Our previous work (Zhang et al., 2017) demonstrated that treatment simultaneously with HDAC inhibitor TSA (T), DNMT inhibitor AZA (A), LSD1 inhibitor SP2508 (L), and EZH2 inhibitor EPZ-6438 (E) led to post-mitotic neuron-like differentiation, whereas treatment with an individual inhibitor usually resulted in weaker or no significant changes in cancer cells, suggesting that these epigenetic modification enzymes may work cooperatively to regulate the neuron-like differentiation effect in cancer cells. The gene discussed is HDAC9; the disease is cancer.