The effect of potential anticancer gene products on breast cancer cell lines

Abstract

Cellular or viral delivery of anti-cancer gene therapeutics typically has been investigated as single agents. More recently combinatorial agents have been investigated for which some combinations have shown synergism. The present study was designed to evaluate three different potential anticancer factors, decorin, interferon beta (IFNb), and tumor necrosis factor (TNF) related apoptotic inducing ligand (TRAIL). The overall hypothesis was that combinatorial treatment of two of anti-cancer factors would be more efficacious and exhibit less toxicity than single treatments in breast cancer cell lines.In order to be able to test this hypothesis, the construction of these anticancer genes was required as well as engineering and expression of transgenes in a cellular production system. Therefore, my thesis project required the isolation of anti-cancer genes from either human genomic or cDNA libraries, verification of sequence fidelity, construction of transgene expression cassettes, and transient transfection of the transgenes in Chinese hamster ovarian (CHO) cells. Secreted cellular protein production was verified in culture media and the anti-cancer effects of conditioned media containing single proteins on growth of human and mouse breast cancer cell lines was measured and compared to commercially available agents. Mesenchymal stem cells (MSCs) have been shown to home to tumors and are under investigation as vehicles for delivering anticancer gene therapeutics. MSC-based anti-cancer gene therapeutics are typically investigated as single agents. The present study was designed to assess the anti-cancer properties of the selected gene products as a prelude to their production from MSCs. This study specifically evaluated decorin, interferon beta (IFNb), and tumor necrosis factor (TNF) related apoptotic inducing ligand (TRAIL) as growth inhibitors in vitro as previous studies have demonstrated their efficacy as growth inhibitors in multiple cancer cell lines including breast cancer in in vitro and in vivo studies. My experimental results indicated that commercially available human and mouse TRAIL inhibited MDA-MB-231, MCF-7, and WM793 human cancer cell lines. TRAIL produced by CHO cells were able to decrease WM793 cancer cell growth, but not illicit a response in MDA-MB-231 or MCF-7 breast cancer cell lines. Further studies are needed to discover the relationship between the combination of these gene products.