Epstein‐Barr virus infection induces miR‐21 in terminally differentiated malignant B cells

The association of Epstein‐Barr virus (EBV) with plasmacytoid malignancies is now well established but how the virus influences microRNA expression in such cells is not known. We have used multiple myeloma (MM) cell lines to address this issue and find that an oncomiR, miR‐21 is induced after in vitro EBV infection. The PU.1 binding site in miR‐21 promoter was essential for its activation by the virus. In accordance with its noted oncogenic functions, miR‐21 induction in EBV infected MM cells caused downregulation of p21 and an increase in cyclin D3 expression. EBV infected MM cells were highly tumorigenic in SCID mice. Given the importance of miR‐21 in plasmacytoid malignancies, our findings that EBV could further exacerbate the disease by inducing miR‐21 has interesting implications both in terms of diagnosis and future miR based therapeutical approaches for the virus associated plasmacytoid tumors.     

An update on chemotherapy for osteosarcoma

Introduction: In the early seventies chemotherapy significantly improved survival in osteosarcoma. Since then minor innovations have occurred although recent years have offered insights of clinical and scientific relevance.Areas covered: This review focuses on the most recent results of phase 3 and 2 studies. Published data or presentations at International meetings are discussed. A specific section discusses recent insights from studies supporting the hypothesis of a possible personalized chemotherapy approach.Expert opinion: Osteosarcoma is a rare tumor and any effort should be made to improve the level of International collaboration. The MAP (methotrexate, doxorubicin and cisplatin) regimen has become the treatment of choice. Poor pathological response to primary chemotherapy is confirmed as a predictive factor of survival and, presently with the available drugs, it is not recommended to intensify or change post-operative treatment on the basis of pathological response to primary chemotherapy. The genomic complexity and the heterogeneity of osteosarcoma makes active and effective molecularly targeted therapies unlikely to be available in the near future. A relation between pharmacogenetic profile and chemotherapy toxicity and prognosis has been reported. The new frontier for clinical research in osteosarcoma is to optimize the use of the active drugs available by personalizing chemotherapy treatment.     

Intravital imaging reveals p53-dependent cancer cell death induced by phototherapy via calcium signaling

One challenge in biology is signal transduction monitoring in a physiological context. Intravital imaging techniques are revolutionizing our understanding of tumor and host cell behaviors in the tumor environment. However, these deep tissue imaging techniques have not yet been adopted to investigate the second messenger calcium (Ca²⁺). In the present study, we established conditions that allow the in vivo detection of Ca²⁺ signaling in three-dimensional tumor masses in mouse models. By combining intravital imaging and a skinfold chamber technique, we determined the ability of photodynamic cancer therapy to induce an increase in intracellular Ca²⁺ concentrations and, consequently, an increase in cell death in a p53-dependent pathway.     

2D-DIGE proteomic analysis identifies new potential therapeutic targets for adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare aggressive tumor with poor prognosis when metastatic at diagnosis. The tumor biology is still mostly unclear, justifying the limited specificity and efficacy of the anti-cancer drugs currently available. This study reports the first proteomic analysis of ACC by using two-dimensional-differential-in-gel-electrophoresis (2D-DIGE) to evaluate a differential protein expression profile between adrenocortical carcinoma and normal adrenal. Mass spectrometry, associated with 2D-DIGE analysis of carcinomas and normal adrenals, identified 22 proteins in 27 differentially expressed 2D spots, mostly overexpressed in ACC. Gene ontology analysis revealed that most of the proteins concurs towards a metabolic shift, called the Warburg effect, in adrenocortical cancer. The differential expression was validated by Western blot for Aldehyde-dehydrogenase-6-A1,Transferrin, Fascin-1,Lamin A/C,Adenylate-cyclase-associated-protein-1 and Ferredoxin-reductase. Moreover, immunohistochemistry performed on paraffin-embedded ACC and normal adrenal specimens confirmed marked positive staining for all 6 proteins diffusely expressed by neoplastic cells, compared with normal adrenal cortex.In conclusion, our preliminary findings reveal a different proteomic profile in adrenocortical carcinoma compared with normal adrenal cortex characterized by overexpression of mainly metabolic enzymes, thus suggesting the Warburg effect also occurs in ACC. These proteins may represent promising novel ACC biomarkers and potential therapeutic targets if validated in larger cohorts of patients.     

Adult-onset leukodystrophies from respiratory chain disorders: do they exist?

Respiratory chain disorders (RCDs) have been included in the differential diagnosis of adult-onset leukodystrophies. Here, we first report a 32-year-old female with an atypical, adult-onset, non-syndromic RCD due to a mitochondrial DNA deletion and manifesting as complicated ataxia. A ‘leukodystrophic’ pattern was found on brain MRI, but it was neither isolated nor predominant because of the presence of overt basal ganglia and infratentorial lesions, which led us to the proper diagnosis. Subsequently, we evaluated our series of patients with RCDs in order to verify whether a ‘leukodystrophic’ pattern with little or no involvement of deep grey structures and brainstem may be found in adult-onset RCDs, as reported in children. Among 52 patients with adult-onset RCDs, no case with a ‘leukodystrophic’ pattern was found, apart from three cases with a classical phenotype of mitochondrial neurogastrointestinal encephalopathy. In addition, no case of RCDs was found among six cases of adult-onset leukodystrophy of unknown origin and at least one feature suggestive of mitochondrial disease. The review of the literature was in agreement with these findings. Thus, we provide evidence that, unlike in children, RCDs should not be included in the differential diagnosis of adult-onset leukodystrophies, except when there are additional MRI findings or clinical features which unequivocally point towards a mitochondrial disorder.     

Erythropoietin and the heart: facts and perspectives

EPO (erythropoietin) has long been identified as a primary regulator of erythropoiesis. Subsequently, EPO has been recognized as playing a role in a broad variety of processes in cardiovascular pathophysiology. In particular, the tight interactions of EPO with the nitric oxide pathway, apoptosis, ischaemia, cell proliferation and platelet activation appear of great interest. Although enhanced EPO synthesis is viewed as an appropriate compensatory mechanism in the cardio-renal syndrome, which features CHF (congestive heart failure) and CRF (chronic renal failure), maladaptative excessive EPO synthesis in the advanced stages of these diseases appears to be predictive of higher mortality. Clinical trials based on the use of EPO in both heart and renal failure have so far produced contradictory results, whereas treatment targeted to restore low Hb levels appears rational and is supported by regulatory authorities. New areas for therapeutic use of EPO, such as acute coronary syndromes, are under investigation, and they are discussed in the present review together with other clinical applications in cardiovascular diseases. The revisited concept of a potential use of endogenous EPO levels as a predictor of CHF severity, as well as in the monitoring of responses to treatment, deserves appropriate investigation, as this may identify EPO as a useful biomarker in the clinical management of cardiovascular diseases.     

Diagnostic accuracy of the double-contrast enema for colonic polyps in patients with or without diverticular disease

The accuracy of the double-contrast enema for the diagnosis of polypoid lesions in the presence or absence of diverticula was evaluated by retrospectively reviewing the medical records of 202 patients subjected to examination and endoscopy. Analysis of the data on 215 polypoid lesions showed that (a) the diagnostic accuracy of the examination is not affected significantly by the presence of diverticula; (b) the sensitivity of the examination is highly dependent on the size of the polyps (smaller or larger than 0.5 cm) but not on the form (sessile or pedunculated); and (c) the positive predictive value is higher in patients without diverticula. The doublecontrast enema was confirmed to be a valid method for the diagnosis of polypoid lesions.