Network Pharmacology-based Prediction and Verification of Shikonin for Treating Colorectal Cancer

Shikonin (SKN), a naturally occurring naphthoquinone, is a major active chemical component isolated from Lithospermum erythrorhizon Sieb Zucc, Arnebia euchroma (Royle) Johnst, or Arnebia guttata Bunge, and commonly used to treat viral infection, inflammation, and cancer. However, its underlying mechanism has not been elucidated.

This study aims to explore the antitumor mechanism of SKN in colorectal cancer (CRC) through network pharmacology and cell experiments.

SymMap database and Genecards were used to predict the potential targets of SKN and CRC, while the cotargets were obtained by Venn diagram. The cotargets were imported into the website of String and DAVID, constructing the protein-protein interaction (PPI) network, performing Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, the Compound-Target-Pathway (C-T-P) network was generated by connecting potential pathways with the corresponding targets.

According to the results of network pharmacological analysis, the cell experiments were used to verify the key signal pathway. The most relevant target of SKN for the treatment of CRC was PI3K/Akt signaling pathway. SKN inhibited CRC cells (HT29 and HCT116) proliferation, migration, and invasion, and promoted cell apoptosis by targeting IL6 and inhibiting the IL6R/PI3K/Akt signaling pathway. SKN promotes apoptosis and suppresses CRC cells' (HT29 and HCT116) activity through the PI3K-Akt signaling pathway.

This research not only provided a theoretical and experimental basis for more in- -depth studies but also offered an efficient method for the rational utilization of a series of Traditional Chinese medicines as anti-CRC drugs.