title: An antibody against DR4 (TRAIL-R1) in combination with doxorubicin selectively kills malignant but not normal prostate cells.
abstract: Prostate cancer is a major health problem among American men and new treatment approaches are needed. Tumor necrosis factor related apoptosis-inducing ligand (TRAIL/Apo2L) is a death ligand that can induce apoptosis in some but not all cancer cells. Resistance to TRAIL-mediated apoptosis can be overcome by radiation or chemotherapy. The effect of doxorubicin/TRAIL combination therapy was compared among PC3, normal prostate epithelial (PrEC) and stromal (PrSC) cells and cell viability measured by MTS assay. Combination of doxorubicin and TRAIL caused cytotoxicity in all cells tested, although PrSC were more resistant. There was no correlation between TRAIL phenotype and expression of c-FLIP, caspases or TRAIL decoy receptors, although PrSC failed to express DR4. A DR4-specific antibody, which behaved as an agonist in combination with doxorubicin, selectively induced cell death in malignant but not normal prostate cells. Although normal PrEC expressed DR4 as determined by western blot, flow cytometry revealed that only maligant prostate cancer cells (PC3, JCA-1) and not PrEC's exhibited DR4 surface expression. Therefore, combination of doxorubicin and an antibody to DR4 might have therapeutic potential for the treatment of prostate cancer by selectively targeting malignant prostate cells.
authors.affiliation: Department of Microbiology, 173 Ashley Ave, Medical University of South Carolina, Charleston, South Carolina 29403, USA. johnsocv@musc.edu.
authors.forename: Christina
authors.initials: C
authors.lastname: Voelkel-Johnson
mesh_terms: D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D004317:Doxorubicin / Q000627:therapeutic use*; D019008:Drug Resistance, Neoplasm; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D005434:Flow Cytometry; D006801:Humans; D008024:Ligands; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D011467:Prostate / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000276:immunology*; D017154:Stromal Cells / Q000378:metabolism / Q000473:pathology; D053221:TNF-Related Apoptosis-Inducing Ligand; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; D008024:Ligands; D008562:Membrane Glycoproteins; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D004317:Doxorubicin; D020169:Caspases