DHA/EPA-Enriched Phosphatidylcholine Suppresses Tumor Growth and Metastasis via Activating Peroxisome Proliferator-Activated Receptor γ in Lewis Lung Cancer Mice

In the present study, the antitumor effects of docosahexaenoic acid-phosphatidylcholine (DHA-PC) and eicosapentanoic acid-phosphatidylcholine (EPA-PC) in Lewis lung cancer mice were investigated. As observed, DHA-PC and EPA-PC obviously inhibited the transplanted tumor growth and the positive expression of Ki67. The metastatic nodules and hematoxylin and eosin (HE) staining of the lung indicated that DHA-PC and EPA-PC suppressed lung metastasis. PPARγ has a key role in cell survival, which may be a target for cancer therapy. Further mechanism research indicated that DHA-PC and EPA-PC significantly enhanced the levels of PPARγ and subsequently downregulated the NF-κB pathway. DHA-PC and EPA-PC accelerate cancer cell apoptosis by decreasing NF-κB-mediated antiapoptotic factors Bcl-2 and Bcl-XL, thereby inhibiting tumor growth. In addition, DHA-PC and EPA-PC significantly decreased the levels of NF-κB-mediated matrix metallopeptidase 9 (MMP9) and heparanase (HPA), which block the extracellular matrix (ECM) degradation, thereby suppressing lung metastasis. These findings suggested that DHA-PC and EPA-PC could be used as food supplements and/or functional ingredients for cancer patients.