MATERIALS AND METHODS: MCF-7 cells were plated at a density of 15105 cells/well in 6-well plates. After 24h, cells were treated with a series of concentrations of rapamycin while only adding DMEM medium with PEG for the control regiment and grown at 37oC, 5% CO2 and 95% air for 72h. Trypan blue was used to determine the cell viability and proliferation. Untreated and rapamycin-treated MCF-7 cells were also examined for morphological changes with an inverted-phase contrast microscope. Alteration in cell morphology was ascertained, along with a stage in the cell cycle and proliferation. In addition, cytotoxicity testing was performed using normal mouse breast mammary pads.
RESULTS: Our results clearly showed that rapamycin exhibited inhibitory activity on MCF-7 cell lines. The IC50 value of rapamycin on the MCF-7 cells was determined as 0.4μg/ml (p<0.05). Direct observation by inverted microscopy demonstrated that the MCF-7 cells treated with rapamycin showed characteristic features of apoptosis including cell shrinkage, vascularization and autophagy. Cells underwent early apoptosis up to 24% after 72h. Analysis of the cell cycle showed an increase in the G0G1 phase cell population and a corresponding decrease in the S and G2M phase populations, from 81.5% to 91.3% and 17.3% to 7.9%, respectively.
CONCLUSIONS: This study demonstrated that rapamycin may potentially act as an anti-cancer agent via the inhibition of growth with some morphological changes of the MCF-7 cancer cells, arrest cell cycle progression at G0/G1 phase and induction of apoptosis in late stage of apoptosis. Further studies are needed to further characterize the mode of action of rapamycin as an anti-cancer agent.
BACKGROUND: Few data regarding the safety and effectiveness of self-apposing sirolimus-eluting Stentys stent are available.
METHODS: 278 patients (30% stable coronary artery disease, 70% acute coronary syndromes, and 54% on unprotected left main) treated with sirolimus eluting Stentys stent were retrospectively included in the self-aPposing, bAlloon-delivered, siRolimus-eluting stent for the Treatment of the coronary Artery disease multicenter registry. Major adverse cardiovascular events (MACE, a composite of cardiac death, myocardial infarction, target lesion revascularization, stent thrombosis) were the primary end-point, single components of MACE were the secondary ones.
RESULTS: After 13 months (interquartile range 5-32), MACE was 14%. Stent thrombosis occurred in 3.9% of the patients (2.5% definite stent thrombosis and 1.4% probable stent thrombosis), 66% of them presenting with ST-segment elevation myocardial infarction (STEMI) at admission. Cardiovascular death, target lesion revascularization and myocardial infarction was 4.7%, 8.3%, and 7.2%, respectively. At multivariate analysis, risk of MACE was increased by diabetes (hazard ratios 4.76; P = 0.002) but was not affected by the indication leading to sirolimus-eluting Stentys stent implantation (marked vessel tapering vs. coronary ecstasies, hazard ratios 0.74, P = 0.71).
CONCLUSION: Sirolimus-eluting Stentys stent may represent a potential solution for specific coronary anatomies such as bifurcation, ectasic, or tapered vessels. Risk of stent thrombosis appears related to clinical presentation with STEMI and to anatomic features, stressing the importance of the use of intracoronary imaging for self-expandable stents implantation.
METHODS: By utilizing a panel of breast cancer cells and mammospheres culture as cell-based screening platforms, we performed high-throughput chemical library screens to identify agents that are effective against breast CSCs and non-CSCs. The hit molecules were paired with conventional chemotherapy to evaluate the combinatorial treatment effects on breast CSCs and non-CSCs.
RESULTS: We identified a total of 193 inhibitors that effectively targeting both breast CSCs and non-CSCs. We observed that histone deacetylase inhibitors (HDACi) synergized conventional chemotherapeutic agents (i.e., doxorubicin and cisplatin) in targeting breast CSCs and non-CSCs simultaneously. Further analyses revealed that quisinostat, a potent inhibitor for class I and II HDACs, potentiated doxorubicin-induced cytotoxicity in both breast CSCs and non-CSCs derived from the basal-like (MDA-MB-468 and HCC38), mesenchymal-like (MDA-MB-231), and luminal-like breast cancer (MCF-7). It was also observed that the basal-like breast CSCs and non-CSCs were more sensitive to the co-treatment of quisinostat with doxorubicin compared to that of the luminal-like breast cancer subtype.
CONCLUSION: In conclusion, this study demonstrates the potential of HDACi as therapeutic options, either as monotherapy or in combination with chemotherapeutics against refractory breast cancer.