Detecting known neoepitopes, gene fusions, transposable elements, and circular RNAs in cell-free RNA

Mayank Mahajan1, Martin Hemberg1

  • 1Gene Lay Institute of Immunology and Inflammation, Brigham and Women's Hospital, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02115, United States.

Abstract

Insights

This study introduces FastNeo, a novel computational method for detecting neoepitopes in cell-free RNA (cfRNA). FastNeo accurately identifies cancer biomarkers in cfRNA, enabling early detection and therapeutic insights for hepatocellular and colorectal cancers.

Area of Science:

  • Biochemistry
  • Computational Biology
  • Oncology

Background:

  • Cancer remains a leading cause of death globally, often diagnosed late due to invasive biopsy requirements and lack of early detection methods.
  • Plasma samples offer a minimally invasive source for monitoring systemic molecular signatures, with cell-free DNA (cfDNA) being a popular biomarker.
  • Cell-free RNA (cfRNA) analysis is an emerging field, providing insights into recent systemic transcriptional activity.

Purpose of the Study:

  • To develop a computational method, FastNeo, for detecting neoepitopes in human cfRNA.
  • To assess the efficacy of cfRNA-based biomarkers for cancer detection.
  • To identify neoepitopes for potential therapeutic applications.

Main Methods:

  • Development of the FastNeo computational package for neoepitope detection in cfRNA.
  • Utilized established bioinformatics pipelines for neoepitope identification.
  • Benchmarking FastNeo against standard tools like HaplotypeCaller, bcftools, and Lofreq.

Main Results:

  • FastNeo successfully detected neoepitopes and other biomarkers in cfRNA.
  • The cfRNA approach distinguished hepatocellular carcinoma patients from healthy individuals with 84% sensitivity and 79% specificity.
  • Colorectal cancer detection achieved 87% sensitivity and 80% specificity using cfRNA biomarkers.

Conclusions:

  • cfRNA analysis, powered by FastNeo, offers a promising non-invasive strategy for early cancer detection.
  • The method identifies specific neoepitopes, crucial for guiding targeted immunotherapies.
  • FastNeo enhances the utility of cfRNA as a diagnostic and therapeutic tool in oncology.

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