| Objective : Primary hepatic carcinoma is one of the common types of malignant tumors with high level of malignancy, metastasis and poor prognosis, in which hepatocellular carcinoma (HCC) accounts for above 90%. Exairesis is the fist selection , but the rate of the recidivation and metastasis post operation is still quite high. So, it has very important clinical value to study on the mechanism of metastasis of HCC. Hypoxia is a common characteristic of locally advanced solid tumors that has been associated with diminished therapeutic response, and more recently, with malignant progression, that is, an increasing probability of recurrence, loco regional spread, and distant metastasis. The hypoxia inducible factor 1(HIF-1) is a heterodimer transcription factor that is an important regulator of the growing tumor's response to hypoxia in mammal or human body. And it is a central regulatory factor of Hypoxia induced gene. The study indicated: HIF-1α, which has high expression in hepatocellular carcinoma and in other malignant tumors, is associated with the tumor aggressiveness, migration and mortality. In this study, we examined the expression of HIF-1αand VEGF through the application of YC-1(a inhibitor of HIF-1α) in vivo, furthermore, to approach the effects of YC-1 in mRNA and protein level in HCC.Methods: 1 The SMMC-7721 cell line was grown on a tissue culture plastic dish in RPMI 1640 containing 10% fetal bovine serum with essential amino acid, 100 units/ml penicillin, and 100μg/ml streptomycin and was maintained in a CO2 incubator at 37°C in a humidified atmosphere containing 5% CO2 and 95% humidity. A total of 16 male nude mice were inoculated subcutaneously with 1 million SMMC-7721 cells. Once the tumor grow to 100-150mm3, These mice were randomly divided into two groups. The first group (n = 8) was a control group to be treated with DMSO vehicle, and the second group (n = 8) was a experimental group to be treated with YC-1 (10 mg/kg,i.p. once a day) for 3 weeks.2 After the injections of YC-1 for 3 weeks, mice were executed and the length and short-diameter and weight of the transplantation tumor were measured. The expressions of HIF-1αand VEGF were detected by RT-PCR, Western-blot and immunohistochemsitry.Results: 1 In vivo, the efficacy of YC-1was determined in nude mice. After the experiment, Average tumor volum at 3 weeks for YC-1 treatment was 0.20±0.04 cm3 veresus 0.30±0.03 cm3 (33.3% inhibition, P<0.05) and average tumor weight at 3 weeks for YC-1 treatment was (0.39±0.18)g veresus (0.70±0.13)g (44.3% inhibition, P<0.05). there was a significant inhibition of SMMC-7721 cell tumor growth. 2 The expression of HIF-1αmRNA in experiment group (0.37±0.05)compared with control group(0.38±0.08)were not statistically significant (P > 0.05). The expression of VEGF mRNA in experiment group (VEGF1650.35±0.05,VEGF121 0.11±0.02)were obviously down-regulated compared with control group (VEGF1650.86±0.18,VEGF1210.29±0.06), the differences of the expression of VEGF mRNA were statistically significant (P<0.05).3 The expression of HIF-1αprotein in experiment group (0.89±0.24)were obviously down-regulated compared with control group(2.09±0.39), The expression of VEGF protein in experiment group (0.31±0.16)were also obviously down- regulated compared with control group(0.87±0.10), the differences of the expression of HIF-1αand VEGF protein were statistically significant (P<0.05).4 The expression of HIF-1αand VEGF was detected by immunohistochemsitry in two groups. The results indicated that the positive expression in experiment group was lower than control group.Conclutions: 1 The experiment revealed that YC-1 can suppress SMMC-7721 cell tumor growth in vivo.2 HIF-1αand VEGF expression was significantly down- regulated in the YC-1 treated tumors .3 The YC-1 suppress action for invasion and metastasis of tumor is achieved by down regulation of tumor HIF-1α. And its target gene VEGF was also been signifently down regulated. 4 There is the possibility to auxiliary therapy of hepatoculllar carcinoma by HIF-1α(as a target gene) inhibitor (YC-1).
|
PDF Full Text Request