Experimental Studies Of RhIFN-α And RhIL-2 On Antiangiogenesis

Objective The cellular and molecularly regulatory mechanism of rhIFN-α and rhIL-2 on vascular endothelial cell were investigated in this study. Meanwhile, the possibility of synergistic between them was also discussed. This study provided the experimental evidence on cytokines treating malignant tumor and hematologic malignancies for clinical propose. Methods The HUVECs (human umbilical vein endothelial cells) were selected to be the models and the following aspects were studied: 1. Effects of rhIFN-αor rhIL-2 on proliferation in HUVECs. (1) The human umbilical vein endothelial cells were isolated, cultured and identified. (2) The effective limitation and concentration of rhIFN-α or rhIL-2 on HUVECs were determined by way of MTT. 2. Effects of rhIFN-αor rhIL-2 on cell cycle of HUVECs. The S phase of cell cycle of rhIFN-αor rhIL-2 induced HUVECs was analysised by way of flow-cytometer. 3. Effects of rhIFN-αor rhIL-2 on migrating rate of HUVECs. Effects of rhIFN-α or rhIL-2 on migration inhibiting rate of HUVECs were studied by way of agarose scraping. 4. Effects of rhIFN-αor rhIL-2 on secreting VEGF of HUVECs. Effects of rhIFN-αor rhIL-2 on secreting VEGF of HUVECs were studied by way of enzyme-linked immunosorbent assay (ELISA). 5. Effects of rhIFN-αor rhIL-2 on VEGF mRNA expression of HUVECs Effects of rhIFN-α or rhIL-2 on VEGF mRNA expression of HUVECs were investigated using reverse transcriptase-polymerase chain reaction (RT-PCR) technique. Results The cytokines rhIFN-αor rhIL-2 could inhibit proliferation, migration and decrease DNA synthesis in HUVECs (P<0.01). They showed some synergistic effects when they were combined (P<0.01). VEGF content in supernatant of HUVECs culture in rhIFN-α or rhIL-2 group was higher than those in the control group, but VEGF content in combination group was lower than those in the control group. The difference was insignificant (P>0.05).Both combination group and rhIL-2 group could inhibit the VEGF mRNA expression of HUVECs (P<0.01). The difference between control group and rhIFN-αgroup was insignificant (P>0.05). The inhibited VEGF mRNA expression in rhIL-2 is stronger than that of combination group (P<0.01). There was no synergistic effect. Conclusion The cytokines rhIFN-αor rhIL-2 could inhibit the proliferation and migration in HUVECs, and decrease the DNA synthesis of it as well. There were some synergistic effects when theywere combined. The difference between rhIFN-αand rhIL-2 in inducing HUVECs secreting VEGF was insignificance. They could inhibit the VEGF mRNA expression of HUVECs. The results suggest that these cytokines might have a certain inhibiting effect in the angiogenesis. The above results can provide some evidence for the adoption of rhIFN-α or rhIL-2 in clinic on hematologic malignancies, such as leukemia and so on.