Expression and quantification of LYVE-1 in human colorectal cancer

The recent discovery of a new hyaluronan (HA) receptor, LYVE-1 (lymphatic vessel endothelial HA receptor), has been received with great interest regarding its specific expression in the lymphatic system. The process of lymphangiogenesis or the formation of new lymphatics in tumours is important because it serves as a major route for cancer metastasis. Therefore, methods to quantify lymphangiogenesis by measuring LYVE-1 have been studied extensively in searching for its possible role in cancer diagnosis, prognosis and even targeted treatment of lymphatic tumour metastasis. Here we report a quantitation study on lymphangiogenesis by either quantitative PCR or immunohistochemistry approaches in detecting LYVE-1 expression in human colorectal tumour. Real-time quantitative polymerase chain reaction (RTQ-PCR) was carried out to quantify LYVE-1 levels in colorectal cancer samples. Also, the same specimen was observed for LYVE-1 expression by immunohistochemical stain. By RTQ-PCR amplification, LYVE-1 was highly expressed in colorectal specimens and LYVE-1 signal from non-cancer tissue of normal control was much weaker by conventional RTPCR. Immunohistochemical stain showed that LYVE-1 was significantly expressed in cancer tissues (especially in the margin region of cancer), whereas in non-cancer specimens fewer positive stains were revealed. The results suggested that the LYVE-I molecule was expressed significantly in colorectal specimens, which may imply a new marker for a malignant situation.