[Expression and clinical significance of vascular endothelial growth factor and its receptors in multiple myeloma]

Bone marrow angiogenesis plays an important role in the development and prognosis of multiple myeloma (MM). Vascular endothelial growth factor (VEGF) is the most potent stimulatory factor in angiogenesis. This study was to examine the expression of VEGF and its receptors in MM, and analyze their correlations to the tumorigenesis and development of MM.

Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect mRNA expression of VEGF, Flt-1, and KDR in bone marrow samples from 12 newly diagnosed MM patients, 23 relapsed/refractory MM patients, 16 control people, and in KM3 cells.

The positive rates of VEGF and Flt-1 were significantly higher in MM patients than in control people (62.9% vs. 18.8%, P<0.01; 80% vs. 31.3%, P<0.01). The mRNA levels of VEGF and Flt-1 were significantly higher in MM patients than in control people (0.41+/-0.19 vs. 0.06+/-0.01, P<0.05; 0.60+/-0.33 vs. 0.08+/-0.03, P<0.01). The positive rates of VEGF and Flt-1 mRNA were not significantly different between newly diagnosed and relapsed/refractory MM patients (66.7% vs. 60.9%, P>0.05; 83.3% vs. 78.3%, P>0.05), and between stage II MM and stage III MM (50% vs. 73.7%, P>0.05; 81.3% vs. 78.9%, P>0.05). The mRNA levels of VEGF and Flt-1 were significantly higher in relapsed/refractory MM patients than in newly diagnosed MM patients (0.49+/-0.20 vs. 0.28+/-0.04, P<0.05; 0.70+/-0.38 vs. 0.41+/-0.06, P<0.05), and were significantly higher in stage III MM than that in stage II MM (0.48+/-0.19 vs. 0.28+/-0.09, P<0.05; 0.75+/-0.35 vs. 0.41+/-0.21, P<0.05). KDR was detected only in 3 MM patients and was not detected in control group.

High expression of VEGF and Flt-1 mRNA is associated with the development of MM.