title: Potential molecular signatures in epithelial ovarian cancer by genome wide expression profiling.
abstract: OBJECTIVE
  Ovarian cancer is the deadliest of all gynecologic cancers because of its late diagnosis and poor treatment outcomes. This study aimed to identify potential molecular signatures associated with biological processes that are implicated in epithelial ovarian cancer (EOC).
  
  
  METHODS
  Expression profiling was carried out on 16 fresh frozen EOC and normal ovarian tissue samples using the Illumina Whole Genome DASL assay (cDNA-mediated annealing, selection, extension and ligation). The differentially expressed genes were analyzed using the GeneSpring GX11.5 and Pathway Studio 8.0 software. The microarray results were validated using the immunohistochemistry analyses.
  
  
  RESULTS
  Unpaired t-test identified 652 (270 up- and 382 downregulated) significant differentially expressed genes (P < 0.001 and fold change ≥2.0). Hierarchical clustering analysis displayed a distinct separation of cancer and normal samples. Gene set enrichment analysis identified alterations in the expression of genes associated with cancer development and progression. Positive immunostaining of claudin-7, ephrin receptor A1 and Forkhead Box M1 in EOC was consistent with the upregulation of these genes in the microarray result. However, the positive immunostaining of fibroblast growth factor-7 in cancer tissues was not in accordance with the downregulation of this gene in the microarray result.
  
  
  CONCLUSIONS
  These results identify significant genes and their related biological processes which may contribute to the better understanding of development and progression of epithelial ovarian cancer.
authors.affiliation: Department of Physiology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
authors.forename: Yin-Ling
authors.initials: YL
authors.lastname: Wong
authors.affiliation: Department of Obstetrics and Gynecology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
authors.forename: Ahmad Zailani Hatta Mohd
authors.initials: AZ
authors.lastname: Dali
authors.affiliation: Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
authors.forename: Isa
authors.initials: I
authors.lastname: Mohamed Rose
authors.affiliation: UKM Medical Molecular Biology Institute, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
authors.forename: Rahman
authors.initials: R
authors.lastname: Jamal
authors.affiliation: Department of Physiology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.|UKM Medical Molecular Biology Institute, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
authors.forename: Norfilza Mohd
authors.initials: NM
authors.lastname: Mokhtar
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D000077216:Carcinoma, Ovarian Epithelial; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009375:Neoplasms, Glandular and Epithelial / Q000235:genetics* / Q000378:metabolism; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor
keywords: biological process; epithelial ovarian cancer; gene expression profiling; immunohistochemistry; microarray