High-cost drugs for rare diseases: their expenditure and value based on a regional area-based study

Background: in the field of rare diseases (RDs) most of the European studies on budget impact analysis of drugs that have been conducted often lay on theoretical assumptions and focus only on Orphan drugs (ODs). Objectives: we aimed to estimate the budget impact of specific drugs for non-oncological RDs, both ODs and non-ODs, using real-world data about patients residing in Veneto Region (Italy) and to describe its expenditure structure and dynamics. Methods: a population-based multi-source observational study was conducted using data from Regional administrative databases; an ad-hoc drugs' list specific for RDs including both ODs and non-ODs and classifying them by ATC codes has been created. Results: In 2019, the total expenditure for drugs specific for RDs was EUR 97.2 million (6.6% of the total Regional budget). The RD drug list included 58 ATC codes, of which 15 ATC had an annual budget impact over EUR 1 million ("blockbuster drugs"). The most expensive treatment was a non-OD drug (Coagulation factor VIII). The two most represented therapeutical areas were the metabolic and the hematological ones. Conclusions: Cost analyses on RD high-cost drugs expenditure should consider any specific RD drug, not only ODs. Expenditure dynamics for RD drugs are peculiar showing "blockbuster drugs". Some therapeutical areas seem to be lacking in the drug research field.

Virtual hospitals: The future of the healthcare system? An expert consensus

Today, social and healthcare systems at a global level are facing constant challenges dictated by an increasing mismatch between the demand for care services and the supply of human and economic resources. Such a situation has been exacerbated in the past two years by the Covid-19 pandemic. This has led to an increase in the leverage of digitalisation, which has proved to be a crucial tool for the development and application of new organisational models at both hospital and territorial levels, thus addressing the various criticalities already present in the system. In this sense, the Virtual Hospital has emerged as a potential model for increasing effectiveness and efficiency in delivering sociomedical services. Starting from these premises, an EFTE (estimate, feedback, talk, estimate) approach was used to acquire an expert consensus within a multidisciplinary panel of academics and healthcare managers of the Veneto Region in Italy. This article reports the expert opinion on the possible application of the Virtual Hospital model in the national context, starting from the existing international evidence and good practices, highlighting the potential advantages and barriers to its implementation. Furthermore, the article analyses the most relevant areas of investment for the development of intangible assets and the acquisition of tangible assets necessary for its implementation.

Preparing healthcare, academic institutions and notified bodies for their involvement in the innovation of medical devices under the new European regulation

INTRODUCTION

Favouring innovation by making timely medical technology available to people and by securing patients' safety is a challenge.

AREAS COVERED

The new European medical device regulation (MDR) will have a central implication in the development of new devices and could affect their innovation and availability, as well as discourage investment in research within Europe.

EXPERT OPINION

Start-ups and small companies might not be able to cope with the increasing complexity and the required changes of perspective. Healthcare institutions are facing an increasing availability of complex technologies, while data on their clinical efficacy and cost-effectiveness are rarely provided.

A partnership/collaboration between healthcare institutions, academia and private industries will enhance their own specific interests with the common goal of improving overall health and quality of life. The complexity of the subject combined with the variety of specialists and stakeholders involved requires the implementation, in hospital centres of clinical excellence, of units dedicated to the whole path of the medical device innovation. Stakeholders should quickly provide adequate measures to facilitate the complex medical device innovation path under the more stringent MDR aimed to increase safety and quality of care.

Epigenetic activation of O-linked β-N-acetylglucosamine transferase overrides the differentiation blockage in acute leukemia

Background

Overriding the differentiation blockage in acute myeloid leukemia (AML) is the most successful mode-of-action in leukemia therapy – now curing the vast majority of patients with acute promyelocytic leukemia (APL) using all-trans retinoic acid (ATRA)-based regimens. Similar approaches in other leukemia subtypes, such as IDH1/2-mutated AML, are under active investigation. We herein present successful release of the differentiation blockage upon treatment with the natural (−)-Δ⁹-Tetrahydrocannabinol isomer dronabinol in vitro and in vivo.

Methods

Cellular maturation and differentiation were followed in two patients employing whole genome methylation profiling, proteome analyses, NGS deep sequencing and multispectral imaging flow cytometry. For functional studies lentiviral OGT knock-down in vitro and ex vivo cell models were created to evaluate proliferative, apoptotic and differentiating effects of OGT in acute leukemia.

Findings

In here, we provide molecular evidence that dronbinol is capable to override the differentiation blockage of acute leukemia blasts at the state of the leukemia-initiating clone. We further identify the O-linked β-N-acetyl glucosamine (O-GlcNAc) transferase (OGT) to be crucial in this process. OGT is a master regulator enzyme adding O-GlcNAc to serine or threonine residues in a multitude of target proteins. Aberrant O-GlcNAc modification is implicated in pathologies of metabolic, neurodegenerative and autoimme diseases as well as cancers. We provide evidence that dronabinol induces transcription of OGT via epigenetic hypomethylation of the transcription start site (TSS). A lentiviral OGT-knock out approach proves the central role of OGT exerting antileukemic efficacy via a dual-mechanism of action: High concentrations of dronabinol result in induction of apoptosis, whereas lower concentrations drive cellular maturation. Most intriguingly, overriding of the differentiation blockage of acute leukemia blasts is validated in vivo following two patients treated with dronabinol.

Interpretation

In conclusion, we provide evidence for overcoming the differentiation blockage in acute leukemia in subentities beyond promyelocytic and IDH1/2-mutated leukemia and thereby identify O-GlcNAcylation as a novel (drugable) field for future leukemia research.

Funding

Unrestricted grant support by the IZKF Program of the Medical Faculty Tübingen (MMS) and Brigitte Schlieben-Lange Program as well as the Margarete von Wrangell Program of the Ministry of Science, Research and the Arts, Baden-Württemberg, Germany (KKS) and Athene Program of the excellence initiative University of Tübingen (KKS).

Abstract P4-15-05: The presence of one or multiple foci of microinvasion is not associated with an increased risk of local recurrence in women with ductal carcinoma in situ treated with breast conserving therapy

Background: Ductal Carcinoma in Situ (DCIS) is a non-invasive breast cancer often treated with breast-conserving surgery (BCS) with or without radiotherapy (RT). It is unclear if the presence of microinvasion (MI) (invasion ≤1mm) is associated with an increased risk of LR (DCIS or invasive) or invasive LR compared to women with pure DCIS. In addition, the impact of multiple foci (>2) of MI compared to pure DCIS is also unknown; therefore, it is unclear if some women with MI require more aggressive treatment. We evaluated the impact of the presence of MI and the number of foci of MI on the risks of any LR and invasive LR in a population of women with DCIS with and without MI treated with BCS.

Methods: The cohort includes all women diagnosed with pure DCIS or DCIS with MI in Ontario from 1994-2003 treated with BCS +/- RT. All cases had systematic pathology review to confirm the presence and number of foci of MI. Treatment and outcomes were ascertained through administrative databases and validated by chart review. Cox proportional hazards model was used to evaluate the impact of MI and the number of foci of MI (1 vs >2 foci) on the development of any LR and invasive LR compared to cases with pure DCIS. The 10-yr local recurrence-free survival (LRFS) and invasive LRFS rates were calculated using the Kaplan-Meier approach with differences compared using the log-rank test.

Results: The population cohort includes 2,988 women with DCIS treated by BCS (N=2,721 pure DCIS, N= 267 DCIS with MI). Median follow-up (12 years; p=.23) and median age at diagnosis (58 years; p=.17) were similar in both groups. RT was given in 58% of cases with MI and 51% of cases with pure DCIS (p=.03). Hormonal therapy was utilized in 7.1% of women with MI and 5.3% of women with pure DCIS (p=.22). LR developed in 59 (22.1%) cases with MI and 530 (19.6%) cases of pure DCIS. Women with MI were more likely to have high nuclear grade (p<.001), and larger tumor size (p<.001) compared to those without MI. On multivariable analyses adjusted for age, the presence of 1 focus of MI(HR=.92, 95% CI: .64-1.33) or ≥2 foci of MI (HR=1.26, 95% CI: .85-1.85) was not associated with an increased risk of any LR compared to cases with pure DCIS. Factors associated with any LR were age <50 years at diagnosis, RT, multifocality and high nuclear grade. The presence of 1 focus of MI (HR=.86, 95% CI: .52-1.40) or > 2 foci of MI (HR=1.45, 95% CI: .90-2.32) was also not associated with an increased risk of invasive LR compared to cases of pure DCIS. Among women treated with BCS alone, the 10 year LRFS rates were 80%, 75% and 73% for women with pure DCIS, 1 focus, >2 foci of MI (p=.10). The invasive LRFS rates were 89%, 91% and 85% (p=.26). Among women treated with BCS+RT, the 10 year LRFS rates were 87%, 88% and 80% (p=0.32) for women with pure DCIS, 1 focus or ≥2 foci of MI. The invasive LRFS rates were 93%, 90% and 86% (p=.44). There was no interaction between the presence of MI and RT.

Conclusions: Women with DCIS with one or multiple foci of microinvasion (<1mm) treated by breast conserving therapy do not have an increased risk of LR or invasive LR compared to women with pure DCIS.

Citation Format: Lalani N, Paszat L, Sutradhar R, Gu S, Fong C, Nofech-Mozes S, Hanna W, Tuck A, Youngson B, Miller N, Done SJ, Chang MC, Sengupta S, Elavathil L, Jani PA, Bonin M, Rakovitch E. The presence of one or multiple foci of microinvasion is not associated with an increased risk of local recurrence in women with ductal carcinoma in situ treated with breast conserving therapy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-15-05.

Abstract P2-12-02: Is breast-conserving therapy effective in women with large ductal carcinoma in situ (DCIS) lesions? A population-based analysis

Background: Most women diagnosed with DCIS will be treated by breast-conserving surgery (BCS) with or without radiotherapy (RT). Data on outcomes following breast-conserving therapy are predominantly based on women with small (<25mm) lesions. The paucity of data on outcomes of women with larger (>40mm) DCIS lesions leads to uncertainty of the appropriateness of breast-conserving therapy for women with larger lesions. Specifically, it is unclear if women with large tumors experience higher risks of local recurrence (LR) and invasive LR after BCS+/-RT that would preclude recommendations of breast-conserving therapy. We report the outcomes and evaluate the impact of large tumor size (>40mm) on recurrence risk in a population of women with pure DCIS treated by BCS alone or with RT.

Methods: The cohort includes all women diagnosed with DCIS in Ontario from 1994-2003 treated with BCS +/- RT; 82% had pathology review. Treatment and outcomes were ascertained through administrative databases and validated by chart review. Cox proportional hazards model was used to evaluate the impact of tumor size (≤10mm,11-25mm, 26-39mm, ≥40mm) on the development of any LR (DCIS or invasive) and invasive LR. The 10 and 15-year LR-free survival (LRFS) and invasive LRFS rates were calculated using the Kaplan-Meier method with differences compared using the log-rank test.

Results: The cohort includes 3262 women with DCIS treated by BCS (N=1635 had RT). Median age at diagnosis was 59 years (IQR 50-68 years). Median follow-up was 13 years (IQR 8-15 years). Distribution of tumor size: 707 (22%) ≤10mm, 524 (16%) 11-25mm, 107 (3%) 26-39mm, 84 (3%) ≥40mm, unable to determine in 1840 (56%). Women with lesions ≥ 40mm were more likely to be ≤50 years of age at diagnosis (p=.02), have high nuclear grade (p<.001), multifocality (p<.001), and positive margins (p<.001) compared to women with smaller lesions. On multivariable analyses adjusted for age and year of diagnosis, tumor size ≥40mm was significantly associated with an increased risk of LR compared to size ≤10mm (HR=2.5, 95%CI:1.64-3.81). Other factors associated with LR were age <50 years (p<.001), omission of RT (p<.001), high nuclear grade (p=.002), and multifocality (p=.0008). Tumor size ≥40mm was not significantly associated with an increased risk of invasive LR (HR=1.68, 95%CI:.94-3.04). Women with tumour size ≥40mm treated with BCS alone had lower 10 and 15 year LRFS (53% and 41%) and invasive LRFS rates (78% and 75%) compared to women with smaller lesions. However, women with larger lesions treated with RT had significantly higher LRFS and invasive LRFS rates

Outcomes by tumour size for women with DCIS treated with BCS with or without RT  ≤10mm N=70711-25mm N=52426-39mm N=107≥40mm N=84p-valueBCS AloneLRFS (%)      10 yr85797053<0.001 15 yr81746741  Invasive LRFS (%)      10 yr928786780.03 15 yr89838375 BCS + RTLRFS (%)      10 yr928874850.01 15 yr86847079  Invasive LRFS (%)      10 yr959492910.27 15 yr90918789 

. There was a significant interaction between tumor size ≥40mm and RT (p=.02).

Conclusions: Women with DCIS lesions ≥40mm treated by BCS alone experience significantly higher risks of LR and invasive LR compared to smaller lesions but this risk can be mitigated with the addition of RT.

Citation Format: Lalani N, Paszat L, Nofech-Mozes S, Sutradhar R, Gu S, Hanna W, Fong C, Miller N, Youngson B, Done SJ, Tuck A, Chang MC, Sengupta S, Jani PA, Bonin M, Rakovitch E. Is breast-conserving therapy effective in women with large ductal carcinoma in situ (DCIS) lesions? A population-based analysis [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-12-02.

Abstract P3-17-01: Long-term rates of breast preservation after breast-conserving therapy for ductal carcinoma in situ

Background: Despite evidence that radiotherapy (RT) after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) halves the risk of recurrence, the benefit of RT in the management of DCIS continues to be a matter of controversy. One argument against the use of RT after BCS is that patients who develop ipsilateral local recurrence (LR) can be salvaged with further breast-conserving surgery such that the omission of RT will lead to high rates of breast preservation while minimizing exposure to RT. Breast preservation is an important determinant of quality of life for women with early stage breast cancer and DCIS. Yet the management of LR and the impact of RT on the resultant long-term risks of bilateral breast preservation in a population of women with DCIS are unclear. We assessed the treatment of LR, the impact of RT on the use of salvage mastectomy and the long-term risks of bilateral breast preservation achieved in a population of women with DCIS treated with BCS alone or BCS+RT.

Methods: A population-based analysis of women diagnosed with DCIS from 1994-2003 treated with BCS alone or BCS+RT with pathology review. Treatment and outcomes, including the development of LR and contralateral breast events, were determined by administrative databases with validation by review of operative or pathology reports. Median follow-up was 10.2 years for cases treated by BCS alone, 11.6 years for those treated by BCS+RT. We used a propensity-adjusted Cox proportional hazards model to evaluate factors associated with the use of salvage mastectomy for LR and to evaluate factors associated with any mastectomy. We assessed the risk of long-term breast preservation by calculating the KM 10-year risk of ipsilateral mastectomy and any mastectomy.

Results: The population cohort includes 3303 women with pure DCIS;1649 (50%) were treated by BCS alone, 1654 (50%) received BCS+RT. Women treated with RT had more high risk features of DCIS than those treated by BCS alone. LR developed in 343 (21%) women treated by BCS alone and in 257 (15.5%) women treated by BCS+RT (p<0.01). Most women who developed LR received salvage mastectomy, irrespective of age at diagnosis and histology. Salvage mastectomy was used in 57.4% (197/343) of cases that recurred after BCS alone and in 67.6% (173/257) that recurred after BCS+RT. The likelihood of receiving salvage mastectomy for LR was similar in patients initially treated by BCS+RT vs. those initially treated BCS alone. Most (90%) of mastectomies were performed for a LR. Overall, individuals initially treated by BCS+RT had a 29% lower probability of having a mastectomy at 10 years compared to those treated by BCS alone (HR=0.71, 95%CI: 0.60,0.84,p<0.0001). The 10 year mastectomy-free survival rates are 82.7% for women initially treated by BCS alone and 87.3% for those treated by BCS+RT (p=0.0096).

Conclusion: Women who received RT after BCS for DCIS experience a greater likelihood of long-term bilateral breast preservation. This is attributable to the lower risks of LR and that most local recurrences after breast-conserving therapy are treated by salvage mastectomy. Long-term breast preservation should be considered in discussions weighing the benefits and risks of RT after conservative surgery for DCIS.

Citation Format: Rakovitch E, Nofech-Mozes S, Hanna W, Gu S, Fong C, Tuck A, Sengupta S, Elavathil L, Jani P, Done S, Miller N, Youngson B, Bonin M, Chang M, Paszat L. Long-term rates of breast preservation after breast-conserving therapy for ductal carcinoma in situ [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-17-01.

Abstract P6-09-04: Nuclear grade has a limited role in predicting recurrence in DCIS following breast conserving surgery: A population-based study

This abstract was not presented at the symposium.

PIK3R1 mutations in SHORT syndrome

SHORT syndrome (OMIM 269880) is a rare autosomal-dominant disorder characterized by short stature, hyperextensibility of joints, hernias, ocular depression, ophthalmic anomalies (Rieger anomaly, posterior embryotoxon, glaucoma), teething delay, partial lipodystrophy, insulin resistance and facial dysmorphic signs. Heterozygous mutations in PIK3R1 were recently identified in 14 families with SHORT syndrome. Eight of these families had a recurrent missense mutation (c.1945C>T; p.Arg649Trp). We report on two unrelated patients with typical clinical features of SHORT syndrome and additional problems such as pulmonary stenosis and ectopic kidney. Analysis of PIK3R1 revealed the mutation c.1945C>T; p.Arg649Trp de novo in both patients. These two patients not only provide additional evidence that PIK3R1 mutations cause SHORT syndrome, but also broaden the clinical spectrum of this syndrome and further confirm that the amino acid exchange c.1945C>T; p.Arg649Trp is a hotspot mutation in this gene.

A technical platform for generating reproducible expression data from Streptomyces coelicolor batch cultivations

Streptomyces coelicolor, the model species of the genus Streptomyces, presents a complex life cycle of successive morphological and biochemical changes involving the formation of substrate and aerial mycelium, sporulation and the production of antibiotics. The switch from primary to secondary metabolism can be triggered by nutrient starvation and is of particular interest as some of the secondary metabolites produced by related Streptomycetes are commercially relevant. To understand these events on a molecular basis, a reliable technical platform encompassing reproducible fermentation as well as generation of coherent transcriptomic data is required. Here, we investigate the technical basis of a previous study as reported by Nieselt et al. (BMC Genomics 11:10, 2010) in more detail, based on the same samples and focusing on the validation of the custom-designed microarray as well as on the reproducibility of the data generated from biological replicates. We show that the protocols developed result in highly coherent transcriptomic measurements. Furthermore, we use the data to predict chromosomal gene clusters, extending previously known clusters as well as predicting interesting new clusters with consistent functional annotations.

Colossal magnetoresistance in an ultraclean weakly interacting 2D Fermi liquid

We report the observation of a new phenomenon of colossal magnetoresistance in a 40 nm wide GaAs quantum well in the presence of an external magnetic field applied parallel to the high-mobility 2D electron layer. In a strong magnetic field, the magnetoresistance is observed to increase by a factor of ∼300 from 0 to 45 T without the system undergoing any metal-insulator transition. We discuss how this colossal magnetoresistance effect cannot be attributed to the spin degree of freedom or localization physics, but most likely emanates from strong magneto-orbital coupling between the two-dimensional electron gas and the magnetic field. Our observation is consistent with a field-induced 2D-to-3D transition in the confined electronic system.

Prenatal diagnosis of a recombinant chromosome 7 resulting in trisomy 7q11.22 --> qter

Prenatal diagnosis of trisomy 7 is complex due to only a few reported cases. We report here on a stillborn boy with very large duplication of 7q11.22 --> qter, encompassing almost the entire long arm of chromosome 7. Ultrasound, fetal and parental chromosome banding, fluorescence in situ hybridization (FISH), and array comparative genomic hybridization (CGH) analyses were performed. Sonographic findings included growth retardation, micrognathia, ventricular septal defect (VSD), aortic coarctation, bradyarrhythmia, pericardial effusion, bilateral hydronephrosis, infravesical obstruction, and cerebellar hypoplasia. Chromosome analysis after cordocentesis at 23 weeks of gestation revealed an abnormal male karyotype with 46 chromosomes and a derivative chromosome 7 with a very large duplication of the long arm, 46,XY,der(7)(qter --> q11.2::p22 --> qter). The mother was found to carry an apparently balanced pericentric inversion, 46,XX,inv(7)(p22q11.2). Thus, the recombinant chromosome 7 [rec(7)dup(7q)inv(7)(p22.3q11.22)mat] of the fetus must have arisen through meiotic crossing-over between the inverted chromosome and the normal chromosome 7 in the maternal germline. FISH and array CGH results confirmed the recombinant chromosome 7 in the fetus and indicated a loss of 1.9 Mb at chromosome 7pter --> p22.3 (pter to 1,948,072 bp), and a gain of 87.04 Mb at chromosome 7q11.22 --> qter (71,760,154 bp to qter). The rare syndrome of almost complete trisomy 7q may be suspected in cases of growth retardation, cerebellar hypoplasia, micrognathia, aortic coarctation and VSD and hydronephrosis. Invasive prenatal diagnosis must be offered to the parents.

Expression profiling in peripheral blood reveals signature for penetrance in DYT1 dystonia

DYT1 dystonia is an autosomal-dominantly inherited movement disorder, which is usually caused by a GAG deletion in the TOR1A gene. Due to the reduced penetrance of approximately 30-40%, the determination of the mutation in a subject is of limited use with regard to actual manifestation of symptoms. In the present study, we used Affymetrix oligonucleotide microarrays to analyze global gene expression in blood samples of 15 manifesting and 15 non-manifesting mutation carriers in order to identify a susceptibility profile beyond the GAG deletion which is associated with the manifestation of symptoms in DYT1 dystonia. We identified a genetic signature which distinguished between asymptomatic mutation carriers and symptomatic DYT1 patients with 86.7% sensitivity and 100% specificity. This genetic signature could correctly predict the disease state in an independent test set with a sensitivity of 87.5% and a specificity of 85.7%. Conclusively, this genetic signature might provide a possibility to distinguish DYT1 patients from asymptomatic mutation carriers.

Autosomal dominant spastic paraplegia with peripheral neuropathy maps to chr12q23-24

OBJECTIVE

Hereditary spastic paraplegias (HSP) are genetically exceedingly heterogeneous. To date, 37 genetic loci for HSP have been described (SPG1-41), among them 16 loci for autosomal dominant disease. Notwithstanding, further genetic heterogeneity is to be expected in HSP, as various HSP families do not link to any of the known HSP loci. In this study, we aimed to map the disease locus in a German family segregating autosomal dominant complicated HSP.

METHODS

A genome-wide linkage analysis was performed using the GeneChip Mapping 10Kv2.0 Xba Array containing 10,204 SNP markers. Suggestive loci were further analyzed by mapping of microsatellite markers.

RESULTS

One locus on chromosome 12q23-24, termed SPG36, was confirmed by high density microsatellite fine mapping with a significant LOD score of 3.2. SPG36 is flanked by markers D12S318 and D12S79. Linkage to SPG36 was excluded in >20 additional autosomal dominant HSP families. Candidate genes were selected and sequenced. No disease-causing mutations were identified in the coding regions of ATXN2, HSPB8, IFT81, Myo1H, UBE3B, and VPS29. SPG36 is complicated by a sensory and motor neuropathy; it is therefore the eighth autosomal dominant subtype of complicated HSP.

CONCLUSION

We report mapping of a new locus for autosomal dominant hereditary spastic paraplegia (HSP) (SPG36) on chromosome 12q23-24 in a German family with autosomal dominant HSP complicated by peripheral neuropathy.

Specific transcriptional changes in human fetuses with autosomal trisomies

Among full autosomal trisomies, only trisomies of chromosome 21 (Down syndrome), 18 (Edwards syndrome) and 13 (Patau syndrome) are compatible with postnatal survival. But the mechanisms, how a supernumerary chromosome disrupts the normal development and causes specific phenotypes, are still not fully explained. As an alternative to gene dosage effect due to the trisomic chromosome a genome-wide transcriptional dysregulation has been postulated. The aim of this study was to define the transcriptional changes in trisomy 13, 18, and 21 during early fetal development in order to obtain more insights into the molecular etiopathology of aneuploidy. Using oligonucleotide microarrays, we analyzed whole genome expression profiles in cultured amniocytes (AC) and chorionic villus cells (CV) from pregnancies with a normal karyotype and with trisomies of human chromosomes 13, 18 and 21. We observed a low to moderate up-regulation for a subset of genes of the trisomic chromosomes. Transcriptional levels of most of the genes on the supernumerary chromosome appeared similar to the respective chromosomal pair in normal karyotypes. A subset of chromosome 21 genes including the DSCR1 gene involved in fetal heart development was consistently up-regulated in different prenatal tissues (AC, CV) of trisomy 21 fetuses whereas only minor changes were found for genes of all other chromosomes. In contrast, in trisomy 18 vigorous downstream transcriptional changes were found. Global transcriptome analysis for autosomal trisomies 13, 18, and 21 supported a combination of the two major hypotheses.

RNA interference of LRRK2-microarray expression analysis of a Parkinson's disease key player

The protein leucine-rich repeat kinase 2 (LRRK2) is a key player in the pathogenesis of Parkinson's disease (PD). Mutations in the LRRK2 gene account for up to 10% of all autosomal dominant forms of familiar and for approximately 1-3% of sporadic PD patients. Although the LRRK2 protein has many functional domains like a leucine-rich repeat domain, a Roc-GTPase domain, a kinase domain of the tyrosine kinase-like subfamily and multiple protein interaction domains (armadillo, ankyrin, WD40), the exact biological role of LRRK2 in the human brain is elusive. To gain more insight into the biological function of this protein, we monitored the changes in the expression profiles of SH-SY5Y cells, a dopaminergic neuroblastoma cell line, induced by a depletion of LRRK2 levels by RNA interference (RNAi) with Affymetrix U133 Plus 2.0 microarrays. A total of 187 genes were differentially regulated by at least a 1.5-fold change with 94 transcripts being upregulated and 93 transcripts being downregulated compared to scrambled control siRNA transfected cells. Key players of the interaction networks were independently verified by qRT-PCR. The differentially expressed gene products are involved in axonal guidance, nervous system development, cell cycle, cell growth, cell differentiation, cell communication, MAPKKK cascade, and Ras protein signal transduction. Defined gene expression networks will now serve to look more closely for candidates affected by LRRK2 reduction and how they might be altered in other forms of familial or sporadic PD.

Overexpression of human wildtype torsinA and human DeltaGAG torsinA in a transgenic mouse model causes phenotypic abnormalities

Primary torsion dystonia is an autosomal-dominant inherited movement disorder. Most cases are caused by an in-frame deletion (GAG) of the DYT1 gene encoding torsinA. Reduced penetrance and phenotypic variability suggest that alteration of torsinA amino acid sequence is necessary but not sufficient for development of clinical symptoms and that additional factors must contribute to the factual manifestation of the disease. We generated 4 independent transgenic mouse lines, two overexpressing human mutant torsinA and two overexpressing human wildtype torsinA using a strong murine prion protein promoter. Our data provide for the first time in vivo evidence that not only mutant torsinA is detrimental to neuronal cells but that also wildtype torsinA can lead to neuronal dysfunction when overexpressed at high levels. This hypothesis is supported by (i) neuropathological findings, (ii) neurochemistry, (iii) behavioral abnormalities and (iv) DTI-MRI analysis.

F-ara-A pharmacokinetics during reduced-intensity conditioning therapy with fludarabine and busulfan

Fludarabine is commonly used in combination with busulfan as part of conditioning regimens before allogeneic stem cell transplantation. So far, no data are available on busulfan-fludarabine drug interactions in transplant recipients. The pharmacokinetic (PK) properties of F-ara-A (9-beta-D-arabinosyl-2-fluoradenine) before and after application of busulfan were prospectively investigated in 16 patients with hematological malignancies. The conditioning regimen consisted of intravenous fludarabine 30 mg/m(2) over 30 min from day -6 to day -3, and oral busulfan given at 1 mg/kg every 6 h from day -5 to day -2. PK parameters of F-ara-A, derived from plasma and urine on day -6, -5, -4 and -3, were determined using high-performance liquid chromatography (HPLC). AUC, C(max), t(1/2), Cl(total) and V(SS) were 21.9 microMh, 3.5 microM, 13.0 h, 4.3 l/h/m(2), 60.0 l/m(2) on day -6 and 22.4 microMh, 3.5 microM, 14.0 h, 4.7 l/h/m(2), 69.0 l/m(2) on day -5 to (-2), respectively. Cl(renal) and the urine-recovery were 4.8 l/h, 43.7% of the fludarabine dose on day -6 and 3.9 l/h, 44.2% of the fludarabine dose on day -5 to (-2), respectively. There were no changes in PK parameters of fludarabine given before and after intake of busulfan. This implies that a clinically relevant busulfan-fludarabine drug interaction is unlikely.