Lara Gamble oral presentation (OB3-Tue3-1-5)
Characterizing Tumors and Tumor Microenvironments
University of Washington, Box 351653, WA 98195 Seattle, United States
Solid tumors are not simply masses of malignant cells, but are a structurally complex system, composed of a myriad of cells. The interactions between malignant cells and the non-transformed cells form the tumor microenvironment. Major implications connected to tumor progression and drug resistances are associated with the tumor microenvironment. Here, a combination of techniques including imaging time-of-flight secondary ion mass spectrometry (ToF-SIMS), second harmonic generation (SHG) microscopy, and H&E staining are used to analyze tumors (human breast and pancreatic cancer biopsies from a mouse model). Using imaging ToF-SIMS it is possible to relate changes in the composition and distribution of metabolic related molecules with tumor development. Regions of interest (ROIs) of the tumor and surrounding tissue are investigated with imaging principal components analysis (PCA) to identify peaks that correspond to species of interest. These ROIs can be utilized to compare similar regions from different tissue samples. Additionally, regions identified by analysis and PCA are cross-referenced against immunohistochemical, H&E. PCA analysis of ToF-SIMS image data separate tumor from surrounding tissue and reveal the differences in chemistries between the two regions. For example, metabolic analyses showed that pancreatic tumor islets exhibited increased intensities of phenylalanine, tyrosine, adenine, and long chain phosphatidylcholine lipids (30:0, 32:1, 32:2) when compared to control islets.