Gnaphalium oxyphyllum DC is a medicinal plant whose common uses by Mexican people include the treatment of cancer. The toxicity of the aqueous and organic fractions as well as the aqueous decoction of G. oxyphyllum va...Gnaphalium oxyphyllum DC is a medicinal plant whose common uses by Mexican people include the treatment of cancer. The toxicity of the aqueous and organic fractions as well as the aqueous decoction of G. oxyphyllum var. natalie F. J. Espinosa were assessed on three human cancer cell lines as well as in blood cells in healthy human lymphocyte cultures. Cytotoxic activity was assessed by the Sulforhodamine B method on HeLa （human cervical carcinoma）, T47D （human breast carcinoma） and 22Rvl （human prostate carcinoma cancer）. Colchicine was used as positive control. The decoction was also tested on lymphocytes from healthy donors through the mitotic index as biomarker. We used whole blood for these cultures and estimated the effect of the extract on platelets, leukocytes and erythrocytes. The aqueous decoction was cytotoxic （EDs0 〈 20 μg/mL） on the three cancer cell lines. The mitotic index in the exposed lymphocyte cultures did not significantly differ from the control nor the blood counts showed any difference between the experimental and control cultures. These results prove that the toxic effect of the aqueous decoction of G. oxyphyllum var. natalie is specific for cancer cell lines.展开更多
Safe and efficient gene transfer systems are the basis of gene therapy applications. Non-integrating lentiviral(NIL) vectors are among the most promising candidates for gene transfer tools, because they exhibit high t...Safe and efficient gene transfer systems are the basis of gene therapy applications. Non-integrating lentiviral(NIL) vectors are among the most promising candidates for gene transfer tools, because they exhibit high transfer efficiency in both dividing and non-dividing cells and do not present a risk of insertional mutagenesis. However, non-integrating lentiviral vectors cannot introduce stable exogenous gene expression to dividing cells, thereby limiting their application. Here, we report the design of a non-integrating lentiviral vector that contains the minimal scaffold/matrix attachment region(S/MAR) sequence(SNIL), and this SNIL vector is able to retain episomal transgene expression in dividing cells. Using SNIL vectors, we detected the expression of the eGFP gene for 61 days in SNIL-transduced stable CHO cells, either with selection or not. In the NIL group without the S/MAR sequence, however, the transduced cells died under selection for the transient expression of NIL vectors. Furthermore,Southern blot assays demonstrated that the SNIL vectors were retained extrachromosomally in the CHO cells. In conclusion,the minimal S/MAR sequence retained the non-integrating lentiviral vectors in dividing cells, which indicates that SNIL vectors have the potential for use as a gene transfer tool.展开更多
文摘Gnaphalium oxyphyllum DC is a medicinal plant whose common uses by Mexican people include the treatment of cancer. The toxicity of the aqueous and organic fractions as well as the aqueous decoction of G. oxyphyllum var. natalie F. J. Espinosa were assessed on three human cancer cell lines as well as in blood cells in healthy human lymphocyte cultures. Cytotoxic activity was assessed by the Sulforhodamine B method on HeLa （human cervical carcinoma）, T47D （human breast carcinoma） and 22Rvl （human prostate carcinoma cancer）. Colchicine was used as positive control. The decoction was also tested on lymphocytes from healthy donors through the mitotic index as biomarker. We used whole blood for these cultures and estimated the effect of the extract on platelets, leukocytes and erythrocytes. The aqueous decoction was cytotoxic （EDs0 〈 20 μg/mL） on the three cancer cell lines. The mitotic index in the exposed lymphocyte cultures did not significantly differ from the control nor the blood counts showed any difference between the experimental and control cultures. These results prove that the toxic effect of the aqueous decoction of G. oxyphyllum var. natalie is specific for cancer cell lines.
基金supported by the Major State Basic Research Development Program of China(2011CB965203)
文摘Safe and efficient gene transfer systems are the basis of gene therapy applications. Non-integrating lentiviral(NIL) vectors are among the most promising candidates for gene transfer tools, because they exhibit high transfer efficiency in both dividing and non-dividing cells and do not present a risk of insertional mutagenesis. However, non-integrating lentiviral vectors cannot introduce stable exogenous gene expression to dividing cells, thereby limiting their application. Here, we report the design of a non-integrating lentiviral vector that contains the minimal scaffold/matrix attachment region(S/MAR) sequence(SNIL), and this SNIL vector is able to retain episomal transgene expression in dividing cells. Using SNIL vectors, we detected the expression of the eGFP gene for 61 days in SNIL-transduced stable CHO cells, either with selection or not. In the NIL group without the S/MAR sequence, however, the transduced cells died under selection for the transient expression of NIL vectors. Furthermore,Southern blot assays demonstrated that the SNIL vectors were retained extrachromosomally in the CHO cells. In conclusion,the minimal S/MAR sequence retained the non-integrating lentiviral vectors in dividing cells, which indicates that SNIL vectors have the potential for use as a gene transfer tool.
