Biology subjects

Schallenberg, S.

Publications and source records attributed to Schallenberg, S..

4 recordsLinked to original sources

bioRxiv2024

A quantitative tumor-wide analysis of morphological heterogeneity of colorectal adenocarcinoma

Morphologic heterogeneity of colorectal adenocarcinoma (CRC) is poorly understood. Previously, we identified morphological patterns associated with CRC molecular subtypes, and showed that these patterns have distinct molecular motifs (Budinska et al., 2023). Here, we evaluated the heterogeneity of these patterns across CRC. Three pathologists evaluated dominant, secondary, and tertiary morphology on four different tissue blocks per tumor in a pilot set of 22 CRCs (n=88). An artificial intelligence (AI) image analysis tool was trained using the pathologist-rated tumors to assess the morphologic heterogeneity on an expanded set of 161 CRCs (644 images). Heterogeneity was expressed as a combination of morphology patterns (morphotypes) across slides and normalized Shannons index (NSI). All pathologists agreed that the majority of tumors had 2-3 different dominant morphotypes, and that the complex tubular (CT) morphotype was the most common. AI analysis confirmed these observations in the full set. CT morphotype combined with all other dominant morphotypes within a tumor. Desmoplastic (DE) morphotype was rarely dominant and rarely combined with other dominant morphotypes. Mucinous (MU) was most often combined with solid/trabecular (TB) and papillary (PP). Most tumors showed medium or high NSI, but without clinical consequence. The proportion of DE morphotype was associated with higher T-stage, N-stage, metastasis, AJCC-stage, and shorter relapse-free survival, and MU morphotype was associated with higher grade, right side, microsatellite instability, and shorter overall survival. In conclusion, we observed high intratumoral morphological heterogeneity of CRC, and that not heterogeneity per se, but the proportion of certain morphotypes showed associations with clinical outcome. This has implications for molecular profiling of CRC.

cancer biology↗

bioRxiv2023

Open-ST: High-resolution spatial transcriptomics in 3D

Spatial transcriptomics (ST) methods have been developed to unlock molecular mechanisms underlying tissue development, homeostasis, or disease. However, there is a need for easy-to-use, high-resolution, cost-efficient, and 3D-scalable methods. Here, we report Open-ST, a sequencing-based, open-source experimental and computational resource to address these challenges and to study the molecular organization of tissues in 3D. In mouse brain, Open-ST captured transcripts at subcellular resolution and reconstructed cell types. In primary tumor and patient-matched healthy/metastatic lymph nodes, Open-ST captured the diversity of immune, stromal and tumor populations in space. Distinct cell states were organized around cell-cell communication hotspots in the tumor, but not the metastasis. Strikingly, the 3D reconstruction and multimodal analysis of the metastatic lymph node revealed spatially contiguous structures not visible in 2D and potential biomarkers precisely at the 3D tumor/lymph node boundary. We anticipate Open-ST to accelerate the identification of spatial molecular mechanisms in 2D and 3D.

systems biology↗

bioRxiv2023

Osteopontin in colitis-associated carcinoma

Patients with ulcerative colitis (UC) and Crohns disease (CD) face a lifelong risk of developing colitis-associated carcinoma (CAC). Current insights into CAC development originate from murine CAC models, while human CAC studies primarily focus on mutational analysis of patient samples. Although the mutational landscape reveals distinct patterns and frequencies compared to colorectal cancer, it falls short in elucidating the inflammatory mechanisms of CAC development. Consequently, we adopted a multi-omics approach to unravel CAC carcinogenesis from an immunological perspective. Our data revealed a robust upregulation of SPP1 gene in CAC at both RNA and protein levels, expressed by CD68+ macrophages. In vitro OPN stimulation demonstrated no direct effect on intestinal epithelial organoids. However, the mutually exclusive spatial location of SPP1/OPN+ macrophages and CD8+ T cells suggests a crucial indirect role of SPP1/OPN in mediating an immunosuppressive tumour microenvironment.

cancer biology↗

bioRxiv2023

High-resolution molecular atlas of a lung tumor in 3D

Cells live and interact in three-dimensional (3D) cellular neighborhoods. However, histology and spatial omics methods mostly focus on 2D tissue sections. Here we present a 3D spatial atlas of a routine clinical sample, an aggressive human lung carcinoma, by combining in situ quantification of 960 cancer-related genes across [~]340,000 cells with measurements of tissue-mechanical components. 3D cellular neighborhoods subdivided the tumor microenvironment into tumor, stromal, and immune multicellular niches. Interestingly, pseudotime analysis suggested that pro-invasive epithelial-to-mesenchymal transition (EMT), detected in stroma-infiltrating tumor cells, already occurred in one region at the tumor surface. There, myofibroblasts and macrophages specifically co-localized with pre-invasive tumor cells and their multicellular molecular signature identified patients with shorter survival. Moreover, cytotoxic T-cells did not infiltrate this niche but colocalized with inhibitory dendritic and regulatory T cells. Importantly, systematic scoring of cell-cell interactions in 3D neighborhoods highlighted niche-specific signaling networks accompanying tumor invasion and immune escape. Compared to 2D, 3D neighborhoods improved the characterization of immune niches by identifying dendritic niches, capturing the 3D extension of T-cell niches and boosting the quantification of niche-specific cell-cell interactions, including druggable immune checkpoints. We believe that 3D communication analyses can improve the design of clinical studies investigating personalized, combination immuno-oncology therapies.

systems biology↗