Insulin-like growth factor binding protein-2 is a novel therapeutic target associated with breast cancer.

PURPOSE: Insulin-like growth factor (IGF) binding proteins (IGFBP) modulate interactions of IGF ligands with the IGF-I receptor. The role of IGFBPs, and specifically IGFBP-2, in breast cancer progression has been poorly defined. This study assesses the effect of IGFBP-2 on the behavior of human breast cancer using clinical specimens as well as in vitro and in vivo experimental systems. EXPERIMENTAL DESIGN: 4,181 primary invasive breast cancers and 120 benign breast tissue samples were identified for tumor tissue microarray construction and immunostained with IGFBP-2 antibody. Estrogen receptor-negative MDA-MB-231 cells constitutively overexpressing IGFBP-2 (MDA-MB-231BP-2) were created to assess the effect of IGFBP-2 gain-of-function. MDA-MB-468 cells, naturally expressing IGFBP-2, were used to determine the effect of IGFBP-2 loss-of-function using OGX-225, an antisense oligonucleotide drug candidate. RESULTS: IGFBP-2 expression was significantly higher in breast cancer tissue compared with benign breast tissue. MDA-MB-231BP-2 cells grew more rapidly and were more resistant to paclitaxel both in vitro and in vivo compared with parental cells. OGX-225 decreased IGFBP-2 expression and attenuated the associated aggressive phenotype of MDA-MB-231BP-2 cells both in vitro and in vivo. Furthermore, OGX-225 inhibited the in vitro and in vivo growth of MDA-MB-468 cells. CONCLUSIONS: This study provides evidence that IGFBP-2 expression is associated with breast cancer. Novel therapeutics targeting IGFBP-2, such as OGX-225, merit further evaluation.

Evidence and Value: Impact on DEcisionMaking--the EVIDEM framework and potential applications.

BACKGROUND: Healthcare decisionmaking is a complex process relying on disparate types of evidence and value judgments. Our objectives for this study were to develop a practical framework to facilitate decisionmaking in terms of supporting the deliberative process, providing access to evidence, and enhancing the communication of decisions. METHODS: Extensive analyses of the literature and of documented decisionmaking processes around the globe were performed to explore what steps are currently used to make decisions with respect to context (from evidence generation to communication of decision) and thought process (conceptual components of decisions). Needs and methodologies available to support decisionmaking were identified to lay the groundwork for the EVIDEM framework. RESULTS: A framework was developed consisting of seven modules that can evolve over the life cycle of a healthcare intervention. Components of decision that could be quantified, i.e., intrinsic value of a healthcare intervention and quality of evidence available, were organized into matrices. A multicriteria decision analysis (MCDA) Value Matrix (VM) was developed to include the 15 quantifiable components that are currently considered in decisionmaking. A methodology to synthesize the evidence needed for each component of the VM was developed including electronic access to full text source documents. A Quality Matrix was designed to quantify three criteria of quality for the 12 types of evidence usually required by decisionmakers. An integrated system was developed to optimize data analysis, synthesis and validation by experts, compatible with a collaborative structure. CONCLUSION: The EVIDEM framework promotes transparent and efficient healthcare decisionmaking through systematic assessment and dissemination of the evidence and values on which decisions are based. It provides a collaborative framework that could connect all stakeholders and serve the healthcare community at local, national and international levels by allowing sharing of data, resources and values. Validation and further development is needed to explore the full potential of this approach.

The hedgehog pathway inhibitor cyclopamine increases levels of p27, and decreases both expression of IGF-II and activation of Akt in PC-3 prostate cancer cells.

The hedgehog signalling inhibitor cyclopamine has been shown to induce growth inhibition and cell cycle arrest in prostate cancer cell lines, but the mechanism of action has not been clearly defined, and observations between laboratories have not always been consistent. We first observed that albumin can protect PC-3 prostate cancer cells from cyclopamine-induced growth inhibition, suggesting that cyclopamine binds to albumin, and that only free cyclopamine is active. We then conducted a phospho-site protein kinase screen to elucidate the mechanism of cyclopamine-induced growth inhibition. Treatment of PC-3 cells with 5 or 10 microM cyclopamine for 72h resulted in a decrease in cell viability of approximately 50% and approximately 75%, respectively. A phospho-site protein kinase screen showed that cyclopamine decreased levels of phospho-Thr(187)-p27 by 71%. This phospho-site on p27 positively regulates its ubiquitin degradation; therefore a decrease in phospho-Thr(187)-p27 should correlate with increased levels of p27. Consistent with this hypothesis, treatment of PC-3 cells with cyclopamine resulted in a approximately 3-fold increase in p27 protein levels. Cdk-2 phosphorylates Thr(187)-p27, and immunoblotting demonstrated that cyclopamine treatment of PC-3 cells reduces the expression of cdk-2. Furthermore, cyclopamine decreased the levels of phosphorylated (activated) Akt, which is known to increase p27 degradation via Skp-2-induced ubiquitination. The mechanism by which cyclopamine decreases phosphorylated Akt is currently under investigation, but it may involve our observed cyclopamine-induced reduction in IRS-1 and IGF-II expression. These results demonstrate novel molecular correlates of cyclopamine-induced growth inhibition of prostate cancer cells.

Insulin-like growth factor-I antagonizes the antiproliferative effects of cyclooxygenase-2 inhibitors on BxPC-3 pancreatic cancer cells.

Cyclooxygenase (COX)-2 inhibitors demonstrate modest antineoplastic activity in experimental models of human malignancies, but little is known about factors that may confer resistance to their antiproliferative actions. We observed that fetal bovine serum antagonizes growth inhibition and G(1) arrest induced by two COX-2 inhibitors (NS-398 and celecoxib) on BxPC-3 pancreatic cancer cells. We investigated the hypothesis that insulin-like growth factor I (IGF-I), a major survival factor present in serum, mediates these effects. Treatment of BxPC-3 cells with 25 micro M celecoxib in 1% fetal bovine serum-containing medium for 48 h resulted in a approximately 40% decrease in cell viability. Coincubation of BxPC-3 cells with 25 micro M celecoxib and 50 ng/ml IGF-I resulted in complete attenuation of the celecoxib-associated decrease in cell viability. Cell cycle analysis revealed that this IGF-I-induced increase in cell viability was correlated with an IGF-I-induced inhibition of celecoxib-mediated G(1) arrest. Similar results were observed when another COX-2 inhibitor (50 micro M NS-398) was used. When IGF-binding protein-3 (an inhibitor of IGF-I bioactivity) was added in combination with 25 micro M celecoxib, enhanced growth inhibition was observed (approximately 60% decrease in cell viability). Treatment of BxPC-3 cells with a higher dose (50 micro M) of celecoxib for 24 h resulted in the induction of apoptosis, as assayed by flow cytometry and poly(ADP-ribose) polymerase cleavage. Addition of 50 ng/ml IGF-I resulted in a complete attenuation of celecoxib-induced apoptosis. The protection from celecoxib-induced apoptosis by IGF-I correlated with an increase in the levels of the activated antiapoptotic protein Akt. These results suggest that alterations of IGF-I levels or IGF-I receptor signal transduction modulate the antineoplastic actions of COX-2 inhibitors.

Extended-release tramadol/paracetamol in moderate-to-severe pain: a randomized, placebo-controlled study in patients with acute low back pain.

OBJECTIVE: Combinations of oral analgesics may offer several potential benefits compared with an individual agent. The objective of this study was to investigate the efficacy and safety of an extended-release, twice-daily fixed combination of 75 mg tramadol/650 mg paracetamol (DDS-06C) in the treatment of moderate-to-severe pain, using acute low back pain as a model. RESEARCH DESIGN AND METHODS: In this phase III study, 277 patients with moderate-to-severe acute low back pain were randomized to 1-2 tablets of DDS-06C or placebo every 10-12 h for 2.5 days during the double-blind phase. Following the double-blind phase, patients had the option to continue for a 2.5-day open-label phase. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (Identifier: NCT00643383) MAIN OUTCOME MEASURES: The primary end point was the sum of pain intensity differences (SPID) over the 50-h double-blind phase (SPID50). Secondary end points included total pain relief score over the 50-h double-blind phase (TOTPAR50), patient's global impression of medication, and SPID over the first 4 h. RESULTS: A statistically significant (p = 0.038) greater decrease in pain intensity was observed in the DDS-06C group (median SPID50: -6.0) versus placebo (median SPID50: -4.0). Greater pain relief was also observed in patients randomized to DDS-06C: the median TOTPAR50 was 13.0 for the DDS-06C group and 11.0 for placebo (p = 0.026). DDS-06C demonstrated statistically significant superior efficacy compared with placebo for the majority of the other secondary end points. Overall, 38% of patients treated with DDS-06C experienced at least one adverse event; the intensity was mild-to-moderate in 81% of cases. The most commonly reported adverse events (>5% of patients receiving DDS-06C) were nausea, dizziness, vomiting, and somnolence. CONCLUSIONS: Using acute low back pain, a model with a high degree of heterogeneity and intrinsic variability, DDS-06C was superior to placebo on measures of pain intensity and relief, and was well-tolerated.

Bridging health technology assessment (HTA) and efficient health care decision making with multicriteria decision analysis (MCDA): applying the EVIDEM framework to medicines appraisal.

BACKGROUND: Health care decision making is complex and requires efficient and explicit processes to ensure transparency and consistency of factors considered. OBJECTIVES: To pilot an adaptable decision-making framework incorporating multicriteria decision analysis (MCDA) in health technology assessment (HTA) with a pan-Canadian group of policy and clinical decision makers and researchers appraising 10 medicines covering 6 therapeutic areas. METHODS: An appraisal group was convened and participants were asked to express their individual perspectives, independently of the medicines, by assigning weights to each criterion of the MCDA core model: disease severity, size of population, current practice and unmet needs, intervention outcomes (efficacy, safety, patient reported), type of health benefit, economics, and quality of evidence. Participants then assigned performance scores for each medicine using available evidence synthesized in a "by-criterion" HTA report covering each of the MCDA CORE model criteria. MCDA estimates of perceived value were calculated by combining normalized weights and scores. Feedback on the approach was collected through structured discussion. RESULTS: Relative weights on criteria varied widely, reflecting the diverse perspectives of participants. Scores for each criterion provided a performance measure, highlighting strengths and weaknesses of each medicine. MCDA estimates of perceived value ranged from 0.42 to 0.64 across medicines, providing comprehensive measures incorporating a large spectrum of criteria. Participants reported that the framework provided an efficient approach to systematic consideration in a pragmatic format of the multiple elements guiding decision, including criteria and values (MCDA core model) and evidence (HTA "by-criterion" report). CONCLUSIONS: This proof-of-concept study demonstrated the usefulness of incorporating MCDA in HTA to support transparent and systematic appraisal of health care interventions. Further research is needed to advance MCDA-based approaches to more effective healthcare decision making.

Extended-release Trazodone in Major Depressive Disorder: A Randomized, Double-blind, Placebo-controlled Study.

OBJECTIVE: To investigate the efficacy, safety, and clinical benefit of a once-daily formulation of trazodone (Trazodone Contramid((c)) OAD) in the treatment of major depressive disorder. DESIGN/PARTICIPANTS: In this double-blind study, 412 patients with major depressive disorder (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria) were randomized 1:1 to receive either Trazodone Contramid OAD (150 to 375mg) or placebo. Treatment was titrated over two weeks to each individual optimal dose. Patients then continued six weeks of treatment; further dose adjustments were allowed based on efficacy and tolerability. MEASUREMENTS: The primary end point was change in the 17-item Hamilton Depression Rating Scale total score from baseline to last study visit. Secondary end points included Hamilton Depression Rating Scale responders/remitters, change in Montgomery-Asberg Depression Rating Scale, Clinician and Patient Global Improvement Scales, and quality of sleep. RESULTS: From the end of titration to the end of the six-week treatment period, the mean maximum daily dose of the intent-to-treat population was 310mg for the active group and 355mg for the placebo group. There was a statistically significant difference between trazodone and placebo on the mean HAMD-17 score (-11.4 vs. -9.3, P=0.012). A significant difference was present as early as Week 1 and was maintained at all subsequent study visits. Many secondary end points supported these findings, including improvements in quality of sleep. The most frequent adverse events were the same for both the treatment and placebo groups: headache and somnolence. There were no serious adverse events that were considered related to treatment. There were no clinically significant electrocardiogram or laboratory abnormalities. CONCLUSIONS: The trazodone Contramid formulation was more effective than placebo in major depressive disorder and was well tolerated.

PTEN-induction in U251 glioma cells decreases the expression of insulin-like growth factor binding protein-2.

PTEN is a tumor suppressor gene whose loss of function is observed in approximately 40-50% of human cancers. Although insulin-like growth factor binding protein-2 (IGFBP-2) was classically described as a growth inhibitor, multiple recent reports have shown an association of overexpression and/or high serum levels of IGFBP-2 with poor prognosis of several malignancies, including gliomas. Using an inducible PTEN expression system in the PTEN-null glioma cell line U251, we demonstrate that PTEN-induction is associated with reduced proliferation, increased apoptosis, and a substantial reduction of the high levels of IGFBP-2 expression. The PTEN-induced decrease in IGFBP-2 expression could be mimicked with the PI3-kinase inhibitor LY294002, indicating that the lipid phosphatase activity of PTEN is responsible for the observed effect. However, the rapamycin analog CCI-779 did not affect IGFBP-2 expression, suggesting that the PTEN-induced decrease in IGFBP-2 expression is not attributable to decreased mTOR signalling. Recombinant human IGFBP-2 was unable to rescue U251-PTEN cells from the antiproliferative effects of PTEN, and IGFBP-2 siRNA did not affect the IGF-dependent or -independent growth of this cell line. These results suggest that the clinical data linking IGFBP-2 expression to poor prognosis may arise, at least in part, because high levels of IGFBP-2 expression correlate with loss of function of PTEN, which is well known to lead to aggressive behavior of gliomas. Our results motivate translational research regarding the relationship between IGFBP-2 expression and loss of function of PTEN.

Growth inhibition of breast epithelial cells by celecoxib is associated with upregulation of insulin-like growth factor binding protein-3 expression.

Several experimental and epidemiological studies have suggested a role for the use of cyclooxygenase (COX)-2 inhibitors in the prevention of breast cancer. The relative lack of toxicity associated with these compounds favors their use as chemopreventive agents, but the underlying mechanism of their chemopreventive effect remains unclear. We have observed that the COX-2 inhibitor celecoxib inhibits growth and induces apoptosis in the immortalized breast epithelial cell line 184htert. Microarray gene expression analysis of 184htert cells treated with 50 microM celecoxib for 6h revealed the modulation of several genes of interest, including a significant induction of expression of the mRNA encoding insulin-like growth factor binding protein-3 (IGFBP-3). IGFBP-3 is a potent pro-apoptotic protein and growth inhibitor of breast cancer cells, which acts mainly by inhibiting the access of the mitogens IGF-I and IGF-II to their cell surface receptor, but also via IGF-independent effects. Quantitative real-time RT PCR demonstrated that 50 microM celecoxib induced a approximately 3-fold increase in expression of IGFBP-3 mRNA after 6h. Furthermore, ligand blot analysis revealed that celecoxib treatment was associated with the upregulation of IGFBP-3 at the protein level. IGFBP-3 (500 ng/ml) treatment of 184htert cells inhibited IGF-I and serum-induced proliferation, but had no effect on cell growth under serum-free conditions, indicating that IGF-independent effects of IGFBP-3 are not observed in this system. Our results suggest that celecoxib may decrease IGF-I-associated breast cancer risk by a mechanism involving induction of expression of IGFBP-3 and subsequent reduced proliferation of at-risk breast epithelial cells.