Systematic identification of cancer-specific MHC-binding peptides with RAVEN

Michaela C Baldauf1, Julia S Gerke1, Andreas Kirschner2

  • 1Faculty of Medicine, Max-Eder Research Group for Pediatric Sarcoma Biology, Institute of Pathology, LMU Munich, Munich, Germany.

Oncoimmunology
|September 20, 2018
PubMed

Insights

Researchers developed RAVEN software to identify cancer-specific gene (CSG)-encoded peptides for targeted immunotherapy. This tool analyzes transcriptome data to find peptides with high Major Histocompatibility Complex (MHC) affinity, aiding in treating cancers lacking traditional neo-antigens.

Area of Science:

  • Oncology
  • Immunology
  • Bioinformatics

Background:

  • Immunotherapy offers revolutionary potential in anti-cancer treatment, contingent on identifying specific therapeutic targets.
  • Oligo-mutated cancers, lacking neo-antigens from protein mutations, present a challenge for current targeted immunotherapies.
  • Cancer-specific genes (CSGs) encode peptides that can serve as potential targets for novel immunotherapeutic strategies.

Purpose of the Study:

  • To develop and present an automated algorithm and user-friendly software, RAVEN, for identifying cancer-specific gene (CSG)-encoded peptides with high Major Histocompatibility Complex (MHC) affinity.
  • To create a comprehensive catalog of cancer-specific, highly MHC-affine peptides across diverse cancer types.
  • To provide a freely accessible software tool for researchers to apply the RAVEN algorithm to any gene expression dataset for advancing anti-cancer immunotherapy.

Main Methods:

  • Developed RAVEN (Rich Analysis of Variable gene Expressions in Numerous tissues) software for automated identification of CSG-encoded peptides from transcriptome data.
  • Applied RAVEN to a dataset of 2,678 microarrays from 50 tumor entities and 71 normal tissues, focusing on oligo-mutated pediatric cancers.
  • Validated CSG expression in cell lines and tissue microarrays, predicted peptide-MHC affinity, and excluded sequence identity using the UniProt database; validated peptide binding in T2-cell assays.

Main Results:

  • RAVEN successfully identified established and novel cancer-specific genes (CSGs) across 50 tumor types, including those relevant to oligo-mutated cancers.
  • The software predicted numerous CSG-encoded peptides with high affinity to Major Histocompatibility Complexes (MHCs).
  • Experimental validation confirmed the binding kinetics of selected peptides to MHCs, comparable to a known immunogenic peptide.

Conclusions:

  • RAVEN software provides an efficient and systematic method for discovering cancer-specific peptides with high MHC affinity from transcriptome data.
  • The study generated a valuable catalog of cancer-specific, MHC-affine peptides across 50 cancer types, suitable for targeted immunotherapy development.
  • The freely available RAVEN software and peptide libraries represent a significant resource for advancing anti-cancer immunotherapy, particularly for challenging cancer types.

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