39 research outputs found
Evaluation of a flexible NOTA-RGD kit solution using Gallium-68 from different ⁶⁸Ge/⁶⁸Ga-generators : pharmacokinetics and biodistribution in nonhuman primates and demonstration of solitary pulmonary nodule imaging in humans
PURPOSE : Radiopharmaceuticals containing the motive tripeptide arginyl-glycyl-asparatic acid (RGD) are known to target ανβ3 integrins during tumor angiogenesis. A more generic kit radiolabeling procedure accommodating Ga-68 from different generators was developed for NOTA-RGD and evaluated for its versatile use and safety in subsequent in vivo applications. The [⁶⁸Ga]NOTA-RGD kit was further verified for its expected biodistribution and pharmacokinetics in nonhuman primates and its clinical sensitivity to detect solitary pulmonary nodules (SPN) in cancer patients. PROCEDURES : Single vial kits containing 28–56 nmol of NOTA-cyclo-Arg-Gly-Asp-d-Tyr-Lys (NOTA-RGD) and sodium acetate trihydrate buffer were formulated. Versatility of the NOTARGD radiolabeling performance and adaption to a TiO2- and a SnO2-based generator type, characterization and long-term storage stability of the kits were carried out. The blood clearance and urine recovery kinetics as well as the image-guided biodistribution of [⁶⁸Ga]NOTA-RGD was studied in a vervet monkey model. [⁶⁸Ga]NOTA-RGD kits were further tested clinically to target solitary pulmonary nodules. RESULTS : The kits could be successfully formulated warranting integrity over 3–4 months with a good [⁶⁸Ga]NOTA-RGD radiolabeling performance (radiochemical purity 995 %, decay corrected yield 76–94 %, specific activity of 8.8–37.9 GBq/μmol) The kits met all quality requirements to be further tested in vivo. [⁶⁸Ga]NOTA-RGD cleared rapidly from blood and was majorly excreted via the renal route. The liver, spleen, heart and intestines showed initial uptake with steadily declining tissue activity concentration over time. In addition, the [⁶⁸Ga]NOTA-RGD kit allowed for delineation of SPN from non-malignant lung tissue in humans. CONCLUSIONS : A more versatile radiolabeling procedure using kit-formulated NOTA-RGD and different generator types was achieved. The uncompromised in vivo behavior and efficient targeting of SPN warrants further investigations on the clinical relevance of [⁶⁸Ga]NOTA-RGD derivatives to implement initial guidelines and management of patients, with regard to integrin targeted imaging.Nuclear Technologies in Medicine and the Biosciences Initiative (NTeMBIhttps://link.springer.com/journal/113072018-06-30Nuclear Medicin
A Replication Study of the Association between Rheumatoid Arthritis and Deletion of the Late Cornified Envelope Genes LCE3B and LCE3C
OBJECTIVE: Two recent studies, in a Spanish and a Chinese population, point to an association between rheumatoid arthritis (RA) risk and the deletion of the Late Cornified Envelope (LCE) 3B and 3C genes (LCE3C_LCE3B-del), a known risk factor for psoriasis. We aimed to replicate these studies in a large Dutch cohort. METHODS: 1039 RA cases and 759 controls were genotyped for LCE3C_LCE3B-del. Association analysis was performed for the complete cohort and after stratification for the serologic markers anti-cyclic citrullinated peptide and rheumatoid factor. A meta-analysis was performed combining our data with the Spanish and Chinese datasets, resulting in an analysis including 2466 RA cases and 2438 controls. RESULTS: In the Dutch cohort we did not observe a significant association of LCE3C_LCE3B-del (p = 0.093) with RA risk. A stratified analysis for the serologic positive and negative group did not show an association between the genetic variant and disease risk, either. The meta-analysis, however, confirmed a significant association (p<0.0001, OR = 1.31, 95% confidence interval 1.16-1.47). CONCLUSION: Our meta-analysis confirms the association of the LCE3 deletion with RA, suggesting that LCE3C_LCE3B-del is a common risk factor for (auto)immune diseases
Focal structural variants revealed by whole genome sequencing disrupt the histone demethylase KDM4C in B cell lymphomas
Histone methylation-modifiers, like EZH2 and KMT2D, are recurrently altered in B-cell lymphomas. To comprehensively describe the landscape of alterations affecting genes encoding histone methylation-modifiers in lymphomagenesis we investigated whole genome and transcriptome data of 186 mature B-cell lymphomas sequenced in the ICGC MMML-Seq project. Besides confirming common alterations of KMT2D (47% of cases), EZH2 (17%), SETD1B (5%), PRDM9 (4%), KMT2C (4%), and SETD2 (4%) also identified by prior exome or RNAseq studies, we here unravel KDM4C in chromosome 9p24, encoding a histone demethylase, to be recurrently altered. Focal structural variation was the main mechanism of KDM4C alterations, which was independent from 9p24 amplification. We identified KDM4C alterations also in lymphoma cell lines including a focal homozygous deletion in a classical Hodgkin lymphoma cell line. By integrating RNAseq and genome sequencing data we predict KDM4C structural variants to result in loss-of-function. By functional reconstitution studies in cell lines, we provide evidence that KDM4C can act as tumor suppressor. Thus, we show that identification of structural variants in whole genome sequencing data adds to the comprehensive description of the mutational landscape of lymphomas and, moreover, establish KDM4C as putative tumor suppressive gene recurrently altered in subsets of B-cell derived lymphomas
Developing and testing a nurse-led intervention to support bereavement in relatives in the intensive care (BRIC study): a protocol of a pre-post intervention study
BACKGROUND: When a patient is approaching death in the intensive care unit (ICU), patients' relatives must make a rapid transition from focusing on their beloved one's recovery to preparation for their unavoidable death. Bereaved relatives may develop complicated grief as a consequence of this burdensome situation; however, little is known about appropriate options in quality care supporting bereaved relatives and the prevalence and predictors of complicated grief in bereaved relatives of deceased ICU patients in the Net
DNA methylome analysis in Burkitt and follicular lymphomas identifies differentially methylated regions linked to somatic mutation and transcriptional control
Although Burkitt lymphomas and follicular lymphomas both have features of germinal center B cells, they are biologically and clinically quite distinct. Here we performed whole-genome bisulfite, genome and transcriptome sequencing in 13 IG-MYC translocation-positive Burkitt lymphoma, nine BCL2 translocation-positive follicular lymphoma and four normal germinal center B cell samples. Comparison of Burkitt and follicular lymphoma samples showed differential methylation of intragenic regions that strongly correlated with expression of associated genes, for example, genes active in germinal center dark-zone and light-zone B cells. Integrative pathway analyses of regions differentially methylated in Burkitt and follicular lymphomas implicated DNA methylation as cooperating with somatic mutation of sphingosine phosphate signaling, as well as the TCF3-ID3 and SWI/SNF complexes, in a large fraction of Burkitt lymphomas. Taken together, our results demonstrate a tight connection between somatic mutation, DNA methylation and transcriptional control in key B cell pathways deregulated differentially in Burkitt lymphoma and other germinal center B cell lymphomas
Production of high specific activity 195mPt‐cisplatinum at South African Nuclear Energy Corporation for Phase 0 clinical trials in healthy individual subjects
Platinum agents continue to be the main chemotherapeutic agents used in the first-line and second-line treatments of cancer
patients. It is important to fully understand the biological profile of these compounds in order to optimize the dose given to each
patient. In a joint project with the Australian Nuclear Science and Technology Organisation and the Nuclear Medicine Department
at Steve Biko Academic Hospital, South African Nuclear Energy Corporation synthesized and supplied 195mPt-cisplatinum
(commonly referred to as cisplatin) for a clinical pilot study on healthy volunteers. Enriched 194PtCl2 was prepared by digestion
of enriched 194Pt metal (>95%) followed by thermal decomposition over a 3 h period. The 194PtCl2 was then placed in a quartz
ampoule, was irradiated in SAFARI-1 up to 200 h, then decay cooled for a minimum of 34 h prior to synthesis of final product.
195mPt(NH3)2I2, formed with the addition of KI and NH4OH, was converted to the diaqua species [195mPt(NH3)2(H2O)2]2+ by reaction
with AgNO3. The conversion to 195mPt-cisplatinum was completed by the addition of concentrated HCl. The final product yield was
51.7%± 5.2% (n = 5). The chemical and radionuclidic purity in each case was >95%.
The use of a high flux reactor position affords a higher specific activity product (15.9±2.5MBq/mg at end of synthesis) than
previously found (5MBq/mg). Volunteers received between 108 and 126MBq of radioactivity, which is equivalent to 6.8–10.0mg
of carrier cisplatinum. Such high specific activities afforded a significant reduction (~50%) in the chemical dose of a carrier cisplatinum,
which represents less than 10%of a typical chemotherapeutic dose given to patients. A goodmanufacturing practice GMP compliant
product was produced and was administered to 10 healthy volunteers as part of an ethically approved Phase 0 clinical trial. The
majority of the injected activity 27.5%± 5.8% was excreted in the urine within 5 h post injection (p.i.). Only 8.5%± 3.1% of
cisplatinumremained in blood pools at 5 h,which gradually cleared over the 6-daymonitoring period p.i. At the end of the study
(6 days p.i.), a total of 37.4%± 5.3% of the product had cleared from the blood into urine, and approximately 63% remained in
the body. The significantly lower concentration of carrier cisplatinum used for imaging resulted in a well-tolerated product
Development of a single vial kit solution for radiolabeling of 68Ga-DKFZ-PSMA-11 and its performance in prostate cancer patients
Prostate-specific membrane antigen (PSMA), a type II glycoprotein, is highly expressed in almost all prostate cancers. By playing such a universal role in the disease, PSMA provides a target for diagnostic imaging of prostate cancer using positron emission tomography/computed tomography (PET/CT). The PSMA-targeting ligand Glu-NH-CO-NH-Lys-(Ahx)-HBED-CC (DKFZ-PSMA-11) has superior imaging properties and allows for highly-specific complexation of the generator-based radioisotope Gallium-68 (68Ga). However, only module-based radiolabeling procedures are currently available. This study intended to develop a single vial kit solution to radiolabel buffered DKFZ-PSMA-11 with 68Ga. A 68Ge/68Ga-generator was utilized to yield 68GaCl3 and major aspects of the kit development were assessed, such as radiolabeling performance, quality assurance, and stability. The final product was injected into patients with prostate cancer for PET/CT imaging and the kit performance was evaluated on the basis of the expected biodistribution, lesion detection, and dose optimization. Kits containing 5 nmol DKFZ-PSMA-11 showed rapid, quantitative 68Ga-complexation and all quality measurements met the release criteria for human application. The increased precursor content did not compromise the ability of 68Ga-DKFZ-PSMA-11 PET/CT to detect primary prostate cancer and its advanced lymphatic- and metastatic lesions. The 68Ga-DKFZ-PSMA-11 kit is a robust, ready-to-use diagnostic agent in prostate cancer with high diagnostic performance
Modelling of the blood plasma species of biguanide derivatives exhibiting potential as diagnostic radiopharmaceuticals
99mTc-DMSA (DMSA=dimercaptosuccinic acid), the gold standard for static renal imaging, has a long uptake time, which is a limiting factor in diagnostic procedures and also leads to a relatively high radiation dose to patients. The ligands dimethyl biguanide (DMBG), biuret (BIU), 2-imino-4-thiobiuret (ITB) and carboxy-biguanide (CBIG) have nitrogen donor atoms, which are able to complex transition elements. The formation constants needed in order to establish a blood plasma model for these ligands were determined by potentiometry and the results are reported herein. Based on blood plasma modelling, it was shown that the ligands had selectivity for 99mTc over blood plasma metal ions at physiological pH and it was therefore hypothesized that the Tc-ligand complex would survive in blood plasma. Furthermore, no or few side effects related to the mobilization of blood plasma metal ions by these ligands are expected, once the radiopharmaceutical has been administered. It is also expected that these ligands should clear rapidly from the blood plasma
The anti-tumour properties and biodistribution (as determined by the radiolabeled equivalent) of Au-compounds intended as potential chemotherapeutics
The anti-tumour activity of the Au (I) phosphine complex [Au(dppe2]Cl was first discovered in the mid 1980s although promising results were obtained it did not pass clinical studies because of its toxicity to organs such as the liver and heart. The aim of this study was to determine whether the two novel gold compounds (MM5 and MM6), selected for this study, have higher selectivity for cancer cells with less toxicity towards normal cells than [Au(dppe)2]Cl, and also to determine whether they have improved bio distribution compared to [Au(dppe)2]Cl. The Au-compounds as potential chemotherapeutic drugs were evaluated by using radioactive tracers in the in vitro and in vivo studies.
Results obtained from these experiments showed that the uptake of these experimental compounds was dependent on their octanol/water partition coefficient. However; the inhibition of cell growth did not correlate with the uptake of these compounds by the cells that were tested.
In terms of the total uptake it was found that the compounds that were less lipophilic (MM5, MM6) were taken up less efficiently in cells than those that are more lipophilic. Therefore hydrophilic drugs are expected to have a limited biodistribution compared to lipophilic drugs. This might imply a more selective tumour uptake