A recent study sheds light on why a proven treatment for lung cancer sometimes fails to work after a certain period of time. These new insights into changes in the immune system could make it possible to treat more patients with existing, highly effective drug therapies.
Lung cancer is one of the leading causes of cancer-related death. Its treatment has developed rapidly over the last twenty years, thanks in particular to immune checkpoint inhibitor (ICI) therapy, which has improved overall survival. These drugs block checkpoint signals, enabling the body’s own immune cells to fight cancer cells more effectively. However, more than half of patients develop resistance to this treatment after the initial response, and there are few therapeutic alternatives.
What hinders immune cell defense
A study published in the scientific journal Nature Communications and led by Alessandra Curioni-Fontecedro, Head of the Oncology Unit at the Fribourg HFR Hospital and Professor at the University of Fribourg, examined the case of patients who initially responded to treatment before developing resistance.
In some patients, this resistance was due to insufficient numbers of specialized immune cells in the tumors. These cells fight the cancer, but if they are no longer active, the therapy fails. Other patients did not respond to treatment because their tumours contained too much PD-L1 protein, which hinders the immune cells’ ability to fight cancer. In yet other patients, the lack of response was explained by weakened signaling pathways.
This study helps to understand how the immune system evolves and why lung cancer treatment sometimes loses effectiveness. It should enable scientists to address resistance issues in order to improve therapy. More people with lung cancer could thus benefit from existing treatment with immune checkpoint inhibitors, and thus live longer.
Examining each patient
We need to examine each patient to determine the exact cause of his or her resistance to treatment", explains Alessandra Curioni-Fontecedro, who is conducting new studies with this in mind. I’m delighted that the Fribourg site lends itself to research activities on such a complex subject. This pioneering work requires not only the involvement of patients willing to take part in the study, but also the support and clinical advice of experienced scientists and doctors.