PCR analysis of a panel of 18 permanent human tumor cell lines consisting of 6 different tumor types including four Ewing sarcoma cell lines (CADO-ES-1, STA-ET-1, STA-ET-2.1, and VH-64), four neuroblastoma cell lines (IMR5, KCN, SHEP-SF, and SH-SY5Y), two medulloblastoma cell lines (MNNG-HOS, UW228.2), two rhabdomyosarcoma cell lines (RD, RH30), two human acute lymphoblastic leukemia (ALL) T-cell lines (CCRF-CEM and MOLT-4), the human B-cell precursor ALL cell line REH, and the human acute myeloid leukemia cell line HL-60 showed that these cells do not express any OCT subtype. This evidence concerns the gene PLXNA2 and acute lymphoblastic leukemia.