Objective:To analyse the expression of telomerase and apoptosis related protein,and explore the possible mechanism of breast cancer development.Methods:Immunohistochemistry method(SP)was used to detect the expression ...Objective:To analyse the expression of telomerase and apoptosis related protein,and explore the possible mechanism of breast cancer development.Methods:Immunohistochemistry method(SP)was used to detect the expression of hTERT,p53 and bcl-2 in the tissues of 48 cases of human breast cancer and 42 cases of benign lesions in breast.Results: The positive rates of expression of hTERT,p53 and bcl-2 in breast cancer were 87.50%,56.25%and 54.17%,respectively. Compared with the groups of adjacent noncancerous and benign lesions,there was a significant difference among three types of tissues(P<0.05).The positive rates of expression of p53 and bcl-2 in the group with positive expression of hTERT were 64.28%and 61.90%,respectively,and their difference was significant compared with the negative group(P<0.05). Conclusion:There is a correlation between the activation of telomerases and p53 gene mutation in the development of breast cancer,and they are perhaps relation to the down regulation of bcl-2.展开更多
The toxic effects of tributyltin（TBT） have been extensively documented in several types of cells, but the molecular mechanisms related to the genotoxic effects of TBT have still not been fully elucidated. Our study ...The toxic effects of tributyltin（TBT） have been extensively documented in several types of cells, but the molecular mechanisms related to the genotoxic effects of TBT have still not been fully elucidated. Our study showed that exposure of human hepatoma G2 cells to 1–4 μmol/L TBT for 3 hr caused severe DNA damage in a concentration-dependent manner. Moreover, the expression levels of key DNA damage sensor genes such as the replication factor C, proliferating cell nuclear antigen and poly（ADP-ribose）polymerase-1 were inhabited in a concentration-dependent manner. We further demonstrated that TBT induced cell apoptosis via the p53-mediated pathway, which was most likely activated by the ataxia telangiectasia mutated and rad-3 related（ATR）protein kinase. The results also showed that cytochrome c, caspase-3, caspase-8,caspase-9, and the B-cell lymphoma 2 were involved in this process. Taken together, we demonstrated for the first time that the inhibition of the DNA repair system might be more responsible for TBT-induced genotoxic effects in cells. Then the generated DNA damage induced by TBT initiated ATR-p53-mediated apoptosis.展开更多
基金a grant from the Foundation of Health Department ofHenan Province(No.20060038).
文摘Objective:To analyse the expression of telomerase and apoptosis related protein,and explore the possible mechanism of breast cancer development.Methods:Immunohistochemistry method(SP)was used to detect the expression of hTERT,p53 and bcl-2 in the tissues of 48 cases of human breast cancer and 42 cases of benign lesions in breast.Results: The positive rates of expression of hTERT,p53 and bcl-2 in breast cancer were 87.50%,56.25%and 54.17%,respectively. Compared with the groups of adjacent noncancerous and benign lesions,there was a significant difference among three types of tissues(P<0.05).The positive rates of expression of p53 and bcl-2 in the group with positive expression of hTERT were 64.28%and 61.90%,respectively,and their difference was significant compared with the negative group(P<0.05). Conclusion:There is a correlation between the activation of telomerases and p53 gene mutation in the development of breast cancer,and they are perhaps relation to the down regulation of bcl-2.
基金supported by the National Natural Science Foundation of China (No. 40606027)the Project of the Xiamen Science and Technology Program (No. 2013Z20134027)
文摘The toxic effects of tributyltin（TBT） have been extensively documented in several types of cells, but the molecular mechanisms related to the genotoxic effects of TBT have still not been fully elucidated. Our study showed that exposure of human hepatoma G2 cells to 1–4 μmol/L TBT for 3 hr caused severe DNA damage in a concentration-dependent manner. Moreover, the expression levels of key DNA damage sensor genes such as the replication factor C, proliferating cell nuclear antigen and poly（ADP-ribose）polymerase-1 were inhabited in a concentration-dependent manner. We further demonstrated that TBT induced cell apoptosis via the p53-mediated pathway, which was most likely activated by the ataxia telangiectasia mutated and rad-3 related（ATR）protein kinase. The results also showed that cytochrome c, caspase-3, caspase-8,caspase-9, and the B-cell lymphoma 2 were involved in this process. Taken together, we demonstrated for the first time that the inhibition of the DNA repair system might be more responsible for TBT-induced genotoxic effects in cells. Then the generated DNA damage induced by TBT initiated ATR-p53-mediated apoptosis.
