HDAC1 and adenocarcinoma: Furthermore, melatonin treatment significantly upregulated the expression of Bcl-2 associated X protein (Bax), p53 upregulated modulator of apoptosis (PUMA) and ROS, enhanced the caspase 3 activity, and downregulated the B-cell lymphoma-2 (Bcl-2) and GSH levels via the inhibition of histone deacetylase-1 (HDAC1) signaling pathway in adenocarcinoma cells [14] (Figure 3A).