PTGDR and nasopharyngeal carcinoma: Previously, lncRNA AFAP1-AS1 was reported to act as a competing endogenous RNA of miR-423-5p to facilitate nasopharyngeal carcinoma metastasis [34]; while Yin et al. demonstrated that AFAP1-AS1 is associated with poor survival of patients with non-small cell lung cancer, and enhances cell proliferation via inhibition of p21 expression [35].