Synthesis and biological evaluation of novel benzo[c]acridine-diones as potential anticancer agents and tubulin polymerization inhibitors.

A new series of novel benzo[c]acridine-diones possessing pharmacophoric elements of antitubulins with central dihydropyridine bridge were designed and synthesized as potential anticancer agents and tubulin polymerization inhibitors. The cytotoxic activity of the synthesized compounds was evaluated against eight cancer cell lines including MCF-7, A2780, HeLa, HepG2, DU145, A549, PC3, and LNCAP cancer cells and normal cells human umbilical vein endothelial cell (HUVEC) through 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, wherein ß-lapachone and combretastatin A-4 were used as positive controls. Some of our compounds (4c and 4g) showed significant cytotoxic activity on cancer cells with IC50 values in the range of 5.23-24.32 µM. None of the synthesized compounds showed significant cytotoxicity on normal HUVEC cells. Among all investigated derivatives, compound 4g showed promising greater antiproliferative activity against all tested cancer cells with the highest sensitivity observed for the PC3 cell line. Results from the flow cytometry analysis of PC3 and MCF-7 cancer cells treated with 4g showed an induced cell-cycle arrest at G2/M, and therefore induced apoptosis which occurred at low concentration of test compound, whereas annexin V-FITC/propidium iodide staining assay in the aforementioned cancer cell lines treated with 4g showed that 4g can cause necrosis in PC3 and MCF-7 cancer cells at higher concentration. Compound 4g proved to be an inhibitor of tubulin polymerization in a mode similar to that of colchicine and in a dose-dependent manner. Molecular docking studies of 4g into the colchicine-binding site of tubulin exhibited a possible mode of interaction between this compound and tubulin.

Synthesis and biological evaluation of benzo[b]furo[3,4-e][1,4]diazepin-1-one derivatives as anti-cancer agents.

A new series of novel Podophyllotoxin-like benzo[b]furo[3,4-e][1,4]diazepin-1-ones possessing structural elements of 4-aza-2,3-didehydropodophyllotoxins with central diazepine ring was designed and synthesized as anti-cancer agents. In initial assessment, the cytotoxic activity of the synthesized compounds was evaluated against three cancer cell lines including MCF-7, PC3 and B16-F10 employing the MTT assay. Some of compounds (12h, 13a, 13c and 14b) showed significant cytotoxic activity. So, we investigated the cytotoxicity of compounds 12h, 13a, 13c and 14b, along with podophyllotoxin as the reference drug in different cancer cell lines including A549, A2780, DU145, HeLa, and normal Huvec cell line. Among these four compounds, 13c showed promising antiproliferative activity against all cancer cells stronger than the other compounds and comparable to reference drug podophyllotoxin in some cancer cells. All these four compounds did not show significant cytotoxicity on normal Huvec cell line. The flow cytometry analysis of the MCF-7, PC3 and A2780 human cancer cell lines treated with 13c showed that 13c, induced apoptosis in the MCF-7, PC3 and A2780 human cancer cell lines, which is in good agreement to its cytotoxic activity as well. Compound 13c did not show significant influence on tubulin assembly and exert its cytotoxic effects via induction of apoptosis and has potent and selective cytotoxic effects in cancer cells.