Adaption and validation of the Rwandese version of the Mood Disorder Questionnaire for the screening of bipolar disorder

BACKGROUND

Bipolar disorder is challenging to diagnose. In Rwanda, a sub-Saharan country with a limited number of psychiatrists, the number of people with an undetected diagnosis of bipolar disorder could be high. Still, no screening tool for the disorder is available in the country. This study aimed to adapt and validate the Mood Disorder Questionnaire in the Rwandan population.

METHODS

The Mood Disorder Questionnaire was translated into Kinyarwanda. The process involved back-translation, cross-cultural adaptation, field testing of the pre-final version, and final adjustments. A total of 331 patients with either bipolar disorder or unipolar major depression from two psychiatric outpatient hospitals were included. The statistical analysis included reliability and validity analyses and receiver operating characteristic curve (ROC) analysis. The optimal cut-off was chosen by maximizing Younden's index.

RESULTS

The Rwandese version of The Mood Disorder Questionnaire had adequate internal consistency (Cronbach's alpha =0.91). The optimal threshold value was at least six positive items, which yielded excellent sensitivity (94.7%), and specificity (97.3%). The ROC area under the curve (AUC) was 0.99.

CONCLUSION

The adapted tool showed good psychometric properties in terms of reliability and validity for the screening of bipolar disorder, with a recommended cutoff value of six items on the symptom checklist for a positive score and an exclusion of items 14 and 15. The tool has the potential to be a crucial instrument to identify otherwise undetected cases of bipolar disorder in Rwanda, improving access to mental health treatment, thus enhancing the living conditions of people with bipolar disorder.

Group psychoeducation for persons with bipolar disorder in Rwanda: a study protocol for a randomized controlled trial

BACKGROUND

The efficacy of psychoeducation as an add-on treatment to pharmacotherapy is well documented in treating symptoms and in relapse prevention for persons with bipolar disorder in western countries. Yet, no studies on psychosocial interventions for persons with bipolar disorder have been conducted in a low-income country in Africa.

AIM

To develop a bipolar group psychoeducation program contextualized to the Rwandese setting, and determine its effect on symptom severity, medical adherence, and internalized stigma.

METHODS

A culturally adapted guide manual was developed by local mental health professionals, including nurses, psychologists, and medical doctors. In-depth interviews with participants were held prior to and will be held following the intervention to address the cultural aspect of living with bipolar disease and the impact of the program. A two-armed randomized controlled trial has been set up at the tertiary mental health hospitals in Rwanda, with an intervention and a waiting list arm. A sample size of at least 50 in each arm was calculated as a requirement. The study's primary outcome measure will be the difference in relapse rate measured on the Young Mania Rating Scale and Hamilton Depression Scale-17. Differences in mean change on scales for medical adherence and internalized stigma will be secondary outcomes. Data will be analyzed according to the intention-to-treat principle. Participants will be assessed subsequently at baseline, at the end of the intervention period, and three months and 12 months post-intervention.

DISCUSSION

This study will be one of the first intervention trials on bipolar disorder in a low-income country. If proven successful in reducing morbidity and increasing the quality of life in persons with bipolar disorder, it is anticipated that the psychoeducation program can be implemented at the district and community level and act as inspiration for other low-resource settings.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04671225. Registered on November 2020.

Stress management versus cognitive restructuring: A randomized clinical study on traumatized refugees

Background and aim

There is a lack of evidence regarding which kind of psychotherapy that is the most effective when treating traumatized refugees. Studies on the effect of psychotherapy among other patient groups with PTSD suggest a good effect using cognitive behavioural therapy (CBT). The competence center for transcultural psychiatry (CTP) has specialized in the treatment of traumatized refugees. The objectives were to study the effect of CBT with a focus on either stress management or cognitive restructuring in a clinical sample of traumatized refugees with PTSD and to identify predictors for the treatment effect.

Methods

All patients (n = 143) referred to CTP from June 2011–March 2012 and fulfilling the inclusion criteria were offered to participate in the study. Participants were offered combined treatment with a psychiatrist (psycho-education and psychopharmacological treatment when needed) and a psychologist (CBT). The duration of the treatment was 6–7 months. The participants were randomized to either CBT with a focus on stress management or cbt with focus on cognitive restructuring. The primary outcome was PTSD measured by the Harvard Trauma Questionnaire.

Results

The results are presently being analyzed and will be presented at the congress.

Conclusions

Both research results and the clinical experience at CTP suggest, that cognitive restructuring is not always a useful tool and that stress reducing techniques could be more useful. This hypothesis was tested in the present study.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Analysis of radiation effects in two irradiated tumor spheroid models

Multicellular spheroids have proven suitable as three-dimensional in vivo-like models of non-vascularized micrometastases. Unlike monolayer-based models, spheroids mirror the cellular milieu and the pathophysiological gradients inside tumor nodules. However, there is limited knowledge of the radiation effects at the molecular level in spheroids of human origin. The present study is a presentation of selected cell biological processes that may easily be analyzed with methods available at routine pathology laboratories. Using gamma irradiated pancreatic neuroendocrine BON1 and colonic adenocarcinoma HCT116 spheroids as model systems, the present study assessed the radiobiological response in these models. Spheroid growth after irradiation was followed over time and molecular responses were subsequently assessed with immunohistochemistry (IHC) staining for descriptive analyses and semi-automatic grading of apoptosis, G₂-phase and senescence in thin sections of the spheroids. Growth studies demonstrated the BON1 spheroids were slower growing and less sensitive to radiation compared with the HCT116 spheroids. IHC staining for G₂-phase was primarily observed in the outer viable P-cell layers of the spheroids, with the 6 Gy irradiated HCT116 spheroids demonstrating a very clear increase in staining intensity compared with unirradiated spheroids. Apoptosis staining results indicated increased apoptosis with increasing radiation doses. No clear association between senescence and radiation exposure in the spheroids were observed. The present results demonstrate the feasibility of the use of multicellular spheroids of human origin in combination with IHC analyses to unravel radiobiological responses at a molecular level. The present findings inspire further investigations, including other relevant IHC-detectable molecular processes in time- and radiation dose-dependent settings.

Intra-image referencing for simplified assessment of HER2-expression in breast cancer metastases using the Affibody molecule ABY-025 with PET and SPECT

PURPOSE

In phase I/II-studies radiolabelled ABY-025 Affibody molecules identified human epidermal growth factor receptor 2 (HER2) expression in breast cancer metastases using PET and SPECT imaging. Here, we wanted to investigate the utility of a simple intra-image normalization using tumour-to-reference tissue-ratio (T/R) as a HER2 status discrimination strategy to overcome potential issues related to cross-calibration of scanning devices.

METHODS

Twenty-three women with pre-diagnosed HER2-positive/negative metastasized breast cancer were scanned with [¹¹¹In]-ABY-025 SPECT/CT (n = 7) or [⁶⁸Ga]-ABY-025 PET/CT (n = 16). Uptake was measured in all metastases and in normal spleen, lung, liver, muscle, and blood pool. Normal tissue uptake variation and T/R-ratios were established for various time points and for two different doses of injected peptide from a total of 94 whole-body image acquisitions. Immunohistochemistry (IHC) was used to verify HER2 expression in 28 biopsied metastases. T/R-ratios were compared to IHC findings to establish the best reference tissue for each modality and each imaging time-point. The impact of shed HER2 in serum was investigated.

RESULTS

Spleen was the best reference tissue across modalities, followed by blood pool and lung. Spleen-T/R was highly correlated to PET SUV in metastases after 2 h (r = 0.96, P < 0.001) and reached an accuracy of 100% for discriminating IHC HER2-positive and negative metastases at 4 h (PET) and 24 h (SPECT) after injection. In a single case, shed HER2 resulted in intense tracer retention in blood. In the remaining patients shed HER2 was elevated, but without significant impact on ABY-025 biodistribution.

CONCLUSION

T/R-ratios using spleen as reference tissue accurately quantify HER2 expression with radiolabelled ABY-025 imaging in breast cancer metastases with SPECT and PET. Tracer binding to shed HER2 in serum might affect quantification in the extreme case.

Chronic Tension-Type Headache Treated with Acupuncture, Physical Training and Relaxation Training. Between-Group Differences

The aim of this study was to compare acupuncture, relaxation training and physical training in the treatment of chronic tension-type headache (CTTH). The study comprised 90 consecutive patients with CTTH who were randomly allocated to acupuncture, relaxation training or physical training. Headache intensity, headache-free days and headache-free periods were registered using a visual analogue scale and a headache diary. The measurements were made 4 weeks before, immediately after, and 3 and 6 months after the treatment period. Immediately after the last treatment, the number of headache-free periods and of headache-free days was higher in the relaxation group compared with the acupuncture group. There were no other significant differences between the groups at any time point. The clinical implications of our findings are that relaxation training induced the most pronounced effects directly after the treatment period, compared with acupuncture and physical training.

Good manufacturing practice production of [(68)Ga]Ga-ABY-025 for HER2 specific breast cancer imaging

Therapies targeting human epidermal growth factor receptor type 2 (HER2) have revolutionized breast cancer treatment, but require invasive biopsies and rigorous histopathology for optimal patient stratification. A non-invasive and quantitative diagnostic method such as positron emission tomography (PET) for the pre-therapeutic determination of the presence and density of the HER2 would significantly improve patient management efficacy and treatment cost. The essential part of the PET methodology is the production of the radiopharmaceutical in compliance with good manufacturing practice (GMP). The use of generator produced positron emitting (68)Ga radionuclide would provide worldwide accessibility of the agent. GMP compliant, reliable and highly reproducible production of [(68)Ga]Ga-ABY-025 with control over the product peptide concentration and amount of radioactivity was accomplished within one hour. Two radiopharmaceuticals were developed differing in the total peptide content and were validated independently. The specific radioactivity could be kept similar throughout the study, and it was 6-fold higher for the low peptide content radiopharmaceutical. Intrapatient comparison of the two peptide doses allowed imaging optimization. The high peptide content decreased the uptake in healthy tissue, in particular liver, improving image contrast. The later imaging time points enhanced the contrast. The combination of high peptide content radiopharmaceutical and whole-body imaging at 2 hours post injection appeared to be optimal for routine clinical use.

The treatment of traumatised refugees with sertraline versus venlafaxine in combination with psychotherapy – a randomised clinical study

Background and aim

Today we lack sufficient evidence to conclude which type of treatment approach that is most efficient when it comes to trauma-affected refugees. That is a problem for both patients and doctors as well as for society. Also there is a lack of studies, which examine the relation between psychosocial resources and treatment efficiency, in order to find reliable predictors of treatment outcome. This study therefore aims to produce new evidence within this field in order to optimise treatment for trauma-affected refugees with complex PTSD.

Methods

The study included 207 patients referred to Competence Centre for Transcultural Psychiatry between April 2012 and September 2013. Patients were randomised into one of the two treatment groups: a sertraline group (n = 109) or a venlafaxine group (n = 98). Patients in both groups received the same manual based cognitive behavioural therapy, specially adapted to this group of patients. The trial endpoints were PTSD-and depression symptoms and social functioning, all measured on validated ratings scales. Furthermore the study examined the relation between expected outcome of treatment from a range of predictors and the relation to the treatment results for the individual patient.

Results

Data are presently being analysed and results will be ready for the conference.

Conclusion

The study is among the largest randomised studies ever conducted on pharmacological treatment among traumatised refugees. It is expected to bring forward new knowledge about clinical evaluation and medical treatment of traumatised refugees.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Measuring HER2-Receptor Expression In Metastatic Breast Cancer Using [68Ga]ABY-025 Affibody PET/CT

Purpose: Positron Emission Tomography (PET) imaging of HER2 expression could potentially be used to select patients for HER2-targed therapy, predict response based on uptake and be used for monitoring. In this phase I/II study the HER2-binding Affibody molecule ABY-025 was labeled with ⁶⁸Ga-gallium ([⁶⁸Ga]ABY-025) for PET to study effect of peptide mass, test-retest variability and correlation of quantified uptake in tumors to histopathology.

Experimental design: Sixteen women with known metastatic breast cancer and on-going treatment were included and underwent FDG PET/CT to identify viable metastases. After iv injection of 212±46 MBq [⁶⁸Ga]ABY-025 whole-body PET was performed at 1, 2 and 4 h. In the first 10 patients (6 with HER2-positive and 4 with HER2-negative primary tumors), [⁶⁸Ga]ABY-025 PET/CT with two different doses of injected peptide was performed one week apart. In the last six patients (5 HER2-positive and 1 HER2-negative primary tumors), repeated [⁶⁸Ga]ABY-025 PET were performed one week apart as a test-retest of uptake in individual lesions. Biopsies from 16 metastases in 12 patients were collected for verification of HER2 expression by immunohistochemistry and in-situ hybridization.

Results: Imaging 4h after injection with high peptide content discriminated HER2-positive metastases best (p<0.01). PET SUV correlated with biopsy HER2-scores (r=0.91, p<0.001). Uptake was five times higher in HER2-positive than in HER2-negative lesions with no overlap (p=0.005). The test-retest intra-class correlation was r=0.996. [⁶⁸Ga]ABY-025 PET correctly identified conversion and mixed expression of HER2 and targeted treatment was changed in 3 of the 16 patients.

Conclusion: [⁶⁸Ga]ABY-025 PET accurately quantifies whole-body HER2-receptor status in metastatic breast cancer.

An eDNA assay for Irish Petromyzon marinus and Salmo trutta and field validation in running water

This pilot study presents an environmental DNA (eDNA) assay for sea lamprey Petromyzon marinus and brown trout Salmo trutta, two species of economic and conservation importance in the Republic of Ireland. The results demonstrate the effectiveness of eDNA for assessing presence of low-abundance taxa (here, P. marinus) for environmental managers, and they highlight the potential for assessing relative abundance of rare or invasive freshwater species.

Influence of grazing management on claw disorders in Swedish freestall dairies with mandatory grazing

Our hypothesis was that grazing time, the number of days (duration) and number of hours per day, affected claw health. From Swedish freestall herds that fulfilled our criteria of claw-trimming routines, 201 herds were randomly selected for a telephone interview regarding grazing management. Herd data were retrieved from the Swedish Official Milk Recording Scheme. Claw disorders to be analyzed were recorded at maintenance claw trimming before and after the grazing period and included mild and severe dermatitis, severe heel-horn erosion, and sole ulcer (including severe sole hemorrhage). Any remark included one or more of these recorded disorders. The odds for having a recorded claw disorder at the autumn trimming in relation to grazing management, as well as to herd- and cow-related parameters, was tested using multilevel logistic regression models. The final statistical analysis included 17,600 cows in 174 herds, which were distributed from the south to the north of Sweden with decreasing length of mandatory grazing period because of climate. Grazing duration was statistically associated with the risk of sole ulcer, but it was not linear. However, grazing duration was not statistically associated with the odds for any remark, dermatitis, or heel-horn erosion. The odds for dermatitis were lower with access to pasture for 24 h compared with either day or night access. Otherwise, the number of hours that the animals had access to grazing per day was not significantly associated with any of the other analyzed claw disorders. Higher pasture stocking density (number of cow hours per day per hectare) was associated with a higher odds for dermatitis and sole ulcer. For all recorded claw disorders, the highest odds for having a disorder after the grazing period were consistently when the cow had the same claw disorder before the release to pasture. The positive effects of grazing on claw health were less than expected, and the previous known effects of breed, days in milk, parity, production system, housing environment, and management were verified for most claw disorders. If cows in today's loose housing systems have a more restrictive grazing than cows in tie-stall herds previously experienced, one cannot expect as strong an effect even if grazing is mandatory in all Swedish dairy cattle. Despite some positive effects of grazing, good stall environment and management during the housing period seem to be more important to obtain good claw health.

Isolation and characterization of 13 polymorphic microsatellite loci in Hypostomus ancistroides (Teleostei, Loricariidae) and cross-amplification in related species

This study details 13 novel polymorphic microsatellite loci in the armoured catfish Hypostomus ancistroides, and assesses their utility for population genetic studies. The analysis of 30 individuals revealed a total of 99 different alleles (ranging from two to 15 alleles per locus), with an average of 7·62 alleles per locus, with observed and expected heterozygosities ranging from 0·103 to 0·931 and from 0·102 to 0·906, respectively. One of the 13 loci showed significant deviations from Hardy-Weinberg equilibrium, probably due to the presence of null alleles, inferred from the excess of homozygotes.

Discovery of trace amine-associated receptor 1 ligands by molecular docking screening against a homology model

An in silico screen of a TAAR1 homology model identifies novel ligands.

First-in-human molecular imaging of HER2 expression in breast cancer metastases using the 111In-ABY-025 affibody molecule

The expression status of human epidermal growth factor receptor type 2 (HER2) predicts the response of HER2-targeted therapy in breast cancer. ABY-025 is a small reengineered Affibody molecule targeting a unique epitope of the HER2 receptor, not occupied by current therapeutic agents. This study evaluated the distribution, safety, dosimetry, and efficacy of (111)In-ABY-025 for determining the HER2 status in metastatic breast cancer.

METHODS

Seven patients with metastatic breast cancer and HER2-positive (n = 5) or -negative (n = 2) primary tumors received an intravenous injection of approximately 100 μg (∼ 140 MBq) of (111)In-ABY-025. Planar γ-camera imaging was performed after 30 min, followed by SPECT/CT after 4, 24, and 48 h. Blood levels of radioactivity, antibodies, shed serum HER2, and toxicity markers were evaluated. Lesional HER2 status was verified by biopsies. The metastases were located by (18)F-FDG PET/CT 5 d before (111)In-ABY-025 imaging.

RESULTS

Injection of (111)In-ABY-025 yielded a mean effective dose of 0.15 mSv/MBq and was safe, well tolerated, and without drug-related adverse events. Fast blood clearance allowed high-contrast HER2 images within 4-24 h. No anti-ABY-025 antibodies were observed. When metastatic uptake at 24 h was normalized to uptake at 4 h, the ratio increased in HER2-positive metastases and decreased in negative ones (P < 0.05), with no overlap and confirmation by biopsies. In 1 patient, with HER2-positive primary tumor, (111)In-ABY-025 imaging correctly suggested a HER2-negative status of the metastases. The highest normal-tissue uptake was in the kidneys, followed by the liver and spleen.

CONCLUSION

(111)In-ABY-025 appears safe for use in humans and is a promising noninvasive tool for discriminating HER2 status in metastatic breast cancer, regardless of ongoing HER2-targeted antibody treatment.

Abstract P4-01-17: Molecular imaging and quantification of HER-2 status in metastatic breast cancer by using 68Ga-ABY-025/PET-CT

Background: Molecular imaging, in particular, positron emission tomography (PET) provides unique possibility to non-invasively quantify the biomarkers. A small peptide, ABY-025, is targeting a unique epitope of the HER2-receptor and can be labeled with 111In or 68Ga. It is non-competitive with current antibody-targeted epitopes and is approximately 25 times smaller than an antibody and posses superior pharmacokinetics as imaging agent. We have earlier reported promising results of lesion visualization and determination of HER2 status by 111In-ABY-025/SPECT-CT in seven patients with metastatic breast cancer (MBC). As PET-CT provides superior possibilities for quantification and allows for imaging with shorter time frames, we now investigate 68Ga-ABY-025 in HER2-positive and HER2-negative MBC patients in a prospective study. The influence of the administered amount of ABY-025 on the discrimination between HER2-positive and HER2-negative metastases as well as detection rate and image contrast is investigated. The HER2 status changes will be followed at disease progression. We report here promising data on the first three patients.

Patients and methods: The study considers twenty patients in two cohorts. Of the first 10 patients, 4 should have HER2-negative MBC and 6 patients HER2-positive disease. Metastases were localized by 18F-FDG/PET-CT prior HER2 imaging. Each patient (two HER2-positive and one HER-negative) underwent two subsequent examinations. First, 68Ga-ABY-025 PET/CT (ABY-025: 75±14 μg) was performed with dynamic acquisition during 0-45 minutes and static images after 1, 2 and 4 hours. The procedure was repeated after one week with a higher dose of 68Ga-ABY-025 (ABY-025: 445±10 μg) to identify the optimal dosage for the discrimination between HER2-positive and HER2-negative metastases. Blood levels of radioactivity, anti-ABY-025-antibodies, shed serum HER2 and toxicity markers were evaluated. Biopsies were taken to verify the HER2 status of the lesions. The second cohort of 10 patients (all with HER2-positive disease), will have their primary PET-CT with the optimal dose of 68Ga-ABY-025 and will, as the HER-positive from the first cohort, have a follow-up 68Ga-ABY-025 PET/CT after disease progression or, at latest, after 9 months.

Results: The imaging agent was well tolerated by the patients without adverse events. The rapid blood clearance and normal tissue wash out allowed high contrast HER2 images within a few hours. The HER2 status was confirmed by histological analysis of biopsies. In one patient with HER2-negative primary tumor, imaging suggested a HER2-positive liver metastasis. The change of HER2 expression was verified with analysis of the corresponding biopsy. This finding resulted in the change of the treatment management. Preliminary validation suggests the preference of high dose ABY-025 in terms of image contrast and detection. The study is ongoing and more patients will be reported

Conclusion: Preliminary results indicate strong potential of 68Ga-ABY-025 PET/CT for discriminating HER2-positive versus HER2-negative metastatic breast cancer, regardless of ongoing HER2-targeted antibody treatment. The method introduces rapid whole-body receptor mapping of primary tumor and metastases in a single examination.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-01-17.

Rapid, economical single-nucleotide polymorphism and microsatellite discovery based on de novo assembly of a reduced representation genome in a non-model organism: a case study of Atlantic cod Gadus morhua

By combining next-generation sequencing technology (454) and reduced representation library (RRL) construction, the rapid and economical isolation of over 25 000 potential single-nucleotide polymorphisms (SNP) and >6000 putative microsatellite loci from c. 2% of the genome of the non-model teleost, Atlantic cod Gadus morhua from the Celtic Sea, south of Ireland, was demonstrated. A small-scale validation of markers indicated that 80% (11 of 14) of SNP loci and 40% (6 of 15) of the microsatellite loci could be amplified and showed variability. The results clearly show that small-scale next-generation sequencing of RRL genomes is an economical and rapid approach for simultaneous SNP and microsatellite discovery that is applicable to any species. The low cost and relatively small investment in time allows for positive exploitation of ascertainment bias to design markers applicable to specific populations and study questions.

Tendencies for higher co-expression of EGFR and HER2 and downregulation of HER3 in prostate cancer lymph node metastases compared with corresponding primary tumors

The epidermal growth factor receptor (EGFR) family members are potential targets for therapy using extra-cellular domain receptor binding agents, such as the antibodies trastuzumab and cetuximab, or antibodies labeled with therapeutically useful radionuclides or toxins. This is especially the case when the tumor cells are resistant to chemotherapy and tyrosine kinase inhibitors. Studies concerning the expression of these receptors in prostate cancer vary in the literature, possibly due to differences in patient inclusion, sample preparations and scoring criteria. In our study, EGFR, HER2 and HER3 expression was analyzed in prostate cancer samples from primary tumors and corresponding lymph node metastases from 12 patients. The expression of HER2 and EGFR was scored from immunohistochemical preparations and the HercepTest criteria (0, 1+, 2+ or 3+), while HER3 expression was scored as no, weak or strong staining. There were 5 EGFR-positive (2+ or 3+) primary tumors and 6 EGFR-positive lymph node metastases, and there was EGFR upregulation in one metastasis. Only 4 of the 12 patients had marked HER2 expression (2+ or 3+) in their primary tumors and there was one downregulation and 5 cases of upregulation in the metastases. Thus, a total of 8 out of 12 analyzed metastases were HER2-positive. Of the 12 primary tumors, 9 expressed HER3 while only 2 of the lymph node metastases expressed recognizable HER3 staining, so 7 metastases appeared to have downregulated HER3 expression. In one of the primary tumors there was positive co-expression of EGFR and HER2, while this co-expression was observed in 4 of the metastases. Thus, there were tendencies for upregulation of HER2, increased co-expression of EGFR and HER2 and downregulation of HER3 in the prostate cancer lymph node metastases in comparison to the primary tumors. The results are encouraging for studies involving more patients. Possible strategies for EGFR- and HER2-targeted therapy are briefly discussed in the present study, especially with regard to the expression and co-expression of EGFR and HER2 in metastases.

Changes in growth, po(2) and ph after exposure to oxamate - studies of 2 human tumor-cell lines growing as multicellular spheroids

The basic metabolism and pO(2) and pH gradients in spheroids were characterized and, in some cases, changed by the addition of the pyruvate analogue oxamate. Two human tumour spheroid types, colon adenocarcinoma HT29 and malignant glioma U118MG, were applied as models. Microelectrode measurements in HT29 spheroids showed steep pO(2) gradients with large differences between surface and center, Delta pO(2), and low central pO(2) values. The HT29 spheroids had rather flat pH gradients. The U118MG spheroids had less steep pO(2) gradients but steeper pH gradients. Determinations of 1-C-14 and 2-C-14 pyruvate oxidation rates, for characterization of the oxidative glucose breakdown as well as of lactate dehydrogenase kinetics, showed consistent results with the microelectrode measurements in that there was high oxidative metabolism in the HT29 spheroids whereas the U118MG spheroids relied more on glycolysis. Western blot investigations of the LDH isoenzyme composition showed different isoenzyme patterns in the two spheroid types with a lack of LDH1 in U118MG spheroids. Addition of 40 mM of oxamate gave decreased 1-C-14- and 2-C-14-pyruvate oxidation rates in the HT29 cells and inhibition of LDH activity in the U118MG cells. Oxamate increased the central pO(2) values in HT29 spheroids and the central pH values in U118MG spheroids. One example of experimental therapy was applied and oxamate acted as a radiation sensitizer in the U118MG system and as a radioprotective substance in the HT29 system. This has to be analysed in more detail.

Balancing selection on MHC class I in wild brown trout Salmo trutta

Evidence is reported for balancing selection acting on variation at major histocompatibility complex (MHC) in wild populations of brown trout Salmo trutta. First, variation at an MHC class I (satr-uba)-linked microsatellite locus (mhc1) is retained in small S. trutta populations isolated above waterfalls although variation is lost at neutral microsatellite markers. Second, populations across several catchments are less differentiated at mhc1 than at neutral markers, as predicted by theory. The population structure of these fish was also elucidated.

MHC-mediated spatial distribution in brown trout (Salmo trutta) fry

Major histocompatibility complex (MHC) class I-linked microsatellite data and parental assignment data for a group of wild brown trout (Salmo trutta L.) provide evidence of closer spatial aggregation among fry sharing greater numbers of MHC class I alleles under natural conditions. This result confirms predictions from laboratory experiments demonstrating a hierarchical preference for association of fry sharing MHC alleles. Full-siblings emerge from the same nest (redd), and a passive kin association pattern arising from limited dispersal from the nest (redd effect) would predict that all such pairs would have a similar distribution. However, this study demonstrates a strong, significant trend for reduced distance between pairs of full-sibling fry sharing more MHC class I alleles reflecting their closer aggregation (no alleles shared, 311.5 ± (s.e.)21.03 m; one allele shared, 222.2 ± 14.49 m; two alleles shared, 124.9 ± 23.88 m; P<0.0001). A significant trend for closer aggregation among fry sharing more MHC class I alleles was also observed in fry pairs, which were known to have different mothers and were otherwise unrelated (ML-r = 0) (no alleles: 457.6 ± 3.58 m; one allele (422.4 ± 3.86 m); two alleles (381.7 ± 10.72 m); P<0.0001). These pairs are expected to have emerged from different redds and a passive association would then be unlikely. These data suggest that sharing MHC class I alleles has a role in maintaining kin association among full-siblings after emergence. This study demonstrates a pattern consistent with MHC-mediated kin association in the wild for the first time.

Effects of affinity on binding of HER2-targeting Affibody molecules: model experiments in breast cancer spheroids

Binding of a targeting agent in tumor tissue is influenced by many factors such as molecular weight, charge and affinity of the targeting agent and vascularization of the tumor. In this study, we analyzed tumor cell binding of three HER2-specific and radiolabeled Affibody molecules with different affinities. The Affibody molecules had affinities in the range of 0.12-3.8 nM. Cellular binding was analyzed, after 2 h of incubation, in tumor spheroids composed of BT474 breast cancer cells, which highly express HER2. Binding was, due to the binding-site barrier, limited to the outer 15 ± 5 µm rim of the spheroids, independent of affinity when the concentration of the substances was low. When the concentration was high, the binding site barrier was overcome and the binding occurred approximately 35 ± 5 µm into the spheroids for the two high affinity substances and 50 ± 5 µm for the low affinity substance. The lower affinity might allow for penetration into deeper regions due to less firm binding. We conclude that there is a binding site barrier within tumor spheroids which can be overcome by increased concentration of substance and modified by affinity.

EGFR, HER2 and HER3 expression in primary colorectal carcinomas and corresponding metastases: Implications for targeted radionuclide therapy

Members of the epidermal growth factor receptor, EGFR, family are interesting as targets for radionuclide therapy using targeting agents labeled with α- or β-emitting radionuclides, especially when EGFR-positive colorectal carcinomas, CRC, are resistant to EGFR inhibiting agents like cetuximab and various tyrosine kinase inhibitors. The expression of EGFR, HER2 and HER3 was therefore analyzed in CRC samples from primary tumors, corresponding lymph node metastases and, in a few cases, liver metastases. The expression of HER2 and EGFR was scored from immunohistochemical preparations using the HercepTest criteria 0, 1+, 2+ or 3+ for cellular membrane staining while HER3 expression was scored as no, weak or strong cytoplasm staining. Material from 60 patients was analyzed. The number of EGFR 2+ or 3+ positive primary tumors was 16 out of 56 (29%) and for lymph node metastases 8 out of 56 (14%) whereas only one out of nine (11%) liver metastases were positive. Thus, there was lower EGFR positivity in the metastases. Only one among 53 patients was strongly HER2 positive and this in both the primary tumor and the metastasis. Eight out of 49 primary tumors (16%) were strongly HER3 positive and the corresponding numbers for lymph node metastases were 9 out of 49 (18%) and for liver metastases 2 out of 9 (22%). The observed number of strongly EGFR positive cases was somewhat low but EGFR might be, for the cases with high EGFR expression in metastases, a target for radionuclide therapy. HER2 seems not to be of such interest due to rare expression, neither HER3 due to mainly expression in the cytoplasm. The requirements for successful EGFR targeted radionuclide therapy are discussed, as well as patient inclusion criteria related to radionuclide therapy.

Effects of an EGFR-binding affibody molecule on intracellular signaling pathways

Effects on intracellular signaling were studied in cells treated with the affibody molecule (ZEGFR:955)2 that targets the epithelial growth factor receptor (EGFR). EGFR is overexpressed in many types of cancers and plays a fundamental role in cell signaling and it is of interest to find targeting agents capable of blocking the receptor. The clinically approved antibody cetuximab (Erbitux) and the natural ligand EGF were included as reference molecules. Two EGFR-rich cell lines, A-431 and U-343, were exposed to the three targeting agents and lysed. The cell lysates were immunoprecipitated with the receptors, or directly separated by SDS-Page. Autophosphorylation of the receptors and phosphorylation of the downstream signaling proteins Erk and Akt, were evaluated by Western blotting. Although the three different agents compete for the same binding site on EGFR, they influenced the signaling differently. The affibody molecule did not induce autophosphorylation of EGFR or any other receptor in the EGFR-family but, in spite of this, induced phosphorylation of Erk in both cell lines and Akt in the A-431 cells. Thus, the results suggest that the signaling pattern induced by (ZEGFR:955)2 is only partly similar to that induced by cetuximab. This makes the affibody molecule a potentially interesting alternative to cetuximab for EGFR-targeted therapy since it might give different therapy-related effects on tumor cells and different side effects on normal tissues.

Quantification of internalization of EGFR-binding Affibody molecules: Methodological aspects

Tumor cell internalization of targeting agents is of interest, since internalization influences the local retention time of a radionuclide and thereby imaging quality in PET and SPECT and effects of radionuclide therapy. In cases where nuclear methods are not applicable at the cellular level, quantitative fluorescent techniques are useful as described in this article. Two fluorescence-based methods to study cellular internalization were applied: the CypHer and the Alexa488-quenching methods, both utilized in fluorescence microscopy and flow cytometry. Two EGFR-binding Affibody molecules were analyzed in A431 cells: the monomer Z1907 and the dimer (Z1907)2. EGF, cetuximab and non-specific Affibody molecules were used as controls. For comparison, internalization of 111In-labeled Z1907 was studied with the acid wash internalization assay. The Cypher method is straightforward, but requires equal labeling of all compounds for accurate quantification. The Alexa488-quenching method is preferable since it is independent of the dye-to-protein ratio. According to this method, about 45% of EGF and 19-24% of the bound Affibody molecules and cetuximab were internalized within one hour. Similar results were seen with 111In-Z1907 in the acid wash method, while (Z1907)2 was not removed by acid and thus could not be studied this way. The fluorescence-based Alexa488-quenching method is well suited to quantitatively analyze internalization of targeting agents, also those that resist acid wash. The internalized fraction showed that both the monomeric and dimeric Affibody molecules are expected to give good uptake and thereby good retention of metallic radionuclides which will render good tumor to background values.

15-Lipoxygenase-2 is expressed in macrophages in human carotid plaques and regulated by hypoxia-inducible factor-1alpha

BACKGROUND

Macrophages are prominent in hypoxic areas of atherosclerotic lesions and their secreted cytokines, growth factors and activity of enzymes are involved in atherogenesis. Previously, we showed that 15-lipoxygenase (LOX)-2 is expressed in human monocyte-derived macrophages and that hypoxia increases 15-LOX-2 expression and secretion of pro-inflammatory molecules. Here we investigated whether human carotid plaque macrophages express 15-LOX-2 and whether its expression in macrophages is regulated by hypoxia through hypoxia-inducible factor 1alpha (HIF-1alpha).

MATERIALS AND METHODS

Carotid plaques from 47 patients with high-grade symptomatic carotid artery stenosis were analysed using immunohistochemistry, and stained areas were quantified by digital image analysis. Carotid plaque macrophages were isolated with anti-CD14 immunobeads using an immunomagnetic bead technique. Primary macrophages were transfected with HIF-1alpha siRNA or control siRNA before extraction of RNA and medium analysis.

RESULTS

In paired tissue sections, the extent of staining for CD68 correlated with staining for 15-LOX-2 but not for 15-LOX-1. In carotid plaque macrophages isolated with anti-CD14 immunobeads, 15-LOX-2 mRNA was expressed at high levels. In primary macrophages, 15-LOX-2 expression was significantly increased by incubation with the HIF-1alpha stabilizer dimethyloxalylglycine. Knockdown of HIF-1alpha significantly decreased production of the 15-LOX-2 enzyme products 12- and 15-hydroxyeicosatetraenoic acid. In carotid plaques, HIF-1alpha staining correlated with staining for 15-LOX-2.

CONCLUSIONS

These results demonstrate that 15-LOX-2 is highly expressed in human plaques and is correlated with the presence of macrophages and HIF-1alpha. 15-LOX-2 enzyme activity can be modulated by HIF-1alpha. Thus, increased expression of 15-LOX-2 in macrophages in hypoxic atherosclerotic plaque may enhance inflammation and the recruitment of inflammatory cells.

Affinity precipitation and site-specific immobilization of proteins carrying polyhistidine tails

Proteins carrying genetically attached polyhistidine tails have been purified using affinity precipitation with metal chelates. DNA fragments encoding four or five histidine residues have been genetically fused to the oligomeric enzymes lactate dehydrogenase (Bacillus stearothermophilus), beta-glucoronidase (Escherichia coli), and galactose dehydrogenase (Pseudomonas fluorescens) as well as to the monomeric protein A (Staphylococcus aureus). The chimeric genes were subsequently expressed in E. coli. The engineered enzymes were successfully purified from crude protein solutions using ethylene glycolbis (beta-aminoethyl) tetraacetic acid (EGTA) charged with Zn(2+) as precipitant, whereas protein A, carrying only one attached histidine tail, did not precipitate. However, all of the engineered proteins could be purified on immobilized metal affinity chromatography (IMAC) columns loaded with Zn(2+). The potential of using the same histidine tails for site-specific immobilization of proteins was also investigated. The enzymes were all catalytically active when immobilized on IMAC gels. For instance, immobilized lactate dehydrogenase, carrying tails composed of four histidine residues, displaced 83% of the soluble enzyme activity.

gammaH2AX and cleaved PARP-1 as apoptotic markers in irradiated breast cancer BT474 cellular spheroids

Chemo- and radiotherapy induce apoptosis in tumours and surrounding tissues. In a search for robust and reliable apoptosis markers, we have evaluated immunostaining patterns of gammaH2AX and cleaved PARP-1 in paraffin-embedded cellular spheroids. Breast cancer BT474 cells were grown as cell spheroids to diameters of 700-800 microm. The spheroids contained an outer cell layer with proliferative cells, a deeper region with quiescent cells and a central area with necrosis. They were irradiated with 5 Gy and the frequency of apoptotic cells was determined at several time points (0-144 h) and distances (0-150 microm) from the spheroids surface. gammaH2AX and cleaved PARP-1 were quantified independently. Apoptotic frequencies for the two markers agreed both temporally and spatially in the proliferative regions of the spheroids. The gammaH2AX signal was stronger and had lower background compared to cleaved PARP-1. The central necrotic region was intensely stained with cleaved PARP-1, whereas no gammaH2AX could be detected. The apoptotic frequency increased with distance from surface for all time points. However, apoptotic frequencies, above unirradiated control levels, could only be detected for the last time point, 144 h after irradiation. We have shown that the spheroid model is a practical system for evaluation of staining patterns and specificities of apoptosis markers. Also, the radial gradient provides the opportunity to study apoptosis under a range of physiological conditions within the same system. We have further shown that gammaH2AX and cleaved PARP-1 are applicable markers for apoptosis in the proliferative regions of the spheroids. However, the more intense and clear staining patterns of gammaH2AX suggests that this marker is preferable for quantification of apoptosis in spheroids and similar paraffin-embedded materials.

Radiation Therapy Through Activation of Stable Nuclides

In an investigation by the Swedish Cancer Society, an expert group described the present status, critical issues and future aspects and potentials for each of nine major areas of radiation therapy research. This report deals with radiation therapy using activation of stable nuclides.

A limiting factor for the progress of radionuclide-based cancer diagnostics and therapy--availability of suitable radionuclides

Advances in diagnostics and targeted radionuclide therapy of haematological and neuroendocrine tumours have raised hope for improved radionuclide therapy of other forms of disseminated tumours. New molecular target structures are characterized and this stimulates the efforts to develop new radiolabelled targeting agents. There is also improved understanding of factors of importance for choice of appropriate radionuclides. The choice is determined by physical, chemical, biological, and economic factors, such as a character of emitted radiation, physical half-life, labelling chemistry, chemical stability of the label, intracellular retention time, and fate of radiocatabolites and availability of the radionuclide. There is actually limited availability of suitable radionuclides and this is a limiting factor for further progress in the field and this is the focus in this article. The probably most promising therapeutic radionuclide, 211At, requires regional production and distribution centres with dedicated cyclotrons. Such centres are, with a few exceptions in the world, lacking today. They can be designed to also produce beta- and Augeremitters of therapeutic interest. Furthermore, emerging satellite PET scanners will in the near future demand long-lived positron emitters for diagnostics with macromolecular radiopharmaceuticals, and these can also be produced at such centres. To secure continued development and to meet the foreseen requirements for radionuclide availability from the medical community it is necessary to establish specialized cyclotron centres for radionuclide production.

Swedish Cancer Society Radiation Therapy Research Investigation

In an investigation by the Swedish Cancer Society, the present status, critical issues and future aspects and prospects were described by an expert group for each of nine major areas of radiation research. A summary of the investigation is presented in this report. A more extensive summary (in Swedish) can be found at www.Cancerfonden.se. It is concluded that radiation therapy plays an increasingly important role in curative and palliative tumour treatment and presents a considerable challenge to research. Several suggestions are made that could improve the possibilities for high-quality radiation therapy research in Sweden.

Therapy with Radiopharmaceuticals

In an investigation by the Swedish Cancer Society, an expert group described the present status, critical issues and future aspects and potentials for each of nine major areas of radiation therapy research. The present report deals with therapy with radiopharmaceuticals.

Dimeric HER2-specific affibody molecules inhibit proliferation of the SKBR-3 breast cancer cell line

HER2-specific affibody molecules in different formats have previously been shown to be useful tumor targeting agents for radionuclide-based imaging and therapy applications, but their biological effect on tumor cells is not well known. In this study, two dimeric ((Z(HER2:4))(2) and (Z(HER2:342))(2)) and one monomeric (Z(HER2:342)) HER2-specific affibody molecules are investigated with respect to biological activity. Both (Z(HER2:4))(2) and (Z(HER2:342))(2) were found to decrease the growth rate of SKBR-3 cells to the same extent as the antibody trastuzumab. When the substances were removed, the cells treated with the dimeric affibody molecules continued to be growth suppressed while the cells treated with trastuzumab immediately resumed normal proliferation. The effects of Z(HER2:342) were minor on both proliferation and cell signaling. The dimeric (Z(HER2:4))(2) and (Z(HER2:342))(2) both reduced growth of SKBR-3 cells and may prove therapeutically useful either by themselves or as carriers of radionuclides or other cytotoxic agents.

Effects of radiation on growth of two human tumour cell lines surviving a previous high dose, low dose-rate, radionuclide exposure

Effects of radiation on growth of two human tumour cell lines that survived a previous high dose, low dose-rate radionuclide exposure simulating intensive radionuclide therapy, were analyzed. The purpose was to investigate whether the survivors gained therapy induced changes in growth and radiation response. The U118MG, ParRes (parental resistant), and U373MG, ParSen (parental sensitive), glioma cells were used because they are known to be low dose-rate radiation resistant and sensitive, respectively. These cells were initially exposed to high dose, low dose-rate radiation for 24 h and surviving U118MG and U373MG cells formed new cultures called SurRes (surviving resistant) and SurSen (surviving sensitive), respectively. All four cell types were then exposed to graded acute radiation doses, 0-8 Gy, and analyzed for radiation induced growth disturbances. They were also analyzed regarding DNA-content and cell cycle distributions. The SurRes cells regained in most cases the same growth rate, had the same growth delays and showed generally a similar response as the original ParRes cells to the 0-8 Gy exposures. In contrast, the SurSen cells had in all cases slower growth rate and longer growth delays than the original ParSen cells after the 0-8 Gy exposures. There were no signs of radiation-induced radioresistance. The slow growing SurSen cells contained about 80% more DNA and had more cells in G1 and fewer in G2 than the ParSen cells. The conclusion is that tumour cells surviving high dose, low dose-rate, radionuclide therapy, afterwards can react differently to a new radiation exposure.

In vivo and in vitro uptake of 111In, delivered with the affibody molecule (ZEGFR:955)2, in EGFR expressing tumour cells

The epidermal growth factor receptor, EGFR, is overexpressed in many carcinomas. Targeting this receptor with radionuclides is important for imaging and therapy applications in nuclear medicine. We investigated the in vitro and in vivo properties of a new high affinity EGFR binding affibody molecule, (ZEGFR:955)2, when conjugated with CHX-A''-DTPA and labelled with 111In. The binding time patterns and retention studies were performed using cultured squamous carcinoma A431 cells that overexpress EGFR. In the in vivo studies, female BALB/c nu/nu mice carrying tumours from xenografted A431 cells were used. The in vitro studies showed EGFR specific binding, high uptake and good retention of 111In when delivered as [111In](ZEGFR:955)2. The retention after 72 h of incubation was 38.0+/-1.15% of the initial level. The biodistribution study showed a tumour specific 111In uptake of 3.8+/-1.4% of injected dose per gram tumour tissue 4 h post-injection. The tumour to blood ratio was 9.1 and the tumours could easily be visualized with a gamma camera at this time-point. 111In delivered with [111In](ZEGFR:955)2 gave an EGFR specific uptake and the results indicated that the (ZEGFR:955)2 affibody molecule is a candidate for radionuclide-based tumour imaging. Potential therapy applications are discussed.

Relationship between symptom load of gastro-oesophageal reflux disease and health-related quality of life, work productivity, resource utilization and concomitant diseases: survey of a US cohort

BACKGROUND

Analysis of the burden of gastro-oesophageal reflux disease (GERD) in relation to the severity and frequency of symptoms is essential to identify individuals and groups in whom targeted management is justified.

AIM

To describe the relationship between symptoms of GERD and self-reported health-related quality of life (HRQL), work productivity, healthcare utilization and concomitant diseases.

METHODS

US respondents to the Internet-based 2004 National Health and Wellness Survey who had self-reported GERD (n = 10,028, mean age: 52 years, 58% female) were age- and gender-matched to a control group without GERD (n = 10,028). Respondents with GERD were classified according to symptom severity and frequency. HRQL and productivity were assessed using the Short-Form 8 survey (SF-8) and Work Productivity and Activity Impairment questionnaire, respectively.

RESULTS

Symptom frequency increased with increasing symptom severity. Compared with controls, respondents with GERD had more concomitant diseases [mean difference (MD): 1.6], lower SF-8 physical and mental health scores (MD: 4.1 units and 3.1 units, respectively), increased absenteeism (MD: 0.9 h/week), reduced percent productivity at work (MD: 7.5%) and increased healthcare utilization. All tested variables deteriorated with increasing symptom severity and/or frequency.

CONCLUSIONS

Increasing severity and frequency of GERD symptoms is associated with more concomitant diseases, lower HRQL, lower work productivity and increased healthcare utilization, suggesting that patients with moderate or severe GERD should receive targeted management with the most effective treatment strategies.