<em>ZNF385B</em> and <em>VEGFA</em> Are Strongly Differentially Expressed in Serous Ovarian Carcinomas and Correlate with Survival

<div><h3>Background</h3><p>The oncogenesis of ovarian cancer is poorly understood. The aim of this study was to identify mRNAs differentially expressed between moderately and poorly differentiated (MD/PD) serous ovarian carcinomas (SC), serous ovarian borderline tumours (SBOT) and superficial scrapings from normal ovaries (SNO), and to correlate these mRNAs with clinical parameters including survival.</p> <h3>Methods</h3><p>Differences in mRNA expression between MD/PD SC, SBOT and SNO were analyzed by global gene expression profiling (n = 23), validated by RT-qPCR (n = 41) and correlated with clinical parameters.</p> <h3>Results</h3><p>Thirty mRNAs differentially expressed between MD/PD SC, SBOT and SNO were selected from the global gene expression analyses, and 21 were verified (p<0.01) by RT-qPCR. Of these, 13 mRNAs were differentially expressed in MD/PD SC compared with SNO (p<0.01) and were correlated with clinical parameters. ZNF385B was downregulated (FC = −130.5, p = 1.2×10⁻⁷) and correlated with overall survival (p = 0.03). VEGFA was upregulated (FC = 6.1, p = 6.0×10⁻⁶) and correlated with progression-free survival (p = 0.037). Increased levels of TPX2 and FOXM1 mRNAs (FC = 28.5, p = 2.7×10⁻¹⁰ and FC = 46.2, p = 5.6×10⁻⁴, respectively) correlated with normalization of CA125 (p = 0.03 and p = 0.044, respectively). Furthermore, we present a molecular pathway for MD/PD SC, including VEGFA, FOXM1, TPX2, BIRC5 and TOP2A, all significantly upregulated and directly interacting with TP53.</p> <h3>Conclusions</h3><p>We have identified 21 mRNAs differentially expressed (p<0.01) between MD/PD SC, SBOT and SNO. Thirteen were differentially expressed in MD/PD SC, including ZNF385B and VEGFA correlating with survival, and FOXM1 and TPX2 with normalization of CA125. We also present a molecular pathway for MD/PD SC.</p> </div

Cluster analysis heatmap.

<p>Cluster analysis heatmap of the expression levels (ΔCq values) of 21 differentially expressed mRNAs (p<0.01) in moderately (MD) and poorly differentiated (PD) serous ovarian carcinomas (SC), serous ovarian borderline tumours (SBOT) and superficial scrapings from normal ovaries (SNO). Each column represents an mRNA and each row a sample. The more over-and under-expressed the mRNA, the brighter the red and blue colour, respectively. Due to technical analysis errors for DYNLRB2, CRABP2, CRISP2, CRISP3 and LCN2 in sample nr 7, 21 and 26, these values are calculated as the mean ΔCq values of each subgroup. Further abbreviations are given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0046317#pone-0046317-t003" target="_blank">Table 3</a>.</p

Molecular pathway for moderately and poorly differentiated serous ovarian carcinomas.

<p>▾acts on (– direct interaction, -- indirect interaction), _⊥ inhibits. The pathway was facilitated through Ingenuity Pathway Analysis. Abbreviations are given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0046317#pone-0046317-t003" target="_blank">Table 3</a>.</p

Clinicopathological and laboratory information for patients selected for RT-qPCR analyses.

a<p>12 MD, 9 PD. SD: Standard deviation. CI: Confidence Interval. Further abbreviations are given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0046317#pone-0046317-t001" target="_blank">Table 1</a>.</p

Kaplan-Meier survival curves.

<p>Overall survival curves according to ZNF385B mRNA expression level (FC) tertiles (<b>A</b>) and progression-free survival curves according to VEGFA mRNA expression level (FC) tertiles (<b>B</b>) in patients with moderately and poorly differentiated serous ovarian carcinomas. A: High expression. B: Intermediate expression. C: Low expression.</p