MOMP is the point-of-no-return decision step of intrinsic apoptosis. It is the event in which the mitochondrial outer membrane becomes permeable, allowing release of pro-death factors that irreversibly commit a cell to die. Cancer progression is characterized by systematic suppression, buffering, or decoupling of MOMP from lethal execution.
MOMP occurs when BAX and/or BAK oligomerize in the mitochondrial outer membrane, forming pores that release:
-Cytochrome c → apoptosome → caspase-9
-Smac/DIABLO → IAP neutralization
-Other apoptogenic factors (e.g., Omi/HtrA2)
Once sufficient mitochondria undergo MOMP, cell death is inevitable (even if caspases are later inhibited).
Redox, Metabolism, and MOMP (Critical)
-High xCT / GSH → suppress mitochondrial ROS → MOMP ↓
-Autophagic flux → removes damaged mitochondria → MOMP ↓
-Pro-oxidant overload → mitochondrial dysfunction → MOMP ↑
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