Salinomycin（SAL）,a polyether antibiotic isolated from Streptomyces albus,is widely used as an anticoccidial drug in poultry and other livestock and is furthermore fed to ruminescent animals to improve nutrient absor...Salinomycin（SAL）,a polyether antibiotic isolated from Streptomyces albus,is widely used as an anticoccidial drug in poultry and other livestock and is furthermore fed to ruminescent animals to improve nutrient absorption and feed efficiency.It has recently been shown to act as a specific inhibitor of cancer stem cells.At present,the price of salinomycin sodium（SAL-Na） is 10 fold lower than that of salinomycin,however,there is no report about the comparison of the inhibitory effects of SAL and SAL-Na on cancer stem cells as well as cancer cells.In the present study,side population cells（SP cells）and non-SP cells （NSP cells）sorted from human breast cancer cell line MCF-7 were chosen as the models of cancer stem cells and cancer cells, respectively.SRB assay was performed to compare the cytotoxicity of SAL and SAL-Na.First of all,SP cells were sorted from MCF-7 cells via FACSDiva flow cytometry.Secondly,the sorted SP cells were identified with the surface makers（CD44~＋/CD24^-） of breast cancer stem cells.Finally,the inhibitory effects of SAL and SAL-Na were evaluated on the sorted SP cells and NSP cells.Results showed that,as compared to breast cancer cells,the inhibitory effect of free SAL or free SAL-Na was more potent in breast cancer stem cells.Furthermore,the inhibitory effects of free SAL and free SAL-Na had no significant difference for the SP cells as well as the NSP cells when they were in the same concentration.Thus,it suggested that salinomycin sodium should be considered as a potential candidate to take the place of salinomycin in cancer stem cells research,due to their similar inhibitory effects on cancer stem cells.展开更多
Salinomycin sodium（SAL-Na） is a type of antibiotic chemotherapeutic drugs with the potential to treat cancer stem cells. The assay method of SAL-Na included in the pharmacopoeia is a microbiological method, which is...Salinomycin sodium（SAL-Na） is a type of antibiotic chemotherapeutic drugs with the potential to treat cancer stem cells. The assay method of SAL-Na included in the pharmacopoeia is a microbiological method, which is not suitable for the rapid detection in daily scientific research. Besides, the assay methods of SAL-Na reported by literature are not suitable for quantification due to the interference of various excipients. Consequently, the deep study on biological mechanism of SAL-Na is hindered by its assay method. In the present study, we aimed to establish an ultraviolet visible（UV-vis） spectrophotometric method to determine the content of SAL-Na in the liposomes. The first approach was a UV spectrophotometry, in which SAL-Na was dissolved in ethanol and then detected at 287 nm. Although the standard curve measured at 287 nm by UV method had good linearity, the quantification limitation was too high to meet the requirement in determining SAL-Na in the liposomes. In addition, the membrane materials in the liposomes severely affected the measurement. The second one was an improved UV-vis spectrophotometry by vanillin derivatization. In this method, SAL-Na was dissolved in 95% ethanol, mixed with vanillin test solution and heated at 72 ℃ for 40 min for derivatization. After cooling down to room temperature, the solution was detected using UV-vis spectrophotometer at 526 nm. This method could be used to accurately determine the content of SAL-Na at lower concentration, and the absorbance value was stable for 5 d at least. Moreover, the membrane materials of the liposomes did not affect the absorbance of SAL-Na at 526 nm. The precision and recovery studies demonstrated that the vanillin derivatization approach was stable and precise in assaying SAL-Na. In conclusion, the UV-vis spectrophotometry by vanillin derivatization could be used for measuring SAL-Na in the liposomes, thereby laying a foundation for deep study of the biological mechanism of SAL-Na in the liposomes.展开更多
基金National Basic Research Program of China(Grant No 2009CB930300)State Key Projects(Grant No 2009ZX093 10- 001)the 863 Project(GrantNo 2007AA021811)
文摘Salinomycin（SAL）,a polyether antibiotic isolated from Streptomyces albus,is widely used as an anticoccidial drug in poultry and other livestock and is furthermore fed to ruminescent animals to improve nutrient absorption and feed efficiency.It has recently been shown to act as a specific inhibitor of cancer stem cells.At present,the price of salinomycin sodium（SAL-Na） is 10 fold lower than that of salinomycin,however,there is no report about the comparison of the inhibitory effects of SAL and SAL-Na on cancer stem cells as well as cancer cells.In the present study,side population cells（SP cells）and non-SP cells （NSP cells）sorted from human breast cancer cell line MCF-7 were chosen as the models of cancer stem cells and cancer cells, respectively.SRB assay was performed to compare the cytotoxicity of SAL and SAL-Na.First of all,SP cells were sorted from MCF-7 cells via FACSDiva flow cytometry.Secondly,the sorted SP cells were identified with the surface makers（CD44~＋/CD24^-） of breast cancer stem cells.Finally,the inhibitory effects of SAL and SAL-Na were evaluated on the sorted SP cells and NSP cells.Results showed that,as compared to breast cancer cells,the inhibitory effect of free SAL or free SAL-Na was more potent in breast cancer stem cells.Furthermore,the inhibitory effects of free SAL and free SAL-Na had no significant difference for the SP cells as well as the NSP cells when they were in the same concentration.Thus,it suggested that salinomycin sodium should be considered as a potential candidate to take the place of salinomycin in cancer stem cells research,due to their similar inhibitory effects on cancer stem cells.
基金National Science Foundation of China(Grant No.81673367)
文摘Salinomycin sodium（SAL-Na） is a type of antibiotic chemotherapeutic drugs with the potential to treat cancer stem cells. The assay method of SAL-Na included in the pharmacopoeia is a microbiological method, which is not suitable for the rapid detection in daily scientific research. Besides, the assay methods of SAL-Na reported by literature are not suitable for quantification due to the interference of various excipients. Consequently, the deep study on biological mechanism of SAL-Na is hindered by its assay method. In the present study, we aimed to establish an ultraviolet visible（UV-vis） spectrophotometric method to determine the content of SAL-Na in the liposomes. The first approach was a UV spectrophotometry, in which SAL-Na was dissolved in ethanol and then detected at 287 nm. Although the standard curve measured at 287 nm by UV method had good linearity, the quantification limitation was too high to meet the requirement in determining SAL-Na in the liposomes. In addition, the membrane materials in the liposomes severely affected the measurement. The second one was an improved UV-vis spectrophotometry by vanillin derivatization. In this method, SAL-Na was dissolved in 95% ethanol, mixed with vanillin test solution and heated at 72 ℃ for 40 min for derivatization. After cooling down to room temperature, the solution was detected using UV-vis spectrophotometer at 526 nm. This method could be used to accurately determine the content of SAL-Na at lower concentration, and the absorbance value was stable for 5 d at least. Moreover, the membrane materials of the liposomes did not affect the absorbance of SAL-Na at 526 nm. The precision and recovery studies demonstrated that the vanillin derivatization approach was stable and precise in assaying SAL-Na. In conclusion, the UV-vis spectrophotometry by vanillin derivatization could be used for measuring SAL-Na in the liposomes, thereby laying a foundation for deep study of the biological mechanism of SAL-Na in the liposomes.
