Cinobufacini induced MDA-MB-231 cell apoptosis-associated cell cycle arrest and cytoskeleton function

Cinobufacini is a traditional Chinese anti-tumor drug and widely used in clinic experiences. But little is known about its effect on the cells. In this study, the effects of cinobufacini on breast cancer MDA-MB-231 cell were evaluated by CCK-8 assay, and the data showed cinobufacini could inhibit the MDA-MB-231 cells growth effectively in dose-dependent and time-dependent manners. Cell apoptosis and cell cycle were detected by flow cytometry analysis. After the cells being treated with 50 μg/mL cinobufacini for 48 h, the early apoptosis percentage (20.45 ± 1.46%) is much higher than the normal group (7.73 ± 1.21%). The cell cycle data indicated that cinobufacini caused a cell cycle arrest at S phase. What’s more, cinobufacini can affect the disruption of cytoskeleton, and these alterations changed the cell-surface ultrastructure and the cell morphology which were detected by atomic force microscopy (AFM) at nanoscale level. It indicated that the cell membrane structure and cytoskeleton networks were destroyed and the cell tails were narrowed after the cell being treated with cinobufacini. The present study is to provide valuable new insights to understand the mechanism of the drug in anti-tumor process. Furthermore, the knowledge concerning the signaling of cell cycle is potentially important to clinical utility.

Cinobufacini could induce MDA-MB-231 cell apoptosis, AFM images showed that cinobufacini could changes the cell surface significantly (Fig. 2). LCSM images showed the cells before being treated with cinobufacini, the cells were spindle, a large number of F-actin around the nucleus regularly in the cells and the fibers in the cytoplasm arranged as regular rays. The cells after being treated with cinobufacini (50 μg/mL) for 48 h, F-actin dispersed in the cells and stress fibers around the nucleus arranged in disorder and the numbers were decreased, the nuclei deformed, there were some holes in the middle of the nuclei (Fig. 4) and cinobufacini caused a cell cycle arrest at S phase.Figure optionsDownload as PowerPoint slide