Differential expression of Rho guanine nucleotide exchange factor 25 in human epithelial ovarian cancer.

Epithelial ovarian cancer (EOC) is the most lethal gynecologic cancer (1). We performed discovery of genes associated with epithelial ovarian cancer and of the high-grade serous ovarian cancer (HGSC) subtype, using published microarray data (2, 3) to compare global gene expression profiles of normal ovary or fallopian tube with that of primary tumors from women diagnosed with epithelial ovarian cancer or HGSC. We identified the gene encoding Rho guanine nucleotide exchange factor 25, ARHGEF25, as among the genes whose expression was most different in epithelial ovarian cancer as compared to the normal fallopian tube. ARHGEF25 expression was significantly lower in high-grade serous ovarian tumors relative to normal fallopian tube. ARHGEF25 expression correlated with progression-free survival in patients with ovarian cancer. These data indicate that expression of ARHGEF25 is perturbed in epithelial ovarian cancers broadly and in ovarian cancers of the HGSC subtype. ARHGEF25 may be relevant to pathways underlying ovarian cancer initiation (transformation) or progression.