AVS 61st International Symposium & Exhibition
    Biomaterial Interfaces Tuesday Sessions
       Session BI+AS-TuA

Paper BI+AS-TuA10
Investigating Tumor Microenvironments with ToF-SIMS

Tuesday, November 11, 2014, 5:20 pm, Room 317

Session: Characterization of Biointerfaces
Presenter: Lara J. Gamble, University of Washington
Authors: L.J. Gamble, University of Washington
B. Bluestein, University of Washington
D.J. Graham, University of Washington
Correspondent: Click to Email
Cancer is a heterogeneous malignancy that manifests itself in a variety of morphological types and clinical outcomes. Current evidence indicates that tumor metabolism plays a large role in cancer onset and progression, and its causes and effects are under intense scrutiny. Furthermore, it is of interest to know where changes in tumor metabolism occur within an affected tissue. However, there are few techniques that can specifically interrogate the tumor microenvironment. We use time-of-flight secondary ion mass spectrometry (ToF-SIMS) to determine differences in the chemical makeup of the tumor microenvironment of breast cancer tumor tissue samples. Human tissue biopsies from an ongoing trial have been subtyped using DASL genome assay and grouped into subtypes of Luminal B, Basal, and ERRB2. Images and spectra have been acquired on an IONTOF TOF.SIMS V using Bi3+. The ToF-SIMS information, combined with gene expression array analysis is used to investigate the chemical differences between chemotherapeutic resistant tumors and elucidate the underlying mechanisms. Using imaging ToF-SIMS the cellular and stromal regions within the tissue can be separated out as regions of interest (ROI). Imaging principal component analysis (PCA) was successful in separating cellular regions of the tumor and stromal regions when compared with a hemotoxylin and eosin (H&E) stained adjacent tissue slice. Using the ROIs identified from imaging PCA, we compare the chemical differences between cellular and stromal microenvironment chemistry. A comparison of spectral PCA using the entire analysis area vs spectral PCA of ROIs for cellular and stromal regions of the tissue is discussed. The chemistries of these subtypes are compared using ToF-SIMS image and spectral comparison from cellular and stromal regions. A spectral comparison of ROIs between tissue samples using PCA indicates that unique fatty acids distributions may relate to a tumor phenotype and chemotherapeutic resistance.