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Proton pump inhibitors are widely used throughout the world for the treatment of gastrointestinal disorders that are related to acid secretion, such as peptic ulcer disease and dyspepsia. Another common indication for proton pump inhibitors is stress ulcer prophylaxis. Proton pump inhibitors have proven efficacy for the treatment of acid-related gastrointestinal disorders, but there is concern that their use may be associated with the development of significant complications, such as fractures, Clostridium difficile infection, acute kidney injury, chronic kidney disease, and hypomagnesemia. Proton pump inhibitors are overused in the hospital setting, both for stress ulcer prophylaxis and gastrointestinal bleeding, and then they are often inappropriately continued after discharge from the hospital. This narrative review article outlines the evidence surrounding appropriate proton pump inhibitor use for stress ulcer prophylaxis and peptic ulcer bleeding.

Gliomas are primary brain tumors with a complex biology characterized by antigenic and genomic heterogeneity and a propensity for invasion into normal brain tissue. High grade glioma cells possess a voltage-independent, amiloride-inhibitable, inward Na+ current. This current does not exist in normal astrocytes or low grade tumor cells. Inhibition of this conductance decreases glioma growth and cell migration making it a potential therapeutic target. Our previous results have shown that the acid-sensing ion channels (ASICs), members of the epithelial Na+ channel (ENaC)/degenerin (DEG) family of ion channels are part of this current pathway. We hypothesized that one member of the ENaC/DEG family, ASIC2, is retained intracellularly and that it is the lack of functional expression of ASIC2 at the cell surface that results in hyperactivity of this conductance in high grade gliomas. In this study we show that the chemical chaperone, glycerol, and the transcriptional regulator, sodium 4-phenylbutyrate, inhibit the constitutively activated inward current and reduce cell growth and migration in glioblastoma multiforme. The results suggest that these compounds induce the movement of ASIC2 to the plasma membrane, and once there, the basally active inward current characteristic of glioma cells is abolished by inherent negative regulatory mechanisms. This in turn compromises the ability of the glioma cell to migrate and proliferate. These results support the hypothesis that the conductance pathway in high grade glioma cells is comprised of ENaC/DEG subunits and that abolishing this channel activity promotes a reversion of a high grade glioma cell to a phenotype resembling that of normal astrocytes.