Single-cell profiling in ovarian germ cell and sex cord-stromal tumours
Menée à partir du séquençage à l'échelle cellulaire de l'ARN de 66 919 cellules issues de 12 échantillons tumoraux prélevés sur 7 patientes adultes atteintes d'une tumeur germinale ovarienne ou d'une tumeur des cordons sexuels et du stroma de l'ovaire, cette étude caractérise les fibroblastes et les sous-types des cellules immunitaires du microenvironnement tumoral
Background : The tumour microenvironment of rare ovarian germ cell tumours (OGCT) and sex-cord stromal tumours (SCST) remains unexplored. To better understand their immune and stromal landscape, we constructed a blueprint using single-cell RNA sequencing (scRNA-seq).
Methods : We performed scRNA-seq of 66, 919 cells from twelve fresh tumour samples: seven adult granulosa cell tumour (aGSCT), one juvenile GSCT (jGSCT), one Sertoli-Leydig (SL) tumour, two immature teratoma (IT) and one dysgerminoma (DG). We characterised immune cell subtypes and fibroblasts based on their specific marker genes. Validation included combined positive score (CPS) of 46 OGCTs and 66 SCSTs, and bulk RNA sequencing (n = 32).
Results : Cell clustering and annotation revealed a immune-activated microenvironment in DG, driven by PD-1- exhausted T cells, reflected in high CPS (≥10) and upregulated immune pathways. IT samples displayed no immunoreactive profile, consistent with a negative CPS. aGSCTs exhibited a fibroblast-enriched, immune-desert phenotype, with low T cell infiltration and increased immunosuppressive LYVE1 and CX3CR1+ macrophages, corresponding to negative CPS.
Conclusion : We constructed a detailed blueprint of the OGCT and SCSTs microenvironment of, elucidating potential modulators that shape their immune landscape. The immune-suppressive environment in aGSCTs likely limits immunotherapy response, as immunosuppressive macrophages inhibit T cell expansion along with EMT activation and fibroblast predominance.
British Journal of Cancer , résumé 2025