ABSTRACT
Objective To investigate the multidrug-resistance reversal action and mechanism of dihydroartemisin (DHA) on human colon cancer cell line HCT8/ADR. Methods The cytotoxicity of dihydroartemisin combined with doxorubicin(DOX) was determined by methyl thiazolyl tetrazolium(MTT) assay and cell apoptosis was observed by flow cytometry. Western blot assay was used to measure the autophagy. Results The combined treatment with dihydroartemisin and doxorubicin significantly enhanced the cytotoxicity in HCT8/ADR cells and effectively increased the apoptotic level. Autophagy was also induced by the combined treatment , which maybe played a crucial role in the regulation of doxorubicin-sensitization of HCT8/ADR cells. Conclusion The results indicated that dihydroartemisin can reverse multidrug resistance through increasing the doxorubicin-sensitivity of HCT8/ADR cells.
ABSTRACT
Objective To investigate the anti-tumor activities of cell-penetrating peptide ( CPP) - mediated trichosanthin ( TCS) , which is a recombinant protein obtained from Radix Trichosanthis. Methods Cysteine residue was introduced to the C-terminus of TCS by protein recombinant technique, and then with the newly-formed terminal as the modification site, TCS was coupled with CPP. As a target protein, CPP-mediated TCS was isolated and purified by affinity chromatography. The expression of the target protein and its responsiveness to reducing substances were detected by using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The cellular uptake rate of CPP-mediated TCS was determined by using cell uptake test, and its anti-tumor activity was measured by using methyl thiazolyl tetrazolium (MTT) assay. Results The TCS-CPP compound had been successfully developed in this study, and showed certain reducing responsiveness. After modified with CPP, TCS had higher cellular uptake rate and stronger anti-tumor effect on HeLa and MCF-7 cells. Conclusion TCS modified by CPP can enhance the anti-tumor activities of TCS.