Fig. 7: The NRG1/PDGFC positive feedback loop between CAFs and BC cells promotes PTX resistance in BC.

NRG1 derived from CAFs promotes ferroptosis escape in BC cells through the activation of the AKT/mTOR signaling pathway, thereby promoting PTX resistance in BC cells. Meanwhile, activation of the AKT/mTOR signaling pathway induces high expression of PDGFC, and BC cells release PDGFC to activate fibroblasts and further release NRG1, ultimately forming the NRG1/PDGFC positive feedback loop.