Melanoma incidence and exposure to angiotensin-converting enzyme inhibitors and angiotensin receptor blockers

A reduced incidence of nonmelanoma skin cancer among users of angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARb) has been reported. A similar effect is suggested for cutaneous melanoma. We aimed to investigate the possible association between use of ACEi and ARb and the risk of cutaneous melanoma. A general population-based case control study with the PHARMO database, containing drug-dispensing records from community pharmacies and the national pathology database (PALGA) was conducted. Cases were patients with a primary cutaneous melanoma between January 1st 1991 and December 14th 2004, aged ≥18 years and having ≥3 years of follow-up prior to diagnosis. Finally, 1272 cases and 6520 matched controls were included. Multivariable conditional logistic regression showed no statistically significant associations between the incidence of melanoma and the use of ACEi (adjusted OR = 1.0, 95%CI: 0.8–1.3) or ARb (adjusted OR = 1.0, 95%CI: 0.7–1.5). Thus, in this study, the use of ACEi or ARb does not seem to protect against the development of cutaneous melanoma. However, we cannot exclude an association between ACEi and ARb exposure and an increased or decreased incidence of cutaneous melanoma.     

Non-invasive imaging of mouse hepatitis coronavirus infection reveals determinants of viral replication and spread in vivo

Bioluminescence imaging (BLI) is a powerful new method to study virus dissemination in the live animal. Here we used this method to monitor the spatial and temporal progression of mouse hepatitis coronavirus (MHV) infection in mice using luciferase-expressing viruses. Upon intranasal inoculation, virus replication could initially be observed in the nasal cavity and the cervical lymph nodes, after which the infection spread to the brain and frequently to the eyes. The kinetics of virus spread to and clearance from the brain appeared to depend on the inoculation dose. After intraperitoneal inoculation, virus replication was predominantly observed in the liver and occasionally in the intestines, but interestingly also in the tail and paws. BLI thus elucidated new anatomic locations of virus replication. Furthermore, MHV dissemination was shown to be critically depended on the viral spike protein, but also on the mouse strain used. Widespread dissemination was observed in mice lacking a functional type I interferon response. The importance of the type I interferon system in limiting viral spread was also demonstrated by the administration of type I interferons to mice. Our results provide new insights in coronavirus pathogenesis and demonstrate the potential of BLI to study coronavirus–host interactions in vivo .     

Human Golgi Antiapoptotic Protein Modulates Intracellular Calcium Fluxes

Golgi antiapoptotic protein (GAAP) is a novel regulator of cell death that is highly conserved in eukaryotes and present in some poxviruses, but its molecular mechanism is unknown. Given that alterations in intracellular Ca²⁺ homeostasis play an important role in determining cell sensitivity to apoptosis, we investigated if GAAP affected Ca²⁺ signaling. Overexpression of human (h)-GAAP suppressed staurosporine-induced, capacitative Ca²⁺ influx from the extracellular space. In addition, it reduced histamine-induced Ca²⁺ release from intracellular stores through inositol trisphosphate receptors. h-GAAP not only decreased the magnitude of the histamine-induced Ca²⁺ fluxes from stores to cytosol and mitochondrial matrices, but it also reduced the induction and frequency of oscillatory changes in cytosolic Ca²⁺. Overexpression of h-GAAP lowered the Ca²⁺ content of the intracellular stores and decreased the efficacy of IP₃, providing possible explanations for the observed results. Opposite effects were obtained when h-GAAP was knocked down by siRNA. Thus, our data demonstrate that h-GAAP modulates intracellular Ca²⁺ fluxes induced by both physiological and apoptotic stimuli.     

Evaluation of Mitotic Activity Index in Breast Cancer Using Whole Slide Digital Images

Introduction

Mitotic Activity Index (MAI) is an important independent prognostic factor and an integral part of the breast cancer grading system. Thus, correct estimation of this prognostically relevant feature is essential for guiding treatment decision and assessing patient prognosis.The aim of this study was to validate the use of high resolution Whole Slide Images (WSI) in estimating MAI in breast cancer specimens.

Methods

MAI was evaluated in 100 consecutive breast cancer specimens by three observers on two occasions, microscopically and on WSI with a wash out period of 4 months. MAI was also translated to mitotic scores as in grading. Inter- and intra-observer agreement between microscopic and digital MAI counts and scores was measured.

Results

Almost perfect inter-observer agreements were obtained from counting MAI using a conventional microscope (intra-class correlation coefficient (ICCC) 0.879) as well as on WSI (ICCC 0.924). K coefficients reflected good inter-observer agreements among observers'' microscopic mitotic scores (average kappa 0.642). Comparable results were also observed among digital mitotic scores (average kappa 0.635). There was strong to perfect intra-observer agreements between MAI counts and mitotic scores for the two diagnostic modalities (ICCC 0.716–0.863, kappa 0.506–0.617). There were no significant differences in mitotic scores using both diagnostic modalities.

Conclusion

Scoring mitoses using WSI in breast cancer seems to be just as reliable and reproducible as when using a microscope. Further development of software and image quality will definitely encourage the use of WSI in routine pathology practice.     

Altered Dihydropyrimidine Dehydrogenase Activity Associated with Mild Toxicity in Patients Treated with 5-Fluorouracil Containing Chemotherapy

Dihydropyrimidine dehydrogenase (DPD) plays a pivotal role in the metabolism of 5-fluorouracil (5FU). In patients treated with capecitabine or 5FU combined with other chemotherapeutic drugs, DPD activity in peripheral blood mononuclear cells was increased in patients experiencing grade I/II neutropenia. In contrast, decreased DPD activity proved to be associated with grade I/II dermatological toxicity, including hand-foot syndrome. Thus, patients with a low-normal or high-normal DPD activity proved to be at risk of developing mild toxicity upon treatment with 5FU-based chemotherapy, demonstrating the important role of DPD in the etiology of toxicity associated with 5FU and the catabolites of 5FU.     

Hyperferritinaemia in Dengue Virus Infected Patients Is Associated with Immune Activation and Coagulation Disturbances

Background

During a dengue outbreak on the Caribbean island Aruba, highly elevated levels of ferritin were detected in dengue virus infected patients. Ferritin is an acute-phase reactant and hyperferritinaemia is a hallmark of diseases caused by extensive immune activation, such as haemophagocytic lymphohistiocytosis. The aim of this study was to investigate whether hyperferritinaemia in dengue patients was associated with clinical markers of extensive immune activation and coagulation disturbances.

Methodology/Principal Findings

Levels of ferritin, standard laboratory markers, sIL-2R, IL-18 and coagulation and fibrinolytic markers were determined in samples from patients with uncomplicated dengue in Aruba. Levels of ferritin were significantly increased in dengue patients compared to patients with other febrile illnesses. Moreover, levels of ferritin associated significantly with the occurrence of viraemia. Hyperferritinaemia was also significantly associated with thrombocytopenia, elevated liver enzymes and coagulation disturbances. The results were validated in a cohort of dengue virus infected patients in Brazil. In this cohort levels of ferritin and cytokine profiles were determined. Increased levels of ferritin in dengue virus infected patients in Brazil were associated with disease severity and a pro-inflammatory cytokine profile.

Conclusions/Significance

Altogether, we provide evidence that ferritin can be used as a clinical marker to discriminate between dengue and other febrile illnesses. The occurrence of hyperferritinaemia in dengue virus infected patients is indicative for highly active disease resulting in immune activation and coagulation disturbances. Therefore, we recommend that patients with hyperferritinaemia are monitored carefully.     

Altered dihydropyrimidine dehydrogenase activity associated with mild toxicity in patients treated with 5-fluorouracil containing chemotherapy

Dihydropyrimidine dehydrogenase (DPD) plays a pivotal role in the metabolism of 5-fluorouracil (5FU). In patients treated with capecitabine or 5FU combined with other chemotherapeutic drugs, DPD activity in peripheral blood mononuclear cells was increased in patients experiencing grade I/II neutropenia. In contrast, decreased DPD activity proved to be associated with grade I/II dermatological toxicity, including hand-foot syndrome. Thus, patients with a low-normal or high-normal DPD activity proved to be at risk of developing mild toxicity upon treatment with 5FU-based chemotherapy, demonstrating the important role of DPD in the etiology of toxicity associated with 5FU and the catabolites of 5FU.     

Decreased agonist-stimulated mitochondrial ATP production caused by a pathological reduction in endoplasmic reticulum calcium content in human complex I deficiency

Although a large number of mutations causing malfunction of complex I (NADH:ubiquinone oxidoreductase) of the OXPHOS system is now known, their cell biological consequences remain obscure. We previously showed that the bradykinin (Bk)-induced increase in mitochondrial [ATP] ([ATP](M)) is significantly reduced in primary skin fibroblasts from a patient with an isolated complex I deficiency. The present work addresses the mechanism(s) underlying this impaired response. Luminometry of fibroblasts from 6 healthy subjects and 14 genetically characterized patients expressing mitochondria targeted luciferase revealed that the Bk-induced increase in [ATP](M) was significantly, but to a variable degree, decreased in 10 patients. The same variation was observed for the increases in mitochondrial [Ca(2+)] ([Ca(2+)](M)), measured with mitochondria targeted aequorin, and cytosolic [Ca(2+)] ([Ca(2+)](C)), measured with fura-2, and for the Ca(2+) content of the endoplasmic reticulum (ER), calculated from the increase in [Ca(2+)](C) evoked by thapsigargin, an inhibitor of the ER Ca(2+) ATPase. Regression analysis revealed that the increase in [ATP](M) was directly proportional to the increases in [Ca(2+)](C) and [Ca(2+)](M) and to the ER Ca(2+) content. Our findings provide evidence that a pathological reduction in ER Ca(2+) content is the direct cause of the impaired Bk-induced increase in [ATP](M) in human complex I deficiency.     

Porcine endogenous retrovirus transmission characteristics of galactose alpha1-3 galactose-deficient pig cells

Galactose alpha1-3 galactose (Gal) trisaccharides are present on the surface of wild-type pig cells, as well as on viruses particles produced from such cells. The recognition of Gal sugars by natural anti-Gal antibodies (NAb) in human and Old World primate serum can cause the lysis of the particles via complement-dependent mechanisms and has therefore been proposed as an important antiviral mechanism. Recently, pigs have been generated that possess disrupted galactosyl-transferase (GGTA1) genes. The cells of these pigs do not express Gal sugars on their surface, i.e., are Gal null. Concerns have been raised that the risk of virus transmission from such pigs may be increased due to the absence of the Gal sugars. We investigated the sensitivity of porcine endogenous retrovirus (PERV) produced from Gal-null and Gal-positive pig cells to inactivation by purified NAb and human serum. PERV produced in Gal-null pig cells was resistant to inactivation by either NAb or human serum. In contrast, although Gal-positive PERV particles were sensitive to inactivation by NAb and human serum, they required markedly higher concentrations of NAb for inactivation compared to the Gal-positive cells from which they were produced. Complete inactivation of Gal-positive PERV particles was not achievable despite the use of high levels of NAb, indicating that NAb-mediated inactivation of cell-free PERV particles is an inefficient process.