There’s new evidence that an enzyme found in pineapples may make peritoneal mesothelioma cells more susceptible to the toxic effects of chemotherapy.
Mesothelioma is an aggressive malignancy with a poor prognosis, largely due to the fact that standard treatments, including chemotherapy, are not usually very effective. The pineapple-derived enzyme bromelain has been shown in previous studies to have a negative impact on breast and pancreatic cancer cells. Now, Australian researchers have found that it may also be toxic to peritoneal mesothelioma cells, especially when used along with the drug cisplatin.
Bromelain works against cancer by breaking down a protein called MUC-1. Found in several different mesothelioma cell lines, MUC-1 helps cancer cells invade, spread and withstand the toxic effects of chemotherapy. When researchers at the University of New South Wales tested different concentrations of bromelain with and without the chemotherapy drugs cisplatin and 5-FU on mesothelioma cells, they produced some promising results.
The treated mesothelioma cells were assessed after 4 and 72 hours. The viability of both cell lines was adversely affected by the bromelain alone. In combination with a chemotherapy drug, the effects were even more dramatic. “The addition of bromelain increased the cytotoxicity of cisplatin significantly in both cells lines,” the team reports in the journal Anticancer Drugs. Bromelain did not appear to increase the cytotoxicity of 5-FU.
The authors further report that bromelain-induced mesothelioma cell death is by apoptosis, or programmed cell death, and through autophagy, the natural breakdown of cells into their component parts. Based on the results of this and another bromelain/mesothelioma study earlier this year, the authors conclude, “Bromelain has the potential of being developed as a therapeutic agent in malignant peritoneal mesothelioma.”
As with all potential new treatments, bromelain will have to undergo more testing to determine its safety and effectiveness in human mesothelioma patients. Human trials of bromelain will also help to establish the best dosing strategy. Although bromelain is sold as a dietary supplement, there is no evidence that taking the supplement could enhance mesothelioma treatment. Mesothelioma patients should always discuss supplementation with their physician.
Pillai, K, et al, “Anticancer effect of bromelain with and without cisplatin or 5-FU on malignant peritoneal mesothelioma cells”, February 25, 2014, pp. 150-160.