PSMB8 was reported to be a target gene of miR‐451a in A549 lung cancer cells.27 Strong expression of PSMB8 was also reported to be correlated with increased depth of local invasion and lymph node metastasis in gastric cancer.28 Based on these reported results and our own results, we suggested that miR‐451a may act as a cancer suppressor by inhibiting the cancer promoter function of PSMB8 in PTC. This evidence concerns the gene PSMB8 and cancer.