MRC2 and histiocytoma: The U937 myeloid leukemia, the NB-4 acute promyelocytic leukemia, the THP-1 monocytic leukemia, the HT1080 fibrosarcoma, the GCT (giant cell tumor) fibrous histiocytoma, the RD rhabdomyosarcoma, the KNS42 glioblastoma, the HS683 glioblastoma and U373 MG glioblastoma cell lines were all found to express uPARAP by Western blotting (Figure 1A).