Expression and role of thrombospondin-1 in colorectal cancer.

Thrombospondin-1 (TSP1) inhibits angiogenesis and activates transforming growth factor beta-1 (TGF beta-1). The expression and role of TSP1 remain controversial. On 132 colorectal cancer specimens, we performed immunohistochemical staining of TSP1, TGF beta-1, latency-associated peptide (LAP) and CD34, besides performing in situ hybridization (ISH) of TSP1.