Extracellular Acidification Induces Lysosomal Dysregulation

Many invasive cancers emerge through a years-long process of somatic evolution, characterized by an accumulation of heritable genetic and epigenetic changes and the emergence of increasingly aggressive clonal populations. In solid tumors, such as breast ductal carcinoma, the extracellular environment for cells within the nascent tumor is harsh and imposes different types of stress on cells, such as hypoxia, nutrient deprivation, and cytokine inflammation. Acidosis is a constant stressor of most cancer cells due to its production through fermentation of glucose to lactic acid in hypoxic or normoxic regions (Warburg effect). Over a short period of time, acid stress can have a profound effect on the function of lysosomes within the cells exposed to this environment, and after long term exposure, lysosomal function of the cancer cells can become completely dysregulated. Whether this dysregulation is due to an epigenetic change or evolutionary selection has yet to be determined, but understanding the mechanisms behind this dysregulation could identify therapeutic opportunities.

Automated summary

Invasive cancers usually develop over a long period through somatic evolution, with heritable genetic and epigenetic changes leading to the emergence of aggressive clonal populations. The extracellular environment in solid tumors imposes various stresses on cells, such as hypoxia, nutrient deprivation, and cytokine inflammation. Acidosis, a common stressor for cancer cells, affects lysosomal function over time, potentially leading to dysregulation that could be targeted for therapeutic interventions.