Protein differences in human pancreatic cancer cell lines with diverse metastatic potential

M. A. Schwalke, C. M. Doremus, R. Bleday, H. J. Wanebo and M. P. Vezeridis
Department of Surgery, Brown University, Providence, RI.

High-resolution two-dimensional polyacrylamide gel electrophoresis was performed on the pancreatic cell lines SG, SG-R, FG, and L3.5, which when injected into the spleen of nude mice produced hepatic metastases in 0%, 20%, 64%, and 100% of the animals, respectively. A total of 981 proteins were quantitatively identified. In the highly metastatic lines, 13 proteins were present in statistically significant greater quantities, while 4 proteins were present in statistically significant greater quantities in the cell lines with a low metastatic potential. Two proteins were unique to the highly metastatic lines, while 16 proteins were unique to the lines with a low metastatic potential. These results suggest that there are considerable quantitative and qualitative differences in the cellular proteins of human pancreatic cancer cell lines with a varying metastatic potential and imply a biochemical basis to tumor heterogeneity and metastases.