Hospital superbug MRSA could be wiped out by breast cancer drug Tamoxifen

A team of researchers at the University of California-San Diego School of Medicine and the Skaggs School of Pharmacy and Pharmaceutical Sciences have recently determined that the breast cancer drug tamoxifen can actually boost white cell count; at least in mice.

Tamoxifen, which stops oestrogen producing cancer cells, also boosts white cells, helping them deal with the antibiotic-resistant bug.

MRSA infections affect different parts of the body, including the skin and lungs. Findings revealed that treated neutrophils were better at moving toward and engulfing bacteria and also spew out to ensnare and kill pathogens. With this approach, the researchers were able to discover the other uses of Tamoxifen.

The drug also targets the estrogen receptor, making it particularly effective against breast cancers that display the molecule abundantly. Besides being able to block the actions of the female hormone estrogen, it can also help reduce the development of breast cancer in women who are highly at risk. Treating mice with the breast cancer drug also led to enhanced clearance of MRSA and reduced death.

This means the cancer either grows more slowly or stops growing altogether. These fatty molecules are known as sphingolipids and they are independent of the estrogen receptor. Sphingolipids, and specifically one in particular, ceramide, play a vital role in governing the activities of white blood cells known as neutrophils.

However, a side-effect of Tamoxifen is enhances an excessive production of neutrophil extracellular traps.

Salvasen goes on to say, “There is no way of inducing NET formation that we know of at the moment that would not induce horrendous consequences for the host”, noting too, “These neutrophils can eviscerate their nucleus, and yet they can still move toward the (enemy)”. Past studies have shown tamoxifen’s protective effects against hepatitis C and herpes, as well as the fungus that causes yeast infections.

UC San Diego study team used Tamoxifen to shield the mice that were injected with doses of MRSA.MRSA is lethal. Repeating the experiment, scientists found that eight hours after MRSA infection, mice who had been treated with tamoxifen had a bacterial count that was 100 times lower than the control group.

Tamoxifen significantly protected mice – none of the control mice survived longer than one day after infection, while about 35 percent of the tamoxifen-treated mice survived five days. Around five times fewer MRSA were composed from the peritoneal fluid of the tamoxifen-treated mice, as compared to control mice.