PT - JOURNAL ARTICLE AU - BEATA B. BURCZYNSKA AU - LATIFA KOBROULY AU - STEPHEN A. BUTLER AU - MAHMOUD NAASE AU - RAY K. ILES TI - Novel Insights into the Expression of <em>CGB1</em> &amp; <em>2</em> Genes by Epithelial Cancer Cell Lines Secreting Ectopic Free hCGβ DP - 2014 May 01 TA - Anticancer Research PG - 2239--2248 VI - 34 IP - 5 4099 - http://ar.iiarjournals.org/content/34/5/2239.short 4100 - http://ar.iiarjournals.org/content/34/5/2239.full SO - Anticancer Res2014 May 01; 34 AB - Background: Ectopic secretion of human chorionic gonadotrophin free beta (hCGβ) by epithelial cancer is associated with aggressive tumors which more readily metastasize, possibly by acting as an autocrine anti-apoptotic agent. hCGβ is encoded by six homologous CGB genes, with poorly-understood variable transcriptionally active expression profiles; CGB1 and CGB2 have always been considered pseudogenes. However, transcripts from CGB1 and -2 can be detected in placental, testicular and pituitary tissues. The expression and function of these genes in cancer is less well-known. Materials and Methods: Expression profiles of CGB genes in epithelial cancer cells by quantitative polymerase chain reaction (qPCR) were explored, along with the consequence of specific siRNA silencing of CGB1 and 2. Immunohistochemical and immunoassay techniques were used to detect the translation and secretion of hCGβ in these cells. Results: CGB1 and -2 gene transcripts were only detected in cells which secreted hCGβ. siRNA-mediated silencing of CGB1 and -2 transcripts significantly reduced secreted protein in concordance with a reduction in cell survival to a greater degree than that of other CGB genes. Conclusion: CGB genes 1 and 2, previously considered as pseudogenes, are notably expressed by epithelial cancer cell lines. The transcription of these genes, but not other CGB genes, correlates with a functionally expressed protein and propensity for cancer growth.