The Effect Of Curcumin On The Expression Of HIF-1α And Vegf In Pancreatic Carcinoma PANC-1in Vitro Hypoxia

Objective:To study the inhibitory effect of curcumin on induction of HIF-la and VEGF gene in human pancreatic carcinoma PANC-1cells under in vitro hypoxia, we use lots of test methods. At last we investigate the mechanism of expression of HIF-la and VEGF gene under the action of curcumin.Methods:1. PANC-1cells in vitro were cultivated under the hypoxic microenvironment, which was intervened by different dosages of curcumin (Oμmol/L,0.1μmol/L,10μmol/L,100μmol/L.) for24hours. Merisis of PANC-1cells were detected by inverted phase contract microscope.2. The survival rate of PANC-1was measured by MTT method, when the different dosages of Curcumin (Oμmol/L,0.1μmol/L,10μmol/L,100μmol/L.) was added in culture flask and PANC-1cells was intervened for24hours in vitro hypoxia. Diagram of curves indicated intervention result directly.3. RT-PCR measure HIF-la and VEGF mRNA expression of PANC-1cells, which was intervened by above concentrations.4. Through the above process. The expression of HIF-la was detected by ELISA.Results:1. The detection result was indicated that the inhibitory effect of curcumin on the proliferation of human pancreatic carcinoma PANC-1cells had no obvious difference among different doses of curcumin. Compared with control group, the inhibitory rate of cells is between90%and95%in hypoxic microenvironment after24hours.2. The result of PANC-1cells intervened by curcumin demonstrated the drug could induced apoptosis of PANC-1cells, but within a certain range concentration and intervention time of the drug, the effect of the inhibition rate had no significant changes and was about95%.when the intervention time increased(48h,72h,96h), the inhibitory rates was gadually obvious.3. As shown by the RT-PCR, HIF-la expression of drug groups was not obvious in comparison with control group. But the expression of VEGF mRNA had changed evidently with the increase of concentration and had a clearly dose dependence, the expression of VEGF dramatically decreased, when the dose of curcumin gradually increased.4. The result of ELISA showed that HIF-la protein levels of drug group obviously decreased in comparison with control group (F=138.43, P<0.01) and were dose-dependently suppressed with the increasing doses of curcumin. Conclusions:1. Curcumin could inhibit the proliferation of PANC-1cells. but with the increase of dose, no significant difference had happened in a certain range of less than100μmol/L and in24hours. When the intervention time and drug dosage increased, the inhibitory rate was gradually obvious.2. Inhibitory effect of curcumin on the expression of HIF-la protein in human pancreatic cancer PANC-1cells was through post-transcriptional mechanisms, not through cell apoptosis or cell proliferation pathway.3. In order to inhibit neovascularization mechanism of human pancreatic carcinoma PANC-1cells, Curcumin depend on the blockade of HIF-la protein synthesis to cut target gene VEGF expression of its downstream achieved.