MmCMS: mouse models' consensus molecular subtypes of colorectal cancer

Raheleh Amirkhah1, Kathryn Gilroy2, Sudhir B Malla1

  • 1The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, UK.

British Journal of Cancer
|January 30, 2023
PubMed
Abstract

Insights

Researchers developed new methods to classify mouse colorectal cancer (CRC) models according to human subtypes. A pathway-level approach is best for aligning mouse models with human CRC consensus molecular subtypes (CMS) for drug testing.

Area of Science:

  • Oncology
  • Bioinformatics
  • Translational Research

Background:

  • Colorectal cancer (CRC) is classified into four consensus molecular subtypes (CMS1-4).
  • Genetically engineered mouse models are crucial for pre-clinical cancer research.
  • A reliable method for dual-species (human-to-mouse) CRC classification is lacking.

Purpose of the Study:

  • To develop and evaluate methods for classifying mouse colorectal cancer (CRC) tissues according to human consensus molecular subtypes (CMS).
  • To identify the optimal classification approach for aligning mouse models with human CRC subtypes for pre-clinical drug testing.

Main Methods:

  • Utilized transcriptional data from human (TCGA cohort) and mouse CRC tumors.
  • Employed random forest and nearest template prediction algorithms with gene ontology collections.
  • Developed and assessed three dual-species classifiers: MmCMS-A (gene-level), MmCMS-B (ontology-level), and MmCMS-C (pathway-level).

Main Results:

  • All developed classifiers could identify CMS4-like (stromal-rich) tumors in mice.
  • The gene-level classifier (MmCMS-A) failed to accurately classify epithelial-like subtypes (CMS2/3) in mouse tumors.
  • Pathway-level classification approaches proved superior for mouse CRC subtyping.

Conclusions:

  • Pathway-level classifiers are optimal for applying human-based transcriptional classification to mouse tumor data.
  • The study provides an R package to aid researchers in selecting appropriate mouse models for human CRC subtype research.
  • Accurate alignment of mouse models to human CRC subtypes enhances the reliability of pre-clinical drug testing.