The hypoxia-inducible factor (HIF) family of transcription factors directs a coordinated cellular response to hypoxia that includes the transcriptional regulation of a number of metabolic enzymes. Chuvash polycythemia (CP) is an autosomal recessive human disorder in which the regulatory degradation of HIF is impaired, resulting in elevated levels of HIF at normal oxygen tensions. Apart from the polycythemia, CP patients have marked abnormalities of cardiopulmonary function. No studies of integrated metabolic function have been reported. Here we describe the response of these patients to a series of metabolic stresses: exercise of a large muscle mass on a cycle ergometer, exercise of a small muscle mass (calf muscle) which allowed noninvasive in vivo assessments of muscle metabolism using 31 P magnetic resonance spectroscopy, and a standard meal tolerance test. During exercise, CP patients had early and marked phosphocreatine depletion and acidosis in skeletal muscle, greater accumulation of lactate in blood, and reduced maximum exercise capacities. Muscle biopsy specimens from CP patients showed elevated levels of transcript for pyruvate dehydrogenase kinase, phosphofructokinase, and muscle pyruvate kinase. In cell culture, a range of experimental manipulations have been used to study the effects of HIF on cellular metabolism. However, these approaches provide no potential to investigate integrated responses at the level of the whole organism. Although CP is relatively subtle disorder, our study now reveals a striking regulatory role for HIF on metabolism during exercise in humans. These findings have significant implications for the development of therapeutic approaches targeting the HIF pathway.exercise | lactate | glycolysis | Chuvash polycythemia | von Hippel-Lindau

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To complete the existing treatment guidelines for all tumor types, ESMO organizes consensus conferences to better clarify open issues in each disease. In this setting, a consensus conference on the management of lymphoma was held on 18 June 2011 in Lugano, immediately after the end of the 11th International Conference on Malignant Lymphoma. The consensus conference convened ∼45 experts from all around Europe and selected six lymphoma entities to be addressed; for each of them three to five open questions were to be discussed by the experts. For each question, a recommendation should be given by the panel, supported by the strength of the recommendation based on the level of evidence. This consensus report focuses on the three most common lymphoproliferative malignancies: diffuse large B-cell lymphoma, follicular lymphoma and chronic lymphocytic leukemia. A second report will concentrate on mantle cell lymphoma, marginal zone lymphoma and T-cell lymphomas.