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Prakrithi, P.

Publications and source records attributed to Prakrithi, P..

2 recordsLinked to original sources

Benchmarking robust spatial transcriptomics approaches to capture the molecular landscape and pathological architecture of archived cancer tissues

AbtractsApplying spatial transcriptomics (ST) to explore a vast amount of formalin-fixed paraffin-embedded (FFPE) archival cancer tissues has been highly challenging due to several critical technical issues. In this work, we optimised ST protocols to generate unprecedented spatial gene expression data for FFPE skin cancer. Skin is among the most challenging tissue types for ST due to its fibrous structure and a high risk of RNAse contamination. We evaluated tissues collected from ten years to two years ago, spanning a range of tissue qualities and complexity. Technical replicates and multiple patient samples were assessed. Further, we integrated gene expression profiles with pathological information, revealing a new layer of molecular information. Such integration is powerful in cancer research and clinical applications. The data allowed us to detect the spatial expression of non-coding RNAs. Together, this work provides important technical perspectives to enable the applications of ST on archived cancer tissues.

pathology↗

Spurious off-target signals from potential lncRNAs by 10X Visium probes

Spatial transcriptomics has revolutionized molecular profiling of tissues in a spatial context, especially in the study of cancer heterogeneity. 10X Genomics facilitates spatial gene expression profiling platforms to help work with fresh-frozen (FF) and formalin fixed paraffin embedded (FFPE) tissues. FF analysis is based on polyA capture of RNAs while FFPE analysis uses a pre-designed set of probes to capture transcripts of coding genes. Previously, we used FFPE spatial data as a negative control in a study to identify novel non-coding RNAs in FF data. Interestingly, we find and report that certain target probes used in FFPE show off-target signals from lncRNAs. The Space Ranger pipeline of 10X Visium counts the expression of these potential off-targets to be that of the corresponding target gene, some of which have known implications in cancer and its diagnosis. Therefore, relying on this technology is not ideal to investigate expression of the genes reported in this study. We hereby recommend excluding those genes in any downstream analysis of FFPE datasets and to design probes with better specificity, considering the sequence similarity between genes and non-coding RNAs.

bioinformatics↗