SRSF1 and nasopharyngeal carcinoma: Our study demonstrated that circPVT1 was positively co-regulated by c-Myc and SRSF1 in NPC cells, and on the other hand circPVT1 inhibited the ubiquitin-mediated degradation of c-Myc by binding to β-TrCP, which blocked the interaction between the ubiquitin E3 ligase β-TrCP and its target c-Myc.