XXXX alters chemosensitivity of @entity0 cells to @entity632 .

@entity632 @entity1 @entity58000 @entity522 @entity0 @entity70657 @entity5 @entity4404 @entity584 @entity98 @entity43765 @entity983 @entity10412 @entity3105
BACKGROUND: @entity0 remains a major health problem worldwide, and is becoming increasingly resistant to traditional drug treatments. For instance, @entity632 ( @entity3105 ) is beneficial for the treatment of @entity0 . However, its wide application often leads to drug resistance in clinic practice, which results in treatment failure. @entity70657 ( @entity58000 ), a polyprenylated @entity43765 isolated from the traditional medicine gamboge, has been reported to effectively inhibit the survival and proliferation of @entity5 cells. Its effects on @entity3105 resistance have not yet been reported in @entity0 . In this study, we examined the ability of @entity58000 to modulate @entity3105 resiatance and the molecular mechanisms underlying this process using a cell based in vitro system. METHODS: An @entity98 assay was used to evaluate the inhibitory effect of the drugs on the growth of MCF-7 and MCF-7/ @entity3105 cell lines. The effects of drugs on apoptosis were detected using @entity4404 APC/7-AAD double staining. The expression of apoptosis-related proteins and the proteins in the @entity983 / @entity10412 / @entity584 pathway were evaluated by Western blot analysis. RESULTS: In the MCF-7/ @entity3105 cell lines, the IC50 (half maximal inhibitory concentration) of the group that received combined treatment with @entity58000 and @entity3105 was significantly lower than that in the @entity3105 group, and this value decreased with an increasing concentration of @entity58000 . In parallel, @entity58000 treatment increased the chemosensitivity of @entity0 cells to @entity3105 . The cell apoptosis and cell cycle anaysis indicated that the anti-proliferative effect of @entity58000 is in virtue of increased G0/G1 arrest and potentiated apoptosis. When combined with @entity58000 in MCF-7/ @entity3105 cell lines, the expression levels of the @entity5 suppressor gene @entity983 (phosphatase and tensin homolog deleted on chromosome ten) and the apoptosis-related proteins @entity522 and capsese-9 were significantly increased, while the expression of phosphorylated @entity584 was decreased. CONCLUSIONS: Our study has indicated a potential role for @entity58000 to increase the chemosensitivity of @entity0 cells to @entity3105 . This modulatory role was mediated by suppression of the @entity983 / @entity10412 / @entity584 pathway that led to apoptosis in MCF-7/ @entity3105 cells. This work suggests that @entity58000 may be used as a regulatory agent for treating @entity3105 resistance in @entity0 @entity1 .
