title: Identification of genes that modulate sensitivity of U373MG glioblastoma cells to cis-platinum.
abstract: Scatter factor (hepatocyte growth factor) and its receptor c-Met are increasingly expressed during progression from low-grade to high-grade gliomas. Scatter factor/c-Met signaling induces glioma cell motility, invasion, angiogenesis and resistance to DNA-damaging agents. The latter is relevant to the understanding of the resistance of human gliomas to chemotherapy and radiotherapy. The goal of this study was to identify a set of genes that may contribute to scatter factor-mediated protection of U373MG cells against cis-platinum, a DNA cross-linking agent. We used DNA microarray assays, confirmatory semiquantitative reverse transcription-polymerase chain reaction analysis and functional assays to identify genes involved in the scatter factor-induced resistance of U373MG to cis-platinum. We identified a group of genes that are overexpressed in cells treated with scatter factor plus cis-platinum relative to cells treated with cis-platinum alone and confirmed some of these gene expression alterations by reverse transcription-polymerase chain reaction. Inhibiting the expression of three of these genes--polycystic kidney disease 1, amplified in breast cancer 1 and DEAD/H box helicase 21--using small interfering RNAs reduced survival of cis-platinum-treated cells and partially reversed the scatter factor protection against cis-platinum. Dominant-negative Akt and IkappaB super-repressor expression vectors inhibited the scatter factor protection, and abrogated the ability of scatter factor to alter the expression of DEAD/H box helicase 21 and polycystin (PKD1) within the context of cis-platinum exposure. The Akt and nuclear factor-kappaB inhibitors had no effect on amplified in breast cancer 1 expression. These studies implicate DEAD/H box helicase 21, polycystin (PKD1) and amplified in breast cancer 1 as novel transcription-dependent regulators of scatter factor-mediated glioma cell protection against cytotoxic death, and identify other potential regulators for future study.
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center/Georgetown University, Washington, District of Columbia 20057-1469, USA.
authors.forename: Yongxian
authors.initials: Y
authors.lastname: Ma
authors.forename: Ren-qi
authors.initials: RQ
authors.lastname: Yuan
authors.forename: Saijun
authors.initials: S
authors.lastname: Fan
authors.forename: Changyan
authors.initials: C
authors.lastname: Hu
authors.forename: Itzhak D
authors.initials: ID
authors.lastname: Goldberg
authors.forename: John J
authors.initials: JJ
authors.lastname: Laterra
authors.forename: Eliot M
authors.initials: EM
authors.lastname: Rosen
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D015153:Blotting, Western; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000235:genetics*; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000627:therapeutic use*; D016172:DNA Fingerprinting; D015536:Down-Regulation / Q000187:drug effects; D019008:Drug Resistance, Neoplasm; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D005822:Genetic Vectors; D005909:Glioblastoma / Q000188:drug therapy* / Q000235:genetics*; D017228:Hepatocyte Growth Factor / Q000502:physiology*; D006801:Humans; D016328:NF-kappa B / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D051058:Oncogene Protein v-akt / Q000235:genetics; D019859:Proto-Oncogene Proteins c-met / Q000502:physiology*; D012334:RNA, Neoplasm / Q000302:isolation & purification; D034741:RNA, Small Interfering; D014162:Transfection
chemical_list: D000970:Antineoplastic Agents; D016328:NF-kappa B; D012334:RNA, Neoplasm; D034741:RNA, Small Interfering; D017228:Hepatocyte Growth Factor; D019859:Proto-Oncogene Proteins c-met; D051058:Oncogene Protein v-akt; D002945:Cisplatin