A Distinct Metabolite Signature in Military Personnel Exposed to Repetitive Low-Level Blasts

Military Breachers and Range Staff (MBRS) are subjected to repeated sub-concussive blasts, and they often report symptoms that are consistent with a mild traumatic brain injury (mTBI). Biomarkers of blast injury would potentially aid blast injury diagnosis, surveillance and avoidance. Our objective was to identify plasma metabolite biomarkers in military personnel that were exposed to repeated low-level or sub-concussive blast overpressure. A total of 37 military members were enrolled (18 MBRS and 19 controls), with MBRS having participated in 8–20 breaching courses per year, with a maximum exposure of 6 blasts per day. The two cohorts were similar except that the number of blast exposures were significantly higher in the MBRS, and the MBRS cohort suffered significantly more post-concussive symptoms and poorer health on assessment. Metabolomics profiling demonstrated significant differences between groups with 74% MBRS classification accuracy (CA). Feature reduction identified 6 metabolites that resulted in a MBRS CA of 98%, and included acetic acid (23.7%), formate (22.6%), creatine (14.8%), acetone (14.2%), methanol (12,7%), and glutamic acid (12.0%). All 6 metabolites were examined with individual receiver operating characteristic (ROC) curve analyses and demonstrated areas-under-the-curve (AUCs) of 0.82–0.91 (P ≤ 0.001) for MBRS status. Several parsimonious combinations of three metabolites increased accuracy of ROC curve analyses to AUCs of 1.00 (P < 0.001), while a combination of volatile organic compounds (VOCs; acetic acid, acetone and methanol) yielded an AUC of 0.98 (P < 0.001). Candidate biomarkers for chronic blast exposure were identified, and if validated in a larger cohort, may aid surveillance and care of military personnel. Future point-of-care screening could be developed that measures VOCs from breath, with definitive diagnoses confirmed with plasma metabolomics profiling.

Proton pump inhibitor use and the risk of peritoneal dialysis associated peritonitis

BACKGROUND

The use of proton-pump inhibitors (PPI) has been associated with an increased risk of developing spontaneous bacterial peritonitis in patients with cirrhosis. Whether PPI use confers a similar risk in developing peritonitis in peritoneal dialysis (PD) patients remains unclear.

METHODS

Patients on PD were retrospectively identified. Data such as PPI use during PD, underlying diagnoses, comorbidities, and baseline serum tests were collected. Univariable and multivariable analysis was conducted using logistic regression to assess whether PPI use and other factors were associated with PD peritonitis.

RESULTS

57 patients were identified with a median(interquartile range(IQR)) age of 65.0(51.5-74.0) years. The median(IQR) time on PD was 29.0(17.5-45.0) months. 28 patients were on a PPI during PD. 57% of the PPI group went on to develop peritonitis, compared to 31% of patients without PPI exposure (OR=2.96, 95% CI:[1.00, 8.78], p=0.050). Months on PD (OR=1.03, 95% CI:[1.00, 1.06], p=0.026), serum urea (OR=0.88, 95% CI:[0.80, 0.97], p=0.017), congestive cardiac failure (OR=5.44, 95% CI:[1.29, 23.00], p=0.021) and renovascular disease (OR=14.59, 95% CI:[1.68, 126.67], p=0.015) were identified as possible risk factors for peritonitis on univariable analysis. Following adjustment for covariates, serum urea, but not PPI use, was associated with PD peritonitis (OR=0.87, 95% CI:[0.78,0.98], p=0.020).

CONCLUSION

PPI use during PD was not associated with peritonitis. Due to the small number of patients and the limited number of studies investigating the effect of PPI use on PD peritonitis, further research is needed. This article is protected by copyright. All rights reserved.

Trends and outcomes of open, laparoscopic, and robotic inguinal hernia repair in the veterans affairs system

PURPOSE

Robotic inguinal hernia repair (RHR) is an evolving technique but is comparatively expensive and has yet to show superior outcomes versus open (OHR) or laparoscopic (LHR) approaches. The utilization and clinical outcomes of RHR have not been reported within the veterans affairs (VA) system. This study analyzes trends in utilization and 30-day post-operative outcomes between OHR, LHR, and RHR in veterans.

METHODS

This is a retrospective review of patients that underwent inguinal herniorrhaphy using the Veterans Affairs Quality Improvement Program database. Multivariable analysis of outcomes was performed adjusting for pre-operative confounding covariates between OHR, LHR, and RHR. Trends in utilization, complication rates, and operative times were also reported.

RESULTS

From 2008-2019, 124,978 cases of inguinal herniorrhaphy were identified: 100,880 (80.7%) OHR, 18,035 (14.4%) LHR, and 6063 (4.9%) RHR. Compared to LHR, RHR was associated with 4.94 times higher odds of complications, 100 min longer mean operative time, and 1.5 days longer median length of stay (LOS). Compared to OHR, RHR was associated with 5.92 times higher odds of complications, 57 min longer mean operative time, and 1.1 days longer median LOS. Utilization of RHR and LHR significantly increased over time. RHR complication rates decreased over time (2008: 20.8% to 2019: 3.2%) along with mean operative times (2008: 4.9 h to 2019: 2.8 h; p < 0.05).

CONCLUSION

While this study demonstrated inferior outcomes after RHR, the temporal trends are encouraging. This may be due to increased surgeon experience with robotics. Further prospective data will elucidate the role of RHR as this technique increases.

Human myelomeningocele risk and ultra-rare deleterious variants in genes associated with cilium, WNT-signaling, ECM, cytoskeleton and cell migration

Myelomeningocele (MMC) affects one in 1000 newborns annually worldwide and each surviving child faces tremendous lifetime medical and caregiving burdens. Both genetic and environmental factors contribute to disease risk but the mechanism is unclear. This study examined 506 MMC subjects for ultra-rare deleterious variants (URDVs, absent in gnomAD v2.1.1 controls that have Combined Annotation Dependent Depletion score ≥ 20) in candidate genes either known to cause abnormal neural tube closure in animals or previously associated with human MMC in the current study cohort. Approximately 70% of the study subjects carried one to nine URDVs among 302 candidate genes. Half of the study subjects carried heterozygous URDVs in multiple genes involved in the structure and/or function of cilium, cytoskeleton, extracellular matrix, WNT signaling, and/or cell migration. Another 20% of the study subjects carried heterozygous URDVs in candidate genes associated with gene transcription regulation, folate metabolism, or glucose metabolism. Presence of URDVs in the candidate genes involving these biological function groups may elevate the risk of developing myelomeningocele in the study cohort.

Accelerating drug development for neuroblastoma - New Drug Development Strategy: an Innovative Therapies for Children with Cancer, European Network for Cancer Research in Children and Adolescents and International Society of Paediatric Oncology Europe Neuroblastoma project

INTRODUCTION

Neuroblastoma, the commonest paediatric extra-cranial tumour, remains a leading cause of death from cancer in children. There is an urgent need to develop new drugs to improve cure rates and reduce long-term toxicity and to incorporate molecularly targeted therapies into treatment. Many potential drugs are becoming available, but have to be prioritised for clinical trials due to the relatively small numbers of patients. Areas covered: The current drug development model has been slow, associated with significant attrition, and few new drugs have been developed for neuroblastoma. The Neuroblastoma New Drug Development Strategy (NDDS) has: 1) established a group with expertise in drug development; 2) prioritised targets and drugs according to tumour biology (target expression, dependency, pre-clinical data; potential combinations; biomarkers), identifying as priority targets ALK, MEK, CDK4/6, MDM2, MYCN (druggable by BET bromodomain, aurora kinase, mTORC1/2) BIRC5 and checkpoint kinase 1; 3) promoted clinical trials with target-prioritised drugs. Drugs showing activity can be rapidly transitioned via parallel randomised trials into front-line studies. Expert opinion: The Neuroblastoma NDDS is based on the premise that optimal drug development is reliant on knowledge of tumour biology and prioritisation. This approach will accelerate neuroblastoma drug development and other poor prognosis childhood malignancies.

A Simple Automated Method for Detecting Recurrence in High-Grade Glioma

Our aim was to develop an automated multiparametric MR imaging analysis of routinely acquired imaging sequences to identify areas of focally recurrent high-grade glioma. Data from 141 patients treated with radiation therapy with a diagnosis of high-grade glioma were reviewed. Strict inclusion/exclusion criteria identified a homogeneous cohort of 12 patients with a nodular recurrence of high-grade glioma that was amenable to focal re-irradiation (cohort 1). T1WI, FLAIR, and DWI data were used to create subtraction maps across time points. Linear regression was performed to identify the pattern of change in these 3 imaging sequences that best correlated with recurrence. The ability of these parameters to guide treatment decisions in individual patients was assessed in a separate cohort of 4 patients who were treated with radiosurgery for recurrent high-grade glioma (cohort 2). A leave-one-out analysis of cohort 1 revealed that automated subtraction maps consistently predicted the radiologist-identified area of recurrence (median area under the receiver operating characteristic curve = 0.91). The regression model was tested in preradiosurgery MRI in cohort 2 and identified 8 recurrent lesions. Six lesions were treated with radiosurgery and were controlled on follow-up imaging, but the remaining 2 lesions were not treated and progressed, consistent with the predictions of the model. Multiparametric subtraction maps can predict areas of nodular progression in patients with previously treated high-grade gliomas. This automated method based on routine imaging sequences is a valuable tool to be prospectively validated in subsequent studies of treatment planning and posttreatment surveillance.

Ethnicity and risk of lower limb amputation in people with Type 2 diabetes: a prospective cohort study

AIM

Lower limb amputation is a serious complication of diabetic foot disease and there are unexplained ethnic variations in incidence. This study investigates the risk of amputation among different ethnic groups after adjusting for demographic, socio-economic status and clinical variables.

METHODS

We used primary care data from a large national multi-ethnic cohort of patients with Type 2 diabetes in New Zealand and linked hospital records. The primary outcome was time from initial data collection to first lower limb amputation. Demographic variables included age of onset and duration since diabetes diagnosis, gender, ethnicity and socio-economic status. Clinical variables included smoking status, height and weight, blood pressure, HbA1c , total cholesterol/HDL ratio and albuminuria. Cox proportional hazards models were used.

RESULTS

There were 892 lower limb amputations recorded among 62 002 patients (2.11 amputations per 1000 person-years), followed for a median of 7.14 years (422 357 person-years). After adjusting for demographic and socio-economic variables and compared with Europeans, Māori had the highest risk [hazard ratio (HR) 1.84 (95%CI:1.54-2.19)], whereas East Asians [HR 0.18, (0.08-0.44)] and South Asians [HR 0.39 (0.22-0.67)] had the lowest risk. Adjusting for available clinical variables reduced the differences but they remained substantial [HR 1.61 (1.35-1.93), 0.23 (0.10-0.56) and 0.48 (0.27-0.83), respectively].

CONCLUSIONS

Ethnic groups had significantly different risk of lower limb amputation, even after adjusting for demographic and some major clinical risk factors. Barriers to care should be addressed and intensive prevention strategies known to reduce the incidence of lower limb amputations could be prioritized to those at greatest risk.

Mindful teaching practice: lessons learned through a hearing voices simulation

A hearing voices simulation (Deegan, 1996) was conducted with mental health nursing students (N = 87) at a large Midwestern university. The goals of this simulation were to change attitudes and decrease stigma. Students used mp3 players to listen to an audio simulation while simultaneously engaging in activities requiring focus and concentration. The Attitude toward Mental Illness Questionnaire (AMIQ; Cunningham, Sobell, & Chow, 1993) was administered pre-and post-simulation and open-ended questions about the experience also were asked. Responses to questions demonstrated increased patience, tolerance, understanding, and empathy among participants. Statistical data demonstrated significant changes in participants post-simulation. However, although students reported increased comfort being around persons hearing voices, they were less likely to acknowledge individual behavior as indicative of recovery. In this article, we discuss how these unexpected outcomes may be related to a subtle illness versus recovery focus. We emphasize how educators must be mindful and reflective about beliefs and attitudes that inform their teaching, and ultimately, their students' learning.

Optimising measles virus-guided radiovirotherapy with external beam radiotherapy and specific checkpoint kinase 1 inhibition

BACKGROUND AND PURPOSE

We previously reported a therapeutic strategy comprising replication-defective NIS-expressing adenovirus combined with radioiodide, external beam radiotherapy (EBRT) and DNA repair inhibition. We have now evaluated NIS-expressing oncolytic measles virus (MV-NIS) combined with NIS-guided radioiodide, EBRT and specific checkpoint kinase 1 (Chk1) inhibition in head and neck and colorectal models.

MATERIALS AND METHODS

Anti-proliferative/cytotoxic effects of individual agents and their combinations were measured by MTS, clonogenic and Western analysis. Viral gene expression was measured by radioisotope uptake and replication by one-step growth curves. Potential synergistic interactions were tested in vitro by Bliss independence analysis and in in vivo therapeutic studies.

RESULTS

EBRT and MV-NIS were synergistic in vitro. Furthermore, EBRT increased NIS expression in infected cells. SAR-020106 was synergistic with EBRT, but also with MV-NIS in HN5 cells. MV-NIS mediated (131)I-induced cytotoxicity in HN5 and HCT116 cells and, in the latter, this was enhanced by SAR-020106. In vivo studies confirmed that MV-NIS, EBRT and Chk1 inhibition were effective in HCT116 xenografts. The quadruplet regimen of MV-NIS, virally-directed (131)I, EBRT and SAR-020106 had significant anti-tumour activity in HCT116 xenografts.

CONCLUSION

This study strongly supports translational and clinical research on MV-NIS combined with radiation therapy and radiosensitising agents.

Attitudes of patients with metastatic breast cancer toward research biopsies

BACKGROUND

Research studies involving human tissue are increasingly common. However, patients' attitudes toward research biopsies are not well characterized, particularly when the biopsies are carried out outside the context of therapeutic trials.

PATIENTS AND METHODS

One hundred sixty patients with metastatic breast cancer (MBC) from two academic (n = 80) and two community (n = 80) hospitals completed a 29-item self-administered survey to evaluate their willingness to consider providing research purposes only biopsies (RPOBs) (as a stand-alone procedure) and additional biopsies (ABs) (additional needle passes at the time of a clinically indicated biopsy).

RESULTS

Eighty-two (51%) of 160 patients would consider having RPOBs, of which 42 (53%) and 40 (50%) patients were from academic and community hospitals, respectively. Patients who had more prior biopsies were less likely to consider RPOBs (RR = 0.6, 95% CI: 0.4-1.0, P = 0.03). Of 160 patients, 115 (72%) patients would consider having ABs. Of these, 64 (80%) and 51 (64%) patients from academic and community hospitals, respectively, would consider ABs (RR = 1.2, 95% CI: 1.0-1.5, P = 0.03).

CONCLUSIONS

Many patients with MBC in both academic and community settings report willingness to consider undergoing biopsies for research. Further research is needed to understand ethical, logistical and provider-based barriers to broader participation in such studies.

A first-in-human phase I trial of AR-12, a PDK-1 inhibitor, in patients with advanced solid tumors

2608

Background: AR-12 (OSU-03012) is an oral celecoxib analogue lacking COX-2 inhibitory activity that inhibits pyruvate dehydrogenase kinase isoenzyme 1 (PDK-1), AKT and impacts the endoplastic reticulum stress pathway. Preclinical studies indicate antitumor activity of AR-12 in various models and enhanced activity in combination. We completed a first in human clinical trial to determine its safety and tolerability, maximum tolerated dose (MTD) and recommended phase II dose (RD). Secondary objectives included assessment of tumor response, pharmacokinetics (PK) and pharmacodynamics (PD) including food effect. Methods: Patients (pts) with advanced solid tumors, ECOG PS 0-1, and adequate organ function were recruited in a modified 3+3 dose-escalation study. Pts received a run-in dose of AR-12 to analyze PK-PD and food effect, followed by continuous daily (QD) dosing in 28-day cycles. A twice daily (BID) cohort was initiated based on safety data. PD analysis was performed in platelet-rich plasma (PRP) and paired tumor biopsies when feasible. Results: 35 pts received at least one dose of study drug; 30 were evaluable for dose limiting toxicities (DLT) at dose ranges 100-3200mg QD and 800-1600mg BID. No DLT were observed in the QD cohort; DLT in the BID cohort are listed in table 1. Drug-related events (NCI-CTCAE v3) included rash (G2-2pts; G3-1pt), fatigue (G2-2pts; G3-4pts), nausea (G2-7pts; G3-1pt) and bloating (G2-1pt). Cmax after single dose was dose-proportional but high PK variability was observed, likely due to inadequate disintegration and dissolution of the formulation in the stomach. At RD, partial GSK3ß inhibition in PRP after 4 hours suggests AKT-pathway modulation. Best response (RECIST v1.0) was stable disease >6 cycles for 2 pts. Conclusions: The RD based on safety data is 800mg BID. Signs of pathway modulation were observed in concordance with the expected mechanism of action but were short-lasting. Considering limited drug absorption and PK variability, a new formulation of the drug will be developed to overcome these limitations. Clinical trial information: NCT00978523. [Table: see text]

Abstract P2-16-04: Attitudes of metastatic breast cancer patients towards research biopsies

Background: In the era of molecularly targeted therapy, developing an understanding of the molecular basis of cancer is a principal or secondary goal of many research studies. For this reason, studies collecting tissue for research purposes are increasingly common. Understanding patients' attitudes towards research biopsies may lead to improvement in accrual to research biopsy studies.

Methods: Patients with metastatic breast cancer from two academic and two community hospitals completed a self-administered paper survey consisting of 29 questions in clinic to evaluate their willingness to consider providing additional biopsies (additional biopsy performed with a clinically indicated biopsy) and research purposes only biopsies (RPOB) (research biopsy performed as a stand alone procedure).

Results: 160 patients (n = 80 academic, n=80 community) completed the survey, with a response rate of 98%. As expected, demographic variables differed between sites, with patients from academic sites likely to be younger (p = 0.01), more educated (p = 0.002), employed (p = 0.01), have prior trial participation (P &lt;0.001) and have a longer travel time (P &lt;0.0001). 64 (80%) academic patients and 51 (64%) community patients would definitely or probably consider additional biopsies. 42 (53%) academic patients and 40 (50%) community patients would consider RPOB.

In univariate analyses of patients' willingness to have additional biopsies, patients in academic sites were more likely to agree to additional biopsies than those at community sites (RR = 1.2, 95% CI 1.0–1.5, p = 0.03). Statistically significant differences based on demographic characteristics such as age, education, marital status, prior trial participation, number of prior biopsies, and travel time were not observed.

For RPOB, patients having had more prior biopsies were less likely to consider research biopsies (RR = 0.6, 95% CI 0.4–1.0, p = 0.03). The following variables did not reach statistical significance: type of practice, age, education, marital status, prior trial participation, and travel time.

Patients' willingness in both academic and community sites to consider RPOB declined with more invasive biopsies. Although differences were observed, none were statistically significant between academic and community; skin (56%, 65%), bone marrow (30%, 27%), breast (43%, 49%) or liver (24%, 19%).

Of the 13/160 (8%) patients who would not consider additional biopsies, the most common reasons cited included pain or discomfort (n = 8/13, 62%), risk of biopsy (n = 8/13, 62%) and anxiety related to the biopsy (n = 6/13, 46%). Of the 37/160 (23%) patients who would not consider RPOB, the most common reasons cited included pain or discomfort (n = 23/37, 62%), risk of biopsy (n = 15/37, 41%) and inconvenience of the procedure to the patient (n = 13/37, 35%).

Conclusions: The majority of patients in this study indicated they would consider research biopsies, with a larger proportion willing to consider additional biopsies; patients seen at academic hospitals were more likely to consider additional biopsies compared to those seen at community hospitals. Breast cancer patients' willingness to undergo research biopsies may be higher than generally expected by clinicians and may not be the primary barrier to obtaining research biopsies.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-16-04.

Exercise in the community for people with minimal gait impairment due to MS: an assessor-blind randomized controlled trial

Background:

While there is an increasing body of evidence supporting the efficacy of exercise in people with multiple sclerosis (MS), additional information on the effectiveness of combining aerobic and resistance training, and yoga is required.

Objectives:

This study evaluated the effectiveness of community exercise interventions for people with MS having minimal gait impairment.

Methods:

A multi-centred, block-randomised, assessor-blinded, controlled trial was conducted. Participants were randomised in groups of eight to physiotherapist (PT)-led exercise ( n = 80), yoga ( n = 77), fitness instructor (FI)-led exercise ( n = 86) and they took part in weekly community-based group exercise sessions. Those in the control group were asked not to change of their exercise habits ( n = 71). The primary outcome was the Multiple Sclerosis Impact Scale (MSIS) 29v2 physical component, measured before and after the 10-week intervention. Secondary outcomes were the MSIS 29v2 psychological component, the Modified Fatigue Impact Scale (MFIS) and the 6-Minute Walk Test (6MWT).

Results:

The group x time interaction approached significance for the MSIS-29v2 physical component ( f = 2.48, p = 0.061) and MFIS total ( f = 2.50, p = 0.06), and it was significant for the MFIS physical subscale ( f = 4.23, p = 0.006). All three exercise interventions led to a statistically significant improvement on the MSIS-29 psychological component and both the MFIS total and physical subscales, which were greater than the control ( p < 0.05). Only the PT-led and FI-led interventions significantly improved the MSIS-29 physical and 6MWT to levels greater than the control ( p < 0.05).

Conclusions:

This study provides evidence for the positive effect of exercise on the physical impact of MS and fatigue. The group nature of the classes may have contributed to the positive effects seen on the psychological impact of MS.

86 EFFECT OF LACTATION ON EMBRYO DEVELOPMENT DURING THE POSTPARTUM PERIOD IN DAIRY COWS

The aim of this study was to examine the effect of lactation and associated metabolic profiles on the ability of the reproductive tract of postpartum dairy cows to support early embryo development. Twenty-one age-matched primiparous Holstein cows were used. Immediately after calving, half of the cows were dried off while the remainder were milked twice daily. To characterise the metabolic profile of the cows, jugular blood samples were taken twice weekly starting 15 days before calving until Day 100 postpartum. At the same time, bodyweight (BW) and body condition score (BCS) were recorded. In Experiment 1, around Day 60 postpartum, the oestrous cycles of all cows were synchronized and sixty-five 2- to 4-cell in vitro-produced embryos were endoscopically transferred on Day 2 (Day 0 = oestrus) to the oviduct ipsilateral to the corpus luteum. On Day 7, the oviduct and uterus were flushed endoscopically and the number of embryos developing to the blastocyst stage was recorded. In Experiment 2, around Day 95 postpartum, cows were re-synchronized and 15 to 20 in vitro-produced blastocysts were transferred to the uterine horn ipsilateral to the corpus luteum. On Day 14, conceptuses were recovered by flushing the reproductive tract at slaughter and were measured. Jugular blood samples were taken daily from Day 0 to 7 (Exp. 1) or 14 (Exp. 2) to measure serum concentrations of progesterone. Data were analysed by ANOVA. Concentrations of NEFA and β-HB were higher (P ≤ 0.05) and glucose, insulin and IGF-1 were lower (P ≤ 0.05) in lactating compared with dry cows. BW and BCS were significantly higher in the non-lactating cows throughout the postpartum period. Recovery rates in both experiments were similar between groups (Exp. 1: 63.9 ± 7.2 vs 65.6 ± 8.6 and Exp 2: 33.3 ± 9.6 vs 39.8 ± 9.6 for dry and milking cows, respectively). In Exp. 1, of the structures recovered, significantly more developed to the blastocyst stage in the dry than in lactating cows (49.3 ± 3.8 vs 32.6.3 ± 4.4, respectively; P ≤ 0.05). Progesterone concentrations did not differ between groups. In Exp. 2, no differences were observed in terms of conceptus dimensions on Day 14 (n = 152). Progesterone concentrations were higher in lactating cows from Day 9 to 14 (P ≤ 0.05). In conclusion, this study provides evidence that at 60 days postpartum, the reproductive tract of lactating cows is compromised in its ability to support early embryo development compared with age-matched parous non-lactating cows; however, by 95 days postpartum there was no apparent difference in conceptus development, consistent with less metabolic stress as indicated by the metabolic profile. Funded by Science Foundation Ireland (SFI/07/SRC/B1156) and the Spanish Ministry of Science and Innovation (AGL2009-11810). VM was supported by an STSM award from the COST Action FAO7O2.

Abstract 5440: Study of the mechanism of action and pharmacodynamic response of JNJ-26481585, a potent histone deacetylase inhibitor in the setting of melanoma

Background: JNJ-26481585 is a potent histone deacetylase (HDAC) inhibitor. It is undergoing evaluation in phase I trials in solid tumours. The drug has shown plasma concentrations consistent with activity in preclinical models and target inhibition in surrogate and tumour tissue.

Purpose: To determine the mechanism of action of JNJ-26481585 and to study factors determining sensitivity to the drug in-vitro in the setting of melanoma cell lines.

Experimental Procedures: Array comparative genomic hybridization (array CGH) was carried out to study gene copy number. The growth inhibitory (GI50) concentrations of JNJ-26481585 and 17-allylamino, 17-demethoxygeldanamyin (17-AAG) were determined by sulforhodamine (SRB) assays. A panel of melanoma cell lines was exposed to GI50 and 5 X GI50 for 24hrs and gene expression profiling was performed using gene expression microarrays. Changes in protein expression were studied by western blot analysis.

Results: Cells exposed to GI50 and 5X GI50 of 17-AAG for 24hrs showed a molecular signature of HSP90 inhibition including C-RAF depletion and HSP70 induction while this was not the case in equitoxic concentrations of JNJ-26481585. In addition, JNJ-26481585 did not reproducibly induce acetylation of tubulin which is a surrogate for cytoplasmic acetylation of proteins such as HSP90. JNJ-26481585 however induced robust acetylation of histone H3 suggestive of its mechanism of action predominantly as a class I HDAC inhibitor. The micropthalmia associated transcription factor (MITF) locus was amplified in the SKMEL-28 cells. The GI50 concentrations of JNJ-26481585 in the cell lines SKMEL-28, WM266.4, A2058, SKMEL-2 and SKMEL-5 were 5.4 (SD 0.86) nM, 20 (SD 0.58) nM, 28.1 (SD 0.7) nM, 30.4 (SD 3.6) nM, 33.4 (SD 3.6) nM respectively. The cell line panel was exposed to GI50 and 5 X GI50 of JNJ-26481585 for 24hrs. Protein levels of MITF was depleted in addition to MITF m-RNA levels being significantly reduced; p=0.002 (Welch T test with Benjamini and Hochberg correction for multiple testing; FDR 5%) at the time points studied, suggesting down regulation of MITF gene expression as a possible mechanism of action of JNJ-26481585. All the cell lines studied underwent apoptosis as evidenced by demonstration of cleaved PARP on western blotting.

Conclusions: In this model, the mechanism of action of JNJ-26481585 is not predominantly due to HSP90 inhibition caused by acetylation of HSP90 in melanoma cells. Melanoma cell lines which have an amplification of MITF are sensitive to the HDAC inhibitor JNJ-26481585. Further exploration of MITF protein to evaluate pharmacodynamic response of JNJ-26481585 is warranted.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5440.

Effect of rifampin on the pharmacokinetics of Axitinib (AG-013736) in Japanese and Caucasian healthy volunteers

PURPOSE

Axitinib, a potent and selective inhibitor of vascular endothelial growth factor receptors 1, 2, 3, is metabolized by cytochrome P450 3A4 and glucuronidation. This study evaluated the effect of rifampin, a potent inducer of drug-metabolizing enzymes, on axitinib plasma pharmacokinetics. Equal numbers of Japanese and Caucasian subjects were enrolled to assess the potential differences in axitinib pharmacokinetics between the two ethnicities.

METHODS

Forty healthy volunteers were randomized to receive 5 mg axitinib alone and with 600 mg rifampin.

RESULTS

Rifampin expectedly decreased AUCinf and Cmax of axitinib (geometric mean reduced by 79 and 71%, respectively). However, differences in axitinib pharmacokinetics were not observed between Japanese and Caucasian subjects (geometric mean ratios for axitinib treatment alone for AUCinf and Cmax were 103 and 96%).

CONCLUSIONS

The results support a common axitinib starting dose in both populations. Potent inducers of drug-metabolizing enzymes reduce axitinib exposure and dose adjustments may be needed for optimal efficacy.

Abstract C208: CCT129254 (AT11854) is a well tolerated, orally bioavailable inhibitor of AKT/PKB with pharmacodynamic and antitumor activity in a range of xenograft models

The PI3K/AKT/mTOR pathway is the most frequently deregulated pathway in human cancer. The serine/threonine kinase AKT (PKB), a member of the AGC family of protein kinases, is central to this pathway and is considered an important target for cancer therapy. However, the development of well tolerated, orally bioavailable inhibitors of catalysis targeting this enzyme has proved challenging and there are currently no such agents that have progressed to phase II clinical studies. We have characterised the pharmacodynamic and anti-tumor activity of CCT129254, a small molecule inhibitor of AKT. CCT129254 was well tolerated when dosed chronically at up to 200 mg/kg qd in nude mice. Acute doses of 100–200 mg/kg CCT129254 caused dose-dependent transient elevations of blood glucose concentration and inhibition of AKT substrate phosphorylation in xenografts. An acute dose of 200 mg/kg qd CCT129254 significantly reduced pGSK3 for &gt;6h in U87-MG xenografts, and this pharmacodynamic activity correlated with plasma drug concentration. Moreover, chronic dosing of CCT129254 caused a dose-dependent inhibition of tumor growth in this model. Chronic once daily dosing of CCT129254 significantly inhibited tumor growth in 14 of 16 other xenograft models, including breast, prostate, lung, ovarian, kidney and colon. The highest single agent activity was seen in two breast cancer xenografts (BT474c and HCC-1954). Significant activity was also seen in the gefitinib-resistant NCI-H1975 NSCLC model with respectively activating and resistance L858R and T790M mutations in EGFR. Increased efficacy is also seen when CCT129254 is combined with the cytotoxic agents cisplatin, doxorubicin and taxotere in xenograft models. CCT129254 exemplifies an oral, well tolerated inhibitor of AKT catalysis with the potential to inhibit the growth of a wide range of solid tumors both as monotherapy and in combination with cytotoxic agents.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C208.

Diastolic blood pressure (dBP) and pharmacokinetics (PK) as predictors of axitinib efficacy in metastatic renal cell cancer (mRCC)

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Background: Axitinib (AG-013736) is an oral, potent, and selective inhibitor of VEGF receptors 1, 2, 3. An association between dBP elevation and clinical outcome has been previously reported (Rini, ASCO. 2008). The objective of this pooled analysis of two phase II mRCC studies was to explore the relationship between PK, dBP, and clinical efficacy. Methods: PK data from two phase II studies in cytokine-refractory mRCC patients (pts) and 8 single-dose healthy volunteer (HV) studies were included (n = 109 mRCC pts and 240 HV) in the population PK analysis; the efficacy analysis included mRCC pts only. PK data was analyzed using nonlinear mixed-effects modeling to estimate population PK parameters (mean and inter-individual variability). Mean steady-state area under the plasma concentration-time curve (AUC) at the end of cycle 1 and the dBP during axitinib therapy were utilized as predictors of clinical efficacy in the mRCC pts using logistic regression and Kaplan-Meier analyses. Results: The median overall survival (mOS) for mRCC pts with at least 1 dBP measurement ≥90 mmHg (n = 59) during axitinib therapy was 130 weeks vs. 42 weeks (p < 0.01) for pts without any dBP ≥90 mmHg (n = 50). The mOS of pts with an AUC below the median (605 ng.hr/ml; n = 54) was 69 weeks vs. 88 weeks (p > 0.05) for pts with an AUC above the median (n = 55). Among pts with dBP ≥90 mmHg, mOS was 120 weeks and 131 weeks (p > 0.05) for pts with AUC below and above the median (n = 23 and 36), respectively. Among pts without dBP ≥90 mmHg, mOS was 42 weeks and 43 weeks (p > 0.05) for pts with AUC below and above the median (n = 31 and 19), respectively. An 82% increase in probability of a partial response was predicted for a 10 mmHg higher dBP during therapy. There was no apparent correlation between the AUC and maximum dBP during axitinib therapy. Conclusions: dBP ≥90 mmHg during axitinib therapy is a strong predictor of clinical efficacy in patients with mRCC, and is not merely a reflection of higher axitinib drug levels. These data support an ongoing pivotal phase III trial in previously treated mRCC that incorporates a dose-titration scheme based on patient tolerance and BP.

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Pharmacokinetics/genotype associations for major cytochrome P450 enzymes in native and first- and third-generation Japanese populations: comparison with Korean, Chinese, and Caucasian populations

Application of foreign clinical data across geographic regions can accelerate drug development. Drug disposition can be variable, and identification of factors influencing responsible pharmacokinetic/pharmacogenomic approaches could facilitate the universal application of foreign data and reduce the total amount of phase III clinical trials evaluating risks in different populations. Our objective was to establish and compare genotype (major cytochrome P450 (CYP) enzymes)/phenotype associations for Japanese (native and first- and third-generation Japanese living abroad), Caucasian, Chinese, and Korean populations using a standard drug panel. The mean metabolic ratios (MRs) for the four ethnic groups were similar except for a lower activity of CYP2D6 in Caucasians and CYP2C19 in Asians. Genotype, not ethnicity, impacted the MR for CYP2C9, CYP2C19, and CYP2D6; neither affected CYP1A2, CYP2E1, and CYP3A4/5 activities. We conclude that equivalent plasma drug concentrations and metabolic profiles can be expected for native Japanese, first- and third-generation Japanese, Koreans, and Chinese for compounds handled through these six CYP enzymes.

Comparison of selected skin decontaminant products and regimens against VX in domestic swine

An anesthetized domestic swine model was used to compare the efficacy and cross-contamination potential of selected skin decontaminant products and regimens against the chemical warfare agent, VX. Animals topically exposed to 2×, 3× or 5× LD50 VX showed typical signs of organophosphate nerve agent poisoning, including miosis, salivation, mastication, dysrhythmias, and respiratory distress prior to death. Animals were exposed to 5× LD50 VX and then decontaminated 45 min later with the reactive skin decontamination lotion (RSDL®), Fuller’s earth (FE), 0.5% hypochlorite, or soapy water. Survival was 100% when the reactive skin decontamination lotion or FE was utilized, although 50% of Fuller’s earth-decontaminated animals exhibited serious signs of VX poisoning. Decontamination of VX-treated animals with 0.5% hypochlorite was less effective but also increased survival. Soapy water was ineffective in preventing lethality. Blood cholinesterase levels were not predictive of clinical outcome in decontaminated animals. The potential of “decontaminated” VX in open wounds to cause poisoning was assessed by vigorously mixing 5× LD50 VX with the test decontaminants for 5 min and then placing the mixture onto a full-thickness skin wound. Soapy water was ineffective in preventing lethality. Although treatment with dry Fuller’s earth prevented death and all signs of organophosphate poisoning, a significant proportion of treated animals decontaminated with Fuller’s earth in aqueous suspension exhibited serious signs of organophosphate poisoning, suggesting that live agent may be desorbed from Fuller’s earth when it is exposed to a liquid environment. Animals treated with reactive skin decontamination lotion or 0.5% hypochlorite-VX mixtures showed no signs of organophosphate poisoning during the 6- h test period.

No evidence for epigenetic inactivation of fumarate hydratase in leiomyomas and leiomyosarcomas

Germline mutations in Fumarate Hydratase (FH) cause the development of leiomyomas and leiomyosarcomas in the syndromes Multiple Cutaneous and Uterine Leiomyomata (MCUL1) and Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC). There is little evidence, however, that FH mutation plays a role in the development of sporadic leiomyomas or leiomyosarcomas. Such observations do not, however, exclude a role for FH in tumour development outside the context of MCUL1/HLRCC, as it is possible that FH expression could be silenced by epigenetic mechanisms. To explore this possibility we have developed a highly specific antibody to FH and analysed a series of forty-five fresh-frozen uterine leiomyomas and nine leiomyosarcomas for FH expression.

Clinical anticancer drug development: targeting the cyclin-dependent kinases

Cell division involves a cyclical biochemical process composed of several step-wise reactions that have to occur once per cell cycle. Dysregulation of cell division is a hallmark of all cancers. Genetic and epigenetic mechanisms frequently result in deranged expression and/or activity of cell-cycle proteins including the cyclins, cyclin-dependent kinases (Cdks), Cdk inhibitors and checkpoint control proteins. The critical nature of these proteins in cell cycling raises hope that targeting them may result in selective cytotoxicity and valuable anticancer activity.

Oral tobacco cessation with UK resident Bangladeshi women: a community pilot investigation

Our objective was to establish the short-term outcomes for successful tobacco cessation of a programme offering UK resident Bangladeshi women chewing paan with tobacco nicotine replacement therapy (NRT) in addition to brief advice and encouragement alone. We used a short-term longitudinal, quasi-experimental study design, in the setting of two local authority housing estates in Tower Hamlets, London. Bangladeshi women volunteers were recruited following presentations to community groups. The volunteers were assigned, after matching for age, number of paan with tobacco chewed daily and medical screening, to receive one of two tobacco cessation interventions (NRT with brief encouragement and advice, and brief advice and encouragement alone). The main outcome measures were changes in tobacco use and nicotine dependence, assessed by questionnaire and intake measures, adverse effects, and withdrawal symptoms. In total, 130 volunteers were recruited. Their mean age was 42.5 years (SD = 11.3). Mean number of paan quid with tobacco chewed daily was 10.7 (SD = 9.3) and the average age of starting to add tobacco to paan was 24 years (SD = 12). Ninety-one percent completed the 4-week trial. We found that 19.5% had stopped tobacco use, of whom 22% had received NRT, and 17% brief advice and encouragement alone. The successful members of the NRT group made a significantly greater reduction in their salivary cotinine scores at final review compared to baseline. Oral pain was reported as a barrier to successful oral tobacco cessation by 62% of the volunteers at final review. We conclude that methods identified as helping tobacco smokers successfully stop smoking can be used with Bangladeshi women chewing paan with tobacco. More research is needed to investigate these short-term outcomes and to explore the particular barriers to successful cessation for this group such as oral pain.

Functional instability of the ankle: differences in patterns of ankle and knee movement prior to and post landing in a single leg jump

The aim of this study was to investigate motor control in subjects with functional instability of the ankle joint. This was achieved by analysing patterns of lower extremity motion prior to and immediately following landing during single leg jumping in subjects with functional instability of the ankle. Fourteen subjects with unilateral functional instability and 10 healthy control subjects performed single leg jumps from a 40 cm height whilst angular displacement of their ankle and knee joints were recorded. Subjects with functional instability demonstrated significantly greater ankle dorsiflexion over the period encompassing 10 ms pre landing to 20 ms post landing (p < 0.05). They also exhibited a significantly greater level of knee flexion than controls over the period from 20 ms pre landing to 60 ms post landing (p < 0.05). The timing of these significant differences leads us to conclude that they do not arise as a result of reflexively mediated peripheral events following landing.

Increased H(max):M(max) ratio in community walkers poststroke without increase in ankle plantarflexion during walking

OBJECTIVE

To investigate whether changes in H-reflex response at midswing and midstance are related to excessive plantarflexion during walking in community walkers poststroke compared with control subjects without stroke.

DESIGN

Survey of functional walking handicap in a random sample of an annual stroke cohort followed by H-reflex and M(max) testing of a smaller sample.

SETTING

Community and laboratory testing.

PARTICIPANTS

Forty individuals with stroke (IWS group) completed the functional walking handicap survey, 10 of whom agreed (with 10 age-matched controls) to enroll in a study of of the H(max):M(max) ratio in soleus during walking.

INTERVENTION

Electromyography during treadmill walking.

MAIN OUTCOME MEASURES

Functional Walking Handicap Scale, soleus H(max):M(max) ratio, and the ankle joint's angle of displacement.

RESULTS

Nine of the 10 stroke patients were community walkers. All had significantly (p <.05) more variable ankle movement during walking than the controls. The H(max):M(max) ratio was significantly (p <.01) increased in the IWS group because of a decrease in M(max) response without significant (p >.05) increase in H(max) response.

CONCLUSIONS

Individuals with community-level walking ability after stroke have significantly (p <.05) less repeatability of ankle joint movement than controls at both midswing and midstance. Simultaneous soleus H(max) and M(max) testing showed a significant (p <.01) reduction in the H(max) and H(max):M(max) ratio at midswing in controls only. This inhibition at midswing was lost by the IWS group without significant increase in H(max), suggesting that central synaptic excitability was within the normal range, and possibly accounting for the absence of excessive ankle plantarflexion during walking in the IWS group with community level walking ability.

Current use of outcome measures for stroke and low back pain rehabilitation in five European countries: first results of the ACROSS project

Objectives were to obtain a view on the current use of outcome measures for stroke and low back pain rehabilitation in five European countries. A postal questionnaire, comparable for different cultural situations, was distributed in August 1998 to 581 rehabilitation facilities in Ireland, Germany, Italy, Austria and the Netherlands. Of these, 102 settings responded. In stroke rehabilitation the Barthel Index is the dominant outcome measure, followed by the Functional Independence Measure and the Frenchay Activities Index. Besides the Visual Analogue Scale, the most used outcome measures in low back pain rehabilitation were the Oswestry Pain Disability Questionnaire and the Roland Disability Questionnaire. Outcome measures are more frequently used in stroke than in low back pain rehabilitation. The purpose of use is mainly for the measurement of effectiveness, while a relation with quality management is seldom made. There appears to be little agreement on which outcome measures to use. Little attention was found to have been given to the assessment of handicap, quality of life and patient satisfaction.

Semantic factors in the production of number agreement

This paper examines the role of semantic factors in the production of subject-verb number agreement. As an ostensibly grammatical process, number agreement provides an interesting case for examining the flow and interaction of semantic and syntactic information through the language-production system. Using a sentence-completion task, agreement errors can be elicited from subjects by presenting them with sentence fragments containing a complex noun-phrase, in which the nonhead noun is plural (e.g., The key to the cabinets ... WERE missing.). Previous research has demonstrated that the probability of making an error can be affected by varying the properties of the nouns in the complex noun phrase. By investigating which variables do and do not affect error rates, constraints on the flow of information through the production system can be inferred. In three experiments, we investigated the possible effects of three different semantic manipulations of the nouns in the complex NP: animacy, semantic overlap, and plausibility of modification by the sentence predicate. We found that both animacy and semantic relatedness had reliable effects on error rates, indicating that the mechanism involved in implementing agreement cannot be blind to semantic information. However, the plausibility with which each noun could serve as the subject of the sentence predicate had no effect on error rates. Taken together, these results suggest that while semantic information is visible to the agreement mechanism, there are still constraints on when this information can affect the process. Specifically, it may be the case that only information contained within the complex NP is considered for the purposes of implementing agreement.

Pyrido[2,3-d]pyrimidin-7-one inhibitors of cyclin-dependent kinases

The identification of 8-ethyl-2-phenylamino-8H-pyrido[2, 3-d]pyrimidin-7-one (1) as an inhibitor of Cdk4 led to the initiation of a program to evaluate related pyrido[2, 3-d]pyrimidin-7-ones for inhibition of cyclin-dependent kinases (Cdks). Analysis of more than 60 analogues has identified some clear SAR trends that may be exploited in the design of more potent Cdk inhibitors. The most potent Cdk4 inhibitors reported in this study inhibit Cdk4 with IC(50) = 0.004 microM ([ATP] = 25 microM). X-ray crystallographic analysis of representative compounds bound to the related kinase, Cdk2, reveals that they occupy the ATP binding site. Modest selectivity between Cdks is exhibited by some compounds, and Cdk4-selective inhibitors block pRb(+) cells in the G(1)-phase of the cell division cycle.

Phase-dependent inhibition of H-reflexes during walking in humans is independent of reduction in knee angular velocity

The purpose of this investigation was to investigate whether reduction in impulses arising from stretch of the quadriceps by restricting rapid knee flexion in early swing would affect inhibition of the H-reflex during swing. The contribution of afferent input arising from knee angular velocity to phase-dependent modulation of short-latency responses in the soleus was studied by simultaneously measuring joint velocity and soleus H-reflex responses at midstance and midswing phases of treadmill walking in 15 normal subjects. Stimulus strength was varied so that both maximal M and H waves were identified in each subject at midswing and midstance with the knee unrestricted (UK) and with knee movement restricted (RK), using a full leg bivalved cast to immobilize the knee joint. All subjects exhibited short-latency reflex responses in the soleus muscle. The H/M ratio at midswing was significantly reduced compared with midstance under both UK and RK walking conditions (P < 0.0001). When compared with UK walking, knee joint angular velocity during RK walking was significantly reduced at midswing (P < 0.001) and midstance (P < 0.005) compared with UK. There were, however, no significant differences in H/M ratios at midswing and midstance between UK and RK walking tests. Inhibition of the H-reflex in the soleus muscle during swing was not affected by significant reduction in knee angular velocity. These results indicate that the sensory input from changes in angular velocity at the knee does not lay the inhibitory foundation of phase-related reflex modulation in the ankle extensors during walking as suggested by Brooke and colleagues.

Glaucoma patients demonstrate faulty autoregulation of ocular blood flow during posture change

BACKGROUND/AIMS

Autoregulation of blood flow during posture change is important to ensure consistent organ circulation. The purpose of this study was to compare the change in retrobulbar ocular blood flow in glaucoma patients with normal subjects during supine and upright posture.

METHODS

20 open angle glaucoma patients and 20 normal subjects, similar in age and sex distribution, were evaluated. Blood pressure, intraocular pressure, and retrobulbar blood velocity were tested after 30 minutes of sitting and again after 30 minutes of lying. Retrobulbar haemodynamic measures of peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were obtained in the ophthalmic and central retinal arteries using colour Doppler imaging (CDI).

RESULTS

When changing from the upright to supine posture, normal subjects demonstrated a significant increase in OA EDV (p = 0.016) and significant decrease in OA RI (p = 0.0006) and CRA RI (p = 0.016). Glaucoma patients demonstrated similar changes in OA measures of EDV (p = 0.02) and RI (p = 0.04), but no change in CRA measures.

CONCLUSION

Glaucoma patients exhibit faulty autoregulation of central retinal artery blood flow during posture change.

Dorzolamide, visual function and ocular hemodynamics in normal-tension glaucoma

The purpose of this study was to determine how a topical carbonic anhydrase inhibitor, dorzolamide, alters visual function and ocular blood flow in persons with normal-tension glaucoma. Eighteen normal tension glaucoma patients, after washout of other ocular medications, were treated for four weeks with 2% dorzolamide, three times daily. A control group of eleven other normal-tension glaucoma patients received placebo eye drops. Patients were studied before treatment, and after two and four weeks of treatment. Each study included assessment of central visual function (contrast sensitivity), intraocular pressure (IOP), and several aspects of ocular hemodynamics, including measures of retinal arteriovenous passage time, retinal arterial and venous diameters, and flow velocities in the ophthalmic, central retinal, and posterior ciliary arteries. Dorzolamide significantly reduced IOP at two and four weeks (each p<0.01), and at the same time increased contrast sensitivity at both three and six cycles per degree (each p<0.05). Neither of these variables changed significantly in the control group. Dorzolamide also accelerated retinal arteriovenous passage time of fluorescein dye, at constant retinal arterial and venous diameters (p<0.05), but failed to change flow velocities in any retrobulbar vessel. The ability of dorzolamide to improve contrast sensitivity in persons with normal-tension glaucoma may be related to either IOP reduction or altered ocular perfusion.