[Changes in gene expression profiles of hydatidiform mole and choriocarcinoma as compared with trophoblast...

To study the relationship of changes in gene expression profiles of hydatidiform mole and choriocarcinoma with hyperplasia of trophoblasts.

The differentially expressed genes were analyzed in two pairs of tissues of hydatidiform mole versus normal villi, and in two pairs of normal primary culture trophoblasts versus JAR cell line of chariocarcinoma, using cDNA microarray containing 4096 genes. To confirm the results of cDNA microarray analysis, expressions of some up-regulated genes related to DNA synthesis in normal villi, hydatidiform mole, and 2 choriocarcinoma cell lines (JAR and JEG-3) were examined by immunohistochemistry, immunoblotting and RT-PCR.

A total of 89 genes were differentially expressed in all hydatidiform moles, accounting for 2.2% of the genes arrayed. Of the 89 genes, 24 were up-regulated and 65 were down-regulated. Compared with normal primary trophoblasts, there were 433 genes up-regulated and 380 genes down-regulated in JAR cell line. Forty six genes were up-regulated in both hydatidiform mole and choriocarcinoma, while 13 genes were down-regulated. Some genes associated with cell proliferative inhibition were significantly down-regulated, whereas those associated with cell proliferation, malignant transformation, metastasis and drug resistance were highly up-regulated. The expressions of thymidine kinase 1, the small subunit of ribonucleotide reductase (RRM2) were significantly increased in hydatidiform mole, JAR and JEG-3 cells.

Abnormal expression of genes exists in hydatidiform mole and choriocarcinoma. Hyperplasia of trophoblasts may be related to over-expression of genes coding for synthetic enzymes.