FLT4 and vascular neoplasm: In all these cases, MAML1 was coamplified with FLT4. To confirm that MAML1 may be a “driver” gene of the 5q35.3 amplicon, we have assessed its mRNA by qRT-PCR (3 AS cases with MAML1 amplification, 17 AS cases without MAML1 amplification, and 2 other vascular tumors) and protein expression by Western blotting (one case with MAML1 amplification, four AS cases without MAML1 amplification and the SKBR3 cell line).