ABSTRACT
BACKGROUND: Expression of human chorionic gonadotropin beta subunit (hCGß) by epithelial carcinomas is associated with a poor prognosis and has a proposed autocrine growth effect on cancer cells by inhibition of apoptosis. MATERIAL AND METHODS: We transduced the hCGß-expressing bladder cancer cell line SCaBER with short hairpin (sh) RNA lentiviral gene-specific (CGB) constructs and determined its impact on the synthesis of hCGß and the resultant effect on cancer cell growth. RESULTS: Stable CGB gene-silenced clones exhibited a 60%-80% reduction in the level of hCGß expressed and a reduced growth rate of more than 40% compared to wild-type SCaBER cells. CONCLUSIONS: shRNA Lentiviral particles achieve stable knockdown of hCGß translation in the bladder cancer cell line SCaBER. This transforms the phenotype by reducing hCGß expression and cell growth rate. This is consistent with the proposed autocrine/paracrine function of ectopic hCGß expression during oncogenesis.
Subject(s)
Cell Proliferation , Chorionic Gonadotropin, beta Subunit, Human/genetics , RNA, Messenger/genetics , Urinary Bladder Neoplasms/genetics , Base Sequence , Cell Line, Tumor , Humans , RNA, Small Interfering/genetics , Real-Time Polymerase Chain Reaction , Urinary Bladder Neoplasms/pathologyABSTRACT
PURPOSE: Oncolytic herpes simplex virus type 1 (HSV-1) vectors show considerable promise as agents for cancer therapy. We have developed a novel recombinant HSV-1 virus (JS1/34.5-/47-) for purging of occult breast cancer cells from bone marrow of patients. Here, we evaluate the therapeutic efficacy of this oncolytic virus. EXPERIMENTAL DESIGN: Electron microscopy was used to determine whether human breast cancer and bone marrow cells are permissive for JS1/34.5-/47- infection. Subsequently, the biological effects of JS1/34.5-/47- infection on human breast cancer cells and bone marrow were established using cell proliferation and colony formation assays, and the efficiency of cell kill was evaluated. Finally, the efficiency of JS1/34.5-/47- purging of breast cancer cells was examined in cocultures of breast cancer cells with bone marrow as well as bone marrow samples from high-risk breast cancer patients. RESULTS: We show effective killing of human breast cancer cell lines with the JS1/34.5-/47- virus. Furthermore, we show that treatment with JS1/34.5-/47- can significantly inhibit the growth of breast cancer cell lines without affecting cocultured mononuclear hematopoietic cells. Finally, we have found that the virus is effective in destroying disseminated tumors cells in bone marrow taken from breast cancer patients, without affecting the hematopoietic contents in these samples. CONCLUSION: Collectively, our data show that the JS1/34.5-/47- virus can selectively target breast cancer cells while sparing hematopoietic cells, suggesting that JS1/34.5-/47- can be used to purge contaminating breast cancer cells from human bone marrow in the setting of autologous hematopoietic cell transplantation.