Cytotoxic and apoptosis inducing effect of some pyrano [3, 2-c] pyridine derivatives against MCF-7 breast cancer cells.

Anti-cancer activities of some pyrano-pyridines have been previously reported. Herein, we investigated anti-proliferative and apoptotic effects of the novel pyrano [3, 2-c] pyridine (P.P, TPM.P, 4-CP.P and 3-NP.P) compounds against MCF-7 breast cancer cells. The MCF-7 cells were cultured in the presence of various concentrations (20-200 µM) of the tested compounds for 3 days and the cell viability was determined by MTT assay. Induction of apoptosis was qualitatively assayed by acridine orange/ethidium bromide (AO/EtBr) staining, DNA fragmentation assay, as well as quantitatively by Annexin V/PI double staining and cell cycle analysis. These compounds inhibited growth and proliferation of the MCF-7 cells in a dose- and time-dependent manner. The IC50 values of P.P, TPM.P, 4-CP.P and 3-NP.P after 24 h of exposure were calculated to be 100±5.0, 180±6.0, 60±4.0 and 140±5.0 µM, respectively. 4-CP.P was determined as the most potent compound and was chosen for further studies. The result of flow cytometric cell cycle analysis indicated an increase in sub-G1 population after 72 h treatment of the cells. Furthermore, this was accompanied by exposure of phosphatidylserine (PS) in the outer cell membrane after time course of treatment with the 4-CP.P. Based on these observations, the pyrano [3, 2-c] pyridines can be regarded as a valuable candidate for further pharmaceutical evaluations.

Apoptosis induction activity and molecular docking studies of survivin siRNA carried by Fe3O4-PEG-LAC-chitosan-PEI nanoparticles in MCF-7 human breast cancer cells.

Delivery of small interfering RNAs (siRNAs) into cells still remains a challenge in gene delivery studies. Here, we investigated the ability of synthesized Fe3O4-PEG-LAC-chitosan-PEI nanoparticles for siRNA delivery of survivin as the model gene into cells. The cellular uptake of survivin siRNA carried by synthesized nanoparticles into MCF-7 breast cancer cell line was evaluated by florescent microscopy and flowcytometry, both proving the efficacy of nanoparticles in delivery of up to 64.7% in comparison with lipofectamine 2000. Furthermore, the delivery of survivin siRNA by the nanoparticles (nanoplex) induced apoptosis that was assessed through DAPI staining and Annexin V/PI assays. In addition, we evaluated the efficacy of treatment with nanoplexes in the presence of mitoxantrone, as a chemotherapeutic agent. Our data indicated that inhibition of survivin expression increased the cell sensitivity to mitoxantrone. Real-time PCR and western blotting analysis revealed a significant reduction in mRNA and protein levels of survivin upon delivery of siRNA. Molecular docking studies showed that nanoparticles can bind to centeral BIR domain of survivin, exactly above zinc ion location with high affinity (ΔG: -10.3Kcal/mol). Also, thermodynamic studies proved the experimental results theoretically, revealing that the siRNA-loaded nanoparticles have a suppressing effect on survivin mRNA. Therefore, delivery of survivin siRNA into MCF-7 cells using Fe3O4-PEG-LAC-chitosan-PEI nanoparticles as a carrier enhances the cell death.