Biology subjects

Kahelin, E.

Publications and source records attributed to Kahelin, E..

3 recordsLinked to original sources

bioRxiv2025

Multi-modal characterization of transcriptional programs that drive metastatic cascades to solid sites and ascites in ovarian cancer

Ovarian high-grade serous carcinoma (HGSC) is characterized by extensive intra-peritoneal dissemination and tumor heterogeneity. In the metastatic cascade, tumors utilize several transcriptional programs to translocate and survive in distant tissues. Here, we analyzed multi-modal, real-world data from 350 tumor samples across 160 patients with HGSC to identify transcriptional programs that drive intra-peritoneal metastasis and heterogeneity. We identified nine transcriptional programs, including those regulating epithelial-mesenchymal transition and immune modulation and cytoskeletal reorganization, which shape distinct metastatic trajectories to solid and ascitic environments and are associated to treatment response. Our results reveal pronounced intra-patient transcriptional heterogeneity, which in some cases surpassed inter-patient heterogeneity, highlighting the importance of multi-site sampling for accurate prognostication and combinatorial treatments in HGSC. Our extensive characterization offers novel insights into intra-peritoneal metastasis with significant prognostic implications, reveals histomorphological biomarkers for patient stratification and paves the way for innovative therapeutic strategies aimed at impairing cancer cell adaptability and limiting metastasis.

cancer biology↗

bioRxiv2024

Single-cell spatial atlas of high-grade serous ovarian cancer unveils MHC class II as a key driver of spatial tumor ecosystems and clinical outcomes

The tumor microenvironment (TME) is a complex network of interactions between malignant and host cells, yet its orchestration in advanced high-grade serous ovarian carcinoma (HGSC) remains poorly understood. We present a comprehensive single-cell spatial atlas of 280 metastatic HGSCs, integrating high-dimensional imaging, genomics, and transcriptomics. Using 929 single-cell maps, we identify distinct spatial domains associated with phenotypically heterogeneous cellular compositions, and demonstrate that immune cell co-infiltration at the tumor-stroma interface significantly influences clinical outcomes. To uncover the key drivers of the tumor ecosystem, we developed CEFIIRA (Cell Feature Importance Identification by RAndom forest), which identified tumor cell-intrinsic MHC-II expression as a critical predictor of prolonged survival, independent of clinicomolecular profiles. Validation with external datasets confirmed that MHC-II-expressing cancer cells drive immune infiltration and orchestrate spatial tumor-immune interactions. Our atlas offers novel insights into immune surveillance mechanisms across HGSC clinicomolecular groups, paving the way for improved therapeutic strategies and patient stratification.

cancer biology↗

bioRxiv2024

Chemotherapy induces myeloid-driven spatial T-cell exhaustion in ovarian cancer

To uncover the intricate, chemotherapy-induced spatiotemporal remodeling of the tumor microenvironment, we conducted integrative spatial and molecular characterization of 97 high-grade serous ovarian cancer (HGSC) samples collected before and after chemotherapy. Using single-cell and spatial analyses, we identify increasingly versatile immune cell states, which form spatiotemporally dynamic microcommunities at the tumor-stroma interface. We demonstrate that chemotherapy triggers spatial redistribution and exhaustion of CD8+ T cells due to prolonged antigen presentation by macrophages, both within interconnected myeloid networks termed "Myelonets" and at the tumor stroma interface. Single-cell and spatial transcriptomics identifies prominent TIGIT-NECTIN2 ligand-receptor interactions induced by chemotherapy. Using a functional patient-derived immuno-oncology platform, we show that CD8+T-cell activity can be boosted by combining immune checkpoint blockade with chemotherapy. Our discovery of chemotherapy-induced myeloid-driven spatial T-cell exhaustion paves the way for novel immunotherapeutic strategies to unleash CD8+ T-cell-mediated anti-tumor immunity in HGSC.

cancer biology↗