Correlation between the expression of Gal: 3-O-sulfotransferase-2 and metastasis potentials of cancer cells

The Gal: 3-O-sulfotransferase-2 (GP3ST) was a newly cloned sulfotransferase and its biological significance remained unknown. The expression levels in different metastatic potential tumor cells and larynx cancer tissues were investigated. A significantly higher expression level of GP3ST and sulfated glycocojugates were observed in highly metastastic cancer cells and larynx cancer tissues with lymph node metastasis than those in lowly metastatic cancer cells and ones without metastasis (P < 0.05, n = 42). GP3ST expression was further suppressed by targeted RNAi technology in hepatocarcinoma cells SMMC7721. It was found that the morphology of SMCC7721 cells transfected with RNAi-GP3ST was changed from polygon to shuttle shape and the adhesion ability to HUVEC induced by TNF-α and sL-selectin was significantly decreased. Furthermore, the decreased expression of GP3ST could lead to expression inhibition of integrin subunit αV, but didn't affect the expression of integrin subunit β3 by Western blot analysis and RT-PCR. The result of higher αV expression in high metastatic cells than in low metastatic cells was consistant with the differential expression of GP3ST. Taken together the results suggested that the expression of GP3ST may be involved in tumor metastasis process by regulation of adhesion ability and expression of integrin αV.