The outcomes of chemotherapy have been unsatisfactory with the palpable side effects. We hypothesized that natural products might help improve chemotherapy with few side effects. Recently, we came across the bioactive...The outcomes of chemotherapy have been unsatisfactory with the palpable side effects. We hypothesized that natural products might help improve chemotherapy with few side effects. Recently, we came across the bioactive extracts of monk fruit (Siraitia grosvenori) with anticancer activity. We then investigated if these extracts might have chemosensitizing effect to improve the efficacy of drugs clinically used today. Four different drugs, cisplatin (CPL), carboplatin (CBL), mitomycin C (MMC), and gemcitabine (GEM), were used in this study. Human bladder cancer T24 cells were treated with each drug itself or drug combined with either LLE or MOG (two types of monk fruit extracts). Cell viability was determined to assess anticancer effect and also explored the anticancer mechanism of such combinations, focusing on the status of glycolysis, cell cycle, and chromatin structure. Cell viability test showed that all drugs had anticancer activity, reducing cell viability, but only CPL showed the enhanced anticancer effect when combined with LLE (not with MOG). The rest of three drugs had no such effects with LLE or MOG. The CPL/LLE combination was found to disrupt glycolysis, by inhibiting hexokinase activity, resulted in the decreased ATP synthesis. This combination also blocked the cell cycle progression, due to a G1 cell cycle arrest. Moreover, the two epigenetic regulators, DNA methyltransferase and histone deacetylase, were inactivated with the combination, indicating chromatin modifications. Ultimately, these treated cells were found to undergo apoptosis. In conclusion, anticancer activity of CPL can be significantly enhanced with LLE. This chemosensitizing effect is attributed to the glycolysis inhibition, a G1 cell cycle arrest, and chromatin modifications, ultimately leading to apoptosis. Thus, certain natural products such as LLE could be used as an adjuvant agent in current chemotherapy, improving the drug efficacy but minimizing side effects.展开更多
文摘The outcomes of chemotherapy have been unsatisfactory with the palpable side effects. We hypothesized that natural products might help improve chemotherapy with few side effects. Recently, we came across the bioactive extracts of monk fruit (Siraitia grosvenori) with anticancer activity. We then investigated if these extracts might have chemosensitizing effect to improve the efficacy of drugs clinically used today. Four different drugs, cisplatin (CPL), carboplatin (CBL), mitomycin C (MMC), and gemcitabine (GEM), were used in this study. Human bladder cancer T24 cells were treated with each drug itself or drug combined with either LLE or MOG (two types of monk fruit extracts). Cell viability was determined to assess anticancer effect and also explored the anticancer mechanism of such combinations, focusing on the status of glycolysis, cell cycle, and chromatin structure. Cell viability test showed that all drugs had anticancer activity, reducing cell viability, but only CPL showed the enhanced anticancer effect when combined with LLE (not with MOG). The rest of three drugs had no such effects with LLE or MOG. The CPL/LLE combination was found to disrupt glycolysis, by inhibiting hexokinase activity, resulted in the decreased ATP synthesis. This combination also blocked the cell cycle progression, due to a G1 cell cycle arrest. Moreover, the two epigenetic regulators, DNA methyltransferase and histone deacetylase, were inactivated with the combination, indicating chromatin modifications. Ultimately, these treated cells were found to undergo apoptosis. In conclusion, anticancer activity of CPL can be significantly enhanced with LLE. This chemosensitizing effect is attributed to the glycolysis inhibition, a G1 cell cycle arrest, and chromatin modifications, ultimately leading to apoptosis. Thus, certain natural products such as LLE could be used as an adjuvant agent in current chemotherapy, improving the drug efficacy but minimizing side effects.
