Further, to elucidate the factors involved in the regulation of CD26 expression in MM cells, MM cell lines (KMS18, KMS26, and KMS28) were cultured under stimulation with anti-apoptotic cytokines, including IL-6, SDF-1, TNFα, APRIL, and BAFF, produced by the OCs or BMSCs in MM. The gene discussed is TNF; the disease is Miyoshi myopathy.