Breast Tumour drug could wipe out SUPERBUG

A common breast cancer drug could wipe out an antibiotic-resistant notorious superbug responsible for several difficult-to-treat infections in different parts of the body, according to a new research.

The study’s author Professor Victor Nizet said: “The threat of multidrug-resistant bacteria is growing, yet the pipeline of new antibiotics is drying up. The “off-target effects” we identified in this study could have critical clinical implications given the large number of patients who take tamoxifen, often every day for years”.

“We need to open the medicine cabinet and take a closer look at the potential infection-fighting properties of other drugs that we already know are safe for patients”, Nizet said.

With the means of this approach, researchers were able to discover that tamoxifen has pharmacological properties that is capable of helping the immune system in cases where a patient is immuno-compromised or where outdated antibiotics have otherwise failed.

The researchers warned that the effectiveness of tamoxifen against MRSA in their study may differ with other pathogens and that too many NETs could be harmful and have been linked to inflammatory disease such as bronchial asthma. Sphingolipids, and specifically one in particular, ceramide, play a vital role in governing the activities of white blood cells known as neutrophils.

To verify the theory, researchers incubated human neutrophils with the drug and compared it to untreated neutrophils. First of all, while it can be effective in fighting against MRSA, the outcome against other pathogens may vary as bacterial species evolve constantly to avoid neutrophil extracellular traps or NETs. Treating mice with the drug also led to enhanced clearance of MRSA and reduced death. So researchers at the University of California, San Diego gave tamoxifen to mice and then injected them with normally lethal levels of MRSA. Five times fewer MRSA were found in peritoneal fluid taken from the mice’s abdomens.

More than targeting estrogen receptors, tamoxifen is shown to have other favorable effects, including influencing the production of sphingolipids, which are involved in regulating white blood cells known as neutrophils.

The study is published October 13 by Nature Communications.