GPX4 and nasopharyngeal carcinoma: To explore whether the reduced ferroptosis sensitivity of NPC cells caused by EBV infection depends on the upregulated expression of GPX4, we used two specific shRNAs to knockdown endogenous GPX4 (Fig. 4C) and found that GPX4 knockdown rendered EBV-positive cells more susceptible to ferroptosis induced by cystine starvation (Fig. 4D).