Peak learning of mass spectrometry imaging data using artificial neural networks.

Journal: Nature communications
Published Date:

Abstract

Mass spectrometry imaging (MSI) is an emerging technology that holds potential for improving, biomarker discovery, metabolomics research, pharmaceutical applications and clinical diagnosis. Despite many solutions being developed, the large data size and high dimensional nature of MSI, especially 3D datasets, still pose computational and memory complexities that hinder accurate identification of biologically relevant molecular patterns. Moreover, the subjectivity in the selection of parameters for conventional pre-processing approaches can lead to bias. Therefore, we assess if a probabilistic generative model based on a fully connected variational autoencoder can be used for unsupervised analysis and peak learning of MSI data to uncover hidden structures. The resulting msiPL method learns and visualizes the underlying non-linear spectral manifold, revealing biologically relevant clusters of tissue anatomy in a mouse kidney and tumor heterogeneity in human prostatectomy tissue, colorectal carcinoma, and glioblastoma mouse model, with identification of underlying m/z peaks. The method is applied for the analysis of MSI datasets ranging from 3.3 to 78.9 GB, without prior pre-processing and peak picking, and acquired using different mass spectrometers at different centers.

Authors

  • Walid M Abdelmoula
    Surgical Molecular Imaging Laboratory, Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
  • Begona Gimenez-Cassina Lopez
    Surgical Molecular Imaging Laboratory, Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
  • Elizabeth C Randall
    Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
  • Tina Kapur
    Harvard Medical School, Boston MA, USA.
  • Jann N Sarkaria
    Department of Radiation Oncology, Mayo Clinic, 200 First St SW, Rochester, MN, 55902, USA.
  • Forest M White
    Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
  • Jeffrey N Agar
    Department of Chemistry and Chemical Biology, Northeastern University, 412 TF (140 The Fenway), Boston, MA, 02111, USA.
  • William M Wells
  • Nathalie Y R Agar
    Surgical Molecular Imaging Laboratory, Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA. Nathalie_Agar@dfci.harvard.edu.