To better understand the biology of mir-17~92 deficient pancreatic cancer cells, we generated a collection of cell lines from KPC and 17KPC tumors. Evaluation of cell invasion in transwell assays demonstrated that 17KPC cell lines have reduced ability to invade through Matrigel relative to KPC cell lines (Figure 5A). However, no differences were observed between the two genotypes in their ability to migrate across uncoated membranes (Figure 5B). Additionally, there were no significant differences in the proliferation, anchorage independent growth, or survival phenotypes of KPC and 17KPC cell lines (Figure 5C–5F). These data agree with the suggestion that 17KPC tumors display delayed invasion in vivo, and suggest a specific defect in the ability of tumor cells to manipulate extracellular matrix.