Currently,drug resistance of anti-cancer therapy has become the main cause of low survival rate and poor prognosis.Full understanding of drug resistance mechanisms is an urgent request for further development of anti-...Currently,drug resistance of anti-cancer therapy has become the main cause of low survival rate and poor prognosis.Full understanding of drug resistance mechanisms is an urgent request for further development of anti-cancer therapy and improve-ment of prognosis.Here we present our N-glycoproteomics study of putative N-glycoprotein biomarkers of drug resistance in doxorubicin resistance breast cancer cell line michigan cancer foundation-7(MCF-7/ADR)relative to parental michigan cancer foundation-7(MCF-7)cells.Intact N-glycopeptides(IDs)from MCF-7/ADR and MCF-7 cells were enriched with zwitterionic hydrophilic interaction liquid chromatography(ZIC-HILIC),labeled with stable isotopic diethylation(SIDE),and analyzed with C18-RPLC-MS/MS(HCD with stepped normalized collision energies);these IDs were identified with database search engine GPSeeker,and the differentially expressed intact N-glycopeptides(DEGPs)were quantified with GPSeekerQuan.With target-decoy searches and control of spectrum-level FDR≤1%,322 intact N-glycopeptides were identified;these intact N-glycopeptides come from the combination of 249 unique peptide backbones(corresponding to 234 intact N-glycoproteins)and 90 monosaccharide compositions(corresponding to 248 putative N-glycosites).The sequence structures of 165 IDs were confirmed with structure-diagnostic fragment ions.With the criteria of observation at least twice among the three technical replicates,≥1.5-fold change and p value<0.05,20 DEGPs were quantified,where five of them were up-regulated and 15 of them were down-regulated;the corresponding intact N-glycoproteins as putative markers of drug resistance were discussed.展开更多
Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], ...Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.展开更多
A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function ...A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector (pH Apr-1 neo) and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdrl mRNA expression by 83. 5 %; and the expressed ribozyme could inhibite the formation of p-glycoprotein detected by immuno- cy-tochemistry assay and could reduce the cell’s resistance to adrimycin; this means that the resistant cells were 1 000-fold more resistant than the parental cell line(MCF-7), whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype.展开更多
基金supported by National Natural Science Foundation of China(21775110,22074105)Shanghai Science and Technology Commission(14DZ2261100).
文摘Currently,drug resistance of anti-cancer therapy has become the main cause of low survival rate and poor prognosis.Full understanding of drug resistance mechanisms is an urgent request for further development of anti-cancer therapy and improve-ment of prognosis.Here we present our N-glycoproteomics study of putative N-glycoprotein biomarkers of drug resistance in doxorubicin resistance breast cancer cell line michigan cancer foundation-7(MCF-7/ADR)relative to parental michigan cancer foundation-7(MCF-7)cells.Intact N-glycopeptides(IDs)from MCF-7/ADR and MCF-7 cells were enriched with zwitterionic hydrophilic interaction liquid chromatography(ZIC-HILIC),labeled with stable isotopic diethylation(SIDE),and analyzed with C18-RPLC-MS/MS(HCD with stepped normalized collision energies);these IDs were identified with database search engine GPSeeker,and the differentially expressed intact N-glycopeptides(DEGPs)were quantified with GPSeekerQuan.With target-decoy searches and control of spectrum-level FDR≤1%,322 intact N-glycopeptides were identified;these intact N-glycopeptides come from the combination of 249 unique peptide backbones(corresponding to 234 intact N-glycoproteins)and 90 monosaccharide compositions(corresponding to 248 putative N-glycosites).The sequence structures of 165 IDs were confirmed with structure-diagnostic fragment ions.With the criteria of observation at least twice among the three technical replicates,≥1.5-fold change and p value<0.05,20 DEGPs were quantified,where five of them were up-regulated and 15 of them were down-regulated;the corresponding intact N-glycoproteins as putative markers of drug resistance were discussed.
文摘Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.
基金This research was supported by the National Natural ScienceYouth Grant.
文摘A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector (pH Apr-1 neo) and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdrl mRNA expression by 83. 5 %; and the expressed ribozyme could inhibite the formation of p-glycoprotein detected by immuno- cy-tochemistry assay and could reduce the cell’s resistance to adrimycin; this means that the resistant cells were 1 000-fold more resistant than the parental cell line(MCF-7), whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype.
基金Supported by National Science Fund Committee(30160098)Liaoning State of Education (2021001282)+1 种基金Guangdong Nature Science Fund (07117912)GuangdongState of Chinese Medicine (1060111)