[Pathobiology, pathology and genetics of pulmonary hypertension: Recommendations of the Cologne Consensus Conference 2016]. / Pathobiologie, Pathologie und Genetik der pulmonalen Hypertonie: Empfehlungen der Kölner Konsensus-Konferenz 2016.

The 2015 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension (PH) are also valid for Germany. While the guidelines contain detailed recommendations regarding clinical aspects of pulmonary arterial hypertension (PAH) and other forms of PH, they contain only a relatively short paragraph on novel findings on the pathobiology, pathology, and genetics. However, these are of great importance for our understanding of this complex disease both from a clinical and scientific point of view, and they are essential for the development of novel treatment strategies. To this end, a number of current data are relevant, prompting a detailed commentary to the guidelines, and the consideration of new scientific data. In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to the pathobiology, pathology and genetics of PH. This article summarizes the results and recommendations of this working group.

[Pulmonary (Arterial) Hypertension]. / Pulmonal (arterielle) Hypertonie.

Pulmonary arterial hypertension (PAH) is a rare disease characterised by vascular remodelling of the small lung arteries leading to a decrease of the vessel lumen and eventually to occlusion. According to the current guidelines, PAH is defined by a pulmonary arterial pressure ≥ 25 mmHg, an arterial wedge pressure ≤ 15 mmHg, and an elevated pulmonary vascular resistance (PVR > 3 WU). The current pathophysiological concepts include disturbances in the production, deposition and composition of the extracellular matrix, inflammatory processes, mutations in the BMPR2 gene as well as mutations in the KCNK3 gene. During the last few years, epigenetic and genetic investigations resulted in new findings which are highly relevant for the diagnosis, prognosis and therapy of PAH. These findings could lead to the development of new, individualised therapy strategies. Currently, several phase I and phase II studies are in progress, in which promising new substances are examined.

PCK2 activation mediates an adaptive response to glucose depletion in lung cancer.

Cancer cells are reprogrammed to utilize glycolysis at high rates, which provides metabolic precursors for cell growth. Consequently, glucose levels may decrease substantially in underperfused tumor areas. Gluconeogenesis results in the generation of glucose from smaller carbon substrates such as lactate and amino acids. The key gluconeogenic enzyme, phosphoenolpyruvate carboxykinase (PEPCK), has been shown to provide metabolites for cell growth. Still, the role of gluconeogenesis in cancer is unknown. Here we show that the mitochondrial isoform of PEPCK (PCK2) is expressed and active in three lung cancer cell lines and in non-small cell lung cancer samples. PCK2 expression and activity were enhanced under low-glucose conditions. PEPCK activity was elevated threefold in lung cancer samples over normal lungs. To track the conversion of metabolites along the gluconeogenesis pathway, lung cancer cell lines were incubated with (13)C3-lactate and label enrichment in the phosphoenolpyruvate (PEP) pool was measured. Under low glucose, all three carbons from (13)C3-lactate appeared in the PEP pool, further supporting a conversion of lactate to pyruvate, via pyruvate carboxylase to oxaloacetate, and via PCK2 to phosphoenolpyruvate. PCK2 small interfering RNA and the pharmacological PEPCK inhibitor 3-mercaptopicolinate significantly enhanced glucose depletion-induced apoptosis in A549 and H23 cells, but not in H1299 cells. The growth of H23 multicellular spheroids was significantly reduced by 3-mercaptopicolinate. The results of this study suggest that lung cancer cells may utilize at least some steps of gluconeogenesis to overcome the detrimental metabolic situation during glucose deprivation and that in human lung cancers this pathway is activated in vivo.