Fig. 8.

Inhibition of autophagy by 3-MA triggers melatonin-induced activation of apoptotic proteins in glioblastoma cells. The protein expression levels of Beclin 1, LC-3, Bcl-2 and Bax were assessed in U87MG (a, b) and A172 (c, d) cells by Western blotting. The cells were treated with DMSO as a negative control, 3-MA (10 mM), or melatonin (1 mM) or were co-treated with 3-MA and melatonin for 24 h. The 3-MA was added to the cell culture medium 1 h prior to the administration of melatonin. The protein bands for each treatment regimen were quantified by densitometry, and their differences are presented in the graph. The values represent the mean ± S.E.M. for three separate determinations. Statistical significance *P < 0.05 and **P < 0.01 compared with the corresponding groups