OP0145 MALIGNANCY IN ANCA-ASSOCIATED VASCULITIS AND POLYARTERITIS NODOSA: AN AUSTRALIAN POPULATION-BASED STUDY

Background:

The increased risk of malignancy in patients with ANCA-associated vasculitis (AAV) and polyarteritis nodosa (PAN) has been attributed to late treatment related effects, with non-melanoma skin and genitourinary cancers most frequently reported in European studies1,2,3. Malignancy has not been examined in patients with AAV/PAN in Australia, where environmental factors may influence risk.

Objectives:

To determine the risk and timing of incident cancer in Western Australian (WA) AAV/PAN patients compared to controls.

Methods:

Patients and controls were ascertained through the WA Hospital Morbidity Data collection System (HMDS). Administrative hospitalisation data were linked with the WA cancer and death registries. Data was available between 1980-2015. Patients were classified into two sub-groups using International Classification of Disease (ICD) -9 and/or -10 codes: (1) GPA/MPA- granulomatosis with polyangiitis (GPA)/microscopic polyangiitis (MPA), and (2) other-AAV/PAN- eosinophilic granulomatosis with polyangiitis (EGPA), PAN, and other patients with any AAV or PAN where more specific ICD-10 coding was not available. Controls were age, sex and temporally matched (at patient diagnosis date) and had no rheumatological diagnosis. Patients and controls with prior cancer were excluded from the analysis.

Spline-based estimation of time-varying hazard ratios (HR) for incident cancer in patientsvscontrols was performed using the Stata library stpm2cr4. Results for cause-specific models, which treated deaths in patients without cancer as censored, were confirmed using models treating death as a competing risk. The risk of specific cancers was analysed by Cox regression.

Results:

The analysis included 391 patients (165 GPA/MPA, 217 other-AAV/PAN) and 4913 controls, with 86 incident cancers (over 3556.7 person-years) observed in patients and 1119 (over 64997.0 person-years) in controls. Patients and controls were well matched for age (mean ± standard deviation GPA/MPA: 55 ± 18 years, other AAV/PAN: 59 ± 17 years, controls 57 ± 16 years), and sex (female: GPA/MPA 48%, other AAV/PAN 46%, controls 46%).

Incident cancer risk and timing differed between the two patient subgroups (Figure 1). The risk of incident cancer in GPA/MPA patients, compared to controls, increased with disease duration, whilst other-AAV/PAN patients had a greater risk within the first two years of diagnosis, but a similar risk to controls in the longer term.

By specific cancers, GPA/MPA patients had an increased risk of skin cancers (excluding squamous and basal cell carcinomas): hazard radio (HR) 2.71 95% confidence interval (CI) 1.55 – 4.74, and genitourinary cancers: HR 3.64, 95% CI 1.58, 8.39, which was not observed in other-AAV/PAN patients. While there was trend for an overall increase in haematological cancers, this was inconclusive.

Conclusion:

Incident cancer risk, driven by skin and genitourinary cancers, increased with disease duration in GPA/MPA patients, consistent with previous studies, suggestive of a treatment related effect. In contrast, cancer was more frequently observed early after diagnosis in other-AAV/PAN patients. Our findings suggest that vigilance for incident cancers is required for all patients with AAV and PAN after diagnosis and in long term management, considering distinct periods of greater risk by disease subgroup.

References:

[1]Heijl C et al. Ann Rheum Dis 2011;70:1415-1421

[2]Lafarge A et al. Ann Rheum Dis 2019;0:1-2

[3]Farschou M et al. Rheumatology 2015;54:1345-1350

[4]Mozumder S et al. Stata J. 2017;17(2):462-489

Disclosure of Interests:

Joanna Tieu: None declared, Susan Lester: None declared, Warren Raymond: None declared, Helen Keen Speakers bureau: Pfizer Austrlaia, Abbvie Australia, Catherine Hill: None declared, Johannes (“Hans”) Nossent Speakers bureau: Janssen

FRI0192 MORTALITY IN IGA VASCULITIS: A LONGITUDINAL POPULATION-BASED STUDY

Background:

There is sparse population-level data on outcome in patients with Immunoglobulin-A vasculitis (IgAV) and none from Australia

Objectives:

We compared long-term mortality for paediatric and adult IgAV patients with age- and gender-matched controls.

Methods:

Linked health data for pediatric (<20 years=473) and adult (20+ years, n=267) IgAV patients were obtained from state-wide hospital and deaths registries in Western Australia for the period 1980-2015. All-cause mortality rates (MR) (deaths/1000 person-years) were compared with controls using mortality rate ratios (MRR) and with the general population of Western Australia by standardised mortality rate ratios (SMRR) with Poisson derived 95% confidence intervals (CI). We used Kaplan-Meier survival estimates and multivariate Cox regression derived hazard ratios (HR) for time dependent analyses.

Results:

In pediatric patients (mean age 7.2 years, 60 % male) MRR was 1.27 (CI: 0.34-4.08, p=0.68) and SMRR was 2.31 (CI: 0.72-5.7, p=0.47) (Table 1) with a 20-year survival rate (>99%) similar to controls. Despite higher rates of renal failure (1.5% vs 0.2%, p=0.002) deaths in pediatric IgAV patients were mainly from unrelated causes. In adult IgAV patients (mean age 55.8 years, 48% males) MMR was 2.06 (CI 1.70-2.50, p<0.01) and SMRR 6.16 (3.04 -14.3, p<0.01) (Table) during a mean of 19.5 years follow-up with significantly reduced survival at five (72.7 vs. 89.7 %) and twenty years (45.2% vs. 65.6 %) (p<0.05). Renal disease (HR: 1.47, CI 1.04 - 2.06), the presence of any comorbidity (HR:1.30, CI 1.23 - 1.37) and male gender (HR:1.23; CI 1.04 - 1.47) were independent predictors of death. While cardiovascular events (34.2%) and malignancy (19.4%) were the most frequent causes of death, only death from infections (5.8 vs 1.8%, p=0.02) and renal disease (3.6 vs 1.8%, p=0.03) were more frequent in adult IgAV patients than controls.

Mortality data for childhood and adult-onset IgAV patients and controls. Figures indicate mean (±SD), numbers (%) or rate/1000 patient months (95% CI)

PediatricAdultIgAVControlsP valueIgAVControlsPMean follow-up (yrs)22.71 (±5.2)23.75 (±3.17)0.00111.9 (±9.04)15.94 (±8.30)0.001Non-survivors (%)<5 (0.8)9 (0.9)0.5137 (51.3)394 (33.4)<0.001Person-years1027529520317818815MR0.39 (0.1, 0.9)0.30 (0.1, 0.5)43.11 (36,1,50.9)20.94 (18.9, 23.1)MRR1.27 (0.34, 4.08)0.672.06 (1.70, 2.50)<0.001SMRR2.31 (0.71, 5.71)0.716.16 (3.04, 14.3)<0.001

Conclusion:

Compared to controls and general population, mortality risk was not increased in paediatric IgAV patients for at least 20 years following diagnosis despite a higher rate of end stage renal failure. However, in adult IgAV patients, all-cause mortality risk was six times higher than in the general population leading to significantly reduced five-year survival, especially for male patients with comorbidity including renal disease.

Acknowledgments:

The authors thank the Data Custodians of the Hospital Morbidity Data Collection (HMDC), Emergency Department Data Collection (EDDC), the Western Australian Cancer Registry (WACR), the State Registry of Births, Deaths and Marriages, the WA Electoral Commission, and the NCIS for use of the CODURF dataset, and the staff at Data Linkage Branch at the Western Australian Department of Health for their assistance in provision of data. This work was supported by an unrestricted grant from the Arthritis Foundation of Western Australia. Author WDR received a PhD Scholarship in Memory of John Donald Stewart from the Arthritis Foundation of Western Australia.

Disclosure of Interests:

Johannes (“Hans”) Nossent Speakers bureau: Janssen, Milica Ognjenovic: None declared, warren raymond: None declared, Helen Keen Speakers bureau: Pfizer Austrlaia, Abbvie Australia, Charles Inderjeeth Consultant of: Linear Research Perth, David Preen: None declared

Nossent J. AB1221 POPULATION WIDE STUDY OF MORTALITY IN ANCA-ASSOCIATED VASCULITIS IN WESTERN AUSTRALIA FROM 2000 TO 2014

Background:

Survival in ANCA-associated vasculitis (AAV) has improved substantially in the last fifty years, but Australian data and studies with a control population are scarce.

Objectives:

The aim of this study was to compare the all-cause mortality rate between patients with AAV and matched controls in Western Australia.

Methods:

A retrospective population-based cohort study conducted using the Western Australia Health Data Linkage System (WADLS) for patients with a diagnostic code for AAV (International Classification of Diseases (ICD)-10-AM M30.1, M31.3 and M31.7). We included 240 patients with AAV (mean age 57.37 ± 16.69, 48.8% males) who had a hospital admission or emergency department visit between 1 January 2000 and 31 December 2014 and 4406 controls matched for age and sex. Death details were obtained from the WA Death registry. Mortality rates per 1000 person-years (MR) for AAV patients and controls were compared by mortality rate ratios (MRRs) with 95% CI. Kaplan Meijer survival estimates were analyzed by log-rank test.

Results:

During a mean follow-up of 6.58 years (3.37, 11.25) 83 incident AAV patients (34.6%) died, giving a mortality rate of 48.13 per 1000 person-years (95% CI 38.33, 59.66). This was 82% higher overall than in controls (MRR 1.82, 95% CI 1.46, 2.26, P < 0.0001), while the MRR for males with AAV was 2.28 (95% CI 1.46, 2.26; P < 0.0001) and for females 1.43 (95% CI 1.01, 2.02; P = 0.0267). Survival estimates at one (90.5%) and five years (75%) were significantly lower in AAV patients than controls.

Conclusion:

Over the last fifteen years, the mortality risk for AAV patients remains significantly increased compared with matched controls and more so for male than female AAV patients. Together with the reduced one- and five-year survival rate, this indicates the need for further improvements in initial disease management in order to reduce the risk of death in AAV.

Table

Mortality rates (MR) per 100 patient years and Mortality rate ratio (MRR) with 95% CI in patients with AAV and controls

AAVControlDeathsPersonyearsMR(95% CI)DeathsPersonyearsMR(95% CI)MRR(95% CI)All83172448.1(38.3, 59.6)12194606926.4(25.0, 27.9)1.82 (1.46, 2.26)Male4978962.1(45.9 82.0)6902529528.2(25.2, 29.3)2.28 (1.72, 3.02)Female3493536.3(25.1, 50.7)5292077325.4 (23.3, 27.7)1.43 (1.01, 2.02)Figure.

Kaplan Meyer Survival curves for AAV patients and controls

Acknowledgments:

The authors thank the Data Custodians of the Hospital Morbidity Data Collection (HMDC), Emergency Department Data Collection (EDDC), the State Registry of Births, Deaths and Marriages, the WA Electoral Commission, and the staff at Data Linkage Branch at the Western Australian Department of Health for their assistance in provision of data. This work was supported by an unrestricted grant from the Arthritis Foundation of Western Australia. Author WDR received a PhD Scholarship in Memory of John Donald Stewart from the Arthritis Foundation of Western Australia

Disclosure of Interests:

Wade Taylor: None declared, warren raymond: None declared, Helen Keen Speakers bureau: Pfizer Austrlaia, Abbvie Australia, Charles Inderjeeth Consultant of: Linear Research Perth, David Preen: None declared, Johannes (“Hans”) Nossent Speakers bureau: Janssen

SAT0594 LONG-TERM MORBIDITY FOLLOWING IGA VASCULITIS IN CHILDHOOD

Background:

IgA vasculitis (IgAV) in children is considered a mostly self-limiting disease. However, patients may require aggressive initial treatment, are prone to disease relapses and conceivably have a sustained abnormality in mucosal and /or circulating IgA responsiveness, that can predispose to the development of other conditions.

Objectives:

To determine whether childhood IgAV predisposes to comorbidity later in life.

Methods:

Observational cohort study examining rates of hospitalization, ED visits, procedures and accrual of comorbidity (by Charlson comorbidity index; CCI) comparing 494 IgAV patients <20 years at diagnosis with 1385 non-exposed matched controls over a 20-year period. Maximum likelihood estimates were used to obtain Odds (OR) and Rate ratios per 1000 person-years (RR).

Results:

Hospitalization was increased proportionally (73.5 vs 51.5%) and by rate (21.7 vs 18.9; rate ratio 1.15) (both p<0.01) for IgAV patients, who underwent more diagnostic and medical procedures whereas controls had higher rates of surgical interventions. IgAV patients had an higher overall ED attendance (25 vs 16%) and visit rate (10.8 vs 8.43, RR 1.29) (each p<0.01)) and accrued more often peptic ulcer and renal disease and developed severe comorbidity (CCI ≥3) at a higher rate (OR 2.9, 95% CI 0.79-11.6) than controls.

Conclusion:

A diagnosis of IgAV in childhood associates with increased risk and rate of subsequent hospital admission, ED attendance and severe comorbidity. The occurrence of childhood IgAV thus signifies the presence of a sustained predisposition to illness.

Acknowledgments:

Supported by an unrestricted grant from the Arthritis Foundation of Western Australia

Disclosure of Interests:

Johannes (“Hans”) Nossent Speakers bureau: Janssen, warren raymond: None declared, milica ognjenivic: None declared, Helen Keen Speakers bureau: Pfizer Austrlaia, Abbvie Australia, David Preen: None declared, Charles Inderjeeth Grant/research support from: UCB Australia, Speakers bureau: Eli Lilly

3'-Deoxy-3'-[18F]Fluorothymidine Uptake Is Related to Thymidine Phosphorylase Expression in Various Experimental Tumor Models

PURPOSE

We recently reported that high thymidine phosphorylase (TP) expression is accompanied by low tumor thymidine concentration and high 3'-deoxy-3'-[18F]fluorothymidine ([18F]FLT) uptake in four untreated lung cancer xenografts. Here, we investigated whether this relationship also holds true for a broader range of tumor models.

PROCEDURES

Lysates from n = 15 different tumor models originating from n = 6 institutions were tested for TP and thymidylate synthase (TS) expression using western blots. Results were correlated to [18F]FLT accumulation in the tumors as determined by positron emission tomography (PET) measurements in the different institutions and to previously published thymidine concentrations.

RESULTS

Expression of TP correlated positively with [18F]FLT SUVmax (ρ = 0.549, P < 0.05). Furthermore, tumors with high TP levels possessed lower levels of thymidine (ρ = - 0.939, P < 0.001).

CONCLUSIONS

In a broad range of tumors, [18F]FLT uptake as measured by PET is substantially influenced by TP expression and tumor thymidine concentrations. These data strengthen the role of TP as factor confounding [18F]FLT uptake.

Correction to: The relationship between endogenous thymidine concentrations and [18F]FLT uptake in a range of preclinical tumour models

CORRECTION

Unfortunately, the original version of Figs. 4, 5 and 6b in the article [1] contained errors in the n numbers as indicated on the columns. Please note that column heights and error bars in the original figures and data in the ESM tables are correct and statistical tests are valid. These corrections do not affect any results or conclusions in this article.

Prevalence and associations of gout and hyperuricaemia: results from an Australian population-based study

BACKGROUND

Despite gout and hyperuricaemia being major comorbid health issues worldwide, there is a knowledge gap regarding their impact in the Australian community.

AIMS

To determine the prevalence and associations of self-reported medically diagnosed gout and hyperuricaemia in an Australian population-based cohort.

METHODS

The North West Adelaide Health Study is a longitudinal cohort study consisting of three stages of data collection. Each stage comprised a self-complete questionnaire, clinic assessment and computer-assisted telephone interview. In Stage 3 (2008-2010), participants were asked if a doctor had ever diagnosed them with gout. Additional data included demographics, comorbidities, laboratory data and Short Form 36 (SF-36). Participants were defined as having gout if they had self-reported medically diagnosed gout or were taking any gout-specific medication (allopurinol, colchicine, probenecid). Hyperuricaemia was defined as a serum uric acid (SUA) level >0.42 mmol/L in men and >0.34 mmol/L in women.

RESULTS

The overall prevalence of gout was 5.2%. Males were significantly more likely to have gout than females (8.5 vs 2.1%, P < 0.001). The overall prevalence of hyperuricaemia was 16.6%, with being male again identified as a significant risk factor (17.8 vs 15.4%, P < 0.01). Both gout and hyperuricaemia were associated with male sex, body mass index and renal disease after multivariable adjustment. There was no significant difference reported in quality of life (mean SF-36) scores in participants with gout compared to unaffected individuals.

CONCLUSION

The prevalence of gout and hyperuricaemia is high in the South Australian population. This study emphasises the need for optimal diagnosis and management of gout in Australia.

The relationship between endogenous thymidine concentrations and [(18)F]FLT uptake in a range of preclinical tumour models

BACKGROUND

Recent studies have shown that 3'-deoxy-3'-[(18)F] fluorothymidine ([(18)F]FLT)) uptake depends on endogenous tumour thymidine concentration. The purpose of this study was to investigate tumour thymidine concentrations and whether they correlated with [(18)F]FLT uptake across a broad spectrum of murine cancer models. A modified liquid chromatography-mass spectrometry (LC-MS/MS) method was used to determine endogenous thymidine concentrations in plasma and tissues of tumour-bearing and non-tumour bearing mice and rats. Thymidine concentrations were determined in 22 tumour models, including xenografts, syngeneic and spontaneous tumours, from six research centres, and a subset was compared for [(18)F]FLT uptake, described by the maximum and mean tumour-to-liver uptake ratio (TTL) and SUV.

RESULTS

The LC-MS/MS method used to measure thymidine in plasma and tissue was modified to improve sensitivity and reproducibility. Thymidine concentrations determined in the plasma of 7 murine strains and one rat strain were between 0.61 ± 0.12 μM and 2.04 ± 0.64 μM, while the concentrations in 22 tumour models ranged from 0.54 ± 0.17 μM to 20.65 ± 3.65 μM. TTL at 60 min after [(18)F]FLT injection, determined in 14 of the 22 tumour models, ranged from 1.07 ± 0.16 to 5.22 ± 0.83 for the maximum and 0.67 ± 0.17 to 2.10 ± 0.18 for the mean uptake. TTL did not correlate with tumour thymidine concentrations.

CONCLUSIONS

Endogenous tumour thymidine concentrations alone are not predictive of [(18)F]FLT uptake in murine cancer models.

The concomitants of raised blood sugar: studies in newly-detected hyperglycaemics: II. Urinary albumin excretion, blood pressure and their relation to blood sugar levels

The albumin excretion rate following an oral glucose load was measured, using a sensitive radio-immunoassay method, in three groups drawn from the population of Bedford. The three groups – normal,borderline diabetic and diabetic – were classified by the level of the blood sugar 2 hours after the 50 -g glucose load. The degree of albumin excretion was positively correlated with the 2-hour blood sugar level, suggesting that hyperglycaemia may cause renal functional abnormality, which may be present at or before the time of diagnosis. In the diabetic group, only, the degree of albumin excretion was also positively correlated with the height of the blood pressure.

Abstract 1030: Use of 18F-FDG-PET as a biomarker to demonstrate activity of the novel AKT inhibitor AZD5363 in a xenograft model

Introduction: The PI3K/Akt/PTEN network is the most frequently de-regulated pathway in human cancer. The protein kinase Akt, a key node on this pathway, has been shown to drive proliferation and survival of tumour cells, and also plays a key role in glucose metabolism. Therefore, it is hypothesized that Akt inhibition can be assessed using 18F-flurodeoxyglucose (18F-FDG) positron emission tomography (PET).

The aim of this study was to determine tumour uptake of 18F-FDG 4 hours after an acute dose of AZD5363 or vehicle using a range of doses in the U87-MG xenograft model, the overall goal being to correlate 18F-FDG changes with tumour pharmacodynamics in the absence of any systemic glucose changes.

Materials & Methods: AZD5363 was administered orally at 75, 130, 200 and 300mg/kg. Prior to dosing blood glucose concentration was measured and mice were dosed with either vehicle or AZD5363 4 hours prior to imaging. 18F-FDG was administered as an i.v. bolus under anaesthesia; followed by a 45-minute wash-out period and a 20 minute PET scan. Mice were then sacrificed and blood samples taken for pharmacokinetic (PK) analysis and blood glucose concentration. Tumours were removed and snap frozen for pharmacodynamic analysis and background tissues taken for biodistribution analysis. Image analysis was carried out using Inveon Reconstruction Workplace (IRW) software. Biodistribution data were derived from gamma counting. Decay correction and uptake values were calculated using Microsoft Excel and statistical analysis performed using Graph Pad Prism.

Results: Mean tumour volumes were not statistically different amongst the five groups. There was significantly decreased 18F-FDG uptake (p&lt;0.05) in the tumour in all of the AZD5363 treated groups as a group average compared to vehicle; maxSUV = 4.06 ± 0.41 (SEM) in the vehicle; 3.42 ± 0.23; 3.16 ± 0.16; 3.12 ± 0.18 and 2.66 ± 0.06 (SEM) in the 75, 130, 200 and 300mg/kg groups respectively. There was a significant increase in blood glucose concentration at only the higher doses of 200 and 300mg/kg compared to the vehicle group post-dose (p&lt; 0.05). There was significantly increased 18F-FDG uptake in the blood, lung and liver from biodistribution data at the 300mg/kg treated dose compared to vehicle (p&lt;0.05). Ex-vivo tumour biomarker analyses demonstrated dose-dependent inhibition of PRAS40, GSK3β and S6 phosphorylation in response to AZD5363. Furthermore, AZD5363 resulted in dose-dependent inhibition of tumour growth in this xenograft model.

Conclusions: AZD5363 significantly reduced tumour 18F-FDG uptake at all four doses investigated in U87-MG human glioma xenografts 4 hours after drug administration. This correlated with inhibition of AKT substrate and downstream biomarker phosphorylation in the tumours and was seen at doses that did not cause systemic blood glucose changes. Therefore, 18F-FDG PET has potential as a biomarker for AZD5363 activity in the clinic.

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 1030. doi:10.1158/1538-7445.AM2011-1030

The insulin dilemma in resource-limited countries. A way forward?

The International Insulin Foundation (IIF) has developed and validated a needs-assessment instrument called the Rapid Assessment Protocol for Insulin Access (RAPIA) which has been used in seven countries in four continents to analyse the constraints to delivering effective continuing care for people with diabetes. One major contributor to the difficulties in availability of insulin is a failure to use the least costly sources and types of insulin and other effective drugs for diabetes. The purchase of insulins can consume as much as 10% of government expenditure on drugs, this being highly sensitive to the selection of newer analogue insulins as first-choice options, which cost between three and 13 times more than biosynthetic human insulin. Insulin cartridges for use with injection pens further add to costs. Similar considerations apply to most of the newer treatments for people with type 2 diabetes, which may cost up to 40 times more than metformin and sulfonylureas, still considered first-line drugs by European and US guidelines. Both biosynthetic human insulin and the first-line oral hypoglycaemic drugs are available from generic manufacturers. With the present price differentials, there is thus a growing need for countries involved in tendering for sourcing insulin to be provided with the guarantees of Good Manufacturing Practice, quality and bioequivalence, which would come from a WHO Pre-Qualification Scheme as currently exists for a variety of drugs for chronic diseases, both communicable and non-communicable. The IIF has developed a position statement on the provision and choice of diabetes treatments in resource-limited settings which should be applicable wherever consideration of resources is a component of therapeutic decision making.

Abstract A225: The mTOR kinase inhibitor AZD8055 modulates 18F-FDG uptake in vivo in the human glioma xenograft model U87-MG

Introduction: mTOR is a a sensor of mitogen, energy and nutrient levels and a central controller of cell growth. mTOR is present in two multi-protein complexes: mTORC1, rapamycin sensitive and containing raptor, and mTORC2, rapamycin-insensitive. AZD8055 is a small molecule ATP competitive inhibitor of mTOR kinase, thus inhibiting both mTORC1 and mTORC2. This results in a greater reduction of mTORC1 substrates pS6 on Ser235/236 and p4EBP1 on T37/46 compared to rapamycin. AZD8055 also reduces the mTORC2 substrate pAKT on Ser473. The PI3K-AKT-mTOR pathway is involved in glucose uptake/metabolism. 18F-Flurodeoxyglucose (18F-FDG) is a biomarker for glucose metabolism detectable by positron emission tomography (PET). It is used in clinical oncology for tumor diagnosis and is currently under evaluation for therapy monitoring. The aim of this study was to assess the impact of a single and 4 daily dosing of AZD8055 on 18F-FDG uptake in U87-MG human glioma xenografts implanted subcutaneously in nude mice.

Methods: AZD8055 was administered orally at a dose of 20 mg/kg qd for 1 or 4 days. Animals received either vehicle or AZD8055 1 hour prior to imaging. Mice were anaesthetised and then injected with approximately 15 MBq 18F-FDG i.v. via the tail vein. Forty-five minutes later, mice underwent PET scanning (20 minute scan, 3D histogramming and OSEM2D reconstruction) followed by biodistribution analysis. Image analysis was carried out using Inveon Research Workplace (IRW) software. Biodistribution data were derived from gamma counting.

Results: Plasma drug concentrations were not modified significantly by anesthesia and the imaging procedure. In the vehicle and AZD8055-treated groups, tumor volumes were comparable after single dose, but differed significantly following 4 days of treatment due to drug effect. Image analysis of 18F-FDG uptake after single and multiple doses showed that there was a significant difference (p&lt;0.05) in meanSUV, maxSUV and the percentage of injected dose per gram of tissue (%ID/g) between vehicle and drug treated tumors. Biodistribution analysis showed that the average 18F-FDG %ID/g in vehicle-treated tumors was significantly higher than in AZD8055-treated tumors (p&lt;0.05).

The changes in glucose uptake after 1 and 4 administrations were consistent with the pharmacodynamic effects of AZD8055 on pS6 and pAKT biomarkers in U87-MG tumors collected at the same time-points.

Conclusions: AZD8055 reduces significantly 18F-FDG uptake in U87-MG human glioma xenografts, as early as 1 hour after a single dose. This data suggests that 18F-FDG uptake could be used as an early sign of metabolic response to AZD8055.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A225.

Functional comparison of annexin V analogues labeled indirectly and directly with iodine-124

We are interested in imaging cell death in vivo using annexin V radiolabeled with (124)I. In this study, [(124)I]4IB-annexin V and [(124)I]4IB-ovalbumin were made using [(124)I]N-hydroxysuccinimidyl-4-iodobenzoate prepared by iododestannylation of N-hydroxysuccinimidyl-4-(tributylstannyl)benzoate. [(124)I]4IB-annexin V binds to phosphatidylserine-coated microtiter plates and apoptotic Jurkat cells and accumulates in hepatic apoptotic lesions in mice treated with anti-Fas antibody, while [(124)I]4IB-ovalbumin does not. In comparison with (124)I-annexin V, [(124)I]4IB-annexin V has a higher rate of binding to phosphatidylserine in vitro, a higher kidney and urine uptake, a lower thyroid and stomach content uptake, greater plasma stability and a lower rate of plasma clearance. Binding of radioactivity to apoptotic cells relative to normal cells in vitro and in vivo appears to be lower for [(124)I]4IB-annexin V than for (124)I-annexin V.

MBP-annexin V radiolabeled directly with iodine-124 can be used to image apoptosis in vivo using PET

A noninvasive method of measuring programmed cell death in the tumors of cancer patients using positron-emission tomography (PET) would provide valuable information regarding their response to therapeutic intervention. Our strategy is to radiolabel annexin V, a protein that binds to phosphatidylserine moieties that are translocated to the external leaflet of plasma membranes during apoptosis. We developed a phosphatidylserine-ELISA capable of distinguishing wild type from point mutant annexin V that is known to have a lower phosphatidylserine binding affinity. A maltose-binding protein/annexin V chimera was synthesized and purified with high yield using amylose resin. We showed that it bound to phosphatidylserine in the ELISA as well as to that exposed on apoptotic Jurkat cells; therefore, it was used in the development of a method for radiolabeling annexin V using iodine radionuclides. MBP-annexin V retained its phosphatidylserine binding properties on direct iodination, but at high levels of oxidizing agents (iodogen and chloramine T), its specificity for phosphatidylserine was compromised. (124)I-MBP-annexin V was successfully used to image Fas-mediated hepatic cell death in BDF-1 mice using PET. In conclusion, we have shown that MBP-annexin V and the phosphatidylserine ELISA are useful tools for the development of methods for radiolabeling annexin V for PET imaging.

Cancer incidence and mortality in patients with insulin-treated diabetes: a UK cohort study

Raised risks of several cancers have been found in patients with type II diabetes, but there are few data on cancer risk in type I diabetes. We conducted a cohort study of 28 900 UK patients with insulin-treated diabetes followed for 520 517 person-years, and compared their cancer incidence and mortality with national expectations. To analyse by diabetes type, we examined risks separately in 23 834 patients diagnosed with diabetes under the age of 30 years, who will almost all have had type I diabetes, and 5066 patients diagnosed at ages 30–49 years, who probably mainly had type II. Relative risks of cancer overall were close to unity, but ovarian cancer risk was highly significantly raised in patients with diabetes diagnosed under age 30 years (standardised incidence ratio (SIR)=2.14; 95% confidence interval (CI) 1.22–3.48; standardised mortality ratio (SMR)=2.90; 95% CI 1.45–5.19), with greatest risks for those with diabetes diagnosed at ages 10–19 years. Risks of cancer at other major sites were not substantially raised for type I patients. The excesses of obesity- and alcohol-related cancers in type II diabetes may be due to confounding rather than diabetes per se.