Exploring the mechanism of Poria cocos against breast cancer based on UPLC-Q-TOF-MS/MS and network pharmacology
Breast cancer (BC) has surpassed lung cancer as the main cause of global cancer incidence rate, accounting for 11.7% of all cancer cases, and is the fifth leading cause of global cancer death. At present, common treatment methods such as chemotherapy, surgery, and radiation have strong adverse reactions, such as toxic side effects on the liver and kidneys of the human body, and disruption of intestinal system homeostasis. This greatly limits the effect of breast cancer treatment, so it is important to find low toxicity and high efficiency anti-tumor drugs. Most traditional Chinese medicines and their formulas have the advantages of low toxicity and high efficiency. Reasonable use is conducive to reducing the toxic side effects of cancer patients and alleviating their pain.

Poria cocos (Schw. Modern research suggests that Poria cocos has anti-tumor effect, and its extract has obvious inhibitory effect on proliferation of human liver cancer, lung cancer, breast cancer, and cervical cancer. This shows that Poria cocos has great potential to develop into an anti-tumor drug. However, the molecular mechanism and action target of Poria cocos against breast cancer are still not clear at this stage. Therefore, based on UPLC-Q-TOF-MS/MS, this paper discusses the relationship between Poria cocos and breast cancer through network pharmacology methods, and carries out preliminary verification with cell experiments to lay the foundation for further experimental research.

 

The network analysis and screening of “drug composition target disease” showed that pachymarac acid A, thumomic acid, 3-keto-linostero-7,9 (11), 24-triene-21-acid had a high degree of connectivity with related targets, which may play a potential active role in the treatment of breast cancer with pachymarac. The research shows that the components represented by tetracyclic triterpenes have significant anti-tumor activity. At present, the main components of tetracyclic triterpenes, such as pachymacic acid, are the main research objects in the published literature. The active components of anti breast cancer screened out in this study, pachymacic acid A, fumaric acid, 3-ketol-lanoste-7,9 (11), 24-triene-21-acid, which are similar in structure to pachymacic acid, are all lanostane type tetracyclic triterpenes, and have certain research value.

In this study, 301 action targets of the active ingredients of Poria cocos were obtained, and 30 common action targets were obtained by intersection with the differential genes of breast cancer. The anti breast cancer core binding proteins (PPARG, PPARA) of the active ingredients of Poria cocos were screened out. These two targets are closely related to tumors. The enrichment analysis of KEGG pathway showed that the signal pathways mainly involved in the target of breast cancer were neuroactive ligand receptor interaction, calcium signaling pathway, PPAR signaling pathway, etc. The most noteworthy one is the PPAR signaling pathway, which is consistent with our predicted core target results. PPAR is a nuclear hormone receptor activated by fatty acids and their derivatives, with three subtypes. PPARG is one of the subtypes, and its receptor agonist has been proposed as a preventive drug for breast cancer. The PPARG pathway has been clearly associated with various malignant features of human tumors, such as proliferation, invasion, distant metastasis, and involves multiple mechanisms. Some studies have shown that in the mechanism of hesperidin inhibiting breast cancer stem cells, PPARG is an important potential target and plays an important role in cell proliferation and metabolism. Under sufficient oxygen conditions, tumor cells will preferentially produce ATP and a large amount of lactate through glycolysis, providing energy for the proliferation and metastasis of tumor cells. Examining ATP content and lactate production can reflect the effect of Poria cocos on energy metabolism in tumor cells. Therefore, this experiment focused on PPARG to carry out relevant research. The cell function experiment used CCK8, scratch test and kit method to verify the effect of Poria cocos on the proliferation, metastasis and metabolic capacity of breast cancer cells. The results showed that compared with the control group, Poria cocos extract (160 ～ 640 μ g/mL) could significantly inhibit the proliferation of breast cancer cells (P<0.01); The scratch test results showed that cell migration was significantly inhibited (P<0.01); Compared with the control group, different concentrations of Poria cocos extract resulted in a decrease in lactate content in cells, while ATP levels were not significantly affected. Poria cocos extract may mainly affect other metabolic processes and thus affect cell metabolism; The results of cellular immunofluorescence showed that PPARG protein was mainly distributed in the nucleus, and the fluorescence intensity was significantly enhanced after stimulation with Poria cocos extract.

To sum up, this study revealed the targets and potential mechanisms of the active ingredients of Poria cocos based on network pharmacology analysis, further verified the affinity relationship between the active ingredients and target proteins by molecular docking technology, and experimentally verified the related effects of core targets. The results showed that Poria cocos may play an anti breast cancer role by up regulating the expression of PPARG, inhibiting the proliferation and migration of tumor cells, and affecting cell metabolism. The research results and relevant reports in the existing literature corroborate each other. The study guided the discovery of modern drugs through data, providing new insights into the material basis and mechanism of efficacy of Poria cocos in preventing and treating breast cancer.