Melatonin Inhibits Reactive Oxygen Species-Driven Proliferation, Epithelial-Mesenchymal Transition, and Vasculogenic Mimicry in Oral Cancer

Figure 2

Melatonin inhibited the proliferation and enhanced the apoptosis of oral cancer cells via inactivation of ROS-dependent Akt pathway. (a–f) Cal27 and FaDu cells were exposed to melatonin (1 mM), NAC (5 mM), or the vehicle (control) for 24 h. (a) MTT assay was performed to measure the viability of Cal27 and FaDu cells. (b) Colony formation assay was conducted to determine the proliferation of Cal27 and FaDu cells. (c) The colony numbers were calculated. (d) Flow cytometry was carried out to analyze the apoptosis of Cal27 and FaDu cells. (e) The percentage of apoptotic cells was calculated. (f) Cell apoptosis was evaluated by enrichment factor assay. (g) Cal27 and FaDu cells were treated with melatonin (1 mM) or vehicle (control) for 24 h. Western blot was performed to detect the expressions of p-Akt, Akt, cyclin D1, PCNA, Bcl-2, and Bax. GAPDH was used as endogenous control. (h) Cal27 and FaDu cells were treated with LY294002 (20 μM), NAC (5 mM), or the vehicle (control) for 24 h. Representative Western blot results of p-Akt, Akt, cyclin D1, PCNA, Bcl-2, and Bax. GAPDH was used as endogenous control. The ratios from the indicated proteins to GAPDH are indicated below the bands. Data are represented as the mean ± SD of three independent experiments. versus control group. Ctrl: control; Mel: melatonin; NAC: N-acetyl-L-cysteine. versus control group.

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