Compared to NP460hTert which is commonly used as a representative pre-malignant NPE cell line, seven NPC cell lines (CNE1, CNE2, C666-1, HONE1, SUNE1, TW01 and TW04) showed reduced levels of MAOA at both mRNA and protein levels (Fig. 1B). The gene discussed is MAOA; the disease is nasopharyngeal carcinoma.