Study On The Inhibition Of The Metastasis Of Breast Cancer By Beta-elemene Based On Aerobic Glycolysis

Bcakground and PurposeBreast cancer is one of the malignant tumors with high incidence and mortality in females.Mortality from breast cancer is almost always due to metastatic spread to other organs.According to traditional Chinese medicine,tumor is the accumulation of stagnation of Qi and blood stasis.Modern medicine thinks that this mass in the abdomen accumulation is a kind of hyperplasia tissue,which can be developed into tumor and should be treated with the method of activating blood and removing stasis and dispersing.Blood-breaking drugs are the most powerful ones in promoting blood circulation and removing blood stasis,and are often used in the treatment of women’s diseases.Aerobic glycolysis is a unique metabolic manner of tumor cells,providing energy for tumor cell growth,metastasis,and so on.The TCM holds that tumor belongs to the typical blood stasis syndrome,and the energy metabolism of the hyperplastic tissue of the blood stasis area is similar to that of tumor,and is also carried out in the mode of aerobic glycolysis.Therefore,when eliminating blood stasis,blood-breaking drugs may also affect the energy metabolism of this place.The influence of aerobic glycolysis is the essence of blood-breaking drugs which removing blood stasis and dispersing blood stasis.P-elemene is the main anti-tumor component of Curcuma zedoaria,which can affect tumor proliferation,apoptosis,metastasis and immunity and enhance the sensitivity of radiotherapy and chemotherapy without myelosuppression and obvious liver and kidney damage.Thus,we have reason to think that β-elemene is a low toxic and effective traditional Chinese medicine candidate for reducing breast cancer metastasis.In this study,we verified the inhibitory effect ofβ-elemene on breast cancer metastasis,based on the relationship between energy metabolism and metastasis,we further investigated the influence of β-elemene on aerobic glycolysis in breast cancer cells with different metastatic ability to clarify its mechanism.In view of this,a preliminary experimental basis is established for studying the common regularity of anti-metastasis of blood-breaking drugs.Research Contents and ResultsIn this study,we examined the effect of β-elemene on breast cancer metastasis by combining wound scratch,transwell,tube formation,and rat aortic ring assay and orthotopic xenograft of breast cancer.The results showed that(3-elemene could significantly inhibit the metastasis of glycolysis dependent breast cancer with high and low metastatic ability both in vitro and in vivo.Using HPLC-MS,kits of ATP,glucose,pyruvate and other metabolites,Seahorse XFe24 Extracellular Flux Analyzer,we found that P-elemene decreased ECAR,the absorption of glucose and the production of ATP,pyruvate and lactate of MDA-MB-231 and MCF-7 cells in vitro,inhibiting the process of glycolysis.Although P-elemene had no influence on the proliferation of primary tumor,it could selectively inhibit the metabolism of liver and lung metastases of nude mice with high and low metastatic breast cancer cells.We further detected the glycolysis-related kinase activity,β-elemene was found to only inhibit pyruvate kinase activity.Western,immunofluorescence,immunohistochemical staining and other experiments confinned that β-elemene inhibited breast cancer metastasis by suppressing PKM2 entering into the nucleus,which was accomplished by inhibiting expression of importin a5,affecting the expression of glucose transporter,lactate dehydrogenase,lactate transporter to influence glycolysis and the living environment and the way which tumor cells preferred.Conclusion and SignificanceThis subject connects the efficacy of resolving stasis and dissolving lump with energy metabolism from the breakthrough point of the drug component-target-pathway of blood-breaking drugs,which embodies the "cure" of traditional Chinese medicine,and seeks to explain the common mechanism of anti-tumor metastasis of blood-breaking drugs with a new angle.This research uses the effective component of Curcuma zedoaria,β-elemene,as the representative to study the anti-tumor effect of blood breaking drugs.It has laid an experimental foundation for studying the anti-tumor effect of blood-breaking drugs,and has made a key step to solve the doubts about the clinical use of blood breaking drugs in the treatment of tumors.The subject confirmed β-elemene can inhibit breast cancer metastasis dependent on catalytic and protein kinase activity of PKM2 in vivo and vitro.β-elemene decreased the activity of pyruvate kinase by regulating the conversion of dimeric/tetrameric PKM2 to inhibit the glycolytic process of breast cancer cell.By decreasing the expression of EGFR and importin a5,β-elemene inhibited the nuclear translocation of PKM2,and significantly reduced the level of GLUT1,LDHA,MCT1 and MCT4 resulted in the inhibition of the metastasis of breast cancer.