In order to further clarify the relationship between the expression of the miRNAs and PTBP1, we examined whether brain-specific MIR137 and muscle-specific MIR206 could directly bind to PTBP1. We selected glioblastoma (GBM) cell lines, i.e., U-251 and U-87, in the case of brain-specific MIR137 and rhabdomyosarcoma (RMS) RD and KYM-1 cell lines in the case of muscle-specific MIR206. As a result, the protein expression levels of PTBP1 were downregulated in these miRNA-treated cells tested. The gene discussed is MIR206; the disease is rhabdomyosarcoma.