['In this report, we studied the role of Hpa in metastatic capability of human choriocarcinoma. At the same time, we investigated the effect of Hpa antisense oligodeoxynucleotide (ASODN) on inhibition of invasiveness of human choriocarcinoma.', 'The different invasion ability between JEG-3 and JAR cell lines was proved by Matrigel invasion assay in vitro. Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analyses were carried out respectively to determine Hpa gene and protein expression; the localization of this molecule was demonstrated by immunohistochemistry. Finally, Hpa antisense oligodeoxynucleotide (ASODN) was transfected into JEG-3 cells and Hpa mRNA and protein were quantified by RT-PCR and Western blot. The effect of ASODN on the metastatic capability of JEG-3 was evaluated by Matrigel invasion assay.', '(1) We proved that the invasion ability of JEG-3 cell line was stronger than that of JAR cell line (P<0.05). (2) We found that the Hpa gene and protein in JEG-3 and JAR cell lines were significantly higher than those in normal chorion (P<0.05). On the other hand, we detected that JEG-3 expressed much more Hpa than JAR (P<0.05). (3) Both in JEG-3 cell and in JAR cell, we found that Hpa protein express in cytoplasm. (4) After transfection of Hpa ASODN, Hpa mRNA and protein expression in JEG-3 cell decreased 4- and 5-fold. At the same time, we also observed that the invasion ability of JEG-3 cell was weakened than before (P<0.05).'] Does heparanase expression correlate with metastatic capability in human choriocarcinoma?