Expression and significance of CCR7 and VEGF in retinal endothelial cell under hypoxia

Abstract:

AIM:To explore the expression and significance of CC chemokine receptor7(CCR7)and vascular endothelial growth factor(VEGF)in retinal endothelial cell(REC)under hypoxia.

METHODS:Rhesus choroid-retinal vascular endothelial cells(RF/6A)were cultured under normoxic and hypoxic conditions in vitro and divided into the normoxia group, the hypoxia control group(transiently transfected with the vector plasmid)and the treated group(transiently transfected with the CCR7siRNA recombinant plasmid). Plasmids were transiently transfected in RF/6A cells using Lipofectamine^TM2000(LF2000). RF/6A cells proliferation and apoptosis detected by CCK8 and flow cytometry and the protein and mRNA expression of CCR7 and VEGF were measured by Western blot and RT-PCR.

RESULTS:The cell growth rate became slower and apoptosis rate became increased in the hypoxia group than that in the normoxia group, and in the treated group than that in the normoxia and hypoxia control groups(all P<0.05). Compared with the normoxia group, there were high protein and mRNA expression of CCR7 and VEGF in the hypoxia control group, the differences had statistical significance(t_CCR7protein=3.38, t_VEGFprotein=4.75, t_CCR7mRNA=4.27, t_VEGFmRNA=5.34, all P<0.05). And there was an obvious positive correlation between the expression of CCR7 and VEGF(r_protein=0.71, r_mRNA=0.83, all P<0.05). The protein and mRNA expression of CCR7 and VEGF were obviously decreased in the treated group compared with the normoxia and hypoxia control groups(all P<0.05).

CONCLUSION: CCR7 can upregulate the expression of VEGF in REC under hypoxia. CCR7- VEGF signaling pathway may have potential function in the retinal neovascularization(RNV), and CCR7siRNA may provide an effective method for RNV.