title: Altered ErbB receptor signaling and gene expression in cisplatin-resistant ovarian cancer.
abstract: The majority of ovarian cancer patients are treated with platinum-based chemotherapy, but the emergence of resistance to such chemotherapy severely limits its overall effectiveness. We have shown that development of resistance to this treatment can modify cell signaling responses in a model system wherein cisplatin treatment has altered cell responsiveness to ligands of the erbB receptor family. A cisplatin-resistant ovarian carcinoma cell line PE01CDDP was derived from the parent PE01 line by exposure to increasing concentrations of cisplatin, eventually obtaining a 20-fold level of resistance. Whereas PE01 cells were growth stimulated by the erbB receptor-activating ligands, such as transforming growth factor-alpha (TGFalpha), NRG1alpha, and NRG1beta, the PE01CDDP line was growth inhibited by TGFalpha and NRG1beta but unaffected by NRG1alpha. TGFalpha increased apoptosis in PE01CDDP cells but decreased apoptosis in PE01 cells. Differences in extracellular signal-regulated kinase and phosphatidylinositol 3-kinase signaling were also found, which may be implicated in the altered cell response to ligands. Microarray analysis revealed 51 genes whose mRNA increased by at least 2-fold in PE01CDDP cells relative to PE01 (including FRA1, ETV4, MCM2, AXL, MT3, TRAP1, and FANCG), whereas 36 genes (including IGFBP3, TRAM1, and KRT4 and KRT19) decreased by a similar amount. Differential display reverse transcriptase-PCR identified altered mRNA expression for TCP1, SLP1, proliferating cell nuclear antigen, and ZXDA. Small interfering RNA inhibition of FRA1, TCP1, and MCM2 expression was associated with reduced growth and FRA1 inhibition with enhanced cisplatin sensitivity. Altered expression of these genes by cytotoxic exposure may provide survival advantages to cells including deregulation of signaling pathways, which may be critical in the development of drug resistance.
authors.affiliation: Cancer Research UK Centre, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Macleod
authors.forename: Peter
authors.initials: P
authors.lastname: Mullen
authors.forename: Jane
authors.initials: J
authors.lastname: Sewell
authors.forename: Genevieve
authors.initials: G
authors.lastname: Rabiasz
authors.forename: Sandra
authors.initials: S
authors.lastname: Lawrie
authors.forename: Eric
authors.initials: E
authors.lastname: Miller
authors.forename: John F
authors.initials: JF
authors.lastname: Smyth
authors.forename: Simon P
authors.initials: SP
authors.lastname: Langdon
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D048708:Cell Growth Processes / Q000502:physiology; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D008024:Ligands; D020935:MAP Kinase Signaling System; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018808:Transcription Factor AP-1 / Q000378:metabolism; D016211:Transforming Growth Factor alpha / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D008024:Ligands; D018808:Transcription Factor AP-1; D016211:Transforming Growth Factor alpha; D019869:Phosphatidylinositol 3-Kinases; D020794:Receptor Protein-Tyrosine Kinases; D048049:Extracellular Signal-Regulated MAP Kinases; D002945:Cisplatin