title: Bcl-X(L) is a chemoresistance factor in human melanoma cells that can be inhibited by antisense therapy.
abstract: Malignant melanoma is a tumor that responds poorly to a variety of apoptosis-inducing treatment modalities, such as chemotherapy. The expression of genes that regulate apoptotic cell death plays an important role in determining the sensitivity of tumor cells to chemotherapeutic intervention. Bcl-x(L) is an antiapoptotic member of the Bcl-2 family and is universally expressed in human melanoma. To evaluate the Bcl-x(L) protein as a potential therapeutic target in melanoma, the influence of Bcl-x(L) expression levels on the chemoresistance of human melanoma cells was investigated. Overexpression of Bcl-x(L) in stably transfected human melanoma Mel Juso cells significantly reduced sensitivity to cisplatin-induced apoptosis (p < or = 0.05). In a parallel approach, reduction of Bcl-x(L) protein by specific AS oligonucleotide (ISIS 16009) treatment enhanced the chemosensitivity of Mel Juso cells by 62% compared to cells treated with MM control oligonucleotide (ISIS 16967) as well as chemotherapy-induced apoptosis. These data suggest that Bcl-x(L) is an important factor contributing to the chemoresistance of human melanoma. Reduction of Bcl-x(L) expression by AS oligonucleotides provides a rational and promising approach that may help to overcome chemoresistance in this malignancy.
authors.affiliation: Department of Clinical Pharmacology, Section of Experimental Oncology/Molecular Pharmacology, University of Vienna, Vienna, Austria.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Heere-Ress
authors.forename: Christiane
authors.initials: C
authors.lastname: Thallinger
authors.forename: Trevor
authors.initials: T
authors.lastname: Lucas
authors.forename: Hermine
authors.initials: H
authors.lastname: Schlagbauer-Wadl
authors.forename: Volker
authors.initials: V
authors.lastname: Wacheck
authors.forename: Brett P
authors.initials: BP
authors.lastname: Monia
authors.forename: Klaus
authors.initials: K
authors.lastname: Wolff
authors.forename: Hubert
authors.initials: H
authors.lastname: Pehamberger
authors.forename: Burkhard
authors.initials: B
authors.lastname: Jansen
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002470:Cell Survival / Q000187:drug effects; D002945:Cisplatin / Q000627:therapeutic use*; D004351:Drug Resistance; D005434:Flow Cytometry; D006801:Humans; D008545:Melanoma / Q000188:drug therapy* / Q000473:pathology; D016376:Oligonucleotides, Antisense / Q000627:therapeutic use*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000037:antagonists & inhibitors* / Q000235:genetics; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000473:pathology; D014162:Transfection; D014407:Tumor Cells, Cultured; D051020:bcl-X Protein
chemical_list: D000970:Antineoplastic Agents; C494811:BCL2L1 protein, human; D016376:Oligonucleotides, Antisense; D019253:Proto-Oncogene Proteins c-bcl-2; D051020:bcl-X Protein; D011065:Poly(ADP-ribose) Polymerases; D002945:Cisplatin