The Correlation Of Phd2 Expression With Angiogenesis In Hepatocellular Carcinoma

Objective:To explore the role of PHD2 in hepatocellular carcinoma angiogenesis.Methods:(1) Immunohistochemistry S-P method was applicated to examine the PHD2 expression in 72 HCC tissues,72 paracarcinomatous liver tissues and 13 normal liver tissue, and CD34 monoclonal antibody was used to detect microvessel density (MVD) in 72 HCC tissues. The correlation of PHD2 with clinicopathological indices and microvessel density data were analysed. (2) HMEC-1 cell line was cultured in vitro, then, the cell lines were treated with difference concentration (0μmol/L, 50μmol/L,100μmol/L,150μmol/L) of CoCl2 as treatment group, cell line treatment with PBS as control group. Then, the expression of level PHD2 protein was detected by Western blot. Microvessel formation capability of HMEC-1 cell in matrigel was examined by two-dimensional vascular formation test.Results:(1) The expression of PHD2 in HCC tissues(22.2%,16/72) was significantly lower than the paracarcinomatous liver tissues(68.1 %,49/72) and normal liver tissue(84.6%,11/13),(all P<0.05). (2) In 72 HCC tissues,the MVD in PHD2 positive expression group was lower than that in PHD2 negative expression group (52.1±4.3 vs 69.2±5.5, P<0.05). PHD2 expression and MVD had negative correlation (r=-0.437, P= 0.016). (3) After HMEC-1 cells incubating in Oh,6h,12h,24h with 150μmol/L concentration of CoCl2, the expression of PHD2 protein was gradually reduced, the optical density was 0.92±0.11,0.89±0.12,0.43±0.09,0.25±0.02 respectively, P<0.05); the expression of HIF-1αprotein was gradually increased, the optical density was 0.37±0.14,0.41±0.12,0.63±0.15,0.93±0.01, respectively P<0.05); and the expression of VEGF protein was gradually increased, the optical density was 0.29±0.07,0.39±0.06,0.52±0.03,0.86±0.01, respectively P<0.05). (4) Compared with the control group, tube formation capability of HMEC-1 cell in matrigel was significantly decreased after treated by CoCl2, (12±2 vs 25±4, P<0.05).Conclusion:(1) The expression of PHD2 protein in HCC tissues may be relevant to angiogenesis. (2) In hypoxic microenvironment, the expression of PHD2 were decreased, leading to endothelial cell proliferation increased, however, the tube formation capability of the cell in matrigel decreased, HCC tumor vascular maturity decreased, which is the important factors to promote invasion and metastasis of HCC.