High-throughput screening of glucocorticoid-induced enhancer activity reveals mechanisms of stress-related psychiatric disorders

Exposure to stressful life events increases the risk for psychiatric disorders. Mechanistic insight into the genetic factors moderating the impact of stress can increase our understanding of disease processes. Here, we test 3,662 single nucleotide polymorphisms (SNPs) from preselected expression quantitative trait loci in massively parallel reporter assays to identify genetic variants that modulate the activity of regulatory elements sensitive to glucocorticoids, important mediators of the stress response. Of the tested SNP sequences, 547 were located in glucocorticoid-responsive regulatory elements of which 233 showed allele-dependent activity. Transcripts regulated by these functional variants were enriched for those differentially expressed in psychiatric disorders in the postmortem brain. Phenome-wide Mendelian randomization analysis in 4,439 phenotypes revealed potentially causal associations specifically in neurobehavioral traits, including major depression and other psychiatric disorders. Finally, a functional gene score derived from these variants was significantly associated with differences in the physiological stress response, suggesting that these variants may alter disease risk by moderating the individual set point of the stress response.

Tripartite extended amygdala-basal ganglia CRH circuit drives locomotor activation and avoidance behavior

An adaptive stress response involves various mediators and circuits orchestrating a complex interplay of physiological, emotional, and behavioral adjustments. We identified a population of corticotropin-releasing hormone (CRH) neurons in the lateral part of the interstitial nucleus of the anterior commissure (IPACL), a subdivision of the extended amygdala, which exclusively innervate the substantia nigra (SN). Specific stimulation of this circuit elicits hyperactivation of the hypothalamic-pituitary-adrenal axis, locomotor activation, and avoidance behavior contingent on CRH receptor type 1 (CRHR1) located at axon terminals in the SN, which originate from external globus pallidus (GPe) neurons. The neuronal activity prompting the observed behavior is shaped by IPACL^CRH and GPe^CRHR1 neurons coalescing in the SN. These results delineate a previously unidentified tripartite CRH circuit functionally connecting extended amygdala and basal ganglia nuclei to drive locomotor activation and avoidance behavior.

Focus on Causality in ESC/iPSC-Based Modeling of Psychiatric Disorders

Genome-wide association studies (GWAS) have identified an increasing number of genetic variants that significantly associate with psychiatric disorders. Despite this wealth of information, our knowledge of which variants causally contribute to disease, how they interact, and even more so of the functions they regulate, is still poor. The availability of embryonic stem cells (ESCs) and the advent of patient-specific induced pluripotent stem cells (iPSCs) has opened new opportunities to investigate genetic risk variants in living disease-relevant cells. Here, we analyze how this progress has contributed to the analysis of causal relationships between genetic risk variants and neuronal phenotypes, especially in schizophrenia (SCZ) and bipolar disorder (BD). Studies on rare, highly penetrant risk variants have originally led the field, until more recently when the development of (epi-) genetic editing techniques spurred studies on cause-effect relationships between common low risk variants and their associated neuronal phenotypes. This reorientation not only offers new insights, but also raises issues on interpretability. Concluding, we consider potential caveats and upcoming developments in the field of ESC/iPSC-based modeling of causality in psychiatric disorders.

Childhood-Onset Schizophrenia: Insights from Induced Pluripotent Stem Cells

Childhood-onset schizophrenia (COS) is a rare psychiatric disorder characterized by earlier onset, more severe course, and poorer outcome relative to adult-onset schizophrenia (AOS). Even though, clinical, neuroimaging, and genetic studies support that COS is continuous to AOS. Early neurodevelopmental deviations in COS are thought to be significantly mediated through poorly understood genetic risk factors that may also predispose to long-term outcome. In this review, we discuss findings from induced pluripotent stem cells (iPSCs) that allow the generation of disease-relevant cell types from early brain development. Because iPSCs capture each donor's genotype, case/control studies can uncover molecular and cellular underpinnings of COS. Indeed, recent studies identified alterations in neural progenitor and neuronal cell function, comprising dendrites, synapses, electrical activity, glutamate signaling, and miRNA expression. Interestingly, transcriptional signatures of iPSC-derived cells from patients with COS showed concordance with postmortem brain samples from SCZ, indicating that changes in vitro may recapitulate changes from the diseased brain. Considering this progress, we discuss also current caveats from the field of iPSC-based disease modeling and how to proceed from basic studies to improved diagnosis and treatment of COS.

Tracing Early Neurodevelopment in Schizophrenia with Induced Pluripotent Stem Cells

Schizophrenia (SCZ) is a devastating mental disorder that is characterized by distortions in thinking, perception, emotion, language, sense of self, and behavior. Epidemiological evidence suggests that subtle perturbations in early neurodevelopment increase later susceptibility for disease, which typically manifests in adolescence to early adulthood. Early perturbations are thought to be significantly mediated through incompletely understood genetic risk factors. The advent of induced pluripotent stem cell (iPSC) technology allows for the in vitro analysis of disease-relevant neuronal cell types from the early stages of human brain development. Since iPSCs capture each donor's genotype, comparison between neuronal cells derived from healthy and diseased individuals can provide important insights into the molecular and cellular basis of SCZ. In this review, we discuss results from an increasing number of iPSC-based SCZ/control studies that highlight alterations in neuronal differentiation, maturation, and neurotransmission in addition to perturbed mitochondrial function and micro-RNA expression. In light of this remarkable progress, we consider also ongoing challenges from the field of iPSC-based disease modeling that call for further improvements on the generation and design of patient-specific iPSC studies to ultimately progress from basic studies on SCZ to tailored treatments.

Aligning Single-Cell Developmental and Reprogramming Trajectories Identifies Molecular Determinants of Myogenic Reprogramming Outcome

Cellular reprogramming through manipulation of defined factors holds great promise for large-scale production of cell types needed for use in therapy and for revealing principles of gene regulation. However, most reprogramming systems are inefficient, converting only a fraction of cells to the desired state. Here, we analyze MYOD-mediated reprogramming of human fibroblasts to myotubes, a well-characterized model system for direct conversion by defined factors, at pseudotemporal resolution using single-cell RNA-seq. To expose barriers to efficient conversion, we introduce a novel analytic technique, trajectory alignment, which enables quantitative comparison of gene expression kinetics across two biological processes. Reprogrammed cells navigate a trajectory with branch points that correspond to two alternative decision points, with cells that select incorrect branches terminating at aberrant or incomplete reprogramming outcomes. Analysis of these branch points revealed insulin and BMP signaling as crucial molecular determinants of reprogramming. Single-cell trajectory alignment enables rigorous quantitative comparisons between biological trajectories found in diverse processes in development, reprogramming, and other contexts.

Abstract 4728: Apoptotic priming is regulated by a developmental program and predisposes children to therapy-induced toxicity

Pediatric cancer patients frequently suffer higher levels of treatment-induced toxicities than adults, limiting the use of potentially curative therapies. For example, brain irradiation contributes to the cure of medulloblastomas in 80% of children yet also causes cell death in healthy neurons, resulting in a permanent and devastating loss of IQ. Likewise, children commonly experience dose-limiting cardiotoxicity from doxorubicin treatment. These treatments are comparatively well tolerated in adults yet the basis for this dramatic contrast in sensitivity is unknown. Both radiation and cytotoxic chemotherapies can induce an apoptotic cell death, prompting us to hypothesize that apoptosis may be regulated in a fundamentally different manner in children versus adults.

By testing the functional state of the apoptotic pathway in tissues with BH3 Profiling, we found that healthy brain, heart and kidney tissues from young mice are extremely sensitive to pro-apoptotic signals and are therefore “primed for apoptosis.” In stark contrast, these same tissues are completely insensitive to even saturating amounts of pro-apoptotic signals in adult mice. Apoptosis could be triggered in adult brain, heart or kidney cells only when complemented with exogenous BAX protein suggesting that these tissues lack sufficient levels of BAX or BAK for mitochondrial permeabilization and are thus “incompetent for apoptosis.” Immunoblotting revealed that BAX and BAK protein levels are strongly downregulated in these tissues during postnatal development and become nearly undetectable by adulthood, along with several other components of the apoptotic machinery. Parallel studies with spleen and bone marrow demonstrated high levels of apoptotic priming in young animals which continued into adulthood, highlighting the organ-specific nature of apoptosis regulation. In agreement with these findings, we observed apoptotic cell death in response to radiation damage in the brain, heart and kidneys of early postnatal but not adult mice. Likewise, the extent of doxorubicin-induced damage to cardiac tissue correlated strongly with changes in apoptotic priming and competence. Furthermore, we utilized BAX and/or BAK knockout mice to characterize the pivotal roles of these proteins in regulating apoptotic competence and damage responses in somatic tissues.

We extended these findings to humans by BH3 profiling normal brain tissue and confirmed that brain tissue in young children is primed to undergo apoptosis while in adults it is apoptotically incompetent. Finally, we identified the epigenetic mechanisms that modulate apoptotic pathways during postnatal development. Our findings elucidate the molecular mechanisms responsible for the devastating vital organ sensitivity to damage in children and a strategy for its prevention.

Citation Format: Kristopher A. Sarosiek, Michael Ziller, Cameron Fraser, Patrick Bhola, Jeremy Ryan, Jing Deng, Brian Jian, Marti Goldenberg, Joseph Madsen, Ruben Carrasco, Shenandoah Robinson, Javid Moslehi, Anthony Letai. Apoptotic priming is regulated by a developmental program and predisposes children to therapy-induced toxicity. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4728. doi:10.1158/1538-7445.AM2015-4728

Pathways disrupted in human ALS motor neurons identified through genetic correction of mutant SOD1

Although many distinct mutations in a variety of genes are known to cause Amyotrophic Lateral Sclerosis (ALS), it remains poorly understood how they selectively impact motor neuron biology and whether they converge on common pathways to cause neuronal degeneration. Here, we have combined reprogramming and stem cell differentiation approaches with genome engineering and RNA sequencing to define the transcriptional and functional changes that are induced in human motor neurons by mutant SOD1. Mutant SOD1 protein induced a transcriptional signature indicative of increased oxidative stress, reduced mitochondrial function, altered subcellular transport, and activation of the ER stress and unfolded protein response pathways. Functional studies demonstrated that these pathways were perturbed in a manner dependent on the SOD1 mutation. Finally, interrogation of stem-cell-derived motor neurons produced from ALS patients harboring a repeat expansion in C9orf72 indicates that at least a subset of these changes are more broadly conserved in ALS.

Effects of zoledronic acid on bone mineral density in premenopausal women receiving neoadjuvant or adjuvant therapies for HR+ breast cancer: the ProBONE II study

The effects of bisphosphonates on altered bone turnover marker (BTM) levels associated with adjuvant endocrine or chemotherapy in early breast cancer have not been systematically investigated. In ProBONE II, zoledronic acid decreased these elevated BTM levels and increased bone mineral density (BMD) during adjuvant therapy, consistent with its antiresorptive effects.

INTRODUCTION

Adjuvant chemotherapy or endocrine therapy for early hormone receptor-positive breast cancer (HR(+) BC) is associated with rapid BMD loss and altered BTM levels. Adjuvant bisphosphonate studies demonstrated BMD increases, but did not investigate BTM effects. The randomized, double-blind, ProBONE II study investigated the effect of adjuvant zoledronic acid (ZOL) on BMD and BTM in premenopausal women with early HR(+) BC.

METHODS

Seventy premenopausal women with early HR(+) BC received adjuvant chemotherapy and/or endocrine therapy plus ZOL (4 mg IV every 3 months) or placebo for 24 months. Primary endpoint was change in lumbar spine BMD at 24 months versus baseline. Secondary endpoints included femoral neck and total femoral BMD changes, changes in BTM, and safety.

RESULTS

Lumbar spine BMD increased 3.14% from baseline to 24 months in ZOL-treated participants versus a 6.43% decrease in placebo-treated participants (P < 0.0001). Mean changes in T- and Z-scores, and femoral neck and total femoral BMD, showed similar results. Bone resorption marker levels decreased ∼ 55% in ZOL-treated participants versus increases up to 65% in placebo-treated participants (P < 0.0001 for between-group differences). Bone formation marker (procollagen I N-terminal propeptide) levels decreased ∼ 57% in ZOL-treated participants versus increases up to 45% in placebo-treated participants (P < 0.0001 for between-group differences). Adverse events were consistent with the established ZOL safety profile and included one case of osteonecrosis of the jaw after a tooth extraction.

CONCLUSIONS

Adding ZOL to adjuvant therapy improved BMD, reduced BTM levels, and was well tolerated in premenopausal women with early HR(+) BC receiving adjuvant chemotherapy and/or endocrine therapy.

The prescribing of contraceptives for adolescents in German gynecologic practices in 2007 and 2011: a retrospective database analysis

OBJECTIVE

To investigate the prescribing trend of contraceptives in adolescent girls aged 12-18 years and to compare prescribing patterns of the most frequently used contraceptives among this population in Germany in 2007 and 2011.

METHODS

A retrospective cohort study was conducted to analyze contraceptive prescriptions written by gynecologists in 2007 and 2011 in Germany by using the IMS Disease Analyzer database (IMS HEALTH). All adolescent girls aged 12-18 years with at least 1 prescription of a contraceptive drug in 2007 or 2011 were identified. The prevalence of contraceptive prescriptions was calculated and the types of contraceptive substances prescribed were examined.

RESULTS

A total of 21,026 teenage girls in 2007 and 18,969 in 2011 received contraceptive prescriptions. The prevalence of contraceptive prescribing rose significantly between 2007 and 2011 (P < .001). The percentage of teen girls who received prescriptions of levonorgestrel and chlormadinone pills was significantly higher in 2011 compared to 2007 (P < .001). However, the portion of contraceptive pills containing drospirenone or desogestrel significantly decreased in 2011 compared to 2007 (P < .01).

CONCLUSION

There was a significant increase in contraceptive prescription usage among adolescent girls between 2007 and 2011 in Germany. However, the prescription behavior of doctors also changed; they consequently prescribed contraceptives with more evidence. Further research is needed to better understand the various factors associated with contraceptive use among this population.

Prevalence of female subfertility in German gynecological practices

INTRODUCTION

The aim of this study was to calculate the number of women with a subfertility diagnosis in gynecological practices in Germany between 2006 and 2010 based on the data from a large epidemiological database.

METHODS

All calculations are based on a representative, epidemiological database called "disease analyzer". Women with a confirmed diagnosis of female infertility (ICD 10: N97) or/and with documentation of procreative management (ICD 10: Z31) were identified. They were summarized under the term "subfertility".

RESULTS

In total, data on 1,975,253 female patients with between 2006 and 2010 were included. Estimates for patients with "subfertility" compared to number of women lived in Germany (aged 18-45) was 2.44% (CI: 2.43-2.45) in 2006, 2.52% (CI: 2.51-2.53) in 2007, 2.56% (CI: 2.55-2.57) in 2008, 2.68% (CI: 2.67-2.69) in 2009 and 2.69% (CI: 2.68-2.70) in 2010. The difference was significant (p < 0.01). In total, between 2006 and 2010 an estimated 8.91% of all German women had been diagnosed "subfertile".

CONCLUSION

When calculated for 5 years almost 1 out of 10 women aged 18 to 45 was counseled, investigated or treated by her gynecologist for "subfertility". This study provides reliable, representative data on a major healthcare issue in Germany.

Gel-free multiplexed reduced representation bisulfite sequencing for large-scale DNA methylation profiling

Sequencing-based approaches have led to new insights about DNA methylation. While many different techniques for genome-scale mapping of DNA methylation have been employed, throughput has been a key limitation for most. To further facilitate the mapping of DNA methylation, we describe a protocol for gel-free multiplexed reduced representation bisulfite sequencing (mRRBS) that reduces the workload dramatically and enables processing of 96 or more samples per week. mRRBS achieves similar CpG coverage to the original RRBS protocol, while the higher throughput and lower cost make it better suited for large-scale DNA methylation mapping studies, including cohorts of cancer samples.

P2-17-02: Increased Progression Free and Overall Survival in Breast Cancer Patients with Menopausal Symptoms or Arthralgia/Myalgia during Adjuvant Treatment with Exemestane or Tamoxifen – Results of the German TEAM Trial

Background

Previous studies have suggested a correlation between the occurrence of vasomotor or joint symptoms during tamoxifen or aromatase inhibitor treatment and improved clinical response. We assessed if there was any correlation between treatment-emergent adverse events during exemestane or tamoxifen treatment and clinical response.

Methods: A retrospective analysis of the German cohort of the TEAM trial was performed to assess progression-free survival and overall survival in patients with and without menopausal symptoms or arthralgia/myalgia during adjuvant treatment with exemestane or tamoxifen.

Results: A total of 1502 patients were included in this analysis; 739 patients received tamoxifen and 763 received exemestane. Patients reporting menopausal symptoms and patients reporting arthralgia/myalgia during tamoxifen or exemestane treatment had significantly longer overall survival and progression-free survival. The effect on overall survival was irrespective of treatment. Progression-free survival was significantly improved in exemestane-treated patients reporting menopausal symptoms or those reporting arthralgia/myalgia versus those not reporting these adverse events. There was no significant difference in progression-free survival between tamoxifen-treated patients reporting these symptoms versus those who did not. A combined analysis of patients reporting either menopausal symptoms or arthralgia/myalgia showed that overall survival and progressionfree survival was significantly improved in patients reporting one of these symptoms versus those not reporting either symptom. In this analysis, the effect on overall survival and progression-free survival was irrespective of treatment.

Conclusions: Our results suggest that the occurrence of menopausal symptoms or arthralgia/myalgia during treatment with tamoxifen or exemestane is associated with significantly improved overall survival.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-17-02.

P2-19-03: Influence of Zoledronic Acid on BMD in Premenopausal Women with Breast Cancer and Neoadjuvant or Adjuvant Chemotherapy and/or Endocrine Treatment – The ProBone Studies

Background: Based on baseline bone mineral density (BMD), adjuvant chemotherapy or endocrine therapy for early breast cancer patients can lead to substantially increased fracture risk. A significant decrease of BMD &gt;10% after 2 years of chemotherapy (CT) and/or endocrine therapy (ET) has been reported. In recent studies, zoledronic acid (ZOL) produced an increase in BMD in premenopausal and postmenopausal patients with breast cancer (ABCSG-12, Z-FAST, ZO-FAST, etc). In addition, a significant increase in disease-free survival (DFS) with ZOL vs no ZOL was observed in most of these studies.

Methods: The aim of 2 single-center, placebo-controlled, randomized studies—Probone I and Probone II—was to investigate the effect of adjuvant treatment with ZOL on BMD in premenopausal women with early breast cancer treated with CT and/or ET. Patients with hormone-receptor-negative (HR−) breast cancer (Probone I) were treated with (neo)adjuvant CT; patients with hormone-receptor-positive (HR+) breast cancer (Probone II) were treated with ET alone or in combination with (neo)adjuvant CT. Randomized patients received ZOL 4 mg or placebo IV every 3 months for 24 months. The primary objective was the change in BMD at the lumbar spine between baseline and month 24 (measured by dual-energy X-ray absorptiometry [DXA]). Secondary objectives included DFS; BMD at total hip, femur, and os calcis; quantitative ultrasonometry (QUS) at os calcis and phalanges; markers of bone turnover (C-telopeptide of type I collagen [CTX] and N-terminal propeptide of type I procollagen [P1NP]); endocrine hormones (follicle-stimulating hormone [FSH], estradiol, testosterone, sex hormone-binding globulin [SHBG], parathyroid hormone [PTH], vitamin D, anti-Müllerian hormone [AMH], inhibin A/B, etc); pathologic fractures; and safety and tolerability.

Results: 70 HR+ and 11 HR− breast cancer patients have been enrolled into the studies. The last patient will have been treated for 24 months by the end of June 2011.

Conclusions: The effects of ZOL on lumbar spine BMD at 24 months and secondary endpoints will be presented at the meeting.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-19-03.

Reference Maps of human ES and iPS cell variation enable high-throughput characterization of pluripotent cell lines

The developmental potential of human pluripotent stem cells suggests that they can produce disease-relevant cell types for biomedical research. However, substantial variation has been reported among pluripotent cell lines, which could affect their utility and clinical safety. Such cell-line-specific differences must be better understood before one can confidently use embryonic stem (ES) or induced pluripotent stem (iPS) cells in translational research. Toward this goal we have established genome-wide reference maps of DNA methylation and gene expression for 20 previously derived human ES lines and 12 human iPS cell lines, and we have measured the in vitro differentiation propensity of these cell lines. This resource enabled us to assess the epigenetic and transcriptional similarity of ES and iPS cells and to predict the differentiation efficiency of individual cell lines. The combination of assays yields a scorecard for quick and comprehensive characterization of pluripotent cell lines.

Broad spectrum reactivity versus subtype specificity-trade-offs in serodiagnosis of influenza A virus infections by competitive ELISA

Avian influenza viruses (AIVs) of the H5 and H7 subtypes can cause substantial economic losses in the poultry industry and are a potential threat to public health. Serosurveillance of poultry populations is an important monitoring tool and can also be used for control of vaccination campaigns. The purpose of this study was to develop broadly reactive, yet subtype-specific competitive ELISAs (cELISAs) for the specific detection of antibodies to the notifiable AIV subtypes H5 and H7 as an alternative to the gold standard haemagglutination inhibition assay (HI). Broadly reacting monoclonal competitor antibodies (mAbs) and genetically engineered subtype H5 or H7 haemagglutinin antigen, expressed and in vivo biotinylated in insect cells, were used to develop the cELISAs. Sera from galliform species and water fowl (n=793) were used to evaluate the performance characteristics of the cELISAs. For the H5 specific cELISA, 98.1% test sensitivity and 91.5% test specificity (97.7% and 90.2% for galliforms; 98.9% and 92.6% for waterfowl), and for the H7 cELISA 97.3% sensitivity and 91.8% specificity (95.3% and 98.9% for galliforms; 100% and 82.7% for waterfowl) were reached when compared to HI. The use of competitor mAbs with broad spectrum reactivity within an AIV haemagglutinin subtype allowed for homogenous detection with high sensitivity of subtype-specific antibodies induced by antigenically widely distinct isolates including antigenic drift variants. However, a trade-off regarding sensitivity versus nonspecific detection of interfering antibodies induced by phylo- and antigenically closely related subtypes, e.g., H5 versus H2 and H7 versus H15, must be considered. The observed intersubtype antibody cross-reactivity remains a disturbance variable in AIV subtype-specific serodiagnosis which negatively affects specificity.

Abstract P5-11-08: Effects of Exemestane or Tamoxifen on Bone Health within the Tamoxifen Exemestane Adjuvant Multinational (TEAM) Trial: A Meta-Analysis

Background: TEAM is the largest AI phase III trial comparing exemestane with tamoxifen followed by exemestane as adjuvant breast cancer therapy in postmenopausal women. We performed a meta-analysis of three randomized sub-studies of the TEAM trial conducted in Germany, the Netherlands/Belgium and the United States to determine the effects on bone health.

Methods: Patients were randomised to exemestane or tamoxifen as adjuvant therapy for hormone receptor-positive breast cancer. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry at baseline and after 6, 12 and 24 months’ treatment. Bone turnover markers were also measured.

Results: 412 patients were evaluable. Patients in the tamoxifen group showed a mean increase in lumbar spine BMD of 1.2% from baseline to month 12 and 0.2% to month 24. Patients in the exemestane group showed a mean decrease from baseline of 2.6% after 12 months and 3.5% after 24 months. There were significant differences in the changes in BMD at the lumbar spine between treatment groups (P&lt;0.0001 at both timepoints). In the tamoxifen group, a mean increase in total hip BMD of 0.8% from baseline to month 12 and a mean decrease from baseline of 0.4% after 24 months was observed, compared with a mean decrease of 1.3% after 12 months and 3.3% after 24 months in the exemestane group. Changes in BMD from baseline at the total hip were also significantly different between exemestane and tamoxifen (P&lt;0.05 at both timepoints). Bone turnover markers decreased from baseline with tamoxifen and increased with exemestane.

Conclusions: After 24 months, exemestane treatment resulted in decreases in BMD and increases in bone turnover markers. In contrast, BMD was increased and bone turnover markers were decreased with tamoxifen. BMD and bone turnover changes appeared to stabilise after initial treatment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-11-08.

Adherence and persistence in patients with severe osteoporosis treated with teriparatide

INTRODUCTION

Medical intervention plays a key role in the treatment of postmenopausal osteoporosis and patients' adherence to therapy is essential for optimal clinical outcomes. While adherence in RCTs is usually around 70-90%, a previous study showed that in clinical practice only 27.8% and 46.5% of the women on oral daily vs. weekly alendronate were still on treatment after 12 months. Data on adherence to teriparatide (TPTD) treatment of severe postmenopausal osteoporosis are available from only few countries. This study assessed adherence and persistence with TPTD in Germany.

MATERIAL AND METHODS

A sample of 50 women with severe postmenopausal osteoporosis treated with TPTD in accordance to the German osteoporosis guidelines was included. Treatment was initiated 12-24 months before recruitment. Patient self report was assessed using a validated questionnaire. In addition medication possession ratio (MPR) was calculated by counting prescription refills, and therefore all physicians who were treating the patients for any disease were contacted. Patients were classified adherent at 12 months of therapy if self-reported adherence and an MPR of > or =80% were achieved. Persistence was calculated in months and analysed with a Kaplan-Meier estimate.

RESULTS

Apart from a significantly lower age at menopause in the adherent group (46.1 vs. 50.0; p < 0.006) there were no significant differences in baseline demographics between adherent and non-adherent patients. After 12 months, 80% of the patients treated with TPTD were adherent, while 20% were non-adherent. A significant correlation with treatment adherence was found for self-reported medication tolerability (p < 0.001). Furthermore 79% of patients were persistent after 12 months.

CONCLUSION

These results indicate that more patients seem to be adherent and persistent with TPTD than with oral treatments of postmenopausal osteoporosis. As these patients suffered from severe osteoporosis and sustained several fragility fractures, the generalisability of our retrospective study analysing a small sample is limited. The major factor that reduced adherence and persistence was tolerability. These findings are of practical relevance as numerous studies on antiresorptive therapies have shown that high adherence and persistence were needed to ensure an optimal therapeutic outcome.

Assessment of fracture risk in women with breast cancer using current vs emerging guidelines

Background:

Breast cancer (BC) therapies can have negative effects on bone. Current guidelines recommend antiresorptive therapy based on bone mineral density (BMD), and emerging guidelines include both clinical risk factors and BMD to assess the overall fracture risk. A retrospective, case–controlled study based on current and emerging guidelines was conducted in women with newly diagnosed BC to identify those who were at increased fracture risk based on current and emerging guidelines.

Methods:

Baseline characteristics, fracture risk factors, and lumbar–spine (LS) and total-hip BMD in women with BC (88 premenopausal and 402 postmenopausal) were assessed to determine who would receive bisphosphonate therapy based on current and emerging guidelines.

Results:

Among patients with estrogen-receptor-positive (ER⁺) BC, 18.8% of premenopausal and 36.9% of postmenopausal women were osteopenic at LS. In the postmenopausal cohort, osteoporosis was more prevalent in patients with ER⁺vs ER^– BC. Current guidelines identified 8.9% of patients as eligible for antiresorptive therapy, clinical risk factors alone identified 6.5%, and BMD plus clinical risk factors identified 28.6%.

Conclusions:

In addition to fracture risk factors present at BC diagnosis, cancer therapies leading to BMD loss further increase fracture risk. Evaluating both BMD and clinical risk factors may allow more effective identification of BC patients with elevated fracture risk.

The effect of exemestane or tamoxifen on markers of bone turnover: results of a German sub-study of the Tamoxifen Exemestane Adjuvant Multicentre (TEAM) trial

Adjuvant treatment of breast cancer with aromatase inhibitors has been associated with increased bone loss. In this study, postmenopausal patients with oestrogen receptor positive breast cancer were randomised to exemestane for 5 years or tamoxifen for 2-2.5 years, followed by exemestane for 2-2.5 years. Levels of bone formation markers (bone specific alkaline phosphatase, amino terminal propeptide of type I procollagen, osteocalcin), and the bone resorption marker (carboxyterminal crosslinked telopeptide of type I collagen), were assessed at baseline and after 3, 6 and 12 months of treatment. Exemestane (n=78) resulted in increases from baseline in all bone turnover marker levels at all timepoints. In contrast, levels of all bone marker turnovers decreased with tamoxifen (n=83). Differences between tamoxifen and exemestane were statistically significant for all bone turnover markers at all timepoints. In conclusion, exemestane results in increases in markers of bone formation and resorption, while decreases are observed with tamoxifen.

Fracture risk in women with breast cancer: can baseline assessment of risk be used to guide treatment?

Abstract #6130

Background: Breast cancer (BC) therapies have been associated with decreases in bone health. Recent studies have shown that BC survivors have a 31% increased fracture risk compared with their peers, elevating the importance of monitoring bone health in women diagnosed with BC. Bone mineral density (BMD) has been the standard used by clinical guidelines (WHO, ASCO) to direct therapeutic decisions. However, emerging guidelines place BMD in the context of several other clinical risk factors that have been correlated with overall fracture risk. This retrospective, case-controlled study uses current and emerging guidelines to estimate the percentage of patients with newly diagnosed breast cancer who may be at increased risk for fracture and who require preventive therapy. Methods: Baseline data from 88 pre- and 402 postmenopausal women (PMW) with BC were compared with data from an equal number of healthy age- and body mass index-matched women. BMD was assessed by 2 methods; dual-energy x-ray absorptiometry (DXA) at the lumbar spine (LS) and total hip, and quantitative ultrasonometry (QUS) at the os calcaneus and phalanges. Baseline BMD measurements were collected at a mean duration of 15 and 242 days after diagnosis of cancer in pre- and PMW, respectively. Results: Baseline LS and total hip BMD was similar between the healthy control groups and patients with BC. Among estrogen receptor-positive (ER+) BC patients, 18.8% of premenopausal women and 36.9% of PMW were osteopenic, and 8.9% of PMW were osteoporotic (according to LS BMD). Among ER+ PMW with BC, 15.9% of patients &gt; 65 years of age, 8.3% of patients 55 to 65 years of age, and 1.4% of patients &lt; 55 years of age had osteoporosis. Only 9% of ER+ PMW with BC would have received bone-protective therapy using the BMD limits (T-score ≤ –2.5) set by ASCO treatment guidelines. Based solely on clinical risk factors (eg, if DXA were not available), 6.5% of patients would have been identified for bone-protective therapy. When clinical risk factors and BMD were both used in the fracture-risk assessment, 28.6% of women would have been eligible for bone-protective therapy. Overall, therapy based on ASCO guidelines was estimated to prevent 18% of fractures, whereas combining risk factors and BMD would prevent more than 45% of fractures. Conclusions: Current treatment thresholds seem to inadequately identify patients who would benefit from bone-protective therapy. The results presented here support the use of overall fracture risk assessment in PMW with breast cancer. Using both BMD and clinical risk factors may more effectively identify patients at risk for fracture, although further studies are needed.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6130.

Adherence to adjuvant endocrine therapy in postmenopausal women with breast cancer

BACKGROUND

The level of adherence of various pharmacological therapies in chronic diseases varies, but is predominantly low. With tamoxifen (TAM), 23% and 50% nonadherence after 1 and 4 years have been reported. Day-to-day clinical observation suggests that adherence may even be lower with aromatase inhibitors, but limited data exist on the situation in daily clinical routine. The aim of this study was to evaluate the rate of adherent patients in a randomly selected sample of postmenopausal women with primary breast cancer, who had been assigned to an adjuvant endocrine treatment with TAM or anastrozole (ANA).

MATERIALS AND METHODS

We investigated a random sample of 100 postmenopausal women with breast cancer (50 TAM and 50 ANA) who had received surgery for their primary breast cancer at our hospital in 2004/2005 and thereafter had been assigned to an adjuvant endocrine treatment. We evaluated the adherence rate with a detailed questionnaire and additionally carried out a retrospective prescription check of the hospital chart as well as calling the local physicians of our patients. A patient was counted as adherent with a self-reported tablet intake of 80% or more and if a medication possession ratio of 80% or more was achieved.

RESULTS

Regarding the baseline characteristics, a significant difference in mean age was noticed in women on ANA versus TAM [65 (+/-3) and 72 (+/-3); P<0.001]. All women on TAM and ANA reported to be adherent (100%). After controlling for prescriptions, only 40 (80%) and 27 (69%) of the women on TAM and ANA were still classified as adherent (P<0.01 and P<0.01 versus self-report). We found no significant correlation of adherence to any baseline characteristics or side-effects in a logistic regression model.

CONCLUSIONS

An important goal of any therapeutic intervention is to achieve comparable efficacy in routine clinical practice to that demonstrated in randomised clinical trials. However, a similar magnitude of adherence will be necessary in routine clinical practice to assure comparable clinical effects. Our results further support the data on suboptimal adherence of women with breast cancer on adjuvant TAM treatment. Here, we evaluated for the first time the patient reported and real-world adherence on adjuvant ANA and were able to show a similarly low adherence compared with TAM. More prospective studies are needed to increase our understanding of the underlying reasons for nonadherence in women with breast cancer.

Bone effects of exemestane vs. tamoxifen within the TEAM trial: results of a prospective randomized bone sub study

Abstract #1143

Background: A prospective open label randomized multicenter trial was performed in the German TEAM Trial Group to compare the effects of the steroidal aromatase inhibitor Exemestane (EXE) and the ER agonist/antagonist Tamoxifen (TAM) on bone mineral density (BMD) and markers of bone turnover during adjuvant treatment of postmenopausal women with estrogen receptor positive breast cancer.&#x2028; Methods: 200 postmenopausal estrogen receptor positive breast cancer women&#x2028; were included in the bone substudy. Women with a history of osteoporosis or a disease or treatment known to effect bone metabolism were excluded. BMD and markers of bone turnover were assessed at baseline, after 6 and 12 months of treatment. BMD was performed using dual x-ray absorptiometry (DXA) at the lumber spine and femoral neck (FN). Marker of bone formation, PINP, bone specific alkaline phosphatase (BAP) and osteocalcin (OC) as well as bone resorption marker (ICPM) were analysed using standardised methods. Intent-to-treat analysis was performed based on 200 patients. The primary endpoint was to compare Exemestane and Tamoxifen with regard to changes from baseline to month 12 in BMD (g/cm²) in lumbar spine (integral of L1-L4). Results: 156 patients with a mean age of 61 yr. (+/- 7.3 yr.) were available for final analysis. Both groups were comparable regarding age, height, tumor grade and stage. Compared to women on Tamoxifen, who comprised an BMD increase of +0.9% and +0.9% after 6 and 12 months at the spine, women on EXE showed a decrease of -2.8% and -3.6%. Conversely, BMD at the FN showed a decrease of -2.1% and -2.2% in women on TAM while women on EXE showed a decrease of -3.4% after 6 and an increase of +1.1% after 12 months, respectivly. Bone formation and absorption was modulated in both groups. Details will be presented at the meeting.Conclusion: The results of the 12 months analysis in the TEAM Bone substudy confirm the bone protective effect of TAM at the spine while conversely the results at the FN showed a decrease. Women on EXE showed a decrease at the spine while there was a neutral effect at the FN. Futher evaluation of the 24 months data as well as the fracture rate of the total TEAM trial are nessecary to evaluate the effect of EXE on bone health.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1143.