microRNAs as biomarkers of ovarian cancer

ABSTRACT

Introduction: Ovarian carcinoma (OC) is the leading cause of death in women with gynecologic cancers. Most patients are diagnosed at an advanced stage with a low five-year survival rate of 20–30%. Discovering novel biomarkers for early detection and outcome prediction of OC is an urgent medical need. miRNAs, a group of small non-coding RNAs, play critical roles in multiple biologic processes and cancer pathogenesis.

Areas covered: We provide an in-depth look at the functions of miRNAs in OC, particularly focusing on their roles in chemoresistance and metastasis in OC. We also discuss the biological and clinical significance of miRNAs in exosomes and expand on long non-coding RNA which acts as ceRNA of miRNAs.

Expert opinion: miRNAs participate in many biological processes including proliferation, apoptosis, chemoresistance, metastasis, epithelial–mesenchymal transition, and cancer stem cell. They will substantially contribute to our understanding of OC pathogenesis. Given their resistance to the degradation of ribonucleases and availability in plasma exosomes, miRNAs may serve as emerging biomarkers for cancer detection, therapeutic assessment, and prognostic prediction. Being a messenger, exosomal miRNAs are crucial for the crosstalk between cancer cells and stromal cells in tumor microenvironment.

KEYWORDS:

• Ovarian carcinoma
• miRNA
• epithelial–mesenchymal transition
• cancer stem cell
• exosome

Article highlights

• miRNAs play an important role in many aspects of OC pathogenesis including chemoresistance and metastasis, suggesting that they are promising therapeutic targets and survival predictors.

• Exosomes with bioactive miRNAs are crucial for intercellular communication in OC that is critical for pre-metastatic niche.

• OC-derived miRNAs are enriched and highly stable in serum exosomes; thereby, they become promising biomarkers for cancer diagnosis and prognosis prediction.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was funded by a grant from the Natural Science Foundation of China [no. 81872112].