Anticancer Properties of a New Hybrid Analog AD-013 Combining a Coumarin Scaffold with an α-methylene-δ-lactone Motif

Background: Coumarin is a natural phytochemical but as such has no medical uses. However, various natural and synthetic coumarin analogs attract attention due to their interesting biological properties. Objective: Here, we evaluated and compared anticancer properties of a new synthetic hybrid compound AD- 013, which integrates a coumarin moiety and an α-methylene-δ-lactone motif, with novobiocin, a natural antibiotic bearing a coumarin scaffold. Methods: Cytotoxic activities of compound AD-013 and novobiocin were assessed by the MTT assay. In order to explore the mechanism of anticancer activity of analog AD-013, we performed quantitative real-time PCR analysis of apoptosis- and cell cycle-related genes. The ability of AD-013 and novobiocin to induce apoptosis and DNA damage was studied by flow cytometry. Results: The cytotoxic activity of this new compound was compared with the activity of a coumarin-based antibiotic novobiocin against two cancer cell lines, MCF-7 and HL-60 and also against normal human cells, MCF- 10A and HUVEC. AD-013 was much more cytotoxic than novobiocin in both cancer cell lines and showed some selectivity against MCF-7 cancer cells as compared with MCF-10A healthy cells. Expression levels of the pro-apoptotic genes significantly increased while the anti-apoptotic genes, were down-regulated for both compounds in both cancer cell lines. AD-013 was able to inhibit cell proliferation, generate DNA damage and induce apoptosis. The obtained data showed that this compound caused the cell cycle arrest in subG0/G1 in both cancer cell lines. Conclusion: The new hybrid analog was a much stronger apoptosis inducer than novobiocin and activated the intrinsic pathway of apoptosis.