Attrora-A kinase, a serine/threonine protein kinase, is a potential oncogene. Amplification and overexpression of Aurora-A have been found in several types of human tumors, including esophageal squamous cell carcinoma...Attrora-A kinase, a serine/threonine protein kinase, is a potential oncogene. Amplification and overexpression of Aurora-A have been found in several types of human tumors, including esophageal squamous cell carcinoma （ESCC）. It has been demonstrated that cells overexpressing Attrora-A are more resistant to cisplatin-induced apoptosis. However, the molecular mechanisms mediating these effects remain largely unknown. In this report, we showed that overexpression of Attrora-A through stable transfection of pEGFP-Aurora-A in human ESCC KYSE150 cells significantly promoted cell proliferation and inhibited cisplatin- or UV irradiation-induced apoptosis. Cleavages of caspase-3 and poly （ADPribose） polymerase （PARP） in Attrora-A overexpressing cells were substantially reduced after cisplatin or UV treatment. Furthermore, we found that silencing of endogenous Aurora-A kinase with siRNA substantially enhanced sensitivity to cisplatin- or UV-induced apoptosis in human ESCC EC9706 cells. In parallel, overexpression of Aurora-A potently upregulated the expression of Bcl-2. Moreover, the knockdown of Bcl-2 by siRNA abrogated the Aurora-A＇s effect on inhibiting apoptosis. Taken together, these data provide evidence that Aurora-A overexpression promoting cell proliferation and inhibiting apoptosis, suggesting a novel mechanism that is closely related to malignant phenotype and anti-cancer drugs resistance of ESCC cells.展开更多
Objective： To observe the effect of the artesunate （ART） on cellular proliferation in vitro, to search for the possible anti-tumor mechanism of ART on endometrial carcinoma at the molecular level and to provide the...Objective： To observe the effect of the artesunate （ART） on cellular proliferation in vitro, to search for the possible anti-tumor mechanism of ART on endometrial carcinoma at the molecular level and to provide the experimental and theoretical foundations for the clinical applications of ART. Methods： The cell proliferation was observed by microscope; MTT was used to examine the effects of ART on proliferation of HEC-1B cells, and flow cytometric analysis was used to detect cell cycle and apoptosis. The human endometrial carcinoma HEC-1B cells were conventionally cultured; ART was administered with a concentration of 40 μg/ml before the total RNA were extracted, mRNA expression of Survivin, Caspase-3, N-Cadherin, E-Cadherin, Fibronectinl and Cox-2 were detected using RT-PCR. Results： ART reduced proliferation in human endometrial carcinoma cell line HEC-1B in a dose- and time-dependent effect. The cells of G0/G1 stage were significantly increased （P〈0.05）, but the cells of G2/M stages were significantly decreased （P〈0.05）, so it has shown that the cell cycle was probably blocked in G0/G1 stage. After intervention with ART at 20 and 80 μg/ml for 48 h, cellular apoptosis rate respectively was （36.42±0.77）% and （11.77±0.58）%, and the difference was statistically significant compared with the control （[6.64±0.191%, P〈0.01）. The expression of Cox-2 mRNA in the ART group was lower than those of control group, yet the expression of Caspase-3 and E-Cadherin mRNA in the ART group was higher than those of control group. Conclusion： ART can inhibit HEC-1B cell growth and proliferation in a dose- and time-dependent manner. Furthermore, ART can induce apoptosis in a dose-dependent manner. ART is able to downregulate Cox-2 mRNA expression and to upregulate E-Cadherin and Caspase-3 mRNA expression. So we can conclude that ART could induce the endometrial carcinoma HEC-1B cell apoptosis and inhibit tumor cell proliferation.展开更多
基金This work was supported by the National Natural Science Foundation （30225018） National Key Basic Research Program of China （2002CB513101）.
文摘Attrora-A kinase, a serine/threonine protein kinase, is a potential oncogene. Amplification and overexpression of Aurora-A have been found in several types of human tumors, including esophageal squamous cell carcinoma （ESCC）. It has been demonstrated that cells overexpressing Attrora-A are more resistant to cisplatin-induced apoptosis. However, the molecular mechanisms mediating these effects remain largely unknown. In this report, we showed that overexpression of Attrora-A through stable transfection of pEGFP-Aurora-A in human ESCC KYSE150 cells significantly promoted cell proliferation and inhibited cisplatin- or UV irradiation-induced apoptosis. Cleavages of caspase-3 and poly （ADPribose） polymerase （PARP） in Attrora-A overexpressing cells were substantially reduced after cisplatin or UV treatment. Furthermore, we found that silencing of endogenous Aurora-A kinase with siRNA substantially enhanced sensitivity to cisplatin- or UV-induced apoptosis in human ESCC EC9706 cells. In parallel, overexpression of Aurora-A potently upregulated the expression of Bcl-2. Moreover, the knockdown of Bcl-2 by siRNA abrogated the Aurora-A＇s effect on inhibiting apoptosis. Taken together, these data provide evidence that Aurora-A overexpression promoting cell proliferation and inhibiting apoptosis, suggesting a novel mechanism that is closely related to malignant phenotype and anti-cancer drugs resistance of ESCC cells.
文摘Objective： To observe the effect of the artesunate （ART） on cellular proliferation in vitro, to search for the possible anti-tumor mechanism of ART on endometrial carcinoma at the molecular level and to provide the experimental and theoretical foundations for the clinical applications of ART. Methods： The cell proliferation was observed by microscope; MTT was used to examine the effects of ART on proliferation of HEC-1B cells, and flow cytometric analysis was used to detect cell cycle and apoptosis. The human endometrial carcinoma HEC-1B cells were conventionally cultured; ART was administered with a concentration of 40 μg/ml before the total RNA were extracted, mRNA expression of Survivin, Caspase-3, N-Cadherin, E-Cadherin, Fibronectinl and Cox-2 were detected using RT-PCR. Results： ART reduced proliferation in human endometrial carcinoma cell line HEC-1B in a dose- and time-dependent effect. The cells of G0/G1 stage were significantly increased （P〈0.05）, but the cells of G2/M stages were significantly decreased （P〈0.05）, so it has shown that the cell cycle was probably blocked in G0/G1 stage. After intervention with ART at 20 and 80 μg/ml for 48 h, cellular apoptosis rate respectively was （36.42±0.77）% and （11.77±0.58）%, and the difference was statistically significant compared with the control （[6.64±0.191%, P〈0.01）. The expression of Cox-2 mRNA in the ART group was lower than those of control group, yet the expression of Caspase-3 and E-Cadherin mRNA in the ART group was higher than those of control group. Conclusion： ART can inhibit HEC-1B cell growth and proliferation in a dose- and time-dependent manner. Furthermore, ART can induce apoptosis in a dose-dependent manner. ART is able to downregulate Cox-2 mRNA expression and to upregulate E-Cadherin and Caspase-3 mRNA expression. So we can conclude that ART could induce the endometrial carcinoma HEC-1B cell apoptosis and inhibit tumor cell proliferation.
