Osteoporosis and bisphosphonates-related osteonecrosis of the jaw: Not just a sporadic coincidence - a multi-centre study

Bisphosphonates (BPs) are powerful drugs that inhibit bone metabolism. Adverse side effects are rare but potentially severe such as bisphosphonate-related osteonecrosis of the jaw (BRONJ). To date, research has primarily focused on the development and progression of BRONJ in cancer patients with bone metastasis, who have received high dosages of BPs intravenously. However, a potential dilemma may arise from a far larger cohort, namely the millions of osteoporosis patients on long-term oral BP therapy.

PTCH promoter methylation at low level in sporadic basal cell carcinoma analysed by three different approaches

Please cite this paper as: PTCH promoter methylation at low level in sporadic basal cell carcinoma analysed by three different approaches. Experimental Dermatology 2010. Abstract: Basal cell carcinoma (BCC) is the most common form of skin cancer. Mutations of the PTCH hallmark gene are detected in about 50-60% of BCCs, which raises the question whether other mechanisms such as promoter methylation can inactivate PTCH. Therefore, we performed methylation analysis of the PTCH promoter in a total of 56 BCCs. The sensitivity of three different methods, including direct bisulphite sequencing PCR, MethyLight and high-resolution melting (HRM), was applied and compared. We found that HRM analysis of DNA from fresh tissue [rather than formalin-fixed and paraffin-embedded tissue (FFPE)] was the most sensitive method to detect methylation. Low-level methylation of the PTCH promoter was detected in five out of 16 analysed BCCs (31%) on DNA from fresh tissue but only in two (13%) samples on short-time stored FFPE DNA from the very same tumors. In contrast, we were unable to detect methylation by HRM on long-time stored DNA in any of the remaining 40 BCC samples. Our data suggest that (i) HRM on DNA extracted from fresh tissue is the most sensitive method to detect methylation and (ii) methylation of the PTCH promoter may only play a minor role in BCC carcinogenesis.

Sleep-wake disturbances in sporadic Creutzfeldt-Jakob disease

BACKGROUND: The prevalence and characteristics of sleep-wake disturbances in sporadic Creutzfeldt-Jakob disease (sCJD) are poorly understood. METHODS: Seven consecutive patients with definite sCJD underwent a systematic assessment of sleep-wake disturbances, including clinical history, video-polysomnography, and actigraphy. Extent and distribution of neurodegeneration was estimated by brain autopsy in six patients. Western blot analyses enabling classification and quantification of the protease-resistant isoform of the prion protein, PrPSc, in thalamus and occipital cortex was available in four patients. RESULTS: Sleep-wake symptoms were observed in all patients, and were prominent in four of them. All patients had severe sleep EEG abnormalities with loss of sleep spindles, very low sleep efficiency, and virtual absence of REM sleep. The correlation between different methods to assess sleep-wake functions (history, polysomnography, actigraphy, videography) was generally poor. Brain autopsy revealed prominent changes in cortical areas, but only mild changes in the thalamus. No mutation of the PRNP gene was found. CONCLUSIONS: This study demonstrates in sporadic Creutzfeldt-Jakob disease, first, the existence of sleep-wake disturbances similar to those reported in fatal familial insomnia in the absence of prominent and isolated thalamic neuronal loss, and second, the need of a multimodal approach for the unambiguous assessment of sleep-wake functions in these patients.

Sporadic bloody diarrhoea-associated thrombotic thrombocytopenic purpura-haemolytic uraemic syndrome: an adult and paediatric comparison

Although diarrhoea-associated haemolytic uremic syndrome (HUS) in children is well described, the clinical features of bloody diarrhoea-associated thrombotic thrombocytopenic purpura (TTP)-HUS in adults are not documented. Twenty-one adults, 6.5% of the 322 adults in The Oklahoma TTP-HUS Registry, 1989-2006, have presented with bloody diarrhoea. There were no case clusters. Escherichia coli O157:H7 was identified in five patients, but many patients did not have appropriate studies. The annual incidence was 0.68/10(6), 10-fold less than the incidence of diarrhoea-associated HUS in children in Oklahoma. Two (13%) of 16 patients in whom ADAMTS13 (A Disintegrin And Metalloproteinase with a ThromboSpondin type 1 motif, member 13) was measured had <10% activity. Severe neurological abnormalities (67%) and renal failure (62%) were common; seven patients (33%) died; no survivors have relapsed. Compared to the 38 other Oklahoma Registry patients with ADAMTS13 <10%, frequency of severe neurological abnormalities and death was not different; frequency of renal failure was greater; frequency of relapse was less. Compared to 5999 children with sporadic diarrhoea-associated HUS in published reports, frequency of renal failure and relapse was not different; frequency of severe neurological abnormalities and death was greater (P < 0.05 for all differences). Awareness of the continuous occurrence of sporadic bloody diarrhoea-associated TTP-HUS in adults is important for prompt diagnosis and appropriate management.

A case-control study of sporadic Creutzfeldt-Jakob disease in Switzerland: analysis of potential risk factors with regard to an increased CJD incidence in the years 2001-2004

BACKGROUND: In 2001, the observed annual mortality from Creutzfeldt-Jakob disease (CJD) in Switzerland increased from less than 1.5 to 2.6 per million inhabitants. An underlying cause could not be identified. METHODS: To analyse potential risk factors for sCJD in Switzerland, close relatives of 69 sCJD-patients and 224 frequency age-matched controls were interviewed in a case-control study using a standardised questionnaire. 135 potential risk factors including socio-demographics, medical history, occupation and diet were analysed by logistic regression adjusting for age, sex and education. RESULTS: sCJD patients were more likely to have travelled abroad, worked at an animal laboratory, undergone invasive dental treatment, orthopaedic surgery, ophthalmologic surgery after 1980, regular GP visits, taken medication regularly, and consumed kidney. No differences between patients and controls were found for residency, family history, and exposure to environmental and other dietary factors. CONCLUSION: Although some factors were significantly more frequent among sCJD-cases, this study did not reveal specific explanations for the increased incidence of deaths due to sporadic CJD observed in Switzerland since 2001. Results have to be interpreted with caution due to multiple testing and possible recall bias in association with a long incubation period. The most plausible reason for the increase in Swiss sCJD cases after 2000 is an improved case ascertainment. Therefore, underreporting of cases might well have occurred before the year 2001, and the "real" yearly incidence of sCJD might not be lower than, but rather above 2 per million inhabitants.

VHL inactivation is an important pathway for the development of malignant sporadic pancreatic endocrine tumors

A small subset of familial pancreatic endocrine tumors (PET) arises in patients with von Hippel-Lindau syndrome and these tumors may have an adverse outcome compared to other familial PET. Sporadic PET rarely harbors somatic VHL mutations, but the chromosomal location of the VHL gene is frequently deleted in sporadic PET. A subset of sporadic PET shows active hypoxia signals on mRNA and protein level. To identify the frequency of functionally relevant VHL inactivation in sporadic PET and to examine a possible prognostic significance we correlated epigenetic and genetic VHL alterations with hypoxia signals. VHL mutations were absent in all 37 PETs examined. In 2 out of 35 informative PET (6%) methylation of the VHL promoter region was detected and VHL deletion by fluorescence in situ hybridization was found in 14 out of 79 PET (18%). Hypoxia inducible factor 1alpha (HIF1-alpha), carbonic anhydrase 9 (CA-9), and glucose transporter 1 (GLUT-1) protein was expressed in 19, 27, and 30% of the 152 PETs examined. Protein expression of the HIF1-alpha downstream target CA-9 correlated significantly with the expression of CA-9 RNA (P<0.001), VHL RNA (P<0.05), and VHL deletion (P<0.001) as well as with HIF1-alpha (P<0.005) and GLUT-1 immunohistochemistry (P<0.001). These PET with VHL alterations and signs of hypoxia signalling were characterized by a significantly shortened disease-free survival. We conclude that VHL gene impairment by promoter methylation and VHL deletion in nearly 25% of PET leads to the activation of the HIF-pathway. Our data suggest that VHL inactivation and consecutive hypoxia signals may be a mechanism for the development of sporadic PET with an adverse outcome.

A 4-year study on clinical characteristics of children hospitalized with rotavirus gastroenteritis

Rotavirus (RV) is a frequent cause of severe gastroenteritis (GE) in children. With the licensure of new RV vaccines, data on the burden of disease are important regarding immunization strategies. We reviewed the medical records of children hospitalized with RV infection in our institution between July 2002 and March 2006. Relevant data were extracted in a standardized fashion from records of hospitalized children with a positive RV antigen test in a stool sample. Severity of disease was graded by the 20-point Vesikari score. Population data were obtained from the Federal Office of Statistics. Six hundred eighty-six RVGE were identified and records of 608 hospitalizations (in 607 children) were available. In 539 (89%) cases, RVGE was the primary reason for hospitalization and 69 (11%) were nosocomial infections; yearly peaks occurred between February and May. Cumulative incidence of RVGE was 26.7/1,000 children <3 years of age. Median age of 539 children (55.6% male) with primary RVGE was 1.4 years and median stay in the hospital for both community acquired and nosocomial RVGE was 4 days (interquartile range 3-5). Thirtypercent and 94% of RV hospitalizations were in children <1 and <3 years of age, respectively. Mean Vesikari score was 15 (range 6-20; 96% >11). Intravenous fluids were administered in 378 (70%) patients, 130 (24%) patients were rehydrated via nasogastral tube, and 31 (5.7%) received rehydration by mouth. RVGE causes a substantial burden in children with an estimated risk for hospitalization due to RVGE of one in 37 children <3 years of age.

Global phylogenomic analysis of nonencapsulated Streptococcus pneumoniae reveals a deep-branching classic lineage that is distinct from multiple sporadic lineages.

The surrounding capsule of Streptococcus pneumoniae has been identified as a major virulence factor and is targeted by pneumococcal conjugate vaccines (PCV). However, nonencapsulated Streptococcus pneumoniae (Non-Ec-Sp) have also been isolated globally, mainly in carriage studies. It is unknown if Non-Ec-Sp evolve sporadically, if they have high antibiotic non-susceptiblity rates and a unique, specific gene content. Here, whole genome sequencing of 131 Non-Ec-Sp isolates sourced from 17 different locations around the world was performed. Results revealed a deep-branching classic lineage that is distinct from multiple sporadic lineages. The sporadic lineages clustered with a previously sequenced, global collection of encapsulated S. pneumoniae (Ec-Sp) isolates while the classic lineage is comprised mainly of the frequently identified multi-locus sequences types ST344 (n=39) and ST448 (n=40). All ST344 and nine ST448 isolates had high non-susceptiblity rates to β-lactams and other antimicrobials. Analysis of the accessory genome reveals that the classic Non-Ec-Sp contained an increased number of mobile elements, than Ec-Sp and sporadic Non-Ec-Sp. Performing adherence assays to human epithelial cells for selected classic and sporadic Non-Ec-Sp revealed that the presence of a integrative conjugative element (ICE) results in increased adherence to human epithelial cells (P=0.005). In contrast, sporadic Non-Ec-Sp lacking the ICE had greater growth in vitro possibly resulting in improved fitness. In conclusion, Non-Ec-Sp isolates from the classic lineage have evolved separately. They have spread globally, are well adapted to nasopharyngeal carriage and are able to coexist with Ec-Sp. Due to continued use of pneumococcal conjugate vaccines, Non-Ec-Sp may become more prevalent.

Prognostic and predictive roles of MGMT protein expression and promoter methylation in sporadic pancreatic neuroendocrine neoplasms.

BACKGROUND/AIMS O(6)-methylguanine-methyltransferase (MGMT) is an important enzyme of DNA repair. MGMT promoter methylation is detectable in a subset of pancreatic neuroendocrine neoplasms (pNEN). A subset of pNEN responds to the alkylating agent temozolomide (TMZ). We wanted to correlate MGMT promoter methylation with MGMT protein loss in pNEN, correlate the findings with clinico-pathological data and determine the role of MGMT to predict response to TMZ chemotherapy. METHODS We analysed a well-characterized collective of 141 resected pNEN with median follow-up of 83 months for MGMT protein expression and promoter methylation using methylation-specific PCR (MSP). A second collective of 10 metastasized, pretreated and progressive patients receiving TMZ was used to examine the predictive role of MGMT by determining protein expression and promoter methylation using primer extension-based quantitative PCR. RESULTS In both collectives there was no correlation between MGMT protein expression and promoter methylation. Loss of MGMT protein was associated with an adverse outcome, this prognostic value, however, was not independent from grade and stage in multivariate analysis. Promoter hypermethylation was significantly associated with response to TMZ. CONCLUSION Loss of MGMT protein expression is associated with adverse outcome in a surgical series of pNET. MGMT promoter methylation could be a predictive marker for TMZ chemotherapy in pNEN, but further, favourably prospective studies will be needed to confirm this result and before this observation can influence clinical routine.

Sporadic late-onset nemaline myopathy with MGUS: long-term follow-up after melphalan and SCT.

OBJECTIVE Sporadic late-onset nemaline myopathy (SLONM) is a rare, late-onset myopathy that progresses subacutely. If associated with a monoclonal gammopathy of unknown significance (MGUS), the outcome is unfavorable: the majority of these patients die within 1 to 5 years of respiratory failure. This study aims to qualitatively assess the long-term treatment effect of high-dose melphalan (HDM) followed by autologous stem cell transplantation (SCT) in a series of 8 patients with SLONM-MGUS. METHODS We performed a retrospective case series study (n = 8) on the long-term (1-8 years) treatment effect of HDM followed by autologous SCT (HDM-SCT) on survival, muscle strength, and functional capacities. RESULTS Seven patients showed a lasting moderate-good clinical response, 2 of them after the second HDM-SCT. All of them had a complete, a very good partial, or a partial hematologic response. One patient showed no clinical or hematologic response and died. CONCLUSIONS This case series shows the positive effect of HDM-SCT in this rare disorder. Factors that may portend an unfavorable outcome are a long disease course before the hematologic treatment and a poor hematologic response. Age at onset, level and type of M protein (κ vs λ), and severity of muscle weakness were not associated with a specific outcome. CLASSIFICATION OF EVIDENCE This study provides Class IV evidence that for patients with SLONM-MGUS, HDM-SCT increases the probability of survival and functional improvement.

Inherited cavernous malformations of the central nervous system: clinical and genetic features in 19 Swiss families

Cavernous malformations (CCMs) are benign, well-circumscribed, and mulberry-like vascular malformations that may be found in the central nervous system in up to 0.5% of the population. Cavernous malformations can be sporadic or inherited. The common symptoms are epilepsy, hemorrhages, focal neurological deficits, and headaches. However, CCMs are often asymptomatic. The familiar form is associated with three gene loci, namely 7q21-q22 (CCM1), 7p13-p15 (CCM2), and 3q25.2-q27 (CCM3) and is inherited as an autosomal dominant trait with incomplete penetrance. The CCM genes are identified as Krit 1 (CCM1), MGC4607 (CCM2), and PDCD10 (CCM3). Here, we present the clinical and genetic features of CCMs in 19 Swiss families. Furthermore, surgical aspects in such families are also discussed.

Pheochromocytoma in rats with multiple endocrine neoplasia (MENX) shares gene expression patterns with human pheochromocytoma

Pheochromocytomas are rare neoplasias of neural crest origin arising from chromaffin cells of the adrenal medulla and sympathetic ganglia (extra-adrenal pheochromocytoma). Pheochromocytoma that develop in rats homozygous for a loss-of-function mutation in p27Kip1 (MENX syndrome) show a clear progression from hyperplasia to tumor, offering the possibility to gain insight into tumor pathobiology. We compared the gene-expression signatures of both adrenomedullary hyperplasia and pheochromocytoma with normal rat adrenal medulla. Hyperplasia and tumor show very similar transcriptome profiles, indicating early determination of the tumorigenic signature. Overrepresentation of developmentally regulated neural genes was a feature of the rat lesions. Quantitative RT-PCR validated the up-regulation of 11 genes, including some involved in neural development: Cdkn2a, Cdkn2c, Neurod1, Gal, Bmp7, and Phox2a. Overexpression of these genes precedes histological changes in affected adrenal glands. Their presence at early stages of tumorigenesis indicates they are not acquired during progression and may be a result of the lack of functional p27Kip1. Adrenal and extra-adrenal pheochromocytoma development clearly follows diverged molecular pathways in MENX rats. To correlate these findings to human pheochromocytoma, we studied nine genes overexpressed in the rat lesions in 46 sporadic and familial human pheochromocytomas. The expression of GAL, DGKH, BMP7, PHOX2A, L1CAM, TCTE1, EBF3, SOX4, and HASH1 was up-regulated, although with different frequencies. Immunohistochemical staining detected high L1CAM expression selectively in 27 human pheochromocytomas but not in 140 nonchromaffin neuroendocrine tumors. These studies reveal clues to the molecular pathways involved in rat and human pheochromocytoma and identify previously unexplored biomarkers for clinical use.

SDHB loss predicts malignancy in pheochromocytomas/sympathethic paragangliomas, but not through hypoxia signalling

Prediction of malignant behaviour of pheochromocytomas/sympathetic paragangliomas (PCCs/PGLs) is very difficult if not impossible on a histopathological basis. In a familial setting, it is well known that succinate dehydrogenase subunit B (SDHB)-associated PCC/PGL very often metastasise. Recently, absence of SDHB expression as measured through immunohistochemistry was shown to be an excellent indicator of the presence of an SDH germline mutation in PCC/PGL. SDHB loss is believed to lead to tumour formation by activation of hypoxia signals. To clarify the potential use of SDHB immunohistochemistry as a marker of malignancy in PCC/PGL and its association with classic hypoxia signalling we examined SDHB, hypoxia inducible factor-1 (Hif-1 ) and its targets CA-9 and GLUT-1 expression on protein level using immunohistochemistry on a tissue micro array on a series of familial and sporadic tumours of 115 patients. Survival data was available for 66 patients. SDHB protein expression was lost in the tumour tissue of 12 of 99 patients. Of those 12 patients, 5 had an SDHB germline mutation, in 4 patients no germline mutation was detected and mutational status remained unknown in parts in 3 patients. Loss of SDHB expression was not associated with increased classic hypoxia signalling as detected by Hif-1 , CA-9 or GLUT-1 staining. Loss of SDHB expression was associated with an adverse outcome. The lack of correlation of SDHB loss with classic hypoxia signals argues against the current hypoxia hypothesis in malignant PCC/PGL. We suggest SDHB protein loss as a marker of adverse outcome both in sporadic and in familial PCC/PGL.