[A study on correlation of hepatic metastasis of colorectal cancer to vascular endothelial growth factor, angiopoietin-2, and fibronectin].

OBJECTIVE: To study the correlation of hepatic metastasis of colorectal cancer to vascular endothelial growth factor (VEGF), angiopoietin- 2 and fibronectin (FN). METHODS: The transcription and expression of VEGF, angiopoietin- 2 and FN were detected by semiquantitative reverse transcription- polymerase chain reaction (SQRT- PCR) and immunohistochemical staining in the specimens from sixty patients with colorectal cancer. RESULTS: The mRNA transcription and expression levels of VEGF, angiopoietin- 2 and FN in colorectal cancer tissues were obviously higher than those in paratumor normal tissues P< 0.05. The transcription and expression levels of VEGF were correlated with tumor invasion P< 0.05,Dukes' stage P< 0.05,and lymph node and/or hepatic metastasis P< 0.05. Angiopoietin expression and transcription levels were correlated with tumor differentiation. The expression of FN in extra cellular matrix (ECM) was significantly higher (P< 0.05),whereas ECM in basement membrane was significantly lower in cancer tissues than that in paratumor normal tissues (P< 0.05),which both were correlated with tumor invasion P< 0.05,Dukes' stage P< 0.05,and lymph node metastasis P< 0.05. Absence of FN protein in basement membrane was also correlated with hepatic metastasis. CONCLUSION: Colorectal cancer cells can secrete VEGF and contribute to metastasis and proliferation of tumor by stimulating the growth of tumor vessel. Both of VEGF and angiopoietin- 2 contribute to angiogenesis and the decrease of FN in basement membrane of cancer tissue is an important primary factor of hepatic metastasis.