Previous studies have implicated the important role of mesenchymal stem/stromal cells (MSCs) within tumor microenvironment (TME) in the pathogenesis and progression of
nasopharyngeal carcinoma (NPC), but the potential mechanisms are still unclear. Herein, we showed that an elevated
IL-6 level was positively correlated with elevated expression of CD73 in TME of NPC. NPC specimens with an IL-6highCD73high phenotype showed higher expression levels of gp80, gp130, p-STAT3, MMP-9 and α-SMA, and clinically, a poorer prognosis than those with an IL-6lowCD73low phenotype. We found that stimulation with
conditioned media derived from
IL-6 gene knocked out MSC (MSCIL6KO-CM) down-regulated the expression of CD73,
IL-6, gp80, p-STAT3, and proliferative cell
nuclear antigen (
PCNA) in CNE-2 NPC cells. Meanwhile, NPC cells co-cultured with MSCIL6KO-CM were more sensitive to
cisplatin than those co-cultured with MSC-CM. Additionally, MSC-derived
IL-6 transcriptionally upregulated CD73 expression via activating STAT3 signaling pathway in NPC cells. In summary, our findings suggest that MSCs promote NPC progression and chemoresistance by upregulation of CD73 expression via activating STAT3 signaling pathway.