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Koskivuo, I.

Publications and source records attributed to Koskivuo, I..

3 recordsLinked to original sources

Breast Cancer Remodels Lymphatics in Sentinel Lymph Nodes

Cancer metastasis to sentinel lymph nodes (LNs) is often the first marker of potential disease progression. Although it is recognized that tumor-induced lymphangiogenesis facilitates metastasis into LNs in murine models, tumor-induced alterations in human lymphatic vessels remain obscure. We used single-cell RNA sequencing to profile lymphatic endothelial cell (LEC) subsets in paired metastatic and non-metastatic LNs obtained from patients with treatment-naive breast cancer. Tumor metastasis decreases immunoregulatory LEC subsets, such as PD-L1+ subcapsular sinus LECs, while inducing an increase in capillary-like CD200+ HEY1+ LECs. Matrix Gla protein (MGP) was the most upregulated gene in metastatic LN LECs, and its expression on LECs was TGF-{beta} and VEGF dependent. Upregulated MGP promotes cancer cell adhesion to LN lymphatics. Thus, breast cancer cell metastasis to LNs remodels LEC subsets in human LNs and escalates MGP expression, potentially facilitating cancer cell dissemination through the lymphatic system.

immunology↗

Secreted Clever-1 Modulates T Cell Responses and Impacts Cancer Immunotherapy Efficacy

Clever-1 functions as a scavenger and adhesion receptor, promoting tolerogenic activities in macrophages and subsets of endothelial cells, thereby contributing to cancer progression. High Clever-1 expression associates with resistance to immune checkpoint inhibitors and combined targeting of Clever-1 with anti-PD-1 enhances response in refractory mouse tumor models. A Clever-1-targeting humanized IgG4 antibody, bexmarilimab, is investigated in clinical trials as a macrophage-reprogramming therapy to treat solid tumors (NCT03733990) and hematological malignancies (NCT05428969). Here we describe a secreted form of (s)Clever-1 enriched in plasma of cancer patients, that was decreased upon bexmarilimab treatment. With the production of a recombinant sClever-1, mimicking the one found in human plasma, we show that sClever-1 can selectively bind activated T cells and disrupt T cell receptor signalling leading to impaired Th1 expansion. We demonstrate that sClever-1 binds to insulin growth factor 2 receptor (IGF2R) on T cells via its mannose-6-phosphate modification and further show that sClever-1 contributes to the immunosuppressive properties of macrophage-secreted extracellular vesicles, driving T cell tolerance and impairing anti-PD-1 efficacy. These findings suggest that Clever-1 exerts a systemic immunosuppressive effect independently of the cells it is expressed on, highlighting its potential as a target in cancer immunotherapy and a valuable biomarker for disease detection.

immunology↗

Patient-derived tumor explant models of tumor immune microenvironment reveal distinct and reproducible immunotherapy responses

Tumor-resident immune cells play a crucial role in eliciting anti-tumor immunity and immunomodulatory drug responses, yet these functions have been difficult to study without tractable models of tumor immune microenvironment (TIME). Patient-derived ex vivo models contain authentic resident immune cells and therefore, could provide new mechanistic insights into how TIME responds to tumor or immune cell-directed therapies. Here, we assessed the reproducibility and robustness of immunomodulatory drug responses across two different ex vivo models of breast cancer TIME and one of renal cell carcinoma. These independently developed TIME models were treated with a panel of clinically relevant immunomodulators, revealing remarkably similar changes in gene expression and cytokine profiles among the three models in response to T cell activation and STING-agonism while still preserving individual patient-specific response patterns. Moreover, we found two common core signatures of adaptive or innate immune responses present across all three models and both types of cancer, potentially serving as a benchmark for drug-induced immune activation in ex vivo models of TIME. The robust reproducibility of immunomodulatory drug responses observed across diverse ex vivo models of TIME underscores the significance of human patient-derived models in elucidating the complexities of antitumor immunity and therapeutic interventions.

immunology↗