Discovery of the antitumor activities of a potent DCN1 inhibitor compound 383 targeting LSD1 in gastric cancer.

Dual target compounds have become a hot spot in the treatment of cancer in recent years. Histone lysine specific demethylase 1 (LSD1) is identified as histone demethylase and acts as a key regulator involved in many other cellular activities through its demethylation function. We have reported a triazolo [1,5-α] pyrimidine-based DCN1(defective in cullin neddylation protein 1) inhibitor compound 383 (IC50 = 11 nM) which could selectively inhibit Cullin 3/1 neddylation in MGC-803 cells. In this research, we investigated that compound 383 could target LSD1 and inhibit the biological function of LSD1 in MGC-803 cells (IC50 = 0.53 µM). We found that compound 383 could induce the degradation of LSD1 and inhibit MGC-803 cell proliferation, migration and invasion in a dose-dependent manner. Compound 383 could cause cell cycle arrest at G2/M phase by down-regulating the expression of LSD1. In addition, compound 383 could significantly reverse epithelial-mesenchymal transition (EMT) through increase H3K4me methylation at E-cadherin promotor. Furthermore, the in vivo inhibitory effect of compound 383 without obvious toxicity was confirmed in nude mouse transplanted MGC-803 tumor cells model. Collectively, these results suggest that the DCN1 inhibitor compound 383 exhibits antiproliferative activity in gastric cancer cells by targeting LSD1 which promotes compound 383 as a good starting point for the development of dual-target therapeutics for gastric cancer.