Therefore, clinical research performed by a collaboration of medical institutions examined the expression status of LMP2/β1i in 74 cases with normal myometrium, uterine leiomyoma, uLMS, and other uterine mesenchymal tumor tissues obtained from pathological files by immunohistochemical (IHC) staining using an antihuman LMP2/β1i monoclonal antibody [16,17]. This evidence concerns the gene PSMB9 and uterine corpus leiomyoma.