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Rukhovich, G.

Publications and source records attributed to Rukhovich, G..

2 recordsLinked to original sources

Segger: Fast and accurate cell segmentation of imaging-based spatial transcriptomics data

The accurate assignment of transcripts to their cells of origin remains the Achilles heel of imaging-based spatial transcriptomics, despite being critical for nearly all downstream analyses. Current cell segmentation methods are prone to over- and under-segmentation, misassign transcripts to cells, require manual intervention, and suffer from low sensitivity and scalability. We introduce segger, a versatile graph neural network based on a heterogeneous graph representation of individual transcripts and cells, that frames cell segmentation as a transcript-to-cell link prediction task and can leverage single-cell RNA-seq information to improve transcript assignments. On multiple Xenium dataset benchmarks, segger exhibits superior sensitivity and specificity, while requiring orders of magnitude less compute time than existing methods. The user-friendly open-source software implementation has extensive documentation (https://elihei2.github.io/segger_dev/), requires little manual intervention, integrates seamlessly into existing workflows, and enables atlas-scale applications.

bioinformatics↗

Integrated combinatorial functional genomics and spatial transcriptomics of tumors decodes genotype to phenotype relationships

Linking the complex genetic changes underlying cancer to relevant disease-phenotypes poses a challenge. Therefore, we present CHOCOLAT-G2P, a scalable approach that integrates multiplex in vivo functional genomics with spatial transcriptomics. By redeploying RNA-templated ligation probes of commercial spatial transcriptomics technology, we streamline mapping composite genetic alterations and transcriptome-wide phenotyping on the same tissue section on a single readout platform. Using this framework, we studied combinatorial effects of 8 perturbations that induce autochthonous mosaic liver tumors sampled from 256 genotypes. Interrogating 324 tumors across six [~]6x6 mm2 sections, we charted phenotypic landscapes of genotypically-defined tumor ecosystems, revealing zonation-associated hepatocellular carcinoma subclasses and associations between tumor subtypes and stromal-as well as immune-cell signatures. Further, we decoded epistasis within compound genotypes uncovering opposing roles of Vegfa and mutant Ctnnb1 to cholangiocarcinoma development. Thus, CHOCOLAT-G2P lays a foundation to decipher how combinations of alterations interact to reprogram tumor cells and their microenvironment within the holistic context of tissue and whole organisms. (https://chocolat-g2p.dkfz.de/).

cancer biology↗