BACKGROUND: The mechanism of regulation of KAI1, a specific tumor metastasis suppression gene, is controversial. A recent study showed that the synergism of wild-type p53 and JunB has the function of regulating the ex...BACKGROUND: The mechanism of regulation of KAI1, a specific tumor metastasis suppression gene, is controversial. A recent study showed that the synergism of wild-type p53 and JunB has the function of regulating the expression of KAI1, a metastasis inhibiting factor in prostate cancer cells. The wild-type p53 gene is an activator of apoptosis and is closely related to malignant tumor cell multiplication. JunB, a member of the fos/jun family, is a key component of activator protein transcription factor and a major target element in the transmission pathway of mitosis. This study aimed to evaluate the relationship between the expression of KAI1 and p53 combined with JunB in tumor tissues and clinical outcomes in hepatocellular carcinoma (HCC) patients. METHODS: Quantitative real-time RT-PCR, Western blotting techniques and immunohistochemistry were used to evaluate the expression of KAI1 mRNA, KAI1/CD82, p53 and JunB in HCC patients, and the relationship between their expression and the clinicopathological prognostic parameters was analyzed. RESULTS: In cancer tissues, the values for positive expression of KAI1 mRNA, KAI1/CD82, p53 and JunB were 31.25%, 26.25%, 48.75%, and 20.00%, respectively, while in adjacent non-tumor tissues, they were 100%, 94.74%, 2.63%, and 76.32%, respectively. There was no correlation between the expression levels of p53 or JunB and KAI1 mRNA or KAI1/CD82. However, there were significant correlations between the expression levels of p53 combined with JunB and not only KAI1 mRNA but also KAI1/CD82 proteins. CONCLUSIONS: When p53 dysfunction and low expression of JunB are simultaneous, they may play an important role in down-regulating the expression of KAI1 by synergism in HCC. But further studies in vivo and in vitro are needed to verify these results.展开更多
This study explored the double lethal effects of pEGFP-C1-wtp53/junB fusion gene on hepatocellular carcinoma (HCC) cells.wtp53/junB fusion gene was constructed and transformed into HepG2 cell line.Expression of KAI1 w...This study explored the double lethal effects of pEGFP-C1-wtp53/junB fusion gene on hepatocellular carcinoma (HCC) cells.wtp53/junB fusion gene was constructed and transformed into HepG2 cell line.Expression of KAI1 was detected by quantitative real-time PCR and Western blotting,cells apoptosis rate was detected by flow cytometry,proliferation of cells was detected by MTT chromometry,cell transmigration was detected by using transwell systems.The results showed that after transformation with pEGFP-C1-wtp53/JunB,the expression level of KAI1 protein was up-regulated,being 8.13 times the blank control group in HepG2 cells and significantly higher than 2.87 times which transformed with pEGFP-C1-JunB,3.11 times which transformed with pEGFP-C1-wtp53 (P<0.001).Apoptosis rate of HepG2 cells transformed with pEGFP-C1-wtp53/JunB was significantly higher than that of other groups (P<0.001),and invasive ability of HepG2 cells transformed with pEGFP-C1-wtp53/JunB was significantly lower than other groups (P<0.001).It was concluded that the fusion gene of wtp53 and JunB could not only inhibit the growth of hepatoma cells and promote tumor cell apoptosis,but also suppress the invasive ability of tumor cells by up-regulating the expression of KAI1.展开更多
Objective To analyze the upstream region of radiation-induced junB gene. Methods Four plasmids containing 250 bp, 590 bp, 900 bp and 1650 bp, and CAT reporter gene were constructed separately and introduced to L8704 c...Objective To analyze the upstream region of radiation-induced junB gene. Methods Four plasmids containing 250 bp, 590 bp, 900 bp and 1650 bp, and CAT reporter gene were constructed separately and introduced to L8704 cells. The cells were irradiated with 2 Gy X-rays and incubated at different intervals. Total RNA was extracted from the cells and fluctuation of the CAT mRNA level was assessed by the RNA ratio of CAT/β-actin measured by quantitative Northern blot hybridization. Results CAT mRNA expression containing 900 bp and 1560 bpjunB promoter remarkably and rapidly increased, and reached its peak 30min after 2 Gy X-my irradiation. Conclusions 590-900 bp fragments located in the upstream region of junB gene play an important role in the early process of cells against radiation.展开更多
Objective To explore JunB gene expression in spleen cells of mice after the whole body irradiation as well as in normal hematopoietic and leukemia cells in the primary culture after different dosages of X-ray irradia...Objective To explore JunB gene expression in spleen cells of mice after the whole body irradiation as well as in normal hematopoietic and leukemia cells in the primary culture after different dosages of X-ray irradiation. Methods Spleen cells were isolated from the mice irradiated with 3 Gy X-rays. Primary cultured cells from mice were incubated in different intervals after X-irradiation at different dosages. Total RNA was extracted from the cells and the fluctuation of JunB mRNA level was assessed by the RNA ratio of JunB/b-actin measured by quantitative Northern blot hybridization. Results After the mice were exposed to 3 Gy X-rays irradiation, JunB expression in spleen cells was remarkably and rapidly increased, and reached its peak 0.5 h later in C3H/He mice and 1 h later in Balb/c mice. In the primary culture of normal spleen and leukemia cells, JunB mRNA levels increased 30 min after irradiation. The enhanced levels of JunB mRNA were returned to a normal level within 240 min after irradiation. Conclusions JunB gene is responsive to ionizing irradiation and is induced at immediate-early phase after the stimulation. This suggests that the JunB gene plays an important role in the early process of the cells against radiation.展开更多
基金supported by a grant from the Shaanxi Science and Technology Research Project,China(2007K09-05)
文摘BACKGROUND: The mechanism of regulation of KAI1, a specific tumor metastasis suppression gene, is controversial. A recent study showed that the synergism of wild-type p53 and JunB has the function of regulating the expression of KAI1, a metastasis inhibiting factor in prostate cancer cells. The wild-type p53 gene is an activator of apoptosis and is closely related to malignant tumor cell multiplication. JunB, a member of the fos/jun family, is a key component of activator protein transcription factor and a major target element in the transmission pathway of mitosis. This study aimed to evaluate the relationship between the expression of KAI1 and p53 combined with JunB in tumor tissues and clinical outcomes in hepatocellular carcinoma (HCC) patients. METHODS: Quantitative real-time RT-PCR, Western blotting techniques and immunohistochemistry were used to evaluate the expression of KAI1 mRNA, KAI1/CD82, p53 and JunB in HCC patients, and the relationship between their expression and the clinicopathological prognostic parameters was analyzed. RESULTS: In cancer tissues, the values for positive expression of KAI1 mRNA, KAI1/CD82, p53 and JunB were 31.25%, 26.25%, 48.75%, and 20.00%, respectively, while in adjacent non-tumor tissues, they were 100%, 94.74%, 2.63%, and 76.32%, respectively. There was no correlation between the expression levels of p53 or JunB and KAI1 mRNA or KAI1/CD82. However, there were significant correlations between the expression levels of p53 combined with JunB and not only KAI1 mRNA but also KAI1/CD82 proteins. CONCLUSIONS: When p53 dysfunction and low expression of JunB are simultaneous, they may play an important role in down-regulating the expression of KAI1 by synergism in HCC. But further studies in vivo and in vitro are needed to verify these results.
基金supported by a grant from the Fundamental Research Funds for the Central Universities,China (No.XJJ2010010)
文摘This study explored the double lethal effects of pEGFP-C1-wtp53/junB fusion gene on hepatocellular carcinoma (HCC) cells.wtp53/junB fusion gene was constructed and transformed into HepG2 cell line.Expression of KAI1 was detected by quantitative real-time PCR and Western blotting,cells apoptosis rate was detected by flow cytometry,proliferation of cells was detected by MTT chromometry,cell transmigration was detected by using transwell systems.The results showed that after transformation with pEGFP-C1-wtp53/JunB,the expression level of KAI1 protein was up-regulated,being 8.13 times the blank control group in HepG2 cells and significantly higher than 2.87 times which transformed with pEGFP-C1-JunB,3.11 times which transformed with pEGFP-C1-wtp53 (P<0.001).Apoptosis rate of HepG2 cells transformed with pEGFP-C1-wtp53/JunB was significantly higher than that of other groups (P<0.001),and invasive ability of HepG2 cells transformed with pEGFP-C1-wtp53/JunB was significantly lower than other groups (P<0.001).It was concluded that the fusion gene of wtp53 and JunB could not only inhibit the growth of hepatoma cells and promote tumor cell apoptosis,but also suppress the invasive ability of tumor cells by up-regulating the expression of KAI1.
基金This project was supported by Japanese Research Development Corporation (JRDC).
文摘Objective To analyze the upstream region of radiation-induced junB gene. Methods Four plasmids containing 250 bp, 590 bp, 900 bp and 1650 bp, and CAT reporter gene were constructed separately and introduced to L8704 cells. The cells were irradiated with 2 Gy X-rays and incubated at different intervals. Total RNA was extracted from the cells and fluctuation of the CAT mRNA level was assessed by the RNA ratio of CAT/β-actin measured by quantitative Northern blot hybridization. Results CAT mRNA expression containing 900 bp and 1560 bpjunB promoter remarkably and rapidly increased, and reached its peak 30min after 2 Gy X-my irradiation. Conclusions 590-900 bp fragments located in the upstream region of junB gene play an important role in the early process of cells against radiation.
文摘Objective To explore JunB gene expression in spleen cells of mice after the whole body irradiation as well as in normal hematopoietic and leukemia cells in the primary culture after different dosages of X-ray irradiation. Methods Spleen cells were isolated from the mice irradiated with 3 Gy X-rays. Primary cultured cells from mice were incubated in different intervals after X-irradiation at different dosages. Total RNA was extracted from the cells and the fluctuation of JunB mRNA level was assessed by the RNA ratio of JunB/b-actin measured by quantitative Northern blot hybridization. Results After the mice were exposed to 3 Gy X-rays irradiation, JunB expression in spleen cells was remarkably and rapidly increased, and reached its peak 0.5 h later in C3H/He mice and 1 h later in Balb/c mice. In the primary culture of normal spleen and leukemia cells, JunB mRNA levels increased 30 min after irradiation. The enhanced levels of JunB mRNA were returned to a normal level within 240 min after irradiation. Conclusions JunB gene is responsive to ionizing irradiation and is induced at immediate-early phase after the stimulation. This suggests that the JunB gene plays an important role in the early process of the cells against radiation.