Chemotherapy is most effective when senescent cells are destroyed using immunotherapy.

Cancer treatment, whether chemotherapy or other targeted treatments, in addition to killing a large number of tumor cells, leads to the formation of senescent tumor cells that do not multiply, but create a favorable environment for tumor regrowth. treatment would be more effective if these cells were eliminated using immunotherapy.

This was highlighted by IRB Barcelona researchers led by Dr. Manuel Serrano, who described how cancer cells senescent after treatment activate the protein PD-L2 to protect themselves from the immune system, while simultaneously recruiting suppressor cells. the immune system.

These suppressor cells create an inhibitory environment that prevents lymphocytes from accessing and acting against cancer cells. Thus, senescent cells promote tumor growth and limit the effectiveness of chemotherapy.

“By blocking PD-L2, we saw in mouse models that chemotherapy was more effective against cancer. This opens the door to considering the use of a potential PD-L2 inhibitor as an adjuvant in the treatment of this disease,” explains the doctor. Manuel Serrano, currently a researcher at Altos Labs (Cambridge, UK).

The study was conducted on cell lines and animal models of skin, pancreatic and breast cancer.

Cellular senescence is a process that occurs naturally with aging and has become commonplace in the context of cancer treatment. Most cancer treatments (such as chemotherapy or radiation therapy) cause multiple cell damage and, as a result, cause cellular aging, especially within the tumor.

The scientific team will now study whether aging associated with aging of the body correlates with increased levels of PD-L2.

“Although more experiments are needed to characterize the role of this molecule in various human tumors, this work has allowed us to expand our knowledge of the role of PD-L2 and the interaction of senescent cells with the immune system,” explains the postdoctoral researcher. from the same laboratory and the first author of the work, Dr. José Alberto López.

This work was carried out in collaboration with the teams of doctors Joaquín Arribas, Alena Gros and Maria Abad from the Vall d’Hebron Institute of Oncology (VHIO).