Primary and recurrent NPC samples show differential gene expression patterns, such as kallikrein related peptidase 11 (KLK11) [60], succinate dehydrogenase subunit B (SDHB), pyruvate dehydrogenase kinase 1(PDK1) [61], replication protein A3 (RPA3) [62], short palate, lung, nasal epithelium clone1 (SPLUNC1) and mixed Lineage Leukemia 3 (MLL3) [63] as well as long noncoding RNAs [17]. Here, PDK1 is linked to nasopharyngeal carcinoma.