IGFBP-1 was higher than in other groups. In patients with malignant and borderline ovarian tumors, the level of IGFBP-2 was higher than in healthy women and in patients with benign ovarian tumors. There was no correlation between most examined parameters and the clinical and morphological peculiarities of ovarian tumors. The study revealed IGF/IGFBP imbalance in patients with malignant ovarian tumor and showed that IGFBP-2 proved to be a potential diagnostic serological marker w with 90% sensitivity and 90% specificity.

Raised serum levels of IGFBP-1 and IGFBP-2 in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic lung disorder of unknown origin, which ultimately leads to death. Several growth factors such as IGFs (insulin-like-growth factor) and IGFBPs (insulin like growth factor binding proteins) seem to take part to the pathogenesis. We evaluated IGFs and IGFBPs in serum from patients with IPF and healthy subjects including 24 untreated IPF and 26 IPF receiving anti-fibrotic therapy and to compare them with healthy subjects. METHODS: Serum of 50 idiopathic pulmonary fibrosis and 55 healthy subjects (HS) were analysed by ELISA for IGFs and IGFBPs, TGF-ß and KL-6, the latter being tested as positive control in IPF. RESULTS: Serum levels of IGFBP-1 and IGFBP-2 and KL-6 were significantly higher in the IPF group than in the healthy subjects (p < 0.05, p < 0.001 and p < 0.0001 respectively) while the picture was inversed regarding IGFs. By contrast there was no significant difference between the groups with respect to TGF-ß. IGFBP-2 was significantly reduced in the patients with specific anti-fibrotic therapy pirfenidone and nintedanib compared to untreated patients (p < 0.05) but still significantly elevated in comparison to HS (p < 0.001). CONCLUSION: Serum IGFBP-1 and -2 are increased in idiopathic pulmonary fibrosis and IGFBP-2 may be reduced by anti-fibrosing therapy. IGFBPs may be promising biomarkers in IPF.