FSTL1 and nasopharyngeal carcinoma: To identify the methylation status of the FSTL1 promoter, we performed methylation-specific PCR (MSP) in 6 NPC cell lines (CNE1, CNE2, HONE1, C666-1, HNE1 and TW03), 35 NPC biopsies and 12 NNE samples.