Investigating the molecular mechanism of Mori Cortex against osteosarcoma by bioinformatics analysis and in vitro experimental

Abstract

Objective: To explore the therapeutic mechanism of Mori Cortex against osteosarcoma (OS), we conducted bioinformatics prediction followed by in vitro experimental validation.

Methods: Gene expression data from normal and OS tissues were obtained from the GEO database and underwent differential analysis. Active Mori Cortex components and target genes were extracted from the Traditional Chinese Medicine System Pharmacology database. By intersecting these targets with differentially expressed genes in OS, we identified potential drug action targets. Using the STRING database, a protein-protein interaction network was constructed. Subsequent analyses of these intersected genes, including Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway enrichment, were performed using R software to elucidate biological processes, molecular functions, and cellular components, resulting in the simulation of signaling pathways. Molecular docking assessed the binding capacity of small molecules to signaling pathway targets. In vitro validations were conducted on U-2 OS cells. The CCK8 assay was used to determine drug-induced cytotoxicity in OS cells, and Western Blotting was employed to validate the expression of AKT, extracellular signal-regulated kinases (ERK), Survivin, and Cyclin D1 proteins.

Results: Through differential gene expression analysis between normal and OS tissues, we identified 12,364 differentially expressed genes. From the TCSMP database, 39 active components and 185 therapeutic targets related to OS were derived. The protein-protein interaction network indicated that AKT1, IL-6, JUN, VEGFA, and CASP3 might be central targets of Mori Cortex for OS. Molecular docking revealed that the active compound Morusin in Mori Cortex exhibits strong binding affinity to AKT and ERK. The CCK8 assay showed that Morusin significantly inhibits the viability of U-2 OS cells. Western Blot demonstrated a reduction in the p-AKT/AKT ratio, the p-ERK/ERK ratio, Survivin, and Cyclin D1.

Conclusion: Mori Cortex may exert its therapeutic effects on OS through multiple cellular signaling pathways. Morusin, the active component of Mori Cortex, can inhibit cell cycle regulation and promote cell death in OS cells by targeting AKT/ERK pathway.