OBJECTIVE: To probe into the mechanism of "dandelion-selfheal"in treatment of breast cancer based on network pharmacology. METHODS: To screen the main chemical component and target spot of the herbal pair of "dandelion-selfheal"through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform（ TCMSP）

so as to establish the protein-protein interaction（ PPI） network of "component-target". Comparative toxicogenomics database（ CTD） was used to retrieve genes related to breast cancer

Cytoscape 3. 6. 1 was adopted to construct "disease-target " PPI network. Based on the Merge function of Cytoscape 3. 6. 1

the PPI networks of "component-target"and "disease-target"were merged to screen out the main core network. With the help of the David database

Reactome database and Omicshare platform

gene ontology（ GO） enrichment analysis and Kyoto encyclopedia of genes and genomes（ KEGG） pathway enrichment analysis were conducted. Through animal experiments

the anti-tumor mechanism of the herbal pair of "dandelion-selfheal"was verified. RESULTS: A PPI network of "component-target"containing 383 nodes and 594 linked herbal pair of "dandelion-selfheal"and a PPI network of "disease-target"of breast cancer containing 500 target spots were screened out. With utilization of the network merger

a "component-target-disease"network containing 61 core targets was finally established. The result of gene GO function analysis was mainly related to biological process and molecular function; the result of gene KEGG pathway enrichment analysis was related to immune system

sex hormone secretion

proliferation and apoptosis of tumor cell. The result of animal experiment showed that the herbal pair of "dandelion-selfheal"can increase the IL-6 level

inhibit the proliferation of breast cancer cells and promote the apoptosis of breast cancer cells in model mice.CONCLUSIONS: The possible mechanism of herbal pair of"dandelion-selfheal"in treatment of breast cancer is related to immune system regulation

sex hormone secretion

tumor cell proliferation and apoptosis.