Cancer stem cells (CSCs), also known as cancer-causing cells, are a hot topic among researchers. These cells are resistant to current treatments and play a significant role in both metastasis and recurrence, which are two of the biggest challenges in cancer treatment. For this reason, it is of great interest to find effective ways to clarify CSCs. Researchers at the University of Salford in the United Kingdom may have discovered treatment that could play an important role. These scientists take their time to test drugs that the Food and Drug Administration (FDA) has already approved. They examine whether any existing drugs might be able to help in the fight against cancer. Focusing on drugs in this way means that you find an existing drug that works against cancer, could potentially reach the clinic faster. In a recent article now published in the journal Frontiers in Oncology, scientists outline the potential use of an antibiotic called doxycycline rid out CSCs. Usually, specialists prescribe doxycycline – which is one of the most common global antibiotics – to treat conditions such as pneumonia, chlamydia, sinusitis, syphilis, cholera and Lyme disease.
Doxycycline works by preventing cells from creating new mitochondria, which are cell power plants. It is important to stress that the drug has minimal side effects. For the current study, the researchers recruited only 15 participants at the University Hospital of Pisa, Italy. They gave nine participants doxycycline every day for 14 days before surgery to remove a tumor. The remaining six participants acted as controls and did not take drugs. To assess whether the antibiotic had an impact on CSCs and the possibility of cancer recurrence, scientists tested a number of markers. They evaluated these so-called stem cells in the tumor tissue removed prior to surgery (core biopsies) and tumor tissue removed during the procedure. Scientists measured a significant decline in CSCs in almost all the participants taking doxycycline. Although the numbers of the participants were very low, the results were very significant, which means that a clinical trial would be worthwhile. Mitochondria have evolved from bacteria and antibiotics attack bacteria; this means that antibiotics often also target mitochondria, which prevent the reproduction of stem cells.
These findings could have significant consequences, as explained by the joint researcher Prof. Michael Lisanti: “What we deduce here is that stem cells selectively overexpress key mitochondrial proteins, which means that if we are able to inhibit mitochondrial function, stem cells can be knocked out. We have very few FDA approved drugs to target and reduce cancer stem cells, so find that a drug that is effective, easily available and costs only 20 cents per patient per day is very significant, in particular because about two-thirds of cancer deaths occur following a relapse after the first chemotherapy. In recent years, more and more researchers have focused on mitochondria as a potential pathway for treating diseases: Probably this information will feed the flame, for their usefulness against other conditions The ability to treat cancer can only be improved by using drugs that are not only cheap but also widely available. These drugs can go directly to Phase II clinical trials, saving considerable amounts of time (10-15 years) and billions of financials. Doxycycline became clinically available in 1967; unbelievable but true, its antitumor activity has been right under our nose for more than 50 years”.
- edited by Dr. Gianfrancesco Cormaci, PhD, specialist in Clinical Biochemistry.
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