For the first time, scientists have identified a mechanism that allows cancer cells to evade the immune system. The discovery was made by a group of researchers from the National Cancer Center in Singapore, who published a scientific study on this matter in the journal “Nature Communications”.

Professor Gopal Iyer, lead author of the study and head of head and neck surgery at the National Cancer Center in Singapore, said the immune system detects and destroys abnormal cells, such as cancer cells, but in some cases these “evade” the immune system.

This is possible due to the mechanism of metastasis, the process by which cancer cells detach from the primary tumor and regenerate in other parts of the body, making cancer treatment more difficult, Il Messaggero reported, citing Rador.

For this reason, the team decided to study the early onset of metastasis, which usually occurs when cancer cells are found in lymph nodes in close proximity to the primary tumor.

Then scientists discovered the presence of pre-metastatic cells in the tumors, capable of moving from the place of origin to other parts of the body, passing through the lymph nodes.

The researchers then noticed that a significant portion of the CD8+ lymphocytes—cells tasked with identifying and destroying abnormal cells (including cancer cells)—were “exhausted” and unable to fulfill their protective role because, after being repeatedly destroyed by cancer, they have lost their effectiveness.

“Like an employer forcing its employees to work 24-hour, grueling shifts, cancer forces immune cells to work overtime, and the immune cells become exhausted, unable to function normally,” Professor Iyer said.

The researchers also discovered that when cancer cells and immune cells communicate with each other through special receptors, the infected cells emit a signal that is read by the latter as “don’t eat me.”

Immune cells, – reports the author of the study, – can be partially “reactivated” using inhibitors of the PD-1 class. But despite such treatment, many of them are still too “tired” to continue destroying the infected cells.

The importance of the opening of the National Cancer Center in Singapore is to demonstrate that despite the effects of cancer, the body’s immune system continues to work, albeit with reduced efficiency. Therefore, studies have shown that immune cells can always be reactivated, even at secondary moments.

“Our research shows that we can fight cancer with a wider arsenal of ‘weapons,'” Iyer concluded. (photo: Jezper | Dreamstime.com)