Scientists have found a way to deprive cancer cells of nutrition without harming healthy cells

Conventional cancer treatments often harm not only the tumor, but also the body as a whole, causing severe side effects. Therefore, researchers are looking for methods that act as precisely as possible. The international team proposed a non-standard solution: to use the D-form of cysteine, a molecule that differs from the usual L-form only in its spatial configuration.

It turns out that this sulfur-containing amino acid is preferentially taken up by certain types of cancer cells and disrupts their key processes, including cellular respiration and DNA synthesis. At the same time, healthy cells remain practically insensitive to its effects.

Amino acids exist in two “mirror” versions – L and D. Although they are the same in chemical composition, their three-dimensional structure is different. In the human body, mainly L-forms are used to build proteins, while D-forms are almost not involved in normal biology.

The team studied the effects of different amino acids on cancer cells and found that it was D-cysteine ​​that significantly slowed their growth in the laboratory. To understand the mechanism of this effect, the team of Professor Roland Lill joined the work. Researchers have found that D-cysteine ​​blocks the NFS1 enzyme in mitochondria, the structures responsible for energy production in the cell.

This enzyme is necessary for the formation of iron-sulfur clusters, important components involved in cell respiration, DNA and RNA synthesis, and maintaining the integrity of genetic material. When NFS1 is blocked, vital processes in the cancer cell are disrupted: energy production is reduced, DNA is damaged and division stops.

In experiments on mice with an aggressive form of breast cancer, the administration of D-cysteine ​​significantly slowed the growth of tumors, while no serious side effects were observed in the animals. The study results were published in the journal Nature Metabolism and point to a promising direction for developing more selective cancer treatments.