Instability of chromosome 8 as an indicator of aggressive tumor phenotype in pancreatic cancer

Background and Objectives: Chromosomal instability is a common Feature of p ancreatic carcinoma, but its biological significance remains unclear. In th is study, we investigated the association between chromosomal instability a nd biological aggressiveness in human pancreatic cancer cells. Methods: Fluorescence in situ hybridization was performed to examine change s in chromosomal numbers in a total of 13 pancreatic cancer cell lines. We also assessed the potential for tumor aggressiveness within cancer cells by in vitro migration and invasion assay and by subcutaneous implantation int o nude mice. Results: Chromosomal instability, characterized by numerical variations in copy numbers of chromosome 8, was observed in most cell lines, and the magn itude of instability was correlated well with both motility (P < 0.001) and invasion rate (P < 0.001) of these cells. Furthermore, a significant posit ive correlation existed between chromosome instability and tumor growth in vivo (P < 0.01). Conclusions: These results suggest that the increased level of chromosomal instability may play a critical role in the development of aggressive tumor phenotype during pancreatic cancer progression. <(c)> 2001 Wiley-Liss, Inc .