Transfection of Antisense Chorionic Gonadotropin β Gene into Choriocarcinoma Cells Suppresses the Cell Proliferation and Induces Apoptosis

• Published in: The journal of clinical endocrinology and metabolism 2005-08, Vol.90 (8), p.4873-4879
• Main Authors: Hamada, Anna Lissa, Nakabayashi, Koji, Sato, Asomi, Kiyoshi, Kenji, Takamatsu, Yukou, Laoag-Fernandez, Jovelle B., Ohara, Noriyuki, Maruo, Takeshi
• Format: Article
• Language: English
• Subjects: Apoptosis; Biological and medical sciences; Cell Division; Cell Line, Tumor; Choriocarcinoma - therapy; Chorionic Gonadotropin, beta Subunit, Human - genetics; DNA, Antisense; Endocrinopathies; Female; Genetic Therapy - methods; Humans; In Situ Nick-End Labeling; Medical sciences; Transfection; Uterine Neoplasms - therapy
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.2004-2458

Context: Choriocarcinoma cells not only synthesize human chorionic gonadotropin (hCG), but also express LH/CG receptors on the cell membrane. This suggests that the hCG and LH/CG receptors may play a role in regulating the biological function of choriocarcinoma cells in an autocrine/paracrine manner. Objective and Methods: The objective of this study was to ascertain whether the inhibition of CGβ gene expression in choriocarcinoma cells affects their proliferation and apoptosis. Expression vector bearing antisense CGβ gene was transfected into the choriocarcinoma cell line, JAr. CGβ protein synthesis was monitored by Western immunoblot, and CGβ mRNA expression was determined by RT-PCR. Cell proliferation was assessed by 3-[4,5-dimethlthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay and nuclear incorporation of 5-bromo-2′-deoxyuridine, and the apoptosis-positive rate was assessed by terminal deoxynucleotidyltransferase-mediated deoxy-UTP nick end labeling analysis and nuclear staining with Hoechst 32258. Results: JAr cells transfected with antisense CGβ gene (JAr-aCGβ cells) showed a significant decrease in hCG production and cell proliferation compared with untransfected and mock-transfected cells. The apoptosis-positive rate of the JAr-aCGβ cells significantly increased compared with that of the controls. LH/CG receptor expression in JAr-aCGβ cells decreased compared with that in controls. By contrast, supplementation of exogenous hCG significantly increased the LH/CG receptor expression and viability of JAr-aCGβ cells. Conclusions: These results suggest that hCG, through its binding to the LH/CG receptor, may augment proliferation and inhibit apoptosis in choriocarcinoma JAr cells, and that the introduction of an antisense gene may be a potential approach to the inhibition of choriocarcinoma cell growth.