Cancer is a leading cause of death worldwide and its incidence and mortality are rising, mainly in developed countries.
The fight against cancer has become more challenging with the rise of multidrug resistant cancers – those that have developed a defence mechanism to stop chemotherapy drugs from working. In a paper published in Bioorganic & Medicinal Chemistry Letters, it was shown how some newly discovered molecules called selenocompounds can block cancer cells’ defenses against treatment, making drugs more effective.
Researchers at the University of Navarra, Spain and Saarland University, Germany worked to synthesize selenium-containing compounds. Selenium is essential for the body’s cells and is found in many multivitamins. Selenium deficiency can cause the bone disorder Kashin-Beck disease and the heart disorder Keshan disease. Research has also shown that taking selenium supplements can reduce the risk of some cancers.
Their selenocompounds showed strong activity against cancer cells in the lab: they limited the growth of cancer cells, in some cases killing them, and stopped cancer from developing. Through a literature search a study was found that showed similar selenocompounds enhance the potency of chemotherapy drugs used in cancer treatment, so they investigated more in-depth.
When exposed to aggressive chemotherapy drugs, some cancer cells can develop defence mechanisms – one such mechanism is a protein in the cell membrane that acts like a pump and pushes the drug back out of the cell. These proteins are called efflux pumps, and one common pump is ABCB1.
Experiments showed that the selenocompounds attached to the ABCB1 efflux pumps, blocking them. They also found that the selenocompounds were able to trigger the process of cell suicide, called apoptosis, in cancer cells. The most active was just as potent as a known apoptotic compound, killing 80 percent of the cells.
The ultimate aim of cancer research is to give more chances to people whose lives are at risk due to this disease. The development of pharmaceutical drugs requires a lot of effort and time, and the results of their study are just preliminary.
They hope that in the future, their work will serve as the basis to develop new drugs against cancer that reach the patients who need them.