Figure 1.

The cytotoxic effect and necroptosis induction of GTN on MDA-MB-231 cells. The cell viability of goniothalamin (GTN) in the presence or absence of z-VAD-fmk against human breast cancer MDA-MB-231 cells and MCF-10A cells were determined by the MTT ((3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay (A). Percent of propidium iodide-positive cells in the condition with or without z-VAD-fmk at a GTN concentration of IC₀, IC₂₀, and IC₅₀ were measured by annexin V-fluorescein isothiocyanate and PI staining followed by FACs (B). Transmission electron micrograph of the untreated MDA-MB-231 cell (C) compared to GTN co-treated with z-VAD-fmk (D), 0.03% hydrogen peroxide-treated cell as a positive control (E), z-VAD-fmk-treated cell (F) and GTN-treated cell (G) (N = nucleus, green arrowhead = intact membrane, red arrowhead = collapsed membrane and blue arrowhead = blebbing membrane). The results were collected from three independent experiments in triplicate, the significance of statistical values compared to the control (without treatment) are marked with * p < 0.05; ** p < 0.01, and compared to GTN alone are marked with # p < 0.05; ## p < 0.01.