A study has reported that piperine, a bioactive component of black pepper, can increase breast cancer cell death and reduce resistance to Adriamycin (doxorubicin) in breast cancer cells. The study was designed to investigate the activity of piperine in chemotherapy-resistant cancer cells. P-gp, MRP1 and BCRP are ABC transporters, which serve to assist in moving various compounds across cellular membranes. ABC transporters can help expel a variety of anti-cancer drugs, thereby protecting tumor cells. Over-expression of P-gp, MRP1 and BCRP in tumor cells is an important mechanism leading to multidrug resistance, which reduces the effectiveness of chemotherapy immediately in a few patients or over time in most others. The authors identified piperine as a multidrug resistance inhibitor during a screening of potential multidrug resistance reversal agents.

Piperine was found to increase the cytotoxicity of anti-cancer drugs in drug resistant sublines, including MCF-7/DOX and A-549/DDP. MCF-7/DOX cells are MCF-7 breast cancer cells with high resistance to Adriamycin and other chemotherapy drugs and A-549/DDP are multidrug-resistant human lung cancer cells. Piperine was found to reverse resistance to Adriamycin 32.16-fold in the resistant breast cancer cells and 14.14-fold in the resistant lung cancer cells. Piperine also re-sensitized cells to mitoxantrone (which is used to treat leukemia and prostate cancer) 6.98-fold. Furthermore, long-term treatment of cells by piperine was found to inhibit transcription of the corresponding ABC transporter genes, thereby reducing the cellular levels of the ABC transporters. The authors conclude that piperine appears capable of reversing multidrug resistance by several mechanisms and it may be a promising compound for future studies.

Please see our article breast cancer diet during Adriamycin chemotherapy for more information.