HVCN1 and gastric cancer: When discussing natural protein proton channels, of central importance is the knowledge of how proton transfer reactions can be used in pharmacology for threatening certain diseases, such as preventing brain damage from ischemic stroke [77,78], cancer [79] by inhibiting the voltage-gated proton channel Hv1, chronic gastritis, duodenal ulcers and, stomach cancer [80,81] by disabling the Urel channel of Helicobacter pylori which transports urea and maintains the proton gradient across the bacterial plasma, and the list can further continue.