Distinct transcriptional profiles in plasma exosomes associated with recurrence of nasopharyngeal carcinoma patients with standard treatment

6534 Background: Nasopharyngeal carcinoma (NPC) is endemic with a high prevalence in Southern China, Asia,cetuximab and North Africa. Exosomes are small vesicles containing a wide range of functional proteins, mRNA and miRNA. In the progression of NPC, the tumor cells constantly release exosomes into the surrounding environment and also into the circulating blood. The aim of this study was to explore the association between RNA expression in plasma exosomes and prognosis of NPC patients after standard treatment. Methods: In this retrospective study, a total of 25 eligible NPC patients were included: 12 patients in the recurrence (R) subgroup and 13 patients in the no recurrence (NR) subgroup. RNA was extracted from the exosomes of plasma specimens which were collected at West China Hospital, Sichuan University. Gene expression profiles were conducted by using the RNA-sequencing platform. The DESeq2 package was used to analyze the differentially expressed genes (DEGs) between R and NR subgroups. The gene set variance analysis (GSVA) was performed to explore C5 gene sets enrichment related to the recurrence after standard treatment. Results: We observed 332 DEGs between R and NR subgroups, which include 125 up-regulated and 207 down-regulated genes (R vs. NR,∣log2fold change∣>1, p