Figure 1.

C-Met signaling in KRAS mutant colorectal cancer. A panel of colorectal cancer cells lines with various mutations (see Table 1) was used to study baseline levels of c-Met and related proteins. Western blot analysis was performed for c-Met and related proteins, and the densities of the bands were quantified (A). Many of the cell lines, including each of the KRAS mutant cell lines, had active c-Met signaling. We then analyzed a tissue microarray containing untreated colorectal cancers. KRAS mutational status was determined by PCR. Immunohistochemistry for c-Met and p-Met was performed and quantified using the Allred system. KRAS mutant tumors had high expression of c-Met and p-Met. (B) The median and 25-75 percentile range for each protein marker. (C) Representative tumor cores showing c-Met staining are shown.