Northern blot analysis for PD-ECGF messenger RNA (mRNA) was performed on four colon cancer specimens and corresponding normal colon mucosae (same patients) and four human colon cancer cell lines (KM12SM, SW620, HT29, and NCI-H508) to determine whether colon cancer epithelium expresses PD-ECGF.
These data demonstrate that microvessel density may be associated with the depth of cancer invasion and that platelet-derived endothelial cell growth factor may play an important role in the early stage of colon cancer development through angiogenesis.
In contrast, thymidine phosphorylase mRNA was higher in cancer cells than in cancerous stroma in gastric cancer (p < 0.0001) and lower in cancer cells than in cancerous stroma in colon cancer (P = 0.0055).