Actinoquinazolinone, a New Quinazolinone Derivative from a Marine Bacterium Streptomyces sp. CNQ-617, Suppresses the Motility of Gastric Cancer Cells.

A HPLC-UV guided fractionation of the culture broth of Streptomyces sp. CNQ-617 has led to the isolation of a new quinazolinone derivative, actinoquinazolinone ( 1 ), as well as two known compounds, 7-hydroxy-6-methoxy-3,4-dihydroquinazolin-4-one ( 2 ) and 7-methoxy-8-hydroxy cycloanthranilylproline ( 3 ). The interpretation of 1D, 2D NMR, and MS spectroscopic data revealed the planar structure of 1 . Furthermore, compound 1 suppressed invasion ability by inhibiting epithelial-mesenchymal transition markers (EMT) in AGS cells at a concentration of 5 µM. In addition, compound 1 decreased the expression of seventeen genes related to human cell motility and slightly suppressed the signal transducer and activator of the transcription 3 (STAT3) signal pathway in AGS cells. Together, these results demonstrate that 1 is a potent inhibitor of gastric cancer cells.