Abstract

Met protein is a transmembrane 190 kD heterodimer with tyrosine kinase activity, encoded by c-Met oncogene. It serves as a high affinity receptor for hepatocyte growth factor (HGF)/scatter factor (SF), a cytokine which stimulates cell proliferation, motility, and invasion. In this study, we immunohistochemically evaluated the expression of Met/hepatocyte growth factor receptor in colorectal cancers. Met protein was expressed in 31 of 72 patients (43.1%). The staining pattern was cytoplasmic in nature, present throughout the tumor, and showed variable intensity from case to case. The relationship between the expression rate and intensity, and age and sex of patients, tumor size (p=0.645), tumor site (p=0.902) and tumor differentiation (p=0.844) was not statistically significant. The expression rate and intensity were significantly correlated with lymphovascular invasion (p=0.001), lymph node metastasis (p=0.010), depth of invasion (0.019), and stage (p=0.023). Cytoplasmic accumulation of Met protein was not associated with enhanced PCNA index of tumor cells (p=0.052). These results suggest that Met protein may play an important role in the invasion and metastasis of colorectal cancer cells.

• Keywords: Colorectal;Carcinoma;Met protein;Hepatocyte growth factor;PCNA;