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, Golgiosom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, Golgiosom