Cellular acidosis buffering

Cellular acidosis buffering refers to the physiological mechanisms employed by cells to maintain pH homeostasis, a critical requirement for metabolic activity and protein stability. This process is not a single molecular entity but a coordinated system involving enzymes like carbonic anhydrases (notably CA IX and XII), ion exchangers such as sodium-hydrogen exchanger 1 (NHE1), and transporters like monocarboxylate transporters (MCT1, MCT4) and bicarbonate transporters (SLC4 family) [PMID: 23732726]. In the context of the tumor microenvironment, cancer cells utilize these buffering systems to export excess protons and lactate generated by high glycolytic flux, resulting in an alkaline intracellular environment and an acidic extracellular space [PMID: 28775351]. This "pH inversion" promotes tumor progression, metastasis, and resistance to therapy. Pharmacological targeting of these buffering components, such as with CA IX inhibitors or MCT inhibitors, aims to disrupt this balance to selectively kill cancer cells [PMID: 21358637]. However, the ubiquity of pH regulation mechanisms in healthy tissues presents significant challenges for achieving therapeutic selectivity and avoiding systemic side effects [PMID: 24560959].

Other names

pH regulationIntracellular pH bufferingAcid-base homeostasisProton bufferingTumor acidity regulation

Disruption of pH homeostasis via inhibition of proton/bicarbonate transporters or carbonic anhydrase enzymes to collapse the transmembrane pH gradient.