Identification and validation of lung adenocarcinoma (LUAD)-associated targets for monascin from the extracts of Monascus purpureus-fermented rice: Compound preparation, high-throughput genome sequencing and bioinformatics analysis

Despite the remarkable bioactivities exhibited by monascin against several tumors, its therapeutic targets remain unexplored. In this study, our objective is to identify therapeutic targets based on the antitumor activity of monascin against lung adenocarcinoma (LUAD) A549 cells. The compound monascin was derived from extracts of Monascus purpureus -fermented rice. Its chemical structure was determined using spectroscopic methods, while the physicochemical properties of monascin were investigated through thermal behavior analysis. Herein, antitumor studies indicated that monascin significantly inhibited the viability of A549 cells, with an IC 50 value of 2.05 μM; RNA-sequencing revealed 12 up-regulated and 29 down-regulated genes as differentially expressed genes (DEGs) for A549 cells in response to monascin; RT-qPCR validation supported the plausibility of the RNA-sequencing results. Moreover, utilizing data from the Cancer Genome Atlas (TCGA) database, univariate and multivariate Cox regression analyses provided evidence supporting GPR37 and FAM83A as potential candidate genes for predicting disease progression in LUAD patients. Additionally, the LASSO Cox regression and nomogram analyses confirmed that FAM83A and GPR37 genes had the potential to predict overall survival for LUAD patients. Finally, molecular docking studies suggested that monascin could interact with both GPR37 and FAM83A proteins through the hydrogen bonding and hydrophobic interactions; Western blotting assays indicated that monascin inhibited the expression levels of both GPR37 and FAM83A proteins. Overall, the clinical prognosis of GPR37 and FAM83A highlights the rationale for targeting these specific genes with monascin. Additionally, there findings provide compelling evidence for the ploypharmacological properties of monascin against LUAD.