Objective: To study the role of human leukocyte antigen-G (HLA-G) in the carcinogenesis and development of choriocarcinoma.
Methods: We designed and synthesized a double strand small interference RNA (siRNA) of HLA-G, then transfected it into a HLA-G overexpressed choriocarcinoma cell line, JEG-3 by lipofectine; HLA-G mRNA level was detected by real time RT-PCR; HLA-G protein level was detected by western blot. The living cells of JEG-3 were counted under microscope after transfection by siRNA.
Results: Double strand siRNA of HLA-G effectively downregulated the mRNA level and the protein level of HLA-G. The mRNA levels by Ct value at different concentration (1.0, 2.5, 5.0 microg/L) were 20.67 +/- 0.02, 21.37 +/- 0.03, 21.43 +/- 0.02, respectively. They were significantly different compared with the control groups which were 20.33 +/- 0.01, 20.37 +/- 0.02, 20.40 +/- 0.03, respectively (P < 0.05). The protein levels were down regulated in different concentration compared with the control groups (0.42 +/- 0.03 vs 1.69 +/- 0.23, 0.37 +/- 0.02 vs 1.62 +/- 0.31, 0.12 +/- 0.04 vs 1.36 +/- 0.22; P < 0.01). Through downregulation of HLA-G expression, the growth of choriocarcinoma cells was inhibited.
Conclusions: Small interference RNA of HLA-G can effectively down regulate HLA-G gene in mRNA and protein levels and inhibit tumor growth in choriocarcinoma. It shows that HLA-G plays an important role in the development of choriocarcinoma.