A popular antidepressant has been found to slow down the growth of cancer cells, according to researchers at the university of Leuven.
The research, so far carried out only on laboratory animals, found that the drug sertraline, commonly marketed under the trade name Zoloft, had an effect on a mechanism used by cancer cells to reproduce themselves.
Cancer cells are notable for their aggressive growth, which is promoted by a variety of methods depending on the type of cancer. In some forms of breast cancer, leukaemia, skin cancer, brain tumours and lung cancer, the cells produce two amino acids, serine and glycine, which have such an effect on the cells they become virtually addicted.
“Precisely because the cancer cells are so dependent on it, this mechanism is an interesting target,” said Professor Kim De Keersmaecker, head of the university’s Laboratory for Disease Mechanisms in Cancer (LDMC).
“Healthy cells use this mechanism to a lesser extent and also absorb serine and glycine from food. This is not enough for the cancer cells, causing them to produce more. If we can stop this production, we can fight the cancer without affecting healthy cells.”
The researchers went looking in a database of medications, looking for something that affects the creation of serine and glycine, later testing 1,600 possible candidate medications on yeast cells in the lab.
“There are yeasts, or fungi, that depend on the same mechanism,” explained research coordinator Dr. Karin Thevissen.
“Certain yeasts produce these amino acids to protect themselves against antifungals. In addition, you can easily cultivate yeast cells, so that you can test many different substances.”
The most effective drug found turned out to be sertraline, a drug in the SSRI class of antidepressants used to treat not only depression but also obsessive-compulsive disorder, post-traumatic stress and panic attacks.
The anti-cancer effects of sertraline had previously been noted in other research, but the exact mechanism remained a mystery.
“This study has allowed us to show that sertraline inhibits the manufacture of serine and glycine, so that the cancer cells stop growing,” the researchers said. And they recommended using the drug in combination with other therapeutic methods.
“Now that we have been able to describe this mechanism for breast cancer, we can investigate other types of cancer that also depend on serine and glycine synthesis,” said Prof. De Keersmaecker.
“This is the case with T-cell leukaemia, as well as certain types of brain, lung and skin cancer. The more tumours we can identify that are sensitive to sertraline, the better the prospects are for helping patients in the future.”