Linking hyperosmotic stress and apoptotic sensitivity

Abstract

How hypertonic stress induces or sensitizes to cell death signals is incompletely understood and rarely studied in cancer. Heimer et al. demonstrate that hypertonic environments neutralize the antiapoptotic Bcl‐2 family member Mcl‐1 by upregulating its antagonist Noxa. Consequently, hypertonically stressed head and neck squamous cell carcinoma cells rely solely on Bcl‐xL for survival and succumb to apoptosis when challenged by pharmacological Bcl‐xL inhibition. Similar findings were reported in colorectal cancer cells in related manuscripts, suggesting that a common and conserved mechanistic link might exist between hyperosmotic stress and cellular sensitisation to apoptosis.