LAUSR

Background: Renal cell carcinoma (RCC) is a common cancer of the urinary system. Chinese medicine is being extensively used in the treatment of various cancers. Recent studies found that Poria cocos, a widely used Chinese medicine, has an anti-tumor effect. Pachymic acid (PA) is a triterpenoid compound of P. cocos, and the present study investigated whether PA is a main anti-tumor active ingredient of this fungus. Methods: The effects of PA on cell viability, proliferation, adhesion, invasion, and metastasis were assessed by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazole bromide, colony formation, cell adhesion, wound healing, and Transwell assays. High-content imaging was used to dynamically observe and verify the inhibitory effect of PA on cell motility, and Western blot was used to detect the expression of matrix metalloproteinase-related proteins and epithelial–mesenchymal transformation proteins. Result: The in vitro assays demonstrated that PA was able to reduce the viability, proliferation, adhesion number, wound healing rate, and transmembrane number of the RCC cells. In addition, high-intensive imaging indicated that PA shortened the traveling distance and slowed the movement of the RCC cells. Western blots showed that in the PA-treated RCC cells, E-cadherin expression was increased, whereas N-cadherin and Vimentin expression was decreased. Furthermore, the expression levels of matrix metalloproteinase-2, matrix metalloproteinase-9, and tissue inhibitor of metalloproteinase-1 were all decreased by the PA administration. Conclusion: PA inhibited the invasion and metastasis of RCC, and these results suggest that PA may be an effective anti-tumor component of P. cocus.