Detection Of Endothelial Progenitor Cells And Microvessel Density In Acute Leukemia And Its Clinical Significance

[Objectives] To detect the count of EPCs both in peripheral blood (PB) and bone marrow (BM) and microvessel density(MVD) in bone marrow of acute leukemia (AL) patients; and to study the relationship between absolute counting of EPCs in BM and MVD; and to explore their clinical significance in AL disease, and new ideas for leukemia treatment.[Methods] There were66adult acute leukemia patients who were initial treatment,43patients of them were received treatment and the changes of EPCs were observed before and after treatment. EPCs count were quantified by flow cytometry procedures with10benign hemopathy patients as control groups. Microvessel density (MVD) in bone marrow of36AL patients was determined by immunohistochemistry method with10benign hemopathy patients as control groups. And the EPCs correlation with clinical data and EPCs difference of peripheral blood and bone marrow were performed.[Results]1. The relative counting of EPCs in PB (0.113±0.137%) of AL patients at the time of diagnosis were significantly higher than control group (0.057±0.013%)(P＜0.01). The absolute counting of EPCs in PB (13.69±8.26/μl)of AL patients at the time of diagnosis were significantly higher than control group (1.86±0.18/μl)(P＜0.01).The relative counting of EPCs in BM (0.748±1.617%) of AL patients at the time of diagnosis were significantly higher than control group (0.087±0.027%)(P＜0.01). The absolute counting of EPCs in BM (119.46±72.23/μl) of AL patients at the time of diagnosis were significantly higher than control group (23.21±12.59/μl)(P＜0.01).2.The relative counting of EPCs in PB(0.069±0.023%)of CR group were significantly lower than before treatment (0.201±0.183%)(P＜0.05), however that of NR group had no significant difference than before treatment (P＞0.05).The absolute counting of EPCs in PB (2.54±2.12/μl) of CR group were significantly lower than before treatment (14.45±10.76/μl)(P＜0.05), however that of NR group had no significant difference than before treatment (P＞0.05).The relative counting of EPCs in BM(0.098±0.039%) of CR group were significantly lower than control group (0.725±1.465%)(P＜0.05),however that of NR group had no significant difference than before treatment (P＞0.05).The absolute counting of EPCs in BM(26.32±17.44/μl) of CR group were significantly lower than control group (113.18±69.22/μl)(P＜0.05),however that of NR group had no significant difference than before treatment (P>0.05).3.The absolute counting of EPCs were significantly higher in BM (119.46±72.23/μl) than in PB (13.69±8.26/μl) of AL patients (P＜0.001).While the relative counting of EPCs had no significant difference between in BM (0.748±1.617%) and in PB (0.113±0.137%) of AL patients (P＞0.05).4. The level of EPCs whether in PB or in BM had no significant difference between AML and ALL (P＞0.05).5. EPCs absolute count in PB of AL has a positive correlation with β2-MG (r1=0.712, p=0.046) and LDH (r2=0.835, p=0.025).6. Compared with the control group(7.70±1.64/Hp), MVD in borrow marrow of acute leukemia patient (19.31±2.29/Hp)was significantly higher(P＜0.01).7. Absolute count of EPCs in bone marrow of AL patients was positively correlated with MVD value (r=0.963, P＜0.01) by Pearson correlation analysis.[Conclusion] EPCs counts in BM and PB of AL patients were significently higher than control group and the change may be related to progression, curative effect and prognosis of AL. The angiogenesis in AL were presented by that the quantity change of EPCs and obvioustly increased MVD in bone marrow were positively correlated.EPCs might play an important role in the microvessel hyperplasia in AL, and could be a new target for the treatment of AL.