Application of Two-Dimensional Difference Gel Electrophoresis to Identify Protein Changes between Center, Margin, and Adjacent Non-Tumor Tissues Obtained from Non-Small-Cell Lung Cancer with Squamous Cell Carcinoma Subtype

Lung cancer is responsible for the most cancer-related mortality worldwide and the mechanism of its development is poorly understood. Proteomics has become a powerful tool offering vital knowledge related to cancer development. Using a two-dimensional difference gel electrophoresis (2D-DIGE) approach, we sought to compare tissue samples from non-small-cell lung cancer (NSCLC) patients, exactly squamous cell carcinoma (SCC), taken from the tumor center and tumor margin and control (adjacent non-tumor) tissues. We found and 21 spots representing 20 proteins differentiating center and margin. We found 111 differentially expressed protein spots representing 95 proteins; 84, 7, and 20 spots differed between the control and center and margin, control and center, and control and margin, respectively. Nine significant canonical pathways were identified, including hypoxia-inducible factor-1α signaling, thyroid hormone biosynthesis, and phagosome maturation. Several pathways related to disease and function were identified as related to cell death and survival, and several related to cancer, organismal injury, and abnormalities. Proteins differentiating the tumor center and tumor margin were linked to cancer invasion and progression, including cell migration, adhesion and invasion, cytoskeletal structure, protein folding, anaerobic metabolism, tumor angiogenesis, epithelialmesenchymal transition, epithelial adherens junctions, and inflammatory responses.