OBJECTIVETo test expression level and glycosylation level of OPN in HCC cell lines with different metastatic potential and HCC tissues, and investigate the correlation between the glycosylation change and the liver cancer transporting as well as its significance.

METHODSThe level of OPN expression in liver cancer tissue(6 cases of non-metastasis and 7 cases of metastasis)as well as HCC cell lines with different metastatic potential (L02, Hep3B, MHCC97L, MHCC97H, HCCLM3, HCCLM6)was identified by immunohistochemistry and Western Blot, and then OPN was purified from HCC tissues by immunoprecipitation, followed by glycosylation detection of OPN from non-metastatic and metastatic HCC tissues by multiple lectin blot. Data were analyzed by t-test and variance analysis.

RESULTSDifferent levels of OPN expression were observed in HCC cell lines with different metastatic potential (F = 5.04, P = 0.008). Additionally, OPN expression level in HCC tissues with metastasis was higher than that in non-metastasis group (t = 2.447, P < 0.05). Relative optical density value was 0.69 ± 0.21 and 0.45 ± 0.14 respectively. OPN in liver cancer tissue was successfully purified using immunoprecipitation. Followed lectin blotting result showed that OPN protein in metastasis group showed lower affinity to MAL, PHAE, DSA, ConA as compared with that in non-metastasis group (P < 0.05).

CONCLUSIONSThe expression of OPN was positively correlated with the enhanced metastasis potential of HCC. OPN from metastasis HCC tissues presented lower level of some specific glycan structures such as a2, 3- sialic acid, bisecting GlcNAc, biantennary, muti-antennary and high mannose type N-glycan structure. This study not only indicates the role of OPN in HCC metastasis for the first time, but also provide experimental support for the mechanism of the function of OPN in the transportation of liver cancer cells as well as offer potential target for clinical treatment.