SRGN and cancer: 16 Subsequently, we further showed that serglycin was an independent marker of distant metastases in NPC.21 In another study comparing the genomic expression profiles of NPCs versus non-cancerous naspharyngeal tissues, we found that the ECM remodeling pathway was the most significantly changed signaling pathway in NPC tissues.20 Our findings suggest that serglycin proteoglycan acts as microenviroment ECM, where NPC cancer stem cells (CSCs) reside, and may have an important role in ECM remodeling responsible for NPC progression.