In vitro assessment of bone marrow endothelial colonies (CFU-En) in non-Hodgkin's lymphoma patients undergoing peripheral blood stem cell transplantation: Endothelial Colonies

The distribution and functional characteristics of in vitro bone marrow (BM) endothelial colonies (CFU-En) were studied in 70 non-Hodgkin's lymphoma (NHL) patients in different phases of the disease to explore the association between CFU-En growth and angiogenesis, and between the number of CFU-En and the presence of hematopoietic and mesenchymal progenitor cells. The mean number of CFU-En/10 6 BM mononuclear cells seen in remission patients was significantly higher than that seen in newly diagnosed patients ( P =0.04), and in normal subjects ( P =0.008). Patients with low-grade NHL in remission displayed a higher CFU-En value compared with high-grade NHL ( P =0.04). In the autograft group (40 patients), a significant reduction of CFU-En number was detected in the first 4–6 months after transplantation. In remission patients, the CFU-En number positively correlated with the incidence of BM colony-forming unit granulocyte–macrophage (CFU-GM) ( P =0.013) and CFU-multilineage (CFU-GEMM) hematopoietic colonies ( P =0.044). These in vitro data show that CFU-En numbers increase following standard-dose chemotherapy, thus providing a rationale for further investigating the effects of different cytostatic drugs on BM endothelial cells growth and function.