The qRT-PCR results showed that BM-MSCs on incubation with NPC exosomes showed a significant increase in the mRNA levels of ACAN, SOX-9, COL2A1, HIF-1α, CA12 and KRT19 compared with BM-MSCs cultured alone (Fig. 5a). The gene discussed is ACAN; the disease is nasopharyngeal carcinoma.