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Biology subjects

Richard, D. J.

Publications and source records attributed to Richard, D. J..

2 recordsLinked to original sources

Deep learning-based pan-cancer classification model reveals cancer-specific gene expression signatures

The identification of cancer-specific biomarkers and therapeutic targets is one of the primary goals of cancer genomics. Thousands of cancer genomes, exomes, and transcriptomes have been sequenced to date. In this study, we conducted a pan-cancer analysis of transcriptome datasets from 37 cancer types provided by The Cancer Genome Atlas (TCGA) in an effort to identify cancer-specific gene expression signatures. We employed deep neural networks to train a model on the transcriptome profile datasets for all cancer types. The model was validated, and its predictive accuracy was determined using an independent dataset, achieving > 97% prediction accuracy across cancer types. This strongly suggests that there are distinct gene expression signatures associated with various cancer types. We interpreted the model using SHapley Additive exPlanations (SHAP) to identify specific gene signatures that significantly contributed to the classification of cancer types. In addition to known biomarkers, we identified several novel biomarkers in different cancer types. These cancer-specific gene signatures are valuable candidates for future studies of their potential utility as cancer biomarkers and putative therapeutic targets.

bioinformatics↗

A biophysical and structural analysis of DNA binding by oligomeric hSSB1 (NABP2/OBFC2B)

The oxidative modification of DNA can result in the loss of genome integrity and must be repaired to maintain overall genomic stability. We have recently demonstrated that human single stranded DNA binding protein 1 (hSSB1/NABP2/OBFC2B) plays a crucial role in the removal of 8-oxo-7,8-dihydro- guanine (8-oxoG), the most common form of oxidative DNA damage. The ability of hSSB1 to form disulphide-bonded tetramers and higher oligomers in an oxidative environment is critical for this process. In this study, we have used nuclear magnetic resonance (NMR) spectroscopy and surface plasmon resonance (SPR) experiments to determine the molecular details of ssDNA binding by oligomeric hSSB1. We reveal that hSSB1 oligomers interact with single DNA strands containing damaged DNA bases; however, our data also show that oxidised bases are recognised in the same manner as undamaged DNA bases. We further demonstrate that oxidised hSSB1 interacts with ssDNA with a significantly higher affinity than its monomeric form confirming that oligomeric proteins such as tetramers can bind directly to ssDNA. NMR experiments provide evidence that oligomeric hSSB1 is able to bind longer ssDNA in both binding polarities using a distinct set of residues different to those of the related SSB from Escherichia coli.

biochemistry↗