Senescence-associated lysosomal dysfunction impairs cystine deprivation-induced lipid peroxidation and ferroptosis
Tze Mun Loo, Xiangyu Zhou, Yôko Tanaka, Sho Sugawara, S. Yamauchi, Hiroko Kawasaki, Yuta Matsuoka, Yuki Sugiura, Shinya Sakuma, Yoko Yamanishi, Satoshi Yotsumoto, Kosuke Dodo, Yoshitaka Shirasaki, Takashi Kamatani, Akiko Takahashi
Abstract
Senescent cells, characterized by irreversible cell cycle arrest and inflammatory factor secretion, promote various age-related pathologies. Senescent cells exhibit resistance to ferroptosis, a form of iron-dependent cell death; however, the underlying mechanisms remain unclear. Here, we discovered that lysosomal acidity was crucial for lipid peroxidation and ferroptosis induction by cystine deprivation. In senescent cells, lysosomal alkalinization causes the aberrant retention of ferrous iron in lysosomes, resulting in resistance to ferroptosis. Treatment with the V-ATPase activator EN6 restored lysosomal acidity and ferroptosis sensitivity in senescent cells. A similar ferroptosis resistance mechanism involving lysosomal alkalinization was observed in pancreatic cancer cell lines. EN6 treatment prevented pancreatic cancer development in xenograft and Kras mutant mouse models. Our findings reveal a link between lysosomal dysfunction and the regulation of ferroptosis, suggesting a therapeutic strategy for the treatment of age-related diseases. This study reveals that lysosomal dysfunction in senescent cells impairs lipid peroxidation and ferroptosis under cystine deprivation, uncovering a new mechanism of ferroptosis resistance linked to cellular senescence and providing a therapeutic strategy for age-related diseases.