HOX11 and HOX11L2 RT-PCR quantification. RQ-PCR quantification of HOX11 (▪) and HOX11L2 (□) transcripts from controls (upper panel) and T-ALLs (lower panel). Controls include 6 normal peripheral mononuclear cell (PBL), 9 bone marrow (BM) and 3 thymi, 5 acute myeloid leukemias (AMLs), and 7-T and 8-B lymphoid and 4 myeloid (My) cell lines, as indicated. Amplified transcripts were normalized for RNA quality using the ABL housekeeping gene and were expressed as equivalent plasmid copy numbers on a logarithmic scale. Samples expressing more than 10⁴ copies of HOX11 or HOX11L2 were classified as positive (bold line). Six adult and 1 adolescent T-ALLs expressed 1 to 2 log lower levels of HOX11, 3 in conjunction with HOX11L2 expression. T-ALLs demonstrating fewer than 100 copies of HOX11 and HOX11L2 are not shown.