SREBF1 and nasopharyngeal carcinoma: In NPC xenografts (C17, X2117, and C15), western blotting analysis revealed higher levels of the precursor and mature forms of SREBP1 and FASN in the LMP1‐positive X2117 and C15 xenografts than in the LMP1‐negative C17 xenograft and EBV‐negative non‐malignant NP69 nasopharyngeal epithelial cell line (Figure 2A).