Introduction: Ovarian cancer is one of the most common malignancies in women and the fifth cause of cancer-related deaths in women worldwide. Contrary to the challenges in developing new clinical markers using the conventional methods, recent advances in genomics and proteomics have led to identification of candidate and promising biomarkers for the diagnosis of ovarian cancer. Human epididymis protein 4 (HE4) is such a marker that has recently been reported to correlate with recurrence or progression of epithelial ovarian cancer. The purpose of this study was to measure the expression level of HE4 gene in women with ovarian cancer. Methodology: We evaluated and compared paraffin-embedded tissue samples of 20 ovarian cancer patients with 10 samples from healthy individuals. RNA was initially extracted from the samples and cDNA was synthetized. Gene expression level was then measured using real-time polymerase chain reaction (PCR). Results: Our results demonstrated that HE4 gene expression level was significantly higher in samples of patients with ovarian cancer compared with samples from healthy individuals. Moreover, higher levels of HE4 gene expression were associated with more advanced disease and larger tumor size. Conclusion: HE4 gene over-expression has the potential to be used as a biomarker for detecting early-stage ovarian cancer in women. Future more comprehensive studies are needed to confirm our findings.
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