This quarter, we also learned that the immune system is a true conductor of the body’s inner workings, that AI can support physicians in tailoring treatments, and that a therapeutic combination could represent a new option for rare thymic cancers.

Traditionally, the immune system is seen as a defensive shield protecting the organism. Yet, a growing body of research shows that its role extends well beyond simple protection.
In an article published in the prestigious journal Science, Prof. Florent Ginhoux (Gustave Roussy), together with Matthias Nahrendorf (Massachusetts General Hospital and Harvard University) and Filip Swirski (Mount Sinai Hospital), sheds light on the close links between the immune system and the overall functioning of the body. Present in all tissues and able to circulate between organs, immune cells do more than combat external threats: they communicate with nerve cells, muscle cells and endocrine cells, thereby contributing to the maintenance of physiological balance.
The authors review striking examples: in the brain, immune cells influence memory; in the heart, they support mitochondrial metabolism and electrical conduction; in the gut and liver, they regulate motility and regeneration; in bones and muscles, they orchestrate repair and remodelling. Even metabolism, pregnancy and lactation appear to be modulated by their action.
This work reminds us that the immune system is not peripheral, but central. It is a full participant in physiology, weaving a communication network that shapes the functioning of the entire human body.
Immune system influence on physiology
Matthias Nahrendorf et al., Science, 389, 594–599 (2025)
This study, published in the Journal of Clinical Oncology, was conducted in collaboration with Institut Curie and coordinated by Prof. Fabrice André. It concerns women with HR-positive, HER2-negative breast cancer. It assessed a prognostic test based on artificial intelligence, developed by the start-up Spotlight Medical, in which Gustave Roussy Transfert is a shareholder.
For patients classified as high-risk within this subtype of the disease, the standard therapeutic approach relies on chemotherapy and CDK4/6 inhibitors. However, the test developed by Spotlight Medical suggests that among these women, some will not benefit from treatment intensification, as they are in fact at low risk of relapse.
To reach this conclusion, researchers relied on two cohorts of high-risk patients. The Spotlight Medical test, which analyses 10 histological or biological criteria using digitalised tumour slides, demonstrated that one patient in five was in fact at low risk of relapse. These findings were confirmed in real-world data, with 95.4% of the identified women showing no relapse after nine years of follow-up.
This test could ultimately help personalise treatment for these patients.
Identifying Patients With Low Relapse Rate Despite High-Risk Estrogen Receptor–Positive/Human Epidermal Growth Factor Receptor 2–Negative Early Breast Cancer: Development and Validation of a Clinicopathologic Assay
François-Clément Bidard et al., Journal of Clinical Oncology, 43, 3090–3101 (2025)
Thymic cancers, located in a small gland situated in the upper thorax, are rare. For patients with advanced type B3 thymoma or thymic carcinoma, two subtypes of the disease, there are unfortunately no standard therapies after the failure of platinum-based treatments.
The PECATI phase II trial, which is still ongoing, is recruiting patients with these indications in 11 hospitals in France, Italy, and Spain, to assess the antitumour activity and safety of lenvatinib, a targeted therapy that prevents tumours from forming new blood vessels, combined with pembrolizumab, an immunotherapy. All participating patients had experienced disease progression after an initial cycle of platinum-based chemotherapy.
Following the initial follow-up, the trial has already reached its primary objective, with 88.4% of patients showing no disease progression at five months, alongside observed adverse effects. These results suggest that the lenvatinib-pembrolizumab combination could offer a new therapeutic option for patients with no remaining alternatives, provided that toxicity is closely monitored.
Lenvatinib plus pembrolizumab in pretreated metastatic B3 thymoma and thymic carcinoma (PECATI): a single-arm, phase 2 trial
Remon, Jordi et al., The Lancet Oncology, Volume 26, Issue 9, 1215–1226