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.
METHODS: The Multinational Abluminal Sirolimus Coated BiO-Engineered StenT (MASCOT) registry was a prospective post-marketing study conducted from June 2014-May 2017 across 60 centers globally. Patients were eligible if COMBO stent implantation was attempted, and they received dual antiplatelet therapy (DAPT) per local guidelines. Follow-up was conducted by trained research staff at 1, 6 and 12 months by phone or clinic visit to capture clinical events and DAPT cessation events. The primary endpoint was 1-year target lesion failure (TLF), composite of cardiac death, non-fatal myocardial infarction not clearly attributable to a non-target vessel, or ischemia-driven target lesion revascularization.
RESULTS: A total of 2614 patients were enrolled over the study period with 96.7% completion of 1-year follow-up. The mean age of enrolled patients was 62.9 ± 11.2 years and 23.0% were female. Diabetes mellitus was present at baseline in 33.5%. A total of 56.1% patients underwent PCI for acute coronary syndrome (ACS). The 1-year primary endpoint of TLF occurred in 3.4% patients (n = 88). Definite stent thrombosis occurred in 0.5% patients (n = 12).
CONCLUSION: The MASCOT post marketing registry provides comprehensive safety and efficacy outcomes following contemporary PCI using the novel COMBO stent in an all-comer population. This platform is associated with low rates of 1-year TLF and ST. CLINICALTRIALS.
GOV IDENTIFIER: NCT02183454.
MATERIALS AND METHODS: Thirty five female Sprague Dawley rats at age 21-day old were divided into 4 groups; Group 1 (control, n=10), Group 2 (PF4, n=5), Group 3 (rapamycin, n=10) and Group 4 (rapamycin+PF4, n=10). MNU was administered intraperitionally, dosed at 70 mg/kg body weight. The rats were treated when the tumors reached the size of 14.5 ± 0.5 mm and subsequently sacrificed after 5 days. Rapamycin and PF4 were administered as focal intralesional injections at the dose of 20 μg/lesion. The tumor tissue was then subjected to histopathological examinations for morphological appraisal and immunohistochemical assessment of the pro-apoptotic marker, Bax and anti-apoptotic markers, Bcl-2 and survivin.
RESULTS: The histopathological pattern of the untreated control cohort showed that the severity of the malignancy augments with mammary tumor growth. Tumors developing in untreated groups were more aggressive whilst those in treated groups demonstrated a transformation to a less aggressive subtype. Combined treatment resulted in a significant reduction of tumor size without phenotypic changes. Bax, the pro-apoptotic marker, was significantly expressed at higher levels in the rapamycin-treated and rapamycin+PF4-treated groups compared to controls (p<0.05). Consequently, survivin was also significantly downregulated in the rapamycin-treated and rapamycin+PF4-treated group and this was significantly different when compared to controls (p).
CONCLUSIONS: In our rat model, it could be clearly shown that rapamycin specifically affects Bax and survivin signaling pathways in activation of apoptosis. We conclude that rapamycin plays a critical role in the induction of apoptosis in MNU-induced mammary carcinoma.