Abstract
Tumor progression and therapy resistance are formed not only by cancer cell intrinsic mechanisms but also by dynamic interactions with the surrounding tumor stroma. Metabolic regulation is central to these interactions, with lipid pathways emerging as critical determinants of cell fate. A growing concept is the phosphatidylcholine ferroptosis axis, which functions as a metabolic checkpoint linking membrane remodeling, oxidative stress, and tumor stroma communication. Phosphatidylcholine, the most abundant phospholipid in mammalian membranes, is primarily synthesized through the Kennedy pathway under the control of choline kinase alpha. Enhanced phosphatidylcholine synthesis alters membrane architecture and generates substrates for lipid remodeling. These changes regulate susceptibility to ferroptosis, a regulated form of cell death driven by iron-dependent lipid peroxidation. Remodeling by enzymes such as lysophosphatidylcholine acyltransferases and phospholipase A2 influences polyunsaturated fatty acid incorporation into membranes, thereby determining the pool of lipids prone to oxidative damage. Phosphatidylcholine metabolism extends beyond cancer cells to the tumor microenvironment. Cancer-associated fibroblasts can supply phosphatidylcholine derived from metabolites that buffer tumor cells against ferroptosis, while altered phosphatidylcholine dynamics modulate macrophage and T cell activity, influencing immune surveillance and inflammatory tone. Through these mechanisms, the phosphatidylcholine-ferroptosis axis integrates metabolic control of cell death with stromal regulation of tumor growth and resistance. Therapeutically, targeting phosphatidylcholine synthesis and remodeling combined with ferroptosis inducers or glutathione peroxidase 4 inhibitors could sensitize tumors to oxidative cell death while reprogramming stromal elements toward anti-tumor activity. This places the phosphatidylcholine ferroptosis axis as a promising target for combination therapies designed to disrupt tumor stroma crosstalk and improve clinical outcomes.