摘要
To examine the effect of transcatheter arterial embolization （TAE） of liver tumors on hypoxia-inducible factor-1α （HIF-1α） expression in the residual viable tumor, a total of 30 New Zealand White rabbits implanted with VX2 liver tumor were divided into 2 groups. TAE-treated group animals （n=15） were subjected to TAE with 150–250 μm polyvinyl alcohol particles. Control group animals （n=15） underwent sham embolization with distilled water. Six hours, 3 days or 7 days after TAE, the animals were sacrificed, and samples of tumor and adjacent normal liver tissue were harvested. Expression of HIF-1α protein was examined immunohistochemically. Real-time PCR was performed to examine the HIF-1α mRNA levels. Our results showed that HIF-1α protein was expressed in the VX2 tumors but not in the adjacent normal liver tissue. The HIF-1α-positive tumor cells were located predominantly at the periphery of necrotic tumor regions. The mean levels of HIF-1α protein were significantly higher in TAE-treated tumors than those in control tumors （P=0.002）. Among the three sacrificing time points, the difference in increase in HIF-1α protein was significant between the two groups at the sacrificing time point of 6 h and 3 days after TAE （P=0.020, P=0.031, respectively）, whereas no significant increase was noted 7 days after TAE （P=0.502）. In contrast, although HIF-1α mRNA was expressed in TAE-treated and control VX2 tumors, there existed no significant difference in the HIF-1α mRNA level between the two groups （P=0.372）. It is concluded that TAE of liver tumors increases the expression of HIF-1α at protein level in the residual viable tumor, which could be attributed to hypoxia generated by the procedure.
To examine the effect of transcatheter arterial embolization （TAE） of liver tumors on hypoxia-inducible factor-1α （HIF-1α） expression in the residual viable tumor, a total of 30 New Zealand White rabbits implanted with VX2 liver tumor were divided into 2 groups. TAE-treated group animals （n=15） were subjected to TAE with 150–250 μm polyvinyl alcohol particles. Control group animals （n=15） underwent sham embolization with distilled water. Six hours, 3 days or 7 days after TAE, the animals were sacrificed, and samples of tumor and adjacent normal liver tissue were harvested. Expression of HIF-1α protein was examined immunohistochemically. Real-time PCR was performed to examine the HIF-1α mRNA levels. Our results showed that HIF-1α protein was expressed in the VX2 tumors but not in the adjacent normal liver tissue. The HIF-1α-positive tumor cells were located predominantly at the periphery of necrotic tumor regions. The mean levels of HIF-1α protein were significantly higher in TAE-treated tumors than those in control tumors （P=0.002）. Among the three sacrificing time points, the difference in increase in HIF-1α protein was significant between the two groups at the sacrificing time point of 6 h and 3 days after TAE （P=0.020, P=0.031, respectively）, whereas no significant increase was noted 7 days after TAE （P=0.502）. In contrast, although HIF-1α mRNA was expressed in TAE-treated and control VX2 tumors, there existed no significant difference in the HIF-1α mRNA level between the two groups （P=0.372）. It is concluded that TAE of liver tumors increases the expression of HIF-1α at protein level in the residual viable tumor, which could be attributed to hypoxia generated by the procedure.
基金
supported by grants from National Natural Sciences Foundation of China (No 30970804)
863 Na-tional High Technology Research and Development Program of China (No 2006AA03Z332)
