Synthesis and Apoptotic Activities of New 2(3H)-benzoxazolone Derivatives in Breast Cancer Cells

Abstract

Background: 2(3H)-Benzoxazolone derivatives are preferential structural blocks in pharmacological probe designing with the possibility of modifications at various positions on the core structure. Benzoxazolones showed various biological activities such as analgesics, anti-inflammatory and anti-cancer.

Objective: In the present work, we have prepared new Mannich bases of 2(3H)-benzoxazolone derivatives and evaluated their cytotoxicities and proapoptotic properties in MCF-7 breast cancer cell line.

Methods: The structures of these compounds were characterized by FT-IR, elemental analysis, 1H and 13C NMR. Cytotoxicities of all the target compounds were investigated by MTT assay. Apoptotic properties of compounds were evaluated by immunocytochemistry using antibodies against caspase-3, cytochrome-c, FasL, and also TUNEL assay.

Results: These two novel compounds, 1 and 2, both have the same piperazine substituent on the nitrogen atom of benzoxazolone and the main difference in the structures of these compounds is the presence of Cl substituent at the 5- position of the benzoxazolone ring. MTT results showed that compounds 1 and 2 were effective in terms of reduction of cell viability at 100μM and 50μM concentration for 48h, respectively. As a result of immunohistochemical staining, Fas L and caspase-3 immunoreactivities were significantly increased in MCF-7 cells after treatment with compound 1. Additionally, caspase-3 and cytochrome-c immunoreactivities were also increased significantly in MCF-7 cells after treatment with compound 2. The number of TUNEL positive cells was significantly higher in MCF-7 cells when compared with the control group after treatment with both compounds 1 and 2.

Conclusion: It could be concluded that N-substituted benzoxazolone derivatives increase potential anti-cancer effects and they could be promising novel therapeutic agents for chemotherapy.

Keywords: 2(3H)-benzoxazolone; MCF-7; apoptosis; breast cancer; cytotoxicity; mannich reaction.