A Network Pharmacology Approach for Uncovering the Antitumor Effects and Potential Mechanisms of the Sijunzi Decoction for the Treatment of Gastric Cancer.

Background: Sijunzi decoction (SJZD), a classic Chinese formula, has been clinically used for the treatment of gastrointestinal disorders. However, few studies have uncovered its antitumor effects and its potential mechanisms against gastric cancer (GC). Therefore, this work aimed to identify the active compounds and putative targets of the SJZD and to further explore the potential mechanisms involved in the treatment of GC. Materials and Methods: The active compounds and potential targets of the SJZD and related genes for GC treatment were collected from a public database. Traditional Chinese medicine (TCM)-compound-target-disease networks, Venn diagrams, protein-protein interactions (PPIs), gene ontology (GO), and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to obtain the bioactive compounds, key targets, and potential pathways. Next, the human gastric adenocarcinoma cell line NUGC-4 was inoculated subcutaneously into the right flank of NCG mice to build a tumor-bearing mouse model to further verify the findings. Results: There were 117 compounds in the SJZD in total. The SJZD and GC had 161 and 3288 potential targets, respectively, among which 123 targets overlapped. The network analysis showed that quercetin, kaempferol formononetin, ginsenoside, atractylenolide III, etc., were bioactive molecules. The tumor necrosis factor (TNF), interleukin-6 (IL-6), cellular tumor antigen p53 (TP53), transcription factor AP-1 (JUN), and vascular endothelial growth factor A (VEGFA) were potential targets. A KEGG pathway enrichment analysis revealed 110 pathways involved in the pathways for cancer, including the PI3K-AKT signaling pathway. Validation experiments showed that the SJZD inhibited tumor growth and induced apoptosis in tumor cells. In addition, the SJZD downregulated expressions of VEGFA, iNOS, COX-2, and Bax/Bcl2 and inhibited the expressions of p-PI3K and p-AKT. Conclusion: The SJZD treats GC by inhibiting blood vessel hyperplasia and inducing cell apoptosis by regulating the PI3K/AKT pathway.