American doctors think they have understood why some patients on immunotherapy respond less well to treatment than others. It is the corticosteroids that would prevent the treatment from working well.
Immunotherapy is one of the newest and most powerful weapons against cancer. It prompts the immune system to recognize tumors as intruders in the body and attack them. But some patients do not respond favorably to treatment. Researchers at Cold Spring Harbor Laboratory in New York therefore sought to understand what could be hindering treatment.
One in four patients respond well to treatment
According to an Inserm survey, approximately 25% of patients on immunotherapy respond well to treatment and for a prolonged period. According to doctors in New York, glucocorticoids sometimes prescribed at the same time as immunotherapy could interfere with treatment.
“The results of our study indicate that glucocorticoids, such as cortisone, may indirectly cause some immunotherapy treatment failures by causing the production of a protein called cystatin C (CyC). Higher levels of CyC are linked to less good results from this type of therapy” explains Professor Tobias Janowicz, lead author of the study.
“Glucocorticoids are very potent suppressants of immunity and are therefore used to treat autoimmunity”, which is when the immune system attacks healthy cells. “But they can also stop immunotherapy against cancer” adds Professor Janowicz, who will continue his studies on cystatin C.
Source : How popular steroids could mess up some cancer treatmentsCold spring harbor laboratory, June 2023