肝缺氧诱导因子-1α与肝癌发生、发展及治疗研究新进展

Relationship between blood flow assessed by ultrasound, MVD and expression of HIF-1α in hepatocellular carcinoma

AIM: To investigate the ultrasonic signs of hepatocellular carcinoma (HCC), the expression of hypoxia inducible factor-1 alpha (HIF-1α) and microvessel density (MVD), and to analyze their correlations.

METHODS: Sixty patients who underwent duplex sonography and color Doppler ultrasonography before surgery and were surgically proved to have HCC were included. Immunohistochemical method was used to detect the expression of HIF-1α and MVD in HCC.

RESULTS: There was a correlation between blood flow grade and MVD. In liver cancer tissues when blood flow classification was grade Ⅲ, the rates of HIF-1α and MVD expression were highest [81.6% (92.61% ± 3.10%), 80.1% (85.16% ± 2.33%)], significantly higher than those in normal liver tissues (12.28% ± 7.21%, 11.33%±7.21%, P < 0.05 for both). The expression of HIF-1α is related closely to hepatocellular carcinoma angiogenesis; higher expression of MVD was associated with higher expression of HIF-1α and more abundant blood flow.

CONCLUSION: Combination of color Doppler flow imaging and immunohistochemical parameters is useful for evaluating the angiogensis of HCC.

Extracellular HSP70 peptide complexes alter expression of Glut1 and VEGF in HepG 2 cells via HIF-1α

AIM: To investigate the effect of extracellular heat shock protein 70 (HSP70)-peptide complexes (HSP70-PCs) on the expression of glucose transporter 1 (Glut1) and vascular endothelial growth factor (VEGF) in HepG2 cells and to explore the possible mechanisms involved.

METHODS: HepG2 cells were randomly divided into three groups: a control group, an extracellular HSP70 PC (final concentration, 2 μg/mL) group and an extracellular HSP70/HSP70-PCs + HIF-1α siRNA group. The expression of HIF-1α, Glut1 and VEGF was examined by real-time RT-PCR and Western blot.

RESULTS: Compared with the control group, the expression of HIF-1α, Glut1 and VEGF was significantly increased in the extracellular HSP70-PC group (all P < 0.05), suggesting that extracellular HSP70 PCs promote the expression of HIF-1α, Glut1 and VEGF in HepG2 cells. SiRNA-mediated blockage of HIF-1α significantly inhibited the up-regulation of Glut1 and VEGF expression in HepG2 cells (both P < 0.05).

CONCLUSION: Extracellular HSP70-PCs promote the expression of Glut1 and VEGF via HIF-1α in HepG 2 cells.