Dihydroartemisinin (DHA), a well-known
antimalarial drug, has been widely investigated for its antitumor effects in multiple
malignancies. However, its effects and regulatory mechanisms in
colorectal cancer (CRC) are still unproved. In this study, in vitro experiments including CCK8, EdU, Transwell, and flow cytometry analyses and an in vivo
tumorigenesis model were conducted to assess the effects of DHA on the bio-behaviors of CRC cells. Additionally,
RNA-seq combined with gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses was used to obtain the targets of DHA, and these were verified by molecular docking, qRT-PCR, and Western blotting. As a result, we found that DHA significantly suppressed the proliferation,
DNA synthesis, and invasive capabilities and induced cell apoptosis and cell cycle arrest in HCT116, DLD1, and RKO cells in vitro and in vivo. Further analyses indicated that the targets of DHA were predominantly enriched in cell cycle-associated pathways, including CDK1, CCNB1, and PLK1; and DHA could bind with the CDK1/CCNB1 complex and inhibit the activation of CDK1/CCNB1/PLK1 signaling. Moreover,
cucurbitacin E, a specific inhibitor of the CDK1/CCNB1 axis, enhanced the inhibitory effects of DHA on
DNA synthesis and colony formation in HCT116 and DLD1 cells. In short, DHA could suppress the
tumorigenesis and cycle progression of CRC cells by targeting CDK1/CCNB1/PLK1 signaling.