BACKGROUND: Gallbladder carcinoma is a lethal malignant neoplasm with dismal surgical results. Unfortunately, the adjuvant therapies for gallbladder carcinoma such as chemotherapy and radiotherapy are also disappointi...BACKGROUND: Gallbladder carcinoma is a lethal malignant neoplasm with dismal surgical results. Unfortunately, the adjuvant therapies for gallbladder carcinoma such as chemotherapy and radiotherapy are also disappointing. We reported that norcantharidin (NCTD), a demethylated form of cantharidin, which is an active ingredient of the Chinese medicine Mylabris, was used against human gallbladder carcinoma GBC-SD cells. In the present study, we further studied the mechanism underlying the inhibitory effect of NCTD on growth of human gallbladder carcinoma GBC-SD cells in vitro. METHODS: Human gallbladder carcinoma GBC-SD cells were grown in cell culture and divided into a NCTD group and a control group. The inhibitory effect of NCTD on growth of GBC-SD cells was investigated by evaluation of proliferation, cell cycle, apoptosis and morphological changes of the cells. Cell proliferation was assessed by tetrazolium-based colorimetric assay. The induction of cell cycle arrest and apoptosis was measured by flow cytometry. The morphological changes of the cells were observed by light- and electron-microscopy. To elucidate the anticancer mechanism of NCTD, expression of the proliferation-related gene proteins PCNA, Ki-67, cyclin-D-1 and p27 and the apoptosis-related gene proteins Bcl-2, Bax and Survivin were determined by the streptavidin-biotin complex method and RT-PCR. RESULTS: NCTD inhibited the proliferation of GBCSD cells in a dose- and time-dependent manner, with an IC50 of 56.18 mu g/ml at 48 hours. The flow cytometric profiles revealed that NCTD (at the IC50 for 48 hours) significantly increased the proportion of cells in G(2)/M phase and significantly decreased the proportion of cells in S phase, with a significantly increased rate of cell apoptosis. After treatment with the 48-hour IC50 dose of NCTD, cell shrinkage, vacuolar cytoplasm, membrane budding, karyorrhexis, karyolysis, chromosome condensation and chromatin aggregation in some GBCSD cells were observed by light-microscopy; decreased microvilli, Golgiosome atrophy, mitochondrial swelling, nuclear shrinkage, chromosome condensation and typical apoptosis bodies were seen by electron-microscopy, and the morphological changes of apoptosis occurred in GBCSD cells. The expression of PCNA, Ki-67 and Bcl-2 proteins decreased significantly; the Pix or relative levels of PCNA mRNA, cyclin-D-1 mRNA, Bcl-2 mRNA and Survivin mRNA decreased significantly, whereas the Pix or relative levels of p27 mRNA and Bax mRNA increased significantly. CONCLUSIONS: NCTD inhibits the growth of human gallbladder carcinoma GBC-SD cells in vitro. Its anticancer mechanism may correlate with inhibition of cell proliferation, arrest of the cell cycle, blockage of DNA synthesis, influence on cell metabolism, induction of cell apoptosis and influence on expression of the proliferation-related genes PCNA, Ki-67, cyclin-D-1 and p27, and the apoptosis-related genes Bcl-2, Bax and Survivin in human gallbladder carcinoma GBC-SD cells.展开更多
BACKGROUND: Gallbladder carcinoma, a lethal malignant neoplasm with poor prognosis, has dismal results of surgical resection and chemoradiotherapy. We previously reported that norcantharidin (NCTD) is useful against g...BACKGROUND: Gallbladder carcinoma, a lethal malignant neoplasm with poor prognosis, has dismal results of surgical resection and chemoradiotherapy. We previously reported that norcantharidin (NCTD) is useful against growth, proliferation, and invasion of human gallbladder carcinoma GBC-SD cells in vitro. In this study, we further studied the inhibitory effect of NCTD on the growth of xenografted tumors of human gallbladder carcinoma in nude mice in vivo and the underlying mechanisms. METHODS: The tumor xenograft model of human gallbladder carcinoma in nude mice in vivo was established with subcutaneous GBC-SD cells. The experimental mice were randomly divided into control, 5-FU, NCTD, and NCTD+5-FU groups which were given different treatments. Tumor growth in terms of size, growth curve, and inhibitory rate was evaluated. Cell cycle, apoptosis, and morphological changes of the xenografted tumors were assessed by flow cytometry and light/electron microscopy. The expression of the cell cycle-related proteins cyclin-D1 and p27 as well as the apoptosis-related proteins Bcl-2, Box, and survivin were determined by the streptavidin-biotin complex (SABC) method and RT-PCR. RESULTS: NCTD inhibited the growth of the xenografted tumors in a dose- and time-dependent manner. Tumor volume decreased (5.61+/-0.39 vs. 9.78+/-0.61 cm(3), P=0.000) with an increased tumor inhibitory rate (42.63% vs. 0%, P=0.012) in the NTCD group compared with the control group. The apoptosis rate increased (15.08+/-1.49% vs. 5.49+/-0.59%, P=0.0001) along with a decreased percentage of cells in S phase (43.47+/-2.83% vs. 69.85+/-1.96%, P=0.0001) in the NTCD group compared with the control group. The morphological changes of apoptosis such as nuclear shrinkage, chromatin aggregation, chromosome condensation, and typical apoptosis bodies in the xenografted tumor cells induced by NCTD were observed by light and electron microscopy. The expression of cyclin-D1, Bcl-2 and survivin proteins/mRNAs decreased significantly, with increased expression of p27 and Bax proteins/mRNAs in the NCTD group compared with the control group. CONCLUSION: NCTD inhibits the growth of xenografted tumors of human gallbladder carcinoma in nude mice by inducing apoptosis and blocking the cell cycle in vivo.展开更多
文摘BACKGROUND: Gallbladder carcinoma is a lethal malignant neoplasm with dismal surgical results. Unfortunately, the adjuvant therapies for gallbladder carcinoma such as chemotherapy and radiotherapy are also disappointing. We reported that norcantharidin (NCTD), a demethylated form of cantharidin, which is an active ingredient of the Chinese medicine Mylabris, was used against human gallbladder carcinoma GBC-SD cells. In the present study, we further studied the mechanism underlying the inhibitory effect of NCTD on growth of human gallbladder carcinoma GBC-SD cells in vitro. METHODS: Human gallbladder carcinoma GBC-SD cells were grown in cell culture and divided into a NCTD group and a control group. The inhibitory effect of NCTD on growth of GBC-SD cells was investigated by evaluation of proliferation, cell cycle, apoptosis and morphological changes of the cells. Cell proliferation was assessed by tetrazolium-based colorimetric assay. The induction of cell cycle arrest and apoptosis was measured by flow cytometry. The morphological changes of the cells were observed by light- and electron-microscopy. To elucidate the anticancer mechanism of NCTD, expression of the proliferation-related gene proteins PCNA, Ki-67, cyclin-D-1 and p27 and the apoptosis-related gene proteins Bcl-2, Bax and Survivin were determined by the streptavidin-biotin complex method and RT-PCR. RESULTS: NCTD inhibited the proliferation of GBCSD cells in a dose- and time-dependent manner, with an IC50 of 56.18 mu g/ml at 48 hours. The flow cytometric profiles revealed that NCTD (at the IC50 for 48 hours) significantly increased the proportion of cells in G(2)/M phase and significantly decreased the proportion of cells in S phase, with a significantly increased rate of cell apoptosis. After treatment with the 48-hour IC50 dose of NCTD, cell shrinkage, vacuolar cytoplasm, membrane budding, karyorrhexis, karyolysis, chromosome condensation and chromatin aggregation in some GBCSD cells were observed by light-microscopy; decreased microvilli, Golgiosome atrophy, mitochondrial swelling, nuclear shrinkage, chromosome condensation and typical apoptosis bodies were seen by electron-microscopy, and the morphological changes of apoptosis occurred in GBCSD cells. The expression of PCNA, Ki-67 and Bcl-2 proteins decreased significantly; the Pix or relative levels of PCNA mRNA, cyclin-D-1 mRNA, Bcl-2 mRNA and Survivin mRNA decreased significantly, whereas the Pix or relative levels of p27 mRNA and Bax mRNA increased significantly. CONCLUSIONS: NCTD inhibits the growth of human gallbladder carcinoma GBC-SD cells in vitro. Its anticancer mechanism may correlate with inhibition of cell proliferation, arrest of the cell cycle, blockage of DNA synthesis, influence on cell metabolism, induction of cell apoptosis and influence on expression of the proliferation-related genes PCNA, Ki-67, cyclin-D-1 and p27, and the apoptosis-related genes Bcl-2, Bax and Survivin in human gallbladder carcinoma GBC-SD cells.
文摘BACKGROUND: Gallbladder carcinoma, a lethal malignant neoplasm with poor prognosis, has dismal results of surgical resection and chemoradiotherapy. We previously reported that norcantharidin (NCTD) is useful against growth, proliferation, and invasion of human gallbladder carcinoma GBC-SD cells in vitro. In this study, we further studied the inhibitory effect of NCTD on the growth of xenografted tumors of human gallbladder carcinoma in nude mice in vivo and the underlying mechanisms. METHODS: The tumor xenograft model of human gallbladder carcinoma in nude mice in vivo was established with subcutaneous GBC-SD cells. The experimental mice were randomly divided into control, 5-FU, NCTD, and NCTD+5-FU groups which were given different treatments. Tumor growth in terms of size, growth curve, and inhibitory rate was evaluated. Cell cycle, apoptosis, and morphological changes of the xenografted tumors were assessed by flow cytometry and light/electron microscopy. The expression of the cell cycle-related proteins cyclin-D1 and p27 as well as the apoptosis-related proteins Bcl-2, Box, and survivin were determined by the streptavidin-biotin complex (SABC) method and RT-PCR. RESULTS: NCTD inhibited the growth of the xenografted tumors in a dose- and time-dependent manner. Tumor volume decreased (5.61+/-0.39 vs. 9.78+/-0.61 cm(3), P=0.000) with an increased tumor inhibitory rate (42.63% vs. 0%, P=0.012) in the NTCD group compared with the control group. The apoptosis rate increased (15.08+/-1.49% vs. 5.49+/-0.59%, P=0.0001) along with a decreased percentage of cells in S phase (43.47+/-2.83% vs. 69.85+/-1.96%, P=0.0001) in the NTCD group compared with the control group. The morphological changes of apoptosis such as nuclear shrinkage, chromatin aggregation, chromosome condensation, and typical apoptosis bodies in the xenografted tumor cells induced by NCTD were observed by light and electron microscopy. The expression of cyclin-D1, Bcl-2 and survivin proteins/mRNAs decreased significantly, with increased expression of p27 and Bax proteins/mRNAs in the NCTD group compared with the control group. CONCLUSION: NCTD inhibits the growth of xenografted tumors of human gallbladder carcinoma in nude mice by inducing apoptosis and blocking the cell cycle in vivo.
