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Biology subjects

Mohme, M.

Publications and source records attributed to Mohme, M..

3 recordsLinked to original sources

NSCLC patients with oligo-metastatic brain disease show an altered CD4 T-cells immune profile

BackgroundLung cancer is the leading cause of cancer-related deaths worldwide, with brain metastasis (BM) occurring in 40% of advanced non-small cell lung cancer (NSCLC) patients. In 15% of these patients, the brain is the only affected organ (oligo-metastasis), corresponding to improved prognosis compared to widespread disease. Thus far, it is unknown if the metastatic dissemination to the brain without systemic metastases is a consequence of the immune systems ability to control systemic tumor outgrowth. MethodsHere, we investigated the local and peripheral immune cell composition in NSCLC BM patients, and identified new immune patterns related to the occurrence of brain metastases either as oligo- or poly-metastatic disease. ResultsThe multi-parametric immune phenotyping of peripheral blood revealed a downregulation of KLRG1 in CD8+ T-cells and an increase in CD4+ TH17 cells and elevated IL-17 levels in the blood of all NSCLC BM patients compared to healthy individuals. In addition, BM patients CD4+ T cells showed less CD73 expression with reduced effector memory differentiation. Furthermore, we observed less intra-tumoral infiltration in tumor tissues and a distinctive CD4+ T-cell profile in oligo-synchronous BM, both in the tumor microenvironment and peripheral blood compared to poly-metastatic BM patients. Moreover, 5'-ectonucleotidase CD73 was significantly upregulated in CD4 and T-regulatory cells of oligo-synchronous BM. ConclusionsThese results indicate that oligo-synchronous BM exhibits a more pronounced alteration in the CD4 T-cell immune profile both locally at the tumor site and systemically. Key PointsO_LIBM patients exhibit a skewed systemic immune profile, characterized by downregulation of KLRG1 in CD8+ and induction of TH17/IL-17 axis and CD73 in CD4+ T-cells. C_LIO_LIOligo-synchronous BM displayed a distinct CD4+ T-cell profile in both TME and peripheral blood. C_LI Importance of the StudyThis study presents a novel insight into immune profiles of brain metastasis types in NSCLC patients. Examining tissues and PBMCs sheds light on the disease and uncovers unique immune responses within distinct brain metastasis patterns. This research offers valuable knowledge for improved understanding and identifying potential prognosis markers.

cancer biology↗

Epigenetic neural glioblastoma enhances synaptic integration and predicts therapeutic vulnerability

Neural-tumor interactions drive glioma growth as evidenced in preclinical models, but clinical validation is nascent. We present an epigenetically defined neural signature of glioblastoma that independently affects patients survival. We use reference signatures of neural cells to deconvolve tumor DNA and classify samples into low- or high-neural tumors. High-neural glioblastomas exhibit hypomethylated CpG sites and upregulation of genes associated with synaptic integration. Single-cell transcriptomic analysis reveals high abundance of stem cell-like malignant cells classified as oligodendrocyte precursor and neural precursor cell-like in high-neural glioblastoma. High-neural glioblastoma cells engender neuron-to-glioma synapse formation in vitro and in vivo and show an unfavorable survival after xenografting. In patients, a high-neural signature associates with decreased survival as well as increased functional connectivity and can be detected via DNA analytes and brain-derived neurotrophic factor in plasma. Our study presents an epigenetically defined malignant neural signature in high-grade gliomas that is prognostically relevant.

neuroscience↗

Polio Virotherapy of Malignant Glioma Engages the Tumor Myeloid Infiltrate and Induces Diffuse Microglia Activation

Malignant gliomas commandeer abundant inflammatory infiltrates with glioma-associated macrophages and microglia (GAMM) actively promoting tumor progression. Like all cells in the mononuclear phagocytic system, macrophages and microglia constitutively express the poliovirus receptor, CD155. Besides myeloid cells, CD155 is widely upregulated ectopically in the neoplastic compartment of malignant gliomas (and solid cancers in general). Intratumor treatment with the highly attenuated rhino:poliovirus chimera, PVSRIPO, yielded long-term survival with durable radiographic responses in patients with recurrent glioblastoma (Desjardins et al. New England Journal of Medicine, 2018). Here, we studied mechanisms of PVSRIPO immunotherapy in mouse brain tumor models to decipher contributions of myeloid vs. malignant cells to antitumor efficacy. PVSRIPO treatment caused intense engagement of the GAMM infiltrate associated with substantial, but transient tumor regression. This was accompanied by diffuse microglia activation and proliferation in the normal central nervous system (CNS) surrounding the tumor, extending to the ipsilateral and even the contralateral hemispheres. PVSRIPO-instigated microglia activation occurred against a backdrop of sustained innate antiviral inflammation, associated with induction of the PD-L1 immune checkpoint on GAMM. Combining PVSRIPO with PD1/PD-L1 blockade led to durable remissions. Our work implicates GAMM as active drivers of PVSRIPO-induced antitumor inflammation and reveals profound and widespread neuroinflammatory activation of the CNS-resident myeloid compartment by PVSRIPO.

cancer biology↗