Gut-associated lymphoid tissue attrition associates with response to anti-α4β7 therapy in ulcerative colitis

Vedolizumab (VDZ) is a first-line treatment in ulcerative colitis (UC) that targets the α4β7- mucosal vascular addressin cell adhesion molecule 1 (MAdCAM-1) axis. To determine the mechanisms of action of VDZ, we examined five distinct cohorts of patients with UC. A decrease in naïve B and T cells in the intestines and gut-homing (β7+) plasmablasts in circulation of VDZ-treated patients suggested that VDZ targets gut-associated lymphoid tissue (GALT). Anti-α4β7 blockade in wild-type and photoconvertible (KikGR) mice confirmed a loss of GALT size and cellularity because of impaired cellular entry. In VDZ-treated patients with UC, treatment responders demonstrated reduced intestinal lymphoid aggregate size and follicle organization and a reduction of β7+IgG+ plasmablasts in circulation, as well as IgG+ plasma cells and FcγR-dependent signaling in the intestine. GALT targeting represents a previously unappreciated mechanism of action of α4β7-targeted therapies, with major implications for this therapeutic paradigm in UC.

Weakened APC/C activity at mitotic exit drives cancer vulnerability to KIF18A inhibition

The efficacy of current antimitotic cancer drugs is limited by toxicity in highly proliferative healthy tissues. A cancer-specific dependency on the microtubule motor protein KIF18A therefore makes it an attractive therapeutic target. Not all cancers require KIF18A, however, and the determinants underlying this distinction remain unclear. Here, we show that KIF18A inhibition drives a modest and widespread increase in spindle assembly checkpoint (SAC) signaling from kinetochores which can result in lethal mitotic delays. Whether cells arrest in mitosis depends on the robustness of the metaphase-to-anaphase transition, and cells predisposed with weak basal anaphase-promoting complex/cyclosome (APC/C) activity and/or persistent SAC signaling through metaphase are uniquely sensitive to KIF18A inhibition. KIF18A-dependent cancer cells exhibit hallmarks of this SAC:APC/C imbalance, including a long metaphase-to-anaphase transition, and slow mitosis overall. Together, our data reveal vulnerabilities in the cell division apparatus of cancer cells that can be exploited for therapeutic benefit.

Small-molecule inhibition of kinesin KIF18A reveals a mitotic vulnerability enriched in chromosomally unstable cancers

Chromosomal instability (CIN) is a hallmark of cancer, caused by persistent errors in chromosome segregation during mitosis. Aggressive cancers like high-grade serous ovarian cancer (HGSOC) and triple-negative breast cancer (TNBC) have a high frequency of CIN and TP53 mutations. Here, we show that inhibitors of the KIF18A motor protein activate the mitotic checkpoint and selectively kill chromosomally unstable cancer cells. Sensitivity to KIF18A inhibition is enriched in TP53-mutant HGSOC and TNBC cell lines with CIN features, including in a subset of CCNE1-amplified, CDK4-CDK6-inhibitor-resistant and BRCA1-altered cell line models. Our KIF18A inhibitors have minimal detrimental effects on human bone marrow cells in culture, distinct from other anti-mitotic agents. In mice, inhibition of KIF18A leads to robust anti-cancer effects with tumor regression observed in human HGSOC and TNBC models at well-tolerated doses. Collectively, our results provide a rational therapeutic strategy for selective targeting of CIN cancers via KIF18A inhibition.

Vision difficulty and dementia: economic hardships among older adults and their caregivers

Introduction

Limited research has examined the economic impact of vision difficulty (VD) and dementia on older adults and their caregivers. We aimed to determine whether older adults with VD and/or dementia, and their caregivers, face more economic hardships than their counterparts without VD or dementia.

Methods

We used cross-sectional data from the 2015 National Health and Aging Trends Study (NHATS), a population-based survey of Medicare beneficiaries, linked to their family/unpaid caregivers from the National Study of Caregiving (NSOC). Regression models characterized the association of VD (self-report), dementia (survey and cognitive assessments), and co-occurring VD and dementia with debt, receiving financial help from relatives, government-based Supplemental Nutrition Assistance Program (SNAP), other food assistance, utility assistance, and caregiver financial difficulty.

Results

The NHATS sample included 6,879 community-dwelling older adults (5670 no VD/dementia, 494 VD-alone, 512 dementia-alone, 203 co-occurring VD and dementia). Adults with VD and dementia had higher odds of receiving SNAP benefits (OR = 2.6, 95%CI = 1.4-4.8) and other food assistance (OR = 4.1, 95%CI = 1.8-9.1) than adults without VD/dementia, while no differences were noted for debt, financial help, and utility assistance. Adults with VD-alone had higher odds of debt (OR = 2.1, 95%CI = 1.3-3.2), receiving financial help (OR = 1.7, 95%CI = 1.1-2.5) and other food assistance (OR = 2.7, 95%CI = 1.7-4.3); while adults with dementia-alone had higher odds of debt (OR = 2.8, 95%CI = 1.4-5.5). The NSOC sample included 1,759 caregivers (995 caring for adults without VD/dementia, 223 for VD-alone, 368 for dementia-alone, and 173 for co-occurring VD and dementia). Compared to caregivers of older adults without VD/dementia, caregivers of adults with VD and dementia had higher odds of financial difficulty (OR = 3.0, 95%CI = 1.7-5.3) while caregivers of adults with VD-alone or dementia-alone did not.

Discussion

While older adults with VD- or dementia-alone experienced increased economic hardships, disparities in food assistance were amplified among older adults with co-occurring disease. Caregivers of adults with co-occurring disease experienced more financial difficulty than caregivers of adults with a single or no disease. This study highlights the need for interventions across clinical and social services to support the economic wellbeing of our aging population and their caregivers.

Sex Differences in Pancreatic β-Cell Physiology and Glucose Homeostasis in C57BL/6J Mice

The importance of sexual dimorphism has been highlighted in recent years since the National Institutes of Health's mandate on considering sex as a biological variable. Although recent studies have taken strides to study both sexes side by side, investigations into the normal physiological differences between males and females are limited. In this study, we aimed to characterized sex-dependent differences in glucose metabolism and pancreatic β-cell physiology in normal conditions using C57BL/6J mice, the most common mouse strain used in metabolic studies. Here, we report that female mice have improved glucose and insulin tolerance associated with lower nonfasted blood glucose and insulin levels compared with male mice at 3 and 6 months of age. Both male and female animals show β-cell mass expansion from embryonic day 17.5 to adulthood, and no sex differences were observed at embryonic day 17.5, newborn, 1 month, or 3 months of age. However, 6-month-old males displayed increased β-cell mass in response to insulin resistance compared with littermate females. Molecularly, we uncovered sexual dimorphic alterations in the protein levels of nutrient sensing proteins O-GlcNAc transferase and mTOR, as well as differences in glucose-stimulus coupling mechanisms that may underlie the differences in sexually dimorphic β-cell physiology observed in C57BL/6J mice.

The state of the pediatric HIV epidemic in Lesotho

OBJECTIVE

Lesotho does not have reliable data on HIV prevalence in children, relying on estimates generated from program data. The 2016 Lesotho Population-based HIV Impact Assessment (LePHIA) aimed to determine HIV prevalence among children 0-14 years to assess the effectiveness of the prevention of mother-to-child transmission (PMTCT) program and guide future policy.

METHODS

A nationally representative sample of children under 15 years underwent household-based, two-stage HIV testing from November 2016-May 2017. Children <18 months with a reactive screening test were tested for HIV infection using total nucleic acid (TNA) PCR. Parents (61.1%) or legal guardians (38.9%) provided information on children's clinical history. Children aged 10-14 years also answered a questionnaire on knowledge and behaviors.

RESULTS

HIV prevalence was 2.1% [95% confidence interval (CI): 1.5-2.6]. Prevalence in 10-14 year olds (3.2%; 95% CI: 2.1, 4.2) was significantly greater compared to 0-4 year olds (1.0%; 95% CI: 0.5, 1.6). HIV prevalence in girls and boys was 2.6% (95% CI: 1.8-3.3) and 1.5% (95% CI: 1.0-2.1), respectively. Based on reported status and/or the presence of detectable antiretrovirals, 81.1% (95% CI: 71.7-90.4) of HIV-positive children were aware of their status, 98.2% (95% CI: 90.7-100.0) of those aware were on antiretroviral therapy (ART) and 73.9% (95% CI: 62.1-85.8) of those on ART were virally suppressed.

CONCLUSIONS

Despite the roll-out of Option B+ in Lesotho in 2013, pediatric HIV prevalence remains high. Further research is required to understand the greater prevalence among girls, barriers to PMTCT, and how to better achieve viral suppression in children with HIV.

Gut-associated lymphoid tissue attrition associates with response to anti-α4β7 therapy in ulcerative colitis

Targeting the α4β7-MAdCAM-1 axis with vedolizumab (VDZ) is a front-line therapeutic paradigm in ulcerative colitis (UC). However, mechanism(s) of action (MOA) of VDZ remain relatively undefined. Here, we examined three distinct cohorts of patients with UC (n=83, n=60, and n=21), to determine the effect of VDZ on the mucosal and peripheral immune system. Transcriptomic studies with protein level validation were used to study drug MOA using conventional and transgenic murine models. We found a significant decrease in colonic and ileal naïve B and T cells and circulating gut-homing plasmablasts (β7+) in VDZ-treated patients, pointing to gut-associated lymphoid tissue (GALT) targeting by VDZ. Murine Peyer's patches (PP) demonstrated a significant loss cellularity associated with reduction in follicular B cells, including a unique population of epithelium-associated B cells, following anti-α4β7 antibody (mAb) administration. Photoconvertible (KikGR) mice unequivocally demonstrated impaired cellular entry into PPs in anti-α4β7 mAb treated mice. In VDZ-treated, but not anti-tumor necrosis factor-treated UC patients, lymphoid aggregate size was significantly reduced in treatment responders compared to non-responders, with an independent validation cohort further confirming these data. GALT targeting represents a novel MOA of α4β7-targeted therapies, with major implications for this therapeutic paradigm in UC, and for the development of new therapeutic strategies.

Interactions between the apolipoprotein E4 gene and modifiable risk factors for cognitive impairment: a nationally representative panel study

BACKGROUND

Few studies using rigorous clinical diagnosis have considered whether associations with cognitive decline are potentiated by interactions between genetic and modifiable risk factors. Given the increasing burden of cognitive impairment (CI) and dementia, we assessed whether Apolipoprotein E ε4 (APOE4) genotype status modifies the association between incident CI and key modifiable risk factors .

METHODS

Older adults (70+) in the US were included. APOE4 status was genotyped. Risk factors for CI were self-reported. Cognitive status (normal, CI, or dementia) was assigned by clinical consensus panel. In eight separate Cox proportional hazard models, we assessed for interactions between APOE4 status and other CI risk factors.

RESULT

The analytical sample included 181 participants (mean age 77.7 years; 45.9% male). APOE4 was independently associated with a greater hazard of CI in each model (Hazard Ratios [HR] between 1.81-2.66, p < 0.05) except the model evaluating educational attainment (HR 1.65, p = 0.40). The joint effects of APOE4 and high school education or less (HR 2.25, 95% CI: 1.40-3.60, p < 0.001), hypertension (HR 2.46, 95% CI: 1.28-4.73, p = 0.007), elevated depressive symptoms (HR 5.09, 95% CI: 2.59-10.02, p < 0.001), hearing loss (HR 3.44, 95% CI: 1.87-6.33, p < 0.0001), vision impairment (HR 5.14, 95% CI: 2.31-11.43, p < 0.001), smoking (HR 2.35, 95% CI: 1.24-4.47, p = 0.009), or obesity (HR 3.80, 95% CI: 2.11-6.85, p < 0.001) were associated with the hazard of incident CIND (compared to no genetic or modifiable risk factor) in separate models. The joint effect of Apolipoprotein ε4 and type 2 diabetes was not associated with CIND (HR 1.58, 95% CI: 0.67-2.48, p = 0.44).

DISCUSSION

The combination of APOE4 and selected modifiable risk factors conveys a stronger association with incident CI than either type of risk factor alone.

Abstract LB202: Discovery and preclinical characterization of novel small molecule inhibitors of kinesin KIF18A motor protein with potent activity against chromosomally unstable cancers

KIF18A is a mitotic kinesin that localizes to the plus-end tips of kinetochore microtubule (MT) spindle fibers during metaphase, where it regulates chromosome alignment, and promotes the viability of chromosomally unstable cancer cells. KIF18A is overexpressed in a subset of human cancers, and its elevated expression is associated with tumor aggressiveness.

Chromosomal instability (CIN) is a hallmark of human cancers and is caused by persistent errors in chromosome segregation during mitosis. Aggressive types of human cancer such as high-grade serous ovarian cancer (HGSOC) and triple-negative breast cancer (TNBC) have elevated levels of CIN and frequently harbor alterations in TP53 tumor suppressor gene. These two CIN+ cancer subtypes share molecular similarities but have limited treatment options at present. The rationale of pharmacological inhibition of KIF18A motor activity is to selectively target a tumor-specific mitotic spindle vulnerability in CIN+ cancer cells while largely sparing normal diploid dividing somatic cells.

Here, we describe the identification of a novel series of potent and selective small molecule inhibitors of KIF18A MT-ATPase motor activity exemplified by AM-1882, that disrupt the mitotic spindle and selectively kill chromosomally unstable cancer cells. Our KIF18A inhibitors phenocopy genetic ablation of KIF18A and trigger spindle assembly checkpoint activation, multipolarity, and apoptosis in sensitive CIN+ cancer cell lines. The sensitivity profile of AM-1882 is focal-in-nature with cell potency in the low double-digit nanomolar range across a panel of breast and ovarian cancer cell lines, including lines that harbor genetic alterations (e.g., TP53, CCNE1, RB1, BRCA1, whole genome doubling) frequently enriched in CIN+ cancers and in HGSOC and TNBC tumor subtypes. Furthermore, the sensitivity profile of AM-1882 is distinct from comparator test agents ispinesib (Eg5, pan cytotoxic) and palbociclib (CDK4/6, focal cytostatic). The combination of AM-1882 with PARP inhibitor olaparib is synergistic in BRCA1-deficient cancer cell lines, with evidence of increased double-strand DNA breaks (p-H2AX) and apoptosis (cl-PARP). Importantly, KIF18A inhibitors have minimal toxicity on normal dividing somatic cell types in vitro, including proliferating human bone marrow mononuclear cells, distinct from paclitaxel and small molecule inhibitors of essential mitotic kinases and kinesins. In vivo, we demonstrate that administration of KIF18A inhibitors AM-1882 and AM-5308 induce a robust pharmacodynamic response (pH3, mitotic marker) and frank tumor regressions in two TP53 mutant human HGSOC xenograft models (OVCAR-3, OVCAR-8) at well-tolerated doses.

Collectively, our preclinical data provides the first example of a therapeutic strategy to selectively target CIN+ cancers through inhibition of KIF18A motor protein.

Citation Format: Jan Sun, Brain Belmontes, Jodi Moriguchi, Grace Chung, Kui Chen, John D. McCarter, Upendra P. Dahal, Andrew S. Boghossian, Matthew G. Rees, Melissa M. Ronan, Jennifer A. Roth, Sheroy Minocherhomji, Matthew P. Bourbeau, Jennifer R. Allen, Angela Coxon, Paul E. Hughes, Nuria Tamayo, Marc N. Payton. Discovery and preclinical characterization of novel small molecule inhibitors of kinesin KIF18A motor protein with potent activity against chromosomally unstable cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB202.

Association between EAT-Lancet Diet Index and Hypertension Prevalence: The Filipino Women's Diet and Health Study (FiLWHEL)

Objectives

We examined the association between adherence to EAT-Lancet diet, a diet with human health and environmental sustainability, and the prevalence of hypertension among Filipino immigrant women in Korea.

Methods

We included a total of 484 Filipino women aged 34–57 in the Filipino Women's Diet and Health Study (FiLWHEL). Participants' dietary intakes were assessed using the 24-hour recalls in 2014–2016. The EAT-Lancet diet index scores were calculated using the methods used in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Oxford study (EAT-Lancet EPIC) and Malmö Diet and Cancer Cohort Study (EAT-Lancet Malmö). Blood pressures were measured twice by a sphygmomanometer, and two readings were averaged. Hypertension was defined as systolic blood pressure (SBP) ≥140 mmHg or diastolic blood pressure (DBP) ≥90 mmHg or by taking antihypertensive medication. We calculated odds ratio (OR)s and 95% confidence interval (CI)s using the multivariate logistic regression models.

Results

A total of 86 hypertensive women were identified. For the EAT-Lancet EPIC index, compared with the 1st tertile, ORs (95% CIs) for hypertension were 1.03(0.52–2.06) for the 2nd tertile and 0.61 (0.30–1.22) for the 3rd tertile (p-trend = 0.17). For the EAT-Lancet Malmö index, compared with the 1st tertile, ORs (95% CIs) for hypertension were 0.44 (0.21–0.89) for the 2nd tertile and 0.77(0.37–1.60) for the 3rd tertile (p for trend = 0.55).

Conclusions

Adherence to the EAT-Lancet diet may be associated with a lower prevalence of hypertension among immigrant Filipino women in Korea. Further prospective and intervention studies are warranted to determine the role of a sustainable EAT-Lancet diet in hypertension prevention.

Funding Sources

This study was made possible with the support of our funding agencies: Hanmi Pharmaceutical Co., Ltd., Chong Kun Dang Pharm., Handok Inc., and Yuhan Corporation, Seoul, Korea.

Targeting the Mitotic Kinesin KIF18A in Chromosomally Unstable Cancers: Hit Optimization Toward an In Vivo Chemical Probe

Chromosomal instability (CIN) is a hallmark of cancer that results from errors in chromosome segregation during mitosis. Targeting of CIN-associated vulnerabilities is an emerging therapeutic strategy in drug development. KIF18A, a mitotic kinesin, has been shown to play a role in maintaining bipolar spindle integrity and promotes viability of CIN cancer cells. To explore the potential of KIF18A, a series of inhibitors was identified. Optimization of an initial hit led to the discovery of analogues that could be used as chemical probes to interrogate the role of KIF18A inhibition. Compounds 23 and 24 caused significant mitotic arrest in vivo, which was sustained for 24 h. This would be followed by cell death either in mitosis or in the subsequent interphase. Furthermore, photoaffinity labeling experiments reveal that this series of inhibitors binds at the interface of KIF18A and tubulin. This study represents the first disclosure of KIF18A inhibitors with in vivo activity.

Antioxidant potential and α-glucosidase inhibitory activity of onion (Allium cepa L.) peel and bulb extracts

Allium cepa L. is a commonly consumed vegetable that belongs to the Amaryllidaceae family and contains nutrients and antioxidants in ample amounts. In spite of the valuable food applications of onion bulb, its peel and outer fleshy layers are generally regarded as waste and exploration of their nutritional and therapeutic potential is still in progress with a very slow progression rate. The present study was designed with the purpose of doing a comparative analysis of the antioxidant potential of two parts of Allium cepa, i.g., bulb (edible part) and outer fleshy layers and dry peels (inedible part). Moreover, the inhibitory effect of the onion bulb and peel extracts on rat intestinal α-glucosidase and pancreatic α-amylase of porcine was also evaluated. The antioxidant potential of onion peel and bulb extracts were evaluated using 2,2-diphenyl- 1-picryl hydrazyl (DPPH), ferric-reducing antioxidant power assay (FRAP), 2,2'-azino-bis- 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay, H2O2 radical scavenging activity and Fe2+ chelating activity. Total flavonoids and phenolic content of ethanolic extract of onion peel were significantly greater as compared to that of onion bulb. Ethanolic extract of onion peel also presented better antioxidant and free-radical scavenging activity as compared to the ethanolic extract of bulb, while the aqueous extract of bulb presented weakest antioxidative potential. Onion peel extract's α-glucosidase inhibition potential was also correlated with their phenolic and flavonoid contents. The current findings presented onion peel as a possible source of antioxidative agents and phenolic compounds that might be beneficial against development of various common chronic diseases that might have an association with oxidative stress. Besides, outer dry layers and fleshy peels of onion exhibited higher phenolic content and antioxidant activities, compared to the inner bulb. The information obtained by the present study can be useful in promoting the use of vegetable parts other than the edible mesocarp for several future food applications, rather than these being wasted.

Improving preprocedure antithrombotic management: Implementation and sustainment of a best practice alert and pharmacist referral process

BACKGROUND

Electronic medical record-based interventions such as best practice alerts, or reminders, have been proposed to improve evidence-based medication prescribing. Formal implementation evaluation including long-term sustainment are not commonly reported. Preprocedural medication management is often a complex issue for patients taking antithrombotic medications.

METHODS

We implemented a best practice alert (BPA) that recommended referral to an anticoagulation clinic before outpatient elective gastrointestinal (GI) endoscopies. Eligible patients were taking an oral anticoagulant (warfarin or direct oral anticoagulant [DOAC]) and/or antiplatelet medications. Patients referred to the anticoagulation clinic were compared to those managed by the ordering provider. Outcomes assessed included guideline-adherent drug management before endoscopy, documentation of a medication management plan, guideline-adherent rates of bridging for high-risk patients taking warfarin, and evaluation for sustained use of BPA.

RESULTS

Eighty percent of patients (553/691) were referred to the anticoagulation clinic during the initial 13-month study period. Most referrals came from gastroenterologists (397/553; 71.8%) followed by primary care providers (127/554; 22.9%). Patients referred had improved rates of guideline-adherent medication management compared to those who were not referred (97.4% vs 91.0%; P = .001). Documentation of medication plan was significantly higher in the referred group (99.1% vs 59.4%; P ≤ .001). There were no differences in rates of appropriate bridging for patients taking warfarin. Implementation of the BPA also resulted in sustained, consistent use over an additional 18 months following the initial study period.

CONCLUSION

Implementation of a BPA before elective outpatient GI endoscopies was associated with improved rates of guideline-adherent medication management and documented management plan, while streamlining preprocedural medication management.

Clinical validation of a targeted methylation-based multi-cancer early detection test using an independent validation set

BACKGROUND

A multi-cancer early detection (MCED) test used to complement existing screening could increase the number of cancers detected through population screening, potentially improving clinical outcomes. The Circulating Cell-free Genome Atlas study (CCGA; NCT02889978) was a prospective, case-controlled, observational study and demonstrated that a blood-based MCED test utilizing cell-free DNA (cfDNA) sequencing in combination with machine learning could detect cancer signals across multiple cancer types and predict cancer signal origin (CSO) with high accuracy. The objective of this third and final CCGA substudy was to validate an MCED test version further refined for use as a screening tool.

PATIENTS AND METHODS

This pre-specified substudy included 4077 participants in an independent validation set (cancer: n = 2823; non-cancer: n = 1254, non-cancer status confirmed at year-one follow-up). Specificity, sensitivity, and CSO prediction accuracy were measured.

RESULTS

Specificity for cancer signal detection was 99.5% [95% confidence interval (CI): 99.0% to 99.8%]. Overall sensitivity for cancer signal detection was 51.5% (49.6% to 53.3%); sensitivity increased with stage [stage I: 16.8% (14.5% to 19.5%), stage II: 40.4% (36.8% to 44.1%), stage III: 77.0% (73.4% to 80.3%), stage IV: 90.1% (87.5% to 92.2%)]. Stage I-III sensitivity was 67.6% (64.4% to 70.6%) in 12 pre-specified cancers that account for approximately two-thirds of annual USA cancer deaths and was 40.7% (38.7% to 42.9%) in all cancers. Cancer signals were detected across >50 cancer types. Overall accuracy of CSO prediction in true positives was 88.7% (87.0% to 90.2%).

CONCLUSION

In this pre-specified, large-scale, clinical validation substudy, the MCED test demonstrated high specificity and accuracy of CSO prediction and detected cancer signals across a wide diversity of cancers. These results support the feasibility of this blood-based MCED test as a complement to existing single-cancer screening tests.

CLINICAL TRIAL NUMBER

NCT02889978.

Association of Dietary Branched-Chain Amino Acids With Obesity: The Filipino Women's Diet and Health Study (FiLWHEL)

Objectives

Migration plays a significant role in dietary choices and health of populations. Studies on dietary intakes of branched-chain amino acids (BCAA) and health status of migrant populations are scarce. This study examined the association between dietary BCAA intake and risk of obesity among migrant Filipino women in Korea.

Methods

This study included 428 women (20–57years) enrolled in the FiLWHEL study. Demographic information and anthropometric measurements (weight and height) were obtained using a standard protocol. Dietary BCAA (isoleucine, leucine, and valine) intakes were derived from a one-day 24-hour dietary recall. Body mass index (BMI) was calculated from weight and height. Obesity was defined as BMI ≥ 25 kg/m2. Energy-adjusted BCAA intakes were categorized in quartile distribution with the lowest quartile as a reference and multivariable-adjusted odds ratio (OR) with 95% confidence interval (CI) of obesity risk were estimated using logistic regression at a statistical significance of P &lt; 0.05.

Results

Mean age and BMI were 35.0 ± 8.1 years and 23.6 ± 3.9 kg/m2 respectively. 30.8% had BMI ≥ 25 kg/m2. Also, median and interquartile range of BCAA intakes (mg/day) were isoleucine: 1920.9 (1231.9–2719.1), leucine: 3318.9 (2134.2–4774.1), valine: 2257.3 (1442.6–3283.1) and total BCAA: 7519.0 (4762.0–10,726.9). Multivariable-adjusted OR and 95% CI for obesity risk given dietary BCAA intakes for each subsequent quartile compared to the bottom quartile were; isoleucine: 0.48 (0.27–0.89), 0.67 (0.37–1.02), and 0.49 (0.27–0.89) P for trend = 0.09; leucine: 0.69 (0.37–1.28), 0.80 (0.44–1.46), and 0.62 (0.34–1.13) P for trend = 0.23; valine: 0.51 (0.27–0.95), 0.77 (0.43–1.37), and 0.52 (0.28–0.95) P for trend = 0.15 and total BCAA: 0.58 (0.31–1.09), 0.82 (0.45–1.48), and 0.56 (0.31–1.03) P for trend = 0.23.

Conclusions

Dietary BCAA intake appears inversely related to the odds of obesity in this sample of Filipino migrants in Korea. Cohort studies among migrant population might significantly benefit the validation of these observations.

Funding Sources

This work was supported by the Hanmi Pharmaceutical Co., Ltd, (No. 201300000001270), Chong Kun Dang Pharm. Seoul, Korea (No. 201600000000225) and the Brain Pool Program through the National Research Foundation of Korea funded by the Ministry of Science and ICT (No. 2020H1D3A1A04081265).

Pharmacy stakeholder reports on ethical and logistical considerations in anti-opioid vaccine development

BACKGROUND

As opioid use disorder (OUD) incidence and its associated deaths continue to persist at elevated rates, the development of novel treatment modalities is warranted. Recent strides in this therapeutic area include novel anti-opioid vaccine approaches. This work compares logistical and ethical considerations surrounding currently available interventions for opioid use disorder with an anti-opioid vaccine approach.

METHODS

The opinions of student pharmacists and practicing pharmacists assessing knowledge, perceptions, and attitudes toward current and future OUD management strategies were characterized using a staged, multi-modal research approach incorporating a focus group, pilot survey development and refinement, and final survey deployment. Survey responses were assessed using one- and two-way parametric and non-parametric analyses where appropriate, and multi-dimensional matrix profiles were compared using z-tests following an exhaustive combinatorial sum of differences calculation between items within each compared matrix.

RESULTS

Focus group content analysis revealed a high level of agreeableness among participants regarding anti-opioid vaccine technology and a sense of shared ownership regarding solutions to the opioid epidemic at large. Pilot survey results demonstrated subject ability to consider both pragmatic and ethical considerations related to current therapeutics and novel interventions in a single instrument, with high endurance amongst engaged subjects. Access inequality was the most concerning ethical consideration identified for anti-opioid vaccines. Support for anti-opioid vaccine implementation across various clinical scenarios was strongest for voluntary use amongst individuals in recovery, and lowest for mandatory use in at-risk individuals.

CONCLUSIONS

Ethical and logistical concerns surrounding anti-opioid vaccines were largely similar to those for current OUD therapeutics overall. Anti-opioid vaccines were endorsed as helpful potential additions to current OUD therapeutic approaches, particularly for voluntary use in the later stages of clinical progression.

Gestational Diabetes Mellitus: A Harbinger of the Vicious Cycle of Diabetes

Gestational diabetes mellitus (GDM), characterized by a transitory form of diabetes induced by insulin resistance and pancreatic β-cell dysfunction during pregnancy, has been identified as one of the major obstacles in achieving improved maternal and child health. Approximately 9-25% of pregnancies worldwide are impacted by the acute, long-term, and transgenerational health complications of this disease. Here, we discuss how GDM affects longstanding maternal and neonatal outcomes, as well as health risks that likely persist into future generations. In addition to the current challenges in the management and diagnosis of and the complications associated with GDM, we discuss current preclinical models of GDM to better understand the underlying pathophysiology of the disease and the timely need to increase our scientific toolbox to identify strategies to prevent and treat GDM, thereby advancing clinical care.

Role of nutrient-driven O-GlcNAc-post-translational modification in pancreatic exocrine and endocrine islet development

Although the developing pancreas is exquisitely sensitive to nutrient supply in utero, it is not entirely clear how nutrient-driven post-translational modification of proteins impacts the pancreas during development. We hypothesized that the nutrient-sensing enzyme O-GlcNAc transferase (Ogt), which catalyzes an O-GlcNAc-modification onto key target proteins, integrates nutrient-signaling networks to regulate cell survival and development. In this study, we investigated the heretofore unknown role of Ogt in exocrine and endocrine islet development. By genetic manipulation in vivo and by using morphometric and molecular analyses, such as immunofluorescence imaging and single cell RNA sequencing, we show the first evidence that Ogt regulates pancreas development. Genetic deletion of Ogt in the pancreatic epithelium (OgtKOPanc) causes pancreatic hypoplasia, in part by increased apoptosis and reduced levels of of Pdx1 protein. Transcriptomic analysis of single cell and bulk RNA sequencing uncovered cell-type heterogeneity and predicted upstream regulator proteins that mediate cell survival, including Pdx1, Ptf1a and p53, which are putative Ogt targets. In conclusion, these findings underscore the requirement of O-GlcNAcylation during pancreas development and show that Ogt is essential for pancreatic progenitor survival, providing a novel mechanistic link between nutrients and pancreas development.

Alzheimer's disease: insights for risk evaluation and prevention in the Chinese population and the need for a comprehensive programme in Hong Kong/China

With the ageing of the global population, China is projected to be impacted significantly by the rising number of patients with Alzheimer's disease (AD). A cure for AD is not yet available, so society should be prepared for an increasing AD-related burden. In this review, we examine this impending problem and provide overviews on (a) the magnitude of the problem of AD in Hong Kong/China in the near future; (b) the genetic and lifestyle risk factors that contribute to AD; (c) current diagnostic approaches and the potential of newly discovered genetic biomarkers for early detection; (d) medications, non-pharmacological interventions, and possible preventive measures; and (e) the need for social and psychological care from the community. In Hong Kong, primary care and AD-related support for at-risk individuals, patients, and caregivers are inadequate. A joint effort from the medical community, government, universities, non-governmental organisations/charities, and industry should initiate the development of a long-term programme for AD. Finally, we outline recommendations for the relevant parties to consider.

Pigs that recover from porcine reproduction and respiratory syndrome virus infection develop cytotoxic CD4+CD8+ and CD4+CD8- T-cells that kill virus infected cells

Porcine reproductive and respiratory syndrome virus (PRRSV) infection is difficult to control because the virus undergoes antigenic variation during infection and also modulates the protective host immune response. Although current vaccines do not provide full protection, they have provided insight into the mechanisms of protection. Live PRRSV vaccines induce partial protection before the appearance of neutralizing antibody, suggesting cell-mediated immunity or other mechanisms may be involved. Herein, we demonstrate recovery from infection is associated with development of cytotoxic T-lymphocytes (CTL) that can kill PRRSV-infected target cells. Initial experiments showed survival of PRRSV-infected monocyte derived macrophage (MDM) targets is reduced when overlaid with peripheral blood mononuclear cells (PBMC) from gilts that had recovered from PRRSV infection. Further studies with PBMC depleted of either CD4⁺ or CD8⁺ T-cells and positively selected subpopulations of CD4⁺ and CD8⁺ T-cells showed that both CD4⁺ and CD8⁺ T-cells were involved in killing. Examination of killing at different time points revealed killing was biphasic and mediated by CTL of different phenotypes. CD4⁺CD8^+high were associated with killing target cells infected for 3–6 hours. CD4⁺CD8^- CTL were associated with killing at 16–24 hours. Thus, all the anti-PRRSV CTL activity in pigs was attributed to two phenotypes of CD4⁺ cells which is different from the anti-viral CD4^-CD8⁺ CTL phenotype found in most other animals. These findings will be useful for evaluating CTL responses induced by current and future vaccines, guiding to a novel direction for future vaccine development.

A novel modified-indirect ELISA based on spherical body protein 4 for detecting antibody during acute and long-term infections with diverse Babesia bovis strains

Background

Cattle persistently infected with Babesia bovis are reservoirs for intra- and inter-herd transmission. Since B. bovis is considered a persistent infection, developing a reliable, high-throughput assay that detects antibody during all stages of the infection could be pivotal for establishing better control protocols.

Methods

A modified indirect enzyme-linked immunosorbent assay (MI-ELISA) was developed using the spherical body protein-4 (SBP4) of B. bovis to detect antibody against diverse strains through all infection stages in cattle. This SBP4 MI-ELISA was evaluated for sensitivity and specificity against field sera from regions with endemic and non-endemic B. bovis. Sera were also evaluated from cattle infected experimentally with various doses and strains during acute and persistent infection with parasitemia defined by nested PCR.

Results

The format variables for SBP4 MI-ELISA were optimized and the cutoff for positive and negative interpretation was determined based on receiver operating characteristic curve analysis using B. bovis positive and negative sera tested in the reference immunofluorescence assay (IFA). The diagnostic specificity of the SBP4 MI-ELISA using IFA-negative sera collected from Texas was 100%, significantly higher than the cELISA (90.4%) based on an epitope in the rhoptry-associated protein-1 (RAP-1 cELISA). The diagnostic sensitivity of the SBP4 MI-ELISA was 98.7% using the IFA-positive sera collected from several areas of Mexico, in contrast to that of the RAP-1 cELISA at 60% using these same sera. In cattle infected with low and high doses of three B. bovis strains, the SBP4 MI-ELISA remained antibody positive for 11 months or more after initial detection at 10 to 13 days post-inoculation. However, the RAP-1 cELISA did not reliably detect antibody after eight months post-inoculation despite the fact that parasitemia was occasionally detectable by PCR. Furthermore, initial antibody detection by RAP-1 cELISA in low-dose infected animals was delayed approximately nine and a half days compared to the SBP4 MI-ELISA.

Conclusions

These results demonstrate excellent diagnostic sensitivity and specificity of the novel SBP4 MI-ELISA for cattle with acute and long-term carrier infections. It is posited that use of this assay in countries that have B. bovis-endemic herds may be pivotal in preventing the spread of this disease to non-endemic herds.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-017-2016-9) contains supplementary material, which is available to authorized users.

Simulating real-life exposures to uncover possible risks to human health: A proposed consensus for a novel methodological approach

In real life, consumers are exposed to complex mixtures of chemicals via food, water and commercial products consumption. Since risk assessment usually focuses on individual compounds, the current regulatory approach doesn't assess the overall risk of chemicals present in a mixture. This study will evaluate the cumulative toxicity of mixtures of different classes of pesticides and mixtures of different classes of pesticides together with food additives (FAs) and common consumer product chemicals using realistic doses after long-term exposure. Groups of Sprague Dawley (CD-SD) rats (20 males and 20 females) will be treated with mixtures of pesticides or mixtures of pesticides together with FAs and common consumer product chemicals in 0.0, 0.25 × acceptable daily intake (ADI)/tolerable daily intake (TDI), ADI/TDI and 5 × ADI/TDI doses for 104 weeks. All animals will be examined every day for signs of morbidity and mortality. Clinical chemistry hematological parameters, serum hormone levels, biomarkers of oxidative stress, cardiotoxicity, genotoxicity, urinalysis and echocardiographic tests will be assessed periodically at 6 month intervals. At 3-month intervals, ophthalmological examination, test for sensory reactivity to different types of stimuli, together with assessment of learning abilities and memory performance of the adult and ageing animals will be conducted. After 24 months, animals will be necropsied, and internal organs will be histopathologically examined. If the hypothesis of an increased risk or a new hazard not currently identified from cumulative exposure to multiple chemicals was observed, this will provide further information to public authorities and research communities supporting the need of replacing current single-compound risk assessment by a more robust cumulative risk assessment paradigm.

Recognition of Highly Diverse Type-1 and -2 Porcine Reproductive and Respiratory Syndrome Viruses (PRRSVs) by T-Lymphocytes Induced in Pigs after Experimental Infection with a Type-2 PRRSV Strain

Background/Aim

Live attenuated vaccines confer partial protection in pigs before the appearance of neutralizing antibodies, suggesting the contribution of cell-mediated immunity (CMI). However, PRRSV-specific T-lymphocyte responses and protective mechanisms need to be further defined. To this end, the hypothesis was tested that PRRSV-specific T-lymphocytes induced by exposure to type-2 PRRSV can recognize diverse isolates.

Methods

An IFN-gamma ELISpot assay was used to enumerate PRRSV-specific T-lymphocytes from PRRSV_SD23983-infected gilts and piglets born after in utero infection against 12 serologically and genetically distinct type-1 and -2 PRRSV isolates. The IFN-gamma ELISpot assay using synthetic peptides spanning all open reading frames of PRRSV_SD23983 was utilized to localize epitopes recognized by T-lymphocytes. Virus neutralization tests were carried out using the challenge strain (type-2 PRRSV_SD23983) and another strain (type-2 PRRSV_VR2332) with high genetic similarity to evaluate cross-reactivity of neutralizing antibodies in gilts after PRRSV_SD23983 infection.

Results

At 72 days post infection, T-lymphocytes from one of three PRRSV_SD23983-infected gilts recognized all 12 diverse PRRSV isolates, while T-lymphocytes from the other two gilts recognized all but one isolate. Furthermore, five of nine 14-day-old piglets infected in utero with PRRSV_SD23983 had broadly reactive T-lymphocytes, including one piglet that recognized all 12 isolates. Overlapping peptides encompassing all open reading frames of PRRSV_SD23983 were used to identify ≥28 peptides with T-lymphocyte epitopes from 10 viral proteins. This included one peptide from the M protein that was recognized by T-lymphocytes from all three gilts representing two completely mismatched MHC haplotypes. In contrast to the broadly reactive T-lymphocytes, neutralizing antibody responses were specific to the infecting PRRSV_SD23983 isolate.

Conclusion

These results demonstrated that T-lymphocytes recognizing antigenically and genetically diverse isolates were induced by infection with a type 2 PRRSV strain (SD23983). If these reponses have cytotoxic or other protective functions, they may help overcome the suboptimal heterologous protection conferred by conventional vaccines.

Extracellular ATP Induces Calcium Signaling in Odontoblasts

Odontoblasts form dentin at the outermost surface of tooth pulp. An increasing level of evidence in recent years, along with their locational advantage, implicates odontoblasts as a secondary role as sensory or immune cells. Extracellular adenosine triphosphate (ATP) is a well-characterized signaling molecule in the neuronal and immune systems, and its potential involvement in interodontoblast communications was recently demonstrated. In an effort to elaborate the ATP-mediated signaling pathway in odontoblasts, the current study performed single-cell reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescent detection to investigate the expression of ATP receptors related to calcium signal in odontoblasts from incisal teeth of 8- to 10-wk-old rats, and demonstrated an in vitro response to ATP application via calcium imaging experiments. While whole tissue RT-PCR analysis detected P2Y₂, P2Y₄, and all 7 subtypes (P2X₁ to P2X₇) in tooth pulp, single-cell RT-PCR analysis of acutely isolated rat odontoblasts revealed P2Y₂, P2Y₄, P2X₂, P2X₄, P2X₆, and P2X₇ expression in only a subset (23% to 47%) of cells tested, with no evidence for P2X₁, P2X₃, and P2X₅ expression. An increase of intracellular Ca²⁺ concentration in response to 100μM ATP, which was repeated after pretreatment of thapsigargin or under the Ca²⁺-free condition, suggested function of both ionotropic and metabotropic ATP receptors in odontoblasts. The enhancement of ATP-induced calcium response by ivermectin and inhibition by 5-(3-bromophenyl)-1,3-dihydro-2H-benzofuro[3,2-e]-1,4-diazepin-2-one (5-BDBD) confirmed a functional P2X₄ subtype in odontoblasts. Positive calcium response to 2',3'-O-(benzoyl-4-benzoyl)-ATP (BzATP) and negative response to α,β-methylene ATP suggested P2X₂, P2X₄, and P2X₇ as functional subunits in rat odontoblasts. Single-cell RT-PCR analysis of the cells with confirmed calcium response and immunofluorescent detection further corroborated the expression of P2X₄ and P2X₇ in odontoblasts. Overall, this study demonstrated heterogeneous expression of calcium-related ATP receptor subtypes in subsets of individual odontoblasts, suggesting extracellular ATP as a potential signal mediator for odontoblastic functions.

Abstract 4064: The identification of UBR5-ZNF423 recurrent fusion gene in EBV-associated nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a distinct type of head and neck cancer arising from the epithelium of nasopharynx. While the incidence rate of NPC is low in Western countries, it is prevalent in southern China, south-east Asia and northern Africa. Generally, it is believed that multiple factors, including genetic predisposition, environmental carcinogens and Epstein-Barr virus infection, contribute to the tumor initiation and progression of NPC. Similar to other solid tumors in which genetic rearrangements play causal role in the genesis of tumors, our earlier cytogenetic and spectral karyotyping have demonstrated the prevalence of chromosomal translocations in NPC tumors. These evidences suggest that novel fusion gene product arises from chromosomal translocation may contribute to the pathogenesis of the disease.

Using paired-end whole-transcriptome sequencing, we discovered a novel fusion transcript composed of the exon 1 of the ubiquitin protein ligase E3 component n-recognin 5 (UBR5) on 8q22.3 and exon 7-9 of zinc finger protein 423 (ZNF423) on 16q12.1 from the NPC cell line C666-1. Moreover, FISH analysis using break-apart probes validated the UBR5-ZNF423 fusion. Furthermore reverse transcription-PCR (RT-PCR) confirmed the expression of the corresponding fusion transcript. Intriguingly, the fusion transcript was recurrently detected in 12/144 (8.3%) of primary tumors by RT-PCR, which indicates the UBR5-ZNF423 fusion gene may contribute to the genesis of a subset of NPCs.

The growth of C666-1 cells with UBR5-ZNF423 rearrangement is dependent on expression of this fusion protein. Knock-down of UBR5-ZNF423 by RNA interference inhibited the cell proliferation of C666-1 cells. The transforming ability of UBR5-ZNF423 fusion was also confirmed in NIH3T3 mouse fibroblasts by soft agar colony formation assay. Moreover, NIH3T3 cells stably expressing the fusion protein induced tumor formation in nude mice. Furthermore, using an inducible shRNA (Lac operon-driven) targeting the fusion transcript, the growth of C666-1 tumor was suppressed in nude mice. These findings suggest that expression of UBR5-ZNF423 fusion protein contributes to the transformation of a subset of NPCs. Currently, we are working on the functional role(s) of the fusion protein in C666-1 cells. Preliminary results demonstrated that the fusion protein interacts with the Early B-cell Factor 3 (EBF3) and may deregulate EBF3 transcriptional activity. Since EBF3 is a tumor suppressor gene, deregulating EBF3 downstream gene expression by UBR5-ZNF423 may confer to its oncogenic function on NPCs.

In conclusion, we have successfully identified the UBR5-ZNF423 fusion transcript in a subset of NPC tumors. By understanding the molecular mechanisms of this fusion protein on NPCs, novel therapeutic interventions may be implemented on treating a subsets of NPC tumors expressing this oncogenic fusion protein.

Citation Format: Pok Man Hau, Grace Chung, Raymond Lung, Samantha Lun, Chit Chow, Alice Wong, Fei-Fei Liu, George Tsao, Kevin Yip, Ka Fai To, Kwok Wai Lo. The identification of UBR5-ZNF423 recurrent fusion gene in EBV-associated nasopharyngeal carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4064.

Abstract P5-14-04: A phase 2 study evaluating orteronel, an inhibitor of androgen biosynthesis, in patients with androgen receptor (AR)-expressing metastatic breast cancer: Interim analysis

Background: The frequency of AR expression varies in the different breast cancer subtypes with 88%, 59%, and 32% expression reported in ER+, HER2+, and triple negative tumors, respectively. AR expression is associated with resistance to endocrine therapy in ER+ breast cancer. Androgen levels frequently increase following treatment with aromatase inhibitors suggesting a role for androgen synthesis inhibitors in ER+ breast cancer. AR signaling and expression are seen in triple negative breast cancer (TNBC), and a distinct AR TNBC subtype can be identified by gene expression profiling. AR expression in TNBC offers a potential therapeutic target. Preclinical and clinical studies demonstrated anti-androgen agent activity in breast cancer cell lines; preliminary clinical data suggests activity in TNBC. Orteronel is a novel, oral, selective, nonsteroidal inhibitor of 17, 20-lyase, a key enzyme in androgen biosynthesis that is being evaluated as endocrine therapy in various hormone-sensitive cancers. In this phase 2 study we are evaluating single agent orteronel in AR+ MBC.

Methods: Pts with AR expressing MBC (≥10% staining by central immunohistochemistry) were eligible. Pts were grouped into 2 cohorts for analysis: Cohort 1-TNBC and Cohort 2-ER+ (HER2 could be +/- in this cohort). Pts must have been previously treated with standard therapy for MBC (1-3 chemotherapy regimens for TNBC, 1-3 hormonal therapies + 1 chemotherapy for ER+ patients, ≥2 HER2-targeted regimens for HER2+ patients). A 6 pt lead-in for safety and tolerability of orteronel in AR+ female MBC pts was followed by open enrollment to either cohort. All pts received 300 mg orteronel PO BID over a 4 week cycle and underwent response assessment every 2 cycles. Treatment was continued until disease progression or unacceptable toxicity. The hypothesized response rate for Cohort 1 was 10% and 13% for Cohort 2. We present the results of a protocol-specified interim analysis of the ER+ MBC pts (Cohort 2).

Results: From 3/2014 to 4/2015, a total of 29 pts were enrolled on cohort 2. Median age was 65 years (range, 39-79); 90% ECOG ≤1; 90% HER2-/10% HER2+; median of 7 prior therapies (range 3-11). 93% had prior chemotherapy. Pts received a median of 2 cycles of orteronel treatment (range 1-4) and 3 pts (10%) are still on treatment. Of the 26 pts (90%) pts that have discontinued, 19 (66%) discontinued due to disease progression, 4 (14%) due to pt decision, 2 (7%) due to adverse event (AE), and 1 (3%) due to non-compliance. The most common treatment-related G 3/4 AEs were increased lipase [3 pts (10%)] and hypertension [2 pts (7%)]. There were no treatment-related SAEs or deaths on study. Three pts (10%) had stable disease as their best response. Further response evaluation is underway.

Conclusions: Orteronel monotherapy was well tolerated but appears to have limited single-agent activity in this heavily pre-treated ER+ MBC pt population. The full results from this interim analysis will be presented.

Citation Format: Yardley DA, Peacock N, Young RR, Silber A, Chung G, Webb CD, Jones SF, Shastry M, Midha R, DeBusk LM, Hainsworth JD, Burris HA. A phase 2 study evaluating orteronel, an inhibitor of androgen biosynthesis, in patients with androgen receptor (AR)-expressing metastatic breast cancer: Interim analysis. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-14-04.

Enhanced sensitivity of an antibody competitive blocking enzyme-linked immunosorbent assay using Equine arteritis virus purified by anion-exchange membrane chromatography

In an effort to improve a competitive blocking enzyme-linked immunosorbent assay (cELISA) for antibody detection to Equine arteritis virus (EAV), antigen purified by anion-exchange membrane chromatography capsule (AEC) was evaluated. Virus purification by the AEC method was rapid and easily scalable. A comparison was made between virus purified by the AEC method with that obtained by differential centrifugation based on the following: 1) the relative purity and quality of EAV glycoprotein 5 (GP5) containing the epitope defined by monoclonal antibody 17B7, and 2) the relative sensitivity of a commercial antibody cELISA with the only change being the 2 purified antigens. On evaluation by Western blot using GP5-specific monoclonal antibody 17B7, the AEC-purified EAV contained 86% GP5 monomer whereas the differentially centrifuged EAV contained <29% of the monomer. Improvement of analytical sensitivity without sacrifice of analytical specificity was clearly evident when cELISAs prepared with EAV antigen by each purification method were evaluated using 7 sensitivity and specificity check sets. Furthermore, the AEC-purified EAV-based cELISA had 30-40% higher agreement with the virus neutralization (VN) test than the cELISA prepared with differentially centrifuged EAV based on testing 40 borderline EAV-seropositive samples as defined by the VN test. In addition, the AEC-purified cELISA had highly significant (P = 0.001) robustness indicated by intra-laboratory repeatability and interlaboratory reproducibility when evaluated with the sensitivity check sets. Thus, use of AEC-purified EAV in the cELISA should lead to closer harmonization of the cELISA with the World Organization for Animal Health-prescribed VN test.

Discovery of N-(4-(3-(2-aminopyrimidin-4-yl)pyridin-2-yloxy)phenyl)-4-(4-methylthiophen-2-yl)phthalazin-1-amine (AMG 900), a highly selective, orally bioavailable inhibitor of aurora kinases with activity against multidrug-resistant cancer cell lines

Efforts to improve upon the physical properties and metabolic stability of Aurora kinase inhibitor 14a revealed that potency against multidrug-resistant cell lines was compromised by increased polarity. Despite its high in vitro metabolic intrinsic clearance, 23r (AMG 900) showed acceptable pharmacokinetic properties and robust pharmacodynamic activity. Projecting from in vitro data to in vivo target coverage was not practical due to disjunctions between enzyme and cell data, complex and apparently contradictory indicators of binding kinetics, and unmeasurable free fraction in plasma. In contrast, it was straightforward to relate pharmacokinetics to pharmacodynamics and efficacy by following the time above a threshold concentration. On the basis of its oral route of administration, a selectivity profile that favors Aurora-driven pharmacology and its activity against multidrug-resistant cell lines, 23r was identified as a potential best-in-class Aurora kinase inhibitor. In phase 1 dose expansion studies with G-CSF support, 23r has shown promising single agent activity.

Desipramine inhibits salivary Ca(2+) signaling and aquaporin translocation

OBJECTIVE

Desipramine is a tricyclic antidepressant with a negative side effect of dry mouth. The Na(+) /H(+) exchanger was suggested to be a target of desipramine in salivary gland cells. However, it is unclear whether desipramine has other targets in the salivary secretion pathway. Here, we studied the effect of desipramine on salivary Ca(2+) signaling.

MATERIALS AND METHODS

Cytosolic free Ca(2+) concentration ([Ca(2+) ]i ) was determined with the fluorescent Ca(2+) indicator fura-2/AM. Aquaporin translocation was analyzed by Western blotting and immunocytochemistry of confocal microscopy.

RESULTS

Desipramine inhibited the carbachol- and histamine-mediated increase in cytosolic Ca(2+) ([Ca(2+) ]i ) in a concentration-dependent manner. However, desipramine did not affect increases in [Ca(2+) ]i mediated by extracellular ATP, sphingosine-1-phosphate, or thapsigargin. The adrenergic receptor blockers prazosin and propranolol did not reverse the desipramine-mediated inhibition of carbachol- and histamine-induced increases in [Ca(2+) ]i . We also found that desipramine inhibits the increase in membrane aquaporin-5 level triggered by carbachol and histamine treatments.

CONCLUSIONS

These results imply that desipramine blocks muscarinic and histamine receptor-mediated Ca(2+) signaling and the subsequent translocation of aquaporin-5 in human salivary gland cells, suggesting a novel mechanism for the xerogenic effects of desipramine.

AMG 900, a potent inhibitor of aurora kinases causes pharmacodynamic changes in p-Histone H3 immunoreactivity in human tumor xenografts and proliferating mouse tissues

BACKGROUND

The Aurora family of serine-threonine kinases are essential regulators of cell division in mammalian cells. Aurora-A and -B expression and kinase activity is elevated in a variety of human cancers and is associated with high proliferation rates and poor prognosis. AMG 900 is a highly potent and selective pan-aurora kinase inhibitor that has entered clinical evaluation in adult patients with advanced cancers. In mice, oral administration of AMG 900 blocks the phosphorylation of histone H3 on serine-10 (p-Histone H3), a proximal substrate of aurora-B and inhibits the growth of multiple human tumor xenografts, including multidrug-resistant models.

METHODS

In order to establish a preclinical pharmacokinetic-pharmacodynamic (PK-PD) relationship for AMG 900 that could be translated to the clinic, we used flow cytometry and laser scanning cytometry detection platforms to assess the effects on p-Histone H3 inhibition in terms of sensitivity, precision, and specificity, in human tumor xenografts in conjunction with mouse skin and bone marrow tissues. Mice with established COLO 205 tumors were administered AMG 900 at 3.75, 7.5, and 15 mg/kg and assessed after 3 hours.

RESULTS

Significant suppression of p-Histone H3 in mouse skin was only observed at 15 mg/kg (p <0.0001), whereas in mouse bone marrow and in tumor a dose-dependent inhibition was achieved at all three doses (p ≤ 0.00015). These studies demonstrate that AMG 900 inhibits p-Histone H3 in tumors and surrogate tissues (although tissues such as skin may be less sensitive for assessing PD effects). To further extend our work, we evaluated the feasibility of measuring p-Histone H3 using fine-needle aspirate (FNA) tumor xenograft biopsies. Treatment with AMG 900 significantly inhibited p-Histone H3 (>99% inhibition, p <0.0001) in COLO 205 tumors. Lastly, we illustrate this LSC-based approach can detect p-Histone H3 positive cells using mock FNAs from primary human breast tumor tissues.

CONCLUSION

Phosphorylation of histone H3 is a useful biomarker to determine the pharmacodynamics (PD) activity of AMG 900. FNA biopsies may be a viable approach for assessing AMG 900 PD effects in the clinic.

Activation of transient receptor potential ankyrin 1 by eugenol

Eugenol is a bioactive plant extract used as an analgesic agent in dentistry. The structural similarity of eugenol to cinnamaldehyde, an active ligand for transient receptor potential ankyrin 1 (TRPA1), suggests that eugenol might produce its effect via TRPA1, in addition to TRPV1 as we reported previously. In this study, we investigated the effect of eugenol on TRPA1, by fura-2-based calcium imaging and patch clamp recording in trigeminal ganglion neurons and in a heterologous expression system. As the result, eugenol induced robust calcium responses in rat trigeminal ganglion neurons that responded to a specific TRPA1 agonist, allyl isothiocyanate (AITC), and not to capsaicin. Capsazepine, a TRPV1 antagonist failed to inhibit eugenol-induced calcium responses in AITC-responding neurons. In addition, eugenol response was observed in trigeminal ganglion neurons from TRPV1 knockout mice and human embryonic kidney 293 cell lines that express human TRPA1, which was inhibited by TRPA1-specific antagonist HC-030031. Eugenol-evoked TRPA1 single channel activity and eugenol-induced TRPA1 currents were dose-dependent with EC50 of 261.5μM. In summary, these results demonstrate that the activation of TRPA1 might account for another molecular mechanism underlying the pharmacological action of eugenol.

Abstract P3-14-02: Patterns of the use of primary systemic therapy in the United States

Background: Primary systemic therapy (PST) is an accepted alternative to adjuvant systemic therapy of breast cancer. It provides equivalent survival, increased breast conservation rates, and prognostic information.

Methods: This analysis assesses patterns of PST use based on information collected by the National Cancer Database (NCDB), a joint project of the American College of Surgeons and the American Cancer Society which captures data on over 70% of all diagnosed breast cancer patients in the U.S. Using the b-participant use file of the NCDB, we evaluated regional, patient, and tumor factors associated with PST use.

Results: The NCDB captured 621,319 patients treated with PST from 2006 to 2010. Of these, 7.4% received systemic therapy pre-operatively, and 3.6% in both the pre- and post-operative settings. Factors correlating with timing of therapy are shown in the table. PST use increased steadily from 7.0% to 7.8% (p&lt;0.001) from 2006 to 2010. PST was significantly more frequently used in younger, African-American, Hispanic, low-income, uninsured patients with larger, node positive tumors, living in large metropolitan areas in the West and treated in academic centers. These factors remained significantly and independently associated with PST on multivariate analysis.

 UnivariateMultivariateFactorPre-opPost-opBothp-valuep-valueYear of Diagnosis   &lt;0.001&lt;0.00120067.0%90.0%3.0%  20077.1%89.5%3.4%  20087.2%89.2%3.6%  20097.6%88.6%3.8%  20107.8%87.7%4.5%  Region   &lt;0.001&lt;0.001Northeast5.7%90.9%3.4%  Atlantic6.7%90.4%2.9%  Southeast8.0%88.2%3.8%  Great Lakes6.5%90.1%3.4%  South7.7%88.4%3.9%  Midwest5.2%90.2%4.6%  West11.4%84.2%4.4%  Mountain8.8%88.7%2.5%  Pacific7.7%88.3%4.0%  Community type (pop):   &lt;0.001&lt;0.001Metro (&gt;1M)7.9%88.3%3.8%  Metro (250K-1M)7.1%89.5%3.4%  Metro (&lt;250K)6.3%90.5%3.2%  Urban, adjacent to a metro area (20K+)6.5%90.0%3.5%  Urban, not adjacent to metro (20K+)6.3%90.5%3.2%  Urban, adjacent to metro (2500-19,999)6.7%89.4%4.0%  Urban, not adjacent to metro (2500-19,999)6.0%90.6%3.4%  Rural/urban pop, adjacent to metro (&lt;2500)6.0%90.3%3.8%  Rural/urban pop, not adjacent to metro (&lt;2500)5.7%90.5%3.8%  Facility type:   &lt;0.001&lt;0.001Community program6.4%90.5%3.1%  Comprehensive community program7.1%89.5%3.5%  Academic/research8.4%87.4%4.2%  Other6.4%90.0%3.6%  Age:   &lt;0.001&lt;0.001&lt;609.4%85.8%4.8%  ≥604.9%92.9%2.3%  Race:   &lt;0.001&lt;0.001Caucasian6.7%89.3%3.5%  African-American11.8%83.3%4.9%  Other8.4%87.5%4.1%  Ethnicity:   &lt;0.001&lt;0.001Non-Hispanic7.2%89.3%3.6%  Hispanic11.2%83.3%5.4%  Median household income:   &lt;0.0010.023&lt;$30K9.0%86.8%4.2%  $30K-$34,9997.7%88.6%3.7%  $35K-$45,9997.2%89.1%3.7%  $46K+6.9%89.6%3.4%  Insurance:   &lt;0.001&lt;0.001Uninsured15.3%78.1%6.6%  Private7.8%88.3%3.9%  Medicaid13.7%79.2%7.2%  Medicare4.8%93.0%2.2%  Military8.2%87.5%4.4%  Clinical T stage:   &lt;0.001&lt;0.001T12.4%96.4%1.2%  T213.6%79.5%6.9%  T3-T435.9%45.3%18.8%  Clinical N stage:   &lt;0.001&lt;0.001N04.8%92.9%2.3%  N1-326.0%60.3%13.7%  pop: population; multivariate OR and 95% CI not shown

Conclusion: PST appears to be underutilized, received by only 7.8% of all patients, 36% of T3-T4 tumors, and 26.0% of clinically node positive patients. However, its rate of use has increased over the past years. There is also significant regional variation in the use of PST, independent of patient and tumor factors.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-14-02.

Abstract P6-11-03: Follow up of breast cancer patients who underwent gamma knife radiosurgery for a diagnosis of brain metastases: A single institutional experience

Background: Breast cancer (BC) is the second most common cause of brain metastases in the United States. We performed a retrospective analysis of BC patients (pts) in the Yale Gamma Knife Radiosurgery (GKRS) database treated for brain metastases (mets) to report overall survival (OS) from time of GKRS, and to identify factors that predict improved survival outcomes.

Methods: We performed retrospective review of the Yale database of BC pts treated with standard GKRS technique for brain mets from 2000 to May 2013. Treatment doses typically ranged from 16 to 24 Gy prescribed to the 40-85% isodose surfaces. Overall survival (OS) for each patient was calculated from the date of first GKRS treatment of brain metastases. Variables included age, Karnofsky Performance Status (KPS), pre/post whole-brain radiation treatment (WBRT) and/or surgical resection, and # of brain mets treated (1-4 vs ≥5).

Results: A total of 80 BC pts were identified, with a mean age of 56.2 yrs; KPS 40-60 in 8pts (10%), 70-80 in 13 (16%), 90-100 in 41 (51%), unknown in 18 (23%); ER+ in 38 (48%), ER- in 38 (48%), unknown in 4 (5%); HER2 + in 38 (48%), HER2- in 33 (41%), indeterminate in 3 (4%) and unknown in 6 (8%). BC subtypes are Luminal A (ER+/HER2-) in 16 (20%), Luminal B (ER+/HER2+) in 19 (24%), HER-2(ER-/HER2+) in 17 (21%), Basal (ER-/HER2-) in 17 (21%), unknown in 11 (14%). Number of brain mets at time of first GKRS ≥5 in 32 (40%); prior WBRT in 30 (38%); WBRT post GKRS in 9 (11%); surgical resection for brain mets in 13 (16%) prior to GKRS and post GKRS in 9 (11%); 16% had ≥3 GKRS. Median time from primary BC dx to brain mets is 62.8 months (m) (range 46.2-81.6); with no significant difference among subtypes. Median OS from GKRS is 13.1 m (7.6-21.9); median OS from brain mets is 18.8 m (11.7-23.9). On univariate analysis, factors associated with significant improved OS from time of GKRS included HER-2 subtype (p = 0.005), KPS 90-100 (p = 0.008), good control of systemic disease (p = 0.017), pre (p = 0.041) and post GKRS surgical resection (p = 0.02). Age, pre or post WBRT, # of brain mets (1-4 vs. 5) were not significant predictors of OS from time of GKRS. In a multivariate Cox analysis (46 cases), HER-2 subtype remained a significant predictor of improved OS from time of GKRS; (HR) 0.26, 95%CI 0.08 to 0.8, p-value = 0.02. There was a trend in favor of surgical resection of brain mets pre GKRS (HR 0.14, 95% CI 0.02 to 1.15, p-value = 0.067

Conclusion: GKRS offers good local control for BC pts with brain mets, and is a reasonable option for pts with ≥5 brain mets. Our results show no associated survival benefit for administration of WBRT pre/post GKRS. HER-2 subtype is a significant predictor of improved survival in BC pts undergoing GKRS for brain mets.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-11-03.

Abstract P5-13-05: Richer and wiser: Factors correlated with chemoprevention use in the United States

Introduction: Tamoxifen and raloxifene have been shown to reduce the risk of breast cancer by up to 50%, yet the uptake of these agents remains poor. We sought to determine factors associated with chemoprevention uptake in a nationally representative sample.

Methods: The National Health Interview Survey (NHIS) is a population-based survey conducted annually by the CDC and is designed to be representative of the non-institutionalized civilian population in the United States. We utilized data from the 2010 NHIS cancer supplement to determine factors associated with chemoprevention uptake in women ≥ 35 years of age. Statistical analyses were conducted using SUDAAN software.

Results: In 2010, 10,959 women ≥ 35 years of age were surveyed, representing 83,377,082 people in the population. Of these, 0.21% reported taking chemoprevention, using either tamoxifen or raloxifene. On bivariate analyses, factors correlating with chemoprevention uptake included age, race/ethnicity, education, insurance, income and geographic region (see Table). Interestingly, MRI use, family history of premenopausal breast cancer in first degree relatives, and personal risk perception were not associated with chemoprevention use. On multivariate analysis, education and income remained independent predictors of chemoprevention use.

Conclusion: Approximately 0.2% of women take chemoprevention. It is concerning that sociodemographic factors of education and income are independent predictors of the use of chemopreventive agents for breast cancer, while risk perception and family history do not seem to correlate with uptake rates. These findings are a call to action for improved education and counseling of those who are at greatest risk, and highlight potential disparities in access to appropriate chemoprevention across all sociodemographic groups.

Bivariate and Multivariate Analyses of Factors Correlated with Chemoprevention UptakeFactorBivariate AnalysisMultivariate Analysis Chemoprevention (%)No Chemoprevention (%)p-valueOR (95% CI)p-valueAge  0.0481 0.1087&lt; 40 yr3.2211.93 1.00 40-49 yr5.8726.11 0.78 (0.05-12.44) 50-59 yr11.7024.88 1.44 (0.10-21.43) 60-69 yr23.8218.54 3.15 (0.32-31.41) 70-79 yr44.4110.77 8.62 (0.78-94.75) 80+ yr10.997.77 1.53 (0.10-23.66) Race/ethnicity  0.0006 0.8372Hispanic3.9011.06 00.81 (0.11-5.85) White96.1071.63 1.00 Black011.80 - Asian04.61 - Other00.89 - Education  0.0371 &lt;0.0001&lt; Grade 127.1214.15 1.00 High School25.8627.73 1.86 (0.35-9.75) Some college/Assoc21.4229.97 1.85 (0.36-9.45) Bachelors15.5917.49 1.44 (0.13-16.35) Masters11.708.37 3.23 (0.41-25.14) Prof/Doctorate18.302.28 25.22 (4.30-147.87) Insurance  0.0002 0.0686Not covered012.44 - Medicare72.6129.38 1.00 Medicaid3.224.50 2.38 (0.22-26.15) Military01.74 - Private24.1751.94 0.28 (0.06-1.26) Income  0.0005 0.0306&lt;$35K32.3934.53 1.00 $35K-$74,99926.1131.53 0.97 (0.21-4.42) $75K-$99,999012.08 - $100K+41.6021.86 3.78 (0.94-15.22) Region  0.0441 0.1649Northeast27.9318.62 1.00 Midwest31.6022.88 0.92 (0.32-2.64) South34.4935.66 0.65 (0.21-2.04) West5.9822.84 0.16 (0.03-0.86) Oophorectomy40.1115.160.08132.17 (0.77-6.09)0.1404MRI use2.315.170.2597  Family History2.315.130.2601  Risk Perception  0.1451  High41.5212.50   Average25.8947.49   Low32.5940.01   

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-13-05.

Pain fiber anesthetic reduces brainstem Fos after tooth extraction

We recently demonstrated that pain-sensing neurons in the trigeminal system can be selectively anesthetized by co-application of QX-314 with the TRPV1 receptor agonist, capsaicin (QX cocktail). Here we examined whether this new anesthetic strategy can block the neuronal changes in the brainstem following molar tooth extraction in the rat. Adult male Sprague-Dawley rats received infiltration injection of anesthetic 10 min prior to lower molar tooth extraction. Neuronal activation was determined by immunohistochemistry for the proto-oncogene protein c-Fos in transverse sections of the trigeminal subnucleus caudalis (Sp5C). After tooth extraction, c-Fos-like immunoreactivity (Fos-LI) detected in the dorsomedial region of bilateral Sp5C was highest at 2 hrs (p < .01 vs. naïve ipsilateral) and declined to pre-injury levels by 8 hrs. Pre-administration of the QX cocktail significantly reduced to sham levels Fos-LI examined 2 hrs after tooth extraction; reduced Fos-LI was also observed with the conventional local anesthetic lidocaine. Pulpal anesthesia by infiltration injection was confirmed by inhibition of the jaw-opening reflex in response to electrical tooth pulp stimulation. Our results suggest that the QX cocktail anesthetic is effective in reducing neuronal activation following tooth extraction. Thus, a selective pain fiber 'nociceptive anesthetic' strategy may provide an effective local anesthetic option for dental patients in the clinic.

AMG 900, a small-molecule inhibitor of aurora kinases, potentiates the activity of microtubule-targeting agents in human metastatic breast cancer models

Breast cancer is the most prevalent malignancy affecting women and ranks second in cancer-related deaths, in which death occurs primarily from metastatic disease. Triple-negative breast cancer (TNBC) is a more aggressive and metastatic subtype of breast cancer that is initially responsive to treatment of microtubule-targeting agents (MTA) such as taxanes. Recently, we reported the characterization of AMG 900, an orally bioavailable, potent, and highly selective pan-Aurora kinase inhibitor that is active in multidrug-resistant cell lines. In this report, we investigate the activity of AMG 900 alone and in combination with two distinct classes of MTAs (taxanes and epothilones) in multidrug-resistant TNBC cell lines and xenografts. In TNBC cells, AMG 900 inhibited phosphorylation of histone H3 on Ser(10), a proximal substrate of Aurora-B, and induced polyploidy and apoptosis. Furthermore, AMG 900 potentiated the antiproliferative effects of paclitaxel and ixabepilone at low nanomolar concentrations. In mice, AMG 900 significantly inhibited the growth of MDA-MB-231 (F(11); parental), MDA-MB-231 (F(11)) PTX-r (paclitaxel-resistant variant), and DU4475 xenografts. The combination of AMG 900 with docetaxel enhanced tumor inhibition in MDA-MB-231 (F(11)) xenografts compared with either monotherapy. Notably, combining AMG 900 with ixabepilone resulted in regressions of MDA-MB-231 (F(11)) PTX-r xenografts, in which more than 50% of the tumors failed to regrow 75 days after the cessation of drug treatment. These findings suggest that AMG 900, alone and in combination with MTAs, may be an effective intervention strategy for the treatment of metastatic breast cancer and provide potential therapeutic options for patients with multidrug-resistant tumors.

Cellular and molecular mechanisms of dental nociception

Due, in part, to the unique structure of the tooth, dental pain is initiated via distinct mechanisms. Here we review recent advances in our understanding of inflammatory tooth pain and discuss 3 hypotheses proposed to explain dentinal hypersensitivity: The first hypothesis, supported by functional expression of temperature-sensitive transient receptor potential channels, emphasizes the direct transduction of noxious temperatures by dental primary afferent neurons. The second hypothesis, known as hydrodynamic theory, attributes dental pain to fluid movement within dentinal tubules, and we discuss several candidate cellular mechanical transducers for the detection of fluid movement. The third hypothesis focuses on the potential sensory function of odontoblasts in the detection of thermal or mechanical stimuli, and we discuss the accumulating evidence that supports their excitability. We also briefly update on a novel strategy for local nociceptive anesthesia via nociceptive transducer molecules in dental primary afferents with the potential to specifically silence pain fibers during dental treatment. Further understanding of the molecular mechanisms of dental pain would greatly enhance the development of therapeutics that target dental pain.

Attention to inpatients' religious and spiritual concerns: predictors and association with patient satisfaction

BACKGROUND

Little is known about how often patients desire and experience discussions with hospital personnel regarding R/S (religion and spirituality) or what effects such discussions have on patient satisfaction. OBJECTIVE, DESIGN AND PARTICIPANTS: We examined data from the University of Chicago Hospitalist Study, which gathers sociodemographic and clinical information from all consenting general internal medicine patients at the University of Chicago Medical Center.

MAIN MEASURES

Primary outcomes were whether or not patients desired to have their religious or spiritual concerns addressed while hospitalized, whether or not anyone talked to them about religious and spiritual issues, and which member of the health care team spoke with them about these issues. Primary predictors were patients' ratings of their religious attendance, their efforts to carry their religious beliefs over into other dealings in life, and their spirituality.

KEY RESULTS

Forty-one percent of inpatients desired a discussion of R/S concerns while hospitalized, but only half of those reported having such a discussion. Overall, 32% of inpatients reported having a discussion of their R/S concerns. Religious patients and those experiencing more severe pain were more likely both to desire and to have discussions of spiritual concerns. Patients who had discussions of R/S concerns were more likely to rate their care at the highest level on four different measures of patient satisfaction, regardless of whether or not they said they had desired such a discussion (odds ratios 1.4-2.2, 95% confidence intervals 1.1-3.0).

CONCLUSIONS

These data suggest that many more inpatients desire conversations about R/S than have them. Health care professionals might improve patients' overall experience with being hospitalized and patient satisfaction by addressing this unmet patient need.

Abstract 3556: Antitumor activity of AMG 900, an orally available small molecule inhibitor of aurora kinases, alone and in combination with tubulin-targeting agents in human metastatic breast cancer

Background: Breast cancer is a heterogeneous disease that can be classified into distinct subtypes. The breast cancer subtype that lacks expression of hormone receptors (ER and PR) is characterized by its aggressive and metastatic nature. Tubulin-targeting agents are among the most active agents for the treatment of metastatic breast cancer (MBC). However, treatment of MBC frequently fails because of de novo or acquired resistance to taxanes. Consequently, there is an urgent need for novel therapeutics and combination strategies to effectively treat multidrug-resistant MBC. Recently, we reported the development of AMG 900, a novel ATP competitive small molecule inhibitor that is potent and selective for aurora-A, -B, and -C kinases. AMG 900 inhibits the proliferation of tumor cell lines and growth of multiple human xenografts, including taxane-resistant models. AMG 900 is currently in early clinical testing in advanced cancers.

Objective: To evaluate the effectiveness of AMG 900 alone and in combination with two different classes of tubulin-targeting agents (taxanes and epothilones) in human MDA-MB-231 (parental and taxane-resistant subline) MBC cell lines and xenografts.

Results: The MDA-MB-231 parental cell line is tumorigenic and metastatic in vivo. To establish the taxane-resistant cell line, MDA-MB-231-PTX-r, MDA-MB-231 parental cells were adapted to grow in the presence of increasing concentrations of paclitaxel. In vitro, AMG 900 induced polyploidy and inhibited colony growth of both MDA-MB-231 and MDA-MB-231-PTX-r cell lines. In combination, AMG 900 enhanced the effects of both paclitaxel and ixabepilone in a cell growth assay using MDA-MB-231 and MDA-MB-231-PTX-r cell lines, respectively. In tumor-bearing mice, AMG 900 blocked the phosphorylation of histone H3 and significantly inhibited the growth of both MDA-MB-231 and MDA-MB-231-PTX-r xenografts (&gt;70% inhibition; p &lt; 0.0002). To examine the effects of AMG 900 in combination with tubulin-targeting agents, mice were administered either docetaxel or ixabepilone (day 1) followed by AMG 900 (day 2 and 3). AMG 900 plus docetaxel resulted in enhanced efficacy in the MDA-MB-231 xenografts compared to either single agent (p &lt; 0.0006). Notably, AMG 900 plus ixabepilone resulted in tumor regressions in the MDA-MB-231-PTX-r xenografts compared to either single agent (p &lt; 0.0001). Histological analysis of the MDA-MB-231-PTX-r tumors revealed a pronounced increase in multinucleated cells after combined treatment with AMG 900 and ixabepilone compared to either single agent.

Conclusion: AMG 900, alone or in combination with tubulin-targeting agents such as ixabepilone, has the potential to treat multidrug resistant metastatic breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3556. doi:10.1158/1538-7445.AM2011-3556

Characterization of Dental Nociceptive Neurons

Selective blockade of nociceptive neurons can be achieved by the delivery of permanently charged sodium channel blockers through the pores of nociceptive ion channels. To assess the feasibility of this application in the dental area, we investigated the electrophysiological and neurochemical characteristics of nociceptive dental primary afferent (DPA) neurons. DPA neurons were identified within trigeminal ganglia labeling with a retrograde fluorescent dye applied to the upper molars of adult rats. Electrophysiological studies revealed that the majority of dental primary afferent neurons showed characteristics of nociceptive neurons, such as sensitivity to capsaicin and the presence of a hump in action potential. Immunohistochemical analysis revealed a large proportion of DPA neurons to be IB4-positive and to express TRPV1 and P2X3. Single-cell RT-PCR revealed mRNA expression of various nociceptive channels, including the temperature-sensitive TRPV1, TRPA1, TRPM8 channels, the extracellular ATP receptor channels P2X2 and P2X3, as well as the nociceptor-specific sodium channel, NaV1.8. In conclusion, DPA neurons have the electrophysiological characteristics of nociceptors and express several nociceptor-specific ion channels. Analysis of these data may assist in the search for a new route of entry for the delivery of membrane-impermeant local anesthetics. Abbreviations: AP, action potential; DiI, 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate; DPA, dental primary afferent; FITC, fluorescein 5(6)-isothiocyanate; IB4, isolectin-B4; RT-PCR, reverse-transcription polymerase chain-reaction; TRP, transient receptor potential.

Abstract P3-14-17: Trastuzumab (H) and Rapamycin (R) for Treatment of HER-2 Overexpressing Metastatic Breast Cancer (BC) with Prior Disease Progression on H Based Therapy: Safety and Pharmacodynamic (PD) Results

Background: Preclinical data shows upregulation of the PI3K/AKT pathway and synergistic cytotoxicty between H+R in sensitive and resistant HER-2 overexpressing BC cell lines.

Methods: We designed a phase II clinical trial with an early stopping rule for excess toxicity in the first 4 wks of H+R therapy, defined as ≥3 cases of drug related grade 3 or 4 toxicity observed in the first 9 pts enrolled on trial. We report safety and PD results in 11 pts treated with oral R 6 mg daily + standard dosesand schedule of H. LVEF by ECHO or MUGA was assessed at baseline and every 3 months thereafter; treatment was held for LVEF drop below normal limits or ≥20 percentage points. Pre and post therapy tumor samples were collected when feasible. Circulating tumor (CTC) and endothelial (CEC) cells were collected and analyzed using the Veridex Cell Search System at baseline, wks 1, 2 and 4 and with every restaging.

Results: 11 pts with median age 56 y (range 38-70) treated with H+R were evaluable for safety. Median # cycles was 3 (range 1+ to 12). Non-hematologic grade 3 toxicities in first 4 wks occurred in 3 of the first 9 pts: 1 pt had syncope associated with leucopenia/neutropenia and urinary infection; 1pt had mucositis which responded to dose reduction; 1 pt with known diabetes had grade 3 hyperglycemia, however, this was non-fasting. One pt had grade 3 leucopenia/neutropenia which responded to dose reduction. Grade 3 toxicities for 11 pts in all cycles were as follows: leucopenia/neutropenia (2 pts), non-fasting hyperglycemia (2 pts), syncope (1 pt), hypokalemia (1pt), hyponatremia (1 pt), mucositis (1 pt), rash (2 pts), nail changes (1 pt), thrombosis (1 pt). Infection (urine in 1 pt, skin in 1 pt), anemia (1pt), and elevated PTT (1 pt). One grade 4 non-fasting hyperglycemia occurred in a diabetic pt. LVEF dropped below normal limits and recovered subsequently in 2 pts. Nine pts had baseline and at least one subsequent evaluation for radiographic response by RECIST. Best response was unconfirmed partial response (PR) in 1 pt (8 cycles), stable disease (SD) in 5 pts (12, 6+,6, 3, and 2 cycles) and progression (PD) in 3pts. We combined analysis of AKT pathway markers from 12 baseline and 9 post therapy tissue samples collected on this trial and a phase I study of R +chemotherapy. There were high correlations between baseline AKT pathway markers (mTOR, PTEN, Akt, pAkt, S6K1 and pS6K1; (Spearman's rho-0.401-0.907). This correlation was lost in post therapy samples. Higher mean mTOR levels were seen in non-responders (PD) vs. responders (SD/PR) [p value=0.04]. Eight pts had CTC and CEC results, and were evaluable for response. Baseline CTC levels of &gt;5 cells/7.5 ml were seen in 2/2 pts with PD and 0/6 pts with SD/PR. There was no significant difference in CEC levels between responders and non-responders. Conclusion: R 6 mg daily appears to be well tolerated when combined with standard doses of H. PR in 1 pt and SD for ≥6 months was observed in 2 pts with prior progression on H based therapy. Baseline elevated mTOR level correlates with poor response to R based combinations. Post therapy change in marker expression suggests biologic effect of R.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-14-17.

Preclinical evaluation of AMG 900, a novel potent and highly selective pan-aurora kinase inhibitor with activity in taxane-resistant tumor cell lines

In mammalian cells, the aurora kinases (aurora-A, -B, and -C) play essential roles in regulating cell division. The expression of aurora-A and -B is elevated in a variety of human cancers and is associated with high proliferation rates and poor prognosis, making them attractive targets for anticancer therapy. AMG 900 is an orally bioavailable, potent, and highly selective pan-aurora kinase inhibitor that is active in taxane-resistant tumor cell lines. In tumor cells, AMG 900 inhibited autophosphorylation of aurora-A and -B as well as phosphorylation of histone H3 on Ser(10), a proximal substrate of aurora-B. The predominant cellular response of tumor cells to AMG 900 treatment was aborted cell division without a prolonged mitotic arrest, which ultimately resulted in cell death. AMG 900 inhibited the proliferation of 26 tumor cell lines, including cell lines resistant to the antimitotic drug paclitaxel and to other aurora kinase inhibitors (AZD1152, MK-0457, and PHA-739358), at low nanomolar concentrations. Furthermore, AMG 900 was active in an AZD1152-resistant HCT116 variant cell line that harbors an aurora-B mutation (W221L). Oral administration of AMG 900 blocked the phosphorylation of histone H3 in a dose-dependent manner and significantly inhibited the growth of HCT116 tumor xenografts. Importantly, AMG 900 was broadly active in multiple xenograft models, including 3 multidrug-resistant xenograft models, representing 5 tumor types. AMG 900 has entered clinical evaluation in adult patients with advanced cancers and has the potential to treat tumors refractory to anticancer drugs such as the taxanes.